JP2010064595A - Lower traveling body of crawler type vehicle - Google Patents

Abstract

A lower part of a crawler-type vehicle that enables a translifter device to be reduced in weight and cost despite the use of a connection structure that uses a connection link that has excellent connection accuracy and facilitates crawler width expansion / contraction. Provide a running body.
A base end side of a connecting link 7 of a connecting device 4 is connected to a mounting bracket 6 provided on a track frame 1, and a tip is inserted into a link opening provided on a crawler frame. When the outer end surface 5ao of the expansion / contraction bracket 5 comes into contact with the distal end stopper 7b, the upper and lower pin holes 5b and 5d are aligned, and the expansion pin hole 7c that holds the crawler width expansion position is formed. On the other hand, a base end stopper 7e is provided, and when the inner end surface 5ai of the expansion / contraction bracket 5 abuts on the base end stopper 7e, the upper and lower pin holes 5b and 5d are matched to reduce the crawler width reduction position. A pin hole 7d is provided.
[Selection] Figure 4

Description

  The present invention relates to a lower traveling body of a crawler type vehicle configured such that an interval between left and right crawlers (hereinafter referred to as a crawler width) can be expanded and reduced.

  In a crawler type vehicle such as a crawler crane or a hydraulic excavator, a configuration is known in which the crawler width is expanded in order to increase stability during work, and the crawler width can be reduced based on legal restrictions during transportation by a trailer. . In a crawler type vehicle that adopts such a crawler width expansion / contraction type, both crawler frames to which the crawler is attached are attached to the track frame so as to be movable between the crawler width expansion position and the crawler width reduction position. The structure which connects with respect to a track frame in the position is taken.

As a connection structure for connecting the track frame and the side frame using a connection link, for example, a structure having a configuration described later is known. Hereinafter, the connection structure according to Conventional Example 1 will be described with reference to the accompanying drawings. 6 is a partially sectional plan view of the crawler width expanded state, FIG. 7 is a partially sectional plan view of the crawler width reduced state, FIG. 8A is an enlarged plan view of the frame connecting portion in the crawler width expanded state, and FIG. FIG. 8B is a view on arrow D in FIG. Incidentally, FIG. 1 in W ₁ is extended during crawler width, 2 in W ₂ is reduced when the crawler width. Further, since the connection structure according to the conventional example 1 is the same structure on the left and right, only the left connection structure in FIGS. 6 and 7 is shown in FIGS.

  6 and 7, reference numeral 51 denotes a track frame, and reference numeral 52 denotes left and right side frames to which the crawler 53 is mounted (hereinafter referred to as a crawler frame). Axles 51a projecting in opposite directions are provided on the left and right sides of the track frame 51, and an axle insertion hole 52a is provided in the crawler frame 52. The axle 51a is slidably inserted into the axle insertion hole 52a. Thus, the crawler frame 52 is attached to the track frame 51 so as to be movable between the crawler width expansion position (FIG. 6) and the crawler width reduction position (FIG. 7). A connecting link 54 is attached to each of the left and right crawler frames 52 inward by brackets 52b and pins 52c, and the connecting link 54 is attached to a link connecting member 55 fixed to the track frame 51 at both the crawler width expansion and contraction positions. The crawler frame 52 is fixed to the left and right sides of the track frame 51 by being connected by the connecting pins 56.

Next, the details of the connecting structure will be described with reference to FIGS. 8 (a) and 8 (b) sequentially. The connecting link 54 is provided with an expansion position pin hole 54b at the distal end and a reduction position pin hole 54c at the base end on the side frame 52 side. The upper surface 54a between the pin holes 54b and 54c of the connection link 54 is a pin support surface (hereinafter referred to as the upper surface 54a) for supporting the connection pin 56 from below and holding it upright during the crawler width expansion / contraction operation. Is referred to as a pin support surface 54a). Further, an expansion stopper 54d is provided on the upper surface of the distal end portion of the connecting link 54, and a reduction stopper 54e is provided on the upper surface of the proximal end portion. That is, the expansion stopper 54d contacts the link connecting member 55 when the crawler width is expanded, and the expansion stopper 54e contacts the link connecting member 55 when the crawler width is reduced, thereby preventing further movement of the crawler frame 52.
The link connecting member 55 includes an upper plate 55a that contacts the stopper 54d at the time of expansion and the stopper 54e at the time of reduction, and a lower plate 55b parallel to the upper plate 55a. The connecting link 54 is inserted.

  The link connecting member 55 includes first pin holes (hereinafter referred to as upper first pin holes and lower first pin holes) 55c and 55d and second pin holes (hereinafter referred to as “lower pin holes”) on both the upper plate 55a and the lower plate 55b. 55e and 55f (which are referred to as upper second pin hole and lower second pin hole) are provided at right and left intervals, and when the crawler width is expanded, the first pin holes 55c and 55d serve as the expansion position pin holes 54b of the connecting link 54. When the crawler width is reduced, the second pin holes 55e and 55f are respectively matched with the reduction position pin holes 54c of the connecting link 54. The link connecting member 55 has a short tubular pin holding cylinder (hereinafter referred to as a first pin holding cylinder or a second pin holding pipe) at a position corresponding to the first and second pin holes 55c and 55e on the upper surface of the upper plate 55a. 55g and 55h (referred to as cylinders) are fixed vertically (for example, see Patent Document 1).

  Next, as a connection structure for connecting the track frame and the side frame without using a connection link, for example, a structure having a configuration described later is known. Hereinafter, the connection structure according to Conventional Example 2 will be described with reference to the accompanying drawings. 10 is a plan view of the rear portion of the lower traveling body of the crawler type work machine, FIG. 11 is a plan view showing a coupling structure of the right crawler frame and the axle of the track frame, and FIG. 12 is taken along line EE in FIG. It is sectional drawing.

  That is, the crawler frame 102 is provided with a protruding portion 122 that protrudes from the inner side surface. A connecting plate 131 that protrudes further inward along the upper surface of the axle 113 is fixed to the tip of the top plate portion 122a of the protruding portion 122. The connecting plate 131 is provided with a crawler side pin hole 132. Further, an expansion position pin hole 133 and a reduction position pin hole 134 are provided on the upper surface of the axle 113, and when the crawler frame 102 is in the expansion position, the crawler side pin hole 132 and the expansion position pin hole are provided. When the crawler frame 102 is in the contracted position, the crawler side pin hole 132 and the contracted position pin hole 134 are aligned. The fastening pins 135 are configured to be inserted into these holes. Reference numeral 115 shown in FIG. 10 is an arm member for supporting a translifter (not shown), and reference numeral 123 is an expansion / contraction hydraulic cylinder that moves the track frame 102 between an expansion position and a reduction position. is there.

Further, a pin insertion portion 136 made of a pipe member or the like is provided at the tip of the rear side plate portion 122b of the protrusion 122, and a positioning pin 137 protruding to the inner space side of the protrusion 122 is removed from the pin insertion portion 136. It is provided as possible. On the other hand, on the rear side surface of the axle 113, there is a rectangular flat pad plate 138 for filling a gap between the side wall surface 121b of the through hole 121 of the crawler frame 102 and the inner surface of the rear side plate portion 122b of the protruding portion 122. It is fixed. As shown in FIG. 11, the pad plate 138 is provided with a notch groove 139 extending from one end in the longitudinal direction to the center along the center line. The notch groove 139 tracks the crawler frame 102. This is to avoid interference with the positioning pin 137 when moving between the expansion position and the contraction position of the axle 113 of the frame 101. The crawler frame 102 is moved to the expansion position of the axle 113 of the track frame 101. In this case, the positioning pin 137 comes into contact with the bottom of the notch groove 139 so that the pad plate 138 functions as an expansion position stopper (see, for example, Patent Document 2).
No. 7-15828 JP 2006-290020 A

  In the connection configuration according to the conventional example 1, when the crawler frame 52 in the crawler width expansion state is reduced, when the reduction stopper 54e of the connection link 54 contacts the link connection member 55, the reduction position pin hole 54c is second. The connecting pin 56 that matches the pin holes 55e and 55f and is vertically supported by the pin holding cylinder 55h naturally falls, and the crawler frame 52 is fixed to the track frame 51 at the crawler width reduction position. Further, when the crawler frame 52 in the crawler width reduced state is expanded, the expansion position pin hole 54b matches the first pin holes 55c and 55d when the expansion stopper 54d of the connection link 54 comes into contact with the link connection member 55. Then, the connecting pin 56 vertically supported by the pin holding cylinder 55g naturally falls, and the crawler frame 52 is fixed to the track frame 51 at the crawler width expansion position.

However, depending on the crawler width expansion / contraction dimension of the lower traveling pair, generally, in the crawler width reduction state, as shown in FIG. Since the leading ends of the links 54 overlap each other, and a space cannot be secured between the leading ends of the left and right connecting links 54, the left and right connecting links 54 are disposed at positions shifted vertically. Therefore, the state of the translifter arm 62 that mounts the translifter 61 of the translifter device 60 for lifting the crawler type vehicle on the track frame 51 when performing the crawler width expansion / contraction operation is as shown in the conventional translifter device mounting state explanatory diagram. As shown in FIG. 9B, there is a restriction on the height dimension of the base end side mounting portion of the transformer lifter arm 62, and in order to ensure the section modulus of the transformer lifter arm 62, the plate thickness of the constituent plate material is increased. In addition to the necessity, since it is necessary to increase the thickness of the arm mounting pin 63 that supports the transformer lifter arm 62 so as to be rotatable around the vertical axis, the transformer lifter device 60 is heavy and expensive. .

  In addition, in the connection configuration according to the above-described conventional example 2, a protrusion is simply formed at the peripheral edge of the through-hole of each crawler frame, and a coupling plate having a crawler-side pin hole is provided at the tip of the protrusion to protrude the axle. An extension position pin hole and a reduction position pin hole are provided, and a rectangular plate-like pad plate 138 for closing a gap with the inner surface of the rear side plate portion of the protrusion 122 is fixed to the rear side surface of the axle 113. ing.

However, there is a gap of several mm between the pad plate and the through hole, and the crawler side pin hole and the expansion position pin hole do not match the diameter centers of the crawler side pin hole and the reduction position pin hole. Problems as described later arise.
(1) The inner diameter of the crawler side pin hole, the expansion position pin hole, and the reduction position pin hole is made larger than the outer diameter of the fastening pin to increase the backlash, or the fastening pin is moved with a strong pressing force by a hydraulic device or the like. It is necessary to push into the crawler side pin holes and the expansion position pin holes, between the crawler side pin holes and the reduction position pin holes, and to remove them from these pin holes. In other words, the connection accuracy is inferior to the connection structure using the connection link, and the crawler width expansion / contraction work is extremely difficult.
(2) Since the fastening pin must be in a cantilever configuration, it is necessary to increase the diameter of the fastening pin.
(3) An expansion position pin hole and a reduction position pin hole are provided on the upper surface of the axle, and high stress is generated at the edge of these pin holes.

  Therefore, an object of the present invention is to make it possible to reduce the weight and cost of the translifter device despite the adoption of a connection structure using a connection link that has excellent connection accuracy and that facilitates crawler width expansion / contraction. It is to provide a lower traveling body of a crawler type vehicle.

  In order to solve the above problems, the means adopted by the lower traveling body of the crawler type vehicle according to claim 1 of the present invention is that the crawler frame in which the crawler is mounted on the outer periphery of each of the left and right axles of the track frame, The crawler width expansion position where the distance between the left and right crawlers is maximum and the crawler width reduction position where the distance between the crawler width is minimum are provided so as to be laterally movable, and before and after the track frame, the track frame and the left and right crawler frames In a lower traveling body of a crawler type vehicle provided with a pair of detachable translifter devices, and a pair of connecting devices for connecting the crawler width expansion position and the crawler width reduction position. The lower traveling body is line-symmetric with respect to a vertical line passing through the center in the left-right direction. An expansion / contraction bracket provided on the crawler frame, a mounting bracket provided closer to the expansion / contraction bracket than the center in the width direction of the track frame, and a base end of the mounting bracket; The end stopper is connected to the outer end face of the expansion / contraction bracket on the front end side, and when the end stopper comes into contact with the outer end face, it matches the pin hole, and the crawler frame is crawled by inserting the connecting pin. A base end stopper that has an expansion pin hole connected to the width expansion position and that is on the base end side and closer to the front end side than the mounting bracket, and the inner end surface of the expansion / contraction bracket contacts the inner end surface of the base end stopper When the end face comes into contact with the pin hole, the crawler frame is reduced by the insertion of the connecting pin. Is characterized in that a connecting link having a reduced pin holes for connecting the position.

  In the lower traveling body of the crawler type vehicle according to the first aspect of the present invention, the base end side of each of the connecting links of the pair of connecting devices is connected to the mounting bracket provided on the expansion / contraction bracket side rather than the center in the width direction of the track frame. Has been. Therefore, according to the connecting device according to claim 1 of the present invention, a space is formed between the mounting brackets to which the proximal ends of the connecting links of the pair of left and right connecting devices are connected.

  Further, in the lower traveling body of the crawler type vehicle according to claim 1 of the present invention, the connecting link of each of the pair of left and right connecting devices has a front end stopper that contacts the outer end surface of the expansion / contraction bracket on the front end side, and the front end stopper An expansion pin for connecting the crawler frame to the crawler width expansion position by fitting the connection pin into the crawler width expansion position when the connection pin of the expansion / contraction bracket provided on the crawler frame contacts the outer end surface. It has a hole. Further, on the proximal end side and on the distal end side with respect to the mounting bracket, the proximal end stopper with which the inner end surface of the expansion / contraction bracket abuts, and when the inner end surface abuts against the proximal end stopper, the pin hole matches with the pin hole, A reduction pin hole is provided for connecting the crawler frame to the crawler width reduction position by inserting a connection pin. Therefore, according to the lower traveling body of the crawler type vehicle according to the first aspect of the present invention, when the outer end surface of the expansion / contraction bracket comes into contact with the distal end stopper on the distal end side of the coupling link of each of the pair of coupling devices, The expansion pin hole and the expansion / contraction bracket pin hole match. Further, when the inner end surface of the expansion / contraction bracket contacts the base end stopper on the base end side of the connection link, the reduction pin hole of the connection link and the pin hole of the expansion / contraction bracket coincide.

  The means adopted by the lower traveling body of the crawler type vehicle according to the second aspect of the present invention is the lower traveling body of the crawler type vehicle according to the first aspect, wherein the connecting link is operated by the crawler frame when the crawler width is reduced. A link opening in which the front end side is loosely fitted is provided.

In the lower traveling body of the crawler type vehicle according to the second aspect of the present invention, the crawler frame is provided with a link opening in which the distal end side of the connecting link is loosely fitted when the crawler width is reduced.
Therefore, according to the lower traveling body of the roller vehicle according to claim 2 of the present invention, in the crawler width reduced state, the distal end side of the connecting link of the connecting device protrudes into the link opening and is positioned in the crawler frame. is doing.

  According to the lower traveling body of the crawler type vehicle according to the first aspect of the present invention, the base end side of the connecting link of each of the pair of left and right connecting devices is provided closer to the expansion / contraction bracket side than the center in the width direction of the track frame. It is connected to the bracket. Therefore, a space is formed between the mounting brackets to which the base end sides of the connection links of the pair of left and right connecting devices are connected, and there is no restriction on the height dimension of the base end side mounting portion of the transformer lifter arm. The weight of the translifter device can be reduced, and the cost of the translifter device can be reduced.

  According to the lower traveling body of the crawler type vehicle according to the first aspect of the present invention, when the outer end surface of the expansion / contraction bracket comes into contact with the distal end stopper on the distal end side of the coupling link of each of the pair of left and right coupling devices, the coupling link Since the expansion pin hole matches the pin hole of the expansion / contraction bracket, the connection pin can be easily inserted into these holes. In addition, when the inner end face of the expansion / contraction bracket comes into contact with the base end stopper on the base end side of each connection link, the reduction pin hole of the connection link and the pin hole of the expansion / contraction bracket match, so these holes can be easily A connecting pin can be inserted into the. Accordingly, it is not necessary to make the inner diameters of the expansion pin hole and the reduction pin hole provided in the connection link larger than the outer diameter of the connection pin as in the conventional example 2, so that the same as in the conventional example 1 In addition, the connection accuracy is excellent, and the crawler width expansion / contraction work can be performed very easily and in a short time.

  According to the lower traveling body of the crawler type vehicle according to the second aspect of the present invention, in the crawler width reduced state, the distal end side of each of the connecting links of the pair of left and right connecting devices is free to the link opening provided in the crawler frame. Plunge in the fitted state. Therefore, since a space can always be secured between the mounting brackets that connect the base end sides of the connecting links of the pair of left and right connecting devices, it is not necessary to shift their arrangement positions up and down.

Hereinafter, a lower traveling body of a crawler type vehicle according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a plan view showing a crawler width expanded state of a lower traveling body of a crawler type vehicle. FIG. 2 is a partially cutaway plan view of the rear side of the lower traveling body of the crawler type vehicle, in which the left side in the figure shows the crawler width reduced state and the right side in the figure shows the crawler width expanded state. FIG. 3 is a view as seen from the direction of arrow A in FIG. FIG. 4A is an enlarged plan view of the connecting device on the left side in the crawler width expanded state, and FIG. 4B is a view taken in the direction of arrow B in FIG. FIG. 5A is an enlarged plan view of the connecting device on the left side in the crawler width reduction state, and FIG. 5B is a view as seen from the direction C of FIG. Incidentally, _{W 1} shown in FIG. 1, 2 and 3 show an extended time crawler width, _{W 2} shown in FIG. 2 and 3 show a reduced time crawler width. The pair of connecting devices are symmetrical with respect to a vertical line passing through the center in the left-right direction of the lower traveling body, and have the same structure on the left and right.

Reference numeral 1 shown in the figure is a track frame, and reference numeral 2 is a left and right crawler frame on which a crawler 3 is mounted. The track frame 1 and the left and right crawler frames 2 constitute a lower traveling body 10 of a crawler type vehicle. Axles 1a projecting in opposite directions are provided on the left and right sides of the track frame 1 of the lower traveling body 10. The crawler frame 2 of the lower traveling body 10 is provided with an axle insertion hole 2a, and the axle 1a is slidably inserted into the axle insertion hole 2a. Such a fitting structure, the relative crawler frame 2 is the track frame 1, and the crawler width expanded position the outer dimension is time crawler width W ₁ the largest extension of the left and right crawlers 3, outside of the left and right crawlers 3 dimension is movable between the crawler width retracted position that minimizes the reduction time of the crawler width W _2.

  The left and right crawler frames 2 and 2 are connected to the track frame 1 at the base end side, and are provided with a connecting link 7 having a free end at the front end side on the crawler frame 2 side. The apparatus 4 is configured to be fixed at the crawler width expansion position and the crawler width reduction position. As shown in FIG. 1, the expansion operation of the left and right crawler frames 2, 2 is performed by expanding / contracting the expansion / contraction rod of the hydraulic cylinder 11 for expanding / contracting the left / right pair of crawlers disposed near the middle of the track frame 1. It is configured to be performed by operation.

  Next, details of the structure of the connecting device will be described with reference to FIGS. 3, 4 (a), (b) and FIGS. 5 (a), (b). That is, the connecting device 4 includes an expansion / contraction bracket 5, which will be described later, for connecting the left and right crawler frames 2, 2 and the track frame 1, a mounting bracket 6, a connecting link 7, and a connecting pin 8. .

  The expansion / contraction bracket 5 constitutes an axle insertion hole of the crawler frame 2 and is fixed to a protruding side plate portion 2b protruding in the center direction of the lower traveling body. The expansion / contraction bracket 5 includes an upper plate 5a, and a lower lower plate 5c that is parallel to the upper plate 5a and that is spaced from the upper plate 5a by a distance at which the distal end side of the connecting link 7 can be inserted. It has become. The connecting link 7 interposed between the upper plate 5a and the lower plate 5c is fixed to the upper plate 5a and the lower plate 5c, so that the crawler frame 2 is positioned at the crawler width expansion position and the crawler width with respect to the track frame 1. An upper pin hole 5b and a lower pin hole 5d into which the connecting pin 8 held at the reduced position is removably inserted are formed. In addition, what is planted on the upper surface of the lower plate 5c and is in contact with the outer side of the connecting link 7 prevents the connecting link 7 from being detached from the expansion / contraction bracket 5 when the connecting pin 8 is pulled out. This is a link disconnection prevention pin 5e.

  The mounting bracket 6 is fixed to the rear side plate portion of the track frame 1 and closer to the expansion / contraction bracket 5 side than the center of the track frame 1 in the width direction. The mounting bracket 6 includes an upper plate 6a, and a lower lower plate 6c that is parallel to the upper plate 6a and that is spaced from the upper plate 6a by a distance at which the base end side of the connecting link 7 can be inserted. It is made up of. The upper plate 6a is provided with an upper mounting pin hole 6b, and the lower plate 6c is provided with a lower mounting pin hole 6d. The upper mounting pin hole 6b and the lower mounting pin hole 6d are inserted into the upper plate 6a. The base end side of the connecting link 7 is connected by the mounting pin 6e.

  The connection link 7 includes a long flat plate-like link body 7a formed of a flat plate. A tip stopper 7b that contacts the outer end surface 5ao of the upper plate 5a of the expansion / contraction bracket 5 is provided on the tip end side (left side in FIGS. 4 and 5) of the link body 7a, and the tip stopper 7b is provided on the outer end surface. An expansion pin hole that fits into the upper pin hole 5b and the lower pin hole 5d of the expansion / contraction bracket 5 when connected to 5ao and connects the crawler frame 2 to the crawler width expansion position by the insertion of the connection pin 8. 7c is provided.

  Further, the base end side of the link main body 7a (the right side in FIGS. 4 and 5) and the inner end face 5ai of the upper plate 5a of the expansion / contraction bracket 5 is in contact with the front end side of the mounting bracket 6. A stopper 7e is provided, and when the inner end surface 5ai comes into contact with the base end stopper 7e, it matches the upper pin hole 5b and the lower pin hole 5d of the expansion / contraction bracket 5, and the insertion of the connecting pin 8 causes the A reduction pin hole 7d for connecting the crawler frame 2 to the crawler width reduction position is provided. When the crawler frame 2 is held at the crawler width reduction position, the distal end side of the link main body 7a of the connecting link 7 is in a link opening 2c (see FIG. 3) provided in the crawler frame 2. It rushes in a loose fit state. Reference numeral 7f denotes a mounting pin hole, and the base end side of the connecting link 7 is connected to the mounting bracket 6 by inserting the mounting pin 6e into the mounting pin hole 7f.

  2 and 3, the trans-lifter device 9 includes a hydraulic cylinder having a telescopic rod that extends and contracts downward, and a grounding plate member (not shown) that is loosely connected to the lower end of the telescopic rod. It has. The head side of the hydraulic cylinder of the transformer lifter 9a is fixed to one end of the transformer lifter arm 9b, and a side attachment portion formed by branching at the base end side of the transformer lifter arm 9b, that is, an upper attachment portion. 9bu and a lower mounting portion 9bd project from the track frame 2 and are attached to the upper arm mounting bracket 1b and the lower arm mounting bracket 1c projecting rearward via arm mounting pins 9c that are detachable. . That is, the transformer lifter device 9 is configured to be able to turn about the vertical axis of the arm mounting pin 9c as a turning center.

Hereinafter, the operation mode of the lower traveling body 10 of the crawler type vehicle according to the embodiment of the present invention will be described. In other words, according to the lower traveling body 10 of the crawler type vehicle according to the embodiment of the present invention, the base end side of the connection link 7 of each of the pair of left and right connection devices 4 is larger than the center in the width direction of the track frame 1. It is connected to a mounting bracket 6 provided on the 5 side. Therefore, a space is formed between the mounting brackets 6 to which the base ends of the connecting links 7 of the pair of left and right connecting devices 4 are connected. Therefore, as in the case of the conventional example 2, there is no restriction on the height of the upper mounting portion 9bu and the lower mounting portion 9bd of the transformer lifter arm 9b, so that the weight of the transformer lifter device 9 can be reduced. And the transformer lifter device 9 can be made inexpensive.

Moreover, according to the lower traveling body 10 of the crawler type vehicle according to the embodiment of the present invention, in the crawler width reduced state, as described above, the distal end side of the connection link 7 of each of the pair of left and right connection devices 4 is the crawler frame 2. It rushes into the link opening 2c provided in the state of loose fit.
Therefore, since a space can always be secured between the mounting brackets 6 that connect the base end sides of the connecting links 7 of the pair of left and right connecting devices 4, it is not necessary to shift their arrangement positions up and down.

  Furthermore, according to the lower traveling body 10 of the crawler type vehicle according to the embodiment of the present invention, when the crawler frame 2 in the crawler width reduction position is set to the crawler width expansion position, the outward direction of the expansion / contraction bracket 5 by the expansion / contraction cylinder. When the outer end surface 5ao of the upper plate 5a of the expansion / contraction bracket 5 comes into contact with the distal end stopper 7b on the distal end side of the connection link 7 of each of the pair of right and left connection devices 4 by the movement to the expansion pin hole of the connection link 7 Since 7c matches the upper pin hole 5b of the upper plate 5a of the expansion / contraction bracket 5 and the lower pin hole 5d of the lower plate 5c, the connecting pin 8 can be easily inserted into these holes.

  Further, when the crawler frame 2 at the crawler width expansion position is set to the crawler width reduction position, the expansion / contraction cylinder 5 moves inwardly to the base end stopper 7e on the base end side of the connection link 7 by the expansion / contraction cylinder. When the outer end surface 5ai of the upper plate 5a of the bracket 5 contacts, the reduction pin hole 7d of the connecting link 7 matches the upper pin hole 5b of the upper plate 5a of the expansion / contraction bracket 5 and the lower pin hole 5d of the lower plate 5c. Therefore, the connecting pin 8 can be easily inserted into these holes. Therefore, it is not necessary to make the inner diameters of the expansion pin hole 7c and the reduction pin hole 7d provided in the connection link 7 larger than the outer diameter of the connection pin 8 as in the conventional example 2. Similar to Conventional Example 1, the connection accuracy is excellent, and the crawler width expansion / contraction operation can be performed very easily and in a short time.

In the above embodiment, each of the upper plate 5a and the lower plate 5c of the expansion / contraction bracket 5 that moves to the left and right during the crawler width expansion / contraction operation has one pin hole (upper pin hole, lower pin hole). ) Is provided. However, as in the case of the conventional example 1, two pin holes are provided, a pin holding cylinder for holding the connecting pin 8 in an upright state is provided on the upper surface of the upper plate 5a, and the upper surface of the connecting link 7 is provided. Can be the pin support surface.
Further, the above embodiment is only one specific example of the present invention, and is not limited to the configuration according to the above embodiment, and a design change within a range not departing from the technical idea of the present invention. Is free.

It is a top view which shows the crawler width expansion state of the lower traveling body of a crawler type vehicle concerning embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cutaway plan view of a rear portion of a lower traveling body of a crawler type vehicle according to an embodiment of the present invention, in which a left side in the figure shows a crawler width reduced state and a right side in the figure shows a crawler width expanded state. FIG. FIG. 3 is a view taken from the direction of the arrow A in FIG. 2 and is a view of the lower traveling body of the crawler type vehicle as viewed from the rear side. FIG. 4A is an enlarged plan view of the left connecting device in the crawler width expanded state, and FIG. 4B is a view as viewed from the arrow B in FIG. 4A according to the embodiment of the present invention. FIG. 5A is an enlarged plan view of the left connecting device in the crawler width reduced state, and FIG. 5B is a view as seen from the direction of arrow C in FIG. 5A according to the embodiment of the present invention. FIG. 10 is a partial cross-sectional plan view of the conventional example 1 in a crawler width expanded state. FIG. 10 is a partial cross-sectional plan view of the prior art 1 in a crawler width reduced state. FIG. 8A is an enlarged plan view of the frame connecting portion in the crawler width expanded state, and FIG. 8B is a view taken along arrow D in FIG. FIG. 9 (a) relates to a conventional example, and is an explanatory diagram of an overlapping state on the leading end side of a connecting link, and FIG. It is a top view of the rear part of the lower traveling body of a crawler type work machine according to Conventional Example 2. FIG. 10 is a plan view showing a coupling structure of a crawler frame on the right side and an axle of a track frame according to Conventional Example 2; It is sectional drawing in the EE line | wire of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Track frame, 1a ... Axle, 1b ... Upper arm mounting bracket, 1c ... Lower arm mounting bracket 2 ... Crawler frame, 2a ... Axle insertion hole, 2b ... Projection side plate part, 2c ... Link opening 3 ... Crawler 4 ... Connection Equipment (5, 6, 7, 8)
DESCRIPTION OF SYMBOLS 5 ... Expansion / contraction bracket, 5a ... Upper plate, 5ao ... Outer end surface, 5ai ... Inner end surface, 5b ... Upper pin hole, 5c ... Lower plate, 5d ... Lower pin hole, 5e ... Link disconnection prevention pin 6 ... Mounting bracket, 6a ... Upper plate, 6b ... Upper mounting pin hole, 6c ... Lower plate, 6d ... Lower mounting pin hole, 6e ... Mounting pin 7 ... Connecting link, 7a ... Link body, 7b ... Tip stopper, 7c ... Expansion pin hole, 7d ... Reduction pin hole, 7e ... Base end stopper, 7f ... Mounting pin hole 8 ... Connection pin 9 ... Translifter device, 9a ... Translifter, 9b ... Translifter arm, 9bu ... Upper mounting portion, 9bd ... Lower mounting portion, 9c ... Arm mounting pin 10 ... Lower traveling body 11 ... Hydraulic cylinder (for crawler expansion / contraction)

Claims (2)

  The crawler frame with crawlers attached to the outer periphery of the left and right axles of the track frame can move left and right between the crawler width expansion position where the distance between the left and right crawlers is maximum and the crawler width reduction position where it is minimum. And a connecting device that connects the track frame and the left and right crawler frames at the crawler width expansion position and the crawler width reduction position, and a detachable translifter device, respectively, before and after the track frame. In the lower traveling body of the crawler type vehicle provided in pairs, the pair of connecting devices are line symmetric with respect to a vertical line passing through the center in the left-right direction of the lower traveling body, and each connecting device is connected An expansion / contraction bracket provided on the crawler frame having a pin hole into which the pin is inserted and removed, and the track frame. A mounting bracket provided closer to the expansion / contraction bracket than the center in the width direction of the system, a distal end stopper connected to the outer end surface of the expansion / contraction bracket on the distal end side, and a distal end stopper connected to the mounting bracket on the proximal end side Has a pin hole for expansion that fits the pin hole when it comes into contact with the outer end surface, and connects the crawler frame to the crawler width expansion position by fitting and insertion of the connecting pin. More proximally, the base end stopper with which the inner end face of the expansion / contraction bracket abuts, and the inner end face abuts against the base end stopper, the pin hole is matched, and the crawler frame is inserted by inserting the connecting pin. A lower part of a crawler type vehicle comprising a connecting link having a pinhole for reduction connected to a crawler width reduction position Gyotai.   2. The lower traveling body of the crawler type vehicle according to claim 1, wherein the crawler frame is provided with a link opening in which a distal end side of the connection link is loosely fitted in a crawler width reduction operation.

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