JPH05126682A - Vehicle lifting device - Google Patents

Abstract

PURPOSE:To float a vehicle under test on a chassis dynamometer and perform a correct travel simulation by integrally stacking a height adjusting actuator and an operating actuator, and connecting a reservoir tank to the operating actuator. CONSTITUTION:A height adjusting actuator 12 connects a communicating tube 15 connected inside to a water hydraulic or oil hydraulic source, and it lifts or lowers a support base on the actuator 12 from the lower position to the high position at a slow speed. An operating actuator 14 for lifting load is connected with a communicating tube 16 to a reservoir tank 18 via an electropneumatic converter 17. A compressor 19 is connected to the tank 18, and the compressed air at the fixed pressure is invariably filled in the tank 18. The actuator 14 quickly lifts the load when it receives the compressed air in the tank 18, and it quickly lowers it when the compressed air is released. The same state as the load movement during braking can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle levitation device used for levitation of a vehicle mounted on a chassis dynamometer to perform a low friction road traveling simulation.

[0002]

2. Description of the Related Art Generally, a chassis dynamometer is used as a device for conducting a test in a running state of a vehicle. In this, various running states such as high speed and low speed, and various states such as climbing and descending plate running can be simulated on the roller to perform a test. In recent years, chassis dynamometers have been used to test low friction road surface conditions on ice and snow, as well as vehicles equipped with ABS (anti-lock brake system) and vehicles equipped with trunk control. Has been requested.
Therefore, conventionally, instead of changing the friction coefficient between the tire of the vehicle under test and the roller of the chassis dynamometer, by adjusting the wheel load applied to the roller, it is possible to simulate a road surface with an arbitrary friction coefficient. FIG. 7 and FIG.
A chassis dynamometer such as that shown in FIG. As shown in FIG. 7, the front and rear wheels of an automobile 1 are placed on two rollers 2 and 3, respectively, and a flywheel 4 and a dynamometer 5 are connected to the rollers 2 to show the characteristics of the automobile 1 on a chassis. It is configured to measure.

Further, in order to adjust the wheel load applied to the roller by the above-mentioned chassis dynamometer, a vehicle levitation device as illustrated in FIG. 8 is installed. This vehicle levitation device is configured as a hydraulic jack. A hydraulic cylinder portion 7 is installed on a floor 6 of a chassis dynamometer, and a tip end portion of a piston rod 8 thereof is pushed against an axle portion 10 of a tire 9 in a vehicle under test. Configure to hit. Then, by operating this vehicle levitation device, the vehicle under test is lifted,
By weakening the contact pressure between the roller 2 and the tire 9 and weakening the frictional force acting between them to cause slippage, it is possible to test an antilock brake system or the like on a low friction road surface state.

Conventionally, as the vehicle levitation device, a screw type or pneumatic type jack has been used in addition to the hydraulic type.

[0005]

The conventional vehicle levitation device (hydraulic type, screw type, pneumatic type) as described above is the same as a general jack, and the vehicle under test is set at a constant height.
Since it was intended to levitate slowly, it was not possible to control the levitating amount of the vehicle in a short time.

For this reason, conventionally, a problem may occur when a brake performance test is performed on a four-wheel chassis dynamometer. This is because when the vehicle under test is first levitated to a certain height and the wheel weight is reduced to a level corresponding to a low friction road to perform a brake test, the front wheels are weighted and the rear wheels are weighted. This is a phenomenon called load movement due to brakes, which also occurs on the chassis dynamometer, but because the vehicle under test is restrained before and after it is placed on the chassis dynamometer, there is less load movement than in the actual running state. It did not occur and caused the inconvenience that accurate simulation could not be performed.

Therefore, in order to cause such a load movement when the brake is applied to be the same as when the vehicle is traveling on an actual road, a means for operating the levitation device at a high speed in conjunction with the brake to reproduce an actual load movement state is provided. Conceivable. However, the conventional vehicle levitation device has a problem that high-speed operation control capable of reproducing the load moving state cannot be performed, and the simulation in the load moving state during braking cannot be accurately performed.

In view of the above points, the present invention provides a vehicle levitation device capable of high-speed control operation, in which a vehicle under test is levitation-operated on a chassis dynamometer to accurately reproduce a load movement state and to perform traveling simulation and the like. It is intended to be newly provided.

[0009]

In a vehicle levitation device, a height adjusting actuator and an operating actuator are stacked and integrated, and a reservoir tank filled with compressed air is connected to the operating actuator via an electropneumatic converter. It is characterized in that it is configured.

[0010]

With the above structure, the height adjusting actuator lifts the actuator to the basic height position. Then, the actuating actuator is rapidly filled with compressed air prepared by filling the reservoir tank with a control operation of the electropneumatic converter to cause a rapid ascent operation, and is rapidly discharged with a control operation of the electropneumatic converter. Then, the descent operation is performed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle levitation device according to the present invention will be described below with reference to FIGS. 1 to 7, parts corresponding to those of the conventional example shown in FIGS. 8 and 9 are designated by the same reference numerals, and detailed description thereof will be omitted. FIG. 1 is a partial cross-sectional schematic configuration explanatory diagram illustrating a vehicle levitation device of this example, and 11 is an actuator section. The actuator portion 11 is formed by stacking the actuating actuators 14 on the height adjusting actuators 12 via the abutment 13 and integrally forming the actuating actuators 14, each of which is formed of a bellows formed of an elastic material.

The height adjusting actuator 12 is constructed by connecting a communication pipe 15 connected to the inside thereof to a water pressure or hydraulic pressure source (not shown). Then, the hydraulic pressure or the hydraulic pressure of the hydraulic pressure source is adjusted so that the abutment on the height adjusting actuator 12 can be moved up and down at a normal slow speed from a predetermined low position to a high position.

Since the actuating actuator 14 is for controlling the levitation load, it operates pneumatically. Therefore, the communication pipe 16 of the actuating actuator 14 is connected to the reservoir tank 18 via the electropneumatic converter 17. A compressor 19 is connected to the reservoir tank 18 so that it is always filled with compressed air having a constant pressure. The actuating actuator 14 of the present embodiment configured as described above is supplied with the compressed air in the reservoir tank 18 by the operation of the electropneumatic converter to rapidly levitate, and is rapidly descended by releasing air. It is a thing.

Next, a concrete example in which the vehicle levitation device of the present example configured as described above is mounted on the chassis dynamometer will be described with reference to FIGS. 2 to 6. In the schematic side view of FIG. 2, 1 is an automobile, 2 and 3 are rollers, 6 is a floor, 9 is a tire, 11 is an actuator portion, 17 is an electropneumatic converter, and 18 is a reservoir tank. In the apparatus of this example, one beam 20 is installed on the two actuator units 11 so as to bridge it, and is configured as one apparatus.

As shown in FIG. 6, the actuator section 11 comprises a height adjusting actuator 12 on which a support 13 is installed, on which an actuating actuator 14 is installed. Beam 20
As shown in FIGS. 4 and 5, is a long member, and a cylindrical axle support 21 is installed in the center of the upper surface.

As described above, the actuators 11 installed at both ends of the beam 20 are installed on the floor 6 of the chassis dynamometer as shown in FIGS. 2 and 3, and each tire 9 of the automobile 1 is installed. Place it in the inner position. Furthermore, the axle support 2 for each beam 20 arranged in this way
1 is brought into contact with the axle of each tire 9.

The actuating actuators 14 of the two actuators 11 installed at both ends of each beam 20 are connected to one reservoir tank 18 through each electropneumatic converter 17 by a communication pipe 16. Also, as shown in FIG.
Each of the two reservoir tanks 18 is connected by a conduit 22 to a compressor (not shown) so that compressed air is supplied from the compressor.

Next, the operation of the vehicle levitation device installed in the chassis dynamometer as described above will be described. First, in the case of traveling simulation on a low friction road, the height adjusting actuator 12 is operated to raise the abutment 13 to a predetermined height. Next, while being controlled by the electropneumatic converter 17, the actuating actuator 14 is filled with compressed air to raise the beam 20 to a required height position. At this time, the axle support 21 of the beam 20 presses the axle from below to lift the automobile 1 as a whole by a required amount, reduce the wheel load of the tire 9 on the rollers 2 and 3, and reduce the frictional force that acts during this. The test can be performed in the same condition as the low friction road.

Next, in the case of conducting a test involving load movement by a brake, the electropneumatic converter 17 on the front wheel side is controlled in conjunction with the brake operation, and the pressure inside the actuating actuator 14 on the front wheel side is reduced at high speed. Make sure that the front wheels are weighted. At the same time, the electropneumatic converter 17 on the rear wheel side is controlled in conjunction with the brake operation to rapidly fill the working actuator 14 on the rear wheel side with the compressed air in the reservoir tank 18 to reduce the load applied to the rear wheel. To reduce. By such high-speed control, load movement during braking is caused in the same manner as an operation on an actual road, and a test suitable for an actual situation is possible.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0021]

As described above in detail, according to the vehicle levitation device of the present invention, the height adjusting actuator and the working actuator are stacked and integrated, and the working actuator is filled with compressed air through the electropneumatic converter. Since it was configured by connecting the reservoir tank, the actuator for height adjustment lifts it to the basic height position. Then, the actuating actuator is rapidly filled with compressed air prepared by filling the reservoir tank with the control operation of the electropneumatic converter to cause a rapid ascent operation, and the air is rapidly released with the control operation of the electropneumatic converter. When the vehicle levitation device is mounted on a chassis dynamometer, etc., each wheel of the vehicle under test is rapidly raised or lowered to the required height in conjunction with the braking action. As a result, a state similar to the load movement during braking can be realized, and in addition to this, there is an effect that a rapid lifting operation is possible.

Further, since the volume of the actuating actuator can be made smaller than that which is constructed as an actuator of a single container as a whole, there is an effect that a high speed operation can be realized by controlling the air pressure.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional schematic configuration explanatory diagram showing an example of a vehicle levitation device of the present invention.

FIG. 2 is a schematic side view showing a specific embodiment in which the vehicle levitation device of the present invention is mounted on a chassis dynamometer device.

FIG. 3 is a schematic plan view of the specific example.

FIG. 4 is a side view of the vehicle levitation device portion of the above specific example.

FIG. 5 is a plan view of a vehicle levitation device portion of the specific example.

FIG. 6 is a partial cross-sectional front view of an actuator portion of the above specific example.

FIG. 7 is a schematic side view illustrating a conventional chassis dynamometer.

FIG. 8 is a partial cross-sectional view of a main part illustrating a vehicle levitation device mounted on the chassis dynamometer.

[Explanation of symbols]

 1 ... Automobile 2,3 ... Roller 6 ... Floor 9 ... Tire 10 ... Axle 11 ... Actuator part 12 ... Height adjustment actuator 13 ... Abutment 14 ... Actuator 15,16 ... Communication pipe 17 ... Electro-pneumatic converter 18 ... Reservoir tank 20 ... Beam 21 ... Axle support

Claims (1)

[Claims] 1. A vehicle characterized in that a height adjusting actuator and an operating actuator are stacked and integrated, and a reservoir tank filled with compressed air is connected to the operating actuator via an electropneumatic converter. Levitation device.