JPH04198836A - Brake tester - Google Patents

Abstract

PURPOSE:To miniaturize a brake tester, precisely judge and measure the function of a wheel equipped with an antiskid brake by providing an arbitrary roller so that the torque thereof can be set so as be lower than that of other roller. CONSTITUTION:When a signal lowering the transmission torque to an arbitrary wheel 5 or one of rollers 6 by required quantity is inputted to a controller, the driving force of a drive means 10 is controlled by a torque control apparatus 11 so as to be lowered and the driving force of the predetermined roller 6 is lowered and the wheel 5 on said roller is decelerated to show the omen of lock. This state is detected by the car speed sensor of an ABS control apparatus and the correction operation weakening the braking force of the wheel 5 is performed. Subsequently, when the speed of the wheel 5 is recovered, the correction operation increasing braking force is performed. By this method, precise measurement can be performed.

Description

[Detailed Description of the Invention] (Industrial Application Field) In addition to measuring the maximum braking force, the present invention makes it possible to easily and accurately determine the function of a vehicle equipped with anti-skid brakes (hereinafter referred to as an ABS vehicle). Regarding brake testers.

(Prior Art) In recent years, a large number of ABS vehicles have been produced that improve running stability during sudden braking, and there is a demand in the market for a brake tester with ABS function determination as a braking force testing device for these vehicles. ing.

Conventionally, this type of brake tester, as disclosed in Japanese Patent Application Laid-Open No. 1-148649, includes a roller on which the tires of a test vehicle are placed, a motor that drives the roller, and a load between the tire and the roller during braking. Some vehicles are equipped with a detector that detects fluctuations, and after the tires are rotated at high speed, the brakes are operated and the braking condition of the vehicle is measured by the detector.

However, this method requires a high-speed, high-output motor, and has the problem of not being able to perform measurements under road conditions with a low coefficient of friction, where ABS vehicles perform their original function.

For this reason, the applicant formed a horizontal flat on one side of the circumferential surface of the roller to provide a high friction coefficient part, and formed the other side circumferential surface to be a smooth surface to provide a low friction coefficient part, and measured the maximum braking force. Sometimes the tire is placed on a high friction coefficient area and the rollers are rotated at a relatively low speed, while when ABS83 functions, the tire is transferred to a low friction coefficient area and the roller is rotated at a relatively high speed to achieve the above intended purpose. We have developed a brake tester that achieves
The application is filed as No. 8.

(Problem to be solved by the invention) However, in the tester of this application, as a result of providing two types of friction coefficient parts on the circumferential surface of the roller, the roller becomes long and the tester becomes large accordingly. Since the space between the rollers is restricted, there is a problem in that it becomes difficult to install bits required for inspecting and adjusting the underside of a vehicle during measurement, for example.

In addition, in the above tester, when the ABS83 function is activated, all four wheels of the test vehicle are placed on a low friction coefficient area, so the wheels to be locked are determined by heteronomous conditions such as tire wear and ground contact area, and are not specified. The ABS function could not be determined based on the wheels.

Therefore, even if the tester determines that the ABS function has failed, it is not possible to identify the adjustment or repair points as in the past, so it is impossible to identify the parts that are to be adjusted or repaired. It was unreasonable to be forced to replace related parts.

The present invention solves these problems and makes it possible to miniaturize this type of tester and perform maintenance inspections on the underside of the test vehicle during measurement, as well as enable the ABS83 function for specific wheels, making it possible to perform this type of measurement. The purpose is to provide a brake tester that allows accurate testing.

(Means for Solving the Problems) Therefore, the brake tester of the present invention includes a roller having a high friction peripheral surface on which a wheel can be placed, a driving means capable of driving the roller, and a braking force of the roller. A plurality of brake tester units each having a detectable braking force detecting means and a signal inputted from the braking force detecting means are stored and calculated, and based on a pre-stored judgment value using this information as a condition, brake test is performed. In a brake tester that has a controller that determines the pass/fail of power, the torque of a predetermined roller can be set to be lower than the torque of other rollers. It is characterized in that it enables maintenance inspection and enables the <ABS83 function based on a specific wheel, so that this type of measurement can be performed precisely.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. In Figs. 1 to 3, 1 is a test space provided on the floor of an automobile repair shop, etc., and a vertically long bit 2 is placed in the center of the test space. A brake tester unit 3.3 for the front wheels and a brake tester unit 4.4 for the rear wheels are installed on both sides of the bit 2.

The brake tester unit 3.4 has substantially the same structure, and includes a pair of rollers 6 on which wheels 5 of a test vehicle (not shown) can be placed on a circumferential surface with a groove formed therein;
A transmission means 7 such as a chain and a sprocket disposed between the rollers 6.6, a wheel boarding lift 8 disposed between the rollers 6.6, and a load cell capable of inputting a signal to a controller to be described later. It is equipped with a braking force detection means 9 such as the above.

Further, the brake tester unit 3.4 includes a drive means IO such as a torque-controllable motor that is ON/OFF controlled by the controller, and a torque that can variably control the torque of the drive means 10 by a control signal from the controller. It has a control device 11 and a transmission means 12 such as a bobbin and a belt disposed between the drive means 10 and the one roller 6.

The brake tester unit 4 on the rear wheel side is mounted on a mount 13.
The pedestal 13 is movable along a pair of guide rails 14 arranged in the longitudinal direction of the test vehicle, and has a connecting block (not shown) on the back surface of which can be screwed into a screw shaft 15. has been established.

One end of the screw shaft 15 is connected to a wheelbase adjustment motor 16, which is installed between the brake tester units 3.4 and whose operation is controlled by a controller 17.

The controller 17 has a built-in microcomputer, for example, and inputs the model information of the test vehicle, the maximum braking force signal from the braking force detecting means 9, and the braking force signal from the braking force detecting means 9 when the ABS83 is functioning. , the number of passing times nu, n1, that is, the number of times the braking force that changes moment by moment with - times of brake operation passes the upper and lower reference limits f, J, fL, and from the computer, the driving means 10 It is possible to output ON/OFF signals for each torque control device II, control signals for each torque control device II, and ON-OFF signals for the wheel base adjustment motor 16 and wheel boarding lift 8.

On the other hand, the computer contains the wheelbase for each vehicle type, braking force judgment values of the sum and difference of the left and right braking forces of the front and rear axles, and the upper and lower limit reference values fu, fL of the braking force when the ABS83 function is activated. The number of times N, j, and N of passing the reference are stored.

Then, the computer calculates the sum and difference between the front axle and the rear axle based on the input maximum braking force signal, and compares the calculated value with the braking force determination value to determine whether the result is acceptable. At the same time, the number of passing times nLI+nL when the ABS83 is functioning is compared with the reference number of passing times NU and NL to determine whether the result is pass or fail, and these judgment signals can be output to the display lamp 19 of the display panel 18. .

FIG. 4 shows another embodiment of the invention, in which the same reference numerals are used for corresponding components as in the previous embodiment.

In this embodiment, the torque control device 1
1, instead of variably controlling the driving force of the driving means 10, the test wheel is controlled by using a clutch device 20 that connects and disconnects the driving force of the driving means 10, and a clutch control device 21 that controls the operation of the device 20. It is characterized in that the drive of the mounted roller 6 is cut off or the roller 6 is placed in a semi-connected state, thereby simplifying the torque control described above.

(Function) The brake tester configured in this manner can measure the maximum braking force and determine the ABS function as described later using the roller 6 having grooves on the circumferential surface, similar to known testers, so it can be divided into two types. Compared to a roller that requires a roller with a friction coefficient of
．． Since a large space can be secured between the pits 6 and 6, a pit 2 large enough for the worker to enter can be provided in the area.

Therefore, during a series of measurements to be described later, the operator
By entering the vehicle, it becomes possible to perform maintenance and inspection work on the underside of the test vehicle.

Next, when measuring the maximum braking force using the above tester, it is carried out in the same manner as in the conventional method.

That is, the model of the test vehicle, for example, an ABS vehicle, is registered in advance in the controller 17, and when the model is registered,
The controller 17 provides the wheel base of the climbing vehicle, the upper and lower limit values of the braking force of each wheel 5, the braking force judgment value of the sum and difference of the left and right braking forces of the front and rear axles, and the ABS function judgment test. The upper and lower limit reference values fU and fL of the braking force and the number of times Nu and NL of passing the reference are read out, and based on the wheel base information of these, the wheel base adjustment motor 16.
A control signal is output to 16.

For this reason, the motors 16, 16 are driven, and the power thereof is transmitted via the screw shaft 15.15 to the pedestal 13.13, which constitutes a screw mechanism together with the pedestal 13.15.
13 moves along guide rails 14.degree. 14 and stops at a position commensurate with a predetermined wheel base.

After adjusting the center distance of the front and rear rollers 6.6 to the wheel base, the test vehicle is moved to the brake tester units 3, 4, and its wheels 5 are placed on the tire loading lift 8.

Thereafter, the lift 8 is lowered to place each wheel 5 on a pair of rollers 6.6, and when the lift 8 is lowered to a predetermined position, the driving means 10 for each roller 6 is lowered.
to drive.

The power of the drive means 10 is transmitted via the transmission means 12.7 to the roller 6.6, and the rotation of the roller 6.6 causes the wheels 5 on the roller 6.6 to rotate.

Under such circumstances, when the driver of the test vehicle depresses the brake pedal, the braking force of each wheel 5 is input to the controller 17 via the braking force detection means 9. The controller 17 calculates the sum and difference of the braking force values of the front axle and the rear axle, compares the calculated value with a judgment value, and outputs a pass/fail judgment signal to the display lamp 19 of the display board 18.

In other words, if the total braking force and the sum of the rear axle are both greater than or equal to the judgment value, and both the difference between the front axle and the difference between the rear axle are less than or equal to the judgment value, the pass indicator lamp 19 lights up, and if the above conditions are not met. , the failure indicator lamp I9 lights up.

Next, when performing ABS function determination, torque control device 1
1, the driving force of the driving means 10 is adjusted to an extent that overcomes the braking force described below, and under such circumstances, the roller 6
is rotated to rotate the wheels 5, and the driver is made to operate the brake pedal to apply a --like braking force to each wheel 5.

Therefore, in this case, there is no need to change the position of the wheel 5 on the roller 6 for maximum braking force measurement and ABS function determination, so these measurements can be easily performed.

Under such conditions, a signal is input to the controller 17 to reduce the driving force of the drive means 10 for any wheel 5 or -axis, that is, the torque transmitted to the roller 6, by a required amount.

In this way, the signal is inputted from the controller 17 to a predetermined torque control device 11, and the driving force of the single or plural driving means 10 is adjusted to decrease by the device II. Then, this adjusted driving force is transmitted to the transmission means 12.
9 to a predetermined roller 6.
Since the driving force is weak, the wheels 5 on the rollers 6 rotate at a reduced speed.

In this way, when a predetermined wheel 5 forms a sign of locking, such a situation is detected by the vehicle speed sensor (as shown) of the ABS control device mounted on the test vehicle, and as soon as the wheel 5 is about to lock, the corresponding wheel is Perform the corrective action to weaken the braking force in Step 5.

Then, as the braking force is weakened, the rotational speed of the wheel 5 recovers, and if the ABS control device determines that it is not locked, a corrective action is performed to strengthen the braking force of the wheel 5.

This repeated operation of braking force by the ABS control device is
As shown in Fig. 3, braking is performed repeatedly at high speed during one braking operation, and the locus drawn by this braking force value is the upper and lower limit reference value fu,
ft, is counted by a counter circuit built into the controller 17, and the number of times it passes is n u+ n
L is compared with the reference passing times NU and NL to determine pass/fail, and the determination signal is output to the display lamp 19 of the display panel 18.

In this way, in the present invention, when braking the wheels 5,
By reducing the driving force of the wheel 5, the wheel 5 is decelerated as quickly as possible to activate the ABS control device of the test vehicle. This system utilizes the principle that when the wheels of a vehicle are placed on a road surface with a low coefficient of friction and the brakes are applied, they lose grip on the road surface and rapidly decelerate.
This is in line with the original function of the ABS control device.

Therefore, in the present invention, the ABS function can be determined based on a specific wheel 5, which eliminates the conventional problem of determining the locked wheel based on heteronomous conditions, and makes this type of determination more precise. The reliability of the judgment results can be increased.

In addition, with the above configuration, it is possible to check the operation of the vehicle speed sensor that makes up the ABS control device, the valves inserted in the brake hydraulic circuit, etc. for each wheel, so even if the ABS control device breaks down, However, by being able to identify the defective location and perform repairs and inspections accordingly, accurate and rational maintenance becomes possible.

(Effects of the Invention) As described above, since the brake tester of the present invention is provided with a roller having a high-friction peripheral surface on which a wheel can be placed, the brake tester of the present invention requires a roller having two types of friction coefficient parts on the peripheral surface. In comparison, this type of tester can be made smaller and lighter, and by securing a wide space between the coaxially arranged rollers, it is possible to install a bit, for example, in this space, and the pit can be used to make measurements easier. Can perform maintenance inspections on the underbody of the test vehicle.

Further, since the present invention allows the torque of a predetermined roller to be lower than the torque of other rollers, it is possible to determine the ABS function based on a specific wheel, and this type of measurement can be performed precisely. Since the ABS control device mounted on the test vehicle can be checked for each individual wheel, the failure location of the control device can be identified, and its repair inspection and maintenance can be carried out accurately and rationally.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing one embodiment of the present invention, and Fig. 2 is a plan view showing an embodiment of the present invention.
FIG. 3 is a characteristic diagram showing changes in braking force during ABS function determination, and FIG. 4 is a block diagram showing important parts of another embodiment of the present invention. 3.4... Brake tester unit 5... Wheels,
6 - Roller 9... - Braking force detection means, 10 - Drive means 17... Controller

Claims (1)

[Claims] A plurality of brake tester units comprising a roller having a high friction peripheral surface on which a wheel can be placed, a driving means capable of driving the roller, and a braking force detecting means capable of detecting the braking force of the roller; A brake tester is equipped with a controller that stores and calculates the signal input from the braking force detection means, and determines whether the braking force is acceptable or not based on pre-stored judgment values using this information as conditions. , a brake tester characterized by being able to lower the torque than other rollers.