Crawler type running device for work machine

Abstract

To facilitate, in a crawler type running device, a replacement of a floating seal.SOLUTION: A crawler type running device for a work machine includes a crawler, a track frame, a rotating mechanism, a supporting mechanism, and a floating seal. The track frame includes a storing portion and an attaching portion. The attaching portion extends from the internal surface of the storing portion. The rotating mechanism includes a rotating body around which the crawler is wound. The rotating mechanism is placed outwardly relative to the attaching portion in the axial direction of the rotating body. The supporting mechanism supports the rotating mechanism in a rotatable manner. At least a part of the supporting mechanism is placed in the internal space of the storing portion. The supporting mechanism is attached to the attaching portion. The floating seal seals a space between the rotating mechanism and the supporting mechanism. The supporting mechanism includes a seal cover. The seal cover covers the floating seal in the axial direction from the internal side of the floating seal. The seal cover is placed inwardly relative to the attaching portion in the axial direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a crawler traveling device for a work machine.

Background Art

[0002] Some work machines are equipped with a crawler traveling device. For example, in the work machine of Patent Document 1, the crawler traveling device includes a crawler, a sprocket, a housing, a speed reducer, a traveling motor, and a track frame. The crawler is wound around the sprocket. The traveling motor is connected to the sprocket via a speed reducer. The housing is attached to the track frame. The traveling motor and the speed reducer are disposed inside the housing and the track frame and are supported by the housing.

[0003] Also, the crawler traveling device is provided with a floating seal. The floating seal is disposed between the sprocket and the housing. The floating seal seals between the sprocket and the housing. Thereby, the intrusion of foreign matters such as earth and sand into the housing is suppressed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The above-described floating seal may be damaged due to wear. In that case, it is necessary to disassemble the crawler traveling device and replace the floating seal. Specifically, first, the crawler is cut and removed from the sprocket. Also, the speed reducer is disassembled and removed from the housing. Then, the floating seal is replaced.

[0006] Thus, in a conventional crawler travel device, in order to replace the floating seal, it is necessary to disassemble the crawler travel device and remove the crawler, sprocket, speed reducer, etc., and the work is complicated. The object of the present disclosure is to facilitate the replacement of the floating seal in the crawler travel device.

Means for Solving the Problems

[0007] The crawler travel device of a work machine according to one aspect of the present disclosure includes a crawler, a track frame, a rotation mechanism, a support mechanism, and a floating seal. The track frame supports the crawler. The track frame includes a storage portion and an attachment portion. The storage portion has an internal space. The attachment portion extends from the inner surface of the storage portion. The rotation mechanism includes a rotating body around which the crawler is wound. The rotation mechanism is disposed outside the attachment portion in the axial direction of the rotating body. The support mechanism rotatably supports the rotation mechanism. At least a part of the support mechanism is disposed in the internal space. The support mechanism is attached to the attachment portion. The floating seal seals between the rotation mechanism and the support mechanism. The support mechanism includes a seal cover. The seal cover covers the floating seal from the inner side of the floating seal in the axial direction. The seal cover is disposed inside the attachment portion in the axial direction.

[0008] In the crawler travel device according to the present disclosure, by removing the seal cover from the support mechanism, access to the floating seal becomes possible. Further, the seal cover is disposed inside the attachment portion in the axial direction. Therefore, the seal cover can be removed from the inside of the attachment portion without removing the rotation mechanism disposed outside the attachment portion. Accordingly, the floating seal can be easily replaced by removing the seal cover without disassembling the crawler and the rotation mechanism.

Effects of the Invention

[0009] According to the present disclosure, in the crawler travel device, the replacement of the floating seal becomes easy.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0011] Hereinafter, the crawler traveling device of the working machine according to the embodiment will be described with reference to the drawings. Fig. 1 is a side view of the working machine 1 according to the embodiment. Fig. 2 is a top view of the working machine 1. In the present embodiment, the working machine 1 is an excavator such as a hydraulic excavator or an electric excavator.

[0012] As shown in Figs. 1 and 2, the working machine 1 includes a working device 3, a slewing body 4, and a pair of left and right crawler traveling devices 5 and 6. The working device 3 is operably attached to the slewing body 4. The working device 3 includes a boom 11, an arm 12, and a bucket 13. The boom 11 is rotatably attached to the slewing body 4. The arm 12 is rotatably attached to the boom 11. The bucket 13 is rotatably attached to the arm 12.

[0013] The crawler travel device 5 includes a first rotation mechanism 21, a second rotation mechanism 22, a crawler 23, and a track frame 24. The track frame 24 supports the crawler 23 via a plurality of idler wheels 25. In the drawings, only one of the plurality of idler wheels 25 is labeled 25, and the labels for the other idler wheels 25 are omitted.

[0014] The first rotation mechanism 21 includes a first rotating body 26. The second rotation mechanism 22 includes a second rotating body 27. In the present embodiment, the first rotating body 26 is a sprocket, and the second rotating body 27 is an idler. The crawler 23 is wound around the first rotating body 26 and the second rotating body 27. Although not shown, the crawler 23 includes a plurality of crawler plates connected to each other. When the crawler 23 is driven, the work machine 1 travels.

[0015] Figure 3 is a sectional view taken along line III-III in Figure 1. As shown in Figure 3, the first rotation mechanism 21 includes a first hole 28. The first hole 28 extends in the axial direction of the first rotating body 26. As shown in Figure 2, the axis Ax1 of the first rotating body 26 extends in the left-right direction of the work machine 1. That is, the axial direction of the first rotating body 26 coincides with the left-right direction of the work machine 1. The axial direction of the first rotating body 26 is the same as the axial direction of the left and right crawler travel devices 5, 6.

[0016] The crawler travel device 5 includes a support mechanism 30. The support mechanism 30 is fixed to the track frame 24. A part of the support mechanism 30 is disposed within the first hole 28. The support mechanism 30 rotatably supports the first rotation mechanism 21. The support mechanism 30 includes a support shaft 31, a travel motor 32, and a seal cover 33. The support shaft 31 is disposed within the first hole 28 of the first rotation mechanism 21. The support shaft 31 extends in the axial direction of the first rotating body 26. The support shaft 31 is coaxially disposed with the first rotating body 26. Bearings 34, 35 are disposed between the outer peripheral surface of the support shaft 31 and the inner peripheral surface of the first hole 28. The support shaft 31 rotatably supports the first rotation mechanism 21 via the bearings 34, 35. The support shaft 31 includes a second hole 36. The second hole 36 extends in the axial direction.

[0017] The traveling motor 32 is disposed within the second hole 36 of the support shaft 31. The traveling motor 32 rotates the first rotation mechanism 21. The traveling motor 32 is, for example, an electric motor. Alternatively, the traveling motor 32 may be a hydraulic motor. The traveling motor 32 includes a drive shaft 37 and a motor housing 38. The drive shaft 37 extends in the axial direction. The drive shaft 37 is coaxially disposed with the first rotating body 26. The drive shaft 37 is connected to the first rotation mechanism 21. The motor housing 38 supports the drive shaft 37. The seal cover 33 will be described in detail later.

[0018] The first rotation mechanism 21 includes a final reduction gear 41, a rotating body housing 42, and a boss 43. The final reduction gear 41 is connected to the drive shaft 37. The final reduction gear 41 reduces the rotation of the drive shaft 37 and transmits it to the first rotating body 26. The final reduction gear 41 includes a first reduction gear 44, a second reduction gear 45, and a third reduction gear 46. The first reduction gear 44, the second reduction gear 45, and the third reduction gear 46 include, for example, a planetary gear mechanism. However, the first reduction gear 44, the second reduction gear 45, and the third reduction gear 46 may include a reduction mechanism other than the planetary gear mechanism. In FIG. 3, the first reduction gear 44, the second reduction gear 45, and the third reduction gear 46 are shown in a simplified manner.

[0019] The first reduction gear 44 and the second reduction gear 45 are disposed within the second hole 36 of the support shaft 31. The first reduction gear 44 is disposed outside the traveling motor 32 in the axial direction. The first reduction gear 44 is connected to the drive shaft 37. The second reduction gear 45 is disposed outside the first reduction gear 44 in the axial direction. The second reduction gear 45 is connected to the first reduction gear 44. The third reduction gear 46 is disposed outside the second reduction gear 45 in the axial direction. The third reduction gear 46 is disposed outside the support shaft 31 in the axial direction. The third reduction gear 46 is connected to the second reduction gear 45.

[0020] The rotating body housing 42 is disposed outside the first rotating body 26 in the axial direction. The rotating body housing 42 is connected to the first rotating body 26. The third speed reducer 46 is disposed within the rotating body housing 42. The third speed reducer 46 is supported by the rotating body housing 42. The final speed reducer 41 transmits the rotation of the drive shaft 37 to the rotating body housing 42. The rotating body housing 42 is connected to the first rotating body 26. The rotating body housing 42 rotates integrally with the first rotating body 26. When the rotating body housing 42 rotates, the first rotating body 26 rotates.

[0021] The boss 43 is disposed inside the first rotating body 26 in the axial direction. The boss 43 is connected to the first rotating body 26. The boss 43 rotates integrally with the first rotating body 26. The above-described first hole 28 is provided inside the first rotating body 26, the rotating body housing 42, and the boss 43. The first hole 28 is filled with lubricating oil.

[0022] The track frame 24 includes a storage portion 51 and a mounting portion 52. The storage portion 51 is disposed inside the first rotating body 26 in the axial direction. The storage portion 51 has an internal space S1. A part of the support mechanism 30 is disposed in the internal space S1 of the storage portion 51. At least a part of the traveling motor 32 is disposed in the internal space S1 of the storage portion 51. The storage portion 51 includes a wall portion 53 and an inner cover 54. FIG. 4 is a perspective view of the crawler traveling device 5 with the inner cover 54 removed, viewed from the inside in the axial direction. FIG. 5 is a side view of the crawler traveling device 5 with the inner cover 54 removed, viewed from the inside in the axial direction.

[0023] As shown in FIGS. 4 and 5, the wall portion 53 covers the internal space S1 from the front-rear direction and the up-down direction. The wall portion 53 includes a first wall portion 55 and a second wall portion 56. The first wall portion 55 has a curved plate-like shape. The first wall portion 55 is disposed behind, above, and below the internal space S1. The second wall portion 56 is disposed in front of the internal space S1. The second wall portion 56 includes a hole 57. A cable 58 connected to the traveling motor 32 passes through the hole 57.

[0024] As shown in FIG. 3, the inner cover 54 is disposed inside in the axial direction of the internal space S1. The inner cover 54 has a plate-like shape extending in the vertical direction and the front-rear direction. The inner cover 54 is detachably attached to the wall portion 53. For example, the inner cover 54 is attached to the wall portion 53 by bolts 59 and 60.

[0025] The attachment portion 52 extends in the vertical direction and the front-rear direction from the inner surface of the wall portion 53. The attachment portion 52 has a plate-like shape. The attachment portion 52 is fixed to the wall portion 53. For example, the attachment portion 52 is fixed to the wall portion 53 by welding. The attachment portion 52 is disposed inside the first rotating body 26 in the axial direction. That is, the first rotating body 26 is disposed outside the attachment portion 52 in the axial direction. The attachment portion 52 includes a first opening 61. The above-described support mechanism 30 and the boss 43 of the first rotation mechanism 21 extend through the first opening 61. The support mechanism 30 is attached to the attachment portion 52.

[0026] The crawler travel device 5 includes a floating seal 62. The floating seal 62 is disposed between the first rotation mechanism 21 and the support mechanism 30 in the axial direction. The floating seal 62 seals between the first rotation mechanism 21 and the support mechanism 30. Specifically, the floating seal 62 is disposed between the boss 43 and the seal cover 33. The floating seal 62 has an outer diameter smaller than that of the first opening 61 of the attachment portion 52. At least a part of the floating seal 62 is located inside the attachment portion 52 in the axial direction. The support shaft 31 has an outer diameter smaller than that of the floating seal 62. The support shaft 31 is disposed inside the floating seal 62 in the radial direction.

[0027] Figure 6 is an enlarged view showing the structure near the floating seal 62. As shown in Figure 6, the floating seal 62 includes a first seal 63 and a second seal 64. The first seal 63 is attached to the boss 43. The second seal 64 is attached to the seal cover 33. Specifically, a first recess 65 is provided at the end of the boss 43 on the inner side in the axial direction. The first seal 63 is attached to the first recess 65. The seal cover 33 is provided with a second recess 66. The second seal 64 is attached to the second recess 66.

[0028] The first seal 63 includes a first O-ring 67 and a first metal seal ring 68. The second seal 64 includes a second O-ring 69 and a second metal seal ring 70. Due to the elastic force of the first O-ring 67 and the second O-ring 69, the first metal seal ring 68 and the second metal seal ring 70 are in close contact. Therefore, when the first rotating body 26 rotates, in the floating seal 62, the first metal seal ring 68 and the second metal seal ring 70 slide while being in close contact. Thereby, the support mechanism 30 rotatably supports the first rotating mechanism 21, and the intrusion of foreign matters such as earth and sand through between the support mechanism 30 and the first rotating mechanism 21 is suppressed.

[0029] The first rotating mechanism 21 includes a flange portion 71. The flange portion 71 extends outward in the radial direction of the first rotating mechanism 21 from the boss 43. The flange portion 71 faces the mounting portion 52 from the outside in the axial direction. The flange portion 71 forms a labyrinth structure between the boss 43 and the mounting portion 52. Thereby, the intrusion of foreign matters such as earth and sand through between the support mechanism 30 and the first rotating mechanism 21 is further suppressed.

[0030] The above-mentioned seal cover 33 is arranged inside the floating seal 62 in the axial direction. The floating seal 62 is arranged between the boss 43 and the seal cover 33 in the axial direction. The seal cover 33 covers the floating seal 62 from the inside of the floating seal 62 in the axial direction. The seal cover 33 has an outer diameter larger than that of the first opening 61 of the mounting portion 52. The seal cover 33 is arranged inside the mounting portion 52 in the axial direction. The seal cover 33 is detachably attached to the mounting portion 52. The seal cover 33 is attached to the mounting portion 52 by a plurality of first bolts 72. In the drawings, only one of the plurality of first bolts 72 is labeled 72, and the labels of the other first bolts 72 are omitted.

[0031] The seal cover 33 is separate from the support shaft 31. The seal cover 33 is arranged inside the support shaft 31 in the axial direction. The seal cover 33 is detachably attached to the support shaft 31. The seal cover 33 is arranged inside the motor housing 38 in the axial direction. The seal cover 33 is detachably attached to the motor housing 38. The seal cover 33 is attached to the support shaft 31 and the motor housing 38 by a common plurality of second bolts 73. In the drawings, only one of the plurality of second bolts 73 is labeled 73, and the labels of the other second bolts 73 are omitted.

[0032] As shown in FIG. 5, the seal cover 33 has an annular shape. The seal cover 33 includes a second opening 74. As shown in FIG. 3, the traveling motor 32 is exposed to the internal space S1 of the truck frame 24 through the second opening 74. As shown in FIGS. 5 and 6, the seal cover 33 includes an outer diameter portion 75, an inner diameter portion 76, and an intermediate portion 77. The outer diameter portion 75 is located radially outside the floating seal 62. The inner diameter portion 76 is located radially inside the floating seal 62. The intermediate portion 77 is located between the outer diameter portion 75 and the inner diameter portion 76 in the radial direction.

[0033] The seal cover 33 is attached to the attachment portion 52 at the outer diameter portion 75. As shown in FIG. 6, bolt holes 78 are provided in the outer diameter portion 75. Bolt holes 79 may be provided in the attachment portion 52. The outer diameter portion 75 is attached to the attachment portion 52 by a first bolt 72 passed through the bolt hole 78 in the outer diameter portion 75 and the bolt hole 79 in the attachment portion 52. The first bolt 72 is inserted into the bolt hole 78 in the outer diameter portion 75 and the bolt hole 79 in the attachment portion 52 from the inside of the seal cover 33 in the axial direction.

[0034] The seal cover 33 is attached to the support shaft 31 at the inner diameter portion 76. Bolt holes 81 are provided in the inner diameter portion 76. Bolt holes 82 are provided in the support shaft 31. Bolt holes 83 are provided in the motor housing 38. The inner diameter portion 76 is attached to the support shaft 31 by a second bolt 73 passed through the bolt hole 81 in the inner diameter portion 76, the bolt hole 83 in the motor housing 38, and the bolt hole 82 in the support shaft 31. The second bolt 73 is inserted into the bolt hole 81 in the inner diameter portion 76, the bolt hole 83 in the motor housing 38, and the bolt hole 82 in the support shaft 31 from the inside of the seal cover 33 in the axial direction.

[0035] In the crawler travel device 5 according to the present embodiment described above, when replacing the floating seal 62, first, as shown in FIGS. 4 and 5, the inner cover 54 is removed from the track frame 24. Thereby, access to the seal cover 33 becomes possible from the inside of the track frame 24. Next, the seal cover 33 is removed from the attachment portion 52 and the support shaft 31. Thereby, as shown in FIG. 7, the floating seal 62 is exposed, and access to the floating seal 62 becomes possible from the inside of the track frame 24. Therefore, the floating seal 62 can be easily replaced without cutting the crawler 23 or removing the first rotation mechanism 21 from the outside of the track frame 24. Note that the configuration of the crawler travel device 6 is the same as that of the crawler travel device 5, and thus a detailed description thereof is omitted.

[0036] As described above, one embodiment of the present invention has been explained. However, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention.

[0037] The working machine 1 is not limited to an excavator and may be other machines such as a bulldozer or a dump truck. The structure of the first rotating mechanism 21 is not limited to that of the above-described embodiment and may be changed. For example, the number of speed reducers is not limited to three. The number of speed reducers may be less than three or more than three. The first rotating body 26 is not limited to a sprocket and may be an idler. The structures of the floating seal 62 and the seal cover 33 described above may be applied to the second rotating mechanism 22.

Industrial Applicability

[0038] According to the present disclosure, in a crawler traveling device, the replacement of the floating seal becomes easy.

Explanation of Signs

[0039] 1: Working machine, 5: Crawler traveling device, 21: First rotating mechanism, 23: Crawler, 26: First rotating body, 24: Truck frame, 30: Support mechanism, 31: Support shaft, 32: Traveling motor, 33: Seal cover, 37: Drive shaft, 38: Motor housing 43: Boss, 51: Storage part, 52: Attachment part, 61: First opening, 62: Floating seal, 71: Flange part, 75: Outer diameter part, 76: Inner diameter part, Ax1: Axis

Claims

1. A crawler travel device for a work machine, including a crawler, a storage part having an internal space, and a mounting part extending from an inner surface of the storage part, and a track frame that supports the crawler, including a rotating body around which the crawler is wound, and a rotating mechanism disposed outside the mounting part in the axial direction of the rotating body, a support mechanism at least partially disposed in the internal space, attached to the mounting part, and rotatably supporting the rotating mechanism, a floating seal that seals between the rotating mechanism and the support mechanism, and comprising, the support mechanism includes a seal cover that covers the floating seal from the inside of the floating seal in the axial direction, the seal cover is disposed inside the mounting part in the axial direction, a crawler travel device.

2. The seal cover is detachably attached to the mounting part, The crawler travel device according to claim 1.

3. The mounting part includes an opening, The rotating mechanism includes a boss extending from the rotating body inward in the axial direction through the opening, The crawler travel device according to claim 1.

4. The floating seal is disposed between the boss and the seal cover, The crawler travel device according to claim 3.

5. The seal cover has an outer diameter larger than that of the opening, The crawler travel device according to claim 3.

6. The floating seal has an outer diameter smaller than that of the opening, The crawler travel device according to claim 3.

7. The rotating mechanism includes a flange portion extending in the radial direction of the rotating mechanism from the boss, The flange portion faces the mounting part from the outside of the mounting part in the axial direction, The crawler travel device according to claim 3.

8. The support mechanism includes a support shaft disposed in the rotating mechanism and rotatably supporting the rotating mechanism, The seal cover is disposed inside the support shaft in the axial direction, The crawler travel device according to claim 1.

9. The seal cover is detachably attached to the support shaft, The crawler travel device according to claim 8.

10. The support shaft has an outer diameter smaller than that of the floating seal, The crawler travel device according to claim 8.

11. The seal cover, an outer diameter portion located radially outside the floating seal, an inner diameter portion located radially inward of the floating seal; including; the seal cover is attached to the attachment portion at the outer diameter portion and attached to the support shaft at the inner diameter portion; The crawler travel device according to claim 8.

12. The support mechanism includes a travel motor disposed in the internal space of the storage portion; The travel motor includes a drive shaft connected to the rotation mechanism and a motor housing that supports the drive shaft; The seal cover is disposed inside the motor housing in the axial direction; The crawler travel device according to claim 8.

13. The seal cover is detachably attached to the motor housing; The crawler travel device according to claim 12.

14. The seal cover connects the support shaft and the motor housing by bolts and is attached to the support shaft and the motor housing; The crawler travel device according to claim 13.

Images