JP2000247270A - Crawler belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continuously supply lubricating oil to a seal member and prevent the lubricating oil from leaking outside. SOLUTION: An outer link part 9 of a track link 8 constituting a crawler belt 7 is provided with a seal mounting hole 9B, and a sealing device 21 for sealing between an inner end face 9C of the outer link part 9 and an end face 11A of a bush 11 is mounted in the seal mounting hole 9B. The sealing device 21 is composed of an annular seal 22 formed of spring steel of nearly V-shaped cross section, and an annular porous member 23 formed of porous elastic resin material surrounding the annular seal 22 from the radial outside. The porous member 23 captures lubricating oil G to keep the annular seal 22 in a lubricated state with the lubricating oil G.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crawler belt suitable for use in a tracked vehicle such as a hydraulic shovel and a hydraulic crane.

[0002]

2. Description of the Related Art In general, crawler tracks used in tracked vehicles such as hydraulic shovels have left and right links in which an outer link portion is formed on one side in the longitudinal direction and an inner link portion is formed on the other side in the longitudinal direction. A track link, a bush provided between the inner link portions of the track links, and both left and right ends facing the outer link portion; and a left and right direction inserted into the bush and provided. Are provided with connecting pins whose both end sides are fitted and fixed to the outer link portions, and a sealing device provided between the outer link portions of each of the track links and the bush (Japanese Utility Model Publication No. 50-23945).
No.).

[0003] A crawler belt of this kind in the prior art is provided so as to be wound between an idler wheel and a drive wheel, and the drive wheel is driven to rotate by a traveling hydraulic motor or the like so that the crawler track is connected to the idler wheel and the drive wheel. And the vehicle is driven to move forward and backward.

In this prior art, the sealing device is constituted by two disc springs made of spring steel, for example.
By contacting each of these disc springs with the inner end face of the outer link portion and the end face of the bush, the two are sealed.

[0005] In another prior art, a seal device using an annular rubber seal made of urethane rubber or the like is known (Japanese Utility Model Laid-Open No. 48-27535, Japanese Utility Model Laid-Open No. 49-113342). No.).

A rubber seal according to another conventional technique can receive a thrust load acting between a bush and a track link more favorably than the above-mentioned disc spring, and can enhance the sealing performance between the two. There are advantages such as possible.

[0007]

The prior art described above has a configuration in which each disc spring is brought into line contact with the inner end face of the outer link portion and the end face of the bush. However, since this disc spring is in metal contact with the inner end surface of the outer link portion and the end surface of the bush, unless lubricating oil or the like is supplied to these abutting portions, for example, during the orbiting operation of the crawler belt, etc. There is a problem that not only noise is easily generated but also durability and life are reduced due to wear, seizure and the like.

On the other hand, even when lubricating oil is supplied between the connecting pin and the bush, the lubricating oil is supplied to the outside through the contact portion between the disc spring and the outer link portion and the contact portion between the disc spring and the bush. , The amount of lubricating oil decreases early. In such a state, muddy water or the like easily enters from the outside, and there is a problem that corrosion such as rust occurs on the disc spring and the sealing function is deteriorated.

Further, in a case where a rubber seal is used as in other related arts, when a thrust load is generated between the outer link portion and the bush during, for example, a crawling operation of the crawler belt, the rubber seal and the outer link are used. Since the surface pressure between the portion and the bush is increased, the rubber seal is quickly worn, and the durability and the like are reduced. Further, when earth and sand from the outside enter the contact portion between the rubber seal and the outer link portion and the contact portion between the rubber seal and the bush, respectively,
There is a problem that these contact portions are worn and damaged early, and the sealing performance is reduced.

Further, in recent years, it has become necessary to move such a tracked vehicle from a work site to a place where it can be managed in order to prevent theft. In this case, the transfer of the tracked vehicle by truck requires complicated setup work, so the tracked vehicle itself must travel by itself and be moved to the intended storage location. Has been done.
As a result, the tracked vehicle needs to travel to the storage location in addition to traveling during the on-site work. Therefore, due to an increase in the traveling distance, a large amount of sliding occurs on the seal inserted between the track link and the bush. There is a problem that dynamic resistance acts and it is difficult to secure a sufficient sealing function.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to use a porous member capable of catching lubricating oil, thereby continuously supplying lubricating oil to a seal member. It is another object of the present invention to provide a crawler belt capable of preventing leakage of lubricating oil to the outside, preventing entry of foreign matter from the outside, and improving durability and life of the seal member.

[0012]

In order to solve the above-mentioned problems, a crawler belt according to the present invention has an outer link portion formed on one side in the longitudinal direction and an inner link portion formed on the other side in the longitudinal direction. Left and right track links connected endlessly, a bush provided between inner link portions of the track links, and both left and right ends facing the outer link portion, and a bush inside the bush. And a connecting pin which is provided between the outer link portions of the respective track links and the bush, the left and right ends of the connecting pin being fitted and connected to the outer link portions. And a sealing device provided on the side.

The first aspect of the present invention is characterized in that the sealing device is annularly formed of an elastic material, and is disposed between the inner end surface of the outer link portion and the end surface of the bush with a tight allowance. It is constituted by a seal member and a porous member which is annularly formed of a porous elastic material in order to trap lubricating oil therein and which is elastically deformable between the outer link portion and the bush. .

With this configuration, the space between the outer link portion of the track link and the bush is
The lubricating oil can be sealed while being held by the porous member, and leakage of the lubricating oil to the outside can be prevented, and the lubricating oil can maintain a good lubricating state of the seal member. Further, even if muddy water, earth and sand from the outside intrudes toward the seal member from between the outer link portion and the bush, the infiltration of muddy water and the like can be prevented by the lubricating oil captured by the porous member.

According to a second aspect of the present invention, the porous member is formed as an annular body surrounding the seal member from the outside in the radial direction.
The lubricating oil is sealed between the outer link portion and the bush.

Thus, the porous member can be arranged so as to surround the seal member from the outside in the radial direction.
This porous member can prevent the lubricating oil supplied to the seal member from leaking to the outside, and can prevent muddy water and the like from entering from entering the seal member.

Further, according to a third aspect of the present invention, the porous member includes:
It is configured to be formed of an open-cell porous material in which the porosity is continuously communicated. As a result, the lubricating oil can be uniformly trapped in the porous member through the open cells.

Further, according to a fourth aspect of the present invention, in the seal member, the both ends in the axial direction abut against the inner end surface of the outer link portion and the end surface of the bush, and the intermediate portion in the axial direction has a V-shaped bent portion. It consists of.

With such a configuration, even when a thrust load is applied between the outer link portion and the bush, the annular seal elastically deforms the V-shaped bent portion, thereby forming the inner portion of the outer link portion. Since the end face and the end face of the bush can be elastically pressed, the left and right
The rattling in the right direction can be suppressed. Further, lubricating oil captured by the porous member can be supplied to these contact surfaces, and the contact surfaces can be maintained in a lubricated state.

Further, according to a fifth aspect of the present invention, the seal member is formed of a resin annular seal having an M-shaped cross section, and the porous member is located between the outer link portion and the bush. Are arranged radially inside and outside.

[0021] Even in this case, the lubricating oil can be held around the annular seal by the porous member in a manner substantially similar to the first aspect of the present invention, and the lubricity of the annular seal is improved. be able to.

On the other hand, in the case where the sealing member is constituted by a plurality of disc springs arranged in abutting relationship with each other between the inner end face of the outer link portion and the end face of the bush as in the invention of claim 6, The thrust load acting between the outer link portion and the bush can be stably supported by the plurality of disc springs, thereby preventing left and right rattling between the track links. Can be.

According to a seventh aspect of the present invention, the seal member has a first contact portion that contacts the inner end surface of the outer link portion, and a second contact portion that contacts the end surface of the bush. ,
At least one of the first and second contact portions is provided with an oil groove through which lubricating oil flows.

Thus, the lubricating oil is smoothly guided by the oil groove between the first contact portion of the seal member and the outer link portion, or between the second contact portion of the seal member and the bush. And lubricity between them can be enhanced.

Further, according to the invention of claim 8, the seal member is provided with a through hole through which lubricating oil flows in a space between the outer link portion and the bush. As a result, the lubricating oil can be substantially uniformly introduced into the space through the through-hole of the seal member, and the lubricity of the seal member can be improved in the same manner as the seventh aspect of the present invention.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a case where a crawler belt according to an embodiment of the present invention is applied to a hydraulic shovel will be described in detail with reference to the accompanying drawings.

Here, FIGS. 1 to 7 show a first embodiment of the present invention, wherein 1 is a lower traveling body of a hydraulic shovel,
The undercarriage 1 includes a track frame 2 having left and right side frames 2A (only one is shown) extending in the front-rear direction, and idler wheels provided on both ends of the side frame 2A of the track frame 2, respectively. 3, drive wheel 4
And a crawler belt 7 to be described later wound between the idler wheel 3 and the drive wheel 4.

The side frame 2A of the track frame 2 has an upper roller 5 for guiding the crawler belt 7 above the side frame 2A and a plurality of lower rollers 6, 6 for guiding the crawler belt 7 below the side frame 2A. ,... Are provided.

Reference numeral 7 denotes a crawler belt provided to be wound between the idler wheel 3 and the drive wheel 4. The crawler belt 7 is composed of a track link 8, a bush 11, a connecting pin 12, a shoe 13, and the like, which will be described later. I have. The crawler belt 7 is configured such that a bush 11, which will be described later, located at a connection portion of each track link 8 meshes with the drive wheel 4, and the drive wheel 4 is driven to rotate in this state, so that the idler wheel 3 and the drive wheel 4 The circulating operation is performed between the two.

Reference numerals 8 and 8 denote left and right track links which are disposed facing left and right, and are connected endlessly to each other.
The track link 8 extends along the longitudinal direction of the crawler belt 7. An outer link portion 9 is formed on one side of the track link 8 in the longitudinal direction.
As shown in FIGS. 4 and 5, a pin insertion hole 9A into which the connection pin 12 is inserted, and a seal device 21 to be described later, which is enlarged in diameter from the pin insertion hole 9A toward the bush 11, is mounted. The seal mounting hole 9B to be formed and the inner end face 9C between the pin insertion hole 9A and the seal mounting hole 9B are formed as stepped holes.

On the other side of the track link 8 in the longitudinal direction, an inner link portion 10 is formed.
0 is a bush insertion hole 10A into which the bush 11 is inserted.
Are formed.

Reference numeral 11 denotes an inner link portion 1 of the track link 8.
The bush 11 is provided between 0 and has a connecting pin 12 inserted into the inner peripheral side. The bush 11 is fixed in a bush insertion hole 10A of each of the inner link portions 10 in a press-fit state, and both ends in the axial direction are end faces 11A. , 11A.

Reference numerals 12, 12,... Denote connecting pins that connect the adjacent track links 8, 8 with each other by pinning. The connecting pins 12 are inserted into the bush 11 with a small gap, and both ends in the left and right directions. The side is press-fitted into the pin insertion hole 9A of the outer link portion 9. In addition, a gap of, for example, about 0.1 to 0.5 mm is secured in the radial direction between the connecting pin 12 and the bush 11, and the gap is filled with lubricating oil G. Is smoothly rotated relative to the bush 11.

Reference numeral 13 denotes a shoe made of a metal plate provided on the left and right track links 8, 8.
As shown in FIG. 4, it is fixed to the outside of each track link 8 (the outer peripheral side of the crawler belt 7), and integrally connects the left and right track links 8, 8, and forms a ground surface of the crawler belt 8.

Reference numerals 21 and 21 denote left and right seal devices provided between the outer link portion 9 of the track link 8 and the bush 11 and provided on the outer peripheral side of the connecting pin 12. The seal device 21 will be described later. And an annular seal 22 and a porous member 23.

Reference numeral 22 denotes a V-shaped annular seal (hereinafter referred to as an annular seal) as a seal member disposed between the outer link portion 9 and the bush 11 and located on the outer peripheral side of the connecting pin 12. As shown in FIG. 5, the seal 22 is formed of a metal material such as spring steel or the like as an annular body having a substantially V-shaped bent portion 22A at an intermediate portion in the axial direction.

The annular seal 22 elastically abuts on the inner end surface 9C of the outer link portion 9 with an interference with the first contact portion 22B and the end surface 11A of the bush 11 with the interference. A second contact portion 22 </ b> C is in contact with the outer link portion 9 and the bush 11 is sealed by the contact portions 22 </ b> B and 22 </ b> C.

The annular seal 22 receives a thrust load acting between the track links 8 as described later, so that the outer link portion 9 and the inner link portion 10 play back in the axial direction or rotate. This is to prevent rattling in the direction.

An annular porous member 23 is provided on the outer peripheral side of the annular seal 22 so as to be elastically deformable between the outer link portion 9 and the bush 11.
Is annularly formed of a porous elastic resin material using a high-performance resin such as urethane rubber or polyamide. The porous member 23 is formed as an annular body surrounding the annular seal 22 from the outside in the radial direction, and the lubricating oil G is captured inside the annular member 23.

Here, the porous member 23 is formed of an open-celled porous material in which the above-mentioned porosity communicates continuously, that is, an elastically deformable sponge-like material (sponge-like material). For this reason, the lubricating oil G is uniformly trapped in the entire inside of the porous member 23 through the open cells.

The porous member 23 is connected to the outer link 9
A housing space 24 for housing the annular seal 22 is defined between the inner end surface 9C and the end surface 11A of the bush 11,
The lubricating oil G is sealed in the housing space 24.

As shown in FIG. 7, when the volume of the housing space 24 is reduced for a reason to be described later, the porous member 23 absorbs and captures the lubricating oil G in the housing space 24, and When the volume of the storage space 24 is increased as shown in FIG. 6, the lubricant G trapped in the porous member 23 is discharged into the storage space 24, and the lubricant G G is supplied between the outer link portion 9 and the contact portion 22B of the annular seal 22, and between the bush 11 and the contact portion 22C of the annular seal 22.

An upper revolving unit 25 is provided on the lower traveling unit 1 so as to be revolvable, and a reference numeral 26 is a working device provided on the front side of the upper revolving unit 25 so as to be able to move up and down.

The hydraulic excavator according to the present embodiment has the above-described configuration, and drives the crawler belt 7 with the idler wheel 3 by driving the driving wheel 4 by a traveling motor (not shown) during traveling on the road. A circling operation is performed between the wheel 4 and the vehicle, thereby moving the vehicle forward or backward.

Further, when the crawler belt 7 performs the orbiting operation, the sealing device 21 seals the space between the outer link portion 9 of the track link 8 and the bush 11, so that the bush 11 and the connecting pin 12 In addition, it is possible to prevent foreign matter such as earth and sand from entering the space between them, and to prevent the lubricating oil G filled in the gap between the two from leaking to the outside.

By the way, during the above-mentioned orbiting operation of the crawler belt 7, the track links 8 are provided with arrows F1, F2 shown in FIG.
The thrust load in the direction acts repeatedly. Then, for example, a thrust load in the direction of arrow F1 acts on the track link 8, and as shown in FIG.
When the interval with zero increases, the volume of the accommodation space 24 increases. For this reason, the accommodation space 2 in which the lubricating oil G is accommodated
4 has a negative pressure shape, so that outside air is easily sucked into the accommodation space 24.

On the contrary, when a thrust load, for example, in the direction of arrow F2 acts on the track link 8 and the space between the outer link portion 9 and the bush 11 is reduced as shown in FIG. The volume is reduced. Therefore, the lubricating oil G accommodated in the accommodation space 24 receives a high pressure between the outer link portion 9 and the bush 11 and easily flows out through the contact portions 22B and 22C of the annular seal 22 to the outside.

When the volume of the housing space 24 is repeatedly increased and decreased by the thrust load acting between the track rings 8, the space between the bush 11 and the connecting pin 12 and the space 24 The lubricating oil G contained in each of the insides gradually decreases and disappears, and in this case, a problem such as seizure occurs in the contact portions 22B and 22C of the annular seal 22.

However, in this embodiment, an annular porous member 23 is disposed in the seal mounting hole 9B of the outer link portion 9 so as to surround the annular seal 22 from the outside in the radial direction. The configuration is such that the lubricating oil G is trapped inside 23.

As a result, when the volume of the storage space 24 increases as described above, the lubricating oil G trapped inside the porous member 23 is reduced as shown in FIG. As indicated by the arrow A, replenishment can be performed by suction using a negative pressure, and the lubricating oil G can be stored in the housing space 24 while being supplied to the contact portions 22B and 22C of the annular seal 22.

Further, as shown by an arrow B in FIG. 6, when muddy water, earth and sand from the outside penetrates between the outer link portion 9 and the bush 11, the muddy water and the like enter the housing space 24 side. Can be blocked by the porous member 23 and the lubricating oil G trapped inside, and such muddy water and the like can be prevented from entering the annular seal 22 side. Moreover, the lubricating oil G trapped in the porous member 23
The muddy water can be repelled by the ring seal 2
Muddy water can be further prevented from entering the two sides.

On the other hand, as described above, the volume of the storage space 24 is reduced, and the lubricating oil G in the storage space 24 is
When the lubricating oil G flows out as shown by an arrow C in FIG.
Can be absorbed and captured by the porous member 23, and leakage of the lubricating oil G to the outside from between the outer link portion 9 and the bush 11 can be blocked.

Thus, in the present embodiment, as described in the prior art, the circular seal 22 is used when the crawler belt 7 circulates.
Contact portions 22B and 22C of the outer link portion 9 and the bush 1
1, the lubricating oil G can be guided from the porous member 23 to the contact portions 22B and 22C of the annular seal 22 to maintain the contact portions 22B and 22C in a lubricated state. As a result, the occurrence of seizure or the like on the contact portions 22B and 22C can be suppressed, and the durability, life, and the like of the annular seal 22 can be increased.

Further, the lubricating oil G can always be kept in the housing space 24 in which the annular seal 22 is housed,
The contact portion 22B of the annular seal 22 is
22C can be maintained in a lubricating state for a long time, and the durability and the like of the annular seal 22 can be further increased.
Metal noise generated between the annular seal 22 and the outer link portion 9 and the bush 11 can be reduced.

Since the lubricating oil G can always be stored between the bush 11 and the connecting pin 12, the lubricating oil G allows the bush 11 and the connecting pin 12 to be stored.
Can be maintained in a lubricated state, and the occurrence of seizure or the like between the two can be suppressed.
The relative rotation between the shaft and the bush 11 can be maintained at a circular pressure.

Further, it is possible to prevent the contact portions 22B and 22C of the bush 11, the connecting pin 12 and the annular seal 22 from being damaged by foreign matters such as earth and sand, and it is possible to further improve the durability and life thereof.

Further, since the porous member 23 can prevent muddy water from entering the annular seal 22, corrosion such as rust can be prevented from being generated in the annular seal 22 made of a metal material, and the durability of the annular seal 22 can be reduced. Etc. can be further enhanced.

Furthermore, since the porous member 23 is formed in an annular shape by a porous material of continuous cells in which the porosity is continuously communicated, it is possible to uniformly capture the lubricating oil G inside the porous member 23. Accordingly, the total amount of the lubricating oil G supplied from the porous member 23 to the annular seal 22 can be increased, and the lubricating property of the annular seal 22 can also be improved.

Next, FIG. 8 shows a second embodiment of the present invention. The feature of this embodiment is that the annular seal is constituted by a resin annular seal having an M-shaped cross section. The porous member is disposed radially inside and outside the annular seal. In the present embodiment,
The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the figure, reference numeral 31 denotes a seal device according to the present embodiment, which is provided between the outer link portion 9 of the track link 8 and the bush 11 and provided on the outer peripheral side of the connecting pin 12.
The sealing device 31 includes an annular seal 32, an outer porous member 33, and an inner porous member 34, which will be described later.

Reference numeral 32 denotes a seal mounting hole 9B of the outer link portion 9.
An M-shaped annular seal (hereinafter referred to as an annular seal) as a seal member provided in the
Is formed in a substantially M-shaped cross section by using a high-performance resin such as a polyimide resin or a polyamide resin, or an elastic resin material such as urethane rubber or nitrile rubber.

The annular seal 32 has a first contact portion 32A that contacts the inner end face 9C of the outer link portion 9,
Second contact portion 32 that contacts end surface 11A of bush 11
B and an intermediate connecting portion 32C which is a V-shaped bent portion connecting the contact portions 32A and 32B.

Then, the annular seal 32 is
2C is elastically deformed between the abutting portions 32A and 32B, so that an interference is provided between the inner end surface 9C of the outer link portion 9 and the end surface 11A of the bush 11 to seal between the two. ing.

Reference numeral 33 denotes contact portions 32A, 3 of the annular seal 32.
2B, an annular outer porous member provided radially outward of the intermediate connecting portion 32C between the outer connecting members 32C.
3 is formed as an annular body having a substantially square cross section by using a porous elastic resin material in substantially the same manner as the porous member 23 described in the first embodiment, and has a lubricated inside. Oil G is trapped.

Reference numeral 34 denotes an annular inner porous member provided between the connecting pin 12 and the annular seal 32 and provided radially inward of the annular seal 32. The inner porous member 34 is also porous. The elastic resin material is used to form an annular body having a substantially triangular cross section, and a lubricating oil G is trapped inside the annular body.

Thus, also in the present embodiment configured as described above, the outer link portion 9 to which the annular seal 32 is attached is provided.
The lubricating oil G can be held in the seal mounting hole 9B by the outer porous member 33 and the inner porous member 34,
The situation where the lubricating oil G leaks to the outside can be prevented.

When a left and right thrust load (directions indicated by arrows F1 and F2) acts on the track link 8, the lubricating oil G trapped by the outer porous member 33 and the inner porous member 34 is transferred to the bush 11 by the bush 11. Between the connection pin 12 and
Replenishment can be performed between the inner end surface 9C of the outer link portion 9 and the contact portion 32A of the annular seal 32 and between the end surface 11A of the bush 11 and the contact portion 32B of the annular seal 32, respectively.
Lubricity between them can be maintained well.

Also, muddy water and the like from the outside
When penetrated into the side, the muddy water can be repelled by the lubricating oil G in the outer porous member 33, and the muddy water enters between the inner end face 9 </ b> C of the outer link portion 9 and the contact portion 32 </ b> A of the annular seal 32. The situation can be prevented. Also,
As described above, the space between the end face 11A of the bush 11 and the contact portion 32B of the annular seal 32 can be always filled with the lubricating oil G.
It can be repelled by the lubricating oil G between 1A and the contact portion 32A, and it is possible to prevent muddy water from entering between them.

Next, FIGS. 9 to 11 show a third embodiment of the present invention. The feature of this embodiment is that the seal member is constituted by left and right disc springs and these left and right disc springs are used. The right disc spring has a configuration in which an oil groove through which lubricating oil flows is provided on an inner end surface of the outer link portion and an abutting portion side that abuts on an end surface of the bush. Note that, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the figure, reference numeral 41 denotes a connecting pin 12 located between the outer link 9 of the track link 8 and the bush 11 '.
In the sealing device according to the present embodiment, which is provided on the outer peripheral side of the device, the sealing device 41 includes an annular seal 42 and a porous member 47 described later.

Reference numeral 42 denotes a seal mounting hole 9B of the outer link portion 9.
The annular seal 42 is constituted by left and right disc springs 43 and 44 formed in a conical shape with a metal material such as spring steel. These disc springs 43 and 44 are arranged with their ends on the reduced diameter side into which the connecting pins 12 are inserted butted against each other.

Further, the annular seal 42 has a first contact portion 43A in which the end on the radially expanded side of the disc spring 43 elastically contacts the inner end surface 9C of the outer link portion 9, and the diameter of the disc spring 44 is enlarged. The end on the side is a second contact portion 44A elastically contacting the end surface 11A 'of the bush 11. For this reason, the annular seal 42 supports the thrust load acting between the outer link portion 9 and the bush 11 ′, and gives a tight allowance to the outer link portion 9 and the bush 11 ′,
It is configured to seal between them.

Are positioned on the opposite side to the inner end face 9C of the outer link portion 9 and are in contact with the contact portions 43A of the disc spring 43.
The oil groove 45 is formed as a rectangular cutout groove which is elongated in the radial direction from the end of the disc spring 43 on the diameter-expanding side. I have. The oil groove 45 allows the lubricating oil G to flow radially between the inner end surface 9C of the outer link portion 9 and the contact portion 43A of the disc spring 43, and enhances the lubricity between the two. It has become.

Are end faces 1 of the bush 11 '.
1A ', the contact portion 44A of the disc spring 44
A plurality of other oil grooves provided circumferentially spaced on the side,
The oil groove 46 is also formed substantially in the same manner as the oil groove 45, and allows the lubricating oil G to flow radially between the end surface 11A 'of the bush 11' and the contact portion 44A of the disc spring 44,
It is configured to enhance the lubricity between the two.

Reference numeral 47 denotes an annular porous member provided in the seal mounting hole 9B of the outer link portion 9 together with the annular seal 42 and used in the present embodiment. The porous member 47 is the same as the first embodiment. In substantially the same manner as the porous member 23 described above, the annular member 42 is formed of a porous elastic resin material as an annular body that surrounds the annular seal 42 from the outside in the radial direction. Then, the lubricating oil G is captured inside the porous member 47.

The porous member 47 is connected to the outer link 9
A housing space 48 for housing the annular seal 42 is defined between the inner end surface 9C of the bush 11 and the end surface 11A 'of the bush 11', and the lubricating oil G is sealed in the housing space 48. .

Thus, also in the present embodiment configured as described above, it is possible to obtain substantially the same operation and effect as in the first embodiment. In particular, in the present embodiment, the contact portions 43A, 4A of the disc springs 43, 44 constituting the annular seal 42.
4A are provided with oil grooves 45 and 46, respectively.
And the outer link portion 9 and the bush 11 'can be further enhanced in lubricity, and the lubricity therebetween can be further enhanced.

The annular seal 42 is connected to two disc springs 4
3 and 44, these disc springs 43,
44 and the bush 11 '
And the thrust load acting between them can be stably supported, and rattling of the two in the left and right directions can be further suppressed.

Next, FIGS. 12 to 14 show a fourth embodiment of the present invention.
This embodiment is characterized in that the annular seal as a seal member is provided with a through hole through which lubricating oil flows between the outer link portion and the bush.
Note that, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

Reference numeral 51 denotes an outer link portion 9 of the track link 8.
The seal device according to the present embodiment, which is provided between the bush 11 and the outer periphery of the connecting pin 12, includes an annular seal 52, an outer porous member 53, and an inner porous member (described later). It is constituted by a member 54.

Reference numeral 52 denotes a seal mounting hole 9B of the outer link portion 9.
An M-shaped annular seal (hereinafter, referred to as an annular seal) as a seal member used in the present embodiment provided in the inside, the annular seal 52 is substantially the same as the annular seal 32 described in the second embodiment. In addition, the first contact portion 52A, the second contact portion 52B, and the intermediate connecting portion 52C constitute a resin annular seal having an M-shaped cross section.

Reference numeral 53 denotes contact portions 52A, 5A of the annular seal 52.
2B, an annular outer porous member provided radially outside the intermediate connecting portion 52C between the outer connecting members 52B.
3 is formed similarly to the porous member 33 described in the second embodiment, and the lubricating oil G is trapped inside.

An annular inner porous member 54 is provided between the connecting pin 12 and the annular seal 52 and is provided radially inside the annular seal 52.
Is formed in the same manner as the inner porous member 34 described in the second embodiment, and the lubricating oil G is trapped inside.

Reference numerals 55, 55 denote first through holes which are provided in the first contact portion 52A of the annular seal 52 on the outer peripheral side and penetrate in the axial direction (thickness direction). 55 is
Outer link portion 9 sandwiching contact portion 52A of annular seal 52
The lubricating oil G is allowed to flow between the inner end face 9C side and the outer porous member 53 side.

Reference numerals 56, 56 denote second through holes which are provided in the second contact portion 52B of the annular seal 52 on the outer peripheral side and penetrate in the axial direction (thickness direction). 56 is
The lubricating oil G is disposed between the end surface 11A of the bush 11 and the outer porous member 53 with the contact portion 52B of the annular seal 52 interposed therebetween.
Is allowed to be distributed.

Reference numerals 57 and 57 denote third through holes provided in the intermediate connecting portion 52C of the annular seal 52 so as to radially penetrate the intermediate connecting portion 52C.
C and the outer porous member 53 side and the inner porous member 5
The lubricating oil G is allowed to flow between the lubricating oil G and the fourth side.

Thus, in the present embodiment configured as described above, the lubricating oil G can be freely circulated between the outer porous member 53 and the inner porous member 54 by the third through hole 57. For example, when the lubricating oil G of the outer porous member 53 runs short, the lubricating oil G of the inner porous member 54 can be guided to the outer porous member 53 through the third through hole 57 to compensate for the shortage. The outer porous member 53 and the inner porous member 54 can always uniformly capture the lubricating oil G.

Then, the lubricating oil G trapped in the outer porous member 53 is supplied to the annular seal 52 through the first through hole 55.
Can be smoothly guided between the abutting portion 52A and the inner end surface 9C of the outer link portion 9, and the outer porous member 53
The lubricating oil G trapped in the inside is transferred to the contact portion 52 </ b> B of the annular seal 52 and the end surface 11 of the bush 11 through the second through hole 56.
A can be smoothly guided between the annular seal 52 and the lubricating property and the durability of the annular seal 52 can be further improved.

In the third embodiment, the disc spring 4
The oil grooves 45,
46, the contact portions 43A, 44
A has been described as a configuration that enhances the lubricity of A. Alternatively, for example, as in the modified examples shown in FIGS. A plurality of through holes 61, 62 are provided, respectively, and the disc springs 43 ', 4
4 'may be configured to enhance lubricity.

In each of the embodiments, the porous member is formed by a single member. Alternatively, for example, a plurality of sponge pieces may be formed between the outer link portion and the bush. The sponge pieces may be arranged together in a direction, and an annular porous member may be constituted by these sponge pieces.

In the fourth embodiment, a first through hole 55, a second through hole 56, and a third through hole 57 are provided in the annular seal 52, and the annular seal 52 is formed by these through holes 55, 56, 57. Although the configuration has been described as enhancing the lubricity of the contact portions 52A and 52B of FIG.
As in the modification shown in FIG. 18, a plurality of oil grooves 71, 72 substantially the same as in the third embodiment may be provided in the contact portions 52A ', 52B' of the annular seal 52 '.

Further, in each of the embodiments, a hydraulic shovel has been described as an example of a tracked vehicle, but the present invention is not limited to this and can be widely applied to a tracked vehicle such as a hydraulic crane. is there.

[0093]

As described above in detail, according to the first aspect of the present invention, an annular seal member made of an elastic material is disposed between the inner end face of the outer link portion of the track link and the end face of the bush with a tight allowance. An annular porous member made of a porous elastic material capable of catching lubricating oil is provided between the outer link portion and the bush together with the seal member,
Since the seal device is constituted by the seal member and the porous member, the porous member can continue to hold the lubricating oil in the space between the outer link portion of the track link and the bush. Leakage to the outside can be prevented, and the lubricating oil can always keep the seal member in a lubricated state. Further, the porous member can also prevent earth and sand, muddy water and the like from entering from entering the seal member.

Thus, abrasion, damage, seizure, and the like can be prevented from occurring between the seal member and the inner end surface of the outer link portion, and between the seal member and the end surface of the bush, and the durability and life of the seal member can be prevented. And reliability can be improved.

Further, according to the second aspect of the present invention, the porous member is formed as an annular body, and the seal member is surrounded from the outside in the radial direction by the porous member, so that the space between the outer link portion and the bush is formed. Since the lubricating oil is sealed, the porous member can prevent the lubricating oil supplied to the seal member from leaking to the outside, or can prevent muddy water or the like from entering from entering the seal member, The lubricity of the seal member can be enhanced, and the durability, life, and the like can be further extended.

Further, according to the invention of claim 3, the porous member is
Since the porous material is formed of a continuous open-celled porous material, the lubricating oil can be uniformly trapped in the entire interior of the porous member, and is supplied to the annular seal from the porous member. The total amount of lubricating oil can be increased, which can also improve the lubricity of the annular seal.

Further, according to a fourth aspect of the present invention, the seal member is formed as an annular seal having a V-shaped bent portion at the axial middle portion, and both ends of the annular seal in the axial direction are formed inside the outer link portion. Since the end surface and the end surface of the bush are configured to be brought into contact with each other, lubricating oil captured by the porous member can be supplied to these contact surfaces, and the contact surfaces can be maintained in a lubricated state. As in the invention, the durability and life of the annular seal can be extended. Also, for example, at the time of the orbital movement of the crawler belt, for example, the left,
Even when a thrust load in the right direction is applied, rattling between the track links in the left and right directions can be prevented by the annular seal, and running stability can be improved.

Further, as in the invention of claim 5, the seal member is constituted by an annular seal made of resin having an M-shaped cross section, and the porous member is formed on the inside and outside in the radial direction of the annular seal. Even in the case of the arrangement, the lubricating oil can be kept around the annular seal by the porous member, and the durability and life of the annular seal can be improved by the lubricating oil.

On the other hand, even when the sealing member is constituted by a plurality of disc springs arranged in abutting relationship with each other between the inner end face of the outer link portion and the end face of the bush as in the invention of claim 6, Can keep lubricating the disc spring,
The durability and life of the disc spring can be improved. Also,
The thrust load acting between the outer link portion and the bush can be stably supported by each of these disc springs, and traveling stability can be further enhanced.

According to a seventh aspect of the present invention, the seal member has at least one of a first contact portion that contacts the inner end surface of the outer link portion and a second contact portion that contacts the end surface of the bush. Since the oil groove through which the lubricating oil flows is provided in any one of the contact portions, the oil groove is provided between the first contact portion of the seal member and the outer link portion, or the second contact portion of the seal member. The lubricating oil can be smoothly guided between the bush and the oil groove, so that the occurrence of seizure or the like in the seal member can be further suppressed, and the durability and life of the seal member can be further improved.

Further, according to the invention of claim 8, the lubricating oil is circulated through the through hole provided in the seal member in the space between the outer link portion and the bush. The lubricating oil can be guided substantially uniformly by the through holes, and the durability and the like of the seal member can be enhanced almost in the same manner as the seventh aspect of the present invention.

[Brief description of the drawings]

FIG. 1 is an external view showing a hydraulic excavator applied to a first embodiment of the present invention.

FIG. 2 is an enlarged front view showing a main part of the crawler belt in FIG.

FIG. 3 is a partially broken plan view showing a connecting portion between the track links, as viewed from the direction of arrows III-III in FIG. 2;

FIG. 4 is an enlarged cross-sectional view showing a connecting portion between the track links as viewed from the direction of arrows IV-IV in FIG.

FIG. 5 is an enlarged sectional view showing a main part of the sealing device in FIG. 4 in an enlarged manner.

FIG. 6 is a cross-sectional view showing a state where an interval between an outer link portion and an inner link portion is enlarged, as viewed from a position similar to FIG. 5;

FIG. 7 is a cross-sectional view showing a state where a distance between an outer link portion and an inner link portion is reduced, as viewed from the same position as in FIG. 5;

FIG. 8 is an enlarged cross-sectional view of a main part showing a sealing device according to a second embodiment of the present invention in an enlarged manner.

FIG. 9 is an enlarged cross-sectional view of a main part showing a sealing device according to a third embodiment of the present invention in an enlarged manner.

FIG. 10 is a sectional view showing the annular seal in FIG. 9 alone;

11 is a plan view of the annular seal as viewed from the direction indicated by arrows XI-XI in FIG. 10;

FIG. 12 is an enlarged sectional view of a main part showing a sealing device according to a fourth embodiment of the present invention in an enlarged manner.

FIG. 13 is a sectional view showing the annular seal in FIG. 12 alone;

FIG. 14 is a plan view of the annular seal as viewed from the direction indicated by arrows XIV-XIV in FIG. 13;

FIG. 15 is a sectional view showing an annular seal alone according to a modification of the third embodiment of the present invention.

FIG. 16 is a plan view of the annular seal as viewed from the direction indicated by arrows XVI-XVI in FIG. 15;

FIG. 17 is a sectional view showing an annular seal alone according to a modification of the fourth embodiment of the present invention.

18 is a plan view of the annular seal as viewed from the direction indicated by arrows XVIII-XVIII in FIG. 17;

[Explanation of symbols]

Reference Signs List 7 Crawler track 8 Track link 9 Outer link part 9C Inner end face 10 Inner link part 11, 11 'Bush 11A, 11A' End face 12 Connecting pin 21, 31, 41, 51 Sealing device 22, 32, 42, 52, 52 'Annular seal (Seal member) 22A Bent portion 22B, 22C, 32A, 32B, 43A, 44A, 5
2A, 52B, 52A ', 52B' Contact part 23, 47 Porous member 24, 48 Housing space 33, 53 Outer porous member 34, 54 Inner porous member 43, 43 ', 44, 44' Disc spring 45, 46, 71, 72 Oil groove 55 First through hole 56 Second through hole 57 Third through hole 61, 62 Through hole

Claims (8)

[Claims] 1. A left and right track link having an outer link portion formed on one side in the longitudinal direction and an inner link portion on the other side in the longitudinal direction and connected endlessly to each other, and an inner side of each of the track links. A bush provided between the link portions and having both left and right ends facing the outer link portion; and a bush inserted into the bush and provided with the left and right ends fitted to the outer link portion. A crawler belt comprising: a connecting pin that is joined and connected; and a sealing device that is located between an outer link portion of each of the track links and a bush and is provided on an outer peripheral side of the connecting pin. A seal member formed in a ring shape from a material and disposed between the inner end surface of the outer link portion and the end surface of the bush with a tight allowance, and a porous elastic material for trapping lubricating oil therein. Track, characterized by being configured by a porous member which is elastically deformable disposed between the annularly formed the outer link portion and the bush. 2. The structure according to claim 1, wherein the porous member is formed as an annular body surrounding the seal member from the outside in the radial direction, and seals the lubricating oil in a space between the outer link portion and the bush. Item 2. The crawler according to item 1. 3. The crawler belt according to claim 1, wherein the porous member is formed of a porous material of open cells in which the porous body communicates continuously. 4. The seal member is constituted by an annular seal having both ends in the axial direction abutting on the inner end surface of the outer link portion and the end surface of the bush, and a middle portion in the axial direction having a V-shaped bent portion. The crawler according to claim 1, 2, or 3. 5. The seal member comprises a resin-made annular seal having a M-shaped cross section, and the porous member is located between the outer link portion and a bush in a radial direction of the annular seal. Claim 1, which is arranged inside and outside of
Crawler track according to 2 or 3. 6. The seal member according to claim 1, wherein said seal member is constituted by a plurality of disc springs arranged in a state of abutting each other between an inner end surface of said outer link portion and an end surface of a bush. Crawler track as described. 7. The seal member includes a first contact portion that contacts an inner end surface of the outer link portion, and a second contact portion that contacts an end surface of the bush. 4. An oil groove through which the lubricating oil flows is provided in at least one of the second contact portions.
Crawler track according to 4, 5, or 6. 8. The seal member is provided with a through hole through which the lubricating oil flows in a space between the outer link portion and the bush. Tracks described in.