JP2001342866A - Driving force control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent delay in acceleration at re-acceleration on a winding road when driving force increasing control to add grade resistance is cancelled in releasing accelerator. SOLUTION: Target driving force Tdo on a flat road and a grade resistance added part (Rf×α) calculated by multiplying the grade resistance Rf and a grade resistance adding rate αare obtained, and target driving force Tdt is obtained by addition of these. The grade resistance adding rate α is made to be small in releasing the accelerator while making α large in other time. A target transmission gear ratio It for generating the target driving force Tdt under a current vehicular speed VSP with a minimum rate of fuel consumption is obtained, and a target engine power torque Tet is obtained by dividing the target driving force Tdt by an actual transmission gear ratio I of a transmission 2 to obtain a required throttle opening TVOo of Tet. TVOo and a throttle opening value 0 corresponding to accelerator release is inputted, and engine power is controlled with setting a target throttle opening TVOt to 0 when FLAG is 0. The FLAG is made to be 0 in releasing the accelerator, while the FLAG is made to be 0 after a lapse of set time of a timer TM on the winding road.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is equipped with an engine capable of arbitrarily changing the output torque by a factor other than the operation of the accelerator pedal and a power train which is combined with an automatic transmission. ,
The present invention relates to a driving force control device for a vehicle that controls a target driving force determined according to driving conditions to be achieved.

[0002]

2. Description of the Related Art Conventionally, as this kind of driving force control device,
For example, the applicant of the present application has proposed the one described in JP-A-2000-27985. This driving force control device is a combination of an engine that can arbitrarily change the output torque by a factor other than the amount of depression of the accelerator pedal operated to instruct the engine output required by the driver, and a continuously variable transmission. In the power train, the target driving force is determined from the accelerator pedal depression amount and the vehicle speed, and the combination of the throttle opening of the engine and the gear ratio of the continuously variable transmission is determined so that the target driving force is achieved, for example, with optimum fuel efficiency. It will be realized.

[0003] When calculating the target driving force, the conventional driving force control device adds a gradient resistance corresponding to the gradient of the uphill road to the target driving force during traveling on the uphill road. It has also been proposed to perform a driving force increase control that increases so that crisp running is possible.

[0004]

In the conventional driving force control device, the above-described driving force increase control is performed as long as the vehicle is traveling on an uphill road. Therefore, it is attempted to decelerate or stop the vehicle on the uphill road. Even when the depression amount of the accelerator pedal is reduced to zero by releasing the accelerator pedal, the driving force increase control is continued, which not only gives a feeling of discomfort to the traveling feeling, but also leads to a wasteful increase in engine output and a deterioration in fuel efficiency.

In order to solve this problem, it is conceivable to stop the driving force increase control when the depression amount of the accelerator pedal becomes zero by releasing the accelerator pedal. However, in this case, the following problem occurs while the vehicle is traveling uphill on a so-called winding road in which alternately curved roads are alternately reversed.

That is, while the vehicle is running on a winding road, the accelerator pedal is temporarily released for deceleration every time the vehicle reaches a corner of a curved road, but immediately thereafter, the operation of depressing the accelerator pedal again is repeated. However, as described above, the measure to simply stop the driving force increase control when the accelerator pedal is released means that the driving force increase control is also stopped when the accelerator pedal is temporarily released when approaching a corner of a curved road. Therefore, the rise of the engine output when the accelerator pedal is depressed again immediately afterward tends to be delayed, and the driver feels a delay in acceleration after passing through a corner of a curved road.

The first invention according to the first aspect of the present invention follows the above-described measure that the driving force increase control during traveling on an uphill road is stopped when the accelerator pedal is released, but when the uphill road is a winding road, An object of the present invention is to solve the problem of acceleration delay when the accelerator pedal is depressed again after passing through a corner of a curved road by continuing the driving force increase control even when the accelerator pedal is released.

A second object of the present invention is to provide a driving force increase control during traveling on an uphill road which is easily realized only by changing a method of determining a target driving force.

A third object of the present invention is to easily stop the driving force increase control for traveling uphill when the accelerator pedal is released.

According to a fourth aspect of the present invention, when the driving force increase control for traveling on an uphill road is continued even when the accelerator pedal is released due to the winding road, the accelerator pedal is released despite the release of the accelerator pedal. It is an object of the present invention to eliminate the discomfort that the vehicle accelerates and to enable rapid acceleration when the accelerator pedal is depressed again thereafter.

According to a fifth aspect of the present invention, when the driving force increase control for traveling on an uphill road is continued even when the accelerator pedal is released because of the winding road, the continuation does not continue forever. By doing so,
It is an object of the present invention to obtain a required deceleration when a sufficient deceleration is desired or a stop is desired.

[0012]

To achieve these objects, a vehicle driving force control apparatus according to a first aspect of the present invention includes an engine capable of arbitrarily changing an output torque by factors other than the operation of an accelerator pedal, and an automatic transmission. A vehicle equipped with a power train that is a combination of the following and controls at least the output torque of the engine so that the target driving force determined according to the driving conditions is achieved. When the accelerator pedal is released even while traveling on an uphill road, the driving force increase control is stopped. When the uphill road is a winding road, the driving force increase control is performed even when the accelerator pedal is released. Is continued.

According to a second aspect of the present invention, there is provided a driving force control device for a vehicle.
In the first invention, the target driving force is determined while traveling on an uphill road,
The driving force increase control is performed by setting a target driving force to which a gradient resistance determined according to an uphill road gradient is added.

According to a third aspect of the present invention, there is provided a driving force control device for a vehicle.
In the first invention or the second invention, the driving force increase control at the time of releasing the accelerator pedal is stopped only by fully closing the engine throttle opening corresponding to the release of the accelerator pedal. Things.

According to a fourth aspect of the present invention, there is provided a driving force control apparatus for a vehicle.
In any one of the first to third inventions, the driving force when the driving force increase control is continued because the vehicle is traveling on a winding road even when the accelerator pedal is released includes a gradient resistance corresponding to the gradient of the uphill road. The driving resistance is smaller than the running resistance of the vehicle.

A vehicle driving force control device according to a fifth aspect of the present invention
In any one of the first to fourth aspects of the present invention, even when the accelerator pedal is released, the driving time increase control is continued because the vehicle is traveling on a winding road, and the duration is set to be limited. The driving force increase control is stopped after elapse of.

[0017]

The output torque of the engine can be arbitrarily changed by factors other than the operation of the accelerator pedal.
The output from the engine capable of performing such torque control is shifted by an automatic transmission to become the output of a power train. At this time, at least the output torque of the engine is controlled such that the target driving force determined according to the operating conditions is achieved.

According to the first aspect of the present invention, since the driving force increase control for increasing the driving force in accordance with the gradient of the uphill road is performed during the uphill traveling, the driving force does not become insufficient even on the uphill road, and the driving can be performed sharply. . However, in the first invention, the driving force increase control is stopped when the accelerator pedal is released even when the vehicle is running on an uphill road, and therefore, when the accelerator pedal is released to decelerate or stop the vehicle on the uphill road, the driving force increase control is performed. Is not continued, and the above-mentioned problem that the driving feeling becomes uncomfortable or the fuel consumption is deteriorated due to an unnecessary increase in engine output can be solved.

Further, in the first invention, when the uphill road is a winding road, the driving force increase control is continued even when the accelerator pedal is released. To prevent the drive power increase control from being interrupted when the accelerator pedal is temporarily released, and to prevent a delay in the rise of the engine output when the accelerator pedal is depressed immediately thereafter. Can be
The aforementioned problem that the driver feels a delay in acceleration after passing through a corner of a curved road can also be avoided.

In the second aspect of the present invention, the above-described driving force increase control is performed by setting the target driving force during traveling on an uphill road to a target driving force to which a gradient resistance determined according to an uphill road gradient is added. Therefore, the driving force increase control during traveling on an uphill road can be easily realized only by changing the method of determining the target driving force, which is very advantageous.

In the third aspect of the present invention, the driving force increase control when the accelerator pedal is released is stopped only by fully closing the engine throttle opening in response to the release of the accelerator pedal. It is very advantageous that the road running drive force increase control can be easily stopped.

According to the fourth aspect of the present invention, a vehicle in which the driving force when the above-described driving force increase control is continued because the vehicle is running on a winding road even when the accelerator pedal is released includes a gradient resistance corresponding to the gradient of the uphill road. When the driving force increase control for traveling on an uphill road is continued even when the accelerator pedal is released due to the winding road, the vehicle accelerates despite the release of the accelerator pedal. It is possible to eliminate the feeling of discomfort, and to enable rapid acceleration when the accelerator pedal is depressed again thereafter.

In the fifth aspect, even when the accelerator pedal is released, the duration of the driving force increase control is limited because the vehicle is traveling on a winding road, and the set time has elapsed since the release of the accelerator pedal. After that, the driving force increase control is stopped, so that even if the accelerator pedal is released due to the winding road, the driving force increase control for traveling on the ascending road does not continue forever. In such a case, it is possible to obtain the required deceleration when a sufficient deceleration is desired or when a stop is desired.

[0024]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a power train of a vehicle including a driving force control device according to an embodiment of the present invention, and a control system thereof.
And a continuously variable transmission 2 as an automatic transmission. Although the engine 1 is a gasoline engine, the engine 1 is not mechanically connected to an accelerator pedal 3 operated by a driver, but is separated from the accelerator pedal 3 and includes a throttle valve 5 whose opening is electronically controlled by a motor 4. By setting 4 to a rotational position corresponding to a target throttle opening (TVot) command, the throttle valve 5 is set to the target throttle opening TVot, so that the output of the engine 1 can be controlled by factors other than the accelerator pedal operation. And

The continuously variable transmission 2 is a well-known V-belt type continuously variable transmission, and includes a primary pulley 7 drivingly connected to an output shaft of the engine 1 via a torque converter 6 and a secondary pulley 8 aligned with the primary pulley 7. And a V-belt 9 stretched between these pulleys. Then, a differential gear device 11 is drive-coupled to the secondary pulley 8 via a final drive gear set 10, and the wheels (not shown) are rotationally driven by these.

To change the speed of the continuously variable transmission 2, one of the flanges forming the V-grooves of the primary pulley 7 and the secondary pulley 8 is relatively moved closer to the other fixed flange. The width of the V-groove can be reduced or the width of the V-groove can be widened by separating the two movable flanges from the primary pulley pressure Ppri and the secondary pulley pressure Psec from the hydraulic actuator 12 responsive to the target speed ratio (It) command. By displacing the continuously variable transmission 2 to a corresponding position, the continuously variable transmission 2 can be continuously variable shifted so that the actual gear ratio matches the target gear ratio It.

The target throttle opening TVot and the target speed ratio It are calculated and obtained by the controller 13, respectively. Because of this, the controller 13
A signal from an accelerator pedal operation amount sensor 14 for detecting the depression position (accelerator pedal depression amount) APS of the accelerator pedal 3, a signal from a crank angle sensor 15 for detecting the engine speed Ne, and a throttle opening TVO
From the throttle opening sensor 16 for detecting the rotation speed and the transmission input rotation speed Ni that is the rotation speed of the primary pulley 7.
From the transmission input rotation sensor 17 for detecting the rotation speed and the transmission output rotation speed No, which is the rotation speed of the secondary pulley 8.
, A signal from a vehicle speed sensor 19 for detecting a vehicle speed VSP, and road information from a navigation system 20.

Based on the input information, the controller 13 controls the speed change of the continuously variable transmission 2 and the throttle opening (output) of the engine 1 in the following manner, as shown in the functional block diagram of FIG. Thus, the driving force control of the vehicle targeted by the present invention is executed. The flat road target driving force calculation unit 31 calculates the accelerator pedal depression amount APS detected by the sensor 14 and the vehicle speed V detected by the sensor 19.
Based on the SP, for example, a required minimum flat road target driving force Tdo during flat road traveling is obtained by a method described in Japanese Patent Application Laid-Open No. 7-172217 or from a scheduled map illustrated in FIG.

The gradient resistance calculating section 32 calculates the gradient resistance on the basis of the information on the gradient of the uphill road from the navigation system 20 according to the method described in JP-A-2000-27985.
A gradient resistance Rf acting on the vehicle is determined. The multiplier 33 multiplies the gradient resistance Rf by a gradient resistance addition rate α, which will be described in detail later, to obtain a gradient resistance addition (Rf × α), and the adder 34 adds the gradient resistance Rd to the flat road target driving force Tdo. Addition (Rf
× α) is added to determine the target driving force Tdt.

In the target gear ratio calculating section 35, the target driving force T
From the dt and the vehicle speed VSP, for example, a target gear ratio It for generating the target driving force Tdt at the lowest fuel consumption under the current vehicle speed VSP is searched based on, for example, a map illustrated in FIG. When the target gear ratio It is obtained by the target gear ratio calculator 35, the target driving force Tdt is replaced with the above-described search.
From the vehicle speed VSP, for example, a target transmission input rotation speed Nit for generating the target driving force Tdt at the lowest fuel consumption under the current vehicle speed VSP is searched by a map, and the target transmission input rotation speed Nit and the sensor 18 detect the target transmission input rotation speed Nit. Using the obtained transmission output rotational speed No, the target speed ratio It is calculated as It = Nit /
It can also be calculated by calculating No.

The target speed ratio It is determined by the stepless transmission 2 shown in FIG.
The transmission control is performed such that the continuously variable transmission has the target speed ratio It, in other words, the transmission input rotation speed has the target value Nit.

The target engine output torque calculating section 36 calculates the target driving force Tdt with the actual speed ratio I (= Ni / No) represented by the ratio of the input speed Ni to the output speed No of the continuously variable transmission 2. By dividing, a target engine output torque Tet required to obtain the target driving force Tdt is obtained. Since the torque converter 6 exists between the engine 1 and the continuously variable transmission 2, in order to obtain the target engine output torque Tet more accurately, the sensor 15,
The speed ratio e of the torque converter 6 is calculated by e = Ni / Ne from the engine speed Ne (input speed of the torque converter 6) and the transmission input speed Ni (output speed of the torque converter 6) detected at 17. The torque ratio t of the torque converter 6 is searched from the speed ratio e based on a map corresponding to the performance diagram of the torque converter 6, and the target driving force Tdt is sequentially divided by the actual speed ratio I and the torque ratio t to obtain the target torque. Needless to say, it is necessary to obtain the engine output torque Tet.

The required throttle opening calculating section 37 calculates the target engine output torque T from the target engine output torque Tet and the engine speed Ne detected by the sensor 15.
The required throttle opening TVOo for generating et is obtained, and this is commanded to the target throttle opening selector 38. The target throttle opening selection section 38 receives the required throttle opening TVOo and the throttle opening value 0 corresponding to the release of the accelerator pedal, and inputs the former required throttle opening when the flag FLAG described later is 1. TVO
o is output as the target throttle opening TVot, and when the flag FLAG is 0, the latter throttle opening value 0 is output as the target throttle opening TVot.

The target throttle opening TVot determined in this way is commanded to the motor 4 of the engine 1 shown in FIG. 1, and the throttle valve 5 is set to the target throttle opening TVot.
The output of the engine 1 is controlled by controlling the opening degree such that

The gradient resistance addition rate α and the flag FLAG in FIG. 2 are determined by executing the program shown in FIG. First, at step 41, it is checked whether the accelerator pedal depression amount APS is 0 or not.
While the accelerator pedal depression amount APS is not 0, that is, while the accelerator pedal is being depressed, the gradient resistance addition rate α is set to a large value 0.8 in step 42, and then the flag FLAG is set to 1 in step 43 and the control is terminated. I do.

While it is determined in step 41 that the accelerator pedal depression amount APS is 0, that is, while the accelerator pedal is released, in step 44 the gradient resistance addition rate α
Is set to, for example, a small 0.3, so that the adder 34 in FIG. 2 adds the gradient resistance addition (Rf) to the flat road target driving force Tdo.
× α) so that the target driving force Tdt is always smaller than the running resistance of the vehicle including the slope resistance corresponding to the uphill slope.

In the next step 45, it is determined from the road information from the navigation system 20 shown in FIG. 1 whether or not the running road is a winding road. In addition,
In determining whether or not the road is a winding road, instead of using the road information from the navigation system 20, when the accumulation of the time during which the steering angle has exceeded the predetermined angle within the predetermined time has exceeded the predetermined value on both the left and right, the winding is performed. The road may be determined. When it is determined in step 45 that the road is not a winding road, the flag FLAG is set to 0 in step 46.

If it is determined in step 45 that the road is a winding road, it is checked in step 47 whether the timer TM has been set. This timer TM is for measuring the accelerator pedal depression amount APS = 0 (accelerator pedal release) in step 41 and measuring the elapsed time from the moment when the winding road is judged in step 45. At 48, a predetermined time (for example, 5 seconds) is set, and the value is decremented as time elapses. Here, the above-mentioned predetermined time (for example, 5 seconds) set in the timer TM is a time for detecting that the driver wants to sufficiently decelerate or stop the vehicle, and is an empirical rule. Can be determined arbitrarily.

In step 49, it is determined whether or not the timer TM, which has set the predetermined time (for example, 5 seconds) as described above, has become 0, that is, the state in which the accelerator pedal is released on the winding road. It is checked whether or not the operation has continued for 5 seconds. If the operation has continued, the flag FLAG is set to 0 in step 46, and until that time, the flag FLAG is set to 1 in step 43.

By determining the gradient resistance addition rate α and the flag FLAG as described above, the output control of the engine 1 and the shift control of the continuously variable transmission 2 in FIG. . That is, as described above with reference to FIG. 3, since the gradient resistance addition rate α is large 0.8 when the accelerator pedal is depressed, the gradient resistance addition (Rf × α) is sufficiently large, and this is equal to the flat road target driving force Tdo. The target driving force Tdt obtained by adding to the above is a value that enables the vehicle to run sharply without running out of driving force even on an uphill road. Further, since the flag FLAG is 1 when the accelerator pedal is depressed, the target throttle opening selector 38 outputs the required throttle opening TVOo as the target throttle opening TVot. Therefore, the output control of the engine 1 and the shift control of the continuously variable transmission 2 in FIG.
The target driving force Tdt added by the added amount of the gradient resistance (Rf × α) is generated at the lowest fuel efficiency, and it is possible to realize the sharp running on the uphill road with the lowest fuel efficiency.

As described above with reference to FIG. 3, since the gradient resistance addition rate α is small in the released state of the accelerator pedal, as shown in FIG. 3, the flat road target driving force Tdo is added to the gradient resistance addition (Rf × The target driving force Tdt obtained by adding α) becomes smaller than the running resistance of the vehicle including the slope resistance corresponding to the uphill slope. On the other hand, when the accelerator pedal is released, the flag FLAG is determined depending on whether or not the vehicle is on the winding road as described above with reference to FIG.
Therefore, the target throttle opening selector 3 shown in FIG.
8 is the throttle opening value 0 and the target throttle opening TVot.
Output as

For this reason, when the accelerator pedal is released on the non-winding road, the speed change control of the continuously variable transmission 2 in FIG. 2 is performed with the target driving force Tdt added by the gradient resistance addition (Rf × α). The target speed ratio It correspondingly determined is executed so as to be realized, but the output control of the engine 1 in FIG. 2 is performed at the throttle opening TVO = 0 regardless of the target driving force Tdt, as in the case where the accelerator pedal is depressed. The driving force increase control on a smooth uphill road is stopped. Therefore, if the accelerator pedal is released on a non-winding road, even if the accelerator pedal is released, the driving force increase control according to the gradient of the ascending road is stopped, and the vehicle is driven when the accelerator pedal is released to decelerate or stop the vehicle on the ascending road. It is possible to eliminate the problem that the power increase control is not continued and the driving feeling becomes uncomfortable, and the fuel consumption is deteriorated due to an unnecessary increase in engine output.

When the accelerator pedal is released on the winding road, the timer TM is released as described above with reference to FIG.
The flag FLAG is set to 1 until a predetermined time (for example, 5 seconds) is measured, and then the flag FLAG is set to 0, so that a predetermined time (for example, 5 seconds) elapses from the moment when the accelerator pedal is released on the winding road. In the meantime, the output control of the engine 1 and the shift control of the continuously variable transmission 2 in FIG.
Thereafter, the throttle opening TVO is set to 0, and the driving force increase control is stopped.

Accordingly, when the uphill road is a winding road, even when the accelerator pedal is released, a predetermined time (for example, 5 seconds) elapses from the moment when the accelerator pedal is released.
In order to continue the driving force increase control according to the gradient of the ascending road, the driving force increase control may be stopped when approaching the corner of the curved road and temporarily releasing the accelerator pedal during the uphill traveling on the winding road. This can prevent the engine output from rising slightly when the accelerator pedal is depressed immediately afterwards, and the driver may feel a delay in acceleration after passing a curved road corner. Can be avoided.

After a lapse of a predetermined time (for example, 5 seconds) from the moment when the accelerator pedal is released, the throttle opening T
In order to stop the above driving force increase control by setting VO = 0,
It is possible to avoid the adverse effect of not being able to obtain the required deceleration when you want to perform sufficient deceleration or when you want to stop, if the continuation of the driving force increase control when releasing the accelerator pedal on the winding road continues forever it can.

By the way, during the driving force increase control continued as described above when the accelerator pedal is released on the winding road, the gradient resistance addition rate α is set to a small 0.3 as described above with reference to FIG. As described above, the target driving force Tdt obtained by adding the gradient resistance addition (Rf × α) to the flat road target driving force Tdo becomes smaller than the running resistance of the vehicle including the gradient resistance corresponding to the uphill road gradient. It is possible to eliminate the uncomfortable feeling that the vehicle accelerates despite the release of the pedal, and it is possible to accelerate quickly when the accelerator pedal is depressed again thereafter.

The above operation will be additionally described with reference to FIG. 6. In FIG. 6, the accelerator pedal depression amount A is maintained until the instant t4.
It is assumed that the vehicle is traveling on a winding road in which the PS changes in a short cycle, and that the vehicle is traveling on a non-winding road in which the accelerator pedal depression amount APS changes in a long cycle after the instant t4.
During any running, the gradient resistance addition rate α is 0.8 and the flag FLAG is 1 at the instant t1 when the accelerator pedal is depressed, between the instants t2 and t3, and between the instants t4 and t5. On an uphill road, the target driving force Tdt obtained by adding the gradient resistance addition (Rf × α) and the flat road target driving force Tdo becomes large, and the target throttle opening selection unit 38 is set by the flag FLAG = 1. Since the required throttle opening TVOo corresponding to the large target driving force Tdt is set to the target throttle opening TVot, the throttle opening TVO is controlled as shown by a solid line in FIG. Become. When the vehicle is traveling on a flat road, the gradient resistance Rf is zero, and the gradient resistance addition (Rf × α) is also zero. Therefore, the target driving force Tdt is reduced accordingly, and the throttle opening TVO is indicated by a broken line in FIG. As shown in the figure, it is possible to prevent the driving force increase control from being performed needlessly.

Between the instants t1 and t2 when the accelerator pedal is released during running on the winding road and between the instants t3 and t4, the gradient resistance addition rate α is 0.3, and the flag FLAG indicates the accelerator pedal release instant t1, t1. Since it is 1 during the set time (5 seconds) of the timer TM from t3, the target driving force Tdt obtained by adding the gradient resistance addition (Rf × α) and the flat road target driving force Tdo on an uphill road. Correspondingly, the throttle opening TVO is controlled as shown by the solid line in FIG. For this reason, even when the accelerator pedal is released during running on a winding road, the driving force increase control according to the gradient of the uphill road is continued, and during the uphill running on the winding road, the accelerator pedal is temporarily released by reaching the corner of the curved road It is possible to prevent the rise of the engine output at the instant t2 at which the accelerator pedal is depressed immediately after the start of the operation from being delayed.

During the continuation of the driving force increase control, in order to reduce the gradient resistance addition rate α to a small value of 0.3, the target obtained by adding the gradient resistance addition (Rf × α) to the flat road target driving force Tdo. The driving force Tdt becomes smaller than the running resistance of the vehicle including the slope resistance corresponding to the slope of the ascending road, so that the uncomfortable feeling that the vehicle accelerates despite the release of the accelerator pedal can be eliminated, and the subsequent accelerator pedal release. Rapid acceleration is possible when the driver steps again.

However, even if the driving force increase control is continued even when the accelerator pedal is released on the winding road, the gradient resistance Rf is 0 on the flat road, so that the gradient resistance is added (Rf × α). Is also 0, and the target driving force Tdt also becomes 0 in accordance with the accelerator pedal depression amount APS = 0, so that the throttle opening TVO is set to 0 as shown by the broken line in FIG. 6, and the driving force increases wastefully on a flat road. It is possible to prevent the control from being continued.

On the other hand, if the driving force increase control when the accelerator pedal is released during running on a winding road is going to continue for more than the set time (5 seconds) of the timer TM, the timer is started from the accelerator pedal release instant t3. As seen immediately after the set time of TM (5 seconds) has elapsed, the flag FLAG becomes 0 and the throttle opening TVO is set to 0 as shown by the solid line, and the driving force increase control on the uphill road is stopped at that instant. I do. Therefore, the driving force increase control when the accelerator pedal is released during running on the winding road does not continue for more than the set time (5 seconds) of the timer TM, and it is desired to perform sufficient deceleration or to stop the vehicle. You can get the required deceleration when you are.

At the instant t5 when the accelerator pedal is released during running on a non-winding road, the flag FLAG becomes 0, so that the target driving force Tdt becomes 0 regardless of whether the vehicle is on an uphill road or a flat road, and the throttle opening degree is increased. TVO is set to 0 as shown by the solid line (uphill road) and the broken line (flat road) in FIG. Therefore, the driving force increase control is stopped when the accelerator pedal is released even when traveling on an uphill road, and the driving force increase control may be continued when the accelerator pedal is released to decelerate or stop the vehicle on the uphill road. Thus, it is possible to solve the problem that the driving feeling becomes uncomfortable, and the fuel consumption is deteriorated due to an unnecessary increase in engine output.

In any case, the target driving force Tdt is set to a value obtained by adding the flat road target driving force Tdo and the gradient resistance addition amount (Rf × α) during the traveling on the uphill road. In this case, it is advantageous that the driving force increase control during traveling on an uphill road can be easily realized only by changing the method of determining the target driving force. Further, since the driving force increase control at the time of releasing the accelerator pedal is stopped only by completely closing the engine throttle opening corresponding to the release of the accelerator pedal, the driving force increasing control for traveling on an uphill road at the time of releasing the accelerator pedal is performed. This is advantageous because it can be easily stopped.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a power train of a vehicle equipped with a continuously variable transmission equipped with a driving force control device according to an embodiment of the present invention, together with a control system thereof.

FIG. 2 is a functional block diagram of a continuously variable transmission executed by a controller according to the embodiment in a shift control and an engine throttle opening degree control;

FIG. 3 is a flowchart showing a program for determining a gradient resistance addition rate and a target throttle opening selection flag used in the shift control and the throttle opening control of FIG. 2;

FIG. 4 is a characteristic diagram illustrating change characteristics of a vehicle driving force required when traveling on a flat road.

FIG. 5 is a change characteristic diagram showing a target gear ratio of a continuously variable transmission that achieves a target driving force with minimum fuel consumption.

FIG. 6 is a time chart showing a control mode of a throttle opening degree when the traveling road is switched from a winding road to a non-winding road in comparison with traveling on an uphill road and traveling on a flat road. is there.

[Explanation of symbols]

 Reference Signs List 1 engine 2 continuously variable transmission 3 accelerator pedal 4 motor 5 electronically controlled throttle valve 6 torque converter 7 primary pulley 8 secondary pulley 9 V belt 10 final drive gear set 11 differential gear device 12 hydraulic actuator 13 controller 14 accelerator pedal operation amount sensor 15 Crank angle sensor 16 Throttle opening sensor 17 Transmission input rotation sensor 18 Transmission output rotation sensor 19 Vehicle speed sensor 20 Navigation system 31 Flat road target driving force calculation unit 32 Slope resistance calculation unit 33 Multiplier 34 Adder 35 Target gear ratio calculation Section 36 Target engine output torque calculation section 37 Required throttle opening calculation section 38 Target throttle opening selection section

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16H 61/02 F16H 61/02 // F16H 59:06 59:06 59:18 59:18 59:24 59 : 24 59:66 59:66 59:70 59:70 63:06 63:06 F term (reference) 3G065 AA04 CA19 DA05 DA06 DA15 EA04 EA07 FA04 GA10 GA11 GA31 GA41 GA46 GA49 HA21 HA22 JA04 JA09 JA11 KA02 3G093 AA06 BA02 BA15 BA23 CB04 CB10 DA01 DA06 DB05 DB11 DB18 EA02 EA09 EB03 EC02 3G301 HA01 JA04 JA11 KB02 KB07 LA03 LC03 NA08 ND03 NE03 PA01Z PA11Z PE01Z PF01Z PF03Z PF08Z PF15Z 3J552 MA07 MA12 NA01 NB01 RB04 RB12 TB12 RB04 RB04 VA39Y VA42Z VA74Y VA74Z VA76W VB01Z VB08W VB09W VB09Z VC01Z VC02W VC03W VC03Z VD02Z VD04W VD14Z VE03W VE04W VE08Z

Claims (5)

[Claims] An engine capable of arbitrarily changing the output torque by a factor other than the operation of the accelerator pedal and a power train which is a combination with an automatic transmission are mounted, and at least the output torque of the engine is adjusted in accordance with operating conditions. In a vehicle that controls the vehicle so that a predetermined target driving force is achieved, a driving force increase control is performed to increase the driving force according to the gradient of the uphill road when the vehicle is traveling on an uphill road. A driving force control device for a vehicle, wherein the driving force increase control is stopped, and when the uphill road is a winding road, the driving force increase control is continued even when the accelerator pedal is released. 2. The driving force increase control according to claim 1, wherein the target driving force is set to a target driving force to which a gradient resistance determined according to the gradient of the uphill road is added during traveling on the uphill road. A driving force control device for a vehicle, wherein the driving force control device is configured to perform the driving force control. 3. The system according to claim 1, wherein the driving force increase control at the time of releasing the accelerator pedal is stopped only by fully closing the engine throttle opening in response to the release of the accelerator pedal. Vehicle driving force control device. 4. The driving force according to claim 1, wherein the driving force when the driving force increase control is continued because the vehicle is running on a winding road even when the accelerator pedal is released is determined according to the gradient of the uphill road. A driving force control device for a vehicle, wherein the driving resistance control device is smaller than a running resistance of a vehicle including a gradient resistance. 5. The accelerator pedal according to claim 1, wherein a continuation time when the driving force increase control is continued because the vehicle is running on a winding road even when the accelerator pedal is released is limited. A driving force control device for a vehicle, wherein the driving force increase control is stopped after a set time has elapsed from the release of the vehicle.