JPS594860Y2 - Track dust seal - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of a crawler dust seal used in the crawler tracks of a tracked vehicle.

In general, this type of track dust seal has the function of preventing the lubricating oil sealed in the pin from leaking, as well as preventing foreign matter such as earth and sand from entering.Many conventional dust seals have elastic Sealing is achieved by pressing the lip of the seal ring made of body against the end surface of the bushing.

However, with this structure of the dust seal, if a minute foreign object enters the sliding contact area, the elastic seal ring continues to make sliding contact with the end face of the bushing while grasping the foreign object, which accelerates the wear of the sliding contact surface. As a result, an annular groove is formed on the end surface of the bush.

As a result, the sealing effect of the sliding contact area decreases and the lubricating oil is significantly consumed. At the same time, dirt and other substances can enter between the pins and bushings, causing seizure between them and shortening the life of the track. This is the cause of the decline.

In addition, when the annular groove formed on the end face of the bushing is disassembled and reassembled for repair, or when the bushing is reversed and reused, the desired sealing effect cannot be obtained even if a new dust seal is used. There is a problem.

This invention was made with the aim of improving this problem, and is intended to provide a lubricating oil seal and a crawler dust seal that prevents foreign matter from entering, with a simple structure, without providing any sliding parts.

This invention will be described in detail below with reference to an illustrated embodiment.

In the figure, 1 and 2 are links constituting the crawler track, and the end of a bushing 3 is press-fitted into the inner end of one link 1, and the end of a bushing 3 is inserted into the outer end of the other link 2. Both ends of the pin 4 are press-fitted and fixed.

A passage 4a for sealing lubricating oil is formed in the center of the pin 4, and the lubricating oil sealed in this passage 4a is supplied between the pin 4 and the bushing 3 through a through hole 4b. At the same time, an annular counterbore 2a is formed on the side surface of the bush 3 of the link 2 so as to surround the pin 4, and the crawler belt dust seal 5 of this invention is housed in the counterbore 2a.

The crawler dust seal 5 is attached to the bushing 3 as shown in FIG.
A thrust ring 6 whose one end is fitted into an annular portion 3a formed on the end face of the thrust ring 6, a fixed ring 7 which has a larger diameter than this thrust link 6 and which is fitted into the bottom of the counterbore 2a, and these thrust rings 6. It is comprised of a sealing member 8 made of a flexible tube that connects between the fixing rings 7.

The sealing member has oil resistance, and the inner circumferential surface on one end is liquid-tightly fixed to the outer circumferential surface of the thrust ring 6 by means of adhesive or vulcanization, and the outer circumferential surface on the other end The surface is fluid-tightly secured to the inner circumferential surface of the fixed ring by similar means.

When assembling the counterbore 2a into the counterbore 2a, as shown in FIG. At the same time, the end of the thrust ring 6 is press-fitted or bonded to the annular portion 3a of the end surface of the bush 3 in a fluid-tight manner, and assembled in the state shown in FIG.

As described in detail above, this invention fixes one of the thrust rings 6 constituting the crawler dust seal 5 to the bushing 3 side, and fixes the fixing ring 7 to the inner bottom of the counterbore 2a. A sealing member 8 that is continuous between
The lubricating oil seal is designed to prevent the intrusion of foreign substances such as earth and sand, and since it does not have any sliding contact parts, there is no risk that the sliding contact parts will wear out and the sealing effect will deteriorate prematurely.

In addition, since the sealing member 8 twists and absorbs the mutual rotation of each link 1 and 2, there is no impediment to the rotation of each link 1 and 2, and the load in the thrust direction is received by the thrust ring 6. Therefore, there is no fear that the seal member 8 will be damaged by the thrust load.

In addition, two rings 6.7 and a tubular seal member 8 are included.
Since the entire structure can be constructed with only one piece, it is easy to manufacture and can be provided at low cost.

[Brief explanation of drawings]

The drawings show an embodiment of this invention, with FIG. 1 being a sectional view of the assembled state, FIG. 2 being a sectional view of the crawler dust seal, and FIG. 3 being a sectional view of the assembly process. 1 and 2 are links, 2a is a counterbore, 3 is a bush, 4 is a pin, 6 is a thrust ring, 7 is a fixed ring, 8
is a seal member.

Claims (1)

[Scope of utility model registration request] In a system in which the links 1 and 2 constituting the crawler track are connected to each other by a bushing 3 and a pin 4 inserted through the bushing 3, a thrust ring 6, which is fitted liquid-tightly to the end surface of the bushing 3, is connected to the link. A fixing ring 7 that is fluid-tightly fitted to the inner bottom surface of the counterbore 2a formed on the side end surface of the bush 3
A crawler dust seal consisting of a tubular seal member 8 which is fluid-tightly connected between the rings 6 and 7.