JPS5920833A - Testing apparatus for power steering device - Google Patents

Abstract

PURPOSE:To reproduce the state close to an actual vehicle and to test self-excited vibration caused by especially negatively inputted vibrations, by providing a pair of a spring type load absorbing device and a power steering device, and also providing two servo hydraulic actuators as positive and negative input vibrating devices. CONSTITUTION:When a switch is thrown to the positive input side, a servo hydraylic actuator 27 is actuated, a vibration input corresponding to a control signal is imparted to an input shaft 22, and a power steering device 20 is actuated. The power transmitted to a load absorbing device 11 through a rotary arm 15 is absorbed by a torsion bar 13, and self-excited vibration is reproduced. When the switch is thrown to the negative input side, a servo actuator 36 is actuated, and a reverse input is imparted to the steering device 20. Under this state, the actuator 27 is actuated through a torsion bar 23. Since the torsion bar 23 performs the absorbing action of the vibration imparted by a road surface, the self-excited vibration can be reproduced by the switching action under the state close to an actual vehicle.

Description

[Detailed Description of the Invention] Technical Field> The present invention relates to a testing device for a steering system including a power steering device, and in particular to a test device for testing a steering system including a power steering device, in particular vibration input frequency from the steering wheel side.
The present invention also relates to a test device suitable for examining self-excited vibration of a steering system in response to vibration input (negative input) from the road surface.

<Prior art> In general, in a power steering system, there is a delay in the response of the servo system compared to a manual steering system, so self-excited vibration is likely to occur when vibration human power is applied, and so-called goo noise is generated due to the self-excited vibration. Was. In order to eliminate such goo noise, it is necessary to prevent self-excited vibrations from occurring during normal steering operations. For this reason, test devices for investigating the occurrence of such self-excited vibrations have existed in the past.

Conventionally, in this type of test device, a vibration input is applied to the steering input shaft of a power steering device to check whether self-excited vibration occurs, the vibration generation situation with respect to the vibration input frequency, etc.

In contrast to such vibrations applied from the input shaft side, in an actual vehicle state, there are vibrations applied from the road surface, and this also causes self-excited vibrations. However, conventional test equipment cannot test vibrations with negative input, which corresponds to vibrations from the road surface.

<Purpose of the Invention> Therefore, an object of the present invention is to enable self-excited vibration testing of a power steering system by reproducing conditions close to those of an actual vehicle. The purpose of the present invention is to provide a test device that can perform the following tests.

<Example> Embodiments of the present invention will be described below based on the drawings.

1 and 2, reference numeral 10 indicates a base forming the main body of the test device, reference numerals 11.11 and 12.12 load absorbing devices erected on a holding table 12.12 and each load absorbing device are placed and fixed on the base 10. 11. 11 is a load torsion bar 13 whose lower end is fixed to a holding base 12 as shown in FIG. cylindrical member], 4; and a rotating arm 15 protruding radially from the outer peripheral surface of the cylindrical member 14.
It is designed to apply a splashing load due to the torsion of the

A power steering device to be tested is located between the pair of load absorbing devices 11 and 11, for example, an RkP type power steering device 20I? is attached by a holding base i. This steering device 2
Tie rods 21.21 are swingably connected to both ends of the rack shaft of 0 through ball joints (not shown), and the tip of each tie rod 21.21 is connected to a rotating arm 15.1.
5 via a ball joint 16.

One end of an input dosion bar 23 is connected to the input shaft 22 of the power steering device 20 , and the input dosion bar 23 is supported by a steering column 24 and held by a holding base 25 . One end of the input chamber 23 is connected to an output shaft 28 of a rotary servo hydraulic actuator 27, which is installed on a holding table 26 and serves as a positive input vibration device. This servo hydraulic actuator 27 has a servo valve 29.
A potentiometer 30 for detecting the rotation angle of the output shaft 28 is also provided. The load absorbing device 1
A second rotating arm 35 is protruded from one side of 1 (right side in FIG. 1), and a servo hydraulic actuator 36 as a negative input vibration device is connected to the rotating arm 35. It is installed on a holding table 37. 38 is a servo valve of the servo hydraulic actuator 36, and 39 is a potentiometer that detects the rotation angle of the cylindrical member 14 of the load absorbing device 16.

Note that 40 is a hydraulic power source, which supplies hydraulic pressure to the power steering device 20 and servo hydraulic actuators 27 and 36.

Next, the control system of each servo hydraulic actuator 27, 36 will be explained with reference to the block diagram shown in FIG. The servo valves 29 and 38 provided in each servo hydraulic actuator 27 and 36 are connected to the servo amplifier 4 via a changeover switch 41.
It is connected to the output side of 3. An arithmetic unit 44 is connected to the input side of the servo amplifier 43, a sine wave generating circuit 45 and a bias setting circuit 46 are connected as addition inputs of the arithmetic unit 44, and the potentiometer 30.
Each output of 39 is connected via a changeover switch 42. The respective changeover switches 4 and 42 are interlocked with each other, and the output of the potentiometer 30 or 39 on the servo valve side that is effectively connected to the servo amplifier 43 is fed back to the calculator 44, and the output is equal to the vibration amplitude of the bias set level. controlled so that The frequency of the vibration input can be adjusted by changing the time constant of the sine wave generating circuit 45 using known means, and is adjusted appropriately within the range of 10H2O from z. Note that 49 indicates the bias value. 47 is a peak value hold circuit that holds the detected amplitude level from the potentiometers 30 and 38 to a peak value, and 48 is an amplitude display that displays the value held at the peak value.

The operation of the above configuration will be explained. Changeover switch 41.4
2, the servo hydraulic actuator 30 for positive input excitation or the servo hydraulic actuator 36 for negative input excitation
can be enabled, and vibration input can be applied from the input shaft side of the power steering device 20 or from the output side according to control signals given from the sine wave generation circuit 45, the arithmetic unit 44, and the servo amplifier 43. Can be done. Changeover switch 41.42
If the positive input (lTlaK) is switched, the servo hydraulic actuator 30 becomes effective and gives rotational vibration to the input shaft 22. When rotational vibration is given to the input shaft 22, the servo valve 2 oas power of the power steering device 20 When the cylinder 20b operates, the rack shaft, tie rod 21, and rotating arm 15
Power is transmitted to and absorbed by the load absorbing device 11 via the load absorbing device 11. Since the torsion bar 13 is used for load absorption, the damping effect on the load absorption side is small, making it easier to oscillate, so self-excited vibration can be easily reproduced on the test stand.

Changeover switch 41.42f Negative human power @lb [If you switch,
The servo hydraulic actuator 36 becomes effective and applies a vibration input to the load torsion bar 13 side, and a reverse input is applied to the power steering device 20, so that a single force is transmitted to the input shaft 22 side. This input shaft 22vc is connected to the inactive servo hydraulic actuator 30 via the input shaft 23, so this input side torsion bar 23 becomes a load torsion bar at the time of negative input, and the input shaft 22vc becomes a load torsion bar during negative input. The action of absorbing the power transmitted to the This results in behavior that corresponds to the response characteristics of the servo system of the power steering device 20 with respect to vibrations applied from the road surface. In this way, in the case of a negative input, the torsion bar 23 connected to the input shaft 22 acts as a load torsion bar to absorb the load, and the damping effect is small, making it easier to oscillate. Vibrations can be reproduced on the test bench.

Effects> According to the present invention, a spring load is applied by a torsion bar as a load absorbing device, an excitation device for negative input is also provided on this load side, and a vibration device is provided between the input shaft and the vibration device for positive input. Since both are connected with a torsion bar, self-excited vibration in response to negative input, which was previously impossible, can be reproduced on the test stand in a state close to that of the actual vehicle, and by switching a switch, it is possible to reproduce the self-excited vibration in response to negative input Since self-excited vibration can also be reproduced on the same test bench,
It has the advantage of being useful as a bench test for improving the performance of power steering devices.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the entire test apparatus showing an embodiment of the present invention;
Figure 2 is its left side view, Figure 3 is ■-■ in Figure 1.
A sectional view taken along the line, and FIG. 4 is a control system block diagram of a servo hydraulic actuator. 011 Load absorbing device, 1
3... Load torsion bar, 14... Cylindrical member, 1
5... Rotating arm, 2o... Power steering device, 21.
... Tie rod, 22 ... Input shaft, 23 ... Input John bar, 2 people 366 ... Servo hydraulic actuator, 29.38 ... Sir 4j valve, 30.39 ... Potentiometer, 41.42 ... Selector switch, 43.
... Servo amplifier 144... Arithmetic unit, 45... Sine wave generation circuit. Patent applicant Toyota Machinery Co., Ltd. 2 Figure 2 Figure 3

Claims (1)

[Claims] (1) A pair of spring-type load absorbing devices comprising a base forming the main body of the test device, and a rotating member that is erected on the base at a distance from each other and rotatably supported via a load torsion bar. and a pair of rotating arms that protrude in the radial direction from the rotating members of the load absorbing device, and each rotating arm is connected to the tip of the rotating arm via a link such as a tie rod and fixed to the steering device holding base on the base. an input shaft connected to an input shaft of the power steering device; a first servo hydraulic actuator connected to one end of the input dosion bar and serving as a positive input vibration device; , a second servo hydraulic actuator connected to the tip of the rotating arm and serving as a negative input vibration device, and a periodically changing vibration selectively connected to a servo valve of the first or second servo hydraulic actuator. A test device for a power steering device, comprising an excitation control signal generation circuit that provides a control signal.