CN108691327B

CN108691327B - Excavator

Info

Publication number: CN108691327B
Application number: CN201810148478.7A
Authority: CN
Inventors: 山川尚宏; 大野岳志
Original assignee: Sumitomo SHI Construction Machinery Co Ltd
Current assignee: Sumitomo SHI Construction Machinery Co Ltd
Priority date: 2017-03-31
Filing date: 2018-02-13
Publication date: 2022-07-05
Anticipated expiration: 2038-02-13
Also published as: KR102448045B1; JP2018172091A; JP6732692B2; CN108691327A; KR20180111511A

Abstract

The invention provides an excavator capable of inhibiting sand from entering a gap between a carrier roller and a bracket. A shovel (100) is provided with: a crawler-type lower traveling body (1); an upper revolving body (3) mounted on the lower traveling body (1); and an attachment mounted on the upper slewing body (3). The lower traveling body (1) includes a carrier roller (1c) that supports the crawler belt (1b), a bracket (20) that can support the shaft (21) around which the carrier roller (1c) rotates, and a support shaft (21). The bracket (20) includes a 2 nd cylindrical portion (20b) extending in the axial direction of the shaft (21). The idler (1c) includes a 4 th cylindrical portion (1c4) extending in the axial direction of the shaft (21). A dust ring (26) is disposed in a gap between a 2 nd cylindrical portion (20b) and a 4 th cylindrical portion (1c4) in the radial direction of a shaft (21).

Description

Excavator

Technical Field

The present application claims priority based on japanese patent application No. 2017-072826, applied 3/31/2017. The entire contents of the application are incorporated by reference into this specification.

The present invention relates to an excavator having a crawler type lower traveling body.

Background

Conventionally, a shovel including a crawler type lower traveling body is known (see patent document 1). The lower traveling body has a track frame composed of a center frame and right and left side frames. And brackets for supporting the carrier rollers are arranged on the upper surfaces of the left and right frames. A shaft capable of supporting the rotation of the idler is mounted in the cradle. The left and right crawler belts are supported by the carrier rollers above the side frames. The excavator advances or retreats while rotating the left and right crawler belts.

Patent document 1: japanese laid-open patent publication No. 2004-314686

A part of the soil attached to the crawler moves with the rotation of the crawler and is accumulated on the side frame, and sometimes enters a gap between the idler and the carrier. Furthermore, when sand entering the gap between the idler and the carrier is solidified, adhesion between the idler and the carrier and adhesion between the seal rings are caused, and rotation of the idler may be inhibited. Further, the floating seal ring is damaged, and oil leakage may occur.

Disclosure of Invention

In view of the above, it is desirable to provide an excavator capable of suppressing entry of sand into a gap between a carrier roller and a bracket.

An excavator according to an embodiment of the present invention includes: a crawler-type lower traveling body; an upper slewing body mounted on the lower traveling body; and an attachment attached to the upper slewing body, wherein the lower traveling body includes a carrier roller for supporting a crawler belt, a shaft capable of supporting the carrier roller to rotate, and a bracket for supporting the shaft, the bracket includes an inner cylindrical portion extending in an axial direction of the shaft, the carrier roller includes an outer cylindrical portion extending in the axial direction of the shaft, and an intervening member is disposed in a gap between the inner cylindrical portion and the outer cylindrical portion in a radial direction of the shaft.

Effects of the invention

According to the above aspect, a shovel capable of suppressing entry of sand into a gap between a carrier roller and a bracket can be provided.

Drawings

Fig. 1 is a side view of an excavator according to an embodiment of the present invention.

Fig. 2 is a front view of the excavator of fig. 1.

Fig. 3 is a sectional view of a structural example of the idler support structure.

Fig. 4 is a cross-sectional view of a idler.

Fig. 5 is a cross-sectional view of the bracket.

Fig. 6 is a cross-sectional view of another structural example of an idler support structure.

In the figure: 1-lower traveling body, 1 a-frame, 1 b-track, 1b 1-track shoe, 1b 2-track link, 1b 3-pin, 1 c-idler, 1c 1-1 st tube section, 1c 2-2 nd tube section, 1c 3-3 rd tube section, 1c 4-4 th tube section, 1c 5-5 th tube section, 1 d-bogie wheel, 1M-revolving body traveling hydraulic motor, 1S-driven wheel, 2-revolving mechanism, 3-upper portion, 4-boom, 5-arm, 6-bucket, 7-arm cylinder, 8-arm cylinder, 9-bucket cylinder, 10-cab, 11-engine, 20-bracket, 20 a-1 st tube section, 20 b-2 nd tube section, 20 c-3 rd tube section, 21-shaft, 22-bush, 22 a-1 st bush, 22B-2 nd bush, 23-thrust plate, 23B-bolt, 24-cover, 24B-bolt, 24P-plug, 24S-O-ring, 25-floating seal ring, 25R-rotating side component, 25R 1-O-ring, 25R 2-seal ring, 25S-fixed side component, 25S 1-O-ring, 25S 2-seal ring, 26-dust ring, 26A-coil spring, 100-excavator, 200-roller support structure, H1-H5, H10-H12-hole.

Detailed Description

First, a shovel (excavator) according to an embodiment of the present invention will be described with reference to fig. 1 and 2. Fig. 1 is a side view of an excavator 100. Fig. 2 is a front view of the shovel 100.

The shovel 100 includes a crawler-type lower traveling body 1. An upper turning body 3 is mounted on the lower traveling body 1 via a turning mechanism 2. A boom 4 is attached to the upper slewing body 3. An arm 5 is attached to a tip of the boom 4, and a bucket 6 is attached to a tip of the arm 5. The boom 4, the arm 5, and the bucket 6 constitute an excavation attachment which is an example of an attachment. The boom 4, the arm 5, and the bucket 6 are hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9, respectively. A power source such as an engine 11 is mounted on the upper slewing body 3. A cab 10 is provided at the front end (+ X side end) of the left side (-Y side) of the upper revolving structure 3. In fig. 2, for the sake of clarity, the boom 5, the bucket 6, the boom cylinder 7, the boom cylinder 8, the bucket cylinder 9, and the like are not illustrated.

The lower traveling unit 1 is mainly composed of a frame 1a, a crawler 1b, a carrier roller 1c, a carrier wheel 1d, a traveling hydraulic motor 1M, driven wheels 1S, and the like. Fig. 2 shows a partial cross-sectional view of the lower runner 1 when viewed from the + X side on a plane containing the one-dot chain line L1 in fig. 1.

The frame 1a is a member forming a skeleton of the lower traveling body 1. The frame 1a has left frame portions 1a-L, right frame portions 1a-R, and center frame portions 1a-C connecting the left frame portions 1a-L and the right frame portions 1 a-R. The dot pattern DT in fig. 2 indicates sand deposited on the right frame portions 1a to R and the center frame portions 1a to C.

The crawler belt 1b is an endless track (crawler belt) rotationally driven by a traveling hydraulic motor 1M. The crawler 1b includes left and right crawlers 1b-L and 1 b-R.

The idler 1c is a driven roller disposed between the frame 1a and the crawler belt 1b on the upper side of the frame 1 a. The track roller 1d is a driven roller disposed between the frame 1a and the crawler 1b on the lower side of the frame 1 a. The idler 1c includes a plurality of left idlers 1c-L and a plurality of right idlers 1 c-R. The track roller 1d includes a plurality of left track rollers 1d-L and a plurality of right track rollers 1 d-R.

The traveling hydraulic motor 1M is attached to the rear end (-X-side end) of the frame 1 a. The traveling hydraulic motor 1M includes left and right traveling hydraulic motors 1M-L and 1M-R (not shown). The left traveling hydraulic motors 1M-L are attached to the rear ends of the left frame portions 1a-L, and the right traveling hydraulic motors 1M-R are attached to the rear ends of the right frame portions 1 a-R.

The driven wheel 1S is mounted on the front end (+ X-side end) of the frame 1 a. The driven wheels 1S include left driven wheels 1S-L and right driven wheels 1S-R (not shown). Left driven wheels 1S-L are mounted to the front ends of the left frame portions 1a-L, and right driven wheels 1S-R are mounted to the front ends of the right frame portions 1 a-R.

The left crawler belts 1b to L are respectively engaged with a drive sprocket coupled to a rotary shaft of the left traveling hydraulic motors 1M to L and left driven wheels 1S to L. The right crawler belts 1b to R are respectively engaged with a drive sprocket coupled to the rotary shafts of the right traveling hydraulic motors 1M to R and right driven wheels 1S to R.

With this configuration, in fig. 1, when the traveling hydraulic motor 1M rotates counterclockwise, the crawler belt 1b also rotates counterclockwise and the excavator 100 moves forward. Conversely, when the traveling hydraulic motor 1M rotates clockwise, the crawler belt 1b also rotates clockwise and the shovel 100 moves backward.

Next, a structural example of the idler support structure 200 will be described with reference to fig. 3 to 5. Fig. 3 is a sectional view of a structural example of the idler support structure 200. Fig. 4 is a sectional view of the idler 1c, and fig. 5 is a sectional view of the bracket 20. The range shown in fig. 3 corresponds to the range of the region R1 in fig. 2. That is, the idler support structure 200 of fig. 3 is a structure for supporting 1 idler of the plurality of right idlers 1 c-R. However, the structure for supporting the other idlers 1c also has the same structure as the idler support structure 200 of fig. 3. Therefore, the idler supporting structure 200 will be described below as being applicable to all idlers 1 c.

The one-dot chain line L2 of fig. 3 indicates the rotation axis of the idler 1 c. In fig. 3, the cross section of the member that rotates around the rotation axis is indicated by a forward-diagonal line pattern, and the cross section of the member that does not rotate is indicated by a reverse-diagonal line pattern. The dot pattern DT indicates the sand accumulated on the center frame portions 1 a-C.

The idler support structure 200 is capable of supporting the rotation of the idler 1c, and is mainly composed of a bracket 20, a shaft 21, a bush 22, a thrust plate 23, a cover body 24, a floating seal ring 25, a dust seal 26, and the like.

The idler 1c is engaged with a pair of track links 1b2 extending from a plurality of track shoes 1b1 constituting the track 1b toward the frame 1a, respectively. The pair of track links 1b2 of the track shoe 1b1 are coupled to the pair of track links 1b4 of the immediately preceding (+ X-side adjacent) track shoe by pins 1b3, respectively.

As shown in fig. 4, the idler 1c includes a 1 st tube section 1c1, a 2 nd tube section 1c2, a 3 rd tube section 1c3, a 4 th tube section 1c4, and a 5 th tube section 1c 5.

A hole H1 for passing the shaft 21 is formed in the 1 st cylinder portion 1c 1. A hole H2 for passing the shaft 21 and accommodating the rotation-side unit 25R of the floating seal ring 25 is formed in the 2 nd cylindrical portion 1c 2. A hole H3 for inserting the shaft 21 and accommodating the fixed-side unit 25S of the floating seal ring 25 and the end of the bracket 20 is formed in the 3 rd cylindrical portion 1c 3. A hole H4 for passing the shaft 21 and accommodating an end of the bracket 20 and accommodating the dust ring 26 is formed in the 4 th tube portion 1c 4. A hole H5 for accommodating the thrust plate 23 attached to the + Y side end portion of the shaft 21 is formed in the 5 th tube portion 1c 5.

The cradle 20 can support the idler 1c for rotation via a shaft 21. In the present embodiment, the brackets 20 are fixed to the upper surfaces of the center frame portions 1a-C using bolts or the like. The bracket 20 is supported so that the-Y side end of the shaft 21 cannot rotate relatively.

As shown in fig. 5, the bracket 20 includes a 1 st tubular portion 20a, a 2 nd tubular portion 20b, and a 3 rd tubular portion 20 c.

A hole H10 for passing the shaft 21 is formed in the 1 st cylindrical portion 20 a. A hole H11 for passing the shaft 21 is formed in the 2 nd cylindrical portion 20 b. A hole H12 for inserting the shaft 21 and accommodating the fixed side member 25S of the floating seal ring 25 is formed in the 3 rd cylinder portion 20 c.

The shaft 21 can support the idler 1c for relative rotation. the-Y side end of the shaft 21 is fixed to the bracket 20 so as not to rotate relatively. The thrust plate 23 is fastened to the + Y side end of the shaft 21 using 2 bolts 23B.

The bush 22 is a cylindrical member attached around the shaft 21, and is formed of, for example, resin, rubber, ceramic, metal, or the like. In the present embodiment, the bush 22 includes the 1 st bush 22a and the 2 nd bush 22b made of rubber. The bush 22 functions as a buffer member, and can alleviate the impact when the idler 1c collides with the shaft 21.

The thrust plate 23 is a member for receiving the thrust force in the axial direction of the idler 1 c. In the present embodiment, the thrust plate 23 is fastened to the + Y-side end of the shaft 21 using 2 bolts 23B. The thrust force in the + Y direction of the idler roller 1c is transmitted to the thrust plate 23 via the flange portion of the 1 st bush 22 a. The thrust force of the idler roller 1c in the-Y direction is transmitted to the thrust plate 23 via the cover 24.

The cover 24 is a member for covering the distal end (+ Y-side end) of the idler 1 c. In this embodiment, the cover body 24 is fastened to the end portion of the + Y side of the idler 1c using 2 bolts 24B. The internal space of the idler 1c is sealed on the-Y side by a floating seal ring 25 disposed around the shaft 21, and on the + Y side by a cover 24. An O-ring 24S is disposed between the inner wall of the 5 th tube part 1c5 of the idler 1c and the cover body 24. A plug 24P for sealing an inlet of lubricating oil such as gear oil is attached to the center of the cover 24. The worker can remove the plug 24P and inject the lubricating oil into the internal space of the idler 1 c.

The floating seal ring 25 is a member for preventing foreign matter from entering the inside of the idler 1 c. In this embodiment, foreign matter such as sand and soil passing through the gap G1 between the idler 1c and the bracket 20 is prevented from entering the inside of the idler 1 c. Specifically, the floating seal ring 25 includes a rotating-side element 25R and a fixed-side element 25S. The rotating-side unit 25R is constituted by an O-ring 25R1 made of rubber and a seal ring 25R2 made of metal. Further, the idler 1c is accommodated between the idler 1c and the shaft 21 in a hole H2 formed in a 2 nd tube portion 1c2 (refer to fig. 4) of the idler 1c, and rotates together with the idler 1 c. The stationary-side unit 25S is constituted by an O-ring 25S1 made of rubber and a seal ring 25S2 made of metal, as in the case of the rotary-side unit 25R. Further, the shaft 21 is accommodated in a hole H12 formed in the 3 rd cylindrical portion 20c (see fig. 5) of the bracket 20 between the bracket 20 and the shaft, and does not rotate together with the idler 1 c. During rotation of the idler 1c, the seal ring 25R2 of the rotating-side block 25R comes into contact with the seal ring 25S2 of the fixed-side block 25S to form a sliding portion SP. The sliding portion SP can block torque transmission from the rotating side unit 25R to the fixed side unit 25S, prevent outflow of lubricating oil from the inside of the idler 1c, and prevent intrusion of foreign matter into the inside of the idler 1 c.

The dust seal 26 is an example of an intervening member disposed between the idler 1c and the bracket 20. In the present embodiment, the dust ring 26 is formed of an elastomer. Specifically, it is formed of a resin. And may be formed of other materials such as rubber and metal. Further, the idler 1c is accommodated in a hole H4 formed in a 4 th tube portion 1c4 (refer to fig. 4) of the idler 1c between the idler 1c and the bracket 20, and rotates together with the idler 1 c. I.e. to the idler 1 c. The dust lip and the seal lip of the dust seal 26 contact the outer wall surface of the 2 nd cylindrical portion 20b (see fig. 5) of the bracket 20, and prevent foreign matter such as sand from reaching the floating seal ring 25. In the dust seal 26, the 4 th tube portion 1c4 of the idler 1c functions as an outer tube portion, and the 2 nd tube portion 20b of the bracket 20 functions as an inner tube portion. The dust ring 26 may be replaced with a bushing, sleeve, or other intervening component.

The dust ring 26 may not rotate together with the idler 1 c. I.e. can be mounted on the bracket 20. In this case, the dust lip and the seal lip of the dust seal 26 come into contact with the inner wall surface of the 4 th cylindrical portion 1c4 of the idler roller 1c, and foreign matter such as sand and soil is prevented from reaching the floating seal ring 25.

As described above, the dust seal 26 as an intervening member is disposed in the gap between the 2 nd cylindrical portion 20b of the bracket 20 as the inner cylindrical portion and the 4 th cylindrical portion 1c4 of the idler 1c as the outer cylindrical portion in the radial direction of the shaft 21 so as to fill the gap. The idler support structure 200 can inhibit or prevent the ingress of sand in the gap G1 between the idler 1c and the cradle 20 by plugging the gap G1 between the idler 1c and the cradle 20 with the dust ring 26. Therefore, the O-rings 25R1 and 25S1 of the floating seal ring 25 can be prevented from being damaged. As a result, the lubricant can be prevented from leaking from the damaged O-rings 25R1 and 25S 1. Further, the idler support structure 200 can prevent the seal ring 25R2 of the floating seal ring 25 from being separated from the seal ring 25S2 by preventing the O-rings 25R1 and 25S1 of the floating seal ring 25 from being damaged. Therefore, it is possible to prevent foreign matter such as sand from entering, accumulating, filling, or solidifying between the idler 1c and the shaft 21, and to prevent the idler 1c from being prevented from rotating. As a result, the idler support structure 200 can extend the life of the idler 1c and the track link 1b 2. This is because, if the track 1b rotates in a state in which the rotation of the idler 1c is hindered, the track link 1b2 slides on the surface of the idler 1c, resulting in uneven wear in the idler 1c and the track link 1b2, but the idler support structure 200 can suppress or prevent such uneven wear.

The dust ring 26 as an intervening member is preferably formed of an elastomer. Therefore, even when there is a variation in the size of the gap between the idler 1c and the bracket 20, the gap can be reliably closed. The dust ring 26 as an intervening member may also be formed of metal. This is because the durability is high as compared with a resin or the like.

Next, another structural example of the idler support structure 200 will be described with reference to fig. 6. Fig. 6 is a cross-sectional view of another example of a structure of the idler support structure 200, and corresponds to fig. 3. The idler support structure 200 of fig. 6 differs from the idler support structure 200 of fig. 3 in having a coil spring 26A in place of the dust ring 26, but is otherwise identical. Therefore, the description of the same parts will be omitted, and the description of different parts will be made.

The coil spring 26A is another example of an intervening member disposed between the idler 1c and the bracket 20. In the present embodiment, the coil spring 26A is a compression spring made of metal. However, it may be formed of other materials such as resin and rubber. Further, the idler 1c is accommodated in a hole H4 formed in a 4 th tube portion 1c4 (refer to fig. 4) of the idler 1c between the idler 1c and the bracket 20, and rotates together with the idler 1 c. I.e. to the idler 1 c. The coil spring 26A may or may not be in contact with the outer wall surface of the 2 nd cylindrical portion 20b (see fig. 5) of the bracket 20. In the coil spring 26A, the 4 th tube portion 1c4 of the idler 1c functions as an outer tube portion, and the 2 nd tube portion 20b of the bracket 20 functions as an inner tube portion.

The coil spring 26A may be configured not to rotate together with the idler 1 c. I.e. can be mounted on the bracket 20. In this case, the coil spring 26A may or may not contact the inner wall surface of the 4 th cylindrical portion 1c4 of the idler 1 c.

The idler support structure 200 of fig. 6 can inhibit or prevent entry of sand in the gap G1 between the idler 1c and the cradle 20 by plugging the gap G1 between the idler 1c and the cradle 20 with the coil spring 26A. Therefore, the same effects as those of the idler support structure 200 according to fig. 3 can be achieved.

In the idler support structure 200 of fig. 6, even if sand enters the inside of the coil spring 26A, the spiral shape of the coil spring 26A can delay the arrival of the sand at the floating seal ring 25. This is because the sand towards the floating seal ring 25 has to move along the spiral.

Also, the idler support structure 200 of fig. 6 can eject sand to the outside by the repulsive force of the coil spring 26A in the case where the coil spring 26A is compressed by the sand. For example, even when coil spring 26A is compressed to the + Y side by soil continuously fed onto center frame portions 1a to C with the rotation of crawler 1b, the soil can be returned to the-Y side by the repulsive force of coil spring 26A.

The coil spring 26A as an intervening member is preferably formed of metal. This is because the durability is high as compared with a resin or the like.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. The above embodiment can be applied to various modifications, replacements, and the like without departing from the scope of the present invention. Further, the features described with reference to the above embodiments may be combined as appropriate as long as they are not technically contradictory.

Claims

1. A shovel is provided with:

a crawler-type lower traveling body;

an upper slewing body mounted on the lower traveling body; and

an attachment mounted on the upper slewing body,

the lower traveling body includes a frame, an idler disposed between the frame and the crawler on an upper side of the frame to support the crawler, a shaft capable of supporting the idler, and a bracket supporting the shaft,

the bracket includes a base provided on an upper side of the frame, and an inner tube portion extending from the base to the idler side in an axial direction of the shaft,

the idler comprises an outer barrel portion extending in the axial direction of the shaft,

an intervening member is disposed in a gap between the inner cylindrical portion and the outer cylindrical portion in a radial direction of the shaft,

a floating seal ring is arranged in a gap between the shaft and the carrier roller.

2. The shovel of claim 1,

the intervening component is formed of an elastomer.

3. The shovel of claim 1 or 2, wherein,

the intervening component is formed of metal.

4. The shovel of any one of claims 1 to 3,

the intervention part is a dust ring.

5. The shovel of any one of claims 1 to 3,

the intervening component is a coil spring.