JPH04221738A - Operation confirming device for antiskid brake system - Google Patents

Abstract

PURPOSE:To prevent the occurrence of unevenness in evaluation and to improve decision precision by conducting detection by means of a brake tester, and deciding propriety based on a given decision condition by means of a computing processing device. CONSTITUTION:A whole brake is applied to a vehicle 5 to be inspected. The brake master cylinder of the vehicle 5 continues the generation of a maximum brake liquid pressure but when an antiskid brake system(ABS) is in a normal state, a brake fluid pressure on the wheel cylinder side is hardly increased to prevents the occurrence of the slip of a wheel. Thereby, a brake tester 4 outputs a brake force value being within a given range slightly higher than the rolling resistance value of a wheel. Meanwhile, when the ABS is not in a normal state, the tester 4 outputs a high brake force value. A computing processing device 9 inputs the brake power value of each wheel outputted from the tester 4, analyzes the change state of the brake power value, and compares the analyzing result with a decision condition to decide propriety of operation of the ABS.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] This invention relates to a device for easily confirming the operation of an anti-skid brake system (A.B.S) installed in a vehicle to prevent wheels from locking during full braking. It is.

0002

[Prior art] Inspection on the inspection line of a vehicle assembly factory, etc.
There are times when it is necessary to simply check whether a vehicle's anti-skid brake system is operating normally. A conventional method for checking the operation in such a case is to use, for example, a high-speed brake tester shown in FIG. By doing so, the speed of the wheels is increased to the equivalent of a vehicle speed of approximately 25 km/h, and the vehicle under test is put into a simulated running state.In this state, the inspector on board the vehicle under test applies full brakes, and the wheels are The anti-skid brake system is activated by inducing locking, and during the operation, as shown in FIG. The number of times the amplitude increases or decreases within a predetermined time T is counted, and if the number of times n exceeds a predetermined determination value, it is determined that the anti-skid brake system has operated normally.

As another conventional method, for example, the vehicle to be inspected is actually driven and enters a low μ road surface with a low coefficient of friction at a predetermined vehicle speed, and at the same time as the vehicle enters, an inspector riding on the vehicle to be inspected The anti-skid brake system is fully applied and the anti-skid brake system is activated, the degree of kickback to the brake pedal that occurs when the anti-skid brake system is activated, whether the vehicle being inspected maintains a straight line, and whether it is possible to change course by steering operation. There is a method for determining whether the anti-skid brake system is normal or not based on the vehicle behavior such as whether the anti-skid brake system is normal or not, and the stopping distance of the vehicle to be inspected.

[0004] As another conventional method, for example, as shown in FIG.
In this method, the speed of the wheels of the vehicle to be inspected 4 placed on the free roller tester 3 is determined by an inspector riding the vehicle 4 by operating the accelerator pedal to increase the vehicle speed to approximately 25 km by the engine of the vehicle 4. The vehicle to be inspected 4 is put into a simulated running state by increasing the speed to the equivalent of /h, and in that state,
The inspector on board Vehicle 4 applies full brakes to activate the anti-skid brake system, and intuitively determines whether the anti-skid brake system is normal based on the degree of kickback to the brake pedal that occurs during activation. Determine whether

[0005]

[Problems to be Solved by the Invention] However, the conventional method described at the beginning has the problem that the device is expensive because it requires a large-capacity electric motor, and that it causes damage to the tire surface because it performs sudden braking from high speed. There is a problem that this may occur. There is a problem in that relatively inexpensive medium-speed or low-speed brake testers cannot increase the speed of the wheels to a level equivalent to the lower limit vehicle speed for anti-skid brake system operation, making it impossible to carry out inspections. Furthermore, the conventional method described in the second section has the problem that a wide range of testing space is required, and the evaluation criteria are based on the inspector's feelings, resulting in variations in evaluation. Furthermore, even with the conventional method described in the third point, there is a problem that the evaluation criteria is based on the inspector's feeling, which causes variations in evaluation, and the inspection information is only one thing, namely kickback to the brake pedal. Therefore, there was a problem in that it was not possible to determine the operation of each wheel.

[0006]

[Means for Solving the Problems] The present invention has been made to advantageously solve the above-mentioned problems of the conventional method. A pseudo vehicle speed signal generating means for generating a pseudo vehicle speed signal that forcibly activates the system even if the system is lower than the operating vehicle speed;
When the tested vehicle is fully braked from a simulated driving state with the simulated vehicle speed signal input to the control unit of the anti-skid brake system on a medium-speed or low-speed brake tester, the brake tester outputs operation determining means for comparing the braking force value with a pre-input determination condition and determining that the anti-skid brake system has operated normally if the braking force value satisfies the determination condition; It is characterized by this.

[0007]

[Operation] In such a device, a vehicle to be tested is on a medium-speed or low-speed brake tester, and a pseudo vehicle speed signal generated by a pseudo vehicle speed signal generating means is input to the control unit of the anti-skid brake system. in,
When full braking is applied (the brake pedal is pressed hard) from a simulated driving state, the vehicle speed on the tester is usually 5 km/h, which is lower than the system operation minimum vehicle speed.
If the brake tester outputs a high braking force value, the anti-skid brake system will not operate even if the wheels lock, but since a pseudo vehicle speed signal is input here, the anti-skid brake system will not operate even if the wheels lock. If it is normal, it is activated and the brake fluid pressure on the wheel cylinder side is barely increased to prevent wheel slippage, and the brake tester shows that the brake fluid pressure is within a predetermined range, which is slightly higher than the rolling resistance value of the wheel. The power value will be output. Here, however, the operation determining means compares the braking force value outputted by the brake tester during the full braking with a determination condition inputted in advance including that the braking force value is within the predetermined range. If the determination conditions are met, it is determined that the anti-skid brake system has operated normally.

Therefore, according to the device of the present invention, it is possible to easily check the operation of the anti-skid brake system with equipment that is cheaper than equipment used in conventional methods, and since detection and judgment are performed using equipment, variations in evaluation can be reduced. This can be prevented from occurring, and furthermore, by using the braking force value for each wheel output by the brake tester, the operation of each wheel can be determined and the determination accuracy can be improved.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the anti-skid brake system operation confirmation device of the present invention, in which 4 is a medium-speed or low-speed brake tester;
is the vehicle to be inspected, 6 is a control unit for the anti-skid brake system installed in the vehicle 5, and 7 is a pseudo-vehicle speed signal that generates a pseudo vehicle speed signal that forcibly activates the anti-skid brake system even if the vehicle 5 is below the minimum operating speed of the anti-skid brake system. 8 is a connector connecting the pseudo vehicle speed signal generating device 7 and the control unit 6, and 9 is an arithmetic processing device as operation determining means.

The medium-speed or low-speed brake tester 4 here has basically the same configuration as the high-speed brake tester shown in FIG. It is inexpensive, and existing equipment can be used. Here, the brake tester 4 is provided for each of the left and right front wheels and the left and right rear wheel, and outputs a braking force value for each of the four wheels of the vehicle to be inspected 5. Further, the pseudo vehicle speed signal generating device 7 here generates a pulse signal similar to that outputted by a wheel rotation sensor mounted on a vehicle as the wheel rotates, using a normal pulse generation circuit, and converts the pulse signal into Based on the characteristics given in advance, the vehicle speed represented by the signal is changed over time as shown by curve S in FIG. 2, so that it gradually decreases in a sinusoidal manner similar to when the wheels are locked during braking.

[0011]The arithmetic processing device 9 here includes:
An arithmetic processing section 10 that performs arithmetic processing for analysis and judgment using a CPU, a storage section 11 that stores judgment conditions and judgment results using a storage medium such as a hard disk, and a keyboard 12 that allows the inspector to input data by key operation. and a display section 13 that displays the determination result by lighting a lamp.
, a print section 14 for printing out the determination results, and an inspection start button 15 for the inspector to instruct to start the inspection.

In such a device, the operation of the anti-skid brake system is checked in accordance with the procedure shown in the flowchart of FIG. That is, here, first, in step 21, the inspector boards the vehicle 5 to be inspected and
onto the brake tester 4 and connect the connector 8.
In the next step 22, the brake tester 4 is started to adjust the wheel speed of the tested vehicle 5 to a vehicle speed of about 5 km/h, which is lower than the system operation lower limit speed, and in the next step 23, the speed is At the stable point A in FIG. 2, the test start button 15 is pressed to instruct the arithmetic processing unit 9 to start the test, and in step 24, the pseudo vehicle speed signal generator 7 generates a pseudo signal representing the decreasing vehicle speed as shown by the curve S. A vehicle speed signal is input to the control unit 6 via the connector 8 to prompt the operation of the anti-skid brake system and cause the arithmetic processing unit 9 to start an inspection.In the following step 25, the brake pedal is strongly depressed from point B in FIG. The vehicle to be inspected 5 continues to be fully braked.

Due to this full braking, the brake master cylinder of the inspected vehicle 5 continues to generate the maximum brake fluid pressure, but
If the anti-skid brake system is normal, the system determines that the wheels are still locked based on the pseudo vehicle speed signal mentioned above and hardly increases the brake fluid pressure on the wheel cylinder side to prevent the wheels from slipping, so the brake tester 4 outputs a braking force value within a predetermined range that is slightly higher than the rolling resistance value of the wheel, as shown by line F in FIG. On the other hand, if the anti-skid brake system is not normal, the maximum brake fluid pressure from the brake master cylinder is transmitted to the wheel cylinder side, so the brake tester 4 will output a high braking force value.

Thereafter, in the next step 26, the arithmetic processing unit 9 inputs the braking force values of each wheel output from the brake tester 4 and analyzes the state of change in these braking force values, and then in the following step 27. Then, the analysis results are compared with the determination conditions to determine whether or not the anti-skid brake system operates properly. Specifically, for example, the inspector may input the judgment condition from the keyboard 12 by key operation in advance such that the braking force value is within a predetermined braking force value passing range until the pseudo vehicle speed indicated by the pseudo vehicle speed signal falls to the system operation lower limit speed. and that the braking force value will increase thereafter are input into the arithmetic processing unit 9 and stored in the storage unit 11, and the arithmetic processing unit 10 sets these judgment conditions at the beginning of the inspection. The braking force value of each wheel is read out and the following arithmetic processing is performed.

That is, as shown in FIG. 2, the arithmetic processing unit 10 analyzes the braking force value during the time T1 until the pseudo vehicle speed indicated by the pseudo vehicle speed signal drops to the system operation lower limit speed SL. The value of F is within the braking force value acceptable region between the braking force value a due to the rolling resistance of the wheels and the braking force value b which is the rolling resistance plus the braking amount due to a slight increase in brake fluid pressure (a < F ≦b), and for a short period of time T2 after point C when the pseudo vehicle speed decreased to the system operating lower limit speed SL, the system stopped operating and the value of the braking force F increased. A process of analyzing whether or not is performed is performed. As for the pass/fail judgment above, if the value of braking force F is a<F≦b during time T1 and increases during time T2, it is determined that the anti-skid brake system has operated normally. The test is determined to pass, and if not, it is determined that the anti-skid brake system did not operate or its operation was not normal, and the test is determined to fail.

In the subsequent step 28, the arithmetic processing unit 9 displays the result of the pass/fail judgment for each wheel by lighting the lamp on the display section 13, and if even one wheel fails, the overall judgment is made. The result is displayed as a failure, and the determination results are further stored in the storage unit 13. Then, in step 29, the inspector inputs an instruction to the arithmetic processing unit 9 from the keyboard 12 by operating keys as necessary, and the printing unit 14 prints out the determination result.

Therefore, according to the apparatus of this embodiment, it is possible to easily check the operation of the anti-skid brake system mounted on the vehicle to be inspected 5 with equipment that is cheaper than the equipment used in the conventional method. 4 to obtain the braking force value, and the arithmetic processing unit 9 makes a pass/fail judgment based on predetermined judgment conditions, so there is no variation in evaluation.Furthermore, since the braking force value is obtained for each wheel, the operation of each wheel is The determination accuracy can be improved.

Although the above has been explained based on the illustrated example, the present invention is not limited to the above-mentioned example. For example, the number of wheels for which the braking force value is calculated may be changed as appropriate depending on the configuration of the anti-skid brake system. In addition, the configuration of the operation determining means can be changed as necessary.

[0019]

[Effects of the Invention] Thus, the anti-skid brake system operation confirmation device of the present invention uses a medium-speed or low-speed brake tester that is relatively inexpensive and can be used with existing equipment, compared to equipment used in conventional methods. It is possible to easily check the operation of the anti-skid brake system using inexpensive equipment, and since the detection and judgment are performed using equipment, it is possible to prevent variations in evaluation. By using the braking force value, the operation of each wheel can be determined and the determination accuracy can be improved.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of an operation confirmation device for an anti-skid brake system according to the present invention.

FIG. 2 is a characteristic diagram showing changes in pseudo vehicle speed and braking force values in the device of the above embodiment.

FIG. 3 is a flowchart showing the operating procedure of the apparatus of the above embodiment.

FIG. 4 is a plan view showing a high-speed brake tester used in a conventional operation confirmation method.

FIG. 5 is an explanatory diagram showing a normal operation determination method in the conventional operation confirmation method.

FIG. 6 is a schematic diagram showing a free roller tester used in another conventional operation confirmation method together with a vehicle to be inspected.

[Explanation of symbols]

3 Free roller tester 4 Medium speed or low speed brake tester 5 Tested vehicle 6 Control unit 7 Pseudo vehicle speed signal generator 9 Arithmetic processing unit

Claims (1)

[Claims] [Claim 1] A pseudo vehicle speed signal generating means (7) for generating a pseudo vehicle speed signal that forcibly activates the anti-skid brake system even if the vehicle is below the operating lower limit vehicle speed of the anti-skid brake system; When the vehicle under test is fully braked from a simulated running state with the simulated vehicle speed signal input to the control unit of the anti-skid brake system, the braking force value output by the brake tester is determined by inputting the brake force value input in advance. an operation determination means (9) for determining that the anti-skid brake system has operated normally if the braking force value satisfies the determination condition by comparison with the determination condition; Operation confirmation device.