JPS6124913Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a rotary bending fatigue testing device that applies a thrust load in the direction of pin removal on the press-fitted portion of a pin into a link in a track link of a caterpillar used in construction machinery, etc. .

There have been reports of track pins press-fitted into track links in caterpillars for construction machinery and the like falling out due to thrust loads during running operation. Therefore, in order to find the optimal press-fit rigidity and surface condition of the fitting part of the track pin into the track link, and to test its durability, simply apply a cantilever load to the track pin and check its condition against bending load. Just looking is not enough.

Conventional fatigue testing equipment for fitting parts, etc. includes a cantilever rotary bending actual axle fatigue testing machine that measures the fatigue strength of fitting parts of railroad axles. Therefore, it cannot be said that it is suitable as a fatigue tester for the fitting part between a track link and a pin, which is subjected to both thrust load and bending load as described above.

The present invention reproduces the load condition of the pin press-fit part of a track link that receives both thrust load and bending load at the same time, and while applying repeated loads,
The purpose is to provide a testing device for testing the fatigue strength, durability, etc.

In order to achieve this purpose, the fatigue test device for a track link press-fit part of the present invention is a rotary bending test device in which a radial load is applied to the track pin while rotating a test piece of a press-fit combination of a track link and a track pin. A shaft is provided by hollowing out the center of the rotating main shaft which is integrally equipped with a test piece mounting jig for holding the test piece, and a thrust load is applied to the pin in the pin extraction direction by the shaft. This makes it possible to conduct a fatigue test while simultaneously applying two loads: a thrust load and a bending load.

In addition, the test piece mounting jig, which is integrally attached to the rotating main shaft, has been devised so that the test piece can be mounted in an adjustable manner, making it possible to mount an actual track link test piece, allowing for highly accurate testing. is becoming possible.

Preferred embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show the entire test apparatus according to an embodiment of the present invention. In the figure, numeral 1 indicates a test piece in which a track pin 2 is press-fitted into a track link 3, and is fixedly attached to a test piece mounting jig 4.
The test piece mounting jig 4 is attached to the rotating main shaft 5 and rotates together with the rotating main shaft 5. The rotating main shaft 5 is provided with a pulley 6, which is connected via a belt 7 to a pulley 9 of a motor with a reduction gear, which is a rotation driving means 8, and the rotating main shaft 5 is rotated by the motor 8.

A hole 10 extending in the axial direction is provided through the interior of the rotating main shaft 5, and a pusher rod 11 is inserted into the hole 10. Pushyarod 1
One end of the test piece 1 passes through a hole in the test piece mounting jig 4 and abuts on the track pin 2, and the other end is mounted on a thrust load pressurizing slide table 13 that is slid by a thrust load pressurizing handle 12. Load cell 1
The thrust force is received from the 4th axis. Note that 15 is a tachometer sensor, and 16 is a counter sensor, which can count the number of rotations of the rotating main shaft 5 and display it on a counter 17.

On the other hand, a bearing 18 is fitted at or near the tip of the cantilever of the track pin 2.
A bearing case 19 holding the bearing 18 is supported by a bending load applying means 20 that applies a pressing force in a direction perpendicular to the axial direction of the track pin 2 and applies a bending load to the pin 2. In addition, 21 is a fulcrum length adjustment handle, and by rotating this, the pressurizing means 20 can be moved in the direction parallel to the axial direction of the pin 2, and the load point to which the bending load is applied can be changed. Reference numeral 22 denotes a radial load pressure handle, and by rotating the handle 22, the radial load applied to the track pin 2 in the direction perpendicular to the track pin axis can be set to any value.

3 and 4 show how the test piece 1 is attached to the test piece attachment jig 4. FIG. That is, the track link 3 is fixed by adjusting its position with bolts 23 from all sides, and the mounting jig 4 is fixed to the end flange portion of the rotating main shaft 5 with bolts 24.

Next, a fatigue test using the above device will be explained.

First, the test piece 1 is positioned using the bolt 23 and fixed to the test piece mounting jig 4, and then this is mounted on the rotating main shaft 5.

Next, the handle 12 is rotated to apply a necessary thrust load to the track pin 2 while observing the load meter 14, and the handle 22 is rotated to adjust the bending load applied to the track pin 2.

Subsequently, the motor 8 is rotated, the rotating main shaft 5 is rotated, and the test piece 1 is rotated together with the rotation of the rotating main shaft 5. A thrust load is simultaneously applied to the press-fitted portion of the track pin 2 into the track link 3, and a repeated bending load is applied thereto. The number of repeated loads is read by a counter 17 to check fatigue resistance and durability.

As mentioned above, when using the track link press-fit part fatigue testing device of the present invention, since the pin extraction force and the bending force are applied simultaneously, the actual condition of the track link can be reproduced, and the track link press-fit part can be tested with high accuracy and reliability. Can perform high fatigue tests.

Further, if the track link is attached to the mounting jig by fixing it from all sides using bolts that fix the track link, it becomes possible to realize the mounting using each link although there are various types of track links.

In the above description, the track link press-fitted part was taken as an example, but it goes without saying that the present invention can also be applied to testing the phenomenon of pulling out of the fitted part in other machines.

[Brief explanation of the drawing]

FIG. 1 is a front view of a fatigue testing device according to an embodiment of the present invention, FIG. 2 is a plan view of the device shown in FIG. 1, and FIG.
The figure is a side view of the apparatus shown in FIG. 1 near the test piece mounting jig, and FIG. 4 is a front view of the jig shown in FIG. 3. DESCRIPTION OF SYMBOLS 1... Test piece, 2... Track pin, 3... Track link, 4... Test piece mounting jig, 5... Rotating main shaft, 6... Pulley, 8... Rotating drive means, 1
0... Hole, 11... Push rod, 12... Thrust load pressure handle, 14... Load cell, 17
...Counter, 18...Bearing, 20...Bending load pressurizing means, 22...Radial load pressurizing handle, 23...Bolt.

Claims (1)

[Scope of utility model registration request] a rotating main shaft integrally provided with a test piece mounting jig for holding a test piece of a track link press-fit portion in which a pin is press-fitted into the link; a rotation driving means for rotating the rotating main shaft about its axis; and a rotating main shaft. a push rod that passes through a hole hollowed out in the axial direction and has one end abutted against the pin to apply a thrust load to the pin; and a bending load application that applies a load to the pin in a direction perpendicular to the axial direction of the pin via a bearing. A fatigue test device for a track link press-fitted part, which is comprised of a pressure means and a press-fitted part of a track link.