Caterpillar track device and caterpillar track

Abstract

The invention provides a caterpillar track device and a caterpillar track provided with the caterpillar track device, wherein a caterpillar track can be formed at low cost and a lubricant can be properly sealed. The chain rail device (12) is provided with an embedding part (45) for embedding the sealing component (43) at at least one of the end part of the bush (21) and the periphery of the second hole part (36) of the chain rail (20) which is opposite to the end part of the bush (21) with a gap (46) being arranged between the end part of the bush (21) and the periphery of the second hole part (36) of the chain rail (20). As a result of axial deformation of the seal member (43) fitted in the fitting section (45), the end of the bush (21) can be supported by a support member that is harder than the seal member (43).

Description

Technical Field

[0001] The invention relates to a chain track device and a crawler belt comprising the chain track device, wherein a plurality of chain tracks of the chain track device are connected through bushings and pins. Background Art

[0002] Conventionally, a track link device in which a plurality of track links are connected in an annular manner by bushings and pins is used in a crawler track used in a crawler type vehicle such as a hydraulic excavator (for example, refer to Patent Documents 1 and 2).

[0003] In order to extend the service life of the chain track device, lubricant such as grease or oil is usually sealed in the gap between the pin and the bushing. In order to prevent the sealed lubricant from leaking and contaminating the soil, a sealing device needs to be provided at the end of the contact surface between the pin and the bushing.

[0004] As a general sealing device, for example, as described in Patent Document 1, a countersunk portion having a diameter larger than that of the pin is provided on the inner periphery of the pin hole of the chain rail, a sealing component having a W-shaped cross section is mounted on the countersunk portion, and is arranged so that the entire bushing end contacts the sealing component.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-118271

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 8-128076 Summary of the invention

[0009] In the above structure, the depth of the counterbore portion required for the bushing needs to be set, and a pin press-in allowance required for press-in the pin into the link rail is required, so the link rail needs to have a thickness around the pin hole.

[0010] For example, in the case where the base material of the link rail is manufactured by a forging or casting method as in the structure described in Patent Document 1, a mountain-shaped boss portion having a thicker portion around the pin hole can be formed, but in the case where the link rail is manufactured from a rolled material as described in Patent Document 2, not only the area around the pin hole is increased, but the entire rolled material becomes thicker, and the volume of the base material increases, resulting in an increase in cost. In addition, in the sealing component having a W-shaped cross section, since its structure bears all loads in the rotation axis direction of the link rail, not only the size must be increased, but also the wear of the sealing component is likely to occur, which is one of the reasons for affecting the life of the link rail device.

[0011] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a link rail device that can form a link rail at low cost and can appropriately seal a lubricant, and a crawler including the link rail device.

[0012] The invention according to claim 1 is a chain rail device, which includes: a plurality of chain rails, which are formed of rolled materials and have a plurality of hole portions; bushings, which are pressed into the hole portions of the chain rails; pins, which connect one chain rail to another chain rail by pressing a bushing pressed into the hole portion of one chain rail into the hole portion of another chain rail; and an annular sealing component, which is used to seal the lubricant sandwiched between the pin and the bushing, and an embedding portion for embedding the sealing component is formed at least one of the end of the bushing and the periphery of the hole portion of the chain rail opposite to the end of the bushing with a gap, and due to axial deformation of the sealing component embedded in the embedding portion, the end of the bushing can be supported by a supporting component harder than the sealing component.

[0013] The invention according to claim 2 is a chain rail device, wherein the chain rail device embedding portion according to claim 1 is a groove portion formed in at least one of the end surface of the bushing and the side surface portion around the hole portion of the chain rail.

[0014] The invention according to claim 3 is a chain rail device, wherein the fitting portion of the chain rail device according to claim 1 is a chamfered portion formed at least one of an edge of the hole portion of the bushing and an edge of the hole portion of the chain rail.

[0015] The invention according to claim 4 is a crawler, which includes: a chain track device according to any one of claims 1 to 3, wherein a plurality of chain tracks are connected in an annular manner by bushings and pins; and a shoe mounted on each chain track of the chain track device.

[0016] According to the invention of claim 1, the chain rail can be formed at low cost, and the lubricant can be appropriately sealed.

[0017] According to the invention of claim 2, the embedding portion can be easily formed, and by setting the shape of the embedding portion and the allowable deformation amount of the sealing component, it is easy to achieve a structure in which the end of the bushing contacts the support component through axial deformation of the sealing component embedded in the embedding portion.

[0018] According to the invention of claim 3, the embedding portion can be easily formed, and by setting the shape of the embedding portion and the allowable deformation amount of the sealing component, it is easy to achieve a structure in which the end of the bushing contacts the support component through axial deformation of the sealing component embedded in the embedding portion.

[0019] According to the invention of claim 4, a low-cost and highly reliable crawler track capable of maintaining performance for a long period of time can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a longitudinal sectional front view showing a link rail device according to the present invention and a first embodiment of the link rail device.

[0021] 2( a ) is a longitudinal sectional front view showing a part of the chain rail device in an enlarged manner, and FIG2( b ) is a longitudinal sectional front view showing a state where a bushing and a support member are in contact due to deformation of a sealing member.

[0022] FIG. 3 (a) is a perspective view showing the link rail from one side, and FIG. 3 (b) is a perspective view showing the link rail from the other side.

[0023] Figure 4 It is a longitudinal sectional side view showing a part of the crawler track.

[0024] Figure 5 1 is a perspective view showing an example of a rolled material forming the above-mentioned link rail.

[0025] Figure 6 It is a perspective view showing a part of the crawler belt.

[0026] Figure 7 It is a side view showing a crawler-type vehicle equipped with the crawler track.

[0027] Figure 8 1 is a longitudinal sectional front view showing a part of a second embodiment of a chain track device according to the present invention.

[0028] Fig. 9 1 is a longitudinal sectional front view showing a part of a third embodiment of a chain track device according to the present invention. DETAILED DESCRIPTION

[0029] The present invention is based on Figures 1 to 7 The first embodiment shown, Figure 8 The second embodiment shown and Figure 7 The third embodiment shown will be described in detail.

[0030] Below, according to Figures 1 to 7 The embodiments shown are used to explain the present invention in detail.

[0031] Figure 7 1 denotes a crawler vehicle. In the present embodiment, an example of the crawler vehicle 1 includes a hydraulic excavator as a working machine. In the crawler vehicle 1, an upper rotating body 3 is rotatably provided on a lower traveling device 2, and a working device 4, a cab 5 for an operator to sit in, etc. are mounted on the upper rotating body 3.

[0032] In the travel device 2, the sprocket 7 driven by the travel motor is pivotally supported on one end of the crawler frame 6 respectively arranged on the left and right parts of the machine body, the idler wheel 8 is pivotally supported on the other end, a plurality of lower rollers 9 are pivotally supported on the lower side, a plurality of upper rollers 10 are pivotally supported on the upper side, and the crawler 11 is respectively wound around the sprocket 7, the idler wheel 8, the lower roller 9 and the upper roller 10 installed on the left and right parts of the machine body.

[0033] like Figure 6 As shown, the crawler 11 is composed of a shoe (shoe plate) 13 as a circling member suspended and mounted on a circular chain rail device 12 that is symmetrical or substantially symmetrically arranged. In addition, the shoe 13 is configured to be circulated by the chain rail device 12.

[0034] The track device 12 is composed of a plurality of plate-shaped track rails (track track rails) 20 connected by cylindrical bushings 21 and cylindrical pins 22. In the present embodiment, the plurality of track rails 20 are sequentially connected to both ends of the bushings 21 and the pins 22. Therefore, a pair of left and right track rails 20, 20 and another pair of left and right track rails 20, 20 are connected by bushings 21 and pins 22. That is, in the example shown, for each shoe 13, a row of track devices 12 is provided at the center portion of the shoe 13 in the left-right direction.

[0035] The link rail 20 shown in FIG. 3( a) and FIG. 3( b) is arranged so that the thickness direction is the left-right direction, the longitudinal direction is the front-back direction, and the transverse direction or the width direction is the up-down direction. The link rail 20 has a flat link rail main body 24 with the largest thickness and a flat first connection part 25 and a second connection part 26 with a thickness smaller than that of the link rail main body 24. The first connection part 25 and the second connection part 26 are located on the opposite side to each other with the link rail main body 24 as a reference. The first connection part 25 constitutes one end of the link rail 20, and the second connection part 26 constitutes the other end of the link rail 20. In this embodiment, the first connection part 25 is displaced in a step-like manner in one direction in the thickness direction relative to the link rail main body 24, and the second connection part 26 is displaced in a step-like manner in the other direction in the thickness direction. That is, the first connection part 25 and the second connection part 26 are alternated in the thickness direction with the link rail main body 24 as a reference. The link rail 20 is symmetrical or approximately symmetrical up and down, and the left and right link rails 20 are formed in the same shape.

[0036] like Figure 1As shown. The chain rail body 24 is a portion that connects the chain rail device 12 or the chain rail 20 to the shoe 13. In the present embodiment, the chain rail 20 and the shoe 13 are connected to each other by a mounting bolt 27 as a connecting member. For example, in the chain rail body 24, a bolt hole portion 28 is formed from the lower part to the upper part along the up-down direction which is a direction orthogonal to the rotation axis direction of the chain rail 20, and the bolt hole portion 28 has a threaded portion for screwing the mounting bolt 27 inside. In the example shown, the bolt hole portions 28 are respectively formed on the first connection portion 25 side of the chain rail body 24, that is, one end portion side, and the second connection portion 26 side, that is, the other end portion side. The chain rail 20 and the shoe 13 are connected to each other by inserting the mounting bolt 27 inserted from the mounting hole 29 formed in the shoe 13 into the bolt hole portion 28 and screwing it. The connection structure between the chain rail 20 and the shoe 13 can be arbitrarily configured and is not limited to the structure connected using the mounting bolt 27, for example, it can be connected by welding or the like.

[0037] As shown in Figure 3(a) and Figure 3(b) and Figure 6 As shown, the first connection portion 25 is also called an inner connection portion, and is located on the inner side in the thickness direction of the plurality of chain rails 20 connected to each other. In addition, the second connection portion 26 is also called an outer connection portion, and is located on the outer side in the thickness direction of the plurality of chain rails 20 connected to each other. That is, in the connected chain rails 20, the second connection portion 26 of another chain rail 20 overlaps the outer side of the first connection portion 25 of one chain rail 20.

[0038] The first connection portion 25 is formed with a first hole portion 35, which is a hole portion into which the bushing 21 is press-fitted. The first hole portion 35 is formed in a circular shape and passes through the first connection portion 25 in the thickness direction. The first hole portion 35 has a small press-fit margin relative to the outer diameter of the bushing 21. That is, the first connection portion 25 is formed to have a thickness that can ensure a press-fit margin for the bushing 21, and has a substantially constant thickness.

[0039] The second connection portion 26 has a second hole portion 36, which is a hole portion into which the pin 22 is press-fitted. The second hole portion 36 is formed in a circular shape and passes through the second connection portion 26 in the thickness direction. The second hole portion 36 has a small amount of press-fit margin relative to the outer diameter of the pin 22. That is, the second connection portion 26 is formed to have a thickness that can ensure the press-fit margin of the pin 22, and has a substantially constant thickness. In the present embodiment, the thickness of the second connection portion 26 is set to be greater than the thickness of the first connection portion 25.

[0040] The diameter of the second hole portion 36 is smaller than the diameter of the first hole portion 35. A recess 38 is formed in a stepped shape around the second hole portion 36, and the end of the bushing 21 is inserted therein. The recess 38 is formed along the outer circumference of the second hole portion 36 on the inner side of the second connecting portion 26, that is, on the side of the other chain rail 20 opposite to the first connecting portion 25. The outer diameter of the recess 38 is formed to be slightly larger than the outer diameter of the bushing 21. The bottom surface portion 39 of the recess 38 constitutes a side surface portion of the end of the chain rail 20 opposite to the bushing 21.

[0041] In addition, in this embodiment, the chain rail 20 is Figure 5 The step shape of the link rail body 24, the first connecting portion 25 and the second connecting portion 26 (FIG. 3(a)) in the thickness direction is formed by rolling the material 40. The shape F of the entire link rail 20 can be obtained by laser cutting or punching by cutting out only the surrounding portion from the rolled material at each width corresponding to the height of the link rail 20 (FIG. 3(a)).

[0042] It should be noted that the first hole portion 35 and the second hole portion 36 shown in FIG. 3 (a) and FIG. 3 (b) can be formed in the rolled material 40 ( Figure 5 ) is processed in any step before and after cutting out the chain rail 20. Figure 4 The bolt hole portion 28 shown is formed by cutting the rolled material 40 ( Figure 5 ) is processed after the chain track 20 is cut out.

[0043] Figure 1 The bushing 21 shown is pressed between the first hole portions 35 of the left and right rails 20. Both ends of the bushing 21 protrude from the outer surfaces of the left and right rails 20 and are inserted into the side portions of the rails 20 overlapping the outer sides of the rails 20, and in this embodiment, into the recesses 38.

[0044] The pin 22 is pressed into the second hole portion 36 of the chain rail 20 overlapped on the outer side of the chain rail 20 through the bushing 21 pressed into the left and right chain rails 20. The pin 22 is fitted into the bushing 21 through a gap, a lubricant 42 such as grease or lubricating oil is added to the gap, and the gap is sealed by the sealing member 43 to seal the lubricant 42.

[0045] Figure 1 2( a ) is an elastic member formed into an annular seal ring and is sandwiched between the end of the bushing 21 and the periphery of the second hole 36 of the chain rail 20 , and in this embodiment, between the bottom surface 39 of the recess 38 .

[0046] The sealing member 43 is embedded and held in the embedding portion 45. The embedding portion 45 is formed at least one of the end of the bushing 21 and the periphery of the second hole portion 36 of the chain rail 20, that is, the bottom surface portion 39 of the recessed portion 38, and the second hole portion 36 is opposite to the end of the bushing 21 with a gap 46 therebetween. For example, the embedding portion 45 is a groove portion formed at least one of the end surface of the bushing 21 and the bottom surface 39 of the recessed portion 38, and the bottom surface 39 is a side surface portion of the periphery of the second hole portion 36 of the chain rail 20. In the example shown, the embedding portion 45 is formed on the end surface of the bushing 21. In addition, the embedding portion 45 is recessed in the edge of the shaft hole of the bushing 21. Therefore, in this embodiment, one end of the sealing member 43 embedded in the embedding portion 45 contacts the end or end surface of the bushing 21, the other end contacts the bottom surface portion 39 of the recessed portion 38, and the inner peripheral portion contacts the outer peripheral surface of the pin 22.

[0047] Furthermore, when the axial load L acts on a part of the crawler 11, the bushing 21 moves laterally together with the link rail 20 due to the axial deformation of the sealing member 43 embedded in the embedding portion 45, and the amount of lateral movement is equivalent to the size of the gap 46, so that as shown in FIG. 2(b), the end or end surface of the bushing 21 can contact with a supporting member different from the sealing member 43, for example, in this embodiment, the bottom surface 39 of the periphery 38 of the second hole portion 36 of the link rail 20.

[0048] Therefore, the sealing member 43 preferably has a cross-sectional shape with a large allowable deformation amount (crush margin). For example, in this embodiment, the sealing member 43 with an O-shaped cross section is used. The sealing member 43 is not limited to this, and may also have a D-shaped or X-shaped cross section.

[0049] In addition, the depth and width of the embedded portion 45 have dimensions sufficient to allow the embedded sealing member 43 to deform. For example, when the depth of the embedded portion 45 is too large, the sealing member 43 cannot properly contact the end or end surface of the bushing 21 and the bottom surface 39 of the recess 38, and the sealing property cannot be maintained. In addition, when the width of the embedded portion 45 is insufficient, the deformation of the sealing member 43 is restricted, and when an axial force is applied to the crawler 11, the sealing member 43 cannot be sufficiently crushed, and the end of the bushing 21 cannot contact the bottom surface 39 of the recess 38. In the present embodiment, the gap 46 is set to, for example, about 0.5 mm. Therefore, the shapes of the sealing member 43 and the embedded portion 45 are set so that the allowable deformation of the sealing member 43 in the axial direction is 0.5 mm or more.

[0050] As described above, in the present embodiment, the embedding portion 45 is formed at least one of the end of the bushing 21 and the periphery of the second hole portion 36 of the chain rail 20 opposite to the end of the bushing 21 with the gap 46 therebetween, so that the end or end surface of the bushing 21 can be supported in the axial direction by a support member harder than the sealing member 43, for example, the periphery of the second hole portion 36 of the chain rail 20, wherein the embedding portion 45 is embedded with the annular sealing member 43 for sealing the lubricant 42 sandwiched between the pin 22 and the bushing 21. Since the chain rail 20 is basically not elastic, in the present embodiment, the contact between the end or end surface of the bushing 21 and the periphery of the second hole portion 36 of the chain rail 20 is an inelastic contact. The support member is not limited thereto, and the support member may also have elasticity as long as it is harder than the sealing member 43 and less likely to deform than the sealing member 43.

[0051] Therefore, when the load L is applied to the link rail device 12 or the crawler belt 11 in the axial direction, the load L does not need to be borne only by the sealing member 43, and therefore, even when the operation such as rotation is performed in this state, the sealing member 43 is not worn, and the size of the sealing member 43 can be reduced while the lubricant 42 is appropriately sealed. Therefore, it is not necessary to form a partially thick mountain-shaped boss portion around the second hole portion 36 of the link rail 20 to hold the sealing member 43, so that the sealing function of the sealing member 43 can be maintained for a long time, and the link rail 20 that is thin and light as a whole can be formed. Therefore, since the link rail 20 can be formed using the rolled material 39 as a base material, the durability and productivity can be improved, and the processing cost can be reduced, and the material cost can be reduced by making the rolled material 39 thinner, so that a low-cost link rail 20 can be provided.

[0052] In addition, for example, by using a sealing member 43 having an O-shaped, D-shaped, or X-shaped cross-section having a larger crush margin than a sealing member 43 having a W-shaped cross-section, even when a load L is applied in the axial direction, the sealing member 43 does not reach the allowable deformation amount and wear before the end of the bushing 21 contacts the periphery of the second hole portion 36 of the chain rail 20.

[0053] Furthermore, since the chain rail 20 has a vertically symmetrical or substantially symmetrical shape except for the bolt hole portion 28 that can be processed later, any one of the left and right chain rails 20 can be processed from the same rolled material 39, so there is no need to prepare a dedicated rolled material for each of the left and right chain rails 20, thereby further reducing costs.

[0054] By setting the embedding portion 45 as a groove portion formed in at least one of the bottom surfaces 39 of the recessed portion 38 on the end surface of the bushing 21 and the periphery of the second hole portion 36 of the chain rail 20, the embedding portion 45 can be easily formed, and by setting the shape of the embedding portion 45 and the allowable deformation amount of the sealing component 43, it is easy to achieve a structure in which the end portion or end surface of the bushing 21 contacts the periphery of the second hole portion 36 of the chain rail 20 through axial deformation of the sealing component 43 embedded in the embedding portion 45.

[0055] Furthermore, the crawler track 11 includes the above-described link rail device 12 and the shoe 13 mounted on each link rail 20 of the link rail device 12, so that a low-cost and highly reliable crawler track 11 capable of maintaining performance for a long time can be provided.

[0056] In addition, in a general chain rail, a mud discharge hole is provided at the center of the chain rail body, and a bolt insertion hole is provided to penetrate the mud discharge hole, and a mounting bolt for fixing the shoe is inserted into the mounting hole provided on the shoe and the bolt insertion hole of the chain rail, and is fastened with a nut at the mud discharge hole portion. However, in a chain rail for a relatively small tracked vehicle, the mud discharge hole can be easily provided by punching or the like due to its thickness, while in a chain rail for a relatively large tracked vehicle, it is difficult to use punching due to its thickness. In the present embodiment, the bolt hole portion 28 is formed in a direction orthogonal to the rotation axis direction of the chain rail 20, and by screwing the mounting bolt 27 inserted from the mounting hole 29 of the shoe 13 to the bolt hole portion 28, the shoe 13 can be easily mounted on the chain rail 20 even in the track 11 of a large tracked vehicle where it is difficult to punch a mud discharge hole on the chain rail 20.

[0057] The following, Figure 8 It should be noted that Figures 1 to 7 The same parts in the illustrated embodiments have the same symbols and will not be described in detail herein.

[0058] In this embodiment, the fitting portion 45 is a groove formed around the second hole 36 of the chain rail 20, that is, the bottom surface 39 of the recess 38. The fitting portion 45 is located radially away from the edge of the shaft hole of the bushing 21 and the edge of the second hole 36.

[0059] As described above, by forming the embedding portion 45 at least at one of the end of the bushing 21 and the periphery of the second hole portion 36 of the chain rail 20 opposite to the end of the bushing 21 with the gap 46 therebetween, and by axial deformation of the sealing component 43 embedded in the embedding portion 45, the end of the bushing 21 can be supported by the periphery of the second hole portion 36 of the chain rail 20, so that the chain rail 20 can be formed at a low cost and the lubricant 42 can be appropriately sealed, wherein the embedding portion 45 is for embedding the annular sealing component 43, and the annular sealing component 43 is used to seal the lubricant 42 sandwiched between the pin 22 and the bushing 21.

[0060] The following, Fig. 9 It should be noted that the same parts as in each embodiment have the same symbols and are not described in detail here.

[0061] In the present embodiment, the fitting portion 45 is a chamfered portion formed at least one of the edge of the hole portion of the bushing 21 and the edge of the second hole portion 36 of the chain rail 20. In the example shown, the fitting portion 45 is mainly formed as a large chamfered portion at the edge of the hole portion of the bushing 21 and a small chamfered portion at the edge of the second hole portion 36 of the chain rail 20, and they are configured into a continuous triangular cross section.

[0062] Therefore, the sealing member 43 contacts the following three positions: the chamfered surface of the edge of the second hole portion 36 of the chain rail 20; any one of the end surface of the bushing 21, the side surface of the periphery of the second hole portion 36 of the chain rail 20 and the chamfered surface of the shaft hole edge of the bushing 21, or the chamfered surface of the edge of the second hole portion 36 of the chain rail 20 and the chamfered surface of the shaft hole edge of the bushing 21; and the outer peripheral surface of the pin 22. In the fitting portion 45, the size of the triangular gap formed by chamfering is set to a size sufficient to allow deformation of the fitting sealing member 43.

[0063] As described above, by forming the embedding portion 45 at least at one of the end of the bushing 21 and the periphery of the second hole portion 36 of the chain rail 20 opposite to the end of the bushing 21 with the gap 46 therebetween, and by axial deformation of the sealing component 43 embedded in the embedding portion 45, the end of the bushing 21 can be supported by the periphery of the second hole portion 36 of the chain rail 20, so that the chain rail 20 can be formed at a low cost and the lubricant 42 can be appropriately sealed, wherein the embedding portion 45 is for embedding the annular sealing component 43, and the annular sealing component 43 is used to seal the lubricant 42 inserted between the pin 22 and the bushing 21.

[0064] In addition, by setting the embedding portion 45 as a chamfered portion formed at at least one of the edge of the hole portion of the bushing 21 and the edge of the second hole portion 36 of the chain rail 20, the embedding portion 45 can be easily formed, and by setting the shape of the embedding portion 45 and the allowable deformation amount of the sealing component 43, it is easy to achieve a structure in which the end or end face of the bushing 21 contacts the periphery of the second hole portion 36 of the chain rail 20 through axial deformation of the sealing component 43 embedded in the embedding portion 45.

[0065] It should be noted that, in addition to the above-mentioned embodiment, the embedded portion 45 can be formed so that the mating sealing component 43 contacts the end of the bushing 21 and the periphery of the second hole portion 36 of the chain rail 20, and the sealing component 43 can be fully deformed in the axial direction so that the end of the bushing 21 can be supported by the periphery of the second hole portion 36 of the chain rail 20 through the axial load L.

[0066] Furthermore, when the sealing member 43 is deformed in the axial direction by the load L, the supporting member for supporting the end of the bushing 21 may not be the chain rail 20, but may be, for example, a washer of another member provided around the second hole portion 36 of the chain rail 20, as long as it is a member harder than the sealing member 43, that is, it is not substantially deformed by the load L. That is, it is not limited to the structure in which the periphery of the second hole portion 36 of the chain rail 20 directly contacts and supports the end of the bushing 21, and the end of the bushing 21 may be indirectly supported by the supporting member around the second hole portion 36 of the chain rail 20. By setting the supporting member to be a member harder than the sealing member 43 and contacting the end of the bushing 21 when the sealing member 43 is deformed in the axial direction by the load L, the same action and effect as in each embodiment can be achieved.

[0067] In addition, the link rail device 12 is formed in a ring shape by sequentially connecting the link rails 20 of the same shape, but is not limited thereto, and may be formed separately with one link rail 20 on which the bushing 21 is mounted and another link rail 20 stacked on the outside of the one link rail 20 and with the pin 22 pressed in. In this case, a plurality of first holes 35 are formed in one link rail 20, and a plurality of second holes 36 are formed in the other link rail 20.

[0068] Also, the shoe 13 and the chain rail 20 may be fastened with nuts by mounting bolts using general mud discharge holes and bolt insertion holes, or may be connected by welding.

[0069] In addition, the chain rail device 12 is suitable for the crawler 11, but can also be applied to devices other than crawlers. For example, it is also possible to construct a conveying device used at a work site by installing a conveying plate or a conveying rod or other bypassing components on the chain rail 20 of the circularly connected chain rail device 12.

[0070] Industrial Applicability

[0071] The present invention can be utilized in industries that manufacture and sell crawler tracks and their links used in crawler-type vehicles such as working machines, for example.

[0072] Description of Reference Numerals

[0073] 11 Tracks

[0074] 12Chain track device

[0075] 13W

[0076] 20 Links

[0077] 21 Bushing

[0078] 22 pins

[0079] 35 First hole portion as hole portion

[0080] 36 Second hole portion as hole portion

[0081] 40Rolled materials

[0082] 42 Lubricant

[0083] 43 Sealing parts

[0084] 45 embedded part

[0085] 46 gaps.

Claims

1. A chain track device, characterized in that: a plurality of chain rails formed of a rolled material and having a plurality of hole portions; a bushing pressed into a hole portion of the chain track; a pin that connects one chain rail to another chain rail by being pressed into a hole portion of the other chain rail via a bushing that is pressed into a hole portion of the one chain rail; and annular sealing member, which is used to seal the lubricant trapped between the pin and the bushing, An embedding portion for embedding a sealing member is formed at at least one of an end portion of the bushing and a periphery of a hole portion of the link rail that faces the end portion of the bushing with a gap therebetween. Due to the axial deformation of the sealing member fitted in the fitting portion, the end of the bushing can be supported by the supporting member that is harder than the sealing member.

2. The chain track device according to claim 1, characterized in that: The fitting portion is a groove portion formed in at least one of the end surface of the bushing and the side surface portion around the hole portion of the link rail.

3. The chain track device according to claim 1, characterized in that: The fitting portion is a chamfered portion formed at least one of an edge of the hole portion of the bushing and an edge of the hole portion of the link rail.

4. A crawler, characterized in that: include: The chain track device according to any one of claims 1 to 3, wherein a plurality of chain tracks are connected in an annular manner by bushings and pins; and The shoe is installed on each chain rail of the chain rail device.

Images