JP2002127957A - Track roller for crawler vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent entering of stain substance in a sliding part between a roller and a roller shaft for supporting the roller. SOLUTION: The roller 30 rolling on a track link 10a of a crawler 10 is rotatably fitted into the roller shaft 31. At both end parts of the roller 30, collars 32 fixed to a track frame 13 of a lower traveling body 1 are fitted. The collar 32 is continuously provided with an annulus ring shaped seal holding part 40 projecting inward to prevent entering of stain substance such as mud from an opening part of a gap formed between the collar 32 and an outer peripheral surface of the roller shaft 31 within the collar 32. An elastic sealing member 41 is mounted in a state bent by prescribed amount between the seal holding part 40 and an end face of the roller shaft 32 and an opening end of the gap is sealed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a track roller, such as a construction machine such as a hydraulic shovel, having a crawler belt and comprising a lower roller and an upper roller rolling along a link member of the crawler belt. It is.

[0002]

2. Description of the Related Art FIG. 5 shows a hydraulic shovel as an example of a construction machine. In the drawing, reference numeral 1 denotes a lower traveling structure, on which an upper revolving structure 2 is installed so as to be capable of revolving. An operator rides on the upper revolving structure 2 to perform operations. And a front work machine 4 is mounted. Front work machine 4
Is a boom 4a provided on the upper swing body 2 so as to be capable of raising and lowering.
And an arm 4b connected to the tip of the boom 4a so as to be rotatable in a vertical direction. A bucket 4c, for example, is detachably attached to the tip of the arm 4b as a front attachment.

The undercarriage 1 has a crawler belt 10 having a track link 10a connected endlessly. The crawler belt 10 is provided to be wound between a driving wheel 11 and a driven wheel 12, and the driving wheel 11 is hydraulically driven. When the crawler belt 10 is sent by being rotated by a motor, the vehicle travels. Drive wheel 11
And the driven wheels 12 are provided so as to be connected to a track frame 13 constituting the undercarriage 1, and a lower surface of the crawler belt 10 is secured between the drive wheels 11 and the driven wheels 12. The lower roller 14 and the upper roller 1
5 are provided.

FIG. 6 shows a cross section taken along line AA of FIG. In the figure, reference numeral 20 denotes a roller (lower roller 14 or upper roller 1).
5), a shaft insertion hole 20a is formed in the roller 20, and a roller shaft 21 is inserted through the shaft insertion hole 20a. Collars 22 are fitted to both ends of the roller shaft 21. The collar 22 and the roller shaft 21 are
The rollers 23 are connected so as to be substantially integral with each other by pins 23 mounted so as to penetrate in a direction perpendicular to the axis of the roller shaft 21. The collar 22 is fixed to the track frame 13 by welding or the like. Here, the roller 20 is not directly fitted to the roller shaft 21, but a bush 24 for smooth sliding between them is interposed. In order to smoothly rotate the roller 20 with respect to the roller shaft 21 via the bush 24, lubricating oil is sealed therebetween. An oil reservoir 25 is formed to store the lubricating oil. This oil sump 25
Consists of an annular concave portion formed on the inner surface of the intermediate portion of the roller 20, and the bush 24 is divided into right and left at the position of the oil reservoir 25.

Further, in order that the lubricating oil film in the above-mentioned sliding portion extends over the entire circumference of the roller shaft 21, an oil hole 26 is formed in the roller shaft 21 so as to penetrate vertically. On the outer peripheral surface of the roller shaft 21, one or a plurality of oil paths 27 extending in the axial direction are formed. In order to prevent the lubricating oil from leaking to the outside, and to prevent foreign matter including earth and sand, rainwater, mud, and the like from entering from the outside, the outer peripheral surface of the roller shaft 21 and the inner surface of the collar 22 are formed. In between, an O-ring 28 is provided at a position outside the oil path 25 described above. A floating seal 29 is interposed between the collar 22 and both end surfaces of the roller 20.

[0006]

However, in construction machines that operate outdoors such as hydraulic excavators, there are water and mud, for example, where the roadbed itself is muddy or muddy due to rain. Work is performed even in a severe site, and therefore, the lower traveling body 1 may travel with the ground contact portion of the crawler belt 10 submerged in water or mud. There is a slight gap in the fitting portion of the collar 22 to the roller shaft 21, and there is a possibility that mud may enter the gap between the roller shaft 21 and the collar 22. An O-ring 28 is provided between the roller shaft 21 and the collar 22, and the sliding portion of the roller 20 is sealed, so that pollutants such as water, mud, earth and sand, and dust can directly slide on the roller 20. Although there is no danger of entering the surface, the mud and the like that have entered the gap are not discharged to the outside, but are sealed in the vicinity of the O-ring 28 and stay there, and further mud and water are removed from this state. When it enters, the O-ring 28 is pressed. As described above, when the vehicle travels with a large amount of mud or water entering the gap, loads in various directions act on the fitting portion between the roller shaft 21 and the collar 22, and the retained fouling substance is removed. Further, the O-ring 28 may be pressed, damaging the O-ring 28, deteriorating the sealing function, and eventually getting over the O-ring 28. As a result, inconveniences such as contamination of the lubricating oil filled therein, and solid matter such as earth and sand biting into the sliding portion of the roller 20, causing the roller 20, the roller shaft 21 and the bush 24 to be worn. Will happen.

[0007] The present invention has been made in view of the above points, and an object of the present invention is to reliably prevent a fouling substance from entering between a roller and a roller shaft. .

[0008]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention is directed to a driving wheel and a driven wheel which are connected to a frame of a lower traveling body as a traveling means, and a driving wheel and a driven wheel are provided. A roller shaft provided on a crawler-type vehicle provided with a crawler belt provided between the driving wheel and the driven wheel, and both ends of which are supported by the frame by collars; Is fitted between the two collars,
A track roller having a roller that rolls along the crawler belt, wherein an open end of a gap between an outer peripheral surface of the roller shaft and an inner surface of the collar is provided between the collar and an end of the roller shaft. The feature is that a sealing means for sealing is provided.

Here, the sealing means covers the opening end of the gap between the roller shaft and the collar, whereby the O-ring interposed in the gap between the roller shaft and the collar is not necessarily provided. Good, but sometimes a pin is inserted to connect between the roller shaft and the collar.Therefore, there may be some gaps in the pin insertion part, and the partitioning area of lubricating oil is formed in the first place. It is desirable to attach an O-ring in order to exert its function. As a result, the sealing area of the lubricating oil is double-sealed by the O-ring and the sealing means, so that the lubricating oil can be almost completely prevented from coming into contact with the outside air including moisture, and the deterioration thereof can be prevented. Is suppressed, and the life of the lubricating oil can be extended.

As a specific configuration of the sealing means, for example, an annular seal holding portion having an inner diameter smaller than the outer diameter of the roller shaft is provided at the end of the collar, and the seal holding portion and the end surface of the roller shaft are connected. A configuration in which a ring-shaped elastic seal is mounted between them can be adopted. In this case, a small-diameter projecting portion smaller than the inner diameter of the elastic seal can be formed at the end of the roller shaft, and the elastic seal can be fitted to the small-diameter projecting portion. Alternatively, the collar may be formed in a cap shape, and the end face of the roller shaft may be covered by the lid of the collar.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, FIGS. 1 and 2 show a first embodiment of the present invention. Here, FIG. 1 shows a cross section of the entire configuration of the track roller, and FIG. 2 shows an enlarged view of a main part of FIG. Note that there is no particular difference in the overall configuration of the hydraulic excavator from that of the above-described conventional technology, and in the following description, members that are the same as or equivalent to those of the conventional technology are denoted by the same reference numerals, and A detailed description of is omitted.

In these figures, 30 is a roller, 31
Indicates a roller shaft, and 32 indicates a collar. Roller 30
The left and right sides have a large-diameter rolling portion 30R, and a small-diameter connecting portion 30C between both rolling portions 30R. The roller 30 is provided on a track link 10 a constituting the crawler belt 10, and the claw portion 10 meshes with the drive wheel 11.
It rolls at positions on both left and right sides of b. Roller 30
Has a shaft insertion hole 3 having a predetermined hole diameter at its rotation center.
The bush 33 is inserted into the shaft insertion hole 30a, and the roller shaft 3 is inserted into the bush 33.
1 is slidably mounted. The bush 33 is fitted in the roller 30 in a substantially tight fit state. Therefore, when the roller 30 rotates, the bush 33 slides on the roller shaft 31.
You may make it slidable also with respect to zero. Roller shaft 3
A collar 32 fixed to the track frame 13 is fitted to both ends of the roller shaft 31 in order to support the roller frame 1 on the track frame 13.
A pin 34 is inserted from the collar 32 to the roller shaft 31 in a direction orthogonal to the axis of the collar 32 to prevent the roller shaft 31 from slipping off the roller shaft 2. Further, an oil reservoir 35 is provided between the roller 30 and the roller shaft 31, and an oil hole 36 is formed so as to penetrate the roller shaft 31, and an oil path 37 is formed on the outer peripheral surface. In order to prevent the leakage of the lubricating oil and the intrusion of fouling substances from the outside, which defines the enclosing area of the lubricating oil, a gap is formed between the outer peripheral surface of the roller shaft 31 and the inner surface of the roller 30. An O-ring 38 is provided, and a floating seal 39 is interposed on a joint surface between the end of the roller 30 and the collar 32.
In this respect, there is no particular difference from the above-mentioned prior art.

Here, the end surface of the roller shaft 31 is
2, the collar 32 is integrally provided with an annular seal holding portion 40 projecting toward the end face of the roller shaft 31. Then, the seal holding unit 40
A ring-shaped elastic seal member 41 is provided between the roller shaft 31 and the end face of the roller shaft 31. The elastic seal member 41 is formed of rubber or the like having a rectangular cross section, is sandwiched between the seal holding portion 40 and the end face of the roller shaft 31, and is mounted so as to be compressed by a predetermined amount. As a result, the elastic seal member 41 is pressed against the inner surface of the seal holding portion 40 and the end surface of the roller shaft 31 while the outer peripheral surface is
2 is pressed against the inner surface. As a result, the opening end of the slight gap formed between the collar 32 and the roller shaft 31 is sealed, and the elastic seal member 41 and the seal holding portion 40 that holds the elastic seal member 41 are used. A sealing means for sealing the open end of the gap is provided.

Here, the elastic seal member 41 provided between the collar 32 and the end face of the roller shaft 31
The O-ring 38 has a function different from that of the O-ring 38 interposed between the outer peripheral surface 1 and the inner surface of the collar 32. That is, the O-ring 38 basically forms a storage portion of the lubricating oil sealed between the O-rings 38 on both the left and right sides to prevent the lubricating oil from leaking out. This is for preventing the lubricating oil from being contaminated by an external contaminant such as water, earth and sand, and dust having a small particle size. On the other hand, the elastic sealing member 41
Is to seal the open end of the gap in order to prevent a fouling substance such as muddy water from entering the gap between the roller shaft 31 and the collar 32.
1 is at least partially exposed to the outside. As a result, even if the roller 30 sinks into the mud or the like, there is no possibility that the mud or the like enters the gap between the roller shaft 31 and the collar 32.

Accordingly, the O-ring 38 defines a region in which the lubricating oil supplied to the sliding portion between the roller shaft 31 and the roller 30 is enclosed, and a portion in which the lubricating oil is enclosed from the outside. Regrets its original function of preventing the entry of fouling substances.
In addition, since there is no direct contact of fouling substances including earth and sand from the outside, the durability is improved. Therefore, the O-ring 38 can be maintained in the state of exhibiting the above-described function for a long period of time, and the lubricating ability of the sliding portion during rotation of the roller 30 does not decrease over a long period of time. Rotation can be secured, and the life of the track roller can be extended.

Here, since the pin 34 is inserted so as to penetrate the roller shaft 31 from the collar 32, even if the insertion portion of the pin 34 is made to be substantially tightly fitted, moisture is contained. It is not possible to completely prevent air from entering. By the action of the O-ring 38 disposed inside the mounting position of the pin 34, it is possible to prevent moisture-containing air from entering from outside into the sealed area of the lubricating oil. Therefore, it is not always necessary to mount the pin 34 in a tightly fitted state, and the pin 34 can be mounted so that the pin 34 is dropped from above. It should be noted that if there is a gap in the insertion portion of the pin 34, there is no possibility that a contaminated material including mud or the like may enter, but even if the soil enters through this gap, the gap opens downward. Therefore, when the roller 30 escapes from the mud without staying in the gap, the contaminated material is discharged by its own weight.

Next, FIG. 3 shows a second embodiment of the present invention. In the present embodiment, a small-diameter protrusion 131 a is provided to extend on the end surface of the roller shaft 131, and the outer diameter of the small-diameter protrusion 131 a is equal to the inner diameter of the seal holding portion 40 connected to the collar 32. It is smaller. The elastic seal member 141 interposed between the end face of the roller shaft 131 and the seal holding portion 40 provided on the collar 32 is fitted to the small-diameter projecting portion 131a. Therefore, the elastic seal member 141 is formed by the small-diameter projecting portion 131a and the seal holding portion 4
Only the portion corresponding to the diameter difference from 0 is exposed to the outside, and the other portions are in contact with the end surface of the roller shaft 131, the outer peripheral surface of the small diameter projecting portion 131a, the inner peripheral surface of the collar 32, and the inner surface of the seal holding portion 40. I have. Accordingly, when the elastic seal member 141 is mounted in a compressed state, the elastic seal member 141 is pressed against the above-described surfaces, so that the gap between the outer peripheral surface of the roller shaft 131 and the inner peripheral cotton of the roller 30 is sealed against the open end. Function is improved more.

FIG. 4 shows a third embodiment of the present invention. In this embodiment, the collar 232 fitted to both ends of the roller shaft 31 is
The shape is a closed cap having a. Therefore, the collar 232 not only surrounds the outer peripheral surface of the roller shaft 31 but also is mounted so as to cover the end surface of the roller shaft 31. With this configuration, the color 2
The opening end of the gap between the roller shaft 32 and the roller shaft 31 is completely closed. As a result, even if the roller 30 is completely buried in the mud or the like, it is possible to completely prevent muddy soil, water, or air containing moisture or the like from entering the gap. As described above, the collar 232 is fitted to the end face of the roller shaft 31, but the collar 232 is fitted from the end of the roller shaft 31.
Even when the track roller is closed, there is no hindrance when assembling the track roller. Although not essential, it is desirable that the cover 232 a of the collar 232 have a predetermined gap with respect to the end surface of the roller shaft 31.

[0019]

Since the present invention is constructed as described above, it is possible to reliably prevent a contaminant from entering between the roller and the roller shaft, to prevent contamination of the lubricating oil sealed between the rollers and the roller and the roller. When a seal member such as an O-ring is attached to the shaft so as not to be damaged and further to form a sealed portion for lubricating oil between the outer peripheral surface of the roller shaft and the inner surface of the collar, the seal member is used. And the like can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a track roller according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a sectional view similar to FIG. 2, showing a second embodiment of the present invention.

FIG. 4 is a sectional view similar to FIG. 1, showing a third embodiment of the present invention.

FIG. 5 is an overall configuration diagram of a hydraulic shovel as an example of a traveling vehicle equipped with track rollers.

6 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper revolving structure 10 Crawler belt 11 Drive wheel 12 Follower wheel 13 Track frame 14 Lower roller 15 Upper roller 30 Roller 31, 131 Roller shaft 32, 232 Collar 34 Pin 40 Seal holding part 41, 141 Elastic seal member 131a Small diameter Part 232a Lid part

Claims (4)

[Claims] 1. A crawler-type vehicle comprising, as a traveling means, a drive wheel and a driven wheel connected to a frame of a lower traveling body, and a crawler track wound between the drive wheel and the driven wheel. Is provided between the drive wheel and the driven wheel, a roller shaft whose both ends are supported by a collar on the frame, and fitted at a position between the collars of the roller shaft,
A track roller having a roller that rolls along the crawler belt, wherein between a collar and an end of the roller shaft, an opening end of a gap between an outer peripheral surface of the roller shaft and an inner surface of the collar is sealed. A track roller for a crawler-type vehicle, characterized in that a sealing means is provided. 2. The sealing means is provided with an annular seal support portion having an inner diameter smaller than the outer diameter of the roller shaft connected to an end portion of the collar, and between the seal support portion and an end surface of the roller shaft. The track roller for a crawler-type vehicle according to claim 1, wherein an annular elastic seal member is mounted on the track roller type vehicle. 3. An end portion of the roller shaft is provided with a small-diameter projecting portion smaller than the inner diameter of the elastic seal, and the elastic seal is provided by being fitted to the small-diameter projecting portion. A track roller for a tracked vehicle according to claim 2. 4. The sealing means is characterized in that the collar is formed in a cap shape having a lid, and the end surface of the roller shaft is covered with the lid of the collar. A tok roller for a crawler-type vehicle according to claim 1.