JPS62197741A - Controller for chassis dynamometer - Google Patents

Abstract

PURPOSE:To enable accurate noise and vibration tests, by a method wherein the revolutions of front and rear shafts are detected with a speedometer to give an input of an increment/decrement counter to control a dynamometer with the difference between the counts and a set value as rotational difference command. CONSTITUTION:Speedometers 15 and 16 detected revolutions of front and rear wheels of a 4WD car 10, namely, those of rotors of dynamometers 13 and 14 and control sections 17 and 18 control meters 13 and 14. F/V (frequency/voltage) converters 19 and 20 performs a F/V conversion of detection outputs of the speedometers 15 and 16. An increment/decrement counter 21 measures a difference between revolutions of the speedometers 15 and 16. An operational amplifier 23 takes a deviation of outputs of the converters 19 and 20. A D/A converter 24 converts a difference into analog from digital between an output of the counter 21 and a set value of a phase difference setter 22. An operational amplifier 25 computes a deviation between the outputs of the converter 24 and the amplifier 23 and supplies the output thereof to a controller 17 while a polarity inversion amplifier 26 supplies an output of the amplifier 25 to a control section 18 in inverted polarity to perform a control so that the phase difference between both the shafts reaches a set value.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a control device for a chassis dynamometer that performs dynamic tests by mounting the drive wheels of a vehicle on rollers and driving the vehicle instead of on a road. .

B6 Summary of the Invention The present invention provides a chassis dynamometer in which a dynamometer is connected to a front axle roller and a rear axle roller on which the driving wheels of an automobile are mounted. By detecting i+tt and using it as an input to the up/down counter 2, and controlling the dynamometer by using the difference between this count value and the set value as a rotation difference command, the phase of the front axle roller and rear axle roller is set. This value is maintained to perform noise and vibration tests on 4WD vehicles, and rough road driving tests are performed by providing protrusions on the rollers.

C4 Conventional technology Chassis dynamometer has a configuration in which the rotating shaft of a roller 1 is connected to the rotating shaft of a dynamometer 4 via a gear (speed increaser) 2° flywheel 3, as shown in FIG. 5, for example. Dynamic test 1 is carried out by placing the driving wheels of a car on the roller 1 and running it instead of on a road.The roller shaft is subjected to the same load (running resistance) as when running on an actual road, and the actual running is carried out. The state should be as close as possible to .

D3 Problems to be solved by the invention Chassis dynamometers can perform various tests such as membrane performance tests, exhaust gas tests, and sound tests. In the case of 4TI rear-wheel drive JiL (4WD vehicle), there are 11 unique features such as matching the phase of the front and rear axle rollers. ! 3111 is required.

Means for Solving Problem E1 The present invention uses a chassis dynamometer that connects dynamometers to the front and rear axle rollers mounted on the drive wheels of the automatic kite being tested. The rotational speed of the shaft and rear shaft is detected by a Keparus Bickr-yy type speedometer and used as input to the up-down counter, and the difference between this counted value and the set value is used as a rotational difference command to control the dynamometer. That is.

21 action The rotation speed of the front and rear axles detected by the pulse pickup type speedometer is counted by the up/down counter, and the difference between this counted value (phase difference) and the value set by the phase difference setting device becomes the rotation difference command. , is D/A converted and supplied to the control unit of the dynamometer, where it is controlled so that the phase difference between both axes becomes a set value.

As a result, noise and vibration tests for 4WD vehicles and rough road driving tests are conducted.

G. Embodiment FIG. 1 shows an embodiment of the present invention, in which 10 is the 4WD vehicle to be tested, 11 and 12 are the front wheels, which are the drive wheels of this automobile, and the rollers on which the rear wheels are placed, 13 and 14
is a dynamometer connected to both rollers 11 and 12,
Reference numerals 15 and 16 refer to pulse pickup type speedometers for detecting the rotational speed of the rotors of the front wheels, VK wheels, or dynamometers 13 and 14 of the automobile 10; 17 and 18 control units for the dynamometers 13 and 14; 20 is an F/V converter that converts the detection outputs of the speedometers 15 and 16 into F/V (frequency-voltage), and 21 receives the outputs l of the speed hands 15 and 16 and measures the difference in rotation speed. Up/down counter, n is a phase difference setter that sets the phase difference θl,
23 is an operational amplifier that receives the outputs of the F/V converters 19 and 20 and calculates the deviation thereof; 24 is the difference between the output of the counter 21 and the setting value of the setting device n;
A D/A converter 25 for converting (analog) converts the output of the D/A converter 24 and the amplifier 23 by -1 PI, and calculates the output value of the D/A converter 25.
26 is a polarity inverting amplifier that inverts the polarity of the output of the amplifier 25 and supplies it to the control section 18.

With such a configuration, the rollers 11° and 12 on the front and rear axles are
The angle θ is set so that the phase difference becomes zero, and the setting device 22 is used to set the angle θ to an arbitrary value. When a test is started in this state, the output of the up/down counter 21 is zero and the set value is θ, so the output of the D/A converter command becomes a command to cause a rotation difference. As a result, a rotation difference is generated by the control of the rotation difference control loop.

Since the integral of the rotation difference is the phase difference θ, the output of the D/A converter gradually decreases, and the set value and up/down counter 2
The outputs of 1 will be equal. That is, the rotation difference command becomes zero.

The hawk in this state is shown in Figures 2 and 3.

Controlling the phase difference in this way means controlling the tooth contact of the front and rear differentials, allowing tests for noise and vibration analysis. This is because the tooth contact of the center differential gear device is constantly maintained at the same position by controlling the phase l, and if the phase is shifted, the planetary gears of the center differential gear device rotate and the tooth contact shifts.

In addition, as shown in FIG. 4, the rollers 11 and 12 have projections 1.
If 1A and 12A9 are provided and the phase is controlled to a rotation angle θ that has a circumference equal to the interval t before and after automatic J[10, military 1
After the front wheel of 0 jumped up on the protrusion 11A of the roller 11,
The rear wheel jumps up on the protrusion 12A of the roller 12 after a delay of the interval, and a driving test on a rough road (uneven road) becomes possible.

Effect of H1 invention As described above, according to the present invention 1, there is provided a front wheel of an automobile.

Detect the rotation a'v of two dynamometers connected to the rollers mounted on the rear wheel, input these to the up/down counter to detect the phase difference between both rollers, and calculate the difference between this value and the phase difference setting value. Since dynamometer control is used as the difference command, it is possible to control the tooth contact of the front and rear differentials, making it possible to perform accurate noise and vibration tests, and by providing protrusions on the rollers, it is possible to perform running tests on rough roads. is also possible.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a control device for a chassis dynamometer according to the present invention, and FIGS. 2 and 3 are characteristic diagrams of the same embodiment. Figure 4 is an explanatory diagram of a rough road driving test, and Figure Wx5 is a configuration diagram of a general chassis dynamometer. 10...Automobile, 11 and 12...Roller, 11 people and 12A...Protrusion, 13 and 14...Dynamometer, 15 and 16...Speedometer, 17 and 18...
Control unit, 19 and 20... F/V converter, 21...
Up/down counter, 22... Phase difference setter, 24
...D/A converter, 25...Operation amplifier, 26...
・Polarity inversion amplifier. Figure 1 1o・・・・・・Ji1riki11 19.20
・・・・・・F//Jatoro ■Metsu Figure 2 Figure 4 Figure 3 Figure 5

Claims (1)

[Claims] (1) In a chassis dynamometer, which has a dynamometer connected to the front and rear axle rollers on which the driving wheels of the vehicle to be tested are mounted, the rotational speed of the front and rear axles is measured using a pulse pickup type speedometer. A control device for a chassis dynamometer, characterized in that the detected value is input to an up/down counter, and the difference between this counted value and a set value is used as a rotation difference command to control the dynamometer.