JP6412324B2 - Cruise control equipment - Google Patents

Description

  The present invention reduces the uncomfortable feeling given to the driver by suppressing the increase of the input shaft rotation speed of the automatic transmission even when the traveling resistance increases due to traveling on an uphill road while traveling under cruise control. The present invention relates to a cruise control device.

  Generally, in this type of cruise control device, the target torque of the engine and the target rotation of the input shaft of the automatic transmission are determined according to the difference (speed difference) between the vehicle speed set by the driver (set vehicle speed) and the speed of the host vehicle. By controlling the engine output and the gear ratio of the automatic transmission, the vehicle speed (vehicle speed) is controlled to converge to the target vehicle speed set based on the set vehicle speed. .

  In addition, when the vehicle is running under cruise control, when it reaches a road surface with a large traveling load such as an uphill road and the vehicle speed decreases, the cruise control device uses the throttle valve opening in engine control so that the host vehicle speed can immediately reach the target vehicle speed. Is increased to increase the engine output, while in the shift control, the gear ratio is downshifted to increase the torque, thereby accelerating the vehicle to prevent the vehicle speed from dropping.

  In this case, in a vehicle equipped with an engine with a relatively large displacement (hereinafter referred to as a “high displacement vehicle”), even if the running resistance increases, the throttle valve opening is opened to increase the engine torque. The vehicle speed can be converged relatively easily to the target vehicle speed without greatly shifting down the gear ratio of the automatic transmission.

  On the other hand, when a vehicle equipped with a low displacement engine (hereinafter referred to as a “low displacement vehicle”) tries to obtain acceleration equivalent to that of a vehicle equipped with a high displacement engine on an uphill road, It is necessary to increase the engine speed and downshift the gear ratio. However, such a rapid acceleration increases vibration and noise and deteriorates the ride comfort, so many drivers feel uncomfortable.

  As a countermeasure, for example, as disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2010-209983), when the running resistance exceeds a predetermined threshold, an increase in engine speed is suppressed, and an automatic transmission is achieved. If the downshift amount of the gear ratio is suppressed, it is possible to prevent the driver from feeling uncomfortable.

JP 2010-209983 A

  By the way, the cruise control device has a certain time constant so that its own vehicle speed follows the target vehicle speed, thereby removing noise taken from the vehicle speed sensor or the like due to vehicle vibration or the like during traveling, and obtaining smooth controllability. To be able to. Therefore, as disclosed in the above-mentioned document, when the running resistance exceeds a predetermined threshold value, if the increase in the engine speed is uniformly suppressed, the vehicle speed does not increase, and conversely, there is a feeling of insufficient acceleration. Inconvenience to the driver.

  In view of the above circumstances, the present invention does not cause discomfort to the driver due to a sudden increase in the number of rotations of the input shaft of the automatic transmission even when the traveling resistance increases during traveling by cruise control. In addition, an object of the present invention is to provide a cruise control device that can obtain a good ride comfort without giving the driver a feeling of insufficient acceleration.

The present invention provides a target vehicle speed calculation means for setting a target vehicle speed based on a relative speed or a set vehicle speed between the speed of the preceding vehicle and the speed of the host vehicle, and the host vehicle based on the target vehicle speed and the speed of the host vehicle. Target acceleration calculating means for setting a target acceleration for converging the speed of the vehicle to the target vehicle speed, target torque calculating means for setting a target torque for controlling engine control means based on the target acceleration , the target acceleration and the host vehicle Target horsepower calculating means for setting the target horsepower based on the vehicle speed of the vehicle, and target speed calculation for setting the target rotational speed for controlling the rotational speed of the input shaft of the automatic transmission based on the target torque and the target horsepower A cruise control apparatus comprising gain calculating means for setting a gain for limiting the target acceleration, wherein the gain calculating means The gain calculation target horsepower calculating means for setting the target horsepower for gain calculation based on the speed of the host vehicle, and the target horsepower for gain calculation and the speed of the host vehicle are set along an equal vehicle speed line. A target rotational speed calculation unit for gain calculation that sets a target rotational speed for gain calculation based on a target rotational speed map for gain calculation, and a rotational speed gain that is applied to the target acceleration is set based on the target rotational speed for gain calculation. Rotational speed gain calculating means.

According to the present invention, the gain calculation target horsepower set based on the target vehicle speed and the speed of the own vehicle and the speed of the own vehicle are referred to the gain calculation target rotational speed map set based on the equal vehicle speed line. Then, the target rotational speed for gain calculation is set, the rotational speed gain is set based on the target rotational speed for gain calculation, and this rotational speed gain is applied to the target acceleration set when traveling by cruise control. As a result, even when the running resistance increases during running by cruise control, the engine speed set based on the target acceleration does not increase rapidly, and the driver does not feel uncomfortable. Further, since the target acceleration is only by applying a gain speed without target rotational speed of the automatic transmission input shaft is suppressed uniformly, therefore, without giving an insufficient acceleration feeling to the driver , You can get a good ride.

Schematic configuration diagram of vehicle drive system controlled by cruise control device Functional block diagram showing the configuration of the cruise control unit (Part 1) Functional block diagram showing the configuration of the cruise control unit (part 2) Conceptual diagram of target speed map Conceptual diagram of target rotation speed map for gain calculation Conceptual diagram of rotation speed gain table The vehicle behavior by cruise control when the running resistance increases is shown, (a) is a time chart showing the change of the vehicle speed, (b) is a time chart showing the change of the automatic transmission input shaft rotation speed, and (c) is the vehicle. Time chart showing the state of running uphill

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Reference numeral 1 in FIG. 1 denotes an engine mounted on the host vehicle. On the output side of the engine 1, an automatic transmission 4 including a torque converter 2 and a continuously variable transmission (CVT) 3 as an example of an automatic transmission is provided. It is connected continuously.

  The output from the engine 1 is transmitted to the CVT 3 via the fluid of the torque converter 2 or the lock-up clutch 2a provided in the torque converter 2, and after being shifted to a predetermined gear ratio by the CVT 3, this drive is performed. The force is transmitted from the output shaft 5 to the drive wheels such as the rear wheels or the front wheels.

   A throttle valve 7 is interposed in the middle of an intake passage 6 communicating with an intake port (not shown) of the engine 1. The throttle valve 7 is connected to a throttle motor 8 such as a stepping motor, and the throttle motor 8 is driven by a drive signal from an engine control unit 23 described later to control the valve opening.

   A control valve unit 3a is also provided in the CVT 3. The control valve unit 3a shifts a transmission mechanism built in the CVT 3 and applies it to the primary pulley and the secondary pulley of the CVT 3 in accordance with a shift signal (hydraulic signal) from a CVT control unit 24 described later. The hydraulic pressure is adjusted so as to obtain a desired gear ratio. Various types of transmission mechanisms such as a belt type, a chain type, and a toroidal type are known as the transmission mechanism of the CVT 3, but in this embodiment, a belt type or a chain type transmission mechanism having a primary pulley and a secondary pulley. Is described as an example.

  Reference numeral 21 denotes an electronic control unit (ECU) that controls the running state of the vehicle, and is mainly composed of a microcomputer including a well-known CPU, ROM, RAM, and the like. The ECU 21 includes a function for controlling the running state during cruise control (hereinafter abbreviated as “crude control”), an auto cruise control unit 22 as cruise control means, an engine control part 23 as engine control means, and a shift control means. CVT control unit 24 is provided.

  The auto cruise control unit 22 is connected to a cruise control operation switch 26, a preceding vehicle information detection unit 27, a vehicle speed detection unit 28, and a CVT gear ratio detection unit 29. The cruise control operation switch 26 is disposed in the vicinity of the steering handle and includes a cruise control ON / OFF switch and a vehicle speed setting switch. The preceding vehicle information detection unit 27 detects the relative speed Vm between the speed of the preceding vehicle and the speed of the own vehicle (own vehicle speed) V and the inter-vehicle distance Lm as the preceding vehicle information. That is, the preceding vehicle information detection unit 27 has a front recognition device such as a stereo camera, a monocular camera, or a millimeter wave radar or an infrared laser radar, and based on the information ahead of the host vehicle obtained from the front recognition device, A preceding vehicle traveling immediately before the host vehicle is recognized, an inter-vehicle distance Lm between the preceding vehicle and the host vehicle is obtained, and a relative speed Vm with respect to the host vehicle is obtained from a temporal change in the inter-vehicle distance Lm.

  Further, the vehicle speed detection unit 28 detects the host vehicle speed V from the average value of the wheel speeds detected by the wheel speed sensors provided on the front, rear, left and right wheels, respectively. The vehicle speed V may be detected by a known vehicle speed sensor.

  Further, the CVT gear ratio detection unit 29 includes a primary rotational speed sensor and a secondary rotational speed sensor that are disposed on a primary shaft that pivotally supports a primary pulley and a secondary shaft that pivotally supports a secondary pulley provided in the CVT 3. The transmission ratio ε (= Ns / Np) of the CVT 3 is calculated from the ratio between the detected rotation speed of the primary shaft (hereinafter referred to as “primary rotation speed”) Np and the rotation speed Ns of the secondary shaft.

  The auto cruise control unit 22 obtains the target torque TTq of the engine and the target rotational speed TNp of the primary shaft that is the input shaft of the CVT 3 based on these input parameters.

  The engine control unit 23 sets a target throttle opening Tθα based on the target torque TTq obtained by the auto cruise control unit 22, and drives the throttle motor 8 based on the target throttle opening Tθα so that the opening of the throttle valve 7 is increased. Feedback control is performed so as to converge to the target throttle opening Tθα. On the other hand, the CVT control unit 24 variably sets the winding diameter of the primary pulley and the secondary pulley in inverse proportion to control the gear ratio ε, and the primary rotation speed is obtained from the target rotation speed TNp obtained by the auto cruise control section 22. Feedback control is performed as follows.

  2 and 3 show the functional configuration of the auto cruise control unit 22 for obtaining the target torque TTq and the target rotational speed TNp based on the parameters described above. The auto cruise control unit 22 includes a target control value calculation unit 22A shown in FIG. 2 and a gain calculation unit 22B as gain calculation means shown in FIG.

  The target control value calculator 22A is a target vehicle speed calculator 31 as a target vehicle speed calculator, a target acceleration calculator 32 as a target acceleration calculator, an actual acceleration calculator 33, a target driving force calculator 34, and a target torque calculator. The target torque calculation unit 35, the target torque filter processing unit 36, the target horsepower calculation unit 37, the target rotation number calculation unit 38 as the target rotation number calculation means, and the target rotation number filter processing unit 39. The target torque filter processing unit 36 and the target rotational speed filter processing unit 39 correspond to the first filter processing means of the present invention.

  On the other hand, the gain calculation unit 22B sets a gain GN for limiting the target acceleration Ta set by the target acceleration calculation unit 32. The gain calculation target vehicle speed calculation unit 41, the gain calculation target acceleration calculation unit 42, Target driving force calculation unit 43 for gain calculation, target horsepower calculation unit 44 for gain calculation as target horsepower calculation unit for gain calculation, target rotation number calculation unit 45 for gain calculation as target rotation number calculation unit for gain calculation, gain calculation Target rotation speed filter processing section 46 and a rotation speed gain calculation section 47 as rotation speed gain calculation means. The gain calculation target rotational speed filter processing unit 46 corresponds to the second filter processing means of the present invention.

  Next, calculation processing executed by the target control value calculation unit 22A and the gain calculation unit 22B constituting the auto cruise control unit 22 will be described.

  When the driver is driving the host vehicle, if the cruise control switch 26 disposed near the steering handle is turned on, the traveling state of the host vehicle is set to the auto-cruise mode, and the target vehicle speed of the target control value calculation unit 22A is set. The calculation unit 31 reads the set vehicle speed Vs set in advance or the set vehicle speed Vs newly set, and sets this as the target vehicle speed Tv. At that time, the preceding vehicle information of the preceding vehicle information detection unit 27 is read, and when the preceding vehicle is supplemented, the relative speed Vm and the inter-vehicle distance Lm with respect to the preceding vehicle are read, and the speed of the preceding vehicle is determined by the own vehicle speed V. If the vehicle speed is slower, the set vehicle speed Vs is maintained until the inter-vehicle distance Lm reaches a preset target inter-vehicle distance, and when the target inter-vehicle distance is reached, a target vehicle speed Tv at which the relative speed Vm becomes 0 is set.

  The target acceleration calculation unit 32 sets a target acceleration Ta for converging the host vehicle speed V to the target vehicle speed Tv, reads the target vehicle speed Tv, the host vehicle speed V, and a rotation speed gain GN described later, and sets the target acceleration Ta and The speed difference ΔV with respect to the host vehicle speed V is time-differentiated, and the target acceleration Ta is obtained by multiplying the value by the rotational speed gain GN. In addition, the actual acceleration calculation unit 33 calculates the actual acceleration a from the time derivative of the host vehicle speed V. Note that the rotation speed gain GN read by the target acceleration calculation section 32 is set by the gain calculation section 22B shown in FIG. 3, but as will be described later, the rotation speed gain GN is 100 [% below a predetermined target rotation speed. Here, G = 100 [%] will be described for convenience, and details of processing executed by the gain calculation unit 22B will be described later.

The target driving force calculation unit 34 obtains a driving force feedforward component F_Ff and a driving force feedback component F_Fb, and adds both components F_Ff and F_Fb to obtain a target driving force TF. That is, the driving force feedforward component F_Ff is based on the target acceleration Ta and the vehicle weight.
F_Ff = Ta / vehicle weight + running resistance (1)
Ask from. This vehicle weight is a preset fixed value unique to the vehicle. The running resistance is the sum of air resistance, rolling resistance, gradient resistance, and acceleration resistance, and the air resistance and rolling resistance can be obtained in advance based on vehicle specifications, simulation, and the like. Also, the gradient resistance is
Gradient resistance = vehicle weight / sin θ (2)
Can be obtained from Note that θ is a road surface gradient, and is set based on an output device such as an inclination sensor or a longitudinal G sensor.

The acceleration resistance is based on the actual acceleration a,
Acceleration resistance = (a / g) · (vehicle weight + Δw) (3)
Can be obtained from Here, g is a gravitational acceleration, and Δw is an equivalent inertia weight of the rotating portion of the drive mechanism. Therefore, when the gravitational acceleration, the vehicle weight, and the equivalent inertia weight are fixed values, the acceleration resistance can be obtained based on the actual acceleration a.

  On the other hand, the driving force feedback component F_Fb is obtained by the PID control or the like from the difference between the target acceleration Ta and the actual acceleration a, thereby setting the driving force feedback component F_Fb so that the actual acceleration a converges to the target acceleration Ta.

  Then, the two components F_Ff and F_Fb are added to obtain the target driving force TF. This target driving force TF is read by the target torque calculator 35 and the target horsepower calculator 37.

  The target torque calculator 35 reads the target driving force TF and the CVT gear ratio ε, and calculates the target torque TTq from the following equation.

TTq = TF · rd / (ε · i · ηt) (4)
Here, rd is the tire effective radius of the drive wheel, i is the final reduction ratio, and ηt is the power transmission efficiency. Therefore, if these are considered as fixed values, the target torque TTq can be obtained by dividing the target driving force TF by the shift ε.

This target torque TTq is filtered by the target torque filter processing unit 36 using the transfer function of the first time constant Ti,
TTq ← TTq / (1 + Ti · s) (5)
It is output to the engine control unit 23. This first time constant Ti is set in order to remove noise taken in from various sensors due to vehicle vibrations and the like accompanying traveling and to obtain smooth controllability, and is set to a relatively slow response characteristic. ing. Note that s is a Laplace operator.

  Then, the engine control unit 23 sets the opening degree of the throttle valve 7 with reference to an arithmetic expression or a map based on the input target torque TTq and the engine speed detected by an engine speed sensor (not shown). The drive signal to be output is output to the throttle motor 8, and the throttle valve 7 is opened predetermined.

  On the other hand, the target horsepower calculator 37 multiplies the target driving force TF by the host vehicle speed V to obtain the target horsepower TPs (TPs = TF · V). The target horsepower TPs is read by the target rotational speed calculation unit 38.

  The target rotational speed calculation unit 38 sets the target rotational speed TNp for setting the primary rotational speed of the CVT 3 based on the target torque TTq and the target horsepower TPs obtained by the target torque calculation unit 35, and the target rotational speed map shown in FIG. Refer to and set. Since the engine speed and the primary speed are substantially the same during lockup, the target speed TNp is substantially the same as the target speed of the engine.

The horsepower is
Since horsepower = revolution speed / torque, the relationship between the target torque TTq and the target rotation speed TNp is set for each target horsepower TPs in the target rotation speed map shown in FIG. Therefore, the target rotational speed TNp may be obtained from an arithmetic expression.

This target rotational speed TNp is filtered by the target rotational speed filter processing unit 39 by the transfer function of the first time constant Ti,
TNp ← TNp / (1 + Ti · s) (6)
The data is output to the CVT control unit 24.

  Then, the CVT control unit 24 obtains a target gear ratio based on the input target rotational speed TNp and the host vehicle speed V, and downshifts at a predetermined timing so that the current gear ratio reaches the target gear ratio, or Shift control by upshift is performed.

  By the way, in the target control value calculation unit 22A described above, the target acceleration Ta set by the target acceleration calculation unit 32 is set according to the difference between the target vehicle speed Tv and the host vehicle speed V, and the actual acceleration a is set to the target acceleration Ta. In order to achieve this, engine control and CVT shift control are performed with a certain time constant. At that time, in order to make the actual acceleration a reach the target acceleration Ta, the required target driving force TF varies depending on the gradient resistance, the vehicle weight, and the acceleration.

  Therefore, for example, when a low displacement vehicle is traveling in the auto-cruise mode, as shown at time t0 in FIG. 7 (c), when approaching the uphill road, the vehicle speed temporarily increases due to the increase in gradient resistance at the initial stage of uphill. Since the speed difference ΔV between the target vehicle speed Tv and the host vehicle speed V increases, the target acceleration Ta also increases.

  Then, the auto cruise control unit 22 performs control to increase the target torque TTq and the target rotational speed TNp so that the acceleration a reaches the target acceleration Ta with a certain time constant. The engine output of a low displacement vehicle is lower than that of a high displacement vehicle, so when trying to obtain the same driving force as a high displacement vehicle, it is necessary to greatly increase the engine speed and downshift the transmission ratio greatly. There is. As a result, even if the acceleration is satisfied, the engine speed becomes high, which gives the driver an unpleasant feeling.

  In this embodiment, even if the gradient resistance increases, a rotation speed gain GN that suppresses the target acceleration Ta is set in the gain calculation unit 22B in order to suppress an increase in engine speed more than necessary, and the running resistance including the gradient resistance is set. When the engine speed increases, the engine speed is prevented from increasing.

  That is, in the gain calculation unit 22B, first, the gain calculation target vehicle speed calculation unit 41 reads the set vehicle speed Vs and the preceding vehicle information of the preceding vehicle information detection unit 27, and when the preceding vehicle is supplemented, The relative speed Vm and the inter-vehicle distance Lm with respect to the preceding vehicle are obtained. When it is determined that the speed of the preceding vehicle is slower than the own vehicle speed V, the set vehicle speed Vs is maintained until the inter-vehicle distance Lm reaches a preset target inter-vehicle distance, and when the target inter-vehicle distance is reached, the relative speed A target vehicle speed TGv for gain calculation at which Vm becomes 0 is set. On the other hand, when the preceding vehicle is not supplemented, the target vehicle speed TGv for gain calculation is set with the set vehicle speed Vs.

The gain calculation target acceleration calculation unit 42 reads the gain calculation target vehicle speed TGv and the host vehicle speed V, time-differentiates the speed difference ΔV between the gain calculation target acceleration TGa and the host vehicle speed V, and calculates the gain calculation target acceleration TGa. Ask for. The gain calculation target driving force calculation unit 43 calculates the gain calculation target driving force TGF based on the target acceleration Ta, the vehicle weight, and the running resistance.
TGF = TGa / vehicle weight + running resistance (7)
Calculate from The running resistance is as described in the above equation (1).

  The gain calculating target driving force TGF is read by the gain calculating target horsepower calculating unit 44. The gain calculation target horsepower calculation unit 44 multiplies the gain calculation target driving force TGF by the vehicle speed V to obtain the target horsepower TGPs for gain calculation (TGPs = TGF · V).

The gain calculation target rotation speed calculation unit 45 sets the gain calculation target rotation speed TGNp by referring to the gain calculation target rotation speed map based on the gain calculation target horsepower TGPs and the vehicle speed V. FIG. 5 shows a target rotation speed map for gain calculation. The gain calculation target rotational speed map is set along the equal vehicle speed line, and therefore, the gain calculation target rotational speed TGNp is uniformly obtained from the gain calculating target horsepower TGPs and the own vehicle speed V.

The target rotation speed TGNp for gain calculation is filtered by the target rotation speed filter processing unit 46 for gain calculation using the transfer function of the second time constant Tj,
TGNp ← TGNp / (1 + Tj · s)
It is output to the rotational speed gain calculation unit 47. The second time constant Tj is set to a fast response characteristic close to 0 that removes the minimum noise. Therefore, the target rotational speed TGNp for gain calculation is set based on the parameter detected in substantially real time.

  The rotational speed gain calculation unit 47 sets the rotational speed gain GN by referring to the rotational speed gain map based on the target rotational speed TGNp for gain calculation. FIG. 6 shows a rotation speed gain map. As shown in the figure, the rotational speed gain GN is set to 100% when the target rotational speed TGNp for gain calculation is equal to or lower than the set low rotational speed NLo, and is set to the minimum gain GL above the set high rotational speed NHi. It is continuously changed with a quadratic curve between them. The rotational speed gain GN suppresses the engine rotational speed from being over-rotated when the traveling resistance increases during traveling on an uphill road or the like, and the set low rotational speed NLo sets the rotational speed gain GN to 100 [% ], The upper limit of the rotation speed at which the primary rotation speed (= engine speed at the time of lock-up) does not seem to be over-rotation is obtained in advance through experiments or the like.

  The set high rotational speed NHi is a value set with the minimum value of the rotational speed gain GN set by the target rotation speed TGNp for gain calculation. The primary rotational speed is between the set low rotational speed NLo and the set high rotational speed NHi. A rotational speed gain GN is set based on experiments, simulations, or the like to limit the engine so that it does not appear to overspeed as the engine speed increases (when the engine is locked up).

  The rotation speed gain GN is output to the target acceleration calculation unit 32 of the target control value calculation unit 22A described above. The target acceleration calculation unit 32 obtains the target acceleration Ta by multiplying the acceleration Ta ′ obtained based on the speed difference ΔV between the target acceleration Ta and the host vehicle speed V by the rotation speed gain GN (Ta ← Ta ′ · GN).

  As a result, when the target rotational speed TGNp for gain calculation is higher than the set low rotational speed NLo (TGNp> NLo), the rotational speed gain GN is less than 100 [%], so that the target driving calculated by the target driving force calculation unit 34 Therefore, the target torque TTq obtained by the target torque calculator 35 and the target horsepower TPs obtained by the target horsepower calculator 37 are suppressed. As a result, in the target torque calculation unit 35, an increase in the target rotational speed TNp obtained based on the target torque TTq and the target horsepower TPs is suppressed. Therefore, an increase in primary rotation speed Np controlled by CVT control unit 24 is suppressed, and accordingly, an increase in engine rotation speed is suppressed during lockup.

  As described above, the target torque TTq and the target rotational speed TNp calculated by the target control value calculation unit 22A are filtered by the transfer function of the first time constant Ti having a relatively slow response characteristic in the filter processing units 36 and 39. Therefore, when traveling on a traveling road where traveling resistance increases, such as an uphill road in the auto-cruise mode, the primary rotational speed rises with a slight delay. On the other hand, since the rotation speed gain GN set by the gain calculation unit 22B is filtered by the transfer function of the second time constant Tj having a fast response characteristic, the gain calculation target rotation speed TGNp set almost in real time is used. A corresponding rotation speed gain GN is set.

  On the other hand, the parameters input to the target acceleration calculation unit 32 are almost real time, and are quickly limited by the rotational speed gain GN. Therefore, the target torque TTq output to the engine control unit 23 and the CVT control unit 24 are output. The target rotational speed TNp output to can suppress an increase in the rotational speed of the primary shaft even when traveling resistance increases due to traveling on an uphill road or the like.

  That is, when the target acceleration Ta is not limited by the rotational speed gain GN, the low displacement vehicle running in the auto cruise mode reaches the uphill road, and the vehicle speed V temporarily increases due to the increase in running resistance as shown by the broken line in FIG. When the speed decreases (time t0), the target acceleration Ta is increased to return the vehicle speed V to the set vehicle speed Vs. Therefore, the peak of the primary rotational speed Np is excessively rotated as indicated by Np3 in FIG. The ride feels worse (time t1) and the ride quality deteriorates.

  On the other hand, in the present embodiment, when traveling on an uphill road, an increase in travel resistance is quickly detected, and a gain calculation target rotational speed TGNp is obtained based on the gain calculation target horsepower TGPs and the vehicle speed V at that time. Since the rotation speed gain GN is set based on the target rotation speed TGNp for gain calculation and the target acceleration Ta is limited by this, the increase in acceleration is suppressed as shown by the solid line in FIG. However, the peak of the primary rotational speed Np is suppressed to the extent indicated by Np2 (time t2). As a result, it is possible to obtain a good ride comfort without giving the driver unpleasant feeling in a driving region where traveling resistance increases such as traveling on an uphill road. Further, although the acceleration is suppressed by the rotational speed gain GN, only the inclination of the increase in the vehicle speed V is reduced, and the vehicle is accelerated by an appropriate increase in the rotational speed, which may give the driver a feeling of insufficient acceleration. Absent.

  Note that the present invention is not limited to the above-described embodiment. For example, even in the case of a high displacement vehicle or a vehicle equipped with a turbocharger, when traveling in an economy mode that places importance on fuel efficiency, When the auto cruise mode is executed in the economy mode, the target control value calculation unit 22A may read the rotation speed gain set by the gain calculation unit 22B and limit the target acceleration Ta with the rotation speed gain GN.

1 ... Engine,
3 ... continuously variable transmission,
3a ... Control valve unit,
4 ... Automatic transmission,
7 ... Throttle valve,
8 ... Throttle motor,
21 ... Electronic control unit ,
22 ... Auto cruise control part,
22A ... Target control value calculation unit,
22B ... Gain calculation section,
23. Engine control unit,
24 ... CVT control unit,
26 ... cruise control switch,
27. A preceding vehicle information detection unit,
28 ... Vehicle speed detection unit,
29 ... gear ratio detection unit,
31 ... Target vehicle speed calculation unit,
32 ... Target acceleration calculation part,
33 ... Actual acceleration calculation unit,
34 ... Target driving force calculation unit,
35 ... Target torque calculation section,
36 ... Target torque filter processing unit,
37 ... Target horsepower calculation unit,
38 ... target rotational speed calculation unit,
39: Target rotational speed filter processing unit,
41 ... Target vehicle speed calculation unit for gain calculation,
42 ... Target acceleration calculation unit for gain calculation,
43 ... Target driving force calculation unit for gain calculation,
44 ... Target horsepower calculation unit for gain calculation,
45 ... Target rotational speed calculation unit for gain calculation,
46 ... Target rotational speed filter processing unit for gain calculation,
47. Revolution gain calculation unit,
a ... Actual acceleration,
GN ... Rotational speed gain,
Lm ... inter-vehicle distance,
Ta: Target acceleration,
TF ... Target driving force,
TGa: Target acceleration for gain calculation,
TGF: Target driving force for gain calculation,
TGNp: Target rotational speed for gain calculation,
TGPs: Target horsepower for gain calculation,
TGv: Target vehicle speed for gain calculation,
Ti: first time constant,
Tj ... second time constant,
TNp: Target rotational speed,
TPs… Target horsepower,
TTq ... Target torque,
Tv ... Target vehicle speed,
V ... Vehicle speed,
Vm ... relative speed,
Vs ... set vehicle speed,
ΔV ... speed difference,
ε ... speed ratio

Claims (3)

Target vehicle speed calculation means for setting a target vehicle speed based on the relative speed of the speed of the preceding vehicle and the speed of the host vehicle or the set vehicle speed;
Target acceleration calculating means for setting a target acceleration for converging the speed of the host vehicle to the target vehicle speed based on the target vehicle speed and the speed of the host vehicle;
Target torque calculation means for setting a target torque for controlling the engine control means based on the target acceleration;
Target horsepower calculating means for setting a target horsepower based on the target acceleration and the vehicle speed of the host vehicle;
In a cruise control device comprising: a target rotational speed calculation means for setting a target rotational speed for controlling the rotational speed of the input shaft of the automatic transmission based on the target torque and the target horsepower ;
Gain calculating means for setting a gain for limiting the target acceleration;
The gain calculating means includes
Gain calculation target horsepower calculating means for setting a target horsepower for gain calculation based on the target vehicle speed and the speed of the host vehicle;
A target rotational speed for gain calculation that sets a target rotational speed for gain calculation based on a target rotational speed map for gain calculation that is set along a constant vehicle speed line from the target horsepower for gain calculation and the speed of the host vehicle Computing means;
A cruise control device comprising: a rotation speed gain calculating means for setting a rotation speed gain to be applied to the target acceleration based on the target rotation speed for gain calculation. First filter processing means for filtering the target torque and the target rotational speed with a transfer function of a first time constant;
2. The cruise control device according to claim 1, further comprising second filter processing means for filtering the rotation speed gain with a transfer function having a second time constant having a response characteristic faster than the first time constant. The cruise control device according to claim 2, wherein the second time constant is set to a value close to zero.

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