JPH09316917A - Openable work tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work tool which is openable with a hydraulic cylinder provided with a hydraulic shovel in an openable work tool to be mounted on the hydraulic shovel and which does not allow the angle of a boom or an arm which is mounted with the openable work tool to affect the direction of the openable work tool before opening or closing the tool by way of a wire rope. SOLUTION: An openable work tool 26 or a bucket is suspended turnably in the longitudinal direction to a fixing bracket 20 mounted on an arm 7 or the like of a hydraulic shovel. A tuning bracket 62 is mounted turnably vertically, centering on a pin 25. A support sheave 63 and a guide sheave 64 are mounted on the swivel bracket 62. The openable work tool 26 is provided with a spring 31 which energizes its opening direction. The openable work tool 26 is opened and closed by the expansion of a bucket cylinder 9 or the like while the turning bracket 62 is turned, responding with changes in the angle of a frame 27 with the arm 7 or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work tool mounting structure in which an openable and closable work tool such as a clamshell bucket, a grab bucket or a hawk grab is mounted on the tip of a boom or arm of a hydraulic excavator.

[0002]

2. Description of the Related Art FIG. 16 (A) is a side view showing a hydraulic excavator. In the hydraulic excavator, an upper revolving structure 3 is installed on a lower traveling structure 1 via a revolving device 2, and the upper revolving structure 3 is mounted on the upper revolving structure 3. ,
The boom 5 is attached by the boom cylinder 4 so that it can be raised and lowered freely.
An arm 7 is attached to the tip of the boom 5 by an arm cylinder 6 so as to be rotatable up and down. A backhoe bucket 8 is attached to the tip of the arm 7 so as to be rotatable around a pin 12, and the backhoe is connected by a bucket cylinder 9 via a link 10. The bucket 8 is rotated.

[0003] Such a hydraulic excavator is applied as various working machines by removing the backhoe bucket 8 and attaching various working tools according to the purpose. FIG.
(B) is an example thereof, in which the backhoe bucket 8 is removed, the clamshell bucket 11 is attached by hanging it through the pin 12 and the attachment 13, and the hydraulic cylinder 14 is expanded / contracted so that the clamshell bucket 11 is removed. It is opened and closed for excavation and soil removal.

In FIG. 17 (A), instead of the backhoe bucket 8, a hawk grab 16 is mounted in a tilt type so that its direction can be arbitrarily changed by a bucket cylinder 9, and the claws of the hawk grab 16 can be opened and closed. It is performed by a hydraulic cylinder 15 provided in the hawk grab 16. FIG.
7 (B) is an example in which the hawk grab 16 is attached by a pin 12 in a hanging manner. In this case, the hawk grab 16 is always in a vertical posture, and the claws of the hawk grab 16 are opened and closed by the hydraulic cylinder 15. Be seen.

Further, in FIG. 18, the pin 1 is directly connected to the arm 7.
This is an example in which the opening and closing fulcrum of the claw of the hawk glove 16 is attached by 2, and the hawk glove 16 is opened and closed by the bucket cylinder 9 via the links 17 and 18.

[0006]

However, as shown in FIG.
17B, FIG. 17A, and FIG. 17B are for opening and closing the clamshell bucket 11 and the hawk grab 16 by the hydraulic cylinders 14 and 15, so that the hydraulic excavator has hydraulic pipes for the hydraulic cylinders 14 and 15. Must be installed and the excavator body must be modified. Moreover, since the hydraulic cylinders 14 and 15 are used, the cost is high.

On the other hand, in the structure in which the hawk grab 16 is directly connected to the arm 7 as shown in FIG. 18, the opening degree of the hawk grab 16 is uniquely determined by the extension amount of the bucket cylinder 9, for example. Depending on the position of the object 19 to be grasped, work may be impossible.

In view of the above-mentioned problems, the present invention is a hydraulic cylinder equipped with an openable work implement such as a clamshell bucket, a hawk grab or a grab bucket without modifying the hydraulic excavator and provided in the hydraulic excavator. In addition, when opening and closing the openable work implement via the wire rope with an actuator such as a hydraulic cylinder equipped in the hydraulic excavator, the boom or arm to which the openable work implement is attached must be at the angle of the openable work implement. An object is to provide a retractable work tool that does not affect the orientation.

[0009]

According to a first aspect of the present invention, a fixed bracket is detachably attached to the tip of an arm or a boom of a hydraulic excavator, and a pin is attached to the fixed bracket through a clamshell bucket, a grab bucket, or a hawk grab. Any of the openable and closable work implements is rotatably hung in the front-rear direction, and a rotary bracket is attached so as to be vertically rotatable around the pin, and the openable and closable at a position eccentric to the pin of the rotary bracket. While attaching a support sheave for hanging a wire rope for supporting the work implement, a guide sheave is attached at a position eccentric to the opposite side of the support sheave about the pin of the rotating bracket, and the opening-closing work implement is The operation member for opening and closing is built in such that it can move along the frame hung by the pin, and it is attached in the opening direction of the opening and closing work tool. A wire rope connected to the rod tip of a bucket cylinder or an arm cylinder attached to the arm or boom is passed between a support sheave attached to the rotating bracket and a guide sheave to be linked to the operation member. The expansion / contraction of the bucket cylinder or the arm cylinder opens / closes the opening / closing-type work tool, and the rotating bracket rotates about the pin according to a change in the angle of the frame with respect to the arm or the boom. It is characterized by

According to a second aspect, in the first aspect, a movable member is provided in the frame so as to be vertically movable with respect to the frame and the operating member, and the wire rope is provided between the movable member and the operating member. The elastic member that absorbs the pulling force is inserted, and the tip end of the wire rope is connected to the movable member instead of being connected to the operation member.

[0011] Claim 3 is based on claim 1 or 2,
A mounting frame in which the frame of the open / close-type work implement is rotatably attached to the pin in the front-rear direction, and a main body attached to the mounting frame so that the rotational position can be adjusted about a longitudinal centerline. And a frame.

According to a fourth aspect of the present invention, a chain is used in place of the wire rope, and a sprocket or roller is used in place of the sheave. In addition, claim 5
Uses a roller for at least one of the support sheave and the guide sheave. A sixth aspect uses a coil chain as the chain of the fourth aspect.

[0013]

According to the present invention, when the bucket cylinder or the arm cylinder attached to the arm or the boom is contracted or extended, the operating member is pulled up against the spring provided in the openable work implement to close the openable work implement. When the bucket cylinder or arm cylinder is extended or contracted, the opening / closing work tool is opened by the force of the spring. When the angle of the frame with respect to the arm or boom changes due to pulling up and down of the openable work implement, the pivot bracket pivots around the pin,
The length of the wire rope from the feeding position of the wire rope between the support sheave and the guide sheave to the operation member connection point becomes almost constant, and the vertical movement of the operation member due to the change in the angle of the arm or boom is suppressed, and the angle It is prevented that the changeable work implement is opened and closed due to the change.

In the present invention, the pulling force of the wire rope is absorbed by the elastic material interposed between the operating member and the movable member, and the wire rope feeding portion is provided between the support sheave and the guide sheave. Depending on the change in the distance to the movable member, the elastic material expands and contracts to absorb the displacement,
The opening and closing of the bucket can be prevented more completely.

According to the third aspect of the present invention, by changing the orientation of the main frame with respect to the mounting frame of the releasable work implement, the orientation of the releasable work implement with respect to the arm or the like can be changed in accordance with the topography of the site and the workability. Is improved. Similar effects can be obtained by using a chain instead of the wire rope and using a sprocket or a roller instead of the sheave as in claims 4 to 6.

[0016]

1 (A) is a side view showing an embodiment of the present invention in which a clamshell bucket is attached to a hydraulic excavator, and FIG. 1 (B) is an enlarged sectional view taken along the line EE of FIG. 1 (A). FIG. 1 (C) is an enlarged F arrow view of FIG. 1 (A). 2 is an enlarged view of a main part of FIG. 1 (A), FIG. 3 is an enlarged cross-sectional view of GG in FIG. 2, and FIG. 4 (A) is an enlarged cross-sectional view of H-H in FIG.
4B and 4C are cross-sectional views taken along the line I-I of FIG.
5 is a sectional view taken along line JJ, FIG. 5A is a sectional view taken along line KK in FIG.
5B and 5C are cross-sectional views taken along line LL in FIG.
FIG. 6 is a partial cross-sectional side view showing a state in which the openable work implement of the present embodiment is opened.

As shown in FIG. 1A, the present invention uses a hydraulic excavator as a base machine. In this embodiment, a fixing bracket 2 is attached to the tip of an arm 7 of the hydraulic excavator.
0 is attached detachably. The fixing bracket 20 is attached by fixing the fixing bracket 20 to the attaching hole of the backhoe bucket with a pin 21 and covering the outer periphery of the arm 7 from above as shown in FIGS. 1 (B) and 2 (A). A hole 20a provided with a threaded rod 23 on the band 22 and the threaded rod 23 provided on the base end side of the fixed bracket 20.
And a nut 24 is screwed into the threaded rod 23 and tightened.

A clamshell bucket 26 is suspended from the fixing bracket 20 via a pin 25. As shown in FIGS. 2 and 3, the clamshell bucket 26
Includes a rod-shaped operating member 28 for opening and closing so as to be movable along a cylindrical frame 27 hanging from the fixed bracket 20, and a spring receiver 29 provided on the operating member 28 and the inside of the frame 27. Spring receiver 30 provided in
And a spring 31 for urging the bucket 26 in the opening direction.
Intervene.

As shown in the side views of FIGS. 7 and 8 which are comparative examples of the present invention, the operating member 28 and the wire rope 37 for opening and closing the bucket are directly connected (41 indicates a connection point) to be linked. Alternatively, in the present embodiment, the wire rope 37 is connected to the operating member 28 via the movable member 51 so that they are linked to each other. The movable member 51 is attached to the operation member 28 and the frame 27 so as to be able to move up and down, and a spring that biases the movable member 51 in a direction to push it down between the spring receiver 52 of the movable member 51 and the spring receiver 29 of the operation member 28. Intervene 53.

As shown in FIGS. 2, 3 and 4, rods 54 are fixed to the upper portions of the left and right shells 32, and the rods 54 are fixed.
Inner and outer arms 55 and 56 are welded to each other, the outer arm 56 is connected to the outside of the frame 27 by a pin 57, while the link 60 is connected to the lower portion of the operating member 28 by a pin 59. An inner arm 55 is connected to the lower end by a pin 61. Therefore, when the operating member 28 moves up and down with respect to the frame 27, the shell 32
Rotates around the pin 57, and the bucket is opened and closed. Needless to say, the opening / closing structure of the bucket 26 is not limited to this example, as shown in FIG. 7 and FIG.
A structure in which the inside of the upper portion of the shell 32 is connected to the lower end of the operation member 28 by a pin 30 and the outside of the shell 32 is connected to the frame 27 by a link 34 and pins 35 and 36 can be adopted.

As shown in FIGS. 1 (C) and 2, the starting end of the wire rope 37 for opening and closing the bucket is connected to a connector 39 attached to a pin 38 connecting the link 10 and the rod of the bucket cylinder 9. The intermediate portion is passed through the support sheave 63 and the guide sheave 64 attached to the rotating bracket 62 attached to the fixed bracket 20. The rotating bracket 6
2 to 4, a rotating bracket 62 is attached so as to be vertically rotatable about the pin 25, and the rotating bracket 62 is eccentrically located on the arm 7 side with respect to the pin 25. The support sheave 63 is attached, and the guide sheave 64 is attached to the pivot bracket 62 at a position eccentric to the side opposite to the support sheave 63 about the pin 25.

In this structure, when the bucket cylinder 9 is extended from the state shown in FIG. 2, the operating member 28 is pushed down by the spring 31 to open the bucket 26 as shown in FIG. 6, and the bucket cylinder 9 is contracted. Spring 3
Bucket 26 closes against the forces of 1, 53.

In FIG. 7 showing a comparative example, a supporting sheave 40 is attached to the fixed bracket 20, a wire rope 37 is hung on the supporting sheave 40 and connected to the operating member 28. According to this comparative example, As shown in the drawing, when the angle θ1 formed by the arm 7 and the clamshell bucket 26 is small, and when the angle θ1 is large as shown in FIG. 8, the rope around the sheave 40 is used. Since the lengths are different, when the arm 7 is lowered from the state of FIG. 7 to the state of FIG.
There is a problem that 6 opens.

FIG. 9 is a diagram for explaining this, where c is the central axis of the bucket 26 when the angle θ1 of the clamshell bucket with respect to the arm 7 is small as shown in FIG. 7, and d is the arm 7 as shown in FIG. The central axis of the bucket 26 when the angle θ2 of the clamshell bucket with respect to
Is the angle difference of (θ2-θ1), r is the radius of the sheave 40, and θ3 is the sheave 40 of the wire rope 37 in the case of FIG.
9 shows the contact angle that decreases when the state changes to the state of FIG. As shown in FIG. 9, by changing from the state of FIG. 7 to the state of FIG. 8, the distance from the pin 25 to the connection point 41 of the operating member 28 of the wire rope 37 becomes longer from L1 to L2, and the bucket cylinder 9 The bucket 26 will be opened even though is not expanded or contracted.

On the other hand, according to this embodiment, FIG. 10 (A) drawn corresponding to FIG. 7 and FIG. 10 drawn corresponding to FIG.
As shown in (B), when the direction of the clamshell bucket 26 with respect to the arm 7 changes from c to d, and the angle between them increases by Δθ, the wire rope 37
Since it passes between the support sheave 63 and the guide sheave 64, the rotation bracket 6
2 rotates. Here, the wire rope 37 is connected to the pin 25.
As it passes near the center of the
Even if the angle of the clamshell bucket 26 with respect to changes, the distance L3 from the pin 25 to the connection point of the movable member 51 of the wire rope 37 (when the angle is small as θ1), L4 (when the angle is θ2). Is substantially the same as that of the bucket 7), the opening and closing of the bucket 26 due to a change in the angle formed by the arm 7 and the clamshell bucket 26 can be prevented.

Further, in this embodiment, the wire rope 37 is not directly connected to the operating member 28, but the spring 5 is used.
Since it is connected via the movable member 51 biased by 3, the bucket 2 due to the small difference between L3 and L4
It is possible to eliminate the slight opening and closing of 6. That is,
From the relationship between the radius of the support sheave 63 and the radius of the wire rope 37, it is structurally impossible to completely set L3 = L4, but the spring 53 interposed between the operating member 28 and the movable member 51 causes the wire The pulling force of the rope 37 is absorbed, and the spring 53 is expanded and contracted to absorb the displacement in accordance with the change in the distance between the movable member 51 and the feeding portion of the wire rope 37 between the support sheave 63 and the guide sheave 64. By doing so, the opening and closing of the bucket 26 can be prevented more completely.

In this embodiment, as shown in FIGS. 2 and 3 and FIGS. 11A and 11B, the frame 27 of the bucket 26 is attached to the pin 25 so as to be rotatable in the front-rear direction. Mounting frame 27a, flanges 27b and 27c and bolts 65 for the mounting frame 27a,
Main frame 27 that is detachably connected by a nut 66
and the operating member 2 on the main frame 27d.
8 and the shell 32 is attached to the main frame 2
By attaching 7d so that the rotational position can be adjusted about the longitudinal centerline O, as shown in FIG. 11 (B), the orientation of the bucket 26 can be changed with respect to the central axis line x of the arm 7 depending on the situation of the site. It can be set arbitrarily, improving workability.

In the above embodiment, the spring 31 for opening the bucket 26 is mounted inside the frame 27.
As shown in FIG. 12, an arm 56 provided on the shell 32 is extended to the outside to provide a spring receiving portion 56a, and the spring receiving portion 27 provided outside the spring receiving portion 56a and the frame 27.
The bucket 26 may be biased in the opening direction by providing a tension spring 67 between the bucket 26 and e. Also,
As shown in FIG. 13, a push spring 58 may be interposed between the left and right rods 54 of the shell 32 to urge the bucket 26 in the opening direction. If the springs 67 and 68 are attached to the outside of the frame 27 as shown in FIGS. 12 and 13, the frame 27 can be made short and compact.

In the above-mentioned embodiments, the openable work implement is a clamshell bucket, but the present invention is also applicable to a hawk grab and a grab bucket. Further, as shown in FIG. 14 (A), a structure in which a hydraulic cylinder 70 for adjusting the angle of the opening / closing work tool with respect to the arm 7 is attached between the fixed bracket 20 and the frame 27, or in FIG. 14 (B). As shown, the fixing bracket 20 and the frame 27 may be connected by a link 71. When the cylinder 70 for angle adjustment as shown in FIG. 14A is provided, if the hawk glove 16 is provided as an openable work implement as shown in the figure, the orientation of the hawk glove 16 is set at an angle according to the work site. it can. Also, as shown in FIG. 14B, even when the link 71 is provided, the angle between the arm 7 and the openable work implement 16 can be fixed at an arbitrary angle, and at the same time, the swing of the openable work implement 16 is prevented. The workability is improved. Further, the open / close type working tool may be hung down from the boom 5 instead of being hung from the arm 7, and the open / close type working tool may be opened / closed by the arm cylinder 6.

Further, instead of the wire rope 37 for opening and closing, as shown in FIG. 15 (A), a chain 74 that engages with a sprocket, such as a roller chain or a block chain, is used, and instead of the sheaves 63 and 64. Sprocket 72, 73 may be used, as shown in FIG. 15 (B), both sheaves 63, 64 may be provided with roller 75 on one side as shown, and further shown in FIG. 15 (C). As shown, using the coil chain 76, the sheave 63,
Instead of 64, rollers 77, 78 may be used. The use of the coil chain 76 has the advantages that it can be easily connected to the bucket cylinder 9 and the operating member 28 and that it can withstand a large load. Further, rubber may be used instead of the spring 53 as an elastic material that presses the spring 31 for opening the openable work implement and the movable member 51.

[0031]

According to the first, fourth and fifth aspects of the present invention, since the open / close type work implement is opened / closed by using the bucket cylinder or the arm cylinder of the hydraulic cylinder, the open / close type work implement is not modified. Since the work implement is attached and the open / close type work implement can be opened and closed with the bucket cylinder and arm cylinder provided in the hydraulic excavator, it is not necessary to modify the hydraulic piping of the hydraulic excavator, and the backhoe bucket replacement attachment is provided at low cost. it can.

Even if the orientation of the open / close-type work implement changes with respect to the arm, the open / close-type work implement is moved from the wire rope feeding portion between the sheaves by the rotation of the rotating bracket to which the support sheave and the guide sheave are attached. There is almost no change in the distance to, and it is not necessary to consider changing the orientation of the retractable work tool with respect to the arm during work.

According to the second aspect, the wire rope is not directly connected to the operating member but is connected to the movable member biased in the opening direction by the elastic member, so that the pulling force of the wire rope is absorbed by the elastic member. Therefore, it is possible to completely prevent the opening / closing of the opening / closing work tool due to a change in the angle of the opening / closing work tool frame with respect to the arm or the boom.

According to the third aspect, the direction of the openable work implement can be changed according to the situation of the site, and the workability is improved.

According to the sixth aspect, there is an advantage that the cylinder and the operating member can be easily connected and a large load can be endured.

[Brief description of drawings]

1A is a side view showing an embodiment of the present invention in which a clamshell bucket is attached to a hydraulic excavator, FIG. 1B is an enlarged sectional view taken along line EE of FIG. 1A, and FIG. FIG.

FIG. 2 is an enlarged view of a main part of FIG.

3 is an enlarged cross-sectional view taken along line GG of FIG.

4A is an enlarged sectional view taken along line HH of FIG. 2, FIG.
(C) is the II sectional view and JJ sectional view of (A), respectively.

5A is a sectional view taken along line KK of FIG. 2, FIGS.
3A is an LL sectional view and an MM sectional view of FIG.

FIG. 6 is a partial cross-sectional side view showing a state in which the openable work implement of the present embodiment is opened.

FIG. 7 is a side view showing a comparative example of the present invention when the angle between the arm and the retractable work tool is small.

FIG. 8 is a side view showing a comparative example of FIG. 7 in the case where the angle between the arm and the opening / closing work tool is large.

FIG. 9 is an explanatory view of the operation of the comparative example of FIGS. 7 and 8.

10 (A) and 10 (B) are explanatory views of the operation of the above embodiment.

11A is an enlarged cross-sectional view taken along the line P-P of FIG. 2, and FIG. 11B is an explanatory view of the action of the mounting structure for the retractable work tool of the embodiment.

FIG. 12 is a sectional view showing another embodiment of the present invention.

FIG. 13 is a sectional view showing another embodiment of the present invention.

14A and 14B are sectional views showing another embodiment of the present invention.

15A to 15C are views showing another configuration example of the rotating bracket in the present invention.

16A is a side view of a hydraulic excavator, and FIG. 16B is a side view of a conventional clamshell configured using the hydraulic excavator as a base machine.

17 (A) and 17 (B) are side views showing an example of a conventional mounting structure for a hydraulic excavator of a fork grab.

FIG. 18 is a side view showing an example of a conventional attachment structure for a hydraulic excavator of a hawk grab in a working state.

[Explanation of symbols]

1: Lower traveling body, 2: Revolving device, 3: Upper revolving body, 4:
Boom cylinder, 5: boom, 6: arm cylinder,
7: Arm, 8: Backhoe Bucket, 9: Bucket Cylinder, 10: Link, 20: Fixed Bracket, 21:
Pin, 22: Band, 23: Screw rod, 24: Nut, 25: Pin, 26: Clamshell bucket, 27:
Frame, 27a: mounting frame, 27d: main frame, 28: operating member, 31: spring, 32: shell, 3
4: Link, 37: Wire rope, 39: Bracket,
40: sheave, 41: connection point, 51: movable member, 53:
Auxiliary spring, 62: rotating bracket, 63: support sheave,
64: guide sheave, 67: tension spring, 68: push spring, 72, 73: sprocket, 74: sprocket chain, 75: roller, 76: coil chain, 7
7, 78: Laura

Claims (6)

[Claims] 1. A fixed bracket is removably attached to the tip of an arm or boom of a hydraulic excavator, and an openable / closable work tool of any one of a clamshell bucket, a grab bucket, and a hawk grab is attached to the fixed bracket via a pin. It is rotatably suspended in the front-rear direction, and a pivot bracket is attached so as to be pivotable up and down about the pin. A support sheave to be hung is attached, and a guide sheave is attached at a position eccentric to the side opposite to the support sheave around the pin of the rotating bracket, and the opening / closing work implement follows the frame suspended by the pin. And a spring for urging the opening-and-closing type work tool in the opening direction. A bucket cylinder or arm cylinder attached to a rod or a boom, and a wire rope connected to the rod tip of the bucket cylinder or arm cylinder is passed between a support sheave attached to the rotating bracket and a guide sheave so as to be linked to the operation member. The opening / closing operation tool is opened / closed by expansion / contraction of a cylinder or an arm cylinder, and the rotation bracket is rotated about the pin according to a change in an angle of the frame with respect to the arm or boom. Work implement. 2. The pulling force of the wire rope according to claim 1, wherein a movable member is provided in the frame so as to be vertically movable with respect to the frame and the operation member, and the pulling force of the wire rope is provided between the movable member and the operation member. An openable work tool, characterized in that an elastic material for absorbing heat is interposed, and a tip of the wire rope is connected to the movable member. 3. The mounting frame according to claim 1, wherein the frame of the opening / closing work implement is mounted on the pin so as to be rotatable in the front-rear direction, and a longitudinal centerline with respect to the mounting frame. An openable and closable work tool comprising a main frame mounted so that a turning position can be adjusted as a center. 4. The openable work implement according to claim 1, wherein a chain is used instead of the wire rope, and a sprocket or a roller is used instead of the sheave. 5. The openable work implement according to claim 1, wherein a roller is used for at least one of the support sheave and the guide sheave. 6. The openable work implement according to claim 4, wherein a coil chain is used as the chain.