JP7104371B2 - Vehicle control device - Google Patents

Description

The present invention relates to a vehicle control device, and more particularly to a vehicle control device in which the rear wheels are driven.

Japanese Patent No. 6168484 (Patent Document 1) describes an engine control device. In this engine control device, when the steering of the vehicle is operated, the torque generated by the engine is reduced to stabilize the behavior of the vehicle and to make the vehicle turn according to the driver's intention. ing. Further, in the engine control device described in Patent Document 1, when the torque generated by the engine is reduced based on the steering operation, the torque is reduced by retarding the ignition timing by the ignition device of the engine.

Japanese Patent No. 6168484

However, when the inventor of the present invention tried to apply a control for reducing the torque generated by the engine as the vehicle is steered, as described in Patent Document 1, to a rear-wheel drive vehicle, Patent Document 1 describes. It was not possible to obtain the effects of improving the steering stability and the responsiveness of the vehicle behavior obtained in the present invention.

That is, the present inventor has applied a control for reducing the torque generated by the engine as the vehicle is steered, as described in Patent Document 1, as the vehicle attitude control. However, when such conventionally known vehicle attitude control is applied to a rear-wheel drive vehicle, it is possible to obtain an effect such as improvement in vehicle responsiveness, which has been obtained in a front-wheel drive vehicle. There wasn't. As a result of the inventor's diligent research to solve this newly discovered problem, in a rear-wheel drive vehicle, surprisingly, the driving torque of the vehicle is increased in response to steering by the driver. As a result, it became clear that the vehicle responsiveness and linear feeling were improved.

In general, when the torque generated by the engine is reduced to give a deceleration to the vehicle, the inertial force acting on the center of gravity of the vehicle causes a pitching motion in which the front side of the vehicle sinks, so that the load on the front wheels, which are the steering wheels, increases. Therefore, it was thought that the responsiveness to the steering operation would be improved. However, in a rear-wheel drive vehicle, when the drive torque of the rear wheels is reduced to give the vehicle a deceleration, in addition to the above inertial force, the vehicle body is tilted backward from the rear wheels via the suspension (rear side is tilted). The force (to sink) is generated momentarily. Since this momentary force acts to reduce the front wheel load, in a rear-wheel drive vehicle, even if the vehicle is decelerated in response to steering by the driver, the vehicle responsiveness and linear feeling are as expected. It is probable that it was not possible to improve.

On the contrary, in a rear-wheel drive vehicle, by increasing the drive torque of the rear wheels, a force that tilts the vehicle body forward (sinks the front side) from the rear wheels via the suspension acts momentarily. As the front wheel load increases, the vehicle responsiveness and linear feeling are considered to be improved. That is, in a rear-wheel drive vehicle, when acceleration is applied by increasing the drive torque of the rear wheels, an inertial force that tilts the vehicle body backward and a momentary force that tilts the vehicle body forward are generated, but the vehicle response to the steering operation. It is considered that the momentary force to tilt the car body forward contributes predominantly to the sexuality and linear feeling.

The present inventor sets the increased torque so as to increase the basic torque based on the steering angle-related value of the steering device mounted on the vehicle, so that the front wheel load increases due to the above-mentioned momentary force. It was found that the vehicle responsiveness to steering operation and the linear feeling can be improved. However, it is difficult to instantaneously increase the torque generated by the engine based on the steering operation of the driver. Control to reduce the engine torque based on the steering operation of the driver, as in the conventional vehicle attitude control, can be realized relatively easily by delaying the ignition timing of the spark plug of the engine. Here, since the ignition timing of the engine is generally set to the time when the generated torque becomes the highest, it is difficult to increase the engine torque by advancing or retarding the ignition timing.

Further, the increase in the torque generated by the engine can be realized by increasing the amount of air supplied into the cylinder of the engine and increasing the amount of fuel injected by the fuel injection valve. However, the increase in the generated torque by this method has poor responsiveness, and the time lag from the increase in the supply air amount to the increase in the actually generated torque is not constant, so the time required for vehicle attitude control. It is difficult to increase the torque accurately.

Therefore, according to the present invention, even when the vehicle in which the rear wheels are driven by the engine is controlled, the engine torque can be increased at an appropriate time, and the responsiveness or linear feeling of the vehicle to the steering operation is improved. It is an object of the present invention to provide a vehicle control device capable of providing a vehicle control device capable of providing a vehicle control device.

In order to solve the above-mentioned problems, the present invention comprises a vehicle control device in which the rear wheels are driven, a steering device for steering the front wheels of the vehicle, an engine for driving the rear wheels of the vehicle, and the like. An intake throttle valve provided in the intake passage of the engine, an intake pressure sensor provided in the intake passage on the downstream side of the intake throttle valve, a fuel injection valve, and a steering angle-related value related to the steering angle of the steering device. It has a steering angle related value detection sensor for detecting, a driving state sensor for detecting the driving state of the vehicle, and a controller for controlling the engine, and the controller is based on the driving state detected by the driving state sensor. When the steering angle-related value detected by the steering angle-related value detection sensor exceeds a predetermined start threshold value, an increased torque is set based on the steering angle-related value, and the engine starts the basic torque. The intake throttle valve and the fuel injection valve are configured to control the intake throttle valve and the fuel injection valve so as to generate a torque obtained by adding an increase torque to the above, and the controller is a differential pressure before and after the intake throttle valve detected by the intake pressure sensor. When is small, the starting threshold is set lower than when the differential pressure is large.

In the present invention configured as described above, the controller is set based on the basic torque set based on the operating state and the steering angle related value by controlling the intake throttle valve and the fuel injection valve. The engine is generated with the torque obtained by adding the increased torque. The increased torque is set when the steering angle-related value becomes equal to or higher than a predetermined start threshold value. The controller sets the start threshold value lower when the differential pressure before and after the intake throttle valve is small than when the differential pressure is large.

When the intake throttle valve is opened in order to increase the torque generated by the engine, there is a time lag before the torque generated by the engine actually starts to increase in response to this. This time lag is short when the differential pressure before and after the intake throttle valve is large, and long when the differential pressure is small. That is, when the differential pressure before and after the intake throttle valve is large, if the opening degree of the intake throttle valve is increased, the air intake amount quickly increases based on the differential pressure before and after the intake throttle valve, so that the intake throttle valve is opened. Then, the torque starts to increase in a relatively short time. On the other hand, when the differential pressure before and after the intake throttle valve is small, the increase in the amount of air intake based on the differential pressure before and after the intake throttle valve is small, and the torque actually starts to increase after the intake throttle valve is opened. Will take longer.

As described above, the increase in torque for improving the responsiveness of the vehicle to the steering operation and the linear feeling needs to be executed promptly in response to the steering operation, so it is sufficient if the increase in the torque actually generated is delayed. The effect cannot be obtained. Further, if the time until the torque actually increases differs depending on the operating state of the engine, the variation in the improvement effect of the responsiveness of the vehicle and the linear feeling becomes large, which may give the driver a sense of discomfort.

According to the present invention configured as described above, when the differential pressure before and after the intake throttle valve detected by the intake pressure sensor is small, the start threshold value is set lower than when the differential pressure is large. As a result, when the differential pressure before and after the intake throttle valve is small, the increased torque is set early after the driver starts steering, so the time lag from the setting of the increased torque to the actual increase in torque is long. Even so, it is possible to increase the torque at an appropriate time. As a result, the responsiveness of the vehicle to the steering operation and the linear feeling can be sufficiently improved.

Furthermore, when the differential pressure before and after the intake throttle valve is small and the torque increase delay is likely to occur, the start threshold is lowered and the torque increase time is accelerated, so that the differential pressure before and after the intake throttle valve is small and large. After the driver starts steering, the timing difference when the torque actually increases becomes smaller. As a result, it is possible to suppress variations in the responsiveness of the vehicle and the effect of improving the linear feeling depending on the operating state of the engine, and it is possible to make it difficult for the driver to feel a sense of discomfort.

In the present invention, preferably, the controller is configured to set the start threshold value lower when the opening degree of the intake throttle valve is large than when the opening degree is small.

When the opening degree of the intake throttle valve is large, the flow path resistance of the air flowing through the intake throttle valve becomes small, so that the differential pressure before and after the intake throttle valve tends to be small. According to the present invention configured as described above, when the opening degree of the intake throttle valve is large, the start threshold value is set low, so that the torque increase time is accelerated when the front-rear differential pressure of the intake throttle valve is small. It is possible to increase the torque generated at an appropriate timing.

In the present invention, preferably, the controller sets a larger torque increase value for the same steering angle-related value when the differential pressure before and after the intake throttle valve is small than when the differential pressure is large. It is configured.

According to the present invention configured as described above, when the differential pressure before and after the intake throttle valve is small, the value of the increased torque is set to be larger than when the differential pressure is large. As a result, when the differential pressure before and after the intake throttle valve is small, a large increase torque can be set by a slight change in the steering angle related value, and the torque increase time can be accelerated, and at an appropriate timing. The generated torque can be increased.

In the present invention, preferably, the controller is configured so that when the opening degree of the intake throttle valve is large, the value of the increased torque with respect to the same steering angle-related value is set larger than when the opening degree is small. ing.

According to the present invention configured as described above, when the opening degree of the intake throttle valve is large, the value of the increased torque with respect to the same steering angle-related value is set larger than when the opening degree is small. As a result, when the opening degree of the intake throttle valve is large, a large increase torque can be set by a slight change in the steering angle-related value, and the torque increase time can be accelerated, and the torque increase occurs at an appropriate timing. The torque can be increased.

In the present invention, preferably, the engine is provided with a supercharger, and the controller has a small difference pressure between the supercharging pressure by the supercharger and the pressure on the downstream side of the intake throttle valve detected by the intake pressure sensor. Is configured to set the start threshold lower than when the differential pressure is large.

When the engine is equipped with a supercharger, the differential pressure before and after the intake throttle valve can be obtained from the difference between the boost pressure and the pressure on the downstream side of the intake throttle valve. According to the present invention configured as described above, when the differential pressure between the boost pressure and the pressure on the downstream side of the intake throttle valve is small, the start threshold value is set low, so that a supercharger is provided. It is possible to increase the torque generated at an appropriate timing even in the engine.

In the present invention, preferably, the engine is provided with a spark plug, and the controller is configured to retard the ignition timing of the spark plug based on the increment of the intake air amount by setting the increased torque.

The net torque generated by the engine is the torque generated by the combustion of fuel minus the torque required to draw air from the intake flow path into the cylinder (pump loss). Here, when the intake throttle valve is opened to increase the torque generated by the engine, the flow path resistance in the intake throttle valve decreases, so that the pump loss decreases and the net torque increases. The increased torque set based on the steering angle-related value can be covered by the reduction in pump loss. On the other hand, since a gasoline engine is normally operated at a constant stoichiometric air-fuel ratio, when the intake throttle valve is opened and the intake air amount is increased, the fuel injection amount is also increased accordingly, which is generated by the combustion of fuel. The torque also increases. In this way, when the net torque increase due to the decrease in pump loss and the torque increase generated by the combustion of fuel are superimposed, the torque increase may become excessive. According to the present invention configured as described above, the ignition timing of the spark plug is retarded based on the increment of the intake air amount by setting the increased torque, so that the opening degree of the intake throttle valve is increased to cause pump loss. When it is reduced, the torque generated by the combustion of fuel can be reduced. As a result, it is possible to suppress an excessive increase in torque.

The present invention is a vehicle control device in which the rear wheels are driven, and is provided in a steering device for steering the front wheels of the vehicle, an engine for driving the rear wheels of the vehicle, and an intake passage of the engine. An intake throttle valve, a throttle opening sensor that detects the opening degree of the intake throttle valve, a fuel injection valve, a steering angle-related value detection sensor that detects a steering angle-related value related to the steering angle of the steering device, and the like. It has a driving state sensor that detects the driving state of the vehicle and a controller that controls the engine. The controller sets the basic torque based on the driving state detected by the driving state sensor, and the steering angle related value. When the steering angle-related value detected by the detection sensor becomes equal to or higher than the predetermined start threshold value, the increased torque is set based on the steering angle-related value so that the engine generates the torque obtained by adding the increased torque to the basic torque. In addition, the controller is configured to control the intake throttle valve and the fuel injection valve, and when the opening degree of the intake throttle valve detected by the throttle opening sensor is large, the opening degree is smaller than when the opening degree is small. Is also characterized in that it is configured to set a low start threshold.

Further, the present invention is a vehicle control device in which the front wheels are steered by a steering device and the rear wheels are driven by an engine, and the steering angle-related value related to the steering angle of the steering device is equal to or higher than a predetermined start threshold value. When the vehicle attitude control means for increasing the torque generated by the engine and the differential pressure between the upstream side and the downstream side of the intake throttle valve of the engine are small, the start threshold value is set lower than when the differential pressure is large. It is characterized by having a threshold setting means.

Further, the present invention is a vehicle control device in which the front wheels are steered by a steering device and the rear wheels are driven by an engine, and the steering angle-related value related to the steering angle of the steering device is equal to or higher than a predetermined start threshold value. At that time, the vehicle attitude control means for increasing the torque generated by the engine and the threshold setting means for setting the start threshold lower when the opening of the intake throttle valve of the engine is large than when the opening is small. It is characterized by having.

According to the vehicle control device of the present invention, even when the vehicle in which the rear wheels are driven by the engine is controlled, the engine torque can be increased at an appropriate time, and the responsiveness or linearity of the vehicle to the steering operation can be increased. The feeling can be improved.

It is a block diagram which shows the whole structure of the vehicle to which the control device of the vehicle according to the embodiment of this invention is applied. It is a schematic block diagram of the engine system to which the control device of the vehicle according to the embodiment of this invention is applied. It is a block diagram which shows the electric structure of the control device of a vehicle by embodiment of this invention. It is a flowchart of the vehicle attitude control process in the vehicle control device according to the embodiment of this invention. It is a flowchart of the threshold value setting / increase torque setting process in the vehicle control device according to the embodiment of this invention. It is a map which defined the start threshold value of the vehicle attitude control in the vehicle control device according to the embodiment of this invention. It is a map which showed the relationship between the additional acceleration and the steering speed in the control device of a vehicle according to the embodiment of this invention. It is a map for correcting the additional acceleration in the control device of a vehicle according to the embodiment of this invention. It is a figure which shows the relationship between the opening degree of the throttle valve in the control device of a vehicle by embodiment of this invention, and the pressure difference before and after the opening degree. It is a map which shows the retardation amount of the ignition timing with respect to the intake increase amount based on the setting of the increase torque in the vehicle control device by embodiment of this invention. It is a time chart which shows an example of the operation of the control device of a vehicle by embodiment of this invention. It is a time chart which shows an example of the operation of the control device of a vehicle by embodiment of this invention.

Hereinafter, the vehicle control device according to the embodiment of the present invention will be described with reference to the accompanying drawings.
<System configuration>
First, with reference to FIG. 1, a vehicle to which the vehicle control device according to the embodiment of the present invention is applied will be described. FIG. 1 is a block diagram showing an overall configuration of a vehicle to which a vehicle control device according to an embodiment of the present invention is applied.

In FIG. 1, reference numeral 200 indicates a vehicle equipped with a vehicle control device according to the present embodiment. Left and right front wheels 202a, which are steering wheels, are provided on the front portion of the vehicle body of the vehicle 200, and left and right rear wheels 202b, which are drive wheels, are provided on the rear portion of the vehicle body. The front wheels 202a and the rear wheels 202b of the vehicle 200 are supported by the suspension 203 with respect to the vehicle body, respectively. Further, an engine 10 which is a prime mover for driving the rear wheels 202b is mounted on the front portion of the vehicle body of the vehicle 200. In this embodiment, the engine 10 is a gasoline engine. Further, in the present embodiment, the vehicle 200 is a so-called FR vehicle in which the rear wheels 202b are driven by the engine 10 mounted on the front portion of the vehicle body via the transmission 204a, the propeller shaft 204b, and the differential gear 204c. The present invention can be applied to any vehicle in which the rear wheels are driven by the engine 10, such as a so-called RR vehicle in which the rear wheels 202b are driven by the engine 10 mounted on the rear portion of the vehicle body.

Further, the vehicle 200 is equipped with a steering device 207 including a steering wheel 206 (hereinafter, also simply referred to as “steering”), and the front wheels 202a of the vehicle 200 are based on the rotation operation of the steering wheel 206. It is designed to be steered (steering). Further, the vehicle 200 includes a steering angle sensor 40 which is a steering angle related value detection sensor for detecting the steering angle of the steering device 207, an accelerator opening sensor 30 for detecting the amount of depression of the accelerator pedal (accelerator opening), and a vehicle speed. It has a vehicle speed sensor 39 for detecting. The steering angle sensor 40 typically detects the rotation angle of the steering wheel 206, but may also detect the steering angle (tire angle) of the front wheels 202a in addition to or instead of the rotation angle. good. Each of these sensors outputs its own detection signal to the PCM (Power-train Control Module) 50, which is a controller.

Next, with reference to FIGS. 2 and 3, an engine system to which the vehicle control device according to the embodiment of the present invention is applied will be described. FIG. 2 is a schematic configuration diagram of an engine system to which a vehicle control device according to an embodiment of the present invention is applied. FIG. 3 is a block diagram showing an electrical configuration of a vehicle control device according to an embodiment of the present invention.

As shown in FIG. 2, the engine system 100 mainly consists of an intake passage 1 through which intake air (air) introduced from the outside passes, intake air supplied from the intake passage 1, and a fuel injection valve 13 described later. An engine 10 (specifically, a gasoline engine) that burns an air-fuel mixture with the supplied fuel to generate power for a vehicle, and an exhaust passage 25 that discharges exhaust gas generated by combustion in the engine 10 are provided. Have.

In the intake passage 1, in order from the upstream side, an air cleaner 3 that purifies the intake air introduced from the outside, a throttle valve 5 that adjusts the amount of intake air passing through (the amount of intake air), and the intake air supplied to the engine 10 are temporarily supplied. A surge tank 7 for storing the air is provided. On the other hand, the exhaust passage 25 is provided with exhaust purification catalysts 26a and 26b having an exhaust gas purification function, such as a NOx catalyst, a three-way catalyst, and an oxidation catalyst.

The engine 10 of the present embodiment is an in-line 4-cylinder engine including four cylinders 2 arranged in a straight line. The engine 10 mainly has an intake valve 12 that introduces the intake air supplied from the intake passage 1 into the combustion chamber 11, a fuel injection valve 13 that injects fuel toward the combustion chamber 11, and the combustion chamber 11. An ignition plug 14 that ignites the air-fuel mixture of the supplied intake air and fuel, a piston 15 that reciprocates by burning the air-fuel mixture in the combustion chamber 11, and a crank shaft 16 that is rotated by the reciprocating motion of the piston 15. It has an exhaust valve 17 for discharging the exhaust gas generated by the combustion of the air-fuel mixture in the combustion chamber 11 to the exhaust passage 25.

Further, the engine 10 sets the operating timings (corresponding to the phase of the valve) of the intake valve 12 and the exhaust valve 17 as the variable valve timing mechanism (Variable Valve Timing Mechanism) of the variable intake valve mechanism 18 and the variable exhaust valve mechanism. It is variably configured by 19. Various known types can be applied to the variable intake valve mechanism 18 and the variable exhaust valve mechanism 19, but the operation of the intake valve 12 and the exhaust valve 17 is performed by using, for example, an electromagnetic or hydraulic mechanism. The timing can be changed.

Further, the engine system 100 is provided with sensors 30 to 40 for detecting various states related to the engine system 100 (see FIGS. 2 and 3). The accelerator opening sensor 30, the vehicle speed sensor 39, and the steering angle sensor 40 are as described above. The air flow sensor 31 detects the amount of intake air corresponding to the flow rate of the intake air passing through the intake passage 1. The throttle opening sensor 32 detects the throttle opening, which is the opening of the throttle valve 5. The pressure sensor 33 detects an intake manifold pressure (intake manifold pressure) corresponding to the pressure of the intake air supplied to the engine 10. The crank angle sensor 34 detects the crank angle (corresponding to the engine speed) of the crankshaft 16. The crank angle sensor 34 corresponds to an engine speed sensor. The water temperature sensor 35 detects the water temperature, which is the temperature of the cooling water that cools the engine 10. The atmospheric pressure sensor 36 measures the atmospheric pressure. The cam angle sensors 37 and 38 detect the operation timing including the closing timing of the intake valve 12 and the exhaust valve 17, respectively. Each of these various sensors 30 to 40 outputs a detection signal corresponding to the detected parameter to the PCM 50.

The PCM 50 controls the components in the engine system 100 based on the detection signals input from the various sensors 30 to 40 described above. Specifically, as shown in FIG. 3, the PCM 50 supplies a control signal to the throttle valve 5, controls the opening / closing timing and the throttle opening of the throttle valve 5, and supplies the control signal to the fuel injection valve 13. The fuel injection amount and the fuel injection timing are controlled, a control signal is supplied to the ignition plug 14, the ignition timing is controlled, and a control signal is supplied to each of the variable intake valve mechanism 18 and the variable exhaust valve mechanism 19. , Controls the operation timing of the intake valve 12 and the exhaust valve 17.

Each component of these PCM50s includes one or more processors and various programs that are interpreted and executed on the processor (including a basic control program such as an OS and an application program that is started on the OS and realizes a specific function). , And a computer equipped with an internal memory such as a ROM or RAM for storing programs and various data.

In one example, the vehicle control device in the present invention is mainly composed of an engine 10, a steering device 207, a steering angle sensor 40, an accelerator opening sensor 30, a vehicle speed sensor 39, and a PCM 50. In another example, the vehicle control device in the present invention is configured by a PCM50, and in this example, the PCM50 functions as a vehicle attitude control means and a threshold setting means in the present invention.

Further, the accelerator opening sensor 30 and the vehicle speed sensor 39 correspond to a driving state sensor that detects the driving state of the vehicle 200. Further, the steering angle sensor 40 corresponds to a steering angle-related value sensor that detects a steering angle-related value related to the steering angle of the steering device 207. In the following, an embodiment in which the steering speed is used as the steering angle-related value will be illustrated. This steering speed is obtained by the PCM 50 from the steering angle detected by the steering angle sensor 40. In this case, the steering angle-related value sensor is composed of the steering angle sensor 40 and the PCM 50.

<Vehicle attitude control>
Next, in the present embodiment, the control contents implemented by the PCM 50 to control the attitude of the vehicle 200 (vehicle attitude control) will be described. First, with reference to FIG. 4, the overall flow of the vehicle attitude control process performed by the PCM 50 in the present embodiment will be described. FIG. 4 is a flowchart of vehicle attitude control processing according to the embodiment of the present invention.

The vehicle attitude control process of FIG. 4 is activated when the ignition of the vehicle 200 is turned on and the power is turned on to the PCM 50, and is repeatedly executed at a predetermined cycle (for example, 50 ms).
When the vehicle attitude control process is started, as shown in FIG. 4, in step S1, the PCM 50 acquires various sensor information regarding the operating state of the vehicle 200. Specifically, the PCM 50 corresponds to the steering angle detected by the steering angle sensor 40, the accelerator opening degree detected by the accelerator opening sensor 30, the vehicle speed detected by the vehicle speed sensor 39, and the crank angle detected by the crank angle sensor 34. The detection signals output by the various sensors described above, including the engine speed and the gear stage currently set in the transmission 204a of the vehicle 200, are acquired as information on the operating state.

Next, in step S2, the PCM 50 sets the target acceleration based on the operating state of the vehicle 200 acquired in step S1. Specifically, the PCM50 has an acceleration corresponding to the current vehicle speed and gear stage from an acceleration characteristic map (created in advance and stored in a memory or the like) defined for various vehicle speeds and various gear stages. Select the characteristic map and set the target acceleration corresponding to the current accelerator opening with reference to the selected acceleration characteristic map.

Next, in step S3, the PCM 50 determines the basic torque that the engine 10 should generate in order to achieve the target acceleration set in step S2. In this case, the PCM 50 determines the basic torque within the range of torque that can be output by the engine 10 based on the current vehicle speed, gear stage, road surface gradient, road surface μ, and the like.

Further, in parallel with the processes of steps S2 and S3, the threshold value setting process is executed in step S4. As will be described later, the PCM 50 executes an increase torque setting process for setting a torque (increased torque) for adding acceleration to the vehicle 200 based on the steering operation. In step S4, a process of changing the threshold value of the steering operation according to the operating state, which starts adding the acceleration by the increased torque, is executed. The threshold value setting process in step S4 will be described later with reference to FIGS. 5 and 6.

Next, in step S5, the increase torque setting process is executed. That is, the PCM 50 sets an increased torque for increasing the basic torque according to the increase in the steering angle of the steering device 207, that is, according to the turning operation of the steering. In the present embodiment, the PCM 50 controls the vehicle posture by temporarily increasing the torque and adding acceleration to the vehicle 200 when the steering is turned. The increase torque setting process in step S5 will be described later with reference to FIGS. 7 and 8.

After executing the processes of steps S2 and S3, the threshold setting process of step S4, and the increase torque setting process of S5, in step S6, the PCM50 is based on the basic torque set in step S3 and the increase torque set in step S5. , Set the final target torque. Specifically, the PCM 50 calculates the final target torque by adding the increased torque to the basic torque.

Next, in step S7, the PCM 50 sets the actuator control amount for realizing the final target torque set in step S6. Specifically, the PCM 50 determines various state quantities required to realize the final target torque based on the final target torque set in step S6, and based on those state quantities, each component of the engine 10. Set the control amount of each actuator that drives. In this case, the PCM 50 sets a limit value and a limit range according to the state amount, and sets a control amount of each actuator so that the state value complies with the limit value and the limit by the limit range. Subsequently, in step S8, the PCM 50 outputs a control command to each actuator based on the control amount set in step S7.

Specifically, when the PCM50 sets the final target torque by adding the increasing torque to the basic torque in step S6, the PCM50 increases the throttle opening of the throttle valve 5 or after the bottom dead point. The intake air amount is increased by advancing the closing timing of the set intake valve 12. In this case, the PCM 50 increases the fuel injection amount by the fuel injection valve 13 in response to the increase in the intake air amount so that the predetermined air-fuel ratio is maintained.

After such step S8, the PCM 50 ends one process (vehicle attitude control process) of the flowchart shown in FIG.

<Threshold setting process / Increase torque setting process>
Next, the threshold value setting process and the increased torque setting process (see steps S4 and S5 in FIG. 4) according to the embodiment of the present invention will be described with reference to FIGS. 5 to 10. These processes set an increased torque for vehicle attitude control that is executed when the steering is turned.

FIG. 5 is a flowchart of the threshold value setting / increasing torque setting process according to the embodiment of the present invention. FIG. 6 is a map in which the start threshold value of vehicle attitude control according to the embodiment of the present invention is defined. FIG. 7 is a map showing the relationship between the applied acceleration and the steering speed according to the embodiment of the present invention. FIG. 8 is a map for correcting the additional acceleration according to the embodiment of the present invention.

When the increase torque setting process is started, in step S11 of FIG. 5, the PCM 50 controls the vehicle attitude using the start threshold map based on the detection signals of the pressure sensor 33 which is the intake pressure sensor and the atmospheric pressure sensor 36. Set a start threshold that defines the start condition of.

FIG. 6 shows a map that defines the relationship between the front-rear differential pressure (horizontal axis) and the start threshold value (vertical axis) of the throttle valve 5 which is an intake throttle valve. As shown in FIG. 6, in the present embodiment, the start threshold value is set to a larger value as the differential pressure before and after the throttle valve 5 becomes larger. That is, the PCM 50 obtains the differential pressure before and after the throttle valve 5 based on the detection signal of the pressure sensor 33 provided on the downstream side of the throttle valve 5 in the intake passage 1 and the detection signal of the atmospheric pressure sensor 36. , The value of the start threshold corresponding to this differential pressure is determined using the map shown in FIG. The circuit of the PCM 50 that determines the start threshold value in this way is a threshold value setting means that sets the start threshold value lower when the differential pressure between the upstream side and the downstream side of the throttle valve 5 of the engine 10 is small than when the differential pressure is large. Corresponds to.

As will be described later, the PCM 50 is configured to start vehicle attitude control when the driver starts cutting the steering wheel 206. That is, when the driver starts steering the steering wheel 206 and the steering angular velocity rises to a predetermined angular velocity, the vehicle attitude control is started. The value of the steering angular velocity [deg / sec] at which the vehicle attitude control is started is set as the start threshold value, and when the steering angular velocity rises to the start threshold value by cutting the steering wheel 206, the vehicle attitude control is started. The circuit of the PCM 50 that starts the vehicle attitude control in this way corresponds to the vehicle attitude control means that increases the torque generated by the engine 10 when the steering angular velocity of the steering device 207 becomes equal to or higher than a predetermined start threshold value.

Next, in step S12 of FIG. 5, it is determined by the PCM 50 whether or not the steering angle of the steering device 207 is increasing, and if the steering angle is increasing, the process proceeds to step S13. If the steering angle has not increased, one process of the flowchart shown in FIG. 5 is completed, and the process returns to the flowchart of FIG. In this case, the increased torque is not set, and the basic torque is set as it is as the final determined torque (step S6 in FIG. 4). The steering angle (absolute value) is increased by setting the state in which the vehicle 200 is traveling straight to zero and rotating the steering wheel 206 clockwise or counterclockwise from this state.

Next, in step S13, the PCM50 determines whether or not the steering angular velocity is equal to or greater than the start threshold value set in step S11, and if it is equal to or greater than the start threshold value, proceeds to step S14. When the steering angular velocity is less than the start threshold value, one process of the flowchart shown in FIG. 5 is completed, and the process returns to the flowchart of FIG. That is, the vehicle attitude control is not executed for a slight increase in the steering angle to the extent that the driver does not intend to steer, and excessive intervention of the vehicle attitude control is prevented. On the other hand, when the steering angular velocity is equal to or higher than the start threshold value, the process of step S14 or lower is executed, and the increased torque is set by the vehicle attitude control.

In step S14, the PCM 50 sets the additional acceleration based on the steering speed. This additional acceleration is an acceleration that should be applied to the vehicle 200 in response to the steering operation in order to control the vehicle posture according to the driver's intention.

Specifically, the PCM 50 sets an additional acceleration corresponding to the current steering speed based on the relationship between the additional acceleration shown in the map of FIG. 7 and the steering speed. In FIG. 7, the horizontal axis represents the steering angular velocity and the vertical axis represents the additional acceleration. As shown in FIG. 7, as the steering speed increases, the additional acceleration corresponding to the steering angular velocity gradually approaches a predetermined upper limit value A _max . That is, as the steering angular velocity increases, the additional acceleration increases, and the rate of increase in the amount of increase decreases. This upper limit value A _max is set to such an acceleration that the driver does not feel that there is control intervention even if acceleration is applied to the vehicle 200 according to the steering operation (for example, 0.5 m / s ² ≈ 0.05 G). ). When the steering angular velocity becomes equal to or higher than a predetermined threshold value, the additional acceleration is maintained at the upper limit value A _max .

Next, in step S15, the PCM 50 sets the increased torque required to realize the additional acceleration set in step S14.
Further, in step S16, the PCM 50 corrects the increased torque set in step S15. The correction of the increased torque is executed by multiplying the increased torque set in step S15 by the increased torque correction coefficient.

FIG. 8 is a map for setting the increased torque correction coefficient, and defines the relationship between the front-rear differential pressure (horizontal axis) and the increased torque correction coefficient (vertical axis) of the throttle valve 5. As shown in FIG. 8, in the present embodiment, the value of the increased torque correction coefficient is linearly set to a smaller value as the differential pressure before and after the throttle valve 5 increases. Therefore, in the present embodiment, when the differential pressure before and after the throttle valve 5 is small, the value of the corrected increased torque for the same steering angular velocity is larger than when the differential pressure is large.

Next, in step S17, it is determined whether or not the opening degree of the throttle valve 5 is equal to or greater than a predetermined opening degree. If the opening degree of the throttle valve 5 is less than the predetermined opening degree, the process proceeds to step S18, and if the opening degree is more than the predetermined opening degree, one process of the flowchart shown in FIG. 5 is completed.

When the opening degree of the throttle valve 5 is less than the predetermined opening degree, step S18 is executed, and in step S18, the retard angle of the ignition timing by the spark plug 14 is increased in accordance with the increase in the intake air amount based on the vehicle attitude control. The amount is set.

Here, FIG. 9 shows the relationship between the opening degree of the throttle valve 5 and the pressure difference before and after the opening degree. As shown in FIG. 9, when the opening degree of the throttle valve 5 is small, the flow path resistance of the throttle valve 5 is large, so that a relatively large pressure difference is generated before and after the throttle valve 5 (upstream side and downstream side). .. On the other hand, when the opening degree of the throttle valve 5 becomes large, the flow path resistance thereof becomes small, so that the pressure difference between the front and rear throttle valves 5 becomes small, and the pressure difference between the front and rear is substantially zero at an opening degree of about 60%. become.

On the other hand, the net torque generated by the engine 10 is the torque generated by subtracting the torque (pumping loss) required for sucking air into the cylinder of the engine 10 from the intake passage 1 from the torque generated based on the combustion of fuel. Become. Here, when the opening degree of the throttle valve 5 is large, the flow path resistance thereof is relatively small, so that the pumping loss is also small. On the other hand, when the opening degree of the throttle valve 5 is small, the flow path resistance thereof is relatively large, so that the pumping loss becomes large. Therefore, if the opening degree of the throttle valve 5 is increased from the state where the opening degree of the throttle valve 5 is small, the pumping loss is greatly reduced, and as a result, the net torque generated by the engine 10 is increased.

In addition, since the intake air amount is also increased by opening the throttle valve 5, the fuel injection amount is also increased in order to maintain the stoichiometric air-fuel ratio, which also increases the torque generated by the combustion of the fuel. Therefore, when the opening degree of the throttle valve 5 is increased from the state where the opening degree of the throttle valve 5 is small, the torque tends to increase excessively. Therefore, in the present embodiment, when the vehicle attitude control is executed in a state where the opening degree of the throttle valve 5 is small and the increased torque is set, the ignition timing by the spark plug 14 is retarded and the fuel is burned. It reduces the torque generated.

FIG. 10 is a map showing the amount of retardation of the ignition timing with respect to the amount of increase in intake air based on the setting of the increased torque. As shown in FIG. 10, in the present embodiment, the retard amount [deg] of the ignition timing is increased in proportion to the intake increase amount [cc] based on the setting of the increased torque. This prevents an excessive increase in torque in vehicle attitude control. Here, the torque generated by the combustion of the fuel in the engine 10 increases with a delay after the intake amount increases, whereas the increase in the net torque due to the decrease in the pumping loss has a small time lag, so that the vehicle attitude control It is suitable for increasing the torque for the purpose of.

In the present embodiment, the intake increase amount based on the increase torque setting is obtained based on the detection signal of the airflow sensor 31, but the intake increase amount can also be estimated based on the opening degree of the throttle valve 5. can. Further, in the present embodiment, when the opening degree of the throttle valve 5 is less than a predetermined value, the ignition timing is retarded, but in order to adjust the increased torque, the ignition timing is always retarded. The present invention can also be constructed. Further, depending on the characteristics of the throttle valve 5, it may not be necessary to delay the ignition timing for the purpose of adjusting the increased torque.

When the retard amount of the ignition timing is set in step S18, one process of the flowchart shown in FIG. 5 is completed, and the process returns to the flowchart of FIG. As described above, in the flowchart shown in FIG. 4, the final target torque is set by adding the increasing torque to the basic torque (step S6), and the control amount of each actuator for realizing this final target torque is set. (Step S7). Further, this control amount is commanded to each actuator (step S8), and the final target torque is output from the engine 10.

As described above, in the start threshold value / increase torque setting process shown in FIG. 5, the value of the start threshold value for determining whether or not the vehicle attitude control can be started is changed based on the differential pressure before and after the throttle valve 5. ing. That is, when the differential pressure between the front and rear of the throttle valve 5 is small, the start threshold value is set low (FIG. 6), so that the start threshold value is exceeded early when the driver starts steering, and the vehicle attitude control starts early. Will be done.

Here, in a state where the front-rear differential pressure of the throttle valve 5 is large, when the opening degree of the throttle valve 5 is increased, the air intake amount suddenly increases based on the pressure difference, whereas the front-rear differential pressure is small. In this state, after increasing the opening degree of the throttle valve 5, the time lag until the air intake amount actually increases becomes large. Therefore, when the front-rear differential pressure of the throttle valve 5 is large, the torque generated by the engine 10 rapidly increases when the vehicle attitude control is started, whereas the engine 10 is generated when the front-rear differential pressure is small. It takes longer for the torque to actually increase. In order to suppress such a timing shift until the torque rises, when the differential pressure between the front and rear of the throttle valve 5 is small, the start threshold value for starting the setting of the increased torque by vehicle attitude control is set low. , When the driver starts steering, the start threshold value is exceeded at an early stage, and the vehicle attitude control is started at an early stage.

Further, in step S16 of the flowchart shown in FIG. 5, the correction of the increased torque is executed, and when the differential pressure before and after the throttle valve 5 is small, the correction for the same steering angular velocity is performed as compared with the case where the differential pressure is large. The value of the increased torque of is increased. As described above, when the value of the increased torque is set to a large value, the PCM50 acts to increase the generated torque with the large torque value as the target value, so that the torque actually generated by the engine 10 is higher. It will start up rapidly. Therefore, when the differential pressure before and after the throttle valve 5 is small, the delay in torque increase can be suppressed.

In the present embodiment, the variation in the rise of the generated torque due to the differential pressure before and after the throttle valve 5 is suppressed by setting the start threshold (FIG. 6) and the increasing torque correction coefficient (FIG. 8). The present invention can also be configured so that variation is suppressed by only one of them.

Next, the operation of the vehicle control device according to the embodiment of the present invention will be described with reference to FIG.
FIG. 11 is a time chart showing an example of the operation of the vehicle control device of the present embodiment, in order from the upper stage, steering angle, steering angular velocity, final target torque, actually generated torque, pumping loss, throttle valve opening degree, intake air. Shows the amount. The time chart of FIG. 11 shows the operation when the amount of depression of the accelerator pedal by the driver is constant and the value of the basic torque is constant. Further, in the time chart of FIG. 11, when the amount of depression of the accelerator pedal is relatively large and the opening degree of the throttle valve 5 required to generate the basic torque is equal to or more than a predetermined value (step S17 in FIG. 5 → return). The action of) is shown.

First, since the steering angle is 0 when the driver is not steering, in the flowchart shown in FIG. 5, the processes of steps S11 → S12 → return are repeatedly executed, vehicle attitude control is not executed, and the increased torque is not executed. Is not set. Therefore, in this state, the basic torque is set as the final target torque (step S6 in FIG. 4) as it is, and is output from the engine 10.

Next, at time t1 in FIG. ₁₁ , when the driver starts steering, the steering angle (absolute value) starts to increase. Therefore, in the flowchart of FIG. 5, the processes of steps S11 → S12 → S13 → return are repeatedly executed. Become so. Further, when the steering angular velocity becomes equal to or higher than the start threshold value set in step S11, the vehicle attitude control is started. As a result, in the flowchart of FIG. 5, the processes of steps S11 → S12 → S13 → S14 → S15 → S16 → S17 → return are repeatedly executed.

When the vehicle attitude control is started, the PCM 50 controls each actuator so as to generate a torque obtained by adding an increasing torque to the basic torque as the final target torque. Specifically, the PCM 50 increases the opening degree of the throttle valve 5 in order to generate a torque obtained by adding an increasing torque to the basic torque. As a result, the amount of intake air sucked through the throttle valve 5 also increases, but there is a time lag after the opening degree of the throttle valve 5 is increased until the amount of intake air actually increases. The actual change in the intake air amount can be estimated from the detection signal of the air flow sensor 31 and the like.

As described above, since there is a time lag between the increase in the opening degree of the throttle valve 5 and the increase in the intake air amount, there is also a time lag in the increase in the torque actually generated by the engine 10. The fuel injection amount injected from the fuel injection valve 13 is also increased as the intake air amount is increased in order to maintain the stoichiometric air-fuel ratio.

Here, as described above, the time chart shown in FIG. 11 shows a case where the opening degree of the throttle valve 5 required to generate the basic torque is relatively large. Therefore, the differential pressure before and after the throttle valve 5 becomes relatively small (FIG. 9). As a result, the value of the vehicle attitude control start threshold value set using the map of FIG. 6 is set low, and the vehicle attitude control is started early. That is, in the steering angular velocity time chart of FIG. 11, when the differential pressure before and after the throttle valve 5 is large, the start threshold value set to Th1 [deg / sec] is lowered and changed to Th2 [deg / sec]. There is. As a result, when the start threshold value is set to Th1, the vehicle attitude control (setting of increased torque) started at time t3 is lowered to Th2, so that the time _{t 2 is} set earlier. It starts from.

In the time chart shown in FIG. 11, the change in each state quantity when the start threshold value of the vehicle attitude control is lowered to Th2 is shown by a solid line, and the case where Th1 is left without lowering the start threshold value is shown by a broken line. ing. As shown by the solid line in FIG. 11, by lowering the start threshold value of the vehicle attitude control to Th2, the increase in the opening degree of the throttle valve 5 is started early, and the intake air amount and the actually generated torque are also increased accordingly. Compared with the case where the start threshold value shown by the broken line is Th1, it starts to increase earlier.

Next, when the steering angular velocity becomes constant at time _t4 , the value of the additional acceleration set accordingly also becomes a constant value, and the value of the increased torque also becomes constant, so that the value of the final target torque also becomes constant (FIG. 11). The basic torque is constant). _On the other hand, there is a time lag between the increase in the intake air amount and the torque actually generated by the engine ₁₀ , and the intake air amount and torque corresponding to the final target torque are reached at the time t5 after the time t4. ..

Further, when the steering angular velocity starts to decrease at time t ₆ , the values of the set additional acceleration and the increased torque also start to decrease, and when the steering shifts to the steering at time t ₇ , the values of the set additional acceleration and the increased torque become. It is set to zero. On the other hand, the intake air amount and the actually generated torque of the engine ₁₀ start to decrease a little later than the time t6, and decrease to the intake air amount and the actually generated torque corresponding to the basic torque.

Further, as described above, the time chart shown in FIG. 11 shows a case where the opening degree of the throttle valve 5 required to generate the basic torque is relatively large, and even in a state where the increased torque is not set. The pumping loss is relatively small. Therefore, even if the opening degree of the throttle valve 5 is increased by setting the increased torque, the magnitude of the pumping loss does not substantially decrease and is substantially constant.

Next, with reference to FIG. 12, another example of the operation of the vehicle control device will be described.
FIG. 12 is a time chart showing an example of the operation of the vehicle control device of the present embodiment, in order from the top, steering angle, steering angular velocity, final target torque, actually generated torque, pumping loss, throttle valve opening degree, intake air. It shows the amount and ignition timing. In the time chart of FIG. 12, the value of the basic torque is constant, the amount of depression of the accelerator pedal is relatively small, and the opening degree of the throttle valve 5 required to generate the basic torque is less than the predetermined value. The action of (processing of steps S17 → S18 in FIG. 5) is shown.

First, at time t11 in FIG. ₁₂ , when the driver starts steering, the steering angle (absolute value) starts to increase, and when the steering angular velocity becomes equal to or greater than the start threshold value set in step S11 in FIG. 5, vehicle attitude control is performed. Is started. In the example shown in FIG. 12, the opening degree of the throttle valve 5 corresponding to the basic torque is relatively small, and the differential pressure before and after the throttle valve 5 is relatively large. Therefore, the start threshold value of the vehicle attitude control is the time shown in FIG. It is set to Th1 which is larger than the case of the chart. When the steering angular velocity reaches the start threshold Th1 at the time t12 in FIG. ₁₂ , the vehicle attitude control is started, and the opening degree of the throttle valve 5 is increased in order to generate the torque obtained by adding the increased torque to the basic torque. ..

Next, when the steering angular velocity becomes constant at time _t13 , the final target torque obtained by adding the torque obtained by adding the increasing torque to the basic torque also becomes a constant value. As the opening degree of the throttle valve ₅ starts to increase at time t12, the intake air amount and the actual torque generated by the engine ₁₀ also start to increase later, and reach a constant value at time _t14 later than time t13. Become.

As described above, there is a time lag between the increase in the throttle valve 5 opening degree and the increase in the intake air amount. However, in the time chart shown in FIG. 12, since the differential pressure before and after the throttle valve 5 is large, the intake air amount increases more rapidly than in the case of the time chart shown in FIG. 11, and the opening degree of the throttle valve 5 increases and the intake air is sucked. The time lag between increases in air volume is reduced. As the intake air amount increases, the fuel injection amount also increases, and the torque actually generated by the engine 10 also increases. In the time chart of FIG. 12, the throttle valve 5 also increases as compared with the case of FIG. The time lag after the opening of the engine starts to increase becomes smaller.

As described above, in the time chart of FIG. 11, by setting the start threshold value of the vehicle attitude control lower than that of FIG. 12, the time lag from the start of steering by the driver to the actual increase of the torque by the vehicle attitude control is the same. Has succeeded in. That is, the time lag from when the driver starts steering until the torque actually increases due to vehicle attitude control is the time lag when the amount of depression of the accelerator pedal is large and the differential pressure before and after the throttle valve 5 is small (time in FIG. 11). The time lag (time t ₁₁ to t ₁₄ in FIG. 12) when the stepping amount is small and the differential pressure between the front and rear is large can be about the same as t ₁ to t ₅ ).

Further, in the time chart shown in FIG. 12, since the opening degree of the throttle valve 5 is less than a predetermined value, when the vehicle attitude control is started, the process in step S18 of FIG. 5 is executed. As a result, the ignition timing by the spark plug 14 is retarded in accordance with the increase in the intake air amount due to the vehicle attitude control.

Here, in the time chart shown in FIG. 12, since the opening degree of the throttle valve 5 is relatively small, the pumping loss becomes relatively large when the engine 10 is generating the basic torque. From this state, when the opening degree of the throttle valve 5 is increased by the vehicle attitude control, the flow path resistance of the throttle valve 5 is reduced accordingly, and the pumping loss is reduced. Therefore, the net torque generated by the engine 10 also increases due to the decrease in the pumping loss, and the increase causes a torque increase to the extent required for vehicle attitude control.

In addition to this, by increasing the opening degree of the throttle valve 5, the intake air amount and the fuel injection amount increase, so that the torque generated by the combustion of the fuel also increases. In this way, the increase in torque due to the decrease in pumping loss and the increase in torque generated by combustion overlap, resulting in an excessive increase in torque with respect to the basic torque. In order to prevent this, when the vehicle attitude control is executed from the state where the opening degree of the throttle valve 5 is less than a predetermined value, the ignition timing by the spark plug 14 is retarded according to the increase in the intake air amount. As a result, the torque generated by the combustion of the fuel can be reduced, and the excessive torque can be suppressed.

Further, in step S16 of FIG. 5, the increased torque is corrected by using the increased torque correction coefficient shown in FIG. 8 based on the differential pressure before and after the throttle valve 5. Here, in the case of the time chart shown in FIG. 11 and the case of the time chart shown in FIG. 12, since the differential pressure before and after the throttle valve 5 is smaller in FIG. 11, the value of the increased torque correction coefficient becomes larger. Therefore, even when the same additional acceleration is set for the same steering angular velocity, the value of the increased torque becomes larger in the case of FIG. 11 in which the differential pressure before and after the throttle valve 5 is small.

Therefore, when the differential pressure before and after the throttle valve 5 is small, the value of the increased torque is increased to a large value by the correction multiplied by the increased torque correction coefficient. Therefore, in order to realize this, the opening degree of the throttle valve 5 is opened. Increases rapidly. As a result, the time lag of the torque generated by the engine 10 can be further shortened, and the time lag when the differential pressure before and after the throttle valve 5 is large can be approached. Further, there is a predetermined relationship between the differential pressure before and after the throttle valve 5 and the opening degree of the throttle valve 5. Therefore, based on the opening degree of the throttle valve 5, the present invention can be configured so that the value of the increased torque correction coefficient becomes larger when the opening degree is large than when the opening degree is small.

According to the vehicle control device of the embodiment of the present invention, when the differential pressure before and after the throttle valve 5 detected by the pressure sensor 33 which is the intake pressure sensor is small (FIG. 11), the differential pressure is large (FIG. 11). The start threshold Th is set lower than that in FIG. 12). As a result, when the differential pressure around the throttle valve 5 is small, the increased torque is set early (time t ₂ ) after the driver starts steering (time t ₁ in FIG. 11), so that the increased torque is increased. Even if the time lag from the setting to the actual increase in torque becomes long, it is possible to increase the torque at an appropriate time. As a result, the responsiveness and linear feeling of the vehicle 200 to the steering operation can be sufficiently improved.

Further, when the differential pressure before and after the throttle valve 5 is small and the torque increase delay is likely to occur, the start threshold value is lowered (FIG. 6), and the differential pressure before and after the throttle valve 5 is small in order to accelerate the torque increase time. In the case of (FIG. 11) and large (FIG. 12), the timing at which the torque actually increases after the driver starts steering (time t ₁ in FIG. 11 and time t ₁₁ in FIG. 12) (time t ₅ in FIG. 11). , The deviation of the time t ₁₄ ) in FIG. 12 becomes small. As a result, it is possible to suppress variations in the responsiveness of the vehicle 200 and the effect of improving the linear feeling depending on the operating state of the engine 10, and it is possible to make it difficult for the driver to feel a sense of discomfort.

Further, according to the vehicle control device of the present embodiment, when the opening degree of the throttle valve 5 is large, the flow path resistance of the air flowing through the throttle valve 5 becomes small, so that the differential pressure before and after the throttle valve 5 is small. (Fig. 9). In the present embodiment, when the opening degree of the throttle valve 5 is large (FIG. 11), the start threshold value is set low (start threshold value = Th2), so that the torque increases when the front-rear differential pressure of the throttle valve 5 is small. The timing can be advanced, and the torque generated at an appropriate timing can be increased.

Further, according to the vehicle control device of the present embodiment, when the differential pressure before and after the throttle valve 5 is small (FIG. 11), the value of the increased torque is set to be larger than when the differential pressure is large (FIG. 12). (Step S16 in FIG. 5, FIG. 8). As a result, when the differential pressure between the front and rear of the throttle valve 5 is small, a large increase torque can be set by a slight change in steering angular velocity, the torque increase time can be advanced, and the torque increase occurs at an appropriate timing. The torque can be increased.

Further, according to the vehicle control device of the present embodiment, when the opening degree of the throttle valve 5 is large (FIG. 11), the increased torque for the same steering angular velocity is increased as compared with the case where the opening degree is small (FIG. 12). The value is set large (step S16 in FIG. 5, FIG. 8). As a result, when the opening degree of the throttle valve 5 is large, a large increase torque is set by a slight change in the steering angular velocity, the torque increase time can be accelerated, and the torque generated at an appropriate timing can be obtained. Can be increased.

Further, according to the vehicle control device of the present embodiment, the ignition timing of the spark plug 14 is retarded based on the increase in the intake amount due to the setting of the increased torque (steps S18 and 10 in FIG. 5). When the opening degree of the throttle valve 5 is increased to reduce the pumping loss (FIG. 12), the torque generated by the combustion of fuel can be reduced. This makes it possible to suppress an excessive increase in torque.

Although the preferred embodiment of the present invention has been described above, various modifications can be made to the above-described embodiment. In particular, in the above-described embodiment, the pressure difference between the front and rear of the throttle valve 5 is detected based on the detection signals of the pressure sensor 33 and the atmospheric pressure sensor 36, but the intake pressure on the downstream side of the throttle valve 5 is measured. It is also possible to obtain the pressure difference only from the detection signal of the pressure sensor 33.

Further, there is a predetermined relationship between the pressure difference between the front and rear of the throttle valve 5 and the opening degree of the throttle valve 5. Therefore, the present invention is configured so that the start threshold value of vehicle attitude control is set based on the opening degree of the throttle valve 5, and when the opening degree is large, the start threshold value is set lower than when the opening degree is small. You can also do it.

Further, as shown by an imaginary line in FIG. 2, the present invention can be applied to an engine system 100 provided with a supercharger 42. In this case, the supercharging pressure by the supercharger 42 and the pressure sensor 33 can be applied. The start threshold value can be set based on the pressure difference from the pressure on the downstream side of the throttle valve 5 detected by. In this case, the present invention can be configured so that when the differential pressure between the boost pressure and the pressure on the downstream side of the throttle valve 5 is small, the start threshold value is set lower than when the differential pressure is large. ..

1 Intake passage 5 Throttle valve (intake throttle valve)
10 Engine 13 Fuel injection valve 14 Ignition plug 15 Piston 16 Crankshaft 25 Exhaust passage 30 Accelerator opening sensor 31 Airflow sensor 32 Throttle opening sensor 33 Pressure sensor (intake pressure sensor)
36 Atmospheric pressure sensor 39 Vehicle speed sensor 40 Steering angle sensor (steering angle related value detection sensor)
42 Supercharger 50 PCM (control)
100 Engine system 200 Vehicle 202a Front wheel 202b Rear wheel 203 Suspension 204a Transmission 204b Propeller shaft 204c Differential gear 206 Steering wheel 207 Steering device

Claims (7)

It is a control device for vehicles in which the rear wheels are driven.
A steering device for steering the front wheels of the vehicle and
The engine that drives the rear wheels of the above vehicle and
The intake throttle valve provided in the intake passage of this engine and
An intake pressure sensor provided on the downstream side of the intake passage from the intake throttle valve,
Fuel injection valve and
A steering angle-related value detection sensor that detects a steering angle-related value related to the steering angle of the steering device,
A driving state sensor that detects the driving state of the vehicle and
It has a controller that controls the engine and
The above controller
Set the basic torque based on the operating condition detected by the above operating condition sensor, and set the basic torque.
When the steering angle-related value detected by the steering angle-related value detection sensor becomes equal to or higher than a predetermined start threshold value, an increased torque is set based on the steering angle-related value.
The engine is configured to control the intake throttle valve and the fuel injection valve so as to generate a torque obtained by adding the increased torque to the basic torque.
The controller is configured to set the start threshold value lower when the differential pressure before and after the intake throttle valve detected by the intake pressure sensor is small than when the differential pressure is large. A characteristic vehicle control device. The vehicle control device according to claim 1, wherein the controller is configured to set the start threshold value lower when the opening degree of the intake throttle valve is large than when the opening degree is small. The controller is configured to set a larger value of increased torque with respect to the same steering angle-related value when the differential pressure before and after the intake throttle valve is small than when the differential pressure is large. Item 2. The vehicle control device according to item 1 or 2. Claim 1 is configured such that when the opening degree of the intake throttle valve is large, the value of the increased torque with respect to the same steering angle-related value is set larger than when the opening degree is small. The vehicle control device according to any one of items 3 to 3. The engine is provided with a supercharger, and the controller is used when the difference pressure between the supercharging pressure by the supercharger and the pressure on the downstream side of the intake throttle valve detected by the intake pressure sensor is small. The vehicle control device according to any one of claims 1 to 4, which is configured to set the start threshold lower than when the differential pressure is large. Any of claims 1 to 5, wherein the engine includes a spark plug, and the controller is configured to retard the ignition timing of the spark plug based on an increment of intake air by setting an increased torque. The vehicle control device according to item 1. It is a control device for vehicles in which the rear wheels are driven.
A steering device for steering the front wheels of the vehicle and
The engine that drives the rear wheels of the above vehicle and
The intake throttle valve provided in the intake passage of this engine and
A throttle opening sensor that detects the opening of the intake throttle valve and
Fuel injection valve and
A steering angle-related value detection sensor that detects a steering angle-related value related to the steering angle of the steering device,
A driving state sensor that detects the driving state of the vehicle and
It has a controller that controls the engine and
The above controller
Set the basic torque based on the operating condition detected by the above operating condition sensor, and set the basic torque.
When the steering angle-related value detected by the steering angle-related value detection sensor becomes equal to or higher than a predetermined start threshold value, an increased torque is set based on the steering angle-related value.
The engine is configured to control the intake throttle valve and the fuel injection valve so as to generate a torque obtained by adding the increased torque to the basic torque.
The controller is characterized in that when the opening degree of the intake throttle valve detected by the throttle opening degree sensor is large, the start threshold value is set lower than when the opening degree is small. Vehicle control device.

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