JPS62284237A - Chassis dynamo for brake test - Google Patents

Abstract

PURPOSE:To take a brake squeak test on a chassis dynamo by simulating an actual run state by using the hydraulic pressure and speed reduction pattern of a brake in an actual run test. CONSTITUTION:The brake squeak test of a vehicle 10 to be inspected is taken on an actual run road and the master cylinder hydraulic pressure and speed reduction pattern at this time are measured and set in a hydraulic pressure setter 44 and a speed reduction pattern generator 72. Then, the detection output of the hydraulic pressure sensor 54 which detects the hydraulic pressure in a master cylinder 26 is inputted to an actuator during the test and a cylinder 50 is brought under feedback control so that a value equal to the set value of the hydraulic pressure setter 44 is obtained. Further, the detection signal of a rotating speed sensor 74 and the output of the speed reduction pattern generator 72 are collated by a collator 78 with each other and an ASR circuit 80 adjusts electric power supplied to a dynamometer 16 from a three-phase AC power source 84 so that the detection signal coincides with the speed reduction pattern.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a chassis dynamometer for testing brakes, and particularly to improvements to a chassis dynamometer for testing brake squeal.

[Prior Art] As vehicle performance improves, vehicle brakes are also required to have higher performance, and in particular, it is required to effectively suppress brake squeal during vehicle braking.

Although this type of brake squeal does not have any effect on the braking characteristics of the vehicle, it causes psychological anxiety and discomfort to the driver and those around them, so it is especially important to avoid brake squeals installed in high-performance cars. It is required to suppress this as much as possible, and for this reason, various brake squeal tests have been conducted in the past.

As one of such brake squeal tests, actual driving tests have been widely conducted in the past, in which a test vehicle is actually driven on a test course and brake tests are repeatedly performed.

Actual driving tests can directly verify whether brake squeal occurs under actual driving conditions, so extremely useful data can be obtained.

On the other hand, brake squeal tests are generally conducted repeatedly using vehicle running speed and brake pedal depression/depression as parameters. For this reason, it took several hours from the start to the end of the test.
It takes several tens of hours, tends to cause test driver fatigue, is easily affected by weather, and has the problems of requiring scheduling with other actual driving tests on the test course. Was.

For this reason, there is a known device that uses a chassis dynamo to perform brake squeal tests indoors.
A brake squeal test is conducted by placing both the left and right wheels of the test vehicle in contact with a pair of rollers on a chassis dynamo, simulating actual driving conditions on these rollers.

Figure 3 shows an example of a conventional chassis dynamometer for brake testing. A mechanical flywheel 14 is connected which simulates the inertia of the roller 1.
A motion meter 16 is connected to 2, and is used to evaluate the braking force characteristics of the vehicle during acceleration and deceleration of the vehicle, and particularly to analyze the so-called brake squeal phenomenon that occurs when normal deceleration tJI movement is performed from the running state.

[Problems to be Solved by the Invention] However, such conventional devices have various problems described below, and effective countermeasures have been desired.

In addition, such a conventional device simulates an inertia m equivalent to the vehicle weight using a mechanical flywheel 14, and sets the amount of inertia by increasing or decreasing the number of flywheels 14 connected to the rollers 12. ing.

Therefore, since the inertia amount can only be set in stages, it is inevitable that a setting error will occur between the set inertia amount and the actual vehicle weight. There was a problem in that the braking condition could not be accurately reproduced on the chassis dynamometer.

As a result, with such conventional devices, even if the vehicle generates the same braking force as when it is actually driving, the deceleration is different from when it is actually driving on the road, and the so-called brake squeal phenomenon is suppressed by chassis dynamics. There was a problem that it was not possible to accurately analyze the above.

Even with such a conventional device, it is possible to finely simulate the amount of inertia by increasing the number of mechanical flywheels 14 prepared, but in this way, the installation space of the mechanical flywheels 14 will be reduced. There is a problem in that the size of the device becomes extremely large, and the entire device becomes large and effective.

2nd;:1 In such a conventional device, the chassis dynamo t-
A driver 100 actually rides in a test vehicle running in a simulated manner during a long brake squeal test.

For this reason, as in the case of actual driving tests, driver 1
There was a problem in that it easily caused fatigue.

Furthermore, in conventional IC1 systems like this, the brake pedal pressure control relies on the senses of the driver 100, so it depends on the driver's skill level. There was a problem that the brake squeal test could not be performed properly and the noise level was not 8 degrees.

[Purpose of the Invention] The present invention has been made in view of such conventional problems, and its purpose is to perform a vehicle brake test, especially a brake squeal test, without requiring a driver, and on the actual road. Our goal is to provide a chassis dynamo for brake testing that can accurately simulate driving with high accuracy.

[Means for Solving the Problems] Point of Interest When conducting a brake test on a vehicle, the inventors of the present invention consider three factors: the oil pressure in the master cylinder of the brake, the braking torque of the vehicle, and the deceleration pattern of the vehicle. Focusing on the relationship between
After examining these relationships, we found that once the braking torque and deceleration pattern are determined, the remaining oil pressure is automatically determined, and when the oil pressure and deceleration pattern are determined, the remaining braking torque is automatically determined. It was.

Δ! The invention is based on 1 like this, and the actual driving condition L)
(The hydraulic pressure and FIUI pattern of the brakes used for knee djing are accurately simulated to accurately simulate the actual driving conditions, and the present invention corresponds to both the left and right wheels of the test vehicle.)
A brake control device that controls the brakes of a test vehicle in a chassis dynamo that performs a brake test on a test vehicle, including a pair of provided rollers and a dynamometer connected to each of these rollers. 'i and before) 1L! a dynamometer control device that controls the output of the dynamometer;
including.

(The brake control device includes: a control hydraulic circuit connected to a master cylinder hydraulic circuit of the brake; a hydraulic pressure detection sensor for the control hydraulic circuit; and a hydraulic pressure setting device for setting a desired hydraulic pressure. The hydraulic pressure of the master cylinder is feedback-controlled to a set value based on the output of the hydraulic pressure detection sensor. a deceleration pattern generator that generates a deceleration pattern of the inspection vehicle;
It is characterized by noise back control.

[Takeda] The present invention has the above configuration, and its operation will be explained next.

Start the experiment on the chassis dynamo.

In this way, braking torque corresponding to the brake oil pressure and deceleration pattern is automatically applied to the left 8 wheels of the vehicle, accurately simulating the actual vehicle driving condition, and
Brake tests can be performed.

In particular, the device of the present invention uses a brake controller to control brake master cylinder oil pressure without the need for a driver. Therefore, if the output of the oil pressure setting device and the deceleration pattern generator/1 device are switched and controlled so that the brake squeal test is repeatedly performed using the brake master cylinder oil pressure and deceleration pattern as parameters, it is possible to maintain braking for a long time. 21- It becomes possible to perform the squeal test automatically and with high accuracy without requiring a screwdriver.

[Example] Next, a preferred example of the present invention will be described based on the drawings. Note that the members corresponding to the conventional device have the same t, lr;
, and its explanation will be omitted.

FIG. 1 shows a preferred example of the chassis dynamometer for brake testing according to the present invention, in which both the left and right wheels 20.20 of the vehicle to be tested 10 are brought into contact with a pair of rollers 12.12, and the chassis dynamometer is The actual driving of the test vehicle 10 is simulated above.

Brakes corresponding to the type of vehicle are provided on both the left and right wheels 20 and 20 in front of the brake j1. For example, if a disc brake 22 is provided as such a brake, when the brake pedal 24 is stepped on, the master cylinder 26
The hydraulic pressure increases and is transmitted to the caliper 30 via the play 1 via 28, thereby operating the disc brake 22.

In order to perform such a brake 22 test, especially a rake squeal test, the present invention provides a brake control device 40 that controls the brakes of the test vehicle 10, and a dynamometer control device that controls the output of the power i, +16. 70 is provided.

ZL/--Main control device The brake control bag @40 is a control hydraulic circuit 4 directly connected to the hydraulic circuit of the master cylinder 26 of the brake.
2 and oil pressure L9 constant: S44 for setting a desired oil pressure, the oil L1 of the master cylinder 26 is controlled to a desired setting value.

In the embodiment, the control hydraulic circuit 42 has a pi/46
The first cylinder 48 is directly connected to the hydraulic circuit of the master cylinder 26 via the hydraulic circuit of the master cylinder 26, and the second cylinder 50 is coaxial with the first cylinder. The hydraulic pressure of the master cylinder 26 is controlled to a desired value by driving the second cylinder 50.

A hydraulic pressure sensor 54 is provided within the first cylinder 48 to detect the hydraulic pressure within the master cylinder 26, and its detection output is input to the actuator 52 via the amplifier 5b.

The actuator 52 includes a verifier 56, an amplifier 58, a hydraulic tank 60, a pump 62, and a hydraulic controller 64, and includes a detection output of the sensor 54 and oil): 1-setting device 440.
The second cylinder 50 is feedback-controlled so that the set value matches the set value.

In this way, according to the -brake control bag ff1-0, the brake control bag @40 and the master cylinder 26 can be operated without the need for a driver, especially according to the present invention.
and connected via pipe 46 to V, S, and brake control bag @4
Since the 0 and brake side hydraulic circuits are completely separated, the mask cylinder hydraulic pressure can be controlled from the outside without loading the brake control device 40 into the test vehicle, making it easy to prepare for the brake noise σ test. becomes possible.

Furthermore, since the brake control VT@40 directly controls the oil LF of the mask cylinder 26 instead of the brake pedal 24, it is possible to control the braking force of the brake in a responsive manner and with extremely high reproducibility. becomes possible.

Furthermore, in the present invention, the dynamometer control device 70 includes a speed sensor V that detects the running speed of the test vehicle 10, and generates a deceleration pattern of the test vehicle 10 during a brake test. and a deceleration pattern generator 72 configured to feedback control the rotational speed of the dynamometer 16 according to the deceleration pattern IS.

In the embodiment, the speed sensor is configured to convert the detection signal of the rotation speed sensor 74 of the dynamometer 16 into a voltage signal using a signal converter 76 and output the voltage signal.

Then, the detection signal of the rotation speed sensor 74 and the output signal of the deceleration pattern generator 72 are collated by a collation device 78, and the AS
R (Automatic 5peed Regulat
er) is input to the circuit 80.

The ASR circuit 80 controls the SCR circuit 82 so that the rotational speed of the dynamometer 16 matches the speed signal output from the deceleration pattern generator 72, and supplies the dynamometer 16 from the three-phase AC power source 34. We are making adjustments to the electric horns that will be used.

(2) The present embodiment has the above configuration, and its operation will be explained next.

When the left and right wheels 20 of the test vehicle 10 are brought into contact with the rollers 12 and simulated running is performed on the rollers 12, each rotating roller 12 functions as an endless flat road instead of an actual road surface.

At this time, by applying a rotational load equal to the load applied to both the left and right wheels 20 of the test vehicle 10 on the actual running route through the rollers 12 using the dynamometer 16, a simulated run equivalent to the actual running is performed on the rollers 12. The i′J state can be reproduced.

The present inventors investigated the hydraulic pressure of the brake master cylinder, the deceleration pattern of the test vehicle 10, and the braking torque when the test vehicle 10 was actually run on a test course and a brake test was conducted. After focusing on these factors and examining their relationships, it was confirmed that once the master cylinder oil pressure and vehicle deceleration pattern are determined, the value of the braking torque is automatically determined.

Therefore, according to the present invention, if a brake squeal test is performed on the test vehicle 10 on an actual running road and the master cylinder oil pressure and deceleration pattern at that time are measured, the oil pressure can be set in the oil pressure setting device 44. By setting a deceleration pattern in the deceleration pattern generator 72 and controlling the oil pressure of the master cylinder 26 and the rotation speed of the power L+ 16, the left and right wheels 20 of the test vehicle 10 are subjected to the same braking as on the actual traveling road. Torque is added, making it possible to accurately analyze the so-called brake squeal phenomenon.

FIG. 2 shows measurement data obtained when a brake squeal test was repeatedly conducted on an actual driving road using the oil pressure of the master cylinder 26 and the deceleration pattern as parameters.

According to the present invention, the deceleration pattern generator 72 is set to sequentially output the previous 1-deceleration pattern according to the time schedule shown in FIG. 2, and the oil pressure setting device 44 is set to output the brake oil pressure as shown in FIG. By setting the brakes to be output sequentially according to a time schedule, it is possible to repeatedly conduct a brake squeal test on a chassis dynamo using oil pressure and deceleration pattern as parameters, accurately simulating actual driving.

In addition, in order to control the braking force of the brake, the device of the present invention uses measurement data from a brake test conducted using a chassis dynamo and measurement data from a so-called brake unit test (a test performed without the brake mounted on the vehicle). It is also possible to analyze the brake squeal phenomenon by comparing it with the above.

a3. In the above-mentioned embodiments, a case where a brake squeal test is performed as a brake test has been described as an example, but the present invention is not limited to this, and can also be used for other brake tests.

[Effects of the Invention] As described above, according to the present invention, it is possible to perform a brake test on a test vehicle, particularly a brake squeal test, without requiring a driver.

1) According to the present invention, if the mask cylinder oil pressure and deceleration pattern of the brake are known when the test vehicle is actually driven and a brake test is performed, this actual running can be accurately recorded on the chassis dynamometer. It becomes possible to perform a brake test by simulating it.

Further, according to the present invention, since a mechanical flywheel is not required, the entire device can be made small and inexpensive.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a preferred embodiment of the brake test chassis dynamo according to the present invention, FIG. It is a diagram. 10...Test vehicle 12...Roller 16...Dynamometer 20...Wheel 22...Brake 26...Master cylinder/10...Brake control device 42...Control hydraulic circuit 44... Oil pressure setting value 70... Power control device 72... Deceleration pattern generator 74... Rotation speed sensor

Claims (2)

[Claims] (1) On a chassis dynamo that performs a brake test on a test vehicle, which includes a pair of rollers provided corresponding to the left and right wheels of the test vehicle and a dynamometer connected to each of these rollers, a brake control device that controls the brakes of the brake, and a dynamometer control device that controls the output of the dynamometer, the brake control device comprising: a control hydraulic circuit connected to a brake master cylinder hydraulic circuit; an oil pressure detection sensor for a control oil pressure circuit; and an oil pressure setting device for setting a desired oil pressure; the dynamometer control device feedback-controls the oil pressure of the master cylinder to a set value based on the output of the oil pressure detection sensor; , a speed sensor that detects the running speed of the test vehicle, and a deceleration pattern generator that generates a deceleration pattern of the test vehicle during a brake test, and feedback controls the rotational speed of the dynamometer according to the deceleration pattern. Chassis dynamo for brake testing featuring: (2) A chassis dynamo for brake testing in the apparatus according to claim (1), wherein the speed sensor is formed using a rotation speed sensor that detects the rotation speed of a dynamometer.