JP3323566B2 - Method of checking operation of vehicle brake system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation check method for checking the operation of a hydraulic unit of an anti-lock brake device and a traction control device provided in a brake device of a vehicle such as an automobile.

[0002]

2. Description of the Related Art In recent years, an anti-lock brake device (hereinafter referred to as ABS) is mounted on a hydraulic system of a brake device of an automobile to prevent wheel lock at the time of sudden braking or braking on a low μ road. Stability and maneuverability are secured, and the braking distance is shortened. In addition, a traction control device (hereinafter, referred to as a TCS) is mounted to prevent a drive wheel from slipping at the time of sudden start or the like, and control to secure directional stability and maneuverability has been adopted.

[0003] In each of these devices, a signal such as a wheel speed is electrically processed by a control unit, and the control signal is output to a hydraulic unit arranged in a hydraulic system. Each valve of the hydraulic unit, a motor pump, and an accumulator are output. The electronic control of the brake fluid pressure of the wheel cylinder of the wheel is performed by operating the above. Here, in the ABS, when the brake pedal is depressed during braking, the hydraulic unit
For example, control is performed so that the brake fluid pressure of all four wheels is reduced, maintained, and increased. Further, in the TCS, the hydraulic fluid unit is controlled so that the brake fluid pressure of only the drive wheels is increased, maintained, and reduced, for example.

[0004] On the other hand, generally after a vehicle is manufactured, the operation of various devices is checked.
The operation of the hydraulic units of BS and TCS is checked.
In this case, the method of checking each component of the hydraulic unit individually increases the number of work steps and causes various problems when attaching and detaching the components. In the sequence check method using an external signal, only a few test patterns can be provided. Cannot check each part in detail. Further, in the method of directly applying a signal to the harness, since the test is performed differently from the configuration of the system, there are disadvantages such as poor accuracy. Therefore, when the brake device is provided with a hydraulic unit that is operated by a plurality of control systems, it is necessary to appropriately and quickly check the operation in consideration of the configuration of each system.

Conventionally, as a method of checking the operation of the brake device, there is a prior art disclosed in Japanese Patent Application Laid-Open No. 64-67466, for example. Here, when checking the operation of the anti-skid device mounted on the brake device,
A pseudo signal generation circuit for generating an ABS check mode operation signal is provided in the control circuit in advance. Then, when a check operation command of a predetermined signal pattern is input from the brake pedal switch, the pseudo signal generation circuit outputs an operation signal of a check mode in which depressurization, holding, and pressurization are combined in a certain order to the actuator to operate. It is also shown that a brake tester is provided on the wheel side to measure the braking force at each time of pressure reduction, holding, and pressure operation, and to determine whether the braking force is normal based on the value of the braking force.

[0006]

However, in the above-mentioned prior art, since the operation is checked by the signal pattern of the brake pedal switch, it cannot be applied to the operation check of the traction control device. Further, since the operation is checked by the control circuit itself, there is a problem that data on the operation state of the actuator cannot be obtained.

The present invention has been made in view of this point, and when hydraulic units of a plurality of control systems are mounted on a brake device, the operation of the hydraulic units is optimized in the same manner as the configuration of each system. It is an object of the present invention to check quickly and obtain data of an operation state as needed to improve check accuracy and the like.

[0008]

In order to achieve the above object, the present invention provides a brake for a vehicle provided with a hydraulic unit.
The oil device according to a signal from the control unit.
Electronic control to activate the pressure unit
Brake control (ABS) and traction control (TC
S) to check the operation of the vehicle brake system
In the method, the pressure is reduced, maintained, and increased by one cycle A
One cycle of BS check pattern, pressure increase, hold, and pressure reduction
Operation check professional with TCS check pattern
Connect a diagnostic tool that has a program to the above control unit
Input from the diagnostic tool
When the brake pedal is depressed, the ABS
The brake pattern, and then release the brake.
And operate according to the above TCS check pattern.
The braking force of the wheel at the point is detected by a brake tester and the oil
Continuous operation of ABS control system and TCS control system of pressure unit
And check it.

[0009]

According to the above-described operation check method, the commands of the operation check program are individually input to the control unit from the diagnostic tool, the control unit is operated as instructed, and the hydraulic unit is turned on and off by depressing and releasing the brake pedal. By operating in the same manner as in the configuration, the operation of the components of the antilock control system and the traction control system of the hydraulic unit is continuously and promptly and accurately checked. Further, it becomes possible to obtain detailed data from the control unit to the diagnostic tool as needed.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, an outline of an entire operation check system in a configuration in which ABS and TCS are mounted on a brake device will be described. In the brake device 1, a brake line 4 from a master cylinder 3 having a brake pedal 2 is connected to a wheel cylinder 6 of a wheel 5, and a hydraulic unit 10 for ABS and TCS is provided in the brake line 4. A brake tester 7 is provided on the wheel 5 so as to detect a braking force.

The control unit 30 controls ABS control, TCS
Control and self-diagnosis programs for fail-safe control. In addition, a diagnostic tool 8 using a personal computer is used for the operation check, and an operation check program 9 is input to the diagnostic tool 8. The operation check program 9 is the same as the control unit 30
The diagnostic tool 8 has an ABS check pattern and a TCS check pattern, and commands for each operation are sequentially output by the operation of the diagnostic tool 8.

To check the operation, the diagnostic tool 8 is connected to the control unit 30, the operation check program 9 is executed, and the brake pedal 2 is depressed. Then, the control unit 30 is operated based on the individual command of the program 9, and an operation signal of one cycle of pressure reduction, holding, and pressure increase and a motor drive signal are output to the hydraulic unit 10 according to the ABS check pattern to operate it. . The braking force at each operation is detected by the brake tester 7 to check whether the ABS valve system is normal. At this time, detailed data is sent from the control unit 30 to the diagnostic tool 8 as necessary, and the process ends.

Thereafter, in a state where the depression of the brake pedal 2 is released, this time it is turned on by the TCS check pattern.
An OFF signal, an operation signal for one cycle of pressure increase, hold, and pressure reduction, and a motor drive signal are output to the hydraulic unit 10 again to be operated. Also in this case, the braking force at each operation point is detected by the brake tester 7, it is checked whether the TCS valve system is normal or not, and the data is sent to the diagnostic tool 8 if necessary, and the process is terminated.

Referring to FIG. 2, a specific configuration of the brake device 1 will be described. One of the brake lines 4a, 4b from the master cylinder 3 having the brake pedal 2 is
The right front wheel FR communicates with the wheel cylinders 6, 6 of the left rear wheel RL, and the other brake pipelines 4c, 4d communicate with the left front wheel FL and the wheel cylinders 6, 6 of the right rear wheel RR. Therefore, the ABS 11 of the hydraulic unit 10 is provided with an FR valve 12a, an FL valve 12c, an RR valve 12d, and an RL valve 12b which are respectively switched to three positions in a pipeline of four wheels. The drain line 13 from the FR valve 12a and the RL valve 12b, the FL valve 12c and the RR valve 12
A drain line 14 from d communicates with the accumulators 16a and 16b of the pump device 15. The pump device 15 has two pumps 18a and 18b driven by a motor 17, and one of the pumps 18a stores a high hydraulic pressure in an accumulator 19a, and a right front wheel FR and a left rear wheel RL are connected by a pipeline 20.
, And the other pump 18b is configured to store high hydraulic pressure in the accumulator 19b and increase the pressure of the left front wheel FL and the right rear wheel RR simultaneously by the pipeline 21.

The TCS 25 utilizes the ABS 11 described above, and the reservoir 3a of the master cylinder 3 communicates with the accumulators 16a and 16b of the pump device 15 via a pipe 27 having a brake valve 26. In the case of FF vehicles, the left and right front wheels are drive wheels,
TCS valves 28a and 28b are provided on the master cylinder 3 side of the pipelines 4a and 4c of the left and right front wheels FL and FR.

Next, the operation of the brake device 1 will be described. First, in a normal state, only the brake valve 26 is closed as shown in the figure, and the two TCS valves 28a and 28b are open, and all the four-wheel valves 12a to 12d are in the pressure increasing position. As a result, when the brake pedal 2 is depressed during braking, the hydraulic pressure generated in the master cylinder 3 is directly applied to each of the four wheel cylinders 6 to perform a braking action. If the wheel deceleration exceeds the set value during braking, the four-wheel valve 1
2a to 12d are switched to the holding positions to hold the brake pressure, and when the wheels are about to be locked, the four-wheel valves 12
The brake pressure is drained to the accumulators 16a and 16b by the drain lines 13 and 14, and the pressure is reduced. At this time, the pump 17 is
8a and 18b are operated to store the accumulators 19a and 19b.
Store high hydraulic pressure in b. On the other hand, when the deceleration of the wheels is alleviated due to the reduction in the brake pressure, the above-mentioned holding state is again achieved, and then the high hydraulic pressure of the accumulators 19a and 19b acts on the four wheel cylinders 6 by moving to the pressure increasing position to cause the wheels to rotate. Braking is performed, and control is performed so as to prevent wheel lock.

On the other hand, at the time of acceleration beyond a predetermined throttle opening, the brake valve 26 is opened to replenish the oil in the reservoir 3a, the TCS valves 28a and 28b are closed and restricted to the front wheel side, and the FR valve 12a and the FL valve 12c
Is a holding position, and the wheel cylinders 6, 6 of the left and right front wheels FL, FR are shut off from the brake lines 4a, 4c. Further, the pumps 18a and 18b are operated by the motor 17, and the high hydraulic pressure is stored in the accumulators 19a and 19b. When the wheel acceleration exceeds the set value, the front left and right wheels FL, F
After the R valves 12a, 12c are in the pressure increasing position, they are switched to the holding position, whereby high hydraulic pressure is applied to the left and right front wheels FL, F.
It acts on the wheel cylinders 6, 6 of R to brake. When the acceleration of the wheels is reduced by this braking, the valve 12
A and 12c are depressurized positions and braking is released, and control is performed to prevent wheel slip. Therefore, ABS control and TCS control can be performed by the hydraulic unit 10 configured as described above.

Referring to FIG. 3, the configuration of the control unit 30 will be described. The control unit 30 has a CPU 32, and signals from various sensors 40 such as four-wheel speeds are input to the CPU 32 via a waveform shaping circuit 33, and the operation of an ignition switch 41 stabilizes the battery power by the power supply circuit 34 and the CPU 32 Supplied to The valves 12a to 12d, 26, 28a, and 28 of the hydraulic unit 10 are output from the CPU 32 via a drive circuit 35 in response to an output signal.
b, an operation signal is output to the motor 17 and the like, and a signal is output to the lamp 42, the monitor line 43 and the like by the other input / output circuit 36. Further, the control unit 30 has a communication interface 37, and inputs a command of the diagnostic tool 8 to the CPU 32 at the time of operation check, and the operation check program 9
It is configured to operate as instructed by.

The operation of checking the operation of the hydraulic unit 10 will now be described with reference to the flowchart of FIG. 4 and the time chart of FIG. First, in step S1, the diagnostic tool 8 is connected to the control unit 30, and in step S2, the brake pedal 2 is depressed to increase the brake pressure of all four wheels (t0). Then, in step S3, the operation check program 9 is executed to give an operation command according to the ABS check pattern, and the control unit 30 is operated according to the command. Then, first, the motor 17 is operated (t1), and the FR valve 12a and the RR valve 12d are simultaneously operated in one cycle of pressure reduction, holding, and pressure increase (t2). Therefore, in the case of normal operation, the FR brake pressure and the RR brake pressure decrease, maintain the reduced state, and change so as to increase.

Thereafter, the FL valve 12c and the RL valve 12b are operated in the same manner (t3). In this case, if normal, the FL brake pressure and the RL brake pressure change similarly. Then, the motor 17 is stopped and the process ends (t4). Further, the state of the brake pressure at each of the above operation times is detected by the brake tester 7, and based on this value, the ABS is determined in step S4.
It is determined whether the valve system is normal or not.
The operation of the parts of BS11 is checked.

Next, if the ABS 11 is normal, the depression of the brake pedal 2 is released in step S5 (t
5). Then, in step S6, the operation check program 9 is executed again, and an operation command is issued this time according to the TCS check pattern. Therefore, the FR valve 12a and the FL valve 1
2c is held (t6) and the two TCS valves 28
a, 28b to close (t7), the motor 17
Is operated (t8). After that, first, the FR valve 12a is operated in one cycle of increasing, maintaining, and decreasing the pressure (t).
9) When this is normal, F is applied as described with reference to FIG.
The R brake pressure increases, and this state is maintained and changes so as to decrease.

Next, the FL valve 12c is operated in the same manner to
The L brake pressure is changed (t10). Thereafter, the TCS valves 28a and 28b are opened (t11), and the FR valve 1
2a and the FL valve 12c are returned to the original state (t12), the motor 17 is stopped, and the process is terminated (t13). Also in this case,
The brake pressure is detected by the brake tester 7, and it is determined in step S7 whether the TCS valve system is normal.
The operation of the 25 parts is checked. At the time of this operation check, data on the valve operation state is sent to the diagnostic tool 8 as necessary.

[0023] When the operation check of the hydraulic unit 10 exits in a normal state, the diagnosis in step S8 tool 8
Disconnect. If abnormal, the brake piping and parts of the hydraulic unit 10 are inspected and repaired in step S9.

Although the embodiment of the present invention has been described above, the present invention can be applied to the case where the configuration of the hydraulic unit is different and the case where the number of control systems is three or more.

[0025]

As described above, according to the present invention,
In a configuration in which multiple hydraulic systems of anti-lock control and traction control are mounted on the vehicle's brake device, an operation command is issued by the operation check program of the diagnostic tool, and one operation of depressing and releasing the brake pedal
In this method, the hydraulic unit is continuously operated and checked according to two types of check patterns. Therefore, it is possible to quickly and accurately check the operation of the antilock control system and the traction control system of the hydraulic unit. it can.
Further, the configuration of the control unit is simplified. Since the hydraulic unit operates in the same manner as the configuration of each system based on the operation check program, the hydraulic unit can be checked accurately and can have many check patterns. In addition, since detailed data can be obtained from the control unit to the diagnostic tool as needed, check accuracy and the like are improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an outline of an embodiment of a method for checking operation of a vehicle brake device according to the present invention.

FIG. 2 is a circuit diagram showing a specific example of a hydraulic unit.

FIG. 3 is a block diagram showing a specific example of a control unit.

FIG. 4 is a flowchart showing an operation of an operation check.

FIG. 5 is a time chart showing an operation check state.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 brake device 4, 4 a to 4 d brake line 7 brake tester 8 diagnostic tool 9 operation check program 10 hydraulic unit 11 ABS 25 TCS 30 control unit

Continuation of front page (56) References JP-A-5-240742 (JP, A) JP-A-4-369453 (JP, A) JP-A-4-215032 (JP, A) JP-A-64-67466 (JP) JP-A-63-17162 (JP, A) JP-A-1-111558 (JP, A) JP-A-4-1481 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB Name) B60T 8/32-8/96 G01M 17/00

Claims (3)

(57) [Claims] A brake for a vehicle provided with a hydraulic unit.
The oil device according to a signal from the control unit.
Electronic control to activate the pressure unit
Brake control (ABS) and traction control (TC
S) to check the operation of the vehicle brake system
In the method, reduced pressure, holding, ABS check path for the pressure increasing and 1 cycle
TCS with turn, pressure increase, hold, and pressure reduction as one cycle
Have an operation check program with check patterns
Diagnostic tool connected to the control unit, and the hydraulic unit
Check the above ABS by depressing the brake pedal
Operate in a pattern and then release the brake
To operate according to the above TCS check pattern, and detect the braking force of the wheel at each operating point with a brake tester.
Operation of the ABS control system and TCS control system of the hydraulic unit
For vehicles, characterized by continuously checking for
How to check the operation of the key device. Wherein said diagnosis tool is optionally operated check method for a vehicle brake system according to claim 1, characterized in that to obtain the data of the working checked from the system <br/> control unit. Wherein said hydraulic unit is respectively provided in the brake conduit of the at least four wheels and anti-lock brake
A valve that switches to the pressure increase, hold, and pressure reduction positions during key control and traction control, a pump device that has a motor pump and accumulator to generate high hydraulic pressure, and is limited to drive wheels during traction control The method for checking operation of a vehicle brake device according to claim 1 , further comprising a valve that performs an anti-lock brake control and a traction control.