JP2961887B2 - Inspection method for braking force of vehicle equipped with anti-lock control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for testing a braking force of an automobile having an anti-lock control device for a vehicle.

[Conventional technology]

It is necessary to inspect whether the anti-lock control device operates properly before the vehicle equipped with the anti-lock control device for in-vehicle use is assembled and shipped or during a periodic inspection. This is because the anti-lock control device is a device for efficiently controlling the automobile brake, and due to its nature, a sufficient inspection is required to ensure safety.

Inspection of such an anti-lock control device generally includes checking that a signal system sent from a wheel speed sensor is correctly sent to an anti-lock control circuit (hereinafter referred to as an ABS control circuit), and that a predetermined braking force is applied. A braking force test is performed to determine whether or not the braking force can be obtained.

The inspection device used for this inspection was equipped with a meter for measuring a braking torque in a wheel drive unit including a rotating roller that abuts a front wheel or a rear wheel of an automobile to rotate these wheels and a drive motor for rotating the roller. A brake tester,
An inspection unit is connected via a check terminal provided in the ABS control circuit to check whether a wheel speed signal sent from the wheel speed sensor to the ABS control circuit is abnormal and to control the operation of the brake tester.

In the conventional method of performing a braking force inspection with the above inspection device,
The ignition roller is turned on, the power is turned on, the rotating roller is started, and when the rotation reaches a certain rotational speed, the brake is stepped on to start a braking force inspection.

While the brake is being depressed, a control signal is sent from the inspection unit to the solenoid valve via the ABS control circuit. This control signal is transmitted in a fixed pattern according to a program pre-installed in the electronic control circuit of the inspection unit.

This signal pattern is such that, for example, when the ABS is a three-position control, signals of pressure reduction, holding, and pressure are transmitted at predetermined intervals. In the case of the two-position control, a pattern in which pressure reduction and pressure signals are sent at predetermined intervals is used.

When a control signal having such a pattern is sent, the braking force changes in spite of the braking force, and the change in the braking force is detected by a brake tester, and the detection signal is sent to the inspection unit to be controlled. It is determined whether the power change is normal. The judgment in the inspection unit is conventionally based on the absolute value of the braking force.

[Problems to be solved by the invention]

However, in the above-described conventional braking force inspection, a signal corresponding to the absolute value of the braking force is sent to the inspection unit, and whether or not the braking force is normal is determined based on the signal. It changes greatly depending on the treading force when stepping on. When the brake pedal is first strongly depressed, the depressurized value and the pressurized value greatly fluctuate, and when it is weak, the fluctuations become small.

Therefore, in order to determine that the braking force is normal even if the pedaling force is large, the range of the determination criterion must be increased and a looser reference must be set, and in some cases, the braking force is insufficient. Nevertheless, there is a possibility that a defective product that passes the test may occur.

Conventionally, as a method for preventing such a misjudgment of judgment from occurring, the inspector only has to strictly set the conditions of the stepping force on the brake, so that the inspection requires skill, and as a result, the work efficiency is not improved. There were also problems.

The present invention has been made in view of the current situation of a conventional braking force inspection method for an automobile equipped with the above-described antilock control device. To provide a braking force inspection method capable of detecting a change in the braking force and performing a braking force inspection based on whether the ratio of the braking force is within a predetermined range, making an accurate pass / fail judgment and improving work efficiency. It is in.

[Means for Solving the Problems] In the present invention as means for solving the above problems,
In a stopped state, a rotating roller abuts on a wheel of an automobile equipped with an anti-lock control device to drive the rotating roller to rotate the wheel, apply a brake to the wheel, and apply an anti-lock control device during the load. On the other hand, control signals for pressure reduction, holding, and pressure are sent from the outside in a predetermined pattern to control the operation of the control valve of the antilock control device, and a change in the obtained braking force is detected via a rotating roller. The ratio of the braking force before and after the pressure reduction and the ratio of the braking force after the pressure reduction and the pressure after the pressure holding are determined, and it is determined whether or not each ratio is within a predetermined range. The power inspection method was adopted.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a view showing a state where an automobile is set in an inspection apparatus for carrying out a braking force inspection method according to the present invention.

Automotive ABS control circuit 10 for automatic brake control
It has. The ABS control circuit 10 comprises a microcomputer, and as shown in FIG.
11, central processing unit (CPU) 12, storage unit 13, drive circuit 1
4. It has check terminals 15 and so on. When the vehicle is running, when the brake is depressed, the wheel speed and the like are calculated in the CPU 12 based on the wheel speed signal from the wheel speed sensor S, and the opening and closing of the solenoid valve V as an actuator is controlled via the drive circuit 14.

An inspection device for inspecting the operation of the ABS control circuit 10 includes an inspection unit and a brake tester 30.
Reference numeral 20 is connected to the ABS control circuit 10 via the check terminal 15.

The inspection unit 20 includes a connection terminal 21, a relay unit 22, an interface unit 23, sequencers 24 and 25, and the like. A brake tester 30 is connected to the sequencers 24 and 25. The brake tester 30 detects a motor 31, a rotating roller 32 driven by the motor 31, a braking force meter 33 for measuring a brake braking force, and the presence or absence of a wheel. Photoelectric switch
It has 34 mag.

FIG. 3 is a block diagram showing the configuration of the interface unit 23. As shown, the interface unit 23
Are the input / output terminals 15'a, 15'b, the interface circuit 23
1, 231 ', a microcomputer 232, interface circuits 233 and 234, and the like.

The microcomputer 232 contains a program for instructing a control signal for the braking force inspection according to the present invention, and the like. When a serial signal sent from the ABS control circuit 10 is received through the input terminal 15'a, a control signal for inspection of a predetermined pattern is sent from the microcomputer 232 to the ABS control circuit 10 through the output terminal 15'b.

Further, in the sequencer 24, a calculation unit for obtaining a value and a ratio of the braking force from a signal representing the braking force detected by the brake tester 30 and a determination unit for determining whether these values and the ratio are within a predetermined range. It is included.

The braking force inspection is performed by the inspection device as described above as follows.

Connect the inspection device as shown in FIG.
Put the front wheel (or rear wheel) on the Ignition IGN is turned on, ABS control circuit 10 is started, and the power of the inspection device is turned on.
Then, the motor 31 of the brake tester 30 is driven, and the rotating roller 32 is rotated to set the simulated traveling state.

When the brake pedal is depressed, the anti-lock control is started. In this case, the anti-lock control is
The mode is set by a serial signal sent to the inspection unit 20 when the IGN is turned on, which is performed by a control signal according to a program of the interface unit 23.

The control signal of a predetermined pattern by the program of the interface unit 23 generates a pressure reduction command, a holding command, and a pressurization command in a predetermined pattern within a predetermined time, and the change in the braking force due to this is shown in FIG. Signal.

When the braking force changes according to the control signal, the change in the braking force is detected by the braking force meter 33 and sent to the sequencer 24 as an electric signal.

In the sequencer, the arithmetic unit calculates the absolute values of the braking forces X, Y, and Z shown in the figure from the signals. The ratio of Y / X and Z / Y is determined from the value of the obtained braking force.

Next, the determination unit determines the braking state by comparing the value of the braking force value and the value of the ratio with a reference value.

For example, if the determination value is within the range of 20% <Y / X <80% 105% <Z / Y <350%, it is determined that the braking force is normal. If it is out of any of the above ranges, it will be rejected as abnormal braking force.

The above-described inspection is performed for each wheel such as a front right wheel, a front left wheel, a rear right wheel, and a rear left wheel.

After the braking force test, release the brake pedal,
The operation of the signal system of the wheel speed sensor and other switches are inspected.

〔effect〕

As described in detail above, the braking force inspection method according to the present invention detects a change in the braking force controlled by the anti-lock control device capable of reducing, holding, and increasing the braking force, and detects the ratio of the braking force before and after the pressure reduction. It is determined whether the ratio of the braking force held after depressurization and after pressurization is within a predetermined range to check whether the braking force is normal. Even if they are different, it is possible to correctly judge the inspection result, and the advantage is obtained that the inspection work efficiency is improved.

[Brief description of the drawings]

FIG. 1 is an overall schematic block diagram of an inspection apparatus for implementing a braking force inspection method according to the present invention, FIG. 2 is a schematic block diagram of an ABS control circuit, FIG. 3 is a schematic block diagram of an interface unit, FIG. FIG. 7 is a diagram for explaining a change in braking force due to a pressure reduction, holding, and pressure command. 10: ABS control circuit, 15: Check terminal, 20: Inspection unit, 23: Interface unit, 30: Brake tester, 32: Rotating roller, 33: Brake force meter, S: Wheel speed sensor , V ... Solenoid valve.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01M 17/00-17/007 B60T 8/88

Claims (1)

(57) [Claims] An anti-lock control device is mounted on a wheel of a motor vehicle, in a stopped state, a rotating roller is brought into contact with the wheel to drive the rotating roller, thereby rotating the wheel, and applying a brake to the wheel. A control signal of pressure reduction, holding, and pressure is sent from the outside to the antilock control device in a predetermined pattern to control the operation of the control valve of the antilock control device. The ratio of the braking force before and after the pressure reduction and the ratio of the braking force after the pressure reduction and the pressure after the pressure holding are determined through the detection through the control unit, and it is determined whether each ratio is within a predetermined range. A method for testing the braking force of a vehicle equipped with an anti-lock control device.