JP7338447B2 - Pin coupling device and construction machinery - Google Patents

Description

TECHNICAL FIELD The present invention relates to a pin connecting device for connecting two members and technology related thereto.

Conventionally, in the field of construction machinery, a technique has been proposed in which a pin is inserted into and removed from a pin hole by a hydraulic cylinder. For example, Patent Literature 1 discloses a pin connecting device (40) including a first pin (41) connecting brackets (15, 16) and a second pin (42) connecting brackets (17, 18). It is

Specifically, in the pin connecting device (40), both pins (41, 42) are stroked in opposite directions to be inserted into and removed from both pin holes (19, 20).

Further, as shown in FIG. 1 of Patent Document 1, the hydraulic cylinder (43) includes a cylinder tube (44), a piston (45), and a hollow piston rod (46) connected to the piston (45). and is expanded and contracted by the action of supplying and discharging oil from the outside, and stroke-drives the pins (41, 42) between the insertion and withdrawal positions.

JP-A-2006-52593

In Patent Literature 1 described above, the cylinder tube (44) has an outer diameter dimension of the main body portion set smaller than the inner diameter dimension of the pin, and a head cover (44a) provided at the end on the head side in a state of being inserted inside the pin. ) is fixed to the opening edges of the pins (41, 42) on the tip side by a plurality of bolts (44c). That is, in Patent Document 1, a configuration is adopted in which a connecting pin and a cylinder head for expanding and contracting the connecting pin are fixed with a plurality of bolts.

By the way, the connecting pin described above may rotate due to backlash. In Patent Document 1, since the connecting pin and the cylinder head of the hydraulic cylinder are fixed, when the connecting pin rotates due to rattling, the cylinder head of the hydraulic cylinder fixed to the connecting pin also follows the connecting pin. Rotate. Unintentional rotation of the cylinder head of the hydraulic cylinder may damage the sealing member provided inside the cylinder head.

Therefore, the present invention provides a pin connecting device that connects two members by extending and contracting a connecting pin using a hydraulic cylinder, and provides a technique in which the rotation of the connecting pin due to rattling does not act on the cylinder head of the hydraulic cylinder. aim.

In order to achieve the above object, the present invention provides a pin connecting device for connecting two members, comprising a hydraulic cylinder including a cylinder rod and a cylinder head, and a cylindrical cylinder through which the body of the cylinder head can be inserted. a pipe, a cylindrical connecting pin having a U-shaped cross-section through which the pipe can be inserted inside and inserted into pin holes respectively formed in the two members to connect the two members; a pressing plate fixed to the contraction-side end portion and extending radially toward the center of the connecting pin to face the contraction-side end portion of the pipe; has a flange that extends radially outward of the cylinder head and faces the extension side end of the pipe, and when the hydraulic cylinder is extended, the extension side end of the cylinder head extends to the inner wall of the connecting pin. while a gap is formed between the flange and the extension side end of the pipe, and the flange abuts the extension side end of the pipe when the hydraulic cylinder is contracted. A pin connection device is provided.

Here, it is preferable that a concave portion is formed in part of the inner wall with which the extension side end portion of the cylinder head abuts.

Further, the presser plate has a protrusion part of the outer edge of which extends outward in the radial direction of the connecting pin, and the protrusion is provided with a fixing member for preventing rotation of the presser plate. preferably.

The present invention also provides a construction machine comprising a first member having a first pin hole, a second member having a second pin hole and being connectable to the first member, a cylinder rod and a cylinder. A hydraulic cylinder that includes a head and is arranged so that the cylinder head extends from the machine center side to the machine side side, a cylindrical pipe that can be inserted through the body of the cylinder head, and the pipe that extends inside. a cylindrical connecting pin having a U-shaped cross section that can be inserted through the first pin hole and the second pin hole to connect the first member and the second member; a pressing plate fixed to the contraction side end of the pin, extending radially toward the center of the connecting pin and facing the contraction side end of the pipe; is provided with a flange that extends outward in the radial direction and faces the extension side end of the pipe, and when the hydraulic cylinder is extended, the extension side end of the cylinder head contacts the inner wall of the connecting pin. a gap is formed between the flange and the extension side end of the pipe, and the flange abuts the extension side end of the pipe when the hydraulic cylinder is contracted. further provides.

According to the present invention, by providing a pipe between the pin and the cylinder head, it is possible to extend and retract the pin without fixing the pin and the cylinder head, and the rotation of the pin due to rattling causes the cylinder head to move. doesn't work.

1 is a side view showing a hydraulic excavator according to an embodiment of the present invention; FIG. The side view which shows a part of upper frame. The side view which shows a sub-frame (adapter). FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3; The figure which shows the time of extension of a hydraulic cylinder (the most extended state of a connection pin). The figure which shows the time of contraction of a hydraulic cylinder (state immediately after a connecting pin starts contraction from a fully extended state). FIG. 5 is a cross-sectional view taken along line VII-VII in FIG. 4; The figure for demonstrating the connecting pin which concerns on a modification.

<1. embodiment>
A pin coupling device and construction machine according to embodiments of the present invention will now be described with reference to FIGS. Below, the hydraulic excavator 1 shown in FIG. 1 is illustrated as an example of the construction machine, and the pin coupling device 6 (6L, 6R) shown in FIG. 4 is illustrated as an example of the pin coupling device.

As shown in FIG. 1, the hydraulic excavator 1 includes a lower running body 2, an upper revolving body 3, a work attachment 4, and the like.

The upper revolving body 3 has an upper frame 30 shown in FIG. The work attachment 4 is attached to the upper frame 30 via the subframe 5 shown in FIG.

The subframe 5 is an adapter for disassembling and assembling a boom and a boom cylinder (not shown) that constitute the work attachment 4 in an integrated state.

As shown in FIG. 2 , the upper frame 30 includes a bottom plate 31 and a pair of left and right vertical plates 33 erected from the bottom plate 31 . 2, the vertical plate 33L arranged on the left side of the pair of left and right vertical plates 33 is illustrated, but the vertical plate 33R is arranged on the right side of the vertical plate 33L so as to be bilaterally symmetrical with the vertical plate 33L. exist.

The vertical plate 33L is formed with a pin hole 35 for inserting a later-described connecting pin 9 (see FIG. 4).

As shown in FIGS. 3 and 4, the subframe 5 includes a left side plate 51L and a right side plate 51R. Since the left side plate 51L and the right side plate 51R are symmetrical, only the left side plate 51L will be described in this embodiment, and the description of the right side plate 51R will be omitted.

As shown in FIG. 4, the left side plate 51L is composed of two plate members in which pin holes 510 for inserting connecting pins 9, which will be described later, are formed on the same axis. The two plate members forming the left side plate 51L are opposed to each other with a width that allows insertion of the central upper portion (more specifically, the portion where the pin hole 35 is formed) of the vertical plate 33L (see FIG. 2) of the upper frame 30. do.

The subframe 5 is provided with a pin connecting device 6 (6L, 6R). The pin connecting device 6L is a device that connects the left side plate 51L forming the subframe 5 and the left vertical plate 33L forming the upper frame 30. As shown in FIG. The pin connecting device 6R is a device that connects the right side plate 51R that constitutes the subframe 5 and the right vertical plate 33R that constitutes the upper frame 30. As shown in FIG.

Since the pin connecting device 6L and the pin connecting device 6R have the same configuration, only the pin connecting device 6L arranged on the left side will be described in this embodiment, and the pin connecting device 6R arranged on the right side will be explained. Description is omitted.

As shown in FIG. 4, the pin connecting device 6L includes a hydraulic cylinder 7 including a cylinder rod 71 and a cylinder head 73, a pipe 8, a connecting pin 9, and a pressing plate 81. As shown in FIG.

The hydraulic cylinder 7 is a hydraulic cylinder that strokes in the machine width direction (horizontal direction). In other words, the hydraulic cylinder 7 is arranged such that the cylinder head 73 extends from the machine center side to the machine lateral side and contracts from the machine lateral side to the machine center side.

The cylinder head 73 has a flange 73</b>F that extends radially outward on the extension side end 73</b>E side and faces the extension side end 8</b>E of the pipe 8 . Note that the cross section of the cylinder head 73 is indicated by dotted hatching in FIG.

The pipe 8 is a cylindrical member that can be inserted through the body of the cylinder head 73 and surrounds the body of the cylinder head 73 . Note that the cross section of the pipe 8 is indicated by diagonal hatching in FIG.

The connecting pin 9 has a U-shaped cross-section through which the pipe 8 can be inserted. It is a cylindrical hydraulic pin that connects 51L and vertical plate 33L. Specifically, the connecting pin 9 is inserted into and removed from the pin hole 510 and the pin hole 35 by stroke operation of the hydraulic cylinder 7 (specifically, expansion and contraction of the cylinder head 73).

The holding plate 81 is fixed to the contraction side end 9S of the connecting pin 9 with a plurality of bolts BT, and has a circular shape extending toward the center side in the radial direction of the connection pin 9 and facing the contraction side end 8S of the pipe 8. plate. The cross section of the pressing plate 81 is indicated by hatching in a checkered pattern in FIG.

As shown in FIG. 7 , the pressing plate 81 has a protrusion 810 with a portion of the outer edge extending radially outward of the connecting pin 9 . Two blocks BL are provided on the protrusion 810 to prevent the pressing plate 81 from rotating. The two blocks BL are an example of a fixing member according to the present invention, and are arranged so as to sandwich the projecting portion 810 from both sides.

The pin connecting device 6R on the opposite side shown in FIG. 4 has the same configuration as the pin connecting device 6L, except that the expansion and contraction direction of the hydraulic cylinder is opposite to that of the pin connecting device 6L.

Next, referring to FIGS. 5 and 6, the state of each part when the connecting pin 9 is extended and contracted will be described.

First, when the cylinder head 73 extends to the side of the machine (left side), the extension side end 73E of the cylinder head 73 contacts the inner wall 91 of the connecting pin 9 . When the cylinder head 73 extends while the extension-side end 73E of the cylinder head 73 is in contact with the inner wall 91 of the connecting pin 9, the connecting pin 9 extends to the side of the machine (left side). Finally, as shown in FIG. 5, the connecting pin 9 is in the most extended state.

As shown in FIG. 5, when the cylinder head 73 is extended, the extension side end 73E of the cylinder head 73 contacts the inner wall 91 of the connecting pin 9, while the flange 73F of the cylinder head 73 and the extension side end of the pipe 8 are in contact with each other. A gap is formed between the portion 8E and the portion 8E.

On the other hand, as shown in FIG. 6, when the cylinder head 73 contracts toward the machine center (right side), the extension side end 73E of the cylinder head 73 moves away from the inner wall 91 of the connecting pin 9, and the flange 73F of the cylinder head 73 moves away from the inner wall 91 of the connecting pin 9. abuts the extended end 8E of the pipe 8.

When the cylinder head 73 is contracted while the flange 73F of the cylinder head 73 is in contact with the extension side end portion 8E of the pipe 8, the contraction side end portion 8S of the pipe 8 moves the pressing plate 81 toward the contraction side (machine center side). do. When the pressing plate 81 moves toward the contraction side (machine center side), the connecting pin 9 fixed to the pressing plate 81 also contracts.

According to the embodiment described above, by providing the pipe 8 between the connecting pin 9 and the cylinder head 73, the connecting pin 9 can be extended or contracted without fixing the connecting pin 9 and the cylinder head 73. It is possible. Therefore, the rotation of the connecting pin 9 due to rattling does not act on the cylinder head 73 and the sealing member (not shown) provided inside the cylinder head 73 is not damaged. As described above, the extension side end 73E of the cylinder head 73 is in contact with the inner wall 91 of the connecting pin 9 when the cylinder head 73 is extended. Since it slides against 73E, the cylinder head 73 does not rotate.

Further, according to the above-described embodiment, the pressing plate 81 is fixed to the contraction side end portion 9S (machine center side) of the connecting pin 9 with a plurality of bolts BT. Therefore, the plurality of bolts BT are not tensioned when the hydraulic cylinder 7 is extended with a relatively strong force, and the plurality of bolts BT are tensioned only when the hydraulic cylinder 7 is retracted with a relatively weak force. Therefore, the plurality of bolts BT that fix the pressing plate 81 are less likely to loosen.

Further, when a problem occurs in the hydraulic cylinder 7, it is necessary to remove (detach) the hydraulic cylinder 7 while the connecting pin 9 is attached. At that time, if the pressing plate 81 were fixed to the extension side end 9E (machine side) of the connecting pin 9 and there was a structure on the side of the machine, the hydraulic cylinder 7 could not be removed.

In this regard, in the above-described embodiment, since the pressing plate 81 is fixed to the contraction side end portion 9S (machine center side) of the connecting pin 9 with the bolt BT, the hydraulic cylinder 7 can be reliably removed when a problem occurs. is possible.

Further, according to the above-described embodiment, the pressing plate 81 has the projecting portion 810, and the projecting portion 810 is sandwiched and fixed between the blocks BL. Therefore, it is possible to suppress the rotation of the pressing plate 81 and thus the rotation of the connecting pin 9 fixed to the pressing plate 81 .

<2. Variation>
The pin coupling device and construction machine according to the present invention are not limited to the above-described embodiments, and various modifications and improvements are possible within the scope of the claims.

In the above-described embodiment, the inner wall 91 of the connecting pin 9 and the entire area of the extension side end portion 73E of the cylinder head 73 are in contact with each other when the connecting pin 9 is in the most extended state shown in FIG. is not limited to

As shown in FIG. 8, the inner wall 91 of the connecting pin 9 and the entire area of the extension side end portion 73E of the cylinder head 73 may be configured so as not to abut. Specifically, a recess 910 may be formed in a part of the inner wall 91 of the connecting pin 9 . By doing so, the portion of the inner wall 91 in which the recessed portion 910 is formed does not contact the extension side end portion 73</b>E of the cylinder head 73 .

According to the modified example described above, when the connecting pin 9 rotates due to rattling or the like, the frictional resistance generated between the inner wall 91 of the connecting pin 9 and the extension side end portion 73E of the cylinder head 73 is reduced. be able to.

Further, in the above-described embodiment, the pin connecting device 6 is used to connect the side plates of the sub-frame 5 and the vertical plates of the upper frame 30, but the present invention is not limited to this. For example, a pin connecting device 6 may be used to connect the boom and arm that constitute the work attachment 4 .

INDUSTRIAL APPLICABILITY As described above, the pin connecting device and construction machine according to the present invention are suitable for connecting two members constituting a hydraulic excavator.

1 hydraulic excavator, 2 lower running body, 3 upper rotating body, 4 work attachment,
5 subframe, 6 (6L, 6R) pin coupling device, 7 hydraulic cylinder, 8 pipe,
9 connecting pin, 30 upper frame, 31 bottom plate, 33 vertical plate, 35 pin hole,
51L left side plate, 51R right side plate, 71 cylinder rod, 73 cylinder head,
73F flange, 81 plate, 91 inner wall, 510 pin hole, 810 protrusion,
910 recess, BL block, BT bolt

Claims (4)

A pin connection device for connecting two members,
a hydraulic cylinder including a cylinder rod and a cylinder head;
a cylindrical pipe through which the body of the cylinder head can be inserted;
a cylindrical connecting pin having a U-shaped cross-section through which the pipe can be inserted inside and inserted into pin holes respectively formed in the two members to connect the two members;
a pressing plate fixed to the contraction side end of the connecting pin, extending radially toward the center of the connection pin and facing the contraction side end of the pipe;
with
The cylinder head has a flange extending radially outwardly of the cylinder head on the extension side end side and facing the extension side end of the pipe,
When the hydraulic cylinder is extended, the extension side end of the cylinder head contacts the inner wall of the connecting pin, while a gap is formed between the flange and the extension side end of the pipe,
A pin connecting device, wherein the flange abuts the extension side end of the pipe when the hydraulic cylinder is retracted. 2. The pin coupling device according to claim 1, wherein the inner wall against which the extension side end of the cylinder head abuts is partially formed with a recess. the pressing plate has a projection part of which part of the outer edge extends outward in the radial direction of the connecting pin;
3. The pin connecting device according to claim 1, wherein the protrusion is provided with a fixing member for preventing rotation of the pressing plate. construction machinery,
a first member having a first pin hole;
a second member having a second pin hole and connectable to the first member;
a hydraulic cylinder including a cylinder rod and a cylinder head, and arranged so that the cylinder head extends from the machine center side to the machine side side;
a cylindrical pipe through which the body of the cylinder head can be inserted;
A cylindrical connection that has a U-shaped cross-section through which the pipe can be inserted, and that connects the first member and the second member by being inserted through the first pin hole and the second pin hole. idea,
a pressing plate fixed to the contraction side end of the connecting pin, extending radially toward the center of the connection pin and facing the contraction side end of the pipe;
with
A flange extending outward in the radial direction and facing the extension side end of the pipe is provided at the extension side end of the cylinder head,
When the hydraulic cylinder is extended, the extension side end of the cylinder head contacts the inner wall of the connecting pin, while a gap is formed between the flange and the extension side end of the pipe,
A construction machine according to claim 1, wherein said flange abuts against an extension side end of said pipe when said hydraulic cylinder is retracted.

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