JPS5845178Y2 - Track sealing device - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a crawler track sealing device.

When the endless track is driven, if sand or the like erodes between the pins and bushings that connect the links, they act as abrasives and abrade the surfaces of the pins and the inner surfaces of the bushes.

When this pin and bushing wear out, the spacing between the pins is distorted and the ring stretches, it does not mesh properly with the teeth of the starting wheel that starts it, causing abnormal wear of the teeth of the starting wheel, and the teeth of the starting wheel engage violently, causing the endless track. This will significantly shorten the overall lifespan.

Various crawler sealing devices have been used to prevent the above, but each has the following drawbacks.

Figure 1 shows an outline of an endless track.

The neighbor links 1.2 are connected by a bush 3 button and a pin 4.

FIG. 2 is a cross-sectional view of the connecting part, in which the bush 3 is fitted into the fitting hole of the inner link 2, the pin 4 is passed through the bush 3,
The protruding end is fitted into the fitting hole of the outer link 1, and the link 1
, 2 are concatenated.

A sealing material is applied to the annular recess 5 formed on the inner outer periphery of the fitting hole of the pin 4 in the link 1 to seal it.

2 and 3 show conventional sealing materials. In FIG. 2, a sealing material that combines polyurethane rubber 6a and foamed urethane 6b, which have relatively good sealing properties, is used.
The figure uses a disc spring 7.

The sealing material shown in Figure 2 has good sealing performance but is soft, so when the vehicle runs on a slope and lateral force is applied to the link, it deforms and breaks off. Although it was acceptable, the sealing performance was poor because the sealing surface was in line contact with metal.

In addition, both seals do not have a sealing effect against oil and grease, so lubricant cannot be inserted between the pin and the bushing, causing premature wear due to metal contact, or causing a squeaking sound when the track moves, causing the operation It was making people feel uncomfortable.

Therefore, the object of the present invention is to provide a crawler sealing device that eliminates the above-mentioned drawbacks, creates a seal that can be received laterally, has good sealing properties against oil, etc., and prevents wear of pins and bushings. Its feature is that the part that receives lateral force and the seal part are separated from each other,
The seal lip part is equipped with a seal that can be loaded with an auxiliary ring, and a lubricant is applied between the pin and bushing to prevent wear.

This crawler sealing device can be applied to bulldozers, tractor excavators, and power shovels that have crawler tracks attached.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described in detail below with reference to the drawings.

Figure 4 shows a cross section of a seal used in the crawler sealing device of the present invention, and shows an annular ring seal 8 made of a relatively hard material with wear resistance and elasticity, such as hard urethane rubber, and a wear-resistant seal 8. An annular backup ring with a pentagonal cross section made of rubber such as nitrile rubber 9
It is composed of a combination of

The seal 8 has a heel portion 81 and a lip portion 82 formed by a groove a.
Consists of individual parts.

The lip portion 82 is slightly inclined and longer than the heel portion 81 by the dimension t, and has an acute angle 83 formed at its tip.

FIG. 5 shows the seal installed in the annular recess 5 of the link 1.

Since the length of the space formed by the link 1 and the bushing 3 is the same as the length of the heel part 81 of the seal 8, the lip part 82 deforms inward, and the acute angle part 83 of the lip part 82 touches the end surface 31 of the bushing. It is pressed by the restoring force of the lip portion 82.

Also, since the dimension of the bank amplifier ring 9 is larger than that of the recess 5 by t, it is compressed when assembled and has resilience, so that it always follows the lateral movement of the bush 3 and the lip portion 81
is brought into close contact with the bush end face 31.

In addition, the heel portion 82 bears the load in the lateral direction,
The lip portion 82 is prevented from being deformed more than necessary due to excessive Z force, and is brought into close contact with the bush end face 31 with an appropriate pressing force.

A gap 10 of 0.2 to 0.6 rran is provided between the bush 3 and the pin 4, and a small amount of an antioxidant and an extreme pressure agent are added, or a high viscosity lubricating oil or grease is sealed.

The present crawler sealing device configured in this manner has a lip portion 82.
Due to its own elasticity and the restoring force of the bank up ring 9, its acute angle portion 83 is brought into close contact with the bush end face 31 with appropriate force, thereby preventing internal oil from leaking out, and the heel portion 81 receiving lateral loads. prevents invasion of foreign objects from outside.

Therefore, since the pin 4 and the bush 3 are always lubricated with the sealed lubricant, they do not wear out, extending the life of the crawler track, and do not make unpleasant squeaking noises.

As described above, according to the present invention, the annular seal is made of a relatively hard material that has wear resistance and elasticity, and has a heel portion and a lip portion that is slightly longer than the heel portion, and an elastic material that extends slightly beyond the seal. and a backup ring made of a material such as rubber having elastic properties, and housed in the concave part of the link in a compressed state so that the lip part of the seal comes into close contact with the end face of the bushing and forms the main sealing surface, A gap of 0.2 to 0.6 mm is provided between the pin and the bushing, and a high-viscosity lubricant is filled in, which allows for lateral loads to be supported. It is possible to prevent wear and extend the life of the track.

[Brief explanation of drawings]

Fig. 1 is a schematic perspective view of an endless track, Figs. 2 and 3 are sectional views of main parts showing an example of a conventional crawler sealing device, and Fig. 4 is a diagram showing the structure of a seal used in the crawler sealing device according to the present invention before installation. FIG. 5 is a sectional view of the main part of the present crawler sealing device. 1.2...Link, 3...Butshu,
31... Bush end face, 4... Pin,
5...--Concave portion, 8... Annular seal 81
... Heel part, 82 ... Lip part, 8
3...Acute corner, 9...Backup ring X10...Gap.

Claims (1)

[Scope of utility model registration request] An annular seal made of a relatively hard material with wear resistance and elasticity, with a heel and a slightly longer lip, and a resilient material such as rubber that extends slightly beyond the seal. The bank-up ring is assembled with a bank-up ring, and is housed in the concave part of the link in a compressed state so that the seal luff part comes into close contact with the end face of the bushing to form the main sealing surface, and a gap is provided between the pin and the bushing, and the seal is inserted into the gap. A crawler sealing device characterized by containing a high viscosity lubricant.