JP2006083741A - Vehicle braking control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle braking control system surely inhibiting swing back on stopping at a low cost. <P>SOLUTION: When vehicle speed V slows down to the extent that control should be performed (YES at step S2), a deceleration D is calculated (step S3). The deceleration D is obtained from brake leg-power detected by a brake leg-power sensor and the vehicle speed V or by differentiating the vehicle speed V. If the deceleration D is larger than a predetermined judgment value Da (YES at step S4), necessary torque T for lowering the deceleration D below the judgment value Da is calculated (step S5), a necessary throttle opening ATH for obtaining the torque T is calculated (step S6) and a throttle motor is operated to have the necessary throttle opening ATH. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle braking control device that controls braking of a vehicle.

  When braking a vehicle with a vehicle body mounted on a wheel via an elastic suspension system like an automobile, a phenomenon that the vehicle body swings back and forth after stopping unless it is carefully braked, the so-called rebound occurs. To do. FIG. 7 is a diagram for explaining the occurrence of the swingback. Immediately before stopping, the suspension system on the front side of the vehicle body is compressed by the inertial force and the suspension system on the rear side of the vehicle body is extended. When it disappears, the suspension system on the front side of the vehicle body is extended by the reaction force and the suspension system on the rear side of the vehicle body is compressed. This occurs in a vibrational manner until it dampens, causing a shakeback.

  Therefore, an apparatus for preventing the occurrence of the swing back has been developed. For example, there is an apparatus described in Patent Document 1. This device discloses that the target acceleration / deceleration is calculated and the brake device is controlled so as to obtain the calculated acceleration / deceleration.

  Since the above technology controls the brake device, it is necessary to precisely control the brake device. Since the brake device is attached to each tire, four brake control devices are usually required accordingly, and the cost is high. In addition, the control is complicated because there is a risk of meandering unless the four brake control devices are comprehensively controlled.

JP 2000-43697 A

  In view of the above problems, an object of the present invention is to provide a vehicle braking control device capable of preventing the occurrence of rocking back at a stop by simple control at low cost.

According to invention of Claim 1, it is a vehicle braking control apparatus which controls braking of a vehicle,
The vehicle is mounted on the vehicle upper structure via a suspension system having elasticity with respect to the vehicle lower structure including the wheels, includes a drive source, and travels by transmitting the driving force generated by the drive source to the wheels. In what has been
Deceleration calculation means for calculating deceleration during vehicle braking;
Driving force increasing means for increasing the driving force of the driving source so that the calculated deceleration is greater than the deceleration at which the swingback occurs after the stop, so that the deceleration does not occur after the stop; A vehicle braking control device is provided.
In the vehicle braking control device configured as described above, when the deceleration is larger than the deceleration at which the swingback occurs after the stop, the driving force of the drive source is set so that the deceleration does not occur after the stop. It is increased and the occurrence of swing back is prevented.

According to the second aspect of the present invention, the driving source is an internal combustion engine that obtains driving force by combusting an air-fuel mixture obtained by mixing fuel at a predetermined ratio with intake air that is metered by the intake throttle valve, and the driving force increasing means is the intake air. Throttle valve opening increasing means for increasing the opening of the throttle valve is provided.
In the vehicle braking control apparatus configured as described above, the driving force is increased so that the opening degree of the intake throttle valve of the internal combustion engine is increased and the deceleration is reduced so that no swinging occurs after the stop.

  According to the invention of claim 3, control is executed at a speed equal to or lower than a predetermined speed.

  The invention described in each claim is a vehicle braking control device that controls braking of a vehicle, and the vehicle upper structure is mounted via a suspension system in which the vehicle has elasticity with respect to the vehicle lower structure including wheels. The vehicle is provided with a drive source and travels by transmitting the driving force generated by the drive source to the wheels, and includes a deceleration calculation means for calculating a deceleration during vehicle braking, and a calculated deceleration A driving force increasing means for increasing the driving force of the driving source so that the speed is a deceleration that does not cause the swingback after the stop when the speed is larger than the deceleration that causes the swingback after the stop. Yes. As a result, if the deceleration is greater than the deceleration at which the swingback occurs after the stop, the driving force of the drive source is increased so that the swingback does not occur after the stop and the occurrence of the swingback occurs. Is prevented.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a diagram for explaining the hardware configuration of the present invention. The vehicle 1 includes a vehicle body 4 mounted on front wheels 2f and rear wheels 2r via elastic front suspensions 3f and rear suspensions 3r. An internal combustion engine 10 is mounted on the vehicle body 4. The output of the internal combustion engine 10 is transmitted to the rear wheel 2r via the transmission 20, the propeller shaft 21, and the differential gear 22.

  Air introduced through the intake pipe 11 is mixed with fuel injected from the fuel injection valve 15 and supplied to each cylinder (not shown) of the internal combustion engine 10. The fuel injection amount is determined according to the intake air amount. The intake pipe 11 is provided with a throttle valve 12 for adjusting the intake air amount. The throttle valve 12 is driven by a throttle motor 13 to change the opening, and the opening is detected by a throttle opening sensor 14.

  An accelerator pedal 30 is provided with an accelerator opening sensor 31 that generates a signal current corresponding to the amount of depression when the accelerator pedal 30 is depressed. The output of the accelerator opening sensor 31 is an ECU (electronic control unit). 100 is sent to the throttle motor 13 from the ECU 100, and the throttle valve 12 is opened according to the depression amount of the accelerator pedal 30. Reference numeral 32 denotes a brake pedal, which is provided with a brake pedal force sensor 33 that sends a signal current corresponding to the pedal force of the brake pedal 32 to the ECU 100. The transmission 20 is provided with a vehicle speed sensor 23 that sends a signal current corresponding to the vehicle speed to the ECU 100.

The ECU 100 is formed by connecting an input port 101, an output port 102, a CPU 103, a ROM 104, a RAM 105, and the like with a common bus.
The ECU 100 receives a signal detected by each sensor related to the present invention, and sends a control signal for performing control related to the present invention to each actuator. In addition, sensors and actuators for performing control not related to the present invention are connected.

  Hereinafter, the control of the embodiment of the present invention that is configured as described above will be described. The idea is that the deceleration is calculated below a predetermined speed, and the calculated source speed deteriorates drivability. In the case of the level, the intake air amount is increased to increase the torque to prevent the drivability from deteriorating.

FIG. 3 is a flowchart of the embodiment of the present invention executed based on the above.
In step S1, parameters such as the vehicle speed and the throttle opening are read.
In step S2, whether or not the vehicle speed V is low enough to be controlled is determined by comparing with a predetermined determination value Va. If a positive determination is made in step S2, the process proceeds to step S3. If a negative determination is made, step S2 is repeated until a positive determination is made.

In step S3, the deceleration D is calculated. This is obtained from the brake pedal force detected by the brake pedal force sensor 33 and the vehicle speed V, but can also be determined by differentiating the vehicle speed V.
In step S4, it is determined whether or not the deceleration D stopped in step S is larger than a predetermined determination value Da. If an affirmative determination is made in step S4, the process proceeds to step S5. If a negative determination is made, the control according to the present invention is unnecessary, and the process ends.

  In step S5, the torque T required to make the deceleration D equal to or less than the determination value Da is calculated from the map of FIG. In step S6, the throttle opening ATH required to obtain the torque T calculated in step S5 is calculated from the map of FIG. Then, in step S7, the throttle motor 13 is operated so that the throttle opening ATH calculated in step S6 is obtained, and the process ends.

  FIG. 5 is a time chart showing the effect of the above control. The broken line indicates the acceleration of the vehicle lower structure including the tires 2f and 2r, and has a negative value because braking is in progress. The solid line shows the relative acceleration of the vehicle upper structure composed of the vehicle body 4 composed of the vehicle suspension 4 attached to the vehicle lower structure via the suspension system front suspension 3f and rear suspension 3r. By controlling as described above, the relative acceleration of the upper part of the vehicle body to the lower part of the vehicle body after the vehicle speed V becomes zero shows a gentle change as shown in the figure.

  On the other hand, FIG. 6 shows a similar time chart when the above control is not performed. As shown in the figure, the relative acceleration of the vehicle upper structure to the vehicle lower structure after the vehicle speed V becomes zero is As shown in the figure, it changes greatly and so-called rocking occurs.

  The present invention can be applied to a vehicle including a braking device. In particular, the vehicle is equipped with a vehicle upper structure via a suspension system having elasticity with respect to the vehicle lower structure including the wheels, and includes a drive source and travels by transmitting the driving force generated by the drive source to the wheels. In such a configuration, it is possible to prevent occurrence of rocking back when stopped.

It is a figure explaining the hardware constitutions of embodiment of this invention. It is a flowchart of control of an embodiment of the invention. It is a figure which shows a torque required in order not to generate rocking back. FIG. 4 is a diagram showing a throttle opening for generating the torque of FIG. 3. It is a time chart which shows the behavior of the vehicle body at the time of performing control of the present invention. It is a time chart which shows the behavior of the vehicle body when not performing control of the present invention. It is a figure explaining generation | occurrence | production of shaking back.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 2f Front wheel 2r Rear wheel 3f Front suspension 3r Rear suspension 4 Car body 10 Internal combustion engine 11 Intake pipe 12 Throttle valve 13 Throttle motor 14 Throttle opening sensor 20 Transmission 23 Vehicle speed sensor 30 Accelerator pedal 31 Accelerator opening sensor 32 Brake pedal 33 Brake pedal force sensor 100 ECU

Claims (3)

A vehicle braking control device for controlling braking of a vehicle,
The vehicle is mounted on the vehicle upper structure via a suspension system having elasticity with respect to the vehicle lower structure including the wheels, includes a drive source, and travels by transmitting the driving force generated by the drive source to the wheels. In what has been
Deceleration calculation means for calculating deceleration during vehicle braking;
Driving force increasing means for increasing the driving force of the driving source so that the calculated deceleration is greater than the deceleration at which the swingback occurs after the stop, so that the deceleration does not occur after the stop; Comprising
A vehicle braking control device characterized by the above. An internal combustion engine that obtains driving force by combusting an air-fuel mixture in which fuel is mixed at a predetermined ratio with intake air that is metered by an intake throttle valve as a driving source,
The driving force increasing means is throttle valve opening increasing means for increasing the opening of the intake throttle valve,
The vehicle braking control device according to claim 1.   The vehicle braking control device according to claim 1, wherein the control is executed at a speed equal to or lower than a predetermined speed.

Images