JPH0260247B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a test device for fatigue testing road surfaces or objects buried therein, and in particular to testing equipment for fatigue testing road surfaces or objects buried therein. This relates to a load device.

(b) Prior Art When a car runs on a road surface, the road surface is subjected to repeated loads from the driving of the car. The same applies to buried objects such as manholes buried in the road surface. Therefore, it is necessary to fatigue test the road surface and its buried objects. FIG. 3 shows a conventional test device. This device has a tire 1 and a hydraulic actuator 2, and the hydraulic actuator 2 is fixed to a frame 3. A tire 1, ie a wheel of a motor vehicle, is rotatably supported around an axle 4. And piston 5 of actuator 2
A pin joint 6 is provided at the piston 5 , and the piston 5 is connected to the axle 4 via the pin joint 6 . Furthermore, the specimen is placed in the soil or gravel 8 of the soil tank 7.
For example, a manhole 9 or a buried pipe 10 is buried, and the tire 1 is placed in the specimens 9, 10. Therefore, when hydraulic pressure is supplied to the hydraulic actuator 2, the piston 5 and the pin joint 6
, the axle is pushed down and a vertical load is applied to the tire 1. Next, the axle 4 is pulled up by the hydraulic actuator 2, the piston 5, and the pin joint 6, and the vertical load on the tire 1 is released. This is repeated alternately, and repeated loads are applied to the specimens 9 and 10 in the vertical direction. Therefore, the fatigue life of the specimens 9 and 10 against repeated loads can be tested.

However, this device can only apply a repeated load in the vertical direction to the specimens 9 and 10, and cannot apply a repeated load to the actual driving of an automobile. It is not possible to obtain accurate data on repeated traveling loads only by measuring repeated loads in the vertical direction. Therefore, there is a need for the development of a device that can apply repeated loads from driving a vehicle to a specimen.

(c) Purpose Therefore, the present invention was made for the purpose of applying repeated driving loads of an automobile to a specimen.

(D) Configuration This invention provides a method for arranging the wheels of an automobile at laterally spaced intervals from the vertical central axis of the device, supporting the wheels rotatably around the axle, and rotating the axle around the vertical central axis. Rotatably guide. A load mechanism that applies a vertical load to the wheel is located substantially on the vertical central axis and is connected to the axle. Further, a rotational drive mechanism such as a hydraulic motor is located substantially on the vertical central axis and is connected to the axle. and,
This rotary drive mechanism is characterized in that the axle is rotated around a vertical central axis, and the wheels are made to travel on the specimen.

(E) Examples Examples of the present invention will be described below. 1 and 2 show an embodiment of the invention. As in FIG. 3, a specimen, for example a manhole 11, is buried in an earthen tank 12. The device has a pair of left and right tires 13, ie, automobile wheels, which are spaced laterally from a vertical central axis 14 and rotatably supported about an axle 15. In this embodiment, three specimens 11 are arranged at angular intervals around a vertical central axis 14, as shown in FIG.
The spacing is selected such that the tire 13 is positioned on the specimen 11.

Further, this device has a hydraulic actuator 16, a rotating shaft 17, and a hydraulic motor 18, and the rotating shaft 1
7 is arranged concentrically with the vertical central axis 14, is fitted into a bush 20 of the bracket 19, and is rotatably guided. Bracket 19 is fixed to frame 21. Furthermore, the rotating shaft 17 and the axle 15
A pin joint 22 is provided in between, and the rotating shaft 17
is connected to the axle 15 via a pin joint 22. The hydraulic actuator 16 is located on the vertical central axis 14 and is fixed to the frame 21. The piston 23 is a thrust bearing 24
It is connected to the rotating shaft 17 via. Further, a detent pin 25 is fixed to the piston 23, and the detent pin 25 is engaged with the bracket 19. The hydraulic motor 18 is located on the vertical central axis 14 and is housed in the soil tank 12, and its reaction torque frame 26
Fixed. Then, the rotating shaft 1 is connected via the universal joint 27 and the spline 28.
It is connected to 7. The soil tank 12 is powered by a hydraulic motor 18
It has a piping trench 29.

In the apparatus configured as described above, when hydraulic pressure is supplied to the hydraulic actuator 16, the rotating shaft 17 is pushed down by the piston 23 and the thrust bearing 24. The rotating shaft 17 slides along the bush 20 and moves in the axial direction. Furthermore, the spline 28 absorbs the axial movement of the rotating shaft 17. Therefore, the axle 15 is pushed down by the pin joint 22 of the rotating shaft 17, and a vertical load is applied to the tire 13. At the same time, when hydraulic pressure is supplied to the hydraulic motor 18, the torque is transmitted to the universal joint 27, the spline 28, and the rotating shaft 17, and then to the pin joint 22 and the axle 15. Therefore, the axle 15 rotates about the vertical central axis 14. The tire 13 rotates around the axle 15 and runs on the specimen 11. Therefore, specimen 11
The repeated driving load of a car is applied to the vehicle. Therefore, this device can test the fatigue life of the specimen 11 against repeated driving loads of an actual automobile, and can obtain accurate test data.

Further, when the axle 15 is rotated around the vertical central axis 14, the tires 13 run alternately over the three specimens 11. Therefore, each specimen 11
can be tested for fatigue at the same time, increasing efficiency and
Test time can be shortened. It is also possible to rotate the axle 15 at high speed and apply high-speed repetitive loads to the specimen 11.

Note that in this embodiment, the hydraulic actuator 1
Although a vertical load is applied to the tire 13 using the hydraulic actuator 16, other load mechanisms such as a weight or a screw rod may be used instead of the hydraulic actuator 16. Instead of the hydraulic motor 18, other rotational drive mechanisms such as an electric motor may be used.

(f) Effects As explained above, in the present invention, a test object can be subjected to repeated driving loads of an automobile.
Therefore, it is possible to test the fatigue life of the specimen under the repeated driving load of an actual automobile.
It is possible to achieve the intended purpose.

[Brief explanation of drawings]

FIG. 1 is a front view showing an embodiment of the present invention, FIG. 2 is a plan view of the soil tank shown in FIG. 1, and FIG. 3 is a front view of a conventional device. DESCRIPTION OF SYMBOLS 11... Specimen, 13... Tire, 14... Vertical central shaft, 15... Axle, 16... Hydraulic actuator, 18... Hydraulic motor.

Claims (1)

[Claims] 1 disposing wheels of a motor vehicle laterally spaced apart from a vertical central axis, supporting the wheels rotatably about the axle and rotatably guiding the axle about the vertical central axis; A load mechanism applying a vertical load to the wheel is located substantially on the vertical central axis and is coupled to the axle, and a rotary drive mechanism such as a hydraulic motor is located substantially on the vertical central axis and coupled to the axle. The running load device is characterized in that the rotation drive mechanism rotates the axle around the vertical central axis to cause the wheels to travel on the specimen.