JPH10315938A - Automatic emergency braking device for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a stop distance at the time of emergency braking of an automobile so as to avoid an accident such as collision or reduce a speed of a vehicle when an accident occurs so as to improve the safety. SOLUTION: When an emergency brake is applied, the movement of a foot 15 which changes its stepping on from an accelerator pedal 8 to a brake pedal 9 is detected by an accelerator position sensor 12 and a heel part contact sensor 13. When a brake controller 29 judges that the emergency brake is being applied based on the results of the detection, it sends a control signal to a braking force load device 17. The braking force load device 17 applies hydraulic pressure applied on an emergency brake pipe 19 from a pressure source device for brake 18 to a brake pipe 11 through a solenoid valve 22 and an emergency brake pipe 20 to operate a wheel cylinder 7 and a brake shoe 5. A brake device is operated before a driver operates the brake pedal 9 to generate braking force of a vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emergency automatic braking system for an automobile used for automatically operating a brake when a driver of the automobile attempts an emergency braking operation.

[0002]

2. Description of the Related Art In general automobiles, there are many systems in which separate operation pedals are both operated with a right foot when accelerating and braking the vehicle. In a vehicle of this type, when the driver attempts to apply a brake while driving, it is necessary to release the right foot from the accelerator pedal and depress the pedal toward the brake pedal.

[0003]

SUMMARY OF THE INVENTION
In the method of switching from the pedal to the brake pedal, after the driver determines that the brake operation is necessary,
Until the actual operation of the brake, a time for switching from the accelerator pedal to the brake pedal and a time for depressing the brake pedal are required. This time is generally referred to as idle running time, and during emergency braking, during this time the vehicle is in an idle running state waiting for braking, even though the driver intends to brake. ing.

Therefore, shortening the idle running time has been a very important problem in order to shorten the stopping distance of the vehicle during emergency braking and to enhance safety. For this reason, conventionally, the operating height of each pedal, the positional relationship, and the like have been studied, but the pedal depressing time itself is required as long as this type of driving method is used, and this is dramatically shortened. In fact, the method of doing so has not been realized.

The present invention has been made to solve the above-mentioned conventional problems, and can reduce the stopping distance at the time of emergency braking of an automobile. Therefore, an accident such as a collision can be avoided or an accident can be prevented. It is an object of the present invention to provide an emergency automatic braking device for a vehicle which can reduce the speed of the vehicle and improve safety.

[0006]

SUMMARY OF THE INVENTION In order to solve the above problems, an emergency automatic brake device for a vehicle according to the present invention comprises an accelerator position sensor for detecting a return speed of an accelerator pedal,
A heel contact sensor that is disposed on the floor below the accelerator pedal and detects a change in the contact state of the heel of the foot that operates the accelerator pedal, and a braking force load device for generating a braking force, Based on the output from the accelerator position sensor and the heel contact sensor, it is determined whether the driver is in a state of performing emergency braking, and when it is determined that the driver is in a state of performing emergency braking, And a brake control device for operating the braking force load device.

According to another aspect of the present invention, there is provided an emergency automatic braking apparatus for a vehicle, comprising a brake operation sensor for detecting the presence or absence of an operation of a brake pedal. After the emergency automatic brake is applied by the braking force load device based on the output from the operation sensor, the brake
The operation of the braking force load device is canceled when it is determined that the pedal has not been operated and when it is determined that the brake pedal has been operated but the operation has been subsequently stopped.

In the above construction, the braking force load device is configured to brake the brake pressure source device and a brake pedal for supplying a brake fluid for operating the brake pedal with the brake pressure source device. An emergency brake pipe for supplying and returning a working fluid, and switching means for selectively connecting or disconnecting the emergency brake pipe with the brake pipe according to a control signal from a brake control device. Or a braking force loading device is provided between the brake pedal and the master cylinder, a pipe through which gas flows into a negative pressure chamber on one side of the power piston in the vacuum booster, and a pipe provided in the middle of the pipe. And a switching unit that opens and closes in response to a control signal from the brake control device.

According to the present invention configured as described above,
When a driver of a car tries to perform an emergency braking operation,
The operation of the foot to change from the accelerator pedal to the brake pedal is detected by the accelerator position sensor and the heel contact sensor, and when the brake control device determines that the emergency braking is performed based on the detection result, the driver performs the braking operation. -It is possible to generate the braking force of the vehicle by operating the braking force load device before operating the pedal, whereby the stopping distance at the time of emergency braking of the vehicle can be shortened.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. First, a first embodiment of the present invention will be described. FIG. 1 is a schematic configuration diagram showing an automotive emergency automatic brake device according to a first embodiment of the present invention.

In FIG. 1, 1 is a wheel of an automobile,
A brake drum 3 is provided inside the tire 2, a lining 4 is provided inside the brake drum 3, and a pair of brake shoes 5 are rotatably supported inside the lining 4, and the brake shoes 5 It is urged by a spring 6 to the side separated from the lining 4. A piston rod 7a projecting from both sides of the wheel cylinder 7 is connected between the pair of brake shoes 5. Reference numeral 8 denotes an accelerator pedal capable of adjusting the traveling speed of the vehicle by operating the right foot, 9 denotes a brake pedal operated by the right foot, and 10 denotes an operation of the piston rod 10a by operating the brake pedal 9. The master cylinder 11 is a brake pipe that connects the master cylinder 10 and the wheel cylinder 7. When the brake pedal 9 is depressed, the piston rod 10a and the piston (not shown) of the master cylinder 10 are pushed, hydraulic pressure is transmitted through the brake pipe 11, and the piston of the wheel cylinder 7 of each wheel 1 is moved. (Not shown) and the piston rod 7a are actuated to spread the brake shoe 5 against the elasticity of the spring 6, press the brake shoe 5 against the lining 4 inside the brake drum 3, and stop the rotation of the wheel 1 by the friction. Can be done.

Reference numeral 12 denotes an accelerator position sensor for detecting the return speed of the accelerator pedal 8, and reference numeral 13 denotes a heel contact sensor, which is disposed on the floor 14 below the accelerator pedal 8 and is located on the right side for operating the accelerator pedal 8. A change in the contact force or the contact position, which is the contact state of the heel portion 15a of the foot 15, is detected. Reference numeral 16 denotes a brake operation sensor that detects whether or not the brake pedal 9 is operated.

Reference numeral 17 denotes a braking force load device, which supplies a brake pressure source device 18 and pressure oil from the brake pressure source device 18 to the brake pipe 11, and supplies pressure oil from the brake pipe 11 to the brake pressure. First, second and third emergency brake pipes 1 for returning to the source device 18
9, 20, 21 and emergency brake pipes 19, 20,
The solenoid valve 22 is selectively connected to the brake pipe 11 or is switched to shut off. The brake pressure source device 18 includes a pressurized oil tank 23, a pump 25 that sends out pressurized oil 24 in the pressurized oil tank 23, and a motor 26 that drives the pump 25.
A check valve 27 for preventing a back flow of the pressure oil 24 sent from the pump 25, and a first check valve of the pressure oil sent from the check valve 27.
Of pressure on the emergency brake pipe 19 (accumulation)
And an accumulator 28 for performing the following. When the pressure in the first emergency brake pipe 19 communicated with the accumulator 28 reaches a predetermined pressure by the operation of the accumulator 28, the motor 26 stops driving and stops driving the pump 25. When the pressure decreases, the motor 26 is automatically driven. Pump 25
Is driven. The second emergency brake pipe 20 is connected to the brake pipe 11, and the third emergency brake pipe 21 is connected to the pressure oil tank 2.
Opened to 3. In addition, the solenoid valve 22
Is configured to shut off the emergency brake pipes 19, 20, and 21 so that the emergency brake pipes 19 and 20 can communicate with each other and the emergency brake pipes 20 and 21 can communicate with each other.

Reference numeral 29 denotes a brake control unit, which comprises a memory unit 30, a logic circuit unit 31, and a control output unit 32. The memory unit 30 can temporarily store detection signals output from the accelerator position sensor 12, the heel contact sensor 13, and the brake operation sensor 16. The logic circuit unit 31 can determine whether or not the driver is about to perform emergency braking based on the detection signal stored in the memory unit 30 and can also determine the release of braking. The output control unit 32 sends out a control signal based on the determination result of the logic circuit unit 31 to control the switching operation of the solenoid valve 22. That is, the first, second, and third emergency brake pipes 19, 20,
21 can be shut off, the first and second emergency brake pipes 19 and 20 can be connected during automatic braking operation, and the second and third emergency brake pipes 20 and 21 can be connected during automatic brake release. .

The above configuration will be described in further detail below together with its operation. When this device starts up, the motor 2
6 drives the pump 25 to pump the pressure oil 24 in the pressure oil tank 23 to the first emergency brake pipe 19 via the check valve 27. Then, when the accumulator 28 accumulates a predetermined pressure, the driving of the motor 26 and the pump 25 is stopped, and this state is maintained. Here, if the driver depresses the accelerator pedal 8 to the brake pedal 9 to perform emergency braking, first, the accelerator position sensor 12 determines that the return speed of the accelerator pedal 8 by the driver's operation is equal to or higher than a certain value. It is detected that the driver has been present and the accelerator pedal 8 has returned to the original position (off position). Detect that there is.

These detection signals are transmitted to the brake controller 29.
Of the accelerator position sensor 1 in the logic circuit 31 based on these detection signals.
If the detection by both the heel contact sensor 2 and the heel contact sensor 13 is within a fixed short period of time and it is predicted / determined that the driver is about to perform emergency braking, a control signal is output from the control output unit 32. Activate the solenoid valve 22 so that the first emergency brake pipe 19 and the second emergency brake pipe
The pipe 20 is connected to the brake pipe 11 to apply pressure. Accordingly, the piston of the wheel cylinder 7 and the piston rod 7a are operated, the brake shoe 5 is pushed out against the elasticity of the spring 6, and the brake shoe 5 is pressed against the inside of the brake drum 3 to be in a braking state. it can. After the driver depresses the brake pedal 9, the master cylinder 10 operates to apply pressure to the brake pipe 11 as described above, and the brake state is applied by the pressure applied from the emergency brake pipes 19 and 20. And the vehicle can be stopped.

As described above, the driver can return the accelerator pedal 8 and switch to the brake pedal 9 at the time of emergency braking to determine that the vehicle is in a braking state quickly. Therefore, it is possible to almost eliminate the idle running time due to the pedal depressing required in the conventional brake operation.

Generally, the idle running time is 0.1 second to 0.1 second.
Although it is said to be about 4 seconds, as a result of an experiment conducted by 59 drivers, the maximum value of the idle running time (step-change time + step-in time) of the experiment performed 5 times for each subject is on average. It took about 0.3 seconds. Assuming that the idle running time is reduced to 0.3 seconds and the braking deceleration by this device is set to 1 G, when emergency braking is required, the traveling speed can be reduced by about 10 km / h before the brake operation is performed. It will be. Also,
In terms of the stopping distance, a vehicle traveling at a speed of 60 km / h is about 5 m in front and 120 km in the same way.
/ H, it can be stopped about 10 m before.

The logic circuit unit 31 checks the presence / absence of a detection signal from the brake operation sensor 16 in the memory unit 30. After the braking operation by the present device, the driver does not operate the brake pedal 9 within a short time. If it is determined that the brake pedal 9 has been operated by the driver, but it is subsequently determined that the operation has been stopped, a control signal is output from the control output unit 32 and the solenoid valve 2 is output.
Activate the second emergency brake pipe 20 and the third emergency brake pipe 20
Of the brake pipe 11 is released, and the pressurization of the brake pipe 11 is released. Accordingly, the brake shoe 5 is separated from the brake drum 3 by the repulsive resilience of the spring 6, and the hydraulic oil discharged from the wheel cylinder 7 with the retraction of the piston rod 7a of the wheel cylinder 7 is subjected to the second emergency. Return to the pressure oil tank 23 via the brake pipe 20, the solenoid valve 22, and the third emergency brake pipe 21. On the other hand, the brake control device 29
In, the logic circuit section 31 clears the memory section 30. After the release, the solenoid valve 22 is returned and operated by a control signal from the control output unit 32 to shut off the first, second, and third emergency brake pipes 19, 20, and 21 to return to a normal operation state, and To respond to emergency braking.

Next, a description will be given of a second embodiment of the present invention. FIG. 2 is a schematic configuration diagram of a main part showing an emergency automatic braking device for a vehicle according to a second embodiment of the present invention.

The feature of the present embodiment is that, as shown in FIG.
A vacuum booster 33 for a vacuum servo of a brake inserted between the brake cylinder and the master cylinder 10; an air cleaner 34 and an emergency brake pipe 35 which are connected to operate the vacuum booster 33 and supply the atmosphere; And a solenoid valve 36 inserted in the middle of the emergency brake pipe 35 and controlled by a control signal from the brake control device 29 (see FIG. 1). Other configurations are the same as those in the first embodiment.

According to the present embodiment, similarly to the first embodiment, the air cleaner 34 and the emergency brake pipe 3 are opened by opening the solenoid valve 36 according to a control signal output from the brake control device 29 during emergency braking.
5 to the negative pressure chamber on one side of the power piston of the vacuum booster 33, whereby the first
The brake can be operated similarly to the embodiment.

According to the present embodiment, in the case of a vehicle having a vacuum booster 33 in advance, the connection can be made particularly simply and inexpensively by connecting the auxiliary brake pipe 35. In the case of a vehicle that does not have the vacuum booster 33 in advance, it is only necessary to newly provide the vacuum booster 33 and the like.

In each of the above embodiments, a predetermined braking operation is performed irrespective of the state of the road surface of the running vehicle, so that the movement of the vehicle does not become unstable on a slippery road surface or the like. In addition, if necessary, an adjusting device (ABS system) that detects a wheel slip or the like and controls the pressure on the brake pipe 11 to control the braking force can be used together.

The present invention is intended to bring the vehicle into a braking state as soon as possible when emergency braking is required. For the braking force load device 17 itself, a method other than the first and second embodiments can be adopted. Also, the brake device is not limited to the hydraulic system, but can be applied to various other systems such as a pneumatic system and the like. Can be applied. The release of the emergency braking can be realized by operating a switch or the like instead of detecting the brake pedal 9 by the brake operation sensor 16.
In addition, the present invention can be variously changed in design without departing from the basic technical idea.

[0026]

As described above, according to the present invention, when the driver of an automobile attempts to perform an emergency braking operation, the operation of the foot to change from the accelerator pedal to the brake pedal is performed by the accelerator position sensor or the heel. When the brake control device determines that emergency braking is performed based on the detection result, the braking force load device is operated before the driver operates the brake pedal, and the braking force of the vehicle is reduced. Can be generated, whereby the stopping distance at the time of emergency braking of the vehicle can be shortened. Therefore, an accident such as a collision can be avoided or the speed of the vehicle at the time of the accident can be reduced to improve safety.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an automotive emergency automatic braking device according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a main part showing an emergency automatic braking device for a vehicle according to a second embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 wheel 3 brake drum 5 brake shoe 7 wheel cylinder 8 accelerator pedal 9 brake pedal 10 master cylinder 11 brake pipe 12 accelerator position sensor 13 heel contact sensor 16 brake operation sensor 17 braking load device 18 brake Pressure source device 19 Emergency brake pipe 20 Emergency brake pipe 21 Emergency brake pipe 22 Solenoid valve 28 Accumulator 29 Brake control unit 33 Vacuum booster 35 Emergency brake pipe 36 Solenoid valve

Claims (4)

[Claims] An accelerator position sensor for detecting a return speed of an accelerator pedal, and a change in ground contact state of a heel portion of a foot for operating the accelerator pedal, which is disposed on a floor below the accelerator pedal. Whether the driver is about to perform emergency braking based on the outputs from the heel contact sensor, the braking force load device for generating the braking force, and the accelerator position sensor and the heel contact sensor And a brake control device for operating the braking force load device when it is determined that emergency braking is to be performed. 2. A brake operation sensor for detecting the presence or absence of operation of a brake pedal, wherein a brake control device performs emergency automatic braking by an operation of a braking force load device based on an output from the brake operation sensor. After that, when it is determined that the brake pedal has not been operated within a certain period of time and when the brake pedal has been operated, and thereafter it is determined that the operation has been stopped, the operation of the braking force load device is performed. 2. The emergency emergency braking system for an automobile according to claim 1, wherein said emergency automatic braking device is configured to release. 3. A brake force supply device for supplying a brake fluid between a brake pressure source device and a brake pipe for supplying a brake fluid for operating a brake pedal with the brake pressure source device. And an emergency brake pipe for performing a return from the brake pipe, and switching means for selectively connecting or disconnecting the emergency brake pipe with the brake pipe according to a control signal from a brake control device. 2. The emergency automatic braking device for vehicles according to 2. 4. A pipe for flowing gas into a negative pressure chamber on one side of a power piston in a vacuum booster inserted between a brake pedal and a master cylinder, and a braking force loading device is provided in the middle of the pipe. The emergency automatic braking device for a vehicle according to claim 1 or 2, further comprising: a switching unit that is provided and opens and closes in response to a control signal from a brake control device.