JPH0799347B2 - Automatic braking force measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an automatic braking force measuring device, and in particular, to a four-wheel vehicle running on rollers that rotate at a constant speed, and braking forces of various brakes incorporated in the vehicle. The present invention relates to the configuration of a device for performing a test.

[Prior Art] A braking force measuring device (brake tester) in which a roller that rotates at a constant speed is provided for each of four wheels is well known, and this device is provided on the front left and right wheels and the rear wheel of the vehicle. The braking force of the four left and right wheels is measured at the same time, and a brake inspection is performed on all the completed vehicles at the time of shipment.

For example, when an inspector rides a vehicle on the roller of the braking force measuring device, the measuring device is activated, but the inspector operates the main brake and the parking brake in this order, and the inspector displays them on the display panel of the measuring device. Visually check the braking force of the four wheels. When the main brake is operated, the sum and difference of the left and right wheels of the front and rear wheels are within the specifications of the main brake, or when the parking brake is operated, the sum of the left and right wheels of the rear wheels only. And the inspector himself judged whether the difference was within the specifications of the parking brake.

[Problems to be Solved by the Invention] However, in recent years, the number of brake specifications has increased due to an increase in vehicle types, and the inspection time has been shortened due to an increase in the number of vehicles produced. It is impossible to raise the efficiency of production by the method of checking the braking force display and calculating in the head to determine whether or not it meets the standard.

Therefore, it has been proposed to automate the braking force measurement, and an example thereof is shown in Japanese Utility Model Laid-Open No. 58-86543.

However, in this case, the order of the braking force measurement is determined in advance, and it is necessary to operate in the order of the main brake and the parking brake, and the measurement cannot be performed if the inspector makes an operation error.

It is also possible to distinguish between main brake measurement and parking brake measurement by the selection switch without deciding the order of measurement, but it requires extra man-hours to activate the selection switch, and Mistakes in selection also occur.

In this way, if it is left to the inspector to decide whether the measurement target is the main brake or the parking brake, it will be difficult to perform an efficient inspection because human malfunction will increase. become.

OBJECT OF THE INVENTION The present invention has been made in view of the above conventional problems,
An object of the invention is to provide an automatic braking force measuring device capable of automatically determining the type of a brake to be measured and efficiently performing an inspection.

[Means for Solving the Problems] In order to achieve the above object, the present invention measures the braking force applied to each wheel by various brakes by running a four-wheel vehicle on rollers that rotate at a constant speed. The automatic braking force measuring device for displaying the result is characterized in that a brake type determining means is provided and the type of the brake to be measured is automatically determined.

The brake type determination means compares the measured value of the braking force of the main brake wheels excluding the parking brake wheels with a predetermined value and determines that the main brake is in the operating state when the measured value is larger than the predetermined value.

That is, for example, in a vehicle in which the wheels on which the brakes are operated are different so that the braking force of four wheels is generated by the operation of the main brake and the braking force of the two wheels is generated by the operation of the parking brake,
It is designed so that the type of brake currently measured can be automatically determined even if the inspector does not specify it.

[Operation] According to the configuration described above, in the actual measurement of the braking force, first, when the roller of the measuring device rotates at a constant speed, the braking force of the brake exerts a force opposite to the rotating direction on the roller. This force is measured for each individual wheel by measuring means such as a load cell that is integrated with the roller.

First, since the braking force is exerted only on the other two wheels by the main brake, if the measured value of the braking force on the other two wheels is larger than the first predetermined value in the primary determination, the main brake is activated. It is understood that it is in a state. Next, even when the measured value of the braking force of the other two wheels is smaller than the first predetermined value, the sum of the measured values of the braking force of the other two wheels is further determined by the predetermined difference in the secondary determination. When it is larger than the sum of the measured values of the braking forces of the other two wheels, it is determined that the auxiliary brake is in the operating state. Therefore, even if the measured value of the braking force of the other two wheels becomes smaller than the first predetermined value due to the failure of the other two wheels in the primary determination, the secondary determination is performed to detect this failure state as the auxiliary brake. It is possible to more reliably determine the operating state of the main brake and the operating state of the sub brake without being confused with the operating state of.

Generally, in a main brake of a four-wheel vehicle, when a failure occurs in a brake system of the front wheels as the other two wheels of the four wheels, for example, a situation may occur in which only the braking force of the front wheels decreases. is there. At this time, even if the main brake is actually operating, the primary determination may be determined to be the sub-brake operating state, not the main brake operating state. Even in such a case, in the secondary determination, by comparing the sum of the measured values of the braking forces of the two wheels with the sum of the measured values of the braking forces of the other two wheels,
Is the braking force of the other two wheels reduced due to a failure?
Since the sub-brake is in the operating state, it is possible to easily identify whether the braking force of the other two wheels has decreased.

In this way, the type of brake is automatically determined from the measured braking force of each wheel, and based on this determination, it is measured whether the braking force of each brake meets the respective brake standard. The pass / fail of the measured value and the standard value is displayed on a display or the like.

[Embodiment] A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of an automatic braking force measuring device according to the present invention, and FIG. 2 shows a detailed configuration inside thereof.

In FIG. 1, a four-wheel vehicle 10 is mounted on a roller 12, which is controlled so as to rotate at a constant speed, which will be described later. A measuring means 20 is connected to the roller 12, and the roller 12 is activated by the braking operation.
The braking force applied to is measured, and the measured value is subjected to various calculations by the calculating means 22 (microcomputer or the like) to determine whether the braking force conforms to the standard.

Brake type determining means 24, which is a characteristic feature of the present invention
Is incorporated in the calculating means 22, and the calculation result obtained by the calculating means 22 is displayed on the display device 26.

In addition, the brake test is performed on various vehicles 10,
Since the standard value of the braking force also differs depending on the type of vehicle, a vehicle type selection switch 28 for selecting the vehicle type before measurement is provided. In the vehicle of the embodiment, the braking force acts on the four front and rear wheels by the brake pedal 10a as the main brake, and the braking force acts on the two rear wheels by the parking brake 10b as the sub brake.

The detailed contents of such a structure are shown in FIG.

That is, four rollers 12-corresponding to four wheels
1 to 12-4 are driven by motors 14-1 to 14-4, which are controlled by constant speed controllers 16-1 to 16-4, which rotate the roller 14 by the constant speed controller 16. The speed is kept constant regardless of the load applied to the roller 14.
The load (braking force) applied to the roller 12 by the four wheels is detected by load cells 18-1 to 18-4 as sensors, and the output of the load cell 18 is supplied to the measuring means 20.

This measuring means 20 comprises a load cell amplifier 20a and an A / D converter 20.
The detection signal which is composed of b and is an analog signal output from the load cell 18 is amplified by the load cell amplifier 20a at a predetermined amplification factor, and this detection signal is subsequently converted into a digital signal by the A / D converter 20b. .

The calculation means 22 is composed of a CPU (central processing unit) 22a and a memory 22b in which the brake type determination means 24 is incorporated, stores the measurement results output from the measurement means 20, or determines the measurement target from these measurement results. The type of the brake is judged, the braking force is calculated based on the judgment result, and the calculation for judging whether this braking force matches the standard value of the brake is performed, and the calculation result is also stored. . Therefore, the standard value of the main brake, the parking brake, and the determination value for determining whether the braking forces of these brakes are acceptable or not are input to the memory 22b, and the stored information of the memory 22b read by the vehicle type selection switch 26 is stored in the memory 22b. Based on this, the calculation is performed.

A feature of the present invention is that the device can automatically determine which brake is operated from the detection signal obtained by the load cell 18, and the brake type determination means 24 is for the parking brake. Measure the braking force of the front wheels, which are the wheels for the main brake, excluding the rear wheels, which are the first wheels.
The first predetermined value is 1/4 (Y) of the specified value of the front wheel sum (braking force), and the measured value of the front wheel sum (X) is the first predetermined value. Compare with Y. When the measured value X of the sum of the front wheels is larger than the first predetermined value Y, it means that the braking force of the main brake is acting on the front wheels, and thus the primary determination is made that the main brake is in the operating state. If it is smaller than the main brake, it is determined that the parking brake is operating in this case.

In the embodiment, when it is determined that the parking brake is in the operating state in the primary determination, the rear wheel sum measurement value (denoted as A) of the parking brake wheel (rear wheel) is used to ensure this determination. Is compared with 1/4 of the rear wheel sum prescribed value as the second predetermined value (B), and in the case of the parking brake, the braking force difference between the front and rear wheels should be large, so the measured value of the front wheel sum X And whether the difference between the measured rear wheel sum A and the measured value A is larger than 10 kg. Therefore, when the measured value A of the rear wheel sum is larger than the second predetermined value B and the difference between the measured value X of the front wheel sum and the measured value A of the rear wheel sum is larger than 10 kg, the parking brake is measured. It is secondarily judged that there is.

If the difference is smaller than 10 kg, it means that there is no difference in the braking force between the front and rear wheels, and thus it is determined that the main brake is measured. In this case, the measured value of the rear wheel sum A
If is smaller than the second predetermined value B, nothing is done because there is a possibility that the brake is not operating or there is a failure in detection.

In this way, when the type of brake is determined, calculation processing is performed on the load of the wheel being braked by the brake, and finally it is determined whether the braking force of this brake is acceptable or not. Will be.

The results of these brake braking force tests are displayed on the display device 26, and as shown in FIG. 2, the numerical display 26a displays the measured values (load values) of the front and rear wheels and the difference between the front and rear wheels. However, the display lamp 26b displays the pass / fail of the measured values of the front and rear wheels and the difference between the front and rear wheels, the display lamp 26c displays the pass / fail of the parking brake, and the display lamp 26d displays the pass / fail of the overall braking results. It

The embodiment has the above-mentioned structure, and its operation will be described below with reference to FIGS.

First, when the vehicle 10 is set at a predetermined position on the roller 12 of the measuring device, the vehicle type is selected by the vehicle type selection switch 28. When the start switch provided in the vehicle type selection switch 28 is turned on, the roller 12 rotates at a constant speed. In this state, when the inspector actuates either the brake pedal 10a or the parking brake 10b of the vehicle 10, the load applied by each wheel is detected by the load cell 18, and the detection signal is calculated by the measuring means 20 through the calculating means. Supplied to 22.

Then, the calculation means 22 including the brake type determination means 24
As shown in Fig. 3, when the measurement starts,
At step 101, it is first determined whether or not the measured value (X) of the sum of front wheels is larger than 1/4 (Y) of the specified value of the sum of front wheels, and X ≧
When Y, it is determined that the main brake is in the operating state, the process proceeds to step 104, the braking force of the main brake is measured (Table 1), and when X <Y, it is determined that the operating state is other than the main brake. Then, the process proceeds to step 102.

In this step 102, it is judged whether or not the measured value of the rear wheel sum (A) is larger than 1/4 (B) of the rear wheel sum prescribed value, and A <
If it is B, the process proceeds to step 107 and does nothing,
When A ≧ B, the routine proceeds to step 103, where it is secondarily judged whether the difference between the measured value X of the front wheel sum and the measured value A of the rear wheel sum is larger than 10 kg. And (AX) ≧ 10kg
When it is, it is determined that the parking brake is in the operating state, the process proceeds to step 106 (Table 3) and the braking force is measured. When (AX) <10 kg, there is no difference in the braking force between the front and rear wheels. Therefore, it is determined that the main brake is measured, and the process proceeds to step 105 (Table 1).

The operations of the tables 1 and 3 in steps 104 to 106 are shown in FIG. 4, and the table 1 for measuring the braking force of the main brake is, as shown in FIG. 4 (A),
In step 201, the braking force of the four wheels is measured, whether or not the measured values of the front wheel sum and the rear wheel sum match the standard values, and the measured values of the front wheel left-right difference and the rear wheel left-right difference are set to the standard values. It is determined whether or not they match, and in the next step 202, a total determination is made as to whether or not the braking force of the main brake matches the specified value.

Further, as shown in FIG. 4 (B), the table 3 for measuring the parking brake determines whether or not the measured value of the rear wheel sum matches the specified value as the parking measurement in step 301. Then, it is determined whether or not the measured value of the rear wheel left-right difference matches the standard value, and in the next step 302, a total determination whether the measured value of the braking force of the parking brake matches the specified value. Is done. And these tables 1
And when the table 3 is completed, the process proceeds to the next step 108 in FIG.

In this step 108, it is judged whether or not the pass / fail judgment for the main brake has been completed, and the next step 10
In step 9, it is judged whether or not the parking brake has been passed or failed. If both are "YES", step 11
At 0, a comprehensive judgment is made on the braking force of the measurement vehicle.

In this way, the calculation result obtained by the calculation means 22 is displayed at the above-mentioned predetermined position of the display device 26 and the data is printed out, so that the inspector can confirm the result of the brake test. You can

In the above embodiment, the brake type determination means 24 compares the measured value (X) of the front wheel sum as the main brake wheels excluding the parking brake wheel with 1/4 (Y) of the front wheel sum prescribed value and the rear wheel sum. However, the drag force may be compared with the drag force determined by the vehicle type. This dragging force means the weight of the vehicle 10 and the components that make up the brake (pads, rotors, etc.) without operating the brake when the vehicle 10 is set on the measuring device.
A resistance acts on the roller 12 due to the mutual contact, and this is the force detected as the braking force. This dragging force has different values depending on the vehicle type, the type of disc or drum in the brake, the precision of parts, and the like, and is predetermined according to the vehicle type, and can be set to, for example, about 20 kg.

FIG. 5 shows an example of the case of determining the brake type based on this drag force. In the figure, the operation steps themselves are the same as those in FIG. Assuming that the drag force is 20 kg, which is the standard value, the measured value X of the sum of the front wheels is compared with 20 kg.

[Effects of the Invention] As described above, according to the present invention, the brake type determination means is provided to automatically determine whether the main brake is operating or the parking brake is operating. Therefore, the brake braking force test can be easily performed by simply depressing the main brake pedal or pulling the parking brake lever with a predetermined force, without relying on the inspector's intuition or experience. The measurement and inspection can be performed with high efficiency and high accuracy.

In addition, even when inspecting many types of vehicles with different standards for braking force, you can automatically inspect the brakes of any type of vehicle by simply selecting the vehicle type, which also puts a burden on the inspector. It has the effect of being significantly reduced.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an automatic braking force measuring device according to the present invention, FIG. 2 is a detailed circuit block diagram of the configuration of FIG. 1, and FIGS. 3 and 4 are flow charts for explaining the operation of the embodiment. 5 and 5 are flow charts for explaining the operation of another embodiment. 10 …… Vehicle 12 …… Roller 18 …… Load cell 20 …… Measurement means 22 …… Calculation means 24 …… Brake type determination means 26 …… Display device 28 …… Vehicle type selection switch

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshinori Takizawa 1-6-2 Moto-Akasaka, Minato-ku, Tokyo Safety Automobile Co., Ltd. (56) Reference JP-A-54-51101 (JP, A) JP 62-56837 (JP, A) Actual opening 58-86543 (JP, U) Actual opening 60-118747 (JP, U) Actual opening 60-118740 (JP, U)

Claims (3)

[Claims] 1. A four-wheel vehicle is run on rollers that rotate at a constant speed, and the braking force applied to all four wheels by the main brake is measured, and the braking force applied to one of the two wheels is measured by the auxiliary brake. Then, in the braking force automatic measuring device that displays the result, the measured value of the braking force of the other two wheels is compared with the first predetermined value, and if this measured value is larger than the first predetermined value, the main brake is in the operating state. When the measured value of the braking force of the other two wheels is smaller than the first predetermined value, the sum of the measured values of the braking force of the one two wheels is added to the braking force of the other two wheels. When the sum of the measured values of the braking forces of one of the two wheels is larger than a predetermined difference by more than the sum of the measured values of the braking forces of the other two wheels, the auxiliary brake is in the operating state. Equipped with a brake type determination means for secondarily determining that An automatic braking force measuring device characterized by automatically determining whether it is the operating state of the auxiliary brake. 2. The device according to claim 1, wherein the brake type determination means uses a drag force detected as a braking force based on resistance to the roller as the first predetermined value. Automatic braking force measuring device. 3. The device according to claim 1 or 2, wherein the brake type determination means is configured to determine whether the braking force of the other two wheels is smaller than a first predetermined value. The measured value of the braking force of the two wheels is compared with the second predetermined value, and this measured value is the second value.
An automatic braking force measuring device characterized by determining that the auxiliary brake is in an operating state when the braking force is larger than a predetermined value.