JPH0848222A - Stop maintenance device for vehicle - Google Patents

Abstract

PURPOSE:To securely maintain the stopping state of a vehicle during vehicle stop by a control portion operating a braking power increase means under the conditions of vehicle stop being detected and parking brake operation being detected. CONSTITUTION:At each vehicle wheel of a vehicle, a vehicle movement detecting means 2 to detect the movement state of the vehicle is provided, and the output of the vehicle movement detecting means 2 is inputted into a control portion 4. A parking brake sensor 12 to detect the operation state of a parking brake is connected to the control portion 4, and this parking brake sensor 12 is made up of a switch to detect the operation of a parking lever, and in a case in which the vehicle is stopped and the parking brake is operated, the control portion 4 operates a brake power increase means 3 forcedly under the conditions of the vehicle movement detecting means 2 detecting vehicle stop and the parking brake sensor 12 detecting the operation of the parking brake.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle braking system,
In particular, it relates to a system for maintaining a stopped state when a vehicle stops.

[0002]

2. Description of the Related Art Conventionally, there have been provided various stop-maintaining devices for a vehicle which automatically apply a brake at the same time as a vehicle stops on a slope to prevent the vehicle from moving backward (forward).

Further, when the vehicle is started to move due to leakage of brake fluid pressure or loading of new luggage on the vehicle while the parking brake is applied to the known stop / maintenance device, the braking force is automatically increased. It is possible to think of a device that includes means to reliably maintain the stopped state of the vehicle.

[0004]

However, in the above-mentioned automatic braking device, the braking force increasing means is operated when the control unit judges the movement of the vehicle by the signal from the speed sensor, but it cannot be detected by the speed sensor. When the vehicle moves at an extremely low speed or when the speed sensor fails, the braking force increasing means becomes inoperable.

On the other hand, in order to improve the durability of the braking force increasing means, it is also desired to reduce the operating frequency of the braking force increasing means. The present invention has been made in view of the above matters, and a technical object thereof is to provide a device that reliably maintains a stopped state of a vehicle that is stopped.

Another object of the present invention is to provide a device for reducing the frequency of operation of the braking force increasing means of the device for reliably maintaining the stopped state of the stopped vehicle. Moreover, it is a technical subject to improve the durability of a device that reliably maintains a stopped state of a stopped vehicle.

Further, it is a technical object to provide a device for surely maintaining the stopped state of the vehicle even when the vehicle is stopped on a steep slope.

[0008]

In order to solve the above technical problems, the present invention has the following constitution. That is, a parking brake sensor that detects an operating state of a parking brake, a vehicle movement detecting unit that detects a moving state of a vehicle, a braking force increasing unit that increases a braking force, a parking brake sensor, a vehicle movement detecting unit, and a brake. And a control unit connected to the force increasing means.

The control unit is configured to operate the braking force increasing means on the condition that the stop of the vehicle is detected and the operation of the parking brake is detected.

The parking brake sensor may be configured to include a pulling force sensor for detecting a pulling force of a wire connecting the parking lever of the parking brake and the brake operating portion. In this case, the control unit operates the braking force increasing means when the detection value of the pulling force sensor is less than the first set value, and
When the detection value of the pulling force sensor is equal to or larger than the first set value, the braking force increasing means can be controlled to be in the inoperative state. The pulling force sensor may be, for example, a resistance wire strain gauge, a piezoelectric element, a pressure switch, or the like. Further, the parking brake sensor may be a mechanical switch or a non-contact switch such as a photo interrupter.

It is also possible to provide an inclination sensor which detects an inclination state of the road surface and outputs a signal to the control section. In this case, the control unit may be configured to operate the braking force increasing means when the gradient detection value from the inclination sensor is equal to or greater than the second set value. As the tilt sensor, a tilt sensor using a mercury switch, a G sensor using a Hall element, or the like can be exemplified.

Further, the control section may activate the braking force increasing means only when it is determined that the driver is not performing a driving operation. In this case, an engine rotation sensor connected to the control unit for detecting the operating state of the engine, a foot brake sensor for detecting the operating state of the foot brake, a clutch sensor for detecting the operating state of the clutch, and a gear position in neutral. It is desirable to include a gear position sensor that detects whether or not the position is set. The control unit detects that the vehicle is stopped, that the parking brake is activated, that the engine is rotating and the gear position is in the neutral position, or that the engine is stopped. It is determined that the driver is not performing a driving operation on the condition that the non-operation of the foot brake and the non-operation of the clutch are detected, and the braking force increasing means is operated. Can be configured to.

Here, the control unit is a central processing unit (CP).
U), a read / write memory (RAM), a read-only memory (ROM), an input / output device (I / O), and a bus connecting these may be provided.

The braking force increasing means can be composed of a pressurizing portion and an electromagnetic valve interposed between the pressurizing portion and the brake mechanism. In this case, the pressurizing unit can be a pressure tank or the like that can be maintained in a pressurized state in advance by an electric pump or the like, and the pressure can be configured to be supplied to the brake mechanism by opening and closing an electromagnetic valve. The braking force increasing means can use a traction control device for preventing acceleration slip of the wheels.

The braking force increasing means includes a motor that rotates in the normal direction and a reverse direction, a valve element that moves forward by the normal rotation of the motor and returns by reverse rotation, and communicates with the brake mechanism and moves the valve element forward. It is also possible to provide a pressure chamber whose chamber volume is reduced by movement.

Further, the braking force increasing means may be a device for forcibly pulling the wire of the parking brake. As the vehicle movement detecting means, for example, a speed sensor can be used.

The engine rotation sensor can be exemplified by a sensor that detects the output voltage of an alternator (alternating current generator) that generates electric power as the engine rotates. The foot brake sensor may be a sensor that detects an operating state of a brake pedal, and may be a brake pedal switch.

Further, the clutch sensor can be a sensor for detecting the operating state of the clutch pedal, and a clutch pedal switch can be exemplified. The gear position sensor is a sensor that detects the gear position of the transmission, and may be a sensor that outputs a signal when the gear position is in the neutral position.

In addition to the above components, stop maintaining means may be added. The stop maintaining means may be configured to detect the stop state of the vehicle and maintain the brake pressure in the brake mechanism to maintain the stop state of the vehicle. Here, the brake mechanism can be configured by a wheel cylinder or a brake caliper. The brake mechanism can be configured to operate by hydraulic pressure, pneumatic pressure, or the like.

[0020]

When the signal indicating that the parking brake is operating is output from the parking brake sensor while the signal indicating that the vehicle is stopped is being output from the vehicle movement detecting means, the control section causes the braking force increasing means. To increase the braking force of the vehicle.

The control unit operates the braking force increasing means when the detected value of the parking brake sensor (pulling force sensor) is less than the first set value, and
When the detected value of the pulling force sensor is equal to or larger than the first set value, the braking force increasing means is controlled to the inoperative state.

In the case where the inclination sensor for detecting the inclination state of the road surface is provided, the control section forcibly activates the braking force increasing means when the inclination detection value from the inclination sensor is not less than the second set value. Can be activated.

The control section operates the braking force increasing means only when it is determined that the driver is not performing a driving operation. In this case, the control unit detects the stop of the vehicle, the operation of the parking brake, the engine is rotating and the gear position is at the neutral position, or the stop of the engine is detected. If the condition that the driver's foot brake is not operated and the clutch is not operated is detected, it is determined that the driver is not performing a driving operation, and the braking force is increased. The means can be forcefully activated.

[0024]

EXAMPLES Examples of the present invention will be described. <First Embodiment> A first embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, the vehicular stop / maintenance device of this embodiment has a master cylinder 32 that pushes out brake pressure fluid when the brake pedal 30 is depressed. Further, it has a wheel cylinder 20 that brakes the wheels by hydraulic pressure from the master cylinder 32.

Master cylinder 32 and wheel cylinder 2
An electromagnetic valve 35 is provided on the liquid passage 10 between the solenoid valve 0 and the liquid valve. This solenoid valve 35 has a solenoid coil and a movable iron core that opens and closes the valve, and in response to an instruction signal from the control unit 4, the valve is opened and closed to hold the brake pressure liquid in the wheel cylinder 20. It is to be released.

That is, when the vehicle is stopped by depressing the brake pedal 30, the brake fluid pressure is maintained and the braking force is maintained even if the foot is released from the brake pedal 30.
Further, the solenoid valve 35 is provided with a check valve to allow the transmission of pressure from the master cylinder 32 side to the wheel cylinder 20 side. Therefore, when the driver repressurizes the brake pedal, the pressure is supplied from the master cylinder 32 side to the wheel cylinder 20 side through the check valve.

A display lamp 37 is connected to the control unit 4, and when the solenoid valve 35 is operated, the lamp is turned on to let the driver recognize that the automatic brake is in operation. ing.

Vehicle wheels are provided with vehicle movement detecting means 2 for detecting the movement state of the vehicle. This can also be used as a speedometer sensor. The output of the vehicle movement detecting means 2 is input to the control section 4. The control unit 4 is composed of a microcomputer (ECU), and is composed of a memory, I / O, etc. (not shown).

On the other hand, a braking force increasing means 3 capable of increasing the hydraulic pressure in the liquid passage 10 is connected to the liquid passage 10. The braking force increasing means 3 is connected to the control section 4 and pumps the brake fluid to the fluid passage 10 according to a signal from the control section 4 to increase the fluid pressure of the wheel cylinder 20.

That is, the braking force increasing means 3 is
As shown in FIG. 2, a spool valve type valve body 65 is slidably provided inside an inner cylinder of the cylinder body 60. This valve body 65 is used for the master cylinder 32.
It has a peripheral groove 66 facing the communication port 62 communicating with the side, and a flow path 67 opening from the peripheral groove 66 to the tip surface 65a. The tip surface 65a faces the pressure chamber 70 communicating with the wheel cylinder 20. Further, the rear end of the valve body 65 is linked to the output screw shaft 82 of the motor 80 screwed through the screw hole 68, and the rotation preventing shaft 61 and the axial hole 6 provided in the cylinder body 60.
The rotation around the axis is restrained by the fitting of the shaft 9.

When the motor 80 is rotated in the reverse direction, the output screw shaft 82 idles at the rightmost position (final return position) of the valve body 65, so that the motor 80 is not overloaded. Further, the control unit 4 can determine the operating state of the braking force increasing means 3 (whether or not automatic pressurization is being performed).

Further, the control section 4 has a parking brake sensor 1 for detecting the operating state of the parking brake.
2 is connected. This parking brake sensor 1
A piezoelectric element 2 is adapted to detect the pulling force of the wire connecting the parking lever of the parking brake and the brake operating portion. The parking brake sensor may be composed of a switch that detects the operation of the parking lever.

Further, a brake sensor 11 for detecting the operating state of the foot brake is connected to the control section 4. This brake sensor 11 is used for the brake pedal 3
It is composed of a brake pedal switch that detects an operating state of zero.

The control section 4 is also connected to a clutch sensor 13 which detects the operating state of the clutch, that is, the operating state of the clutch pedal. A power source 40 and the like are also connected to the control unit 4.

Next, the control flow in the control unit 4 is shown in FIG.
I will explain mainly. First, in step 101, it is determined whether or not the vehicle is stopped, the affirmative branch moves to step 102, and it is not necessary to operate the braking force increasing means 3 in the negative branch, so this flow ends. In step 102, it is determined whether or not the parking brake is operating, and the affirmative branch moves to step 103 to activate the braking force increasing means 3. Also, step 102
In the negative branch of, this flow ends.

As described above, according to this embodiment, when the vehicle is stopped and the parking brake is operated, the motor 80 of the braking force increasing means 3 is forcibly rotated in the normal direction to increase the braking force. Therefore, the vehicle movement detecting means 2
Even if the vehicle starts moving at an extremely low speed that cannot be detected, or even if the vehicle movement detection means 2 breaks down while the vehicle is stopped,
It is possible to reliably maintain the stop of the vehicle.

The braking force increasing means may use a braking force increasing device of the traction control device for preventing acceleration slip of the vehicle. <Second Embodiment> A second embodiment of the present invention will be described.

In this embodiment, the operating frequency of the braking force increasing means 3 is reduced. The constituent elements of this embodiment are the same as those of the first embodiment, and the description thereof will be omitted.
The control flow of the control unit 4 in this embodiment will be described with reference to FIG.

In step 201, it is judged whether or not the vehicle is stopped, the affirmative branch moves to step 202, and the negative branch ends the present flow. In step 202, it is determined whether or not the parking brake is operating, the affirmative branch moves to step 203, and the negative branch ends the present flow. In step 203, it is judged whether or not the pulling force of the wire of the parking brake is sufficient, that is, whether or not the detection value of the pulling force sensor (parking break sensor) 12 is equal to or more than a preset first threshold value. To be done. This flow ends in the affirmative branch of step 203, and the negative branch moves to step 204 to forcibly activate the braking force increasing means 3 to automatically increase the braking force.

As described above, according to this embodiment, since the braking force of the parking brake is detected and the braking force increasing means 3 is not activated when the parking brake is operating sufficiently, the braking force increasing means 3 It is possible to reduce the operation frequency of.

Instead of the pulling force sensor, a sensor for detecting the lever stroke of the parking brake may be used. This sensor can be composed of a limit switch and a strain gauge. <Embodiment 3> Next, a third embodiment of the present invention will be described.

The present embodiment relates to the case where the vehicle stops on a steep slope. As shown in FIG. 5, the vehicle stop maintaining device according to the present embodiment is provided with a tilt sensor 14 for detecting a slope condition of a road surface.
4 outputs a signal to the control unit 4. Since the other components are the same as those in the first embodiment, the description thereof will be omitted.

Next, the control flow of the control unit 4 of this embodiment will be described with reference to FIG. First, in step 301, it is determined whether or not the wheels are stopped, the affirmative branch moves to step 302, and the negative branch ends the present flow. In step 302, it is determined whether or not the pulling force of the wire of the parking brake is sufficient, that is, whether or not the detection value of the pulling force sensor 12 is equal to or more than a preset first threshold value, and the positive branch ( If the parking brake is operating sufficiently), the process proceeds to step 304, and if the negative branch (if the parking brake is not operating sufficiently), the process proceeds to step 303. In step 304, it is determined whether or not the road surface on which the vehicle is stopped has a steep slope, that is, whether or not the slope detection value from the slope sensor 14 is equal to or greater than a preset second threshold value. Step 304
The affirmative branch moves to step 303, and the negative branch ends this flow. Then, in step 303, the braking force increasing means 3 is operated to automatically increase the braking force.

As described above, according to the present embodiment, the inclination state of the road surface is detected, and in the case of a steep slope, the braking force increasing means 3 is forcibly forced even if the parking brake is sufficiently operated.
I tried to activate. Therefore, even when the vehicle is on a steep slope where it is dangerous to stop the vehicle only with the parking brake (it may start moving), the stopped state of the vehicle can be maintained safely and reliably. <Fourth Embodiment> A fourth embodiment of the present invention will be described.

In this embodiment, the braking force increasing means is operated only when the controller determines that the driver is not performing a driving operation. That is, as shown in FIG. 7, the vehicle stop maintaining device according to the present embodiment detects whether the engine rotation sensor 15 detects the operating state of the engine by measuring the output voltage of the alternator, and whether the gear position is the neutral position. The gear position sensor 16 for detecting whether or not there is provided. Since the other constituent elements are the same as those in the first embodiment, the description thereof will be omitted.

Next, the control flow in the control unit 4 of this embodiment will be described with reference to FIG. First, step 40
At 1, it is determined whether the vehicle is stopped, the affirmative branch moves to step 402, and the negative branch ends the present flow. In step 402, it is determined whether or not the parking brake is operating, the affirmative branch moves to step 403, and the negative branch ends the present flow. Then, in step 404, it is determined whether or not the engine is rotating, the positive branch moves to step 404, and the negative branch moves to step 405. In step 404, it is determined whether or not the gear position is neutral, the affirmative branch moves to step 405, and the negative branch ends the present flow. In step 405, it is determined whether or not the brake pedal is depressed, and the affirmative branch moves to step 406.
This flow ends in the negative branch. Also, step 406
Then, it is determined whether or not the clutch pedal is depressed, the affirmative branch moves to step 407, and the negative branch ends the present flow. Then, in step 407, the braking force increasing means 3 is activated to automatically increase the braking force.

As described above, according to this embodiment, the braking force increasing means 3 is operated only when it is detected that the driver gets off the vehicle or abandons the driving operation. Therefore, it is possible to reduce the frequency of operation of the braking force increasing means 3 while maintaining safety, and it is also possible to improve the durability of the braking force increasing means 3.

[0049]

According to the present invention, it is possible to provide a device for reliably maintaining the stopped state of a stopped vehicle.

Further, it is possible to reduce the frequency of operation of the braking force increasing means of the device for reliably maintaining the stopped state of the stopped vehicle. Further, it is possible to improve the durability of the device that reliably maintains the stopped state of the stopped vehicle.

Further, it is possible to provide a device for surely maintaining the stopped state of the vehicle even when the vehicle is stopped on a steep slope.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a braking force increasing means of the first embodiment.

FIG. 3 is a diagram showing a control flow in a control unit of the first embodiment.

FIG. 4 is a diagram showing a control flow in a control unit according to a second embodiment of the present invention.

FIG. 5 is a configuration diagram showing a third embodiment of the present invention.

FIG. 6 is a diagram showing a control flow in a control unit of the third embodiment.

FIG. 7 is a configuration diagram showing a fourth embodiment of the present invention.

FIG. 8 is a diagram showing a control flow in a control unit of the fourth embodiment.

[Explanation of symbols]

 2. Vehicle movement detecting means 3. Brake force increasing means 4. Control unit 10. Liquid path 11 ... Brake sensor 12 ... Parking brake sensor (pulling force sensor) 13. Clutch sensor 14. Inclination sensor 15 ・ ・ Engine rotation sensor 16 ・ ・ Gear position sensor 20 ・ ・ Wheel cylinder 30 ・ ・ Brake pedal 32 ・ ・ Master cylinder 35 ・ ・ Solenoid valve 37 ・ ・ Indicator lamp 40 ・ ・ Power supply 60 ・ ・ Cylinder body 61 ・ ・ Rotation Stop shaft 62 ··· Communication port 65 ·· Valve body 65a · · Tip surface 66 · · Circumferential groove 67 · · Flow path 68 · · Screw hole 69 · · Axial hole 70 · · Pressure chamber 80 · · Motor 82 · · Output screw shaft

Claims (5)

[Claims] 1. A parking brake sensor for detecting an operating state of a parking brake, a vehicle movement detecting means for detecting a moving state of a vehicle, a braking force increasing means for increasing a braking force, and the parking brake sensor and vehicle movement detection. Means and a control unit connected to the braking force increasing unit, wherein the control unit increases the braking force on the condition that the stop of the vehicle is detected and the operation of the parking brake is detected. A stop-maintaining device for a vehicle, which operates the means. 2. The parking brake sensor includes a pulling force sensor that detects a pulling force of a wire that connects a parking lever of the parking brake and a brake operating unit, and the controller controls the detection value of the pulling force sensor. When the braking force increasing means is less than the first set value, the braking force increasing means is operated, and when the detection value of the pulling force sensor is equal to or more than the first setting value, the braking force increasing means is controlled to the inoperative state. The vehicle stop maintaining device according to claim 1, wherein the stop maintaining device is a vehicle. 3. An inclination sensor, which is connected to the control unit, for detecting an inclination state of a road surface, wherein the control unit controls the brake when the inclination detection value from the inclination sensor is equal to or more than a second set value. 3. The vehicle stop maintaining device according to claim 2, wherein the force increasing means is operated. 4. The vehicle stop maintaining device according to claim 1, wherein the control unit actuates the braking force increasing means only when it is determined that the driver is not performing a driving operation. 5. An engine rotation sensor connected to the control unit for detecting an operating state of an engine, a foot brake sensor for detecting an operating state of a foot brake, a clutch sensor for detecting an operating state of a clutch, and a gear position. And a gear position sensor for detecting whether the vehicle is in a neutral position. Is in the neutral position or detects that the engine has stopped, that the foot brake has not been activated, and that the clutch has not been activated. 5. The brake force increasing means is operated when it is determined that the brake force has not been applied, and the brake force increasing means is operated. Two-way stop maintaining device.