JP2537512Y2 - Hydraulic excavator - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a hydraulic excavator, and more particularly to a hydraulic excavator that can maintain an angle of an arm with respect to the ground even when an upper boom is pivoted.

[0002]

2. Description of the Related Art One example of a conventional hydraulic power shovel is shown in a side view in FIG. The hydraulic power shovel has a lower traveling body 51 and an upper revolving superstructure 44 rotatable on a vertical axis on the lower traveling body 51. The rear end of the lower boom 40 is pivotally attached to the upper swing body 44,
A rear end of the upper boom 41 is pivotally attached to a front end of the lower boom 40, and an arm 42 is pivotally attached to a front end of the upper boom 41. A sub arm 46 is mounted on the front end of the arm 42 so as to be rotatable around an axis (XX), and a bucket 43 is pivotally mounted on the front end of the sub arm 46.

As driving means for these members, a lower boom cylinder 50 is provided between the lower boom 40 and the upper swing body 44, and an upper boom cylinder 49 and an upper boom 4 are provided between the upper boom 41 and the lower boom 40.
1 and the arm 42, and the bucket cylinder 4 between the sub-arm 46 and the bucket 43.
7 are mounted on the arm 42, and a rotation device 48 for rotating the sub arm 46 around the axis (XX) with respect to the arm 42 is mounted on the arm 42.

[0004]

In the conventional hydraulic power shovel as described in FIG. 3, since the boom is divided into a lower boom 40 and an upper boom 41, the arm 42 and the sub arm 46 are positioned vertically. Excavation work can be performed, but if the arm 42 and the sub-arm 46 are to be moved up and down while the angle of the arm 42 and the sub-arm 46 to the ground, that is, the ground angle is kept constant, the lower boom cylinder 50, the upper The three actuators of the boom cylinder 49 and the arm cylinder 45 must be operated at the same time, and the operation is extremely complicated. In particular, when the upper boom 41 is pivoted up and down, a change in the ground angle of the arm 42 and the sub arm 46 becomes larger than when the lower boom 40 is pivoted up and down, and the arm 42 and the sub arm 46 are vertically moved. It is extremely difficult to operate the lower boom cylinder 50 and the upper boom cylinder 49 simultaneously to move the arm 42 and the sub-arm 46 up and down while maintaining the pressure.

[0005]

SUMMARY OF THE INVENTION The present invention provides a lower traveling body, an upper revolving body rotatably mounted on the lower traveling body, and a lower boom having a rear end pivotally attached to the upper revolving body. An upper boom having a rear end pivotally attached to a front end of the lower boom by a first pin; an arm having a rear end pivotally attached to a front end of the upper boom by a second pin; Hydraulic excavator having a bucket connected to the lower boom and an upper boom cylinder interposed between the upper boom and the lower boom, a rear end pivotally connected to a front end of the lower boom by a third pin. And an arm cylinder having a front end pivotally connected to a rear end of the arm by a fourth pin,
The distance between the first pin and the third pin is equal to the distance between the second pin and the fourth pin, and the distance between the third pin and the fourth pin by the arm cylinder. Can be equal in length to the distance between the first pin and the second pin.

[0006]

According to the present invention, the third operation is performed by the arm cylinder.
When the distance between the first pin and the fourth pin is set to a length equal to the distance between the first pin and the second pin, a straight line connecting the first pin and the third pin and the second pin The straight line connecting to the fourth pin is always kept parallel.
That is, an arm pivotally attached to the arm cylinder, an upper boom pivotally attached to the arm, a lower boom pivotally attached to the upper boom, and an arm cylinder pivotally attached to the lower boom constitute a parallelogram link. Accordingly, even if the upper boom is pivoted up and down by operating the upper boom cylinder, the ground angle of the arm is kept constant unless the arm cylinder and the lower boom cylinder are operated. Thus, by operating only the upper boom cylinder, the arm can be translated while maintaining a constant angle to the ground.

[0007]

1 and 2 show an embodiment of the present invention.
This will be described with reference to the drawings. FIG. 1 is a side view of a hydraulic power shovel according to an embodiment of the present invention, and FIG. 2 is a side view for explaining the operation of the embodiment. An upper revolving unit 2 is mounted above a lower traveling unit 1 formed of, for example, a crawler so as to rotate around a vertical axis. Although not shown, an cab, an engine, a hydraulic motor, a hydraulic pump, and the like are provided in the upper swing body 2. Upper revolving superstructure 2
, The rear end of the lower boom 4 is pivotally connected by a pin 16, and the lower boom 4 is pivotable about the pin 16 in a vertical direction. This pivoting of the lower boom 4 is effected by the lower boom cylinder 3 which is pivotally connected to the lower boom 4 at the front end by a pin 17 and to the upper swing body 2 at the rear end by a pin 15. A rear end of the upper boom 6 is pivotally connected to a front end of the lower boom 4 by a pin 18.
Up and down pivoting of the upper boom 6 around the pin 18 is performed by an upper boom cylinder 5 having a front end pivotally connected to the upper boom 6 with a pin 19 and a rear end pivotally connected to the lower boom 4 with a pin 32. A rear end of the arm 8 is pivotally connected to a front end of the upper boom 6 by a pin 22. The arm 8 has an axis (X
-X). The rotation of the support member 34 with respect to the arm 8 is performed by a rotation device 31 such as a hydraulic motor provided on the arm 8.

The rear end of the sub arm 10 is pivotally connected to the support member 34 with a pin 23. The sub-arm 10 is pivoted by a sub-arm cylinder 9 having a front end pivotally attached to the sub-arm 10 with a pin 25 and a rear end pivotally attached to the support member 34 with a pin 24. The bucket 12 is pivotally attached to the front end of the sub arm 10 via a pin 29. One end of a rod 14 is pivotally connected to the bucket 12 via a pin 28, one end of a link 13 is pivotally connected to the sub-arm 10 via a pin 33, and the other end of the rod 14 and the other end of the link 13 are 27 for pivotal connection. This pin 27
Also, the front end of the bucket cylinder 11 is pivotally connected, and the rear end of the bucket cylinder 11 is pivotally connected to the sub arm 10 with a pin 26. The pivoting of the bucket 12 is performed by the bucket cylinder 11.

What is notable in the present invention is that the arm cylinder 7 is interposed between the arm 8 and the lower boom 4. That is, the front end of the arm cylinder 7 is pivotally attached to the rear end of the arm 8 by the pin 21,
The rear end of the arm cylinder 7 is pivotally connected to the front end of the lower boom 4 by a pin 20. The distance between the pin 18 and the pin 20 is equal to the distance between the pin 22 and the pin 21, and the pin 20 and the pin 2
1 can be equal in length to the distance between pins 18 and 22. Thus, when the distance between the pin 20 and the pin 21 is set to the above-described length by the arm cylinder 7, the pin 21 and the pin 2
A parallelogram link pivoted at 2, pin 18, and pin 20 is configured.

The operation of the present invention will be described with reference to FIG. When only the upper boom cylinder 5 is extended and retracted by the above-described parallelogram link, the arm 8 and the sub arm 1 are moved as shown by the solid line and the imaginary line in FIG.
The ground angle of 0 is kept constant, and the arm 8 and the sub-arm 10 move up and down. Of course, when the ground angle between the arm 8 and the sub arm 10 is to be changed, the arm cylinder 7 may be operated, and in this case, the same operation as the conventional one can be performed.

The hydraulic excavator shown in FIG.
A rotation device 31 is provided on the arm 8, and the support member 34, the sub arm 10, the sub arm cylinder 9,
The axis of the bucket 12 and the bucket cylinder 11 (X
Since it is configured to be able to rotate around −X), the degree of freedom of these members is large, and various excavations such as trench excavation and excavation around obstacles can be performed. Further, the present invention is useful for leveling work and finishing work such as the side surface shape of a groove. Therefore, positioning and trajectory control of the bucket 12 are particularly important. Then, it is required to frequently move the arm 8 and the sub arm 10 up and down or to move back and forth while keeping the ground angle of the arm 8 and the sub arm 10 constant.

According to this embodiment, when only the upper boom 6 is pivoted up and down in a state where the above-described parallelogram link is formed, the angle of the arm 8 and the sub arm 10 with respect to the ground does not change, and the arm 8 and the sub arm 10 do not change. As shown in FIG. 2, the sub arm 10 moves up and down in parallel (along with forward and backward movement). In addition, by almost exclusively concentrating on the operation of the upper boom cylinder 5 and the lower boom cylinder 3 (although the operation of the arm cylinder 7 is required as an auxiliary operation), the arm 8 and the sub arm 10 can be moved only in the front and rear directions. Can also. Further, when the hydraulic power shovel is operated by automatic control, the number of objects to be controlled is reduced and control is facilitated.

In the embodiment described above, the arm 8 is provided with the rotating device 31 and the rotating bearing 30 so that the sub-arm 10 can be rotated around the axis (XX). The present invention is applicable to a hydraulic excavator that does not have such a rotating means. The present invention is also applicable to a hydraulic power shovel having no sub arm cylinder shown in FIG.

[0014]

According to the hydraulic power shovel of the present invention, the ground angle of the arm is kept constant even when the upper boom is pivoted up and down in the state where the above-described parallelogram link is formed, whereby the arm Can be translated. In the operation of moving the arm up and down and back and forth while maintaining the angle to the ground of the arm, the worker can concentrate on the operation of the lower boom cylinder and the upper boom cylinder, and the burden on the worker can be reduced. Further, the present invention makes it easy to control the hydraulic excavator even when it is operated by automatic control.

[Brief description of the drawings]

FIG. 1 is a side view of a hydraulic power shovel according to an embodiment of the present invention.

FIG. 2 is a side view of the hydraulic power shovel for explaining the operation of the embodiment.

FIG. 3 is a side view of a conventional hydraulic power shovel.

[Explanation of symbols]

 Reference Signs List 1 traveling body 2 upper revolving structure 3 lower boom cylinder 4 lower boom 5 upper boom cylinder 6 upper boom 7 arm cylinder 8 arm 9 sub arm cylinder 10 sub arm 11 bucket cylinder 12 bucket 13 link 14 rod 15 pin 16 pin 17 pin 18 pin 19 pin 20 Pin 21 Pin 22 Pin 23 Pin 24 Pin 25 Pin 26 Pin 27 Pin 28 Pin 29 Pin 30 Rotating bearing 31 Rotating device 32 Pin 33 Pin 34 Support member

Claims (1)

(57) [Scope of request for utility model registration] An undercarriage (1), an upper revolving body (2) rotatably mounted on the undercarriage (1),
A lower boom (4) having a rear end pivotally attached to the upper rotating body (2); and an upper boom (2) having a rear end pivotally attached to a front end of the lower boom (4) by a first pin (18). 6) and an arm (8) having a rear end pivotally connected to a front end of the upper boom (6) by a second pin (22).
And a bucket (12) connected to the arm (8).
And a hydraulic excavator having an upper boom cylinder (5) interposed between the upper boom (6) and the lower boom (4), wherein a third pin ( 20) an arm cylinder (7) pivotally connected at its rear end by a pin (20) and at its rear end by a fourth pin (21) at the rear end of said arm (8); (18) and the distance between the third pin (20) and the second pin (2
Equal to the distance between 2) and said fourth pin (21),
The third pin (2) is moved by the arm cylinder (7).
0) and the distance between the fourth pin (21) and the first pin (21).
A hydraulic excavator characterized in that the length can be equal to the distance between the first pin (18) and the second pin (22).