JPH0151382B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a braking force holding device for a vehicle that prevents the return movement of the brake pedal without manual effort to maintain the braking force after the vehicle is stopped by depressing the brake pedal.

A conventional device of this kind is one described in Japanese Patent Publication No. 54-7100, but in this conventional device, an actuator is used to prevent the return movement of the brake pedal that controls the service brake system of the vehicle. The operation command signal is transmitted by the control unit when the zero vehicle speed state continues for a set time (approximately 2 seconds) based on the rotation of the vehicle's drive system. This is to distinguish between locking the wheels while the vehicle is decelerating and actually stopping the vehicle. However, since the braking force will not be maintained unless the brake pedal is depressed for the above set time after the vehicle has stopped, operating the brake pedal is cumbersome. There was a strange flaw.

SUMMARY OF THE INVENTION An object of the present invention is to improve the control unit and eliminate the above-mentioned drawbacks.

In the present invention, the control unit includes a vehicle speed detector that detects the vehicle speed based on the rotation of the vehicle's drive system, a variable resistor that is linked to the brake pedal and generates a voltage signal according to the depression of the brake pedal, and a vehicle speed detector that detects the vehicle speed based on the rotation of the vehicle drive system. It detects whether the signal from the detector is lower than the set vehicle speed, and calculates the brake pedal depression acceleration from the rate of change of the voltage signal from the variable resistor over a predetermined time, and determines whether the brake pedal depression acceleration is equal to the set acceleration. and a computer that detects whether the vehicle speed is above the set speed and sends an operation command signal when the signal from the vehicle speed detector is below the set vehicle speed and the brake pedal depression acceleration is greater than or equal to the set brake pedal depression acceleration regardless of the amount of brake pedal depression. composition.

The set vehicle speed is set to a value below several km/h (approximately 5 km/h) at which there is no safety problem even if the wheels lock up, and the set pedal acceleration is set to a value larger than the normal range. Therefore, when the driver wants to maintain braking force, it is sufficient for the driver to consciously press the brake pedal with an acceleration equal to or higher than the set depression acceleration when the vehicle speed is below the set speed, regardless of the amount of depression of the brake pedal. The hassle of operation is reduced compared to conventional methods. In addition, with conventional devices, when the vehicle speed detection function of the control unit is impaired and the vehicle is erroneously judged to have been connected for a set period of time even though the vehicle is running at zero speed, an activation command signal is automatically sent to the activation unit. However, with the present invention, there is no such concern. In order to solve the above-mentioned conventional problems, it may be possible to activate the brake pedal when the amount of depression exceeds the set amount of depression, but this is done in order to ensure controllability of the braking force during normal braking. A necessary condition is that the set amount of depression be greater than the commonly used range. Therefore, it is possible to press the brake pedal further than would normally be required to stop the vehicle, but this means that the hydraulic pressure in the path from the master cylinder to the actuator such as the wheel cylinder of the wheel is higher than the normal range. This value is maintained at this value while the vehicle is stopped, and a large load is placed on the seal member disposed within the route, reducing the durability of the seal member. This problem,
The problem can be solved by setting the control unit to issue an operation command signal when the vehicle speed is below the set value and the amount of brake pedal depression exceeds the set amount of depression, so that the amount of depression of the brake pedal is within the set amount of depression. However, in this case, if the vehicle speed detector or the like fails, an operation command signal is always transmitted during normal braking, which deteriorates the controllability of the braking force. However, in the present invention, the acceleration of the brake pedal depression is used as a basis for determining the activation command signal, so the brake pedal operation to maintain the braking force is independent of the amount of depression of the brake pedal, that is, the brake fluid pressure. This can be done by the driver.

Hereinafter, one embodiment of the present invention will be described based on the drawings. In Figures 1 to 3, reference numeral 1 denotes a brake pedal, which is rotatably supported on a bracket 2 fixed to the vehicle body with a pin 3 as a fulcrum.When the pedal 1 is depressed (rotated clockwise in Figure 1) ) and the push rod 4 push the piston of the brake master cylinder M of the service brake system, and a braking force is generated by the operation of the service brake system.

Reference numeral 5 denotes an actuating part for selectively blocking the return movement of the brake pedal 1. A rack gear 6 is fixed to the brake pedal 1 with a bolt 7, and teeth 8 are provided on the lower edge of the central window. A pinion gear 9 is engaged with the teeth 8. The pinion gear 9
is provided so as to rotate integrally on a shaft 12 that rotatably passes through a bracket 11 fixed to the bracket 2 with a bolt 10. The rotating member 13 on the opposite side of the bracket 11 from the pinion gear 9 side is also connected to the shaft 1.
2 so that they rotate together. A spring member 14 is disposed on the outer peripheral side of the rotating member 13. The spring member 14 is connected to the rotating member 13
Coil portion 14a to be frictionally engaged with peripheral surface 13a of
It has one end 14b fixed on the bracket 11 by a fixing plate 15 welded to the bracket 11, and the other end 14c free. In the free state of the spring member 14, the inner diameter of the coil portion 14a is slightly larger than the outer diameter of the circumferential surface 13a of the rotating member 13. A retainer 16 is provided on the shaft 12 to prevent the spring member 13 from coming off.
17 and 18 are washers.

The coil portion 14a of the spring member 14 has the other end 1
4c is pushed toward the upper left in FIG. Under this state of frictional engagement, if the rotating member 13 attempts to rotate counterclockwise in FIG. Coil part 1
4a is wound around the rotating member 13, so that the rotating member 1
3 is prevented from rotating. On the contrary, when the rotating member 13 tries to rotate clockwise in FIG. 14a is not wound around the rotating member 13, and the rotating member 13 can rotate.

Reference numeral 19 denotes an actuator for pushing the other end 14c of the spring member 14, which includes an electric motor 20 held by the bracket 11 and a sliding member 22 with a rack gear that is slidably supported by a bracket 21 fixed to the bracket 11. It becomes more. The rack gear 22a of this sliding member 22 meshes with a pinion gear 23 fixed to the rotating shaft of the electric motor 20,
The forked head 22b of the sliding member 22 locks the bent portion 14d of the other end 14c of the spring member 14. A return spring 25 is interposed between the retainer 24 attached to the sliding member 22 and the bracket 21, and urges the sliding member 22 downward and to the right in FIG.

The control unit 26 that energizes the electric motor 20, that is, provides an operation command signal to the actuating unit 5, is a switch 2 that opens and closes the drive circuit of the electric motor 20, as shown in FIG.
7, a vehicle speed detector 29 that sends a signal to the computer 28, an accelerator pedal depression switch 30, and a variable resistor 31 that is linked to the brake pedal 1. As is well known, the vehicle speed detector 29 sends a vehicle speed signal based on the rotation of the vehicle's drive system, and can also be used as a vehicle speedometer detector. As is well known, the accelerator pedal depression responsive switch 30 is switched from closed to open when the accelerator pedal is depressed. The variable resistor 31 is arranged on the bracket 11 side of the rotating member 13 as shown in the first and second figures, and consists of a resistor 31a fixed to the bracket 11 and a sliding body 31b fixed to the rotating member 13. A constant voltage is applied to both ends of the resistor 31a, and the voltage of the sliding body 31b is sent to the computer 28 as a signal.
granted to. The computer 28 determines whether or not the vehicle speed is lower than the set vehicle speed based on the signal from the first vehicle speed detector 29, and if the vehicle speed is lower than the set vehicle speed, the computer 28 detects the accelerator pedal based on the signal from the accelerator pedal depression response switch 30. Determine whether or not it has been released. Then, under the condition that the vehicle speed is below the set vehicle speed and the accelerator pedal is released, the computer 28 determines the depression speed of the brake pedal 1 based on the voltage signal from the variable resistor 31 and the rate of change in the voltage signal over a predetermined time. , and further differentiates the speed with respect to time to calculate the depression acceleration. Then, the computer 28 determines whether the calculated depression acceleration is equal to or greater than the set depression acceleration regardless of the amount of depression of the brake pedal, and if it is greater than or equal to the set depression acceleration, the odd-numbered set depression acceleration occurs. The switch 27 is closed in response to this, and the switch 27 is opened in response to the occurrence of the even-numbered set acceleration.
In FIG. 4, 32 is a battery, and 33 is an ignition switch.

Next, the action will be explained.

When the vehicle is running at a higher speed than the set vehicle speed, at least the vehicle speed switch 30 is open, so the electric motor 20 is not energized, and the sliding member 22 is moved toward the lower right in FIG. 1 by the return spring 25. The spring member 14 is in a free state and its coil portion 14a is separated from the circumferential surface 13a of the rotating member 13, and the rotating member 13 is rotated clockwise and counterclockwise in FIG. It can be rotated freely in any direction. Therefore, after the brake pedal 1 is once depressed, if the brake pedal 1 is released before the vehicle speed decreases to the set vehicle speed, the brake pedal 1 is returned to its return position by a return spring (not shown).

When the brake pedal 1 is depressed when the vehicle speed is higher than the set vehicle speed, the brake pedal 1 rotates clockwise around the pin 3 as shown in Fig. 1, and the master cylinder M is operated by the push rod 4 to generate braking force. and the vehicle speed decreases. Since the accelerator pedal is released when the vehicle is braked, the accelerator pedal switch 29 is closed. Therefore, when the vehicle speed falls below the set vehicle speed, if the driver depresses the brake pedal 1 at a speed greater than or equal to the set pedal acceleration regardless of the amount of depression of the brake pedal in order to maintain the braking force, the computer 28 will activate the switch. 27 is closed and the electric motor 20 is energized,
As the electric motor 20 rotates the pinion gear 23 counterclockwise in FIG. 3, the sliding member 22 slides toward the upper left in FIG.
c and press the coil part 14 of the spring member 14.
a reduces in diameter and frictionally engages with the circumferential surface 13a of the rotating member 13, and the rotating member 13 becomes unable to rotate counterclockwise in FIG. In order for the brake pedal 1 to rotate counterclockwise in Fig. 1 and return to its original position, the rotating member 1 is
3 is required to rotate counterclockwise in FIG. 1, the return movement of the brake pedal 1 is ultimately prevented, and the braking force generated by the operation of the service brake system is maintained.

When the driver presses the accelerator pedal to start,
The accelerator pedal depression switch 29 is opened, the computer 28 opens the switch 27, and the electricity to the electric motor 20 is stopped. As a result, the sliding member 22 is returned to the return position by the return spring 25 and the spring member 14, the coil portion 14a of the spring member 14 expands in diameter and separates from the circumferential surface 13a of the rotating member 13, and the rotating member 13 is moved to the first position.
Since the brake pedal 1 can be rotated counterclockwise in the figure, the brake pedal 1 returns to its original position and the braking force is eliminated.

The above-mentioned braking force release can also be performed by re-depressing the brake pedal 1 at a predetermined depressing acceleration or more, regardless of the amount of depressing.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an operating part of an embodiment of the present invention;
Figure 2 is a sectional view taken along the - line in Figure 1, and Figure 3 is a cross-sectional view of Figure 1.
The directional view in the figure, FIG. 4 is a diagram showing the control section. 1...brake pedal, 5...actuating part, 20...
...Electric motor, 26...Control unit, 27...Switch,
28...computer, 29...vehicle speed detector, 3
1...Variable resistor.

Claims (1)

[Claims] 1. An actuator that prevents the return movement of the brake pedal that controls the vehicle's service brake system in response to an operation command signal, a vehicle speed detector that detects the vehicle speed based on the rotation of the vehicle's drive system, and a vehicle speed detector that is linked to the brake pedal. , a variable resistor that generates a voltage signal in response to depression of the brake pedal, a variable resistor that detects whether the signal from the vehicle speed detector is below a set vehicle speed, and a rate of change of the voltage signal from the variable resistor over a predetermined time. The acceleration of the brake pedal is calculated from the acceleration of the brake pedal, and it is detected whether the acceleration of the brake pedal is equal to or higher than the set acceleration. A braking force holding device for a vehicle, comprising a control unit comprising a computer that transmits an operation command signal when the pedal depression acceleration is equal to or higher than a set pedal acceleration, regardless of the amount.