JP2001080550A - Guide roller device for crawler vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent gall, seizure and the like from being generated between a roller and a thrust plate. SOLUTION: A roller 33 of an upper side roller device 31 is integrally formed of an outside large-diametric cylindrical part 34 and an inside small-diametric cylindrical part 35 using a metal material having self-lubricity such as cast iron. A flangeless bush 36 is formed into a cylindrical body. A thrust plate 38 is directly brought into slide-contact with an end face 35C of the small- diametric cylindrical part 35, and a lubricating oil from an oil reservoir 40 is introduced into a plate storing chamber 37 through a radial-directional oil pasage 39D between the thrust plate 38 and a lid body 39, so as to lubricate the plate 38. An axial-directional oil passage 41 is provided inside the cylindrical part 35 to communicate a space between the plate storing chamber 37 and a seal storing chamber 22 to lubricate also a floating seal 23 thereby.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guide roller device for a tracked vehicle suitably used for a tracked vehicle such as a hydraulic shovel or a hydraulic crane.

[0002]

2. Description of the Related Art In general, a tracked vehicle such as a hydraulic shovel or a hydraulic crane travels on an unleveled road surface, so that a drive wheel provided at one end of a side frame constituting a track frame and a drive wheel provided at the other end are provided. The crawler belt is wound between the idler wheels provided in the vehicle. The side frame is usually provided with a guide roller device for guiding the crawler belt between the driving wheels and the idler wheels (for example, Japanese Patent Application Laid-Open No. 8-282554).

With reference to FIGS. 5 to 7, an example in which this type of conventional guide roller device for a tracked vehicle is applied to a lower traveling body of a hydraulic shovel will be described.

In the drawings, reference numeral 1 denotes a lower traveling body of a hydraulic shovel, 2 denotes a track frame of the lower traveling body 1, and the track frame 2 includes a center frame 3 and a circle provided at the center of the center frame 3. It is generally constituted by a body 4 and a pair of side frames 5 (only one is shown) which are located on the left and right sides of the center frame 3 and extend forward and backward.

Reference numeral 6 denotes a driving wheel provided at one end of the side frame 5. The driving wheel 6 is rotated by a traveling motor (not shown) or the like to make a crawler belt 8 described later revolve. is there. Reference numeral 7 denotes an idler wheel provided on the other end side of the side frame 5. The idler wheel 7 is attached in a direction away from the drive wheel 6 by a crawler belt tensioning device (not shown) provided in the side frame 5. And the crawler belt 8 is given an appropriate tension.

Reference numeral 8 denotes a crawler belt wound between the driving wheel 6 and the idler wheel 7. The crawler belt 8 is guided by a lower roller device 9 and an upper roller device 11 and is driven by a traveling motor. The lower traveling body 1 travels around between the driving wheel 6 and the idler wheel 7.

Reference numerals 9, 9,... Denote a plurality of lower roller devices rotatably provided on the lower surface side of the side frame 5. The lower roller device 9 is located between the side frame 5 and the crawler belt 8. It guides the crawler belt 8 that moves around.

Reference numerals 11 and 11 denote two upper roller devices rotatably provided on the upper surface side of the side frame 5, and the upper roller device 11 guides the orbiting crawler belt 8 while supporting it from below. It is. The upper roller device 11 is connected to the side frame 5 via the mounting bracket 12.
, A support shaft 14, a roller 15, a flanged bush 18, a thrust plate 20, a floating seal 23 and a lid 24, which will be described later.

Here, the mounting bracket 12 is attached to a base 13 welded to the upper surface of the side frame 5 by bolts 13.
A, a flat attachment portion 12A fastened via 13A or the like
And a cylindrical portion 12B provided on the mounting portion 12A and projecting leftward and rightward of the side frame 5, and an inner peripheral side of the cylindrical portion 12B is fitted with a support shaft 14. It has a hole 12C. The cylindrical portion 12B
On the protruding end side, a seal mounting hole 12D having a diameter larger than that of the shaft insertion hole 12C is provided.

Reference numeral 14 denotes a support shaft fixed to the side frame 5 via a mounting bracket 12.
Reference numeral 4 denotes a mounting bracket 12 on one end side (base end side) in the axial direction.
The other end side (tip side) is a free end and extends in the axial direction.

Reference numeral 15 denotes a roller as a rolling element rotatably supported on the distal end side of the support shaft 14.
As shown in FIG. 7, for example, a steel material such as carbon steel (S45C) is subjected to machining such as cutting to form a stepped cylinder as a whole. And the roller 15
The large-diameter cylindrical portion 16 formed with abutment surfaces 16A, 16A on the outer peripheral side to which the crawler belt 8 abuts in the axial direction, and the large-diameter cylindrical portion 16 are integrally formed on the inner peripheral side in the middle in the axial direction. And a small-diameter cylindrical portion 17 having a bush fitting hole 17A formed on the inner peripheral side thereof. The small-diameter cylindrical portion 17 has end faces 17B and 17C at one end and the other end in the axial direction, respectively. .

The large-diameter cylindrical portion 16 of the roller 15 has a seal mounting hole 16B which is located on one inner side in the axial direction of the roller 15 and in which a floating seal 23 to be described later is mounted. And a bracket housing hole 16C that is open to the outside and that houses the protruding end side of the cylindrical portion 12B of the mounting bracket 12. The inner periphery on the other side in the axial direction of the large-diameter cylindrical portion 16 is a lid mounting hole 16D.

Reference numeral 18 denotes a bush fitting hole 17A for the roller 15.
The flanged bush 18 is a cylindrical bush with a flange provided by being fitted on the roller 1 as shown in FIG.
5 is press-fitted into the bush fitting hole 17A, and the support shaft 14 is slidably inserted on the inner peripheral side.
A flange portion 18B that is bent radially outward from the end portion A and abuts against the end surface 17C of the roller 15.

The collar 1 of the flanged bush 18
8B is configured to be in sliding contact with the thrust plate 20 and receive a thrust load acting on the roller 15 between the thrust plate 20 and the thrust plate 20.

Reference numeral 19 denotes a large-diameter cylindrical portion 16 constituting the roller 15.
The plate accommodating chamber 19 is provided in the inner portion of the lid mounting hole 16D.
A thrust plate 20 to be described later is housed together with the flange portion 18B of the flanged bush 18 inside the lid body mounting hole 16D so as to be located between 7C and the distal end surface of the cylindrical portion 24B of the lid body 24. I have. And this plate accommodation room 19
Is connected to an oil reservoir 25 described later, and lubricating oil from the oil reservoir 25 is guided into the plate storage chamber 19.

20 is accommodated in the plate accommodation chamber 19,
A thrust plate fixedly provided on the other end side (front end side) of the support shaft 14 by fixing bolts 21 and 21. The thrust plate 20 is formed by a flange portion 18B of a flanged bush 18.
The roller 1 is brought into sliding contact with the flange 18B.
The thrust load acting on the support shaft 5 is received, and the roller 15 is prevented from coming off the support shaft 14.

Reference numeral 22 denotes a seal housing chamber provided between the support shaft 14 and the inner periphery of the large-diameter cylindrical portion 16 of the roller 15 on one side in the axial direction.
Seal mounting hole 12D of roller 15 and seal mounting hole 16 of roller 15
B, and a floating seal 23 is accommodated therein.

Reference numeral 23 denotes a floating seal which is provided in the seal housing chamber 22 and serves as a seal member for sealing one side in the axial direction of the roller 15 in a liquid-tight manner. The floating seal 23 is composed of a pair of seal rings 23A, 23A. 23A
And the seal rings 23A, 23A and the mounting bracket 1.
2 seal mounting hole 12D, roller 15 seal mounting hole 1
6B and a pair of O-rings 23 respectively sandwiched between
B, 23B.

The floating seal 23 is
The seal oil 23A is sealed between the support shaft 14 and the roller 15 by the respective seal rings 23A slidingly contacting the seal mounting holes 12D and 16B with the interference by the ring 23B.

Reference numeral 24 denotes the other axial side of the roller 15 (tip side).
And a lid for covering an oil reservoir 25 formed on the other side of the roller 15, which will be described later. The lid 24 has a lid 24 </ b> A having a diameter larger than the lid mounting hole 16 </ b> D of the roller 15. And a cylindrical portion 24B whose base end is integrally formed with the lid portion 24A and fitted into the lid body mounting hole 16D in a press-fit state. Lubricating oil is supplied between the support shaft 14 and the roller 15 together with the floating seal 23. It is configured to be sealed.

Here, radial oil passages 24C, 24C are provided between the thrust plate 20 and the distal end surface of the cylindrical portion 24B of the lid 24, and the radial oil passages 24C are provided.
The lubricating oil in the oil reservoir 25 described below is supplied to the plate storage chamber 19.
It leads to inside.

Reference numeral 25 denotes an oil reservoir formed between the thrust plate 20 and the lid 24 and formed on the other side of the roller 15. The oil reservoir 25 is provided with a bush 18 having a flange and a floating seal 23. It stores lubricating oil for lubricating or cooling the sliding contact portion of the seal ring 23A.

Reference numerals 26, 26 denote a plurality of axial oil passages provided through the small-diameter cylindrical portion 17 of the roller 15 in the axial direction. The axial oil passages 26 extend from the oil reservoir 25 to the respective radial oil passages. 2
A part of the lubricating oil supplied into the plate housing chamber 19 via 4C is guided into the seal housing chamber 22.

In the upper roller device 11 according to the prior art constructed as described above, when the crawler belt 8 rotates between the drive wheel 6 and the idler wheel 7, the roller 15 rotates with respect to the support shaft 14 while the crawler belt 8 rotates. Is supported from below, and the crawler belt 8 is guided by the upper roller device 11 so as to maintain an appropriate endless track.

At this time, the lubricating oil in the oil reservoir 25 is supplied to the plate housing 19 via the radial oil passage 24C.
Guided inside, flanged bush 18, thrust plate 2
0, and a part of the lubricating oil in the plate housing chamber 19 passes through the seal housing chamber 2 through the axial oil passage 26.
2 to lubricate the sliding contact portion of each seal ring 23A constituting the floating seal 23.

As described above, during the orbiting operation of the crawler belt 8, lubrication of the flanged bush 18, the seal ring 23A of the floating seal 23, and the like is performed, so that the smooth rotation of the roller 15 with respect to the support shaft 14 is maintained. In this way, a stable circling operation of the crawler belt 8 can be obtained.

[0027]

In the upper roller device 11 according to the prior art described above, the flanged bush 18 has a flange 18B formed by bending the end of the cylindrical portion 18A radially outward. The thrust load acting on the roller 15 is received between the flange 18B and the thrust plate 20.

For this reason, the flange portion 18 of the flanged bush 18
When the thrust load is applied to B, the stress due to the thrust load concentrates on the bent portion between the cylindrical portion 18A and the flange portion 18B, and there is a possibility that a crack may be formed in the bent portion. There is.

Also, a flange portion 18B of the flanged bush 18
Is formed by bending the cylindrical portion 18A, so that the cylindrical portion 18A is formed as described above even when the flange portion 18B is processed.
There is a problem that a crack may be formed in a bent portion between A and the flange portion 18B. Further, there is a problem that the overall shape of the flanged bush 18 is complicated by the flange portion 18B, and the workability at the time of manufacturing is reduced.

On the other hand, as another conventional technique, a flange portion is eliminated from a bush with a flange, and lubricating bearing plates made of brass or the like are integrally provided on both sides of a thrust plate to act on rollers. There is also known a configuration in which a thrust load is received between a roller and a bearing plate, and between a lid and a bearing plate (for example, Japanese Utility Model Laid-Open No.
No. 8-121776).

However, in the case of this prior art, since it is necessary to provide a special bearing plate made of brass or the like on the thrust plate, there is a problem that the overall manufacturing cost is high.

In this prior art, a groove is formed on the outer peripheral side of the support shaft to guide the lubricating oil from the oil reservoir provided between the lid and the thrust plate to the floating seal. Since the spiral oil passage is formed, there is also a problem that the material strength of the support shaft itself is reduced.

The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to improve the workability and durability of a bush, and at the same time, to seize between a roller and a thrust plate. It is an object of the present invention to provide a guide roller device for a tracked vehicle in which seizure or the like can be prevented from occurring and the material strength of a support shaft can be increased.

[0034]

In order to solve the above-mentioned problems, a guide roller device for a tracked vehicle according to the present invention is provided.
A support shaft, one end of which is fixed to the track frame of the tracked vehicle and the other end of which is a free end, extending in the axial direction; and a bush fitted on the inner peripheral side rotatably supported by the support shaft for guiding the crawler belt. A rolling element provided with a mounting hole, a bush provided to be fitted in a bush fitting hole of the rolling element, the support shaft being slidably inserted on the inner peripheral side, and the other end of the support shaft A thrust plate fixedly provided on the side of the rolling element and receiving a thrust load acting on the rolling element; and a seal receiving chamber provided between the support shaft and one end of the rolling element, and an axial direction of the rolling element. A sealing member that seals one side in a liquid-tight manner, and a lid that is provided on the other axial side of the rolling element and covers an oil reservoir formed on the other axial side of the rolling element. I have.

A feature of the structure adopted by the first aspect of the present invention is that the rolling element includes a large-diameter cylindrical portion having an abutting surface with which the crawler belt comes into contact with an outer peripheral side for guiding the crawler belt. A small-diameter cylindrical portion integrally formed on the inner peripheral side of the axially intermediate portion of the cylindrical portion and having the bush fitting hole formed on the inner peripheral side, and integrally molded using a lubricating metal material; An axial oil passage extending axially through the inside of the small-diameter cylindrical portion and communicating between the oil sump chamber and the seal accommodating chamber; the bush is formed as a flangeless cylindrical body; The plate is configured to be in contact with the end surface of the small-diameter cylindrical portion.

With this configuration, during the orbiting operation of the crawler belt, the lubricating oil in the oil reservoir formed on the other side of the rolling element lubricates the contact surface between the thrust plate and the small-diameter cylindrical portion of the rolling element. Can be kept in a state. In addition, since the rolling element is molded integrally with the small-diameter cylindrical portion and the large-diameter cylindrical portion using a lubricating metal material, the lubrication between the contact surfaces between the thrust plate and the small-diameter cylindrical portion is further improved. It is possible to prevent the occurrence of seizure, galling and the like between the contact surfaces.

Further, a part of the lubricating oil in the oil reservoir is guided to the seal accommodating chamber through an axial oil passage provided in the small-diameter cylindrical portion of the rolling element, thereby keeping the seal member in a lubricated state. it can. Furthermore, since the bush is formed as a cylindrical body without a flange, the bush does not require the processing of the flange as described in the related art, and the bush can be easily processed.

Further, the invention of claim 2 is configured such that the axial oil passage is located on the outer diameter side of the thrust plate and is opened at the end face of the small diameter cylindrical portion. Thereby, the lubricating oil in the oil reservoir can be smoothly guided from the outer diameter side of the thrust plate to the axial oil passage.

Further, according to a third aspect of the present invention, the lid is brought into contact with the thrust plate in a state where the lid is pressed into the inner circumference on the other side in the axial direction of the large-diameter cylindrical portion, and between the contact surface between the thrust plate and the lid. Has a configuration in which a radial oil passage communicating the oil reservoir with the axial oil passage is provided.

Thus, the thrust load acting on the rolling element is received both between the contact surface between the small-diameter cylindrical portion of the rolling element and the thrust plate and between the contact surface between the thrust plate and the lid. Can be. Further, the lubricating oil in the oil reservoir can be guided into the plate housing chamber through the radial oil passage and the axial oil passage.

Further, when the lubricating metal material used for the rolling element is made of cast iron, the cast iron has self-lubricating properties, so that the end face of the small-diameter cylindrical portion of the rolling element, the thrust plate, The lubricating property can be further improved.

[0042]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a guide roller device for a tracked vehicle according to an embodiment of the present invention is applied to a hydraulic shovel will be described below with reference to FIGS.
In the present embodiment, the same components as those of the above-described related art are denoted by the same reference numerals, and description thereof will be omitted.

In the drawing, reference numeral 31 denotes an upper roller device according to the present embodiment. The upper roller device 31 is substantially the same as the upper roller device 11 described in the related art, and includes a floating seal 23, a support shaft 32 described later, The roller 33, the collarless bush 36, the thrust plate 38, and the lid 39 are substantially constituted.

Reference numeral 32 denotes a support shaft used in the present embodiment. The support shaft 32 is formed substantially in the same manner as the support shaft 14 described in the related art, and one end in the axial direction is the mounting bracket 12.
To the side frame 5.

Reference numeral 33 denotes a roller as a rolling element rotatably supported on a support shaft 32 via a collarless bush 36. The roller 33 is substantially the same as the roller 15 described in the first embodiment. , A large-diameter cylindrical portion 34, and a small-diameter cylindrical portion 35 integrally formed on the inner peripheral side of the large-diameter cylindrical portion 34 in the axial middle thereof. The large-diameter cylindrical portion 34 is provided with contact surfaces 34A, 34A, a seal mounting hole 34B, a bracket housing hole 34C, and a lid mounting hole 34D.
The small-diameter cylindrical portion 35 is provided with a bush fitting hole 35A and end faces 35B and 35C.

Here, the roller 33 is such that the large-diameter cylindrical portion 34 and the small-diameter cylindrical portion 35 are integrally formed by casting using a lubricating metal material made of graphite cast iron (for example, FCD, FCV or the like). Therefore, the entire structure is different from that of the related art formed by machining such as cutting using a steel material. The graphite cast iron used as the material of the roller 33 contains countless graphite particles inside, and has high self-lubricating properties due to the graphite particles.

36 is a bush fitting hole 35A of the roller 33
The collarless bush 36 used in the present embodiment is provided by being fitted to the bushing. The collarless bush 36 is made of, for example, a metal material having slidability, abrasion resistance, and the like. Although formed almost similarly to the bush 18,
In this bush 36, the flange 18B according to the prior art is eliminated. For this reason, the collarless bush 36 is formed as a cylindrical body having a substantially constant wall thickness over the entire length in the axial direction.

Reference numeral 37 denotes a large-diameter cylindrical portion 34 constituting the roller 33.
The plate accommodating chamber used in the present embodiment is provided in the lid mounting hole 34D of the present embodiment. The plate accommodating chamber 37 has an end surface 35C of the small-diameter cylindrical portion 35 and a contact surface 39C of the lid 39 described later.
And is formed in the cover mounting hole 34D and accommodates a thrust plate 38 described later therein.

The plate storage chamber 37 communicates with an oil storage chamber 40 described later, and lubricating oil from the oil storage chamber 40 is guided to the plate storage chamber 37. In the plate accommodating chamber 37, an annular space 37A is formed between the outer diameter end of the thrust plate 38 and the space 37A. The space 37A is provided with a radial oil passage 39D of the lid 39 and an axial oil passage 4 described later.
1 to form a communication path communicating with each other.

38 is accommodated in the plate accommodation chamber 37,
The thrust plate 38 is fixedly provided on the tip end side of the support shaft 32. The thrust plate 38 is formed substantially in the same manner as the thrust plate 20 described in the related art.
3 is retained with respect to the support shaft 32.

However, the thrust plate 38 comes into sliding contact with an end face 35C provided on the small-diameter cylindrical portion 35 of the roller 33, and receives a thrust load acting on the roller 33 between the end face 35C. ing. Further, the outer diameter of the thrust plate 38 is formed smaller than the inner diameter of the plate storage chamber 37 by a certain dimension, thereby forming the space 37A in the plate storage chamber 37 as described above.

Reference numeral 39 denotes a lid used in the present embodiment, which is fitted in the lid mounting hole 34D of the roller 33. The lid 39 is made of graphite cast iron (for example, F
It is formed using a self-lubricating metal material such as CD, FCV, or the like. As shown in FIG. 3, the lid 39 is substantially the same as the lid 24 described in the related art,
9A and a cylindrical portion 3 whose base end is integrally formed with the lid 39A.
9B, and the cylindrical portion 39B is press-fitted and attached to the cover attaching hole 34D of the roller 33.

The lid 39 has an abutting surface 39C at which the distal end surface of the cylindrical portion 39B abuts (slids) on the thrust plate 38.
And the thrust load acting on the roller 33 is
It is configured to receive between the 9C and the thrust plate 38.

Here, for example, four radial oil passages 39D are provided on the contact surface 39C of the lid 39 between the thrust plate 38 as shown in FIG. The passage 39D is formed by forming a groove in the contact surface 39C of the cover 39 in the radial direction. The radial oil passage 39 </ b> D is configured to allow the oil reservoir 40 to communicate with an axial oil passage 41 described later through the plate housing chamber 37.

Reference numeral 40 denotes an oil sump chamber for use in the present embodiment, which is located between the thrust plate 38 and the lid 39 and is formed on the other axial side of the roller 33. Oil is stored, and this lubricating oil allows the collarless bush 36,
It lubricates or cools the sliding contact portion of each seal ring 23A of the floating seal 23, the thrust plate 38, and the like.

A plurality of axial oil passages 41, 41 are provided in the small-diameter cylindrical portion 35 of the roller 33 and communicate between the seal accommodating chamber 22 and the plate accommodating chamber 37 in the axial direction. Is formed, for example, by drilling a small-diameter cylindrical portion 35 of the roller 33. Further, the oil passage 42 may be formed integrally when the roller 33 is cast.

The axial oil passage 42 extends through the inside of the small-diameter cylindrical portion 35 in the axial direction, and both ends are opened to end surfaces 35B and 35C, respectively. Here, each of the axial oil passages 41 is located on the outer diameter side of the thrust plate 38 and opens to the end face 35C, and the plate accommodation chamber 3
7 communicates with the space 37A.

The upper roller device 31 according to the present embodiment has the above-described configuration, and its basic operation is not significantly different from that of the prior art.

However, in the present embodiment, the rollers 33
The large-diameter cylindrical portion 34 and the small-diameter cylindrical portion 35 are integrally molded using a self-lubricating metal material such as cast iron, and by using a flange-less bush 36, the roller 33 The roller 33 is in direct sliding contact with an end surface 35C provided on the small-diameter cylindrical portion 35 of the roller 33. Then, in the plate accommodating chamber 37 for accommodating the thrust plate 38,
The lubricating oil from the oil reservoir 40 is supplied through the radial oil passage 39D.

Therefore, the lubricating oil supplied into the plate accommodating chamber 37 can always provide a good lubrication between the end face 35 C of the roller 33 and the thrust plate 38, and the end face 35 C of the roller 33 can be made of graphite cast iron used for the roller 33.
And thrust plate 38 can be further enhanced in lubricity (conformability), eliminating the cause of seizure, galling, etc., between the two and the thrust plate 38 life,
Durability and the like can be improved.

As described in the other related art, it is not necessary to provide the thrust plate 38 with an expensive metal material such as a bearing plate, so that the manufacturing cost of the entire thrust plate 38 can be reduced.

Since the axial oil passage 41 is configured to open to the end surface 35C of the roller 33 with which the thrust plate 38 slides, the lubricating oil in the axial oil passage 41 causes the end surface 35C of the roller 33 and the thrust plate 38 to contact each other. The lubricating property can be further improved during the heating.

Thus, in the present embodiment, the processing of the flange portion 18B according to the prior art can be omitted when the collarless bush 36 is processed, and cracks and the like occur during the orbiting operation of the crawler belt 8, the processing of the bush 36, and the like. The cause can be eliminated. And the collarless bush 36 can simplify the whole shape, and can improve workability | operativity at the time of manufacture of this bush 36, and so on.

Further, since the axial oil passage 41 communicating between the seal accommodating chamber 22 and the plate accommodating chamber 37 is provided in the roller 33, the outer peripheral side of the support shaft 32 is different from the other prior art described above. Therefore, it is not necessary to form a groove for an oil passage on the support shaft 32, so that the material strength of the support shaft 32 can be maintained high and the number of processing steps of the support shaft 32 can be reduced.

Since the cover 39 has a structure in which the contact surface 39C is brought into contact with the thrust plate 38, the roller 33
Can be received both between the small-diameter cylindrical portion 35 and the thrust plate 38 and between the thrust plate 38 and the lid 39, and when the crawler belt 8 circulates, the roller 33 is connected to the support shaft 32. It can rotate stably to the center.

Further, since a radial oil passage 39D is provided between the thrust plate 38 and the abutment surface 39C of the lid 39, the thrust plate 38 and the lid are formed by the lubricating oil flowing through the radial oil passage 39D. Abutment surface 39 of body 39
C can be lubricated well.

Further, the outer diameter of the thrust plate 38 is formed to be smaller than the inner diameter of the plate accommodating chamber 37 by a certain dimension, and the axial oil passage 41 is formed in the thrust plate 3.
8, an opening is formed in the end face 35C of the small-diameter cylindrical portion 35 at the position on the outer diameter side, so that an annular space 37A can be formed in the plate accommodating chamber 37 between the thrust plate 38 and the plate accommodating chamber. The lubricating oil in 37
A can be smoothly guided from A to the axial oil passage 41 to be supplied into the seal accommodating chamber 22, and the floating seal 23 can be lubricated well.

In the embodiment, the radial oil passage 39
D illustrates the case where it is formed in the lid 39. Alternatively, for example, radial oil passages 38A, 38A,... May be formed in the thrust plate 38 as in a modification shown in FIG.

Further, in the embodiment, the case where the roller 33 is integrally formed by using a lubricating metal material such as cast iron is exemplified. However, the roller may be replaced with a lubricating metal material such as a copper alloy. Or a metal material mixed with a solid lubricant such as graphite.

Further, in the embodiment, the case where the present invention is applied to the upper roller device 31 disposed on the lower traveling body of the hydraulic shovel has been described as an example, but the present invention is not limited to this.
The present invention can be applied to a lower roller device or the like. On the other hand, the present invention is not limited to a hydraulic excavator, and can also be applied to a track-mounted hydraulic crane, an agricultural machine, or the like.

[0071]

As described above in detail, according to the first aspect of the present invention, the rolling element is formed by integrally molding a large-diameter cylindrical portion and a small-diameter cylindrical portion using a lubricating metal material. The small-diameter cylindrical portion is provided with an axial oil passage communicating between the plate accommodating chamber and the seal accommodating chamber, the bush is formed as a flangeless cylindrical body, and the thrust plate is brought into contact with the end surface of the small-diameter cylindrical portion With this configuration, the lubricating oil in the oil reservoir can provide good lubrication between the end face of the small-diameter cylinder and the thrust plate. Can be further enhanced, seizure, galling and the like can be prevented from occurring between the two, and the life and durability of the thrust plate can be increased.

As a result, when forming the bush, as described in the related art, the bending process for forming the flange can be omitted, and the metal fatigue such as cracks can be reduced during the orbiting operation of the crawler belt or the bush. The cause can be eliminated. And the whole shape of a bush can be simplified and workability | operativity at the time of manufacture of a bush can be improved. In addition, since the axial oil passage is provided in the rolling element, it is not necessary to form a groove for the oil passage on the outer peripheral side of the support shaft as described in other related arts, and the material strength of the support shaft is maintained high. In addition to the above, it is possible to reduce the number of processing steps of the support shaft.

According to the second aspect of the present invention, the axial oil passage is located on the outer diameter side of the thrust plate and is opened at the end face of the small-diameter cylindrical portion. It is possible to smoothly guide the seal member to the passage, increase the supply amount of the lubricating oil into the seal accommodating chamber, and satisfactorily lubricate the seal member.

According to the third aspect of the present invention, the lid abuts against the thrust plate while being pressed into the large-diameter cylindrical portion of the rolling element, and an oil sump is provided between the contact surfaces of the thrust plate and the lid. Since the chamber is provided with a radial oil passage communicating with the axial oil passage, the thrust load acting on the rolling element can be reduced between the contact surfaces between the small-diameter cylindrical portion of the rolling element and the thrust plate and between the thrust plate and the lid. The rolling element can be stably rotated about the support shaft during the orbiting operation of the crawler belt. Further, the lubricating oil flowing in the radial oil passage can favorably lubricate the contact surfaces between the thrust plate and the lid.

In the case where the lubricating metal material used for the rolling elements is made of cast iron,
Since this cast iron has a self-lubricating property, the lubricating property between the rolling element and the thrust plate can be maintained.

[Brief description of the drawings]

FIG. 1 is an enlarged longitudinal sectional view showing an upper roller device according to the present embodiment.

FIG. 2 is an enlarged cross-sectional view of a main part showing an axial oil passage, a radial oil passage, and the like in FIG. 1 in an enlarged manner.

FIG. 3 is an enlarged perspective view showing the lid body in FIG. 1 alone.

FIG. 4 is an enlarged perspective view showing a single thrust plate according to a modification of the present embodiment.

FIG. 5 is a front view of a hydraulic shovel including an upper roller device according to the related art.

6 is an enlarged cross-sectional view as viewed from the direction indicated by arrows VI-VI in FIG. 5;

FIG. 7 is an enlarged longitudinal sectional view showing a conventional upper roller device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Track frame 8 Crawler belt 9 Lower roller device 22 Seal accommodation room 23 Floating seal (seal member) 31 Upper roller device 32 Support shaft 33 Roller (rolling element) 34 Large-diameter cylindrical portion 34A Contact surface 35 Small-diameter cylinder Part 35A Bush fitting hole 35B, 35C End surface 36 Flangeless bush (Bushing) 38 Thrust plate 38A, 39D Radial oil passage 39 Lid 39C Contact surface 40 Oil reservoir 41 Axial oil passage

Claims (4)

[Claims] 1. A support shaft, one end of which is fixed to a track frame of a tracked vehicle and the other end of which is a free end and which extends in an axial direction, and is rotatably supported by the support shaft for guiding a crawler belt. A rolling element provided with a bush fitting hole on the peripheral side, a bush provided to be fitted into the bush fitting hole of the rolling element, and the support shaft being slidably inserted on the inner peripheral side; A thrust plate fixedly provided on the other end of the support shaft and receiving a thrust load acting on the rolling element, and a thrust plate provided in a seal accommodating chamber between the support shaft and one end of the rolling element; A sealing member for sealing one side of the rolling element in the axial direction in a liquid-tight manner, and a lid provided on the other axial side of the rolling element and covering an oil reservoir formed on the other axial side of the rolling element. In the guide roller device for a tracked vehicle, the rolling element guides the crawler belt Therefore, a large-diameter cylindrical portion having an abutment surface with which the crawler belt abuts on the outer peripheral side is formed integrally with an inner peripheral side of an axially intermediate portion of the large-diameter cylindrical portion, and the bush fitting hole is formed on the inner peripheral side. The formed small-diameter cylindrical part is integrally molded using a lubricating metal material, and the small-diameter cylindrical part extends through the inside of the small-diameter cylindrical part in the axial direction, and the oil reservoir chamber and the seal accommodating chamber. A bushing formed as a cylindrical body without a flange, and the thrust plate is configured to be brought into contact with an end surface of the small-diameter cylindrical portion. Guide roller device for vehicles. 2. The guide roller device for a tracked vehicle according to claim 1, wherein the axial oil passage is located on an outer diameter side of the thrust plate and is opened at an end face of the small-diameter cylindrical portion. 3. The lid is in contact with the thrust plate in a state where it is press-fitted to the inner periphery on the other side in the axial direction of the large-diameter cylindrical portion, and the oil sump is provided between contact surfaces of the thrust plate and the lid. The guide roller device for a tracked vehicle according to claim 1 or 2, further comprising a radial oil passage communicating the chamber with the axial oil passage. 4. The guide roller device for a tracked vehicle according to claim 1, wherein the lubricating metal material used for the rolling elements is cast iron.