DE10008822A1 - Controlling torque transfer involves driving clutch to at least approximate to torque corrected for deviation of acting, desired or maximum torque from predefined torque - Google Patents

Abstract

The method involves determining at least one parameter describing the operating and/or ambient parameter-dependent deviation of the torque acting on the clutch, a desired torque or a maximum available torque from a predefined torque, determining a corrected clutch torque from the parameter(s) and driving the clutch to at least approximate to the corrected torque. The load can be an air conditioning compressor.

Description

The invention relates to a method for controlling the transfer of torque from a drive member to one Output device in connection with the drive of Motor vehicles.

DE 196 09 878 A1 describes a device with a Automatically controlled clutch for transferring a Coupling torque from one drive element to one Output drive during a start-up process Motor vehicle known. The clutch torque is in accordance with generated by an actuator. One acts on the actuator Control device, which as a signal from the driver Predeterminable load lever position is supplied. According to one Load lever position or the gradient of the load lever movement about the control device and the actuator Clutch torque or engine speed during Coupling process controlled to achieve a desired Acceleration.

During the operation of motor vehicles with the generic method there are deviations of Coupling behavior of the desired coupling behavior, what for example a changing or insufficient one Acceleration behavior during the start-up process Has.

The object of the present invention is therefore undesirable Avoid clutch or starting behavior.  

A procedure for solving this problem shows the measures of Claim 1 on. It has been shown that accordingly Operating parameters and / or environmental parameters at the Drive side of the clutch (maximum) available or acting on the output side of the clutch or especially for the achievement of a desired ) Driving state necessary moment can be different. Thus, is a guarantee of a predefined Approach status or course according to the circumstances adjusted clutch torque required. This realization will according to the invention taken into account in that at least one the drive side or output side of the clutch effective, (maximum) available or necessary Corresponding moment, a deviation of the same from one Setpoint indexing or approximating characteristic value detected becomes. According to the parameter, a corrected Coupling torque determined and, in particular by means of the Actuating control device, under the influence of determined corrected clutch torque the clutch controlled.

The parameter is, for example, at least a discrete, metrologically recorded characteristic value or by one several discrete, chronologically recorded characteristic values composite identification signal or an analog identification signal. A Characteristic can alternatively or additionally from several Characteristic values or characteristic signals composed or determined become. Furthermore, the parameter from the engine control be derived. For example, those with the Characteristics described to act on the clutch moments Partial torques act like one of the driving resistance on the Torque exerted on the output side or by a moment of friction Storage on the input or output side.

At the mentioned moments, especially the engine torque and The moments acting on the clutch are  those at discrete times or moments, especially during the clutch or start-up process.

The control device is, for example a control or regulation unit, a CPU and / or Storage unit. This can be part of the engine management system trained or connected to this. The Control device controls the corresponding control signals Actuators in such a way that (approximately) the determined corrected clutch torque acts on the clutch.

The (functional) connection of the parameter with the effective one Moment, with the deviation, with the correction value of the Clutch torque or with the corrected clutch torque may be due to physical laws or empirical Examinations, especially a priori or before commissioning the motor vehicle, the clutch or the components involved, respectively.

Due to the design of the method according to the invention a simple, under low demands on the Control unit, avoiding regulation and / or iterative adjustment of the clutch torque over several Coupling processes realizable possibility of reduction the deviation of the clutch or starting behavior from one given desired behavior. Furthermore, the Taking into account sudden changes in environmental or Operating parameters possible.

According to a preferred embodiment of the invention, the corrected clutch torque from a functional context determined. The functional context is taken into account at least one parameter. The functional connection can (in addition to a parameter) for example the motor (nominal) moment in Form of a (depending on speed and / or load lever) Consider engine map as well as a change the same in accordance with at least one parameter. The  Dependencies on the parameters can be before the commissioning of the Motor vehicle are determined or at least approximated be and in a simple manner in the control device be implemented.

According to a further proposal of the invention corrected clutch torque with the sum or difference of Coupling torque and one of the at least one parameter dependent correction torque determined. For example by means of the parameter a drop in the drive side to Available indexed and by a adapted reduction of the clutch torque an unchanged or only slightly different coupling behavior or Starting behavior can be achieved.

According to a preferred alternative embodiment of the Invention is the corrected clutch torque with the Multiplication of the clutch torque by one of the determined at least one parameter dependent factor.

The parameter preferably describes an operating state at least one in operative connection with the drive member standing consumer. For example, the Characteristic whether the consumer is switched on or off, in particular is moved with the drive train or not. Furthermore, the parameter can be used with one of the operating parameters correlate the operating torque dependent on the consumer. In particular, the consumer is one Air conditioning compressor, an alternator and / or one Servo pump drive. From the parameter, the Operating torques for actuation and possibly for acceleration the consumer and the resulting reductions of the available torque on the drive side of the Clutch can be determined.

This is a preferred method according to the invention characterized in that a temperature is detected and this as  Characteristic is used. For example, it is an air, intake, fuel, ambient, clutch or Gas exchange medium temperature.

The temperature is then recorded in particular advantageous if a acting on the clutch or necessary moment depends on the temperature. For example, this can be done on the drive side Provided moment from the ambient temperature or a supply temperature of the media supplied to a combustion chamber be pending and determined using the measured parameter become. When detecting the temperature of the engine block can, for example, load peaks during the cold start avoided or loss of performance modeled. Furthermore, a temperature of the clutch can be detected and by correcting the clutch torque temperature-dependent change in the tribological conditions on the coupling.

Furthermore, an existing additional friction torque, For example, the engine due to changes Operating temperatures, a changed bearing friction or the Age of the engine detected by a parameter and / or be modeled.

It is also proposed to record a pressure. This is, for example, the ambient pressure or the pressure in the feed area of the combustion media or the Pressure or operating parameters of an exhaust gas turbocharger or Compressor to a combustion chamber pressure or a Exhaust back pressure. In the case of pressure detection, a change can occur des (still speed and / or load lever dependent) Engine map are modeled.

According to a further proposal according to the invention, a Operating time, operating frequency or operating intensity measured or with the help of suitable organs and / or  saved. For example, the captured Size based on engine life. As a result, empirically determined, depending on the operating time of the engine Engine maps can change the engine torque, for example as a result of wear and tear during the determination of the corrected clutch torque are taken into account. Alternatively or additionally, the operating time Frequency or intensity of operation of the clutch as a parameter can be recorded. As a result, for example, empirically determined dependencies modeled by the parameter can a change in clutch behavior, for example due to wear or a change in tribological conditions when determining the corrected clutch torque are taken into account.

According to a preferred embodiment of the invention a loading condition of the motor vehicle is detected. This Recording can be done, for example, by manual specification, for example by means of a switch operated by the driver, or by a sensor, for example in the area of Shock absorbers. With a change in Load state changes the sluggishly moved by the engine Dimensions. To achieve an unchanged acceleration behaves when there is a change in the loading condition different engine torque and / or a correspondingly required one Coupling torque can be generated according to the parameter. Analogous can adapt to a changed moment of inertia due to changed rotational inertia when changing gears respectively.

Advantageous further developments result from the Subclaims and the description. A preferred one Embodiment of the device according to the invention explained below with reference to the drawing.

Show it:  

Fig. 1 is a block diagram of an embodiment according to the invention,

Fig. 2 shows an engine map with the engine torque as a function of engine speed and load lever position,

Fig. 3 shows an engine map corresponding to FIG. 2 in the starting or clutch area with clutch torques (curves) and

Fig. 4 shows a curve of the engine speed over the clutch duration.

In a motor vehicle 10 , a drive train has a drive element 11 , in particular a motor or an internal combustion engine, and an output element 12 . For the transmission of a rotary movement and a drive torque, the drive element 11 and the output element can be released from one another via a coupling 13 and can be brought into operative connection in accordance with an actuator 14 .

The clutch 13 has a drive side connected to the drive element 11 and an output side connected to the output element 12 . The drive and driven side are mutually movable transversely to their plane of rotation. The movement, the generation of a normal force between the drive side and the output side and / or the generation of a frictional torque between them takes place in accordance with the setting element 14 .

The actuating member 14 is controlled via a control device 15 . The control device 15 is supplied with input signals, in particular parameters.

The parameters can be driver signals 16 , for example a driver's request, for example after a certain (starting) acceleration, or a loading state transmitted by the driver.

A characteristic variable can be an ambient signal 17 , for example an ambient pressure, an ambient temperature or a roadway inclination.

An operating signal 18 of the motor vehicle can be used as a further or alternative parameter, for example the speed of the engine or an engaged gear stage such as the forward or reverse gear.

A possible parameter is an operating signal 19 of the drive element 11 . This can be, for example, a signal taken from the engine control.

Alternatively or additionally, a clutch signal 20 and / or an actuator signal 21 , in particular a temperature or a load state of the clutch 13 or the actuator 14 , can be used as a parameter.

It is also possible to use a signal 44 of the output member as a parameter.

Consumers 22 , 23 can be switched on in accordance with operating or environmental parameters or the driver's requirements or can be operated in different operating states. The consumers 22 , 23 can be coupled into the power flow between the drive member 11 and the drive member 12 via separate clutches, not shown in FIG. 1, preferably with predefined or variable speed ratios relative to the drive member 11 or drive member 12 . The torque provided by the engine is divided between the torque acting on the clutch 13 on the drive side and possibly the torque required to operate the consumer 22 . The torque available on the output side of the clutch 13 is divided into the torque for operating the output member 12 and, if applicable, the torque required for operating the consumer 23 . A consumer signal 24 from consumer 22 and / or a consumer signal 25 from consumer 23 can be used in control device 15 as a further parameter.

FIG. 2 shows a possible exemplary embodiment of an engine characteristic diagram, in which a dependency 26 , 27 of an engine torque 28 on a rotational speed 29 of the engine is shown for an operating parameter, in particular for a load lever position 30 or a throttle valve angle. For example, a dependency 26 , 27 corresponds to a torque dependency for a load lever position specified by the driver during the starting process.

FIG. 3 shows a partial area of a dependency 26 , 27 of FIG. 2 on an enlarged scale, in particular in the area between an idling speed 30 at the time of the start of the clutch or starting process and a synchronous speed 31 at the time of the end of the clutch or starting process . According to operating or environmental parameters, in particular temperature or pressure differences, for example of the intake media or the engine block, and / or an operating time, frequency and intensity, the dependency 26 , 27 can be reduced to a reduced dependency 34 , 35 , in particular a reduced engine torque. The difference between the dependency 26 , 27 and the reduced dependency 34 , 35 is a deviation 36 , 37 , which results in particular from a (also speed-dependent) loss torque. The deviation 36 , 37 can be any function of the speed and can be determined, for example, empirically or from physical laws.

The engine torque of the engine is transmitted via suitable transmission means to the drive side of the clutch 13 . The dependencies 34 , 35 can also describe or approximate the torque available on the drive side of the clutch 13 . In this case, the deviations 36 , 37 result, for example, from at least one additional consumer 22 , 23 driven by the motor, which reduces the available torque. The consumer is, for example, an air conditioning compressor, an alternator or a servo pump drive.

Furthermore, the dependency 34 , 35 can at least approximate the drive torque required or available for accelerating the motor vehicle on the drive side. In this case, the deviations 36 , 37 include, in particular, driving resistance on the transmission side, a road condition such as a road gradient, a loading condition, or the wind conditions.

A clutch torque 38 represents the course of a speed-dependent clutch torque during a start-up or clutch operation, for example the clutch torque 38 before the start of the clutch or start-up operation (at the idle speed 30 ) is approximately zero or minimal and is maximum when the synchronous speed 31 is reached and approximately the synchronous speed of the dependence 26, 31 corresponds to the corresponding value of the engine torque according to the 27th The synchronous speed corresponds, for example, to the speed for reaching a minimum slip (for the first time, approximately).

Between the idling speed 30 and the synchronous speed 31 , the dependence of the clutch torque, for example on the speed 29 , is arbitrarily dependent on at least the speed 29 , in particular according to a functional relationship, according to a curve or a polygon.

The generation of the control device 15 predetermined or learned clutch torque 38 occurs by means of suitable agents of the controller 15 to the actuator fourteenth

If, as a result of the deviations 36 , 37, there is a reduced dependency 34 , 35 in a clutch or starting operation with the clutch torque 38 , a predetermined synchronization point 39 with the synchronization speed 31 and a synchronization torque shifts to the changed synchronization point 40 , in particular with a lower engine speed and a smaller moment available. If, for example, the synchronization point 39 is arranged in a maximum of the dependency 26 , 27 , the changed synchronization point can be shifted from the maximum of the dependency 34 , 35 .

By means of a corrected clutch torque 41 , an undesired shift can be counteracted, so that an adapted synchronization point 42 results, at which in particular the synchronous speed 31 is present.

The corrected clutch torque 41 (or a corresponding control signal of the actuator 14 ) results in the control device 15 according to a functional relationship f (speed; deviations 36 , 37 ; detected parameters 16 to 21 , 24 , 25 , 44 ;...). For example, the clutch torque 41 results from the difference between the clutch torque 38 and a correction torque 43 proportional to a parameter or the deviation 36 , 37 or from the multiplication of the clutch torque 38 by a factor dependent on a parameter or the deviation 36 , 37 .

The course of the speed 29 of the drive element 11 and the transmission input speed 45 over the time 46 is shown in FIG. 4 for a starting process from rest or at low driving speeds. At the start of the starting process 47 , the wheel or transmission input speed 45 is (approximately) zero. The speed 29 corresponds approximately to an idle speed 48 . The speed 29 is changed , for example an increase in the speed 29 to a starting speed 49 at the time 50, by a suitable control of the drive element 11 or the clutch 13 with assigned structural units. By suitably controlling the clutch 13 and / or the drive member 11 , the speed 29 is further influenced, for example in accordance with the profile shown in FIG. 4. As a result of the clutch torques transmitted by the clutch 13 , the transmission input speed 45 increases , for example linearly. At a synchronization point 39 , 40 , 42 , the speed 29 of the drive member 11 corresponds to the transmission input speed 45 . The course of the speed 29 and the transmission input speed 45 is arbitrary, the starting point at the time of the start of the starting process 47 being predetermined for the speed 29 by the idling speed and approximately equal to zero for the transmission input speed 45 and speeds 29 , 45 at the synchronization point 39 , 40 , 42 correspond.

While the speed 29 increases from the start of the starting process until the starting speed 49 is reached , the clutch 13 can be fully opened, partially engaged or progressively engaged. If the clutch 13 is fully opened during this process, the zero point of the course of the transmission input speed 45 shifts in time, for example to the time when the starting speed 49 is reached .

The method according to the invention is particularly suitable for a control of the clutch torque. Alternatively, it can Method according to the invention also in the context of a regulation are used, in addition to the regulation by means of Characteristic an estimate of time variant (operational or Environmental) parameters.

Claims (19)

1. A method for controlling the transmission of a torque from a drive member ( 11 ) to an output member ( 12 ) in connection with the drive of motor vehicles ( 10 ) with

• a) an automated clutch ( 13 ), by means of which a clutch torque ( 38 ) is transferred from a drive side of the clutch ( 13 ) assigned to the drive member ( 11 ) to an output side ( 12 ) assigned to the output side of the clutch ( 13 ) or in the reverse direction ,
• b) an actuating element ( 14 ), by means of which the clutch torque ( 38 ) is generated,
• c) a control device ( 15 ) acting on the actuator ( 14 ), to which signals are fed and by means of which different clutch torques ( 38 ) are generated as a function of the signals,

characterized in that

• a) at least one parameter ( 16-21 , 24 , 25 , 44 ) is detected, which is a deviation ( 36 , 37 ) of an effect on the coupling ( 13 ) that is desired, desired or available as a function of operating and / or environmental parameters Describes a moment ( 34 , 35 ) from a predetermined moment ( 26 , 27 ) that indicates or approximates the deviation ( 36 , 37 ),
• b) and that a corrected clutch torque ( 41 ) is determined by means of the at least one parameter ( 16-21 , 24 , 25 , 44 ) and
• c) the clutch ( 13 ) is actuated to at least approximate the determined corrected clutch torque ( 41 ).

2. The method according to claim 1, characterized in that a parameter describes the deviation of a torque available on the drive side of the clutch ( 13 ) from a predetermined torque, the deviation indexed or approximated. 3. The method according to claim 2, characterized in that a parameter ( 19 ) describes the deviation of a torque made available by the engine from a torque determined under defined conditions, indexes or approximates the deviation 4. The method according to claim 2, characterized in that a parameter ( 24 , 25 ) describes an operating state of at least one with the drive member ( 11 ) operatively connected consumer ( 22 , 23 ). 5. The method according to claim 4, characterized in that it is at least partially an air conditioning compressor in the consumer ( 22 ; 23 ). 6. The method according to claim 4, characterized in that the consumer ( 22 ; 23 ) is at least partially an alternator. 7. The method according to claim 4, characterized in that the consumer ( 22 ; 23 ) is at least partially a servo pump drive. 8. The method according to any one of the preceding claims, characterized in that a parameter ( 19 ) describes at least partially an additional friction torque of the drive member. 9. The method according to any one of the preceding claims, characterized, that a pressure is recorded and this as a parameter is used. 10. The method according to claim 1, characterized, that a parameter is the deviation of one on the output side the clutch necessary torque from a predetermined Moment describes, the deviation is indicated or approximated. 11. The method according to claim 10, characterized in that a load state of the motor vehicle ( 10 ) is detected and this is used as a parameter. 12. The method according to any one of the preceding claims, characterized, that the parameter is used to control the start-up process becomes. 13. The method according to any one of the preceding claims, characterized in that the corrected clutch torque ( 41 ) is determined from a functional relationship, the functional relationship taking into account at least one parameter. 14. The method according to claim 13, characterized in that the corrected clutch torque ( 41 ) with the sum or difference of the clutch torque ( 38 ) and a correction torque ( 43 ) dependent on at least one parameter is determined. 15. The method according to claim 13, characterized in that the corrected clutch torque ( 41 ) is determined by multiplying the clutch torque ( 38 ) by a factor dependent on the at least one parameter. 16. The method according to any one of the preceding claims, characterized, that a temperature is recorded and this as a parameter is used. 17. The method according to claim 16, characterized, that the coupling temperature is calculated or measured and is used as a parameter. 18. The method according to any one of the preceding claims, characterized, that an operating period, operating frequency or Operating intensity is recorded and this as a parameter is used. 19. The method according to any one of the preceding claims, characterized, that a rate of change of the load lever during the Starting process is used as a parameter.