DE4333145A1 - Active vibration damping system for motor vehicle - uses vibration generator for active damping of detected vibration within passenger space due to vehicle engine - Google Patents

Abstract

The vibration damping system uses a reference signal generator providing a reference signal dependent on the vibration frequency of the motor vehicle engine (4) combined with a vibration signal dependent on the detected vibration at a given location within the vehicle passenger space to provide a vibration damping control signal supplied to a vibration generator (11). Pref. the vibration within the vehicle passenger space is detected via a microphone (10), the vibration generator being provided by at least one loudspeaker. USE/ADVANTAGE - For reducing vibration noise within vehicle passenger space. Adapts well to changes in surroundings.

Description

The invention relates to a vibration damping system for a Vehicle that forms a system for controlling Vibra ions or vibrations in a vehicle body are generated, and particularly relates to an improvement a vibration damping system in which the vehicle vibration is damped by oscillation (after standing with vibrating) of a certain vibra tion element on the vehicle in a phase that to that the vehicle vibration is opposite, and with a Amplitude equal to that of vehicle vibration, and by an actuator. In this description exercise, the term "vehicle vibration" should not only be used Vibration of the vehicle body, but also the vibration of air, d. H. Include noises.

As an active type vibration damping system for one Vehicle has become known a system that one Reference signal generator, which has a reference signal corresponding to a vibration generated by the engine of the vehicle, an adaptive filter, which generates a control signal (vibration signal) which the opposite phase has like the reference signal and back is obviously equal to the amplitude, a vibration generator supply device such as a loudspeaker, which the control signal receives and the vehicle body vibrates, and a Vi bration detection device like a microphone, which the Vibration of the vehicle body and / or air inside of the vehicle body is sensed and an LMS Algorithm operation device (LMS = method of smallest middle squares), which sequentially the fil terfactor of the adaptive filter updated so that the of the vibration detection device detected vibration ge  is dampened. See e.g. B. the unaudited Japanese Pa Publication No. 1 (1989) -501344.

That is, in the reference signal generator from the Refe renzsignal an ignition pulse signal corresponding to the vibration of the motor and a reference signal in the form of a digital signals generated. The reference signal is used in the adaptive Filter entered and the adaptive filter sets the ver strengthening, phase and the like of the reference signal and generates a control signal which generates the vibration device causes a vibration to be generated which Vibration of the engine extinguishes in the position where the Vi bration detection device is arranged. The reference signal is also the LMS algorithm operation facility entered and the filter factor of the adaptive filter is optimized by constantly updating it so that the level of the signal output from the vibration detection device is lowered or reduced.

Thus, the conventional vibration damping system the signal output from the vibration detection device used to adjust the filter factor of the adaptive filter optimize and control signals to attenuate the through the Vibration source (engine) generated vibration are basic additionally generated only from the reference signals that are generated are based on the information about the cycle or the frequency of the vibration source and sequentially the adaptive filter can be entered. From this point of view in the conventional vibration damping system so-called intrusion control or forward control or a pure control in contrast to the regulation.

With such a conventional vibration damping system a large amount of calculation has to be done in a short time be the filter factor of the adaptive filter in each Moment or always to update. Especially if everyone Components of the vibra generated by the vibration source  are to be dampened, the calculation quantity is to be updated sieren the filter factor for the computing power of the normal Processor or the like too high, which is generally in the Vibration damping system is used for a vehicle to be processed or calculated in a short time the. Accordingly, conventional vibration damping systems are aimed generally depends on a certain vibration component dampen a cyclical or periodic vibration, the is generated by the vibration source.

Generally only a certain vibration component is one cyclic vibration generated by the vibration source becomes the object of a control in the conventional vibra tion damping system as described above. However, since it It has become known that the cyclical vibration that occurs on is generated due to the vibration of the engine in the driving vibration prevailed and a certain vibration component (e.g. the secondary or second component with a frequency twice as high as the engine speed) has a higher level than the others Components, vehicle vibration can be satisfactory be dampened by such a certain vibration component as the control object. Are further the conventional vibration damping systems, in which the Forward control is effected, advantageously in that with regard to their ability to perform ("follow up performance ") on changes in the periodicity of the Object vibration and in terms of their response behavior superior to control.

A satisfactory vibration damping effect can but not always with the traditional vibration damper system. The one generated in the vehicle Vibration is often strongly affected by the environment of the System influences how operating states of the vehicle, Characteristics of the fault, state of the parameters that the Form system, and the like. What z. B. the condition or  the condition of vibration of air in the passenger compartment (Noise) which is caused by the vibration of the motor is caused by the noise level in a certain frequency band in which a certain Vibration component of engine vibration exists when there is the vehicle is in a certain operating state, the Noise level sometimes essentially over the entire period quenzband or the entire frequency range e.g. B. due to a change in the properties of the Malfunction when the operating state of the vehicle changes.

In the case of noise attenuation, as long as the Noise level in a certain frequency band, in which a certain vibration component of the engine vibration exis tiert, is higher than the noise level in the other Fre quenzband, a satisfactory damping effect the conventional vibration damping system can be obtained, by considering the particular vibration component as the object of the controller. However, if the noise level in the we considerably uniform over the entire frequency range is high, can have a satisfactory damping effect through the conventional vibration damping system, not he aims to be.

These problems with conventional vibration damping systems are caused by the fact that only one be determined the vibration component as the object of the control can be tightened because on the other hand or in the other case the calculation amount or the calculation effort for the Aktua lizing the filter factor of the adaptive filter in too large increases. Accordingly, there is a desire for one Vibration damping system, which the entire vibration as can use the control object.

The present applicant has a vibration damping system proposed in which a controller with feedback  or a regulation is effected, the control signal directly based on a detection signal from the Vibration detection device is generated, which Rege differs from the feedforward control described in the conventional vibration damping system, being the control signal based on every moment generated reference signal is generated. See the Japanese Patent Application No. 4 (1992) -32217 and the like.

This vibration damping system includes a vibrator generating device like a speaker that the cycle or the period of engine vibration and vibration dampens the energy of the engine vibration, a vibration detection solution device like a microphone, which the vibration of the Vehicle body or air detected in the passenger compartment or sensed, and an adjustment device that the Vibra setting energy, which is from the vibration generation direction is generated, and the output of the adjuster device to the vibration generating device after it is corrected based on the detection signal from the vibration detection device and the transmission properties between the vibration detection device device and the vibration generating device, whereby direct the output signal (control signal) to the Vibra at any moment tion generating device is optimized and the vibration is steamed. According to this type of taxation, the will be made the computational effort does not increase so much, even if the total vibration generated in the vehicle body than that Object of the control is used because the control signal directly based on the detection signal from the Vi bration detection device is generated.

A design or layout technique of an optimal return coupling system through the optimal control theory can on that Vibration damping system can be applied. The LQG rules or control theory (LQG = linear quadratic Gaussver drive), which is conventionally common as the opti  male control theory, but ensures optimization not in an idealized state and accordingly is not been practical, a vibration damping system one optimal feedback control system through the LQG theory to interpret. Recently, the H∞ control theory has as a new rule theory attracted attention that can replace the LQG theory (Hidenori Kimura: From LQG to H∞-Measurement and control, Vol. 29, No. 2, pp. 111/119, Fe bruar 1990, and the like). One by the H∞ rule theory designed optimal feedback control system or Regelsy stem is of robust stability and practical and demge The calculation quantity to be carried out or the not too much, even if the total vibration generated in the vehicle body as the object of control in a vibration damping system is accepted in which an optimal control or Feedback system is used by the H∞ control theory like a vibration damping system with a control of the forward type as the referring applicant previously submitted has hit.

However, although with such a vibration damping system Feedback control an effective vibration damping effect can create when the object vibration in a uniformi is steady, it can be satisfied providing vibration damping effect in one state not deliver in which the object vibration transition in response to changes in the operating state of the Vehicle or the like changes, because of their poor subsequent performance and poor response behavior on the controller.

As can be seen from the above description, there are conventional vibration damping systems for vehicles Lich their adaptivity to changes in the environment of the Systems defective and can give a satisfactory vibra tion damping effect does not deliver when the environment  of the system changes and the state of the vibration changes, although it has a satisfactory vibration damping kung can deliver if the vibration is in a be in good condition.

In view of the above observations and descriptions exercise is the main object of the present invention Vibration damping system for a vehicle to specify which ches is excellent in terms of its adaptability to Ver changes in the environment of the system.

According to the invention, the two systems described above, d. H. a feedforward type control system which a Control signal generated based on the reference signal, and a feedback type control system which is a control signal based on a signal from a vibration sensor like a microphone, which is a vibration generator supply device such as a speaker causes a to generate such vibration that by the vibra tion sensor vibration is damped, in combination used with each other regarding the fact that their Values are mutually interpolated or that they are one interpolate others.

That is, the vibration damping system for a vehicle according to the present invention forms a system which in the Vehicle generated vibration as an object of control and which uses a reference signal generator has a reference signal based on informa tion generated over the cycle of a vibration source, the creates a cyclic vibration in the vehicle, a Vi bration detection device like a microphone, which a Vibration in a predetermined position in the vehicle detected and outputs a vibration signal, a vibration generating device such as a speaker that a Vi bration generates a first surgical device that the Reference signal and the vibration signal from the reference si  gnalgenerator or the vibration detection device emp catches a first control signal generated by processing the Reference signal, so that by the vibration detection device detected vibration is damped, and the first Outputs control signal to the vibration generating device, and a second operating device which controls the vibration signal received from the vibration detection device generates a second control signal which is designed to vibration detected by the vibration detector dampen, and the second control signal to the vibration generation device gives up.

According to one embodiment of the present invention, he an environmental condition detector detects the condition a predetermined factor of the environment of the system and a selector selectively causes one of the first and second operation means, according to the state the predetermined factor of the system environment ten or to operate, which is from the ambient state detection solution device is detected.

That by the vibration damping system of the present Invention "system" means a control system in which has a variety of elements like an object of tax generation (the vibration generated in the vehicle) a vibra tion damping mechanism, a vibration source, a vibra tion transmission path and the like systematically combi be kidneyed.

The "environment of the system" means state within or outside of the system which has some influence on the system have like a target value, disturbances, parameters that form the system. E.g. are a predetermined one in the driving generated vibration, the operating state of the vehicle, the state of the calculation of the operating device, the State of the operating device, the state of the road  surface, the weather condition and the like in the area Exercise of the system included.

The term "predetermined vibration" means the vibra tion, which is the object of the control of the system or another vibration that affects the object of the controller or is related to this.

According to another embodiment of the present invention The second operating device generates the second Control signal by setting a vibration energy for the vibration generating device based on the Vibration detection device and correction of the vibra tion energy based on the vibration signal and Transmission properties between the vibration detection device and the vibration generating device.

The first operation device receives the output signals from the reference signal generator and the vibration detector solution device and the first control signal is generated by processing the reference signal such that the of the vibration detection device detected vibration ge is dampened. The first control signal is the vibrator generating device entered that corresponds to a vibration generated after the first control signal. The one from the vibra tion generating device generated vibration and by the vibration of the vibration source caused vibration cancel each other out, causing a certain com component of the detected by the vibration detection device Vibration is damped. The second surgical facility receives the output signal from the vibration detection direction and generates the second control signal on the ground position of the output signal from the vibration detection direction. The second control signal is the vibration generator supply device entered, corresponding to a vibration generated the second control signal. That through the vibrations generating device generated vibration and that by the  Vibration of the vibration source caused vibration extinguish each other, causing the vibra tion detection device is detected vibration is damped.

The first surgical device is in terms of behavior on changes in vibration that lead to Tax is superior, although it is a limited number or set of vibration components as the object of the Control can use. If the number of vibrating comm components used as the object of control be increased in the first operating device the calculation effort increases too much. The second In contrast, surgical equipment can do a lot number of vibration components as the object of control use without a large increase in the calculation amount, even though their response to Ver Changes in the vibration to be controlled or regulated is not superior.

Thus, by using the first and second Opera tion device in combination the vibration damping system such an excellent adaptability to changes in the environment of the system show that with the conventional Vibration damping systems could not be obtained.

E.g. becomes the first surgical facility normally causes to work, and the second operation device is prompted instead of the first surgical facility operate when it is detected that that detected in the vehicle Vibration essentially over the entire frequency range increases. If the vibration generated in the vehicle in the increases substantially over the entire frequency range it is difficult to use the first surgical device to obtain satisfactory vibration damping effect. In such a case, better vibration damping effect is obtained by damping the entire vibration with the second operating device.  

If the vibration generated in the vehicle is in one steady or steady state is get a better vibration damping effect by damping total vibration from the second operation direction, because by damping a certain component of the Vibration from the first operating device. Farther, when the vibration is in a steady state can find even the second surgical device, the in terms of their response to changes in vibration is not superior, a satisfactory one Show vibration damping effect. Accordingly, if the in the Vehicle generated vibration in a steady State, the second operation is caused facility works.

When the vehicle accelerates or brakes, changes the vibration generated in the vehicle temporarily and accordingly, a quick response is a quick on speaking behavior on changes in vibration required or requested. If the vehicle accelerates or brakes, the first operating device is caused tion works, and if the vehicle with constant Ge speed driving, can better vibration damping effect is obtained by damping the entire vibration and the second operation device is caused to is working.

Since the object of control of the first operating device is a certain component with a high level the first operating device sometimes a first control signal from which from the vibration generating device requests to output a vibration that is its initial limit exceeds. In such a case, a better Vi anti-friction effect are obtained by causing that the second operating device works.

Fig. 1 is a schematic view of a first embodiment of the present invention is a vibration damping system in accordance with a vehicle provided;

Fig. 2 is a block diagram showing the structure of the control device used in the first embodiment;

Fig. 3 is a block diagram showing the structure of the control operation section used in the control device shown in Fig. 2;

Fig. 4 is a block diagram showing the structure of the first operation section shown in Fig. 3;

Fig. 5 is a block diagram showing the structure of the second operation section shown in Fig. 3;

Fig. 6 is a flowchart for explaining the operation of switching the first operation section and the second operation portion shown in Fig. 3,

Fig. 7 is a timing chart for explaining the Umschal is tens of operation sections according to the engine speed;

Fig. 8 is a schematic view of the present invention is a vehicle provided with a vibration damping system according to a second embodiment;

Fig. 9 is a block diagram showing the structure of the control device used in the second embodiment;

Fig. 10 is a block diagram showing the structure of the control operation section used in the control device shown in Fig. 9;

Fig. 11 is a flowchart for explaining the operation of switching the first operation section and the second operation section shown in Fig. 9;

Fig. 12 is a timing chart for explaining the order of the switching operation sections according to a change in the vibration of the passenger cell bottom;

Fig. 13 is a flow chart for explaining the operation of switching the first operation section and the second operation portion in the vibration damping system according to a third embodiment of the present invention;

Fig. 14 is a timing chart for explaining the order to shift the operating or operating sections in accordance with the amplitude of the vibration of the passenger cell bottom;

Fig. 15 is a block diagram showing the structure of the control device which, in the vibration damping system according to a fourth embodiment of the present invention is applied;

Fig. 16 is a block diagram showing the structure of the control operation section used in the control device shown in Fig. 15;

Fig. 17 is a block diagram showing the structure of the control device which is in a vibration damping system according to a fifth embodiment of the present invention is applied;

Fig. 18 is a block diagram showing the structure of the control operation section used in the control device shown in Fig. 17;

Fig. 19 is a flowchart for explaining the operation of switching the first operation section and the second operation section shown in Fig. 18;

Fig. 20 is a timing chart for explaining switching of the operation sections according to the change in the vibration signal from the microphone;

Fig. 21 is a block diagram showing the structure of the control operation section used in a vibration damping system according to a sixth embodiment of the present invention;

Fig. 22 is a block diagram showing the structure of the control operation section, which is in a vibration damping system according to a seventh embodiment of the present invention is applied;

Fig. 23 is a flowchart for explaining the operation of switching the first operation section and the second operation section shown in Fig. 22;

Fig. 24 is a timing chart for explaining the switching of the operation sections in order according to the change in the control signal output from the operation section;

FIG. 25 is a block diagram showing the structure of the control operation section used in a vibration damping system according to an eighth embodiment of the present invention;

Fig. 26 is a block diagram showing the structure of the control operation section used in a vibration damping system according to a ninth embodiment of the present invention;

Fig. 27 is a block diagram showing the structure of the control device which is in a vibration damping system according to a tenth embodiment of the present invention;

Fig. 28 is a block diagram showing the structure of the control operation section used in Fig. 27; and

Fig. 29 is a block diagram showing a modification of the second operation section which can be used in the above embodiments.

Fig. 1 is a provided with a vibration damping system according to a first embodiment of the present invention the vehicle. In Fig. 1, a vehicle body 1 has an engine compartment 2 and a passenger compartment 3 , which are provided at the front of the section and the middle section thereof. An engine 4 is in the engine compartment 2 angeord net and elastically mounted on the vehicle body 1 by means of stanchions (not shown) which elastically support the lower portion of the engine 4 . Reference numerals 5 , 6 and 7 each represent a steering wheel, front and rear seats.

An engine control unit 9 is arranged in a dashboard 8 at the front end of the passenger compartment 3 . A plurality of microphones 10 and a plurality of loudspeakers 11 are arranged in predetermined positions in the passenger compartment 3 . The microphones 10 serve to detect a vibration in predetermined positions in the passenger compartment 3 and are arranged in positions which are important for the feeling and the way of hearing of the passengers, such as on a section of a headrest of the front seat 6 on one side of the Rear seat 7 and the like. The loudspeakers 11 vibrate air or vibrate air in the passenger compartment 3 . For the sake of simplicity, the case where a single microphone 10 and a single speaker 11 are provided will be described below.

The output signal of the microphone 10 is input to a control device 16 which controls the speaker 11 to attenuate the vehicle vibration based on a reference signal r (to be described later) and a vibration signal m which is detected by the microphone 10 .

The structure of the control device 16 is shown in FIG. 2. An engine revolution cycle measuring circuit 17 can be seen, which measures the cycle or the period of the engine revolution on the basis of the ignition signals of the engine 4 and outputs a cycle signal t, a reference signal generator 18 which outputs a reference signal r which indicates the vibration of the engine 4 relates, based on the cycle of the engine revolution, which is detected by the engine revolution cycle measuring circuit 17 . Furthermore, an amplifier 19 can be seen, which amplifies the vibration signal from the microphone 10 with a preset gain, a low-pass filter 20 , which filters the low-frequency components of the vibration signal, which is amplified by the amplifier 19 , and an AD converter 21 , which converts the analog vibration signal, which is filtered by the low-pass filter 20 , into a digital vibration signal m. Also shown are a control operation section 22 which receives the cycle signal t from the engine revolution cycle measuring circuit 17 , the reference signal r from the reference signal generator 18 and the vibration signal m from the AD converter 21 and generates a control signal s (speaker signal) which generates the According to speaker 11 controls or drives to dampen the vibration detected by the microphone 10 .

A DA converter 23 converts the digital control signal s generated by the control operation section 22 into an analog signal, and a low-pass filter 24 filters the low-frequency components of the control signal s from the D / A converter 23 . An amplifier 25 amplifies the control signal S, which is filtered by the low-pass filter 24 , with a predetermined gain. The control signal s, which is amplified by the amplifier 25 , is output to the loudspeaker 11 .

An accelerator stroke measuring circuit 26 measures the degree of depression of the accelerator pedal and a vehicle speed measuring circuit 27 measures the vehicle speed b based on predetermined signals from the engine control unit 9 . The outputs of these measuring circuits 26 and 27 are input to the control operation section 22 .

Fig. 3 shows the structure of the control operation section 22. A first operation section 28 and a second operation section 29 can be seen . The reference signal r from the reference signal generator 18 and the vibration signal m from the microphone 10 are input to the first operation section 28 . The first operation section 28 generates a first control signal s1 by processing the reference signal r such that the vibration detected by the microphone is damped, and outputs the first control signal s1 to the speaker 11 . In the first operation section 28 , an adaptive LMS algorithm is used as the algorithm for generating the first control signal s1.

That is, as shown in FIG. 4, the first operation section 28 has a digital filter 31 which is modulated or realizes the transfer function H from the time at which the control operation section 22 drives the first control signal s1 of the speaker 11 outputs until the time when the change in the vehicle vibration due to the driving or driving of the speaker 11 is detected by the microphone 10 and the detection signal of the microphone 10, the control operation section 22 is input. A convergence factor multiplier circuit 32 multiplies the signal m1 from the microphone 10 by a predetermined convergence factor α. A multiplier 33 multiplies the output of the digital filter 31 (transfer function H) by the output of the convergence factor multiplier circuit 32 . An adaptive filter 34 updates the filter factor based on the output of the multiplier 33 each time the multiplier 33 outputs something, and processes the reference signal r based on the updated filter factor to output to the speaker 11 a first control signal s1 which has a phase opposite to the motor vibration and an amplitude equal to that of the motor vibration.

The second operation section 29 receives a vibration signal m2 from the microphone 10 and the cycle signal t from the engine revolution cycle measuring circuit 17 , adjusts the vibration energy of the speaker 11 , corrects it based on the signal m1 from the microphone 10 and the transmission characteristics between the Microphone 10 and the speaker 11 and then outputs the corrected signal to the speaker 11 as a second control signal s2.

Specifically, the second operation section 29 , as shown in Fig. 5, includes a circuit 36 which sets the vector period of the output signal to the speaker 11 based on the cycle signal t from the motor revolution cycle measuring circuit 17 , a circuit 37 , which converts the matrix of the impulse response, which represents the transmission properties between the microphone 10 and the loudspeaker 11 , into a time series, a circuit 38 which optimizes the vector with the time series of the impulse response and the vibration signal m2 at all times , which is output by the microphone 10 , and a circuit 39 which converts the vector signal from the circuit 38 into a time series, whereby the second control signal s2 (loudspeaker signal) is generated.

In Fig. 3, an acceleration-deceleration-drive determination circuit 41 is shown which determines the operating state of the vehicle (engine 4 ) based on the cycle signal t from the engine revolution cycle measurement circuit 17 and the accelerator pedal travel signal a from the accelerator pedal path -Measurement circuit 26 determines, a selection circuit 42 selects one of the first and second operation sections 28 and 29 based on the output signal of the acceleration deceleration / travel determination circuit 41 , a first switch circuit SW1 selectively connects the microphone 10 to the first operation section 28 or the second operation section 29 , under the control of the selection circuit 42 , and a second switch circuit SW2 selectively connects the first operation section 28 or the second operation section 29 to the speaker 11 , under the control of the selection circuit 42 . When the first switch circuit SW1 connects the terminal 0 to the terminal 1 , the microphone 10 is connected to the first operation section 28 and the vibration signal m1 is input to the first operation section 28 . When the first switch circuit SW1 connects the terminal 0 to the terminal 2 , the microphone 10 is connected to the second operation section 29 and the vibration signal m2 is input to the second operation section 29 . When the second switch circuit SW2 connects the terminal 0 to the terminal 1 , the first operation section 28 is connected to the speaker 11 and the first control signal S1 is output to the speaker 11 . When the second switching circuit SW2 connects the terminal 0 to the terminal 2 , the second operation section 29 is connected to the speaker 11 and the second control signal s2 is output to the speaker 11 .

In the first embodiment, the engine revolution cycle measuring circuit 17 , the accelerator travel measuring circuit 26 , the vehicle speed measuring circuit 27, and the acceleration deceleration / travel determination circuit 41 constitute the aforementioned environmental condition detecting means that detects the operational state of the vehicle, that is, whether the vehicle is accelerating (or decelerating) or the vehicle is traveling at a constant speed. Furthermore, the acceleration deceleration / travel determination circuit 41 and the first and the second switching circuits SW1 and SW2 constitute the aforementioned selection means.

Of the signal processing operations performed by the controller 16 , the operation of switching the first operation section 28 and the second operation section 29 will be described with reference to the flowchart shown in FIG. 6. First, the engine revolution cycle t (n) at time n is input based on the cycle signal t from the engine revolution cycle measuring circuit 17 (step S1). Then, the degree of change Δt of the engine revolution cycle is calculated in the acceleration deceleration / travel determination circuit 41 based on the absolute value of the difference between the engine revolution cycle t (n) at time n and the engine revolution cycle t (n-1) at time n-1 (Δt = | t (n) -t (n-1) |) (step S2). The amount of change .DELTA.t is compared with a predetermined threshold value Lt in step S3, and when it is determined that it is not smaller than the latter, it is determined that the engine 4 or the vehicle is accelerating or decelerating and the counter k is set to an initial value K in step S4. Then, in step S5, both switch circuits SW1 and SW2 are caused to connect the terminal 0 to the terminal 1 , so that the microphone 10 and the speaker 11 are connected to the first operation section 28 . Finally, the first operation section 28 is turned on and the second operation section 29 is turned off (step S6).

On the other hand, if it is determined in step S3 that the amount of change .DELTA.t is smaller than the predetermined threshold value Lt, it is determined in step S7 whether the counter k is greater than 0. If it is determined that the counter k is greater than 0 , Steps S5 and S6 are executed after the counter k is decremented by 1 in step S8. When the counter k becomes 0, both switching circuits SW1 and SW2 are caused to connect terminal 0 to terminal 2 , so that the microphone 10 and the speaker 11 are connected to the second operation section 29 (step S9). Finally, the first operation section 28 is turned off and the second operation section 29 is turned on (S10).

Thus, in this embodiment, the environment is detected Stand detection device, whether the vehicle is accelerating (or delayed) (as the operating state of the driving stuff), namely to that shown in steps S1 to S3 Wise.

Furthermore, the selector selectively turns on one of the first and second operation sections 28 and 29 in accordance with the operating state of the vehicle, which is detected by the environmental state detection means, in the manner shown in steps S4 to S10. When it is detected that the vehicle is running, the selector turns on the second operation section 29 a predetermined time T (the time required for the counter k to be decremented from the initial value K to 0) after the detection.

The following is the operation of the first embodiment described.

While the vehicle is operating, the ignition signal of the engine 4 is input to the controller 16 and the engine revolution cycle is measured by the engine revolution cycle measuring circuit 17 . At the same time, the reference signal generator 18 generates a reference signal r corresponding to the vibration of the engine. The cycle signal t and the reference signal r are input to the control operation section 22 . Furthermore, the vehicle vibration in the predetermined position in the passenger compartment 3 is detected by the microphone 10, and the output signal m of the microphone 10 is also input to the control operation section 22 . The control operation section 22 generates a control signal s for attenuating the vehicle vibration detected by the microphone 10 . The control signal s is output to the loudspeaker 11 , which generates a vibration in accordance with the control signal s. The vibration generated by the loudspeaker 11 and the vibration caused by the vibration of the motor 4 cancel each other out, as a result of which the vibration detected by the microphone 10 is damped.

In the controller 16 , as shown in FIG. 7, the operational state of the vehicle is determined by comparing the amount of change Δt in the engine revolution cycle with the threshold value Lt in the acceleration-deceleration / travel determination circuit 41 and one of the first or second operation section 28 and 29 of the control operation section 22 is selected in accordance with the determined or determined operating state of the vehicle. That is, when the amount of change Δt in the engine revolution cycle is larger than the threshold value Lt and when it is determined that the vehicle is accelerating or decelerating, the microphone 10 and the speaker 11 are both connected to the first operation section 28 , and through the switch circuits SW1 and SW2. At the same time, the first operation section 28 is turned on while the second operation section 29 is turned off. In this state, the first operation section 28 receives the output signals from the reference signal generator 18 and the microphone 10, and the first control signal s1 is generated by processing the reference signal r such that the vibration detected by the microphone 10 is damped. The first control signal s1 is output to the speaker 11 , which generates a vibration corresponding to the first control signal s1. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 cancel each other, thereby dampening the vibration detected by the microphone 10 .

That is, when the vehicle accelerates or decelerates and the vibration in the passenger compartment 3 is in an uneven condition, the first operation section 28 is caused to operate, and accordingly, a quick response can be made the control on changes in Vi bration in the passenger compartment 3 can be guaranteed.

On the other hand, if the amount of change Δt in the engine revolution cycle is not larger than the threshold value Lt and it is determined that the vehicle is traveling at a constant speed, the first operation section 28 is left on until the predetermined time T after the detection of the steady running of the vehicle expires. When the predetermined time T expires, both the microphone 10 and the speaker 11 are connected to the second operation section 29 by the switching circuits SW1 and SW2. At the same time, the second operation section 29 is turned on while the first operation section 28 is turned off. In this state, the vibration energy on the speaker 11 is adjusted and the output signal on the speaker 11 is corrected based on the output signal m1 from the microphone 10 and the transmission characteristics between the microphone 10 and the speaker 11 to generate a second control signal s2. The second control signal s2 is output to the loudspeaker 11 , which generates a vibration in accordance with the second control signal s2. The vibration generated by the loudspeaker 11 and the vibration caused by the vibration of the motor 4 cancel each other out, whereby the vibration detected by the microphone 10 is damped.

Thus, when the vehicle is traveling at a constant speed and the vibration in the passenger compartment 3 is in a steady state, the second operation section 29 is caused to operate, and accordingly, the entire vibration in the passenger compartment 3 can be sufficiently damped without increasing the amount to be performed Calculation effort.

That is, in the first embodiment, one of the first and second operation sections 28 and 29 is selectively used according to the operation state of the vehicle. Accordingly, satisfactory vibration damping can be obtained regardless of the operating condition of the vehicle.

Since the second operation section 29 is not caused to work, and the first operation section 28 is left in operation until the predetermined time T expires after the detection of the smooth running of the vehicle, the response to the control is kept high, until the operating state of the vehicle is stabilized.

In the first embodiment, it is detected whether the vibration in the passenger compartment (the object of control) in the steady or steady state, namely by whether the vehicle is running at a constant speed speed drives.

In the second embodiment of the present invention, which will be described below, it is detected whether the vibration in the passenger compartment (the object of the controller) is in the uniform state, via the state of a predetermined vibration on the vehicle body 1 .

Fig. 8 is a view showing a vehicle of the present invention is provided with a vibration damping system according approximate shape of the second exporting. In Fig. 8 those parts similar to Fig. 1 are given the same reference numerals and are not described in detail below.

The vibration damping system of the second embodiment mainly differs from that of the first embodiment in that a floor vibration detector 50 is provided on a floor panel of the passenger compartment 3 to detect the vibration of the floor, and the detection signal of the floor vibration detector 50 becomes entered into the control device 16 . That is, in the first embodiment, the operational state of the vehicle (acceleration-deceleration / smooth running) is detected based on the signals in the engine control unit 9, and one of the first and second operation sections 28 and 29 is selected based on the detection, whereas in FIG second embodiment, a predetermined vibration on the vehicle body (vibration of the floor) is detected by the floor vibration detector 50 , and one of the first and second operation sections 28 and 29 is selected based on the detection by the floor vibration detector 50 .

Fig. 9 shows the structure of the controller 16 in the second embodiment. In FIG. 9, those parts that are analogous to FIG. 2 are provided with the same reference numbers and are not described in detail. The control device 16 of this embodiment mainly differs from that of the first embodiment in that the Erfas p sungssignal the floor vibration detection unit 50 in the control operation section 22 of the signals instead of a and b of the accelerator pedal travel measuring circuit 26 and the vehicle is input speed measuring circuit 27 .

Fig. 10 shows the structure of the control operation section 22 in this embodiment. The control operation section 22 in this embodiment mainly differs from that in the first embodiment in that a vibration condition determination circuit 51 is provided which detects the condition of the vibration of the floor based on the detection signal p of the floor vibration detector 50 and a selection circuit 52 that selects one of the first and second operation sections 28 and 29 based on the output signal of the vibration state determination circuit 51 .

As shown in FIGS. 9 and 10, the environmental condition detection device in this embodiment is constituted by the floor vibration detection device 50 and the vibration condition determination circuit 51 . The vibration state determination circuit 51 determines whether the vibration of the floor of the passenger compartment 3 is in the uniform state. Further, the selector is formed by the selection circuit 52 and the switching circuits SW1 and SW2, and selects one of the first and second operation sections 28 and 29 based on the condition of the vibration of the floor, which is detected by the environmental condition detecting device.

Of the signal processing operations performed by the controller 16 in the second embodiment, the operation of switching the first operation section 28 and the second operation section 29 will be described with reference to the flowchart shown in FIG. 11. First, a ground acceleration p (n) at time n is input based on the ground acceleration signal p (step T1). Then, the measure of the change Δp in the ground acceleration in the vibration condition determination circuit 51 is calculated based on the absolute value or the amount of the difference between the ground acceleration p (n) at time n and the ground acceleration p (n-1) Time n-1 (Δt = | p (n) -p (n-1) |) (step T2). The amount of change Δp is compared with a predetermined threshold Lp in step T3, and if it is determined that it is not smaller than the latter, it is determined that the vibration of the floor of the passenger compartment 3 is in a non-uniform state, that is, the The change in vibration in the passenger compartment floor is large, and the counter k is set to an initial value K in step T4. Then, in step T5, both switch circuits SW1 and SW2 are made to connect terminal 0 to terminal 1 , so that the microphone 10 and the speaker 11 are connected to the first operation section 28 . Finally, the first operation section 28 is turned on and the second operation section 29 is turned off (step T6).

On the other hand, when it is determined in step T3 that the amount of change Δp is smaller than the predetermined threshold Lp, that is, when the vibration of the cabin floor is in the uniform state, it is determined in step T7 whether the counter k is greater than 0. If it is determined that the counter k is larger than 0, steps T5 and T6 are carried out after the counter k is decremented by 1 in step T8. When the counter k becomes 0, both switch circuits SW1 and SW2 are caused to connect terminal 0 to terminal 2 , so that the microphone 10 and the speaker 11 are connected to the second operation section 29 (step T9). Finally, the first operation section 28 is turned off and the second operation section 29 is turned on (step T10).

Thus, in this embodiment, the environmental state detecting means detects the state of vibration in the passenger compartment 3 via the amount of change Δp in the vibration (acceleration) p of the passenger compartment floor in the manner as shown in steps T1 to T3.

Furthermore, the selector selectively turns on one of the first and second operation sections 28 and 29 in accordance with the state of vibration in the passenger compartment 3 , which is detected by the environmental state detecting means in the manner as shown in steps T4 to T10. When it is detected that the vibration of the passenger compartment floor is in the uniform state, the selector switches the second operation portion 29 for a predetermined time T (the time required for the counter k to be decremented from the initial value K to 0) ) after the entry.

The operation of the second embodiment is as follows described.

While the vehicle is running, the ignition signal of the engine 4 is input to the controller 16, and the engine revolution cycle is measured by the engine revolution cycle measuring circuit 17 . At the same time, he generates the reference signal generator 18 a reference signal r corresponding to the vibration of the engine. The cycle signal t and the reference signal r are input to the control operating section 22 . Furthermore, the vehicle vibration in the predetermined position in the passenger compartment 3 is detected by the microphone 10, and the output signal m of the microphone 10 is also input to the control operation section 22 . The control operation section 22 generates a control signal s for damping the vehicle vibration detected by the microphone 10 . The control signal s is output to the loudspeaker 11 , which generates a vibration in accordance with the control signal s. The vibration generated by the loudspeaker 11 and the vibration caused by the vibration of the motor 4 mutually cancel each other out, whereby the vibration detected by the microphone 10 is damped.

In the control device 16 , as shown in FIG. 12, the state of the vibration of the passenger compartment floor is determined by comparing the amount of change Δp in the acceleration or vibration of the cabin or passenger compartment floor by the floor vibration detection device 50 with the threshold value Lp in the vibration condition determination circuit 51 and one of the first and second operation sections 28 and 29 of the control operation section 22 is selected in accordance with the determined condition of the vibration of the cabin floor. That is, when the amount of change Δp is larger than the threshold Lp and it is determined that the vibration of the passenger compartment floor is in a non-uniform state, the microphone 10 and the speaker 11 are both connected to the first operation section 28 by the switching circuits SW1 and SW2 connected. At the same time, the first operation section 28 is turned on, while the second operation section 29 is turned off. In this state, the first operation section 28 receives the output signals from the reference signal generator 18 and the microphone 10, and the first control signal s1 is generated by processing the reference signal r such that the vibration detected by the microphone 10 is damped. The first control signal s1 is output to the loudspeaker 11 , which generates a vibration in accordance with the first control signal s1. The vibration generated by the loudspeaker 11 and the vibration caused by the vibration of the motor 4 cancel each other, whereby the vibration detected by the microphone 10 is damped.

That is, when the vibration of the cabin floor is in a non-uniform state, which indicates that the vibration in the cabin 3 is in a non-uniform state, the first operation section 28 is caused to operate, and accordingly, a quick response can be made. a quick response or a quick control response to changes in the vibration in the passenger compartment 3 can be guaranteed.

On the other hand, if the amount of change Δp is not larger than the threshold Lp and it is determined that the vibration of the cabin floor is in the uniform state, the first operation section 28 is left on until the predetermined time T after the detection of the uniform state Vibration of the passenger compartment floor expires. When the predetermined time T elapses, the microphone 10 and the speaker 11 are both connected to the second operation section 29 by the switching circuits SW1 and SW2. At the same time, the second operation section 29 is turned on while the first operation section 28 is turned off. In this state, the vibration energy at the speaker 11 is set and the output signal at the speaker 11 is corrected based on the output signal m1 from the microphone 10 and the transmission characteristics between the microphone 10 and the speaker 11 to a second control signal to generate s2. The second control signal s2 is output to the speaker 11 , which generates a vibration corresponding to the second control signal s2. The vibration generated by the loudspeaker 11 and the vibration caused by the vibration of the motor 4 mutually cancel each other, whereby the vibration detected by the microphone 10 is damped.

Thus, when the vibration of the cabin floor is in the uniform state, which indicates that the vibration in the cabin 3 is in the uniform state, the second operation portion 29 is caused to operate, and accordingly, the entire vibration in the cabin can 3 are dampened satisfactorily without increasing the computational effort.

That is, in the second embodiment, one of the first and second operation sections 28 and 29 is selectively used according to the state of vibration in the passenger compartment 3 , which is detected via the state of vibration of the passenger compartment floor, and accordingly, satisfactory vibration damping can be obtained independently to the state of the vibration in the passenger compartment 3 .

A third embodiment of the present invention will now be described below. The third embodiment is substantially the same as the second embodiment except that one of the first and second operation sections 28 and 29 is selectively used according to whether the vibration of the cabin floor rises, although in the second embodiment, one of the first and second operation section 28 and 29 is selectively used according to whether the vibration of the cabin floor is in the steady state or in the non-uniform state.

That is, in the third embodiment detects the ambient condition detecting means, which is formed by the Bodenvibra tion detecting means 50 and the Vibrationszustand- determination circuit 51 determines whether the vibration of the passenger cell bottom increases.

Of the signal processing operations performed by the control device 16 in the third embodiment, the operation of switching the first operation section 28 and the second operation section 29 will be described with reference to the flowchart shown in FIG. 13. First, a ground acceleration p (n) at time n is input based on the ground acceleration signal p (step U1). Then the absolute value | p | the present or current ground acceleration p (n) is compared with a predetermined threshold value Lp in step U2 and if it is determined that it is not greater than the last re, it is determined that the vibration of the floor of the passenger compartment 3 does not increase, and a counter k is set to an initial value K in step U3. Then, in step U4, the switching circuits SW1 and SW2 are both caused to connect the terminal 0 to the terminal 1 , so that the microphone 10 and the speaker 11 are connected to the first Operationsab 28 . Finally, the first operation section 28 is turned on and the second operation section 29 is turned off (step U5).

On the other hand, if it is determined in step U2 that the absolute value | p | the current floor vibration or floor acceleration p (n) is greater than the predetermined threshold value Lp, ie if the vibration of the passenger compartment floor increases, it is determined in step U6 whether the counter k is greater than 0. If it is determined that If the counter k is greater than 0, steps U4 and U5 are carried out after the counter k is decremented by 1 in step U7. When the counter k becomes 0, the switching circuits SW1 and SW2 are both caused to connect port 0 to port 2 , so that the microphone 10 and the speaker 11 are connected to the second operation section 29 (step U8). Finally, the first operation section 28 is switched off and the second operation section 29 is switched on (step U9).

Thus, in this embodiment, the environmental condition detection device detects the state of vibration in the passenger compartment 3 via the absolute value or amount | p | the vibration p of the passenger compartment floor in the manner shown in steps U1 and U2.

Furthermore, the selection device selectively switches on one of the first and second operating sections 28 and 29 in accordance with the state of the vibration of the passenger compartment floor, that is to say the state of the vibration in the passenger compartment 3 , which is detected by the ambient state detection device, to that in steps U3 to U9 shown way. When it is determined that the vibration of the cabin floor does not rise, the selector turns on the first operation section 28 , whereas when it is detected that the vibration of the cabin floor increases, the selector switches the second operation section 29 a predetermined time T (the time required for the counter k in order to be decremented from the initial value K to 0) after the detection.

The following is the operation of the third embodiment described.

While the vehicle is running, the ignition signal of the engine 4 is input to the controller 16 and the engine revolution cycle is measured by the engine revolution cycle measuring circuit 17 . At the same time, the reference signal generator 18 generates a reference signal r corresponding to the vibration of the engine. The cycle signal t and the reference signal r are input to the control operation section 22 . Furthermore, the vehicle vibration in the predetermined position in the passenger compartment 3 is detected by the microphone 10, and the output signal m of the microphone 10 is just entered if in the control operation section 22 . The control operation section 22 generates a control signal s for attenuating the vehicle vibration detected by the microphone 10 . The control signal s is output to the loudspeaker 11 , which generates a vibration in accordance with the control signal s. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 cancel each other, thereby dampening the vibration detected by the microphone 10 .

In the control device 16 , as shown in FIG. 14, the state of the vibration of the passenger compartment floor is determined by comparing the absolute value | p | Be the acceleration or vibration p of the passenger compartment floor, which is detected by the floor vibration detection means 50 , with the threshold value Lp in the vibration condition detection circuit 51 and one of the first and second operation sections 28 and 29 of the control operation section 22 is selected according to the state according to the detected condition of the vibration of the cabin floor. That is, if the absolute value | p | is not greater than the threshold value Lp and if it is determined that the vibration of the passenger compartment floor does not rise, the microphone 10 and the loudspeaker 11 are both connected to the first operating section 28 by the switching circuits SW1 and SW2. At the same time, the first operation section 28 is turned on, while the second operation section 29 is turned off. In this state, the first operation section 28 receives the output signals from the reference signal generator 18 and the microphone 10, and the first control signal s1 is generated by processing the reference signal r so as to dampen the vibration detected by the microphone 10 . The first control signal s1 is output to the loudspeaker 11 , which generates a vibration corresponding to the first control signal s1. The vibration generated by the loudspeaker 11 and the vibration caused by the vibration of the motor 4 mutually cancel each other, whereby the vibration detected by the microphone 10 is damped.

That is, if the vibration of the passenger compartment floor does not rise, which indicates that there is not the case in which the level of the vibration in the passenger compartment 3 , which is to be controlled, rises substantially over the entire frequency range, or the case exists, at which a certain component of the vibration detected by the microphone 10 becomes particularly high, the certain vibration component is used as the object of the control, and the first operation section 28 is caused to work, and accordingly, a satisfactory vibration damping effect can be obtained, while ensuring a quick control response to changes in vibration in the passenger compartment 3 .

On the other hand, if the absolute value | p | is larger than the threshold value Lp and it is determined that the vibration of the passenger compartment floor increases, the first operation section 28 is left on until the predetermined time T expires after the detection of the state in which the vibration of the passenger compartment floor increases. When the predetermined time T expires, both the microphone 10 and the speaker 11 are connected to the second operation section 29 by the switching circuits SW1 and SW2. At the same time, the second operation section 29 is turned on while the first operation section 28 is turned off. In this state, the vibration energy is set to the speaker 11 and the output signal to the speaker 11 is corrected based on the output signal m1 from the microphone 10 and the transmission properties between the microphone 10 and the speaker 11 to a second control signal s2 The second control signal s2 is output to the loudspeaker 11 , which generates a vibration corresponding to the second control signal s2. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 mutually cancel each other, whereby the vibration detected by the microphone 10 is damped.

Thus, if the vibration of the cabin floor is in an increasing state, which indicates that the vibration in the cabin 3 rises substantially over the entire frequency range, the second operation section 29 is caused to operate, and accordingly, all the vibration in the cabin can 3 can be dampened satisfactorily without the calculation effort to be increased.

Thus, in the third embodiment, one of the first and second operation sections 28 and 29 is selectively used in accordance with the state of vibration in the passenger compartment 3 that is detected and the state of the vibration in the passenger compartment floor, and accordingly, satisfactory vibration damping can be obtained regardless of the state of vibration in the passenger compartment 3 .

It may be considered that in the third embodiment, it is determined according to the acceleration of the passenger compartment floor whether the vibration in the passenger compartment 3 rises over the entire frequency range. However, whether the vibration in the passenger cell 3 rises over the entire frequency range can also be determined directly by analyzing the vibration in the passenger cell 3 by means of frequency bands by using an analyzer with fast Fourier transformation (FFT).

Whether the vibration in the passenger compartment 3 rises over the entire frequency range can further be determined indirectly on the basis of various information from electrical instruments or the like which are mounted on the vehicle body.

A fourth embodiment of the present invention will now be described, in which it is indirectly detected, based on information from various electronic instruments or measuring devices or the like mounted on the vehicle body, whether the vibration in the passenger cell 3 increases over the entire frequency range.

Fig. 15 is a block diagram showing the structure of the controller 16, which in the vibration damping system of the fourth embodiment of the present invention is used in accordance with, and FIG. 16 is a block diagram showing the structure of the control operation section 22 shown in Fig. 15 can be seen.

In this embodiment, as shown in FIG. 15, an information signal i from a predetermined electronic instrument of the vehicle is input to the control operation section 22 . Specifically, the information signal i is input to a vibration state determination circuit 61 ( FIG. 16) in the control operation section 22 . The vibration state determination circuit 61 determines whether the vibration in the passenger compartment 3 rises over the entire frequency range, based on the information signal i. Normally, the first operation section 28 is selected and the first operation section 28 is left on, leaving the second operation section 29 off, and when a condition in which the vibration in the passenger compartment 3 rises over the entire frequency range is detected, the second operation section 29 is turned on and the first operation section 28 is turned off.

The electronic instruments that can be used as the information source 60 are as follows, and on which information the vibration condition determination circuit 61 determines that the vibration in the passenger compartment 3 increases over the entire frequency range is listed below for each electronic instrument.

• 1) In the case where the electronic instrument 60 is an electronic control unit for controlling the engine:
  • a) When the vibration state determination circuit 61 receives information that the lean combustion control of the engine is effected (fuel is injected in an amount that makes the air / fuel ratio leaner than the stoichiometric ratio).
  • b) When the vibration condition determination circuit 61 receives information that exhaust gas recirculation control is effected.
  • c) When the vibration state determination circuit 61 receives information that an electronic ignition timing control is effected.
  • d) When the vibration condition detection circuit 61 receives information that fuel is injected without feedback control or air / fuel ratio control after the engine is warmed up.
  • e) When the vibration condition detection circuit 61 receives information that a purge control (gas of fuel in the upper part of the fuel tank is adsorbed and introduced into the engine) is effected.
  • f) When the vibration state determination circuit 61 receives information that an idle speed control is effected.
  • g) When the vibration condition detection circuit 61 receives information that the engine speed is high.
  • h) When the vibration condition determination circuit 61 receives information that the accelerator pedal is fully depressed.
  • i) When the vibration condition detection circuit 61 receives information that the engine brake is operating.
  • j) When the vibration condition detection circuit 61 receives information that the engine is operating under a heavy load.
  • k) When the vibration condition detection circuit 61 receives information that the turbocharger is operating.
  • l) When the vibration condition detection circuit 61 receives information that the supercharger is operating.
  • m) When the vibration condition determination circuit 61 receives information that the vehicle is running.
• 2) In the event that the electronic instrument 60 is an electronic automatic transmission control unit:
  • a) When the vibration condition detection circuit 61 receives information that the automatic transmission is switched.
  • b) When the vibration condition detection circuit 61 receives information that the automatic transmission is locked.
  • c) When the vibration state determination circuit 61 receives information that the automatic transmission is controlled by slip (the automatic transmission is locked, a predetermined amount of slip or a certain amount of slip being permitted between the opposite clutch and the torque converter jacket or the torque converter cover). .
  • d) When the vibration condition determination circuit 61 receives information that the automatic transmission is in the P range or in the N range.
• 3) The case where the electronic instrument 60 is an active suspension control unit:
  • a) When the vibration condition detection circuit 61 receives information that the front wheels of the vehicle have run over a bump on the road.
  • b) When the vibration condition determination circuit 61 receives information that the vehicle is running on a rough road surface.
  • c) When the vibration condition determination circuit 61 receives information that the vehicle is provided with temper tires.
• 4) In the event that the electronic instrument 60 is a four-wheel steering control unit:
  • a) When the vibration condition detection circuit 61 receives information that the rear wheels are rotated in the same direction as the front wheels.
• 5) In the event that the electronic instrument 60 is an anti-lock braking system control unit:
  • a) When the vibration condition detection circuit 61 receives information that the anti-lock braking system is operating.
• 6) In the event that the electronic instrument 60 is a traction control unit:
  • a) When the vibration condition detection circuit 61 receives information that the traction control system is operating.
• 7) In the event that the electronic instrument 60 is a climate control unit:
  • a) When the vibration condition detection circuit 61 receives information that the air conditioner is operating.
  • b) When the vibration condition determination circuit 61 receives information that the temperature of the engine coolant is low while the engine is operating.
• 8) In the event that the electronic instrument 60 is a navigation system control unit that provides the vehicle or the driver with road or road information based on a signal from an artificial satellite:
  • a) When the vibration condition detection circuit 61 receives information that the vehicle is traveling on a rough road, through a tunnel or through highlands.
• 9) In the event that the electronic instrument 60 is a road-to-vehicle communication unit that presents the vehicle with road information about the communication therebetween:
  • a) When the vibration condition detection circuit 61 receives information that the vehicle is traveling on a rough road, through a tunnel or through the highlands.
• 10) In the case that the electronic instrument 60 is a lamp control unit that controls the lights of the vehicle according to the lighting or the brightness outside the vehicle or the like:
  • a) When the vibration condition detection circuit 61 receives information that the headlights of the vehicle are on, which indicates that the vehicle is traveling through a tunnel.
• 11) In the event that the electronic instrument 60 is an AV instrument control unit:
  • a) When the vibration condition detection circuit 61 receives information that the volume of the AV instrument (an audiovisual device) is high.
• 12) In the event that the electronic instrument 60 is a torque split control unit:
  • a) When the vibration condition detection circuit 61 receives information that the driving torque of the engine is transmitted to the four wheels.

The electronic instrument 60 is not limited to the instruments described above, and the information on the basis of which the vibration condition determination circuit 61 determines that the vibration in the passenger compartment 3 rises over the entire frequency range is not limited to those described above.

That the vehicle travels over a rough road surface can, for. B. also about information from the active suspension tax unit, the traction control unit and the anti-lock braking system Control unit can be detected.

In the fourth embodiment, if it is determined on the basis of the information signal i from the electronic instrument 60 that there is not the case where the level of vibration in the passenger compartment 3 increases substantially over the entire frequency range, the microphone 10 and the Loudspeaker 11 both connected to the first operating section 28 via the switching circuits SW1 and SW2. At the same time, the first operation section 28 is turned on while the second operation section 29 is turned off. In this state, the first operating state 28 receives the output signals from the reference signal generator 18 and the microphone 10 and the first control signal s1 is generated by processing the reference signal r in such a way that a specific component of the vibration detected by the microphone 10 is damped. The first control signal s1 is output to the speaker 11 , which generates a vibration corresponding to the first control signal s1. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 mutually cancel each other, whereby the vibration, which is detected by the microphone 10 , in the predetermined position in the cabin 3 , is damped.

That is, if there is not the case in which the level of vibration in the cabin 3 or the passenger compartment 3 to be controlled rises substantially over the entire frequency range, or the case in which a certain component is present the vibration detected by the microphone takes a particularly high level, and the particular vibration component is used as the object of the controller, and the first operation section 28 is caused to operate, and accordingly, a satisfactory vibration damping effect can be determined by damping the be Component can be obtained.

On the other hand, if it is determined that there is a case where the level of vibration in the cabin 3 increases substantially over the entire frequency range, the first operation section 28 is left on until the predetermined time T expires after the detection of that state . When the predetermined time T elapses, the microphone 10 and the speaker 11 are both connected to the second operation section 29 by means of the switching circuits SW1 and SW2. At that time, the second operation section 29 is turned on while the first operation section 28 is turned off. In this state, the vibration energy to the speaker 11 is adjusted and the output signal to the speaker 11 is corrected based on the output signal m1 from the microphone 10 and the transmission characteristics between the microphone 10 and the speaker 11 to generate a second control signal s2 . The second control signal s2 is output to the loudspeaker 11 , which generates a vibration in accordance with the second control signal s2. The vibration generated by the loudspeaker 11 and the vibration caused by the vibration of the motor 4 cancel each other out, where the vibration in the passenger compartment 3 dampens.

Thus, if the vibration in the passenger compartment 3 rises substantially over the entire frequency range, the second operation section 29 is caused to operate, and accordingly, the entire vibration in the passenger compartment 3 can be satisfactorily damped without increasing the computational effort to be performed.

That is, in the fourth embodiment, one of the first and second operation sections 28 and 29 is selectively used in accordance with the state of vibration in the passenger compartment 3 , which is indirectly detected from information from the electronic instrument 60 , and accordingly, satisfactory vibration damping can be independent can be obtained from the state of vibration in the passenger compartment 3 .

A fifth embodiment of the present invention will now be described, in which it is determined indirectly on the basis of the state of a calculation in the operation sections whether the vibration in the passenger compartment 3 rises over the entire frequency range.

FIG. 17 is a block diagram showing the structure of the control device 16 used in the vibration damping system according to the fifth embodiment of the present invention, and FIG. 18 is a block diagram showing a structure of the control operation section 22 shown in FIG. 17 see is.

As shown in FIG. 17, the controller 16 in this embodiment is substantially the same as that shown in FIG. 2 except that it does not have an accelerator pedal travel measuring circuit 26 and a vehicle speed measuring circuit 27 is provided, and that the structure of the control 36084 00070 552 001000280000000200012000285913597300040 0002004333145 00004 35965 operation section 22 differs from that shown in FIG .

As shown in FIG. 18, the control operation section 22 in this embodiment includes a calculation state detection circuit 71 which detects the state of the vibration signal m input from the microphone 10 in the control operation section 22 as the state that represents the state of the calculation in the first and second operation sections 28 and 29 , and a selection circuit 72 that selects one of the first and second operation sections 28 and 29 based on the output signal of the calculation state detection circuit 71 ; which represents the state of the calculation in the first and second operation sections 28 and 29 .

In this embodiment, the environmental condition detection means is constituted by the microphone 10 and the calculation condition detection circuit 71 , and indirectly detects whether the vibration in the passenger compartment 3 rises over the entire frequency range by detecting the condition of the vibration signal m.

Of the signal processing operations performed by the controller 16 in the fifth embodiment, the operation of switching the first operation section 28 and the second operation section 29 will be described with reference to the flowchart shown in FIG. 19. First, a vibration signal m (n) at time n is calculated based on the vibration signal m from the microphone 10 (step V1). Then, the amount of change Δm in the vibration signal m is calculated based on the absolute value of the difference between the vibration signal m (n) at time n and the vibration signal m (n-1) at time n-1 (Δm = | m (n) -m (n-1) |) (step V2). The amount of change Δm is compared with a predetermined threshold value Lm in step V3, and if it is determined that the former value is not larger than the latter, it is determined that there is not the case where the vibration in the passenger compartment 3 rises over the entire frequency range, and a counter k is set to an initial value K in step V4. Then in step V5 both switch circuits SW1 and SW2 are caused to connect terminal 0 to terminal 1 , so that the microphone 10 and the loudspeaker 11 are connected to the first operating section 28 . Finally, the first operation section 28 is turned on and the second operation section 29 is turned off (step V6).

On the other hand, if it is determined in step V3 that the amount of change Δm is smaller than the predetermined threshold value Lm, that is, if it is determined that there is a case where the vibration in the passenger compartment 3 increases over the entire frequency range, it will in step V7 determines whether the counter k is greater than 0. If it is determined that the counter k is greater than 0, steps V5 and V6 are carried out after the counter k is decremented by 1 in step V8. When the counter k becomes 0, the switching circuits SW1 and SW2 are both caused to connect terminal 0 to terminal 2 , so that the microphone 10 and the speaker 11 are connected to the second operation section 29 (step V9). Finally, the first operation section 28 is turned off and the second operation section 29 is turned on (step V10).

Thus, in this embodiment, the environmental condition detection means detects whether the vibration in the passenger compartment 3 increases over the entire frequency range, based on the change in the amount of the change Δm of the vibration signal m to that shown in steps V1 to V3 Wise.

Furthermore, the selector selectively turns on one of the first and second operation sections 28 and 29 in accordance with the state of vibration in the passenger compartment 3 detected by the environmental condition detection means in the manner shown in steps V4 to V10. When it is detected that the vibration in the passenger compartment 3 rises over the entire frequency range, the selector switches the second operation section 29 for a predetermined time T (the time required for the counter k to be decremented from the initial value K to 0) ) after recording.

The following is the operation of the fifth embodiment described.

While the vehicle is running, the ignition signal of the engine 4 is input to the controller 16 , and the engine revolution cycle is measured by the engine revolution cycle measurement circuit 17 . At the same time, the reference signal generator 18 generates a reference signal r corresponding to the vibration of the engine. The cycle signal t and the reference signal r are input to the control operation section 22 . Furthermore, the vehicle vibration in the predetermined position in the passenger compartment 3 is detected by the microphone 10 and the output signal m of the microphone 10 is also input to the control operation section 22 . The control operation section 22 generates a control signal s for damping the vehicle vibration detected by the microphone 10 . The control signal s is output to the loudspeaker 11 , which generates a vibration in accordance with the control signal s. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 cancel each other out, where is damped by the vibration detected by the microphone 10 .

In the controller 16 , as shown in Fig. 20, the state of the vibration signal m is detected or determined by comparing the amount of change Δm of the vibration signal m with the threshold value Lm in the calculation state detection circuit 71 and one of the first and second operation section 28 and 29 of the control operation section 22 is selected according to the determined or determined state of the vibration signal m. That is, if the amount of change Δm is not larger than the threshold value Lm and if it is determined that there is not the case where the vibration in the passenger compartment 3 rises over the entire frequency range, both the microphone 10 and the loudspeaker 11 connected to the first operation section 28 through the switching circuits SW1 and SW2. At the same time, the first operation section 28 is switched on, whereas the second operation section 29 is switched off. In this state, the first operation section 28 receives the output signals from the reference signal generator 18 and the microphone 10, and the first control signal s1 is generated by processing the reference signal r so that the specific component of the vibration detected by the microphone 10 is damped. The first control signal s1 is output to the speaker 11 , which generates a vibration in accordance with the first control signal s1. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 cancel each other out, thereby damping the vibration in the predetermined position in the passenger compartment 3 .

That is, if it is not the case where the vibration in the passenger compartment 3 rises over the entire frequency range, the first operation section 28 is caused to operate, and accordingly, a satisfactory vibration damping effect can be obtained by damping the specific component of the vibration in one particularly high level or with a particularly high level.

On the other hand, if the amount of change Δm is larger than the threshold Lm and it is determined that the vibration in the passenger compartment 3 rises over the entire frequency range, the first operation section 28 is left on until the predetermined time T expires after the condition is detected . When the predetermined time T elapses, the microphone 10 and the speaker 11 are both connected to the second operation section 29 by the switching circuits SW1 and SW2. At the same time, the second operation section 29 is turned on while the first operation section 28 is turned off. In this state, the vibration energy to the speaker 11 is adjusted and the output signal to the speaker 11 is corrected based on the output signal m1 from the microphone 10 and the transmission characteristics between the microphone 10 and the speaker 11 to generate a second control signal s2. The second control signal s2 is output to the loudspeaker 11 , which generates a vibration corresponding to the second control signal s2. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 cancel each other out, whereby the vibration detected by the microphone 10 is damped.

Thus, when the vibration in the passenger compartment 3 rises over the entire frequency range, the second operation section 29 is caused to operate, and accordingly, the entire vibration in the passenger compartment 3 can be dampened satisfactorily without increasing the calculation work.

Now a sixth embodiment of the present Invention described.

The vibration damping system of this embodiment is substantially the same as that of the fifth embodiment, except that the structure of the control operation section 22 in this embodiment is different from that of the fifth embodiment as shown in FIG. 21.

As shown in Fig. 21, the control operation section 22 in this embodiment includes a normal / abnormal detection circuit 81 which determines whether the first and second operation sections 28 and 29 operate normally based on predetermined signals thereof. and a selection circuit 82 which selects one of the first and two operating sections 28 and 29 based on the output signal from the normal / abnormal detection circuit 81 which represents whether the first and second operating sections 28 and 29 are operating normally.

In this embodiment, the environmental condition detection circuit is constituted by the normal / abnormal determination circuit 81 .

In this embodiment, the first operation section 28 is normally selected and the first operation section 28 is left on, leaving the second operation section 29 off. In this state, the first operation section 28 receives the output signals from the reference signal generator 18 and the microphone 10, and the first control signal s1 is generated by processing the reference signal r such that the vibration detected by the microphone 10 is damped. The first control signal s1 is output to the speaker 11 , which generates vibration according to the first control signal s1. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 cancel each other, whereby the vibration is damped in the predetermined position in the passenger compartment 3 .

When the normal / abnormal determination circuit 81 determines that the first operation section 28 is not operating normally, the second operation section 29 is selected. That is, the microphone 10 and the speaker 11 are both connected to the second operation section 29 by means of the switch circuits SW1 and SW2. At the same time, the second operation section 29 is turned on while the first operation section 28 is turned off. In this state, the vibration energy to the speaker 11 is adjusted and the output signal to the speaker 11 is corrected based on the output signal m1 from the microphone 10 and the transmission characteristics between the microphone 10 and the speaker 11 to generate a second control signal s2. The second control signal s2 is output to the loudspeaker 11 , which generates a vibration in accordance with the second control signal s2. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 cancel each other out, whereby the vibration in the passenger compartment 3 is damped.

If tion portion of the first Opera thus in the sixth embodiment 28 is normally or is operating normally, the vibration damping control is in sections by the first operation causes 28, whereby satisfactory Vibra obtained tion damping effect, while a good on response behavior of the control and a good Regelan speaking behavior is guaranteed. When the first operation section 28 is abnormal, the vibration damping control is effected by the second operation section 28 , whereby the entire vehicle vibration is damped satisfactorily. Although the first operation section 28 is normally selected in the sixth embodiment, the second operation section 29 may normally be selected while the first operation section 28 is selected in the event of a failure in the second operation section 28 .

Now a seventh embodiment of the present Invention described.

The vibration damping system of this embodiment is substantially the same as that of the fifth embodiment except that the structure of the control operation section 22 in this embodiment is different from that of the fifth embodiment as shown in FIG. 22.

As shown in FIG. 22, the control operation section 22 in this embodiment includes an over-output detection circuit 91 which determines whether the output level of the control signal s sent to the speaker 11 from the first operation section 28 or the second operation section 29 is output, is larger than a predetermined threshold, and a selection circuit 92 which one of the first and second operation sections 28 and 29 based on the output signal of the over-output detection circuit 91 , which determines whether the output level of the control signal s, which to the speaker 11 from the first operation section 28 or the second Ope rationsabschnitt is output 29, is greater than a prior certain threshold value, and a selection circuit 92, which of first and second operation portions 28 and 29 on the basis of the output signal of an excess output He averaging circuit 91 selects.

In this embodiment, the environmental condition detector is constituted by the over-output detection circuit 91 . That is, in this embodiment, the first operation section 28 is normally selected, and when the over-output detection circuit 91 determines that the output level of the control signal s output to the speaker 11 from the first operation section 28 is larger than the predetermined limit the second operation section 29 is selected. In this embodiment, the predetermined limit value is set such that the speaker 11 can generate a vibration represented by the control signal s within its performance as long as the level of the control signal s is not greater than the limit value, although it can be set in different ways.

The operation of switching the first operation section 28 and the second operation section 29 in this embodiment will be described with reference to the flowchart shown in FIG . In this embodiment, usually the first operation section 28 selects out, and then displays in Fig. Flow chart of the operation when the selection circuit 92 switches from the first operation section 28 to the second operation section 29 and if the selection means 92 of the two-th operation section 29 shown 23 to the first Operationsab section 28 switches.

First, a control signal s (n) at time n is input based on the control signal s (more specifically, the first control signal s1) output from the first operation section 28 (step W1). Then the absolute value | s (n) | the output level of the current or present control signal s (n) with the absolute value | Ls | of the predetermined limit value Ls in step W2 and if it is determined that the former is smaller than the latter (| Ls | - | s (n) | <0), it is determined that the output level of the control signal s with respect to the power or Lei performance capability of the speaker 11 is suitable and the switching circuits SW1 and SW2 are both caused to connect to terminal 0 to terminal 1 , so that the microphone 10 and the speaker 11 are connected to the first operation section 28 (step W3). Then, the first operation section 28 is left on and the second operation section 29 is left off (step W4).

On the other hand, if it is determined in step W2 that the former is not smaller than the latter (| Ls | - | s (n) | 0), a counter k is set to an initial value K in step W5. Then, in step W6, the switching circuits SW1 and SW2 are both caused to connect terminal 0 to terminal 2 , so that the microphone 10 and the speaker 11 are connected to the second operation section 29 . Then, the first operation section 28 is turned off and the second operation section 29 is turned on (step W7).

Thereafter, the counter k is decremented by 1 in step W8 and then it is determined in step W9 whether the counter k is greater than 0. If it is determined that the counter k is greater than 0, steps W6 to W8 are repeated. When the counter k becomes 0, steps W3 and W4 are carried out, that is, the first operation section 28 is selected again.

Thus, in this embodiment, the environmental condition detection means detects whether the control signal s output from the first operation section 28 requires the speaker 11 to output power beyond its performance, namely through the absolute value | s (n) | of the control signal s in the manner shown in steps W1 and W2.

Furthermore, the selector normally selects the first operation section 28 , switches to the second operation section 29 when it is determined that the control signal s output from the first operation section 28 requires the speaker 11 to output power beyond its capability, and switches back to the first operation section 28 a predetermined time T (the time required for the counter k to be decremented from the initial value K to 0) after the determination, in the manner shown in steps W4 to W9.

In the seventh embodiment, the first operation section 28 is normally selected. In this state, the first operation section 28 receives the output signals from the reference signal generator 18 and the microphone 10, and the first control signal s1 is generated by processing the reference signal r such that a certain component of the vibration detected by the microphone 10 is damped. The first control signal s1 is output to the speaker 11 , which generates vibration according to the first control signal s1. The vibration generated by the speaker 11 and the vibration caused by the vibration of the motor 4 cancel each other, whereby the vibration detected by the microphone 10 is damped in the predetermined position in the passenger compartment 3 .

Thus, when the output level of the control signal s is not larger than the limit value and the speaker 11 can properly generate the vibration represented by the control signal s, the vibration damping control is effected by the first operation section 28 , whereby a satisfactory vibration damping effect is obtained while good response behavior is guaranteed.

On the other hand, when the level of the control signal s output from the first operation section 28 to the speaker 11 exceeds the limit value Ls and the speaker 11 becomes unable to generate the vibration represented by the control signal s, the first becomes Operation section 28 immediately switched to the second operation section 29 , as shown in FIG. 24. With this arrangement, the entire vibration in the passenger compartment can be dampened satisfactorily while avoiding an undesirable situation in which the speaker 11 is driven to be in a state in which it does not damp the vehicle vibration can generate optimal vibration, and the vibration in the passenger compartment 3 is increased by driving the speaker 11 . The second operation section 29 is switched to the first operation section 28 after the lapse of the predetermined time T.

In the first to seventh embodiments described above, only one of the first and second operation sections 28 and 29 is selectively operated according to the state of the environment of the system. However, the system can be designed such that one of the operation sections 28 and 29 is kept in constant operation and the other is caused to cooperate or operate only when necessary, or even such that both of them operate constantly. Such vibration damping systems are briefly described below.

Fig. 25 is a block diagram showing the structure of the control operation section 22, which is used in an eighth embodiment of the present invention. The control operation section 22 shown in Fig. 25 is substantially the same as that shown in Fig. 3, except that the switch circuits SW1 and SW2 are different from those shown in Fig. 3 and that an operation control circuit 75 instead of the selection circuit 42 is provided. That is, although in the first embodiment, the selection circuit 42 switches the first and second operation sections 28 and 29 according to the determination of the acceleration-deceleration / travel determination circuit 41 , the first operation section 28 is constantly operated in this embodiment and the operation control circuit 75 is caused that the second operation section 29 works together with the first operation section 28 when the need arises, based on the operating state determined by the acceleration-deceleration / trip determination circuit 41 . The states for operating the second operation section 29 together with the first operation section 28 may be the same as those used for selecting the second operation section 29 in the previously described embodiments. It can be seen that the second operation section 29 is left in constant operation, whereas the first operation section 28 is caused to work together with the second operation section 29 if necessary.

Now, a ninth embodiment of the present invention, wherein both the first and second operation sections 28 and 29 are kept in constant operation, will be described with reference to FIG. 26, which shows a structure of the control operation section 22 that is in the ninth embodiment is used.

The control operation section 22 shown in FIG. 26 is substantially the same as that shown in FIG. 3, except that a filter section 55 is provided in place of the first and second switching circuits SW1 and SW2 and a gain adjustment circuit 76 in place of the selection circuit 42 is provided.

In this embodiment, the first and second operation sections 28 and 29 are constantly operated, and the gain adjustment circuit 76 changes the gain of the second operation section 29 according to the operational state of the vehicle, which is determined by the acceleration deceleration / travel determination circuit 41 . The Filterab section 55 has a low-pass filter 56 , which is connected to the first operation section 28 , and a high-pass filter 57 , which is connected to the second operation section 29 , so that only the low-frequency component of the vibration signal m is input into the first operation section 28 and only the high-frequency components of the vibration signal m is entered into the second operation section 29 . Thus, in this embodiment, the first operation section 28 controls the low-frequency components of the vibration and the second operation section 29 controls the high-frequency components of the vibration.

Although in the above-described embodiments Vibration generating device speakers used who that can also be used as the vibration generating device Vibrating engine mounts are used, the engine supports and supports and the engine vibrate or in vibra tion can move. Furthermore, the speaker and the vibrating engine mounting in combination be used.

A tenth embodiment of the present invention will now be described with reference to FIGS. 27 and 28, in which the speaker and the vibrating motor position are used in combination.

FIG. 27 is a block diagram showing the structure of the controller 16 used in the tenth embodiment, and FIG. 28 is a block diagram showing the structure of the control operation section 22 shown in FIG. 27. The control device 16 shown in Fig. 27 is substantially the same as that shown in Fig. 2, except that a vibrating motor mount 12 and a D / A converter 23 a, a low-pass filter 24 a and an amplifier 25 a for the vibrating engine mounting 12 are added. The speaker 11 is used as a vibration generator designed to mainly generate high-frequency vibration, and the vibrating motor mount 12 is used as a vibration generator designed to mainly generate low-frequency vibration.

As shown in FIG. 28, in this embodiment, the selection circuit 77 selects one of the first and second operation sections 28 and 29 according to the operating state of the vehicle, which is determined by the acceleration deceleration / travel determination circuit 41 , and the first and second switching circuits SW1 and SW2 are laid out in such a way that the first operating section 28 controls the vibrating motor mounting 12 and the second operating section 29 controls the loudspeaker 11 . Furthermore, only the low-frequency component of the vibration signal m from the microphone 10 is input into the first operation section 28 and only the high-frequency component of the vibration signal m from the microphone 10 is input into the second operation section 29 , by means of a low-pass filter 43 and a high-pass filter 44 .

Although the present invention has been described in detail above in conjunction has been described with some embodiments, the embodiments can be changed in many ways.

It can e.g. B. according to the state of a calculation in the operation sections, whether the vibration in the passenger compartment 3 is in a uniform state or in a non-uniform state. For example, since the filter factor of the adaptive filter 34 of the first operation section 28 changes less when the vibration in the passenger compartment 3 is in the uniform state, whether the filter factor of the adaptive filter 34 is detected directly or indirectly can be detected Vibra tion in the passenger compartment 3 is in a uniform or in a non-uniform state.

Further, the vibration damping system may be configured to detect whether the calculation in the first operation section 28 is appropriately performed within the operational performance of the first operation section 28 , and the first operation section 28 is selected when the operation is performed appropriately, and otherwise the second operation section 29 is selected.

Although in the above-described embodiments, the switching between the first and second operation sections 28 and 29 is promptly effected by using the first and second switching circuits SW1 and SW2, the switching can be effected gradually. For example, the switching from the first operation section 28 to the second operation section 29 can be effected immediately, while the switching from the second operation section 29 to the first operation section 28 is effected gradually. In contrast, the switch from the first operation section 28 to the second operation section 29 can be effected gradually, while the switch from the second operation section 29 to the first operation section 28 is effected immediately. Furthermore, both the switchover from the first operation section 28 to the second operation section 29 and the switchover from the second operation section 29 to the first operation section 28 can be effected gradually.

Although the operating state in the first embodiment of the vehicle is detected via the change in the engine  rotation cycle, it can also speed over the vehicle speed, the amount of depression of the accelerator pedal or the like chen are recorded.

Furthermore, although in the described embodiment shape the vehicle's vibration source is the engine another vibration which is the vibration of exhaust gas or the Exhaust gas vibration is used as the control object as long as the reference signal from information about the Cycle or the frequency of the vibration can be obtained.

Although, in the above-described embodiments, the second operation section 29 is of the feedback control type as used e.g. B. is disclosed in Japanese Patent Application 4 (1992) -32217, the second operations section 29 may be a control system with optimal feedback, designed by the H∞ control theory. In this case, the arrangement of the second operation section 29 is as shown in FIG. 29. Fig. 29 corresponds to Fig. 5 and a control device K is designed on the basis of the H∞ theory, so that an optimal feedback system is formed by the microphone 10 , the speaker 11 and the second operation section 29th

Claims (13)

1. Vibration damping system for a vehicle, which forms a system that accepts vibration generated in the vehicle as a control object, with:
a reference signal generator ( 18 ) that generates a reference signal (r) based on information about the cycle of a vibration source ( 4 ) that generates a cyclic vibration in the vehicle;
a vibration detector ( 10 ) that detects vibration in a predetermined position in the vehicle and outputs a vibration signal (m);
a vibration generating device ( 11 ; 11 , 12 ) that generates a vibration;
a first operation means (28) receiving the reference signal (r) and the vibration signal (m) from the reference signal generator (18) or the Vi brationserfassungseinrichtung (10) receives a first control signal (s1) generated by processing the reference signal (r) in such a way that the vibration detected by the vibration detection device ( 10 ) is damped and outputs the first control signal (s1) to the vibration generation device ( 11 ; 11 , 12 );
a second operation device ( 29 ), which receives the vibration signal (m) from the vibration detection device ( 10 ), generates a second control signal (s2), which is designed to dampen the vibration detected by the vibration detection device ( 10 ), and the second Control signal (s2) to the Vibrationsgenerationseinrich device ( 11 ; 11 , 12 ) outputs. 2. The vibration damping system according to claim 1, further comprising an environmental condition detection device ( 26 , 27 , 41 ; 50 , 51 ; 60 , 61 ; 10 , 71 ; 81 ; 91 ) that detects the condition of a predetermined factor of the environment of the system detected, and having a selector ( 42 ; 52 ; 62 ; 72 ; 82 ; 92 ) which selectively causes one of the first and second operation means ( 28 , 29 ) to operate in accordance with the state of the predetermined factor of the environment of the system, which is detected by the ambient condition detection device ( 26 , 27 , 41 ; 50 , 51 ; 60 , 61 ; 10 , 71 ; 81 ; 91; ). 3. Vibration damping system according to claim 1 or 2, wherein the second operation device ( 29 ) generates the second control signal (s2) by setting vibration energy for the vibration generating device ( 11 ; 11 , 12 ) on the basis of the vibration detection device ( 10 ) and by correcting the Vibration energy on the basis of the vibration signal (m) and the transmission properties between the vibration detection device ( 10 ) and the vibration generation device ( 11 ; 11 , 12 ). 4. Vibration damping system according to claim 2 or 3, the predetermined factor of the environment of the System is a predetermined vibration, which in the vehicle is generated.   5. Vibration damping system according to claim 2 or 3, the predetermined factor of the environment of the System is the operating state of the vehicle. 6. Vibration damping system according to claim 5, wherein the operating state of the vehicle is whether the vehicle is in a first state in which it accelerates or decelerates, or in a second state in which it runs at constant Ge speed, and wherein the Selector ( 42 ) causes the first operating device ( 28 ) to operate when the environmental condition detector ( 26 , 27 , 41 ) detects that the vehicle is in the first state and causes the second operating device ( 29 ) operates when the environmental condition detector ( 26 , 27 , 41 ) detects that the vehicle is in the second state. 7. Vibration damping system according to one of claims 1 to 6, wherein the selection device ( 42 ; 52 ; 62 ; 72 ; 82 ; 92 ) switches from the first operation device ( 28 ) to the second operation device ( 29 ) a predetermined time (T) after the environmental condition detector ( 26 , 27 , 41 ; 50 , 51 ; 60 , 61 ; 10 , 71 ; 81 ; 91 ) detects that the vehicle is in the second state. 8. Vibration damping system according to claim 2 or 3, wherein the predetermined factor of the environment of the system is the state of a calculation in at least one of the first and second operation means ( 28 , 29 ). 9. Vibration damping system according to claim 2 or 3, wherein the ambient condition detection device ( 91 ) detects an excessive initial state of the first operation device ( 28 ) in which the level of the vibration signal (s1), which from the first operation device ( 28 ) to the vibra tion generating means ( 11 ; 11 , 12 ) is larger than a predetermined value (Ls), and wherein the selecting means ( 92 ) normally causes the first operating means ( 28 ) to operate and causes the second operating means ( 29 ) works instead of the first operation device ( 28 ) when the ambient condition detection device ( 91 ) detects the excessive initial condition of the first operation device ( 28 ). 10. Vibration damping system according to claim 2 or 3, wherein the ambient condition detection means ( 26 , 27 , 41 ; 50 , 51 ) detects a uniform state of the first operation device ( 28 ), in which the control by the first Operationsein device ( 28 ) is uniform , and wherein the selector ( 42 ; 52 ) normally causes the first operation device ( 28 ) to operate and causes the second operation device ( 29 ) to operate in place of the first operation device ( 28 ) when the environmental condition detector ( 26 , 27 , 41 ; 50 , 51 ) the smooth state of the first Operationeinrich device ( 28 ) detected. 11. A vibration damping system according to claim 2 or 3, wherein the predetermined factor of the environment of the system is whether one of the first and second operation means ( 28 , 29 ) is operating normally, and wherein the selection means ( 82 ) causes the others An operation device operates in place of the one operation device when the environmental condition detection device ( 81 ) detects that the one operation device is abnormal while it is operating. The vibration damping system of claim 2 or 3, wherein the predetermined factor of the environment of the system is whether the vibration generated in the vehicle increases substantially over the entire frequency range, and wherein the selector ( 52 ; 62 ; 72 ) normally ver anlaßt that the first operating means (28) operates, and causes the second Opera tion means (29) instead of the first Opera tion means (28) operates when the surrounding environment state detection means (50, 51; 60, 61; 10 , 71 ) detects that the vibration generated in the vehicle increases substantially over the entire frequency range. 13. A vibration damping system according to claim 2 or 3, wherein the predetermined factor of the environment of the system is whether the vibration generated in the vehicle is in a uniform state, and wherein the selector ( 42 ; 52 ) normally causes the first operations means ( 28 ) operates and causes the second operation means ( 29 ) to operate in place of the first operation means ( 28 ) when the environmental condition detection means ( 26 , 27 , 41 ; 50 , 51 ) detects the vibration generated in the vehicle is in a uniform state.