JPH074069A - Grab pawl device for power shovel - Google Patents

Abstract

PURPOSE:To provide a small-sized light-weight grab pawl device, in which components are decreased and which also has operability and which has novel structure, regarding the grab pawl device mounted at the front end of the boom of a power shovel and used for demolishing a wooden house and used for the transport and installation, etc., of a heavy article. CONSTITUTION:In a grab pawl device 15 set up at the front end of the boom 1 of a power shovel and operated by the hydraulic system of the power shovel, a pawl 2 pivotally supported to a first fixed fulcrum 4 and a pawl 3 rotatably supported to a second fixed fulcrum 6 through a swinging bearing link 7 are provided. Both pawls 2, 3 are supported pivotally and connected by a connecting pin 9 at a position nearer to the opposite side than each swinging fulcrum 4, 8. The connecting pin 9 is placed at approximately the apex position of an isosceles triangle using the two swinging fulcrum 4, 8 as base both ends, and driven and coupled to a front link 11 driven forward and backward by a hydraulic cylinder at a position outer than the swinging fulcrum 4 of one pawl 2 or a cylinder rod through a driving pin 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gripper device mounted on the tip of a boom of a power shovel and used for dismantling a wooden house or for carrying and installing heavy objects.

[0002]

2. Description of the Related Art The claw of a gripping claw device of this type is normally pivotally attached to the tip of a boom of a power shovel and is opened and closed by a bucket rocking cylinder of the power shovel. When swinging the gripping pawl device, attach the gripping pawl device to the tip of the boom through the swing bracket, and swing the swing bracket with the bucket swing cylinder to open and close the claw opening / closing device. It is usual to mount the hydraulic cylinder on the swing bracket separately.

The structure of the conventional gripping claw device of this type can be roughly classified into three types of structures shown in FIGS. In the structure of FIG. 9, a pair of claws 2 and 3 are pivotally supported on one fixed fulcrum 4, and drive pins 10 and 22 are provided on the claws 2 and 3, respectively.
The drive links 11 and 23 are respectively connected to the drive pins 10 and 22.
The two drive links 11 and 23 are simultaneously operated by one hydraulic cylinder to synchronously open and close the two pawls 2 and 3.

In the structure shown in FIG. 10, a pair of pawls 2 and 3 are pivotally supported on two fixed fulcrums 24 and 25, respectively, which are provided separately from each other, and the drive link 11 or the cylinder rod 12 is attached only to one of the pawls 2. The one claw 2 and the other claw 3 are drivingly connected to each other via a link 26 provided near the swing fulcrum of the two, and the opening / closing operation of the one claw 2 is performed by the link 26.
It is transmitted to the other claw 3 via the to open and close the two claws 2 and 3 synchronously.

In the structure shown in FIG. 7, one of the pair of claws 2 and 3 is pivotally supported by a fixed fulcrum 4, and the other claw 2 is provided outside the swing fulcrum of the one claw 3. 9 and a pin 27 at the tip of the link lever 5 pivotally supported on the second fixed fulcrum 6, and the link lever 5 is connected to the drive link or the cylinder rod 12.

[0006]

The various types of structures used as the structure of the gripper device are as follows.
This is because each has advantages and disadvantages. For example, the structure shown in FIG. 9 requires two drive links, which complicates the structure on the drive side and makes the work of mounting the gripper device on the boom troublesome. Further, in the structure of FIG. 10, since the two fixed fulcrums are arranged in the direction orthogonal to the boom, a bracket is indispensable, and it is easy to force transmission of force from one claw to the other claw, so avoid this. Then, the opening / closing angle of the claw is limited, and the structure of the connecting link becomes complicated (for example, a structure in which a plurality of links are used for connection). Further, the structure of FIG. 11 has a small number of constituent members and can be made small and lightweight, but since the operation of the two claws at the time of opening and closing is different, there is an advantage and disadvantage in that it requires habituation in operation.

SUMMARY OF THE INVENTION The present invention has been made in view of the problem of obtaining a grasping pawl device having fewer defects, and an object thereof is to provide a grasping pawl device having a novel structure which has never been available.

[0008]

A gripping pawl device for a power shovel according to the present invention is a gripping pawl device 15 mounted on the tip of a boom 1 of a power shovel and operated by a hydraulic device of the power shovel. Fixed fulcrums 4, 13, 1
7 is provided with a pawl 2 pivotally supported and a pawl 3 pivotally supported by a second fixed fulcrum 6, 43, 18 via a swing support link 7, and both pawls 2, 3 have their respective pivot fulcrums 4 , 13, 17, and 8 are pivotally connected by a connecting pin 9 at a position closer to the other side, and the connecting pin 9 is an isosceles triangle having two rocking fulcrums 4, 13, 17 and 8 as base ends. Of the claw 2 at a position outside the swinging fulcrums 4, 13, and 17 of the one claw 2 and is driven by a hydraulic cylinder through a front pin 11 or a cylinder rod 20 via a drive pin 10. It is characterized by being connected.

[0009]

When the gripping claw device 15 does not require the swinging motion, the pin 4 and the link for pivotally attaching the bucket provided at the tip of the boom 1 of the power shovel are used as the first fulcrum and the second fulcrum. The lever mounting pin 6 is used, or the pin 13 supported by the coupler 31 mounted on the tip of the boom and the link lever mounting pins 6 and 43 are used. Also, if you want the gripping claw to swing,
As the first fulcrum and the second fulcrum, the pins 17 and 18 provided on the swing bracket 16 attached to the tip of the boom are used. In the former case, the front link 11 extending from the bucket swing cylinder of the power shovel is connected to the drive pin 10 provided on the one pawl 2 directly or via the receiving member 36 of the coupler. In the latter case, the front link 11 is connected to the swing bracket 16, and the bucket swing cylinder is used to swing the grip claw device 15, and the cylinder rod of the claw opening / closing cylinder 19 pivotally attached to the swing bracket 16 is used. 20 is connected to the drive pin 10.

When the pawl opening / closing cylinder 19 or the front link 11 connected to the drive pin 10 is moved back and forth, the pawl 2 on the side where the drive pin 10 is provided swings its fulcrum 4, 13, or 1.
Swing around 7. The swinging motion of the one claw 2 is transmitted to the other claw 3 via the connecting pin 9 to swing the claw 3. Since the connecting pin 9 is located at the apex position of the isosceles triangle having the rocking fulcrums 4, 13 or 17 and 8 of the two claws 2 and 3 as the base ends, the two claws 2 and 3 are substantially formed. Since the claws 2 and 3 are rocked at the same rocking angle and the claws 2 and 3 are opened and closed substantially symmetrically, the force balance and the operability are improved.

When the swing angle of the claws 2 and 3 is θ, the distance between the swing fulcrums 4, 13 or 17 and 8 of both claws changes as a function of cos θ. Swing support link 7
Is absorbed by the rocking of. When the pawls 2 and 3 are located at an intermediate position between the closed position and the fully open position, the connection pin 9 is connected so as to be on a straight line between the swing fulcrums 4, 13 or 17 and 8 of both the pawls. If the position of the pin 9 is determined, the swing amount of the swing support link 7 can be minimized, and the opening / closing force of the claws 2 and 3 is most efficiently transmitted from one claw 2 to the other claw 3.

[0012]

1 and 2 show a first embodiment of the present invention, in which a gripper device is directly attached to a boom 1 of a power shovel. In this embodiment, the upper claw 2 of the pair of claws 2, 3 is pivotally attached by the bucket pivot pin 4 at the tip of the boom 1, and the lower claw 3 is based on the pin 6 for mounting the link lever 5. It is pivotally supported by a pin 8 at the tip of a swing support link 7 whose end is pivotally supported. That is, the swinging fulcrum of the upper claw 2 is the bucket pivot pin 4 in the fixed position, and the swinging fulcrum of the lower claw 3 is the pin 8 at the tip of the swing support link 7. Connecting pin holes are provided inside the swinging fulcrums 4, 8 of the upper and lower claws 2, 3 respectively, that is, on the side closer to the swinging fulcrum of the mating claw, and the connecting pin 9 penetrating the both connecting pin holes causes the upper part to move upward. The claw 2 and the lower claw 3 are connected to each other inside the base end thereof. The connecting pin 9 is provided at a position substantially equidistant from the rocking fulcrums 4, 8 of the upper and lower claws, and when the claws 2, 3 are opened, the connecting pin 9 is located on the toe side of the rocking fulcrums 4, 8. The connecting pin 9 is provided so as to be located slightly on the side opposite to the toe side from the swing fulcrums 4, 8 when positioned and closed. By deciding the position of the connecting pin 9 in this way, the opening / closing force is efficiently transmitted from the upper claw 2 to the lower claw 3 at the time of opening / closing the claws described later, and the transmission efficiency of the force on the claw closing side is increased. be able to. A drive pin 10 is provided on the opposite side of the connecting pin 9 with the swinging fulcrum 4 of the upper claw 2 to which a front link 11 for swinging the bucket is pivotally supported. The front end of the front link 11 is pivotally supported at the tip of the link lever 5, and the base end is pivotally connected to the cylinder rod 12 of the bucket rocking cylinder.

When the bucket rocking cylinder is retracted from the claw closed state of FIG. 1, the front link 11 is retracted to the right in the figure, and the upper claw 2 is rotated right about the rocking fulcrum 4. The right rotation of the upper claw 2 moves the connecting pin 9 to the left in the figure, and the lower claw 3 connected thereto is rotated left about the swing fulcrum 8. As a result, the upper and lower claws 2 and 3 are opened. At this time, the line connecting the swinging fulcrum 4 of the upper claw, the center of the connecting pin 9 and the swinging fulcrum of the lower claw goes from the inverted V shape to a straight line state in the figure. Since the swinging fulcrum 4 of the upper claw is a fixed fulcrum, the swinging fulcrum 8 of the lower claw slightly moves up and down by the arc locus of the tip of the swing support link 7.

3 to 6 show the gripper device of the present invention mounted on the boom of a power shovel through a coupler. The coupler 31 is attached to the tip of the boom 1 of the power shovel in order to easily and quickly attach and detach the attachment according to the work, and as shown in FIG. 6, the coupler 31 and the cylinder of the bucket rocking cylinder. Rod 12
From the front link 11 extending from the pins 4, 33
The two receiving members 35 and 36 are pivotally supported by the above, and these receiving members 35 and 36 are provided so as to be relatively movable by a short connecting pin 34, and are urged in the opening direction by a hydraulic cylinder 42 mounted on the receiving member. It is a thing. When mounting the bucket 39 on the coupler 31, the bucket support pins 40, 41
The receiving members 35 and 36 are inserted between the hydraulic cylinder 42 and
Is operated, and the support pins 40 and 41 are fitted and fixed to the receiving portions 37 and 38 of the receiving members 35 and 36. When replacing the bucket 39 at the tip of the boom 1 with the gripping claw device 15 of the present invention, the receiving members 35 and 36 are moved in the direction opposite to the fixing direction to move the receiving portions 37 and 38 and the pins 40 and 41. Disengage,
After removing the bucket, the receiving members 35 and 36 are inserted between the pins 4 and 10 of the gripping pawl device and urged and fixed in the opening direction to fix the pin between the pin 6 of the link lever and the pin 8 of the lower pawl. This is completed by mounting the swing support link 7. As a result, the drive pin 10 of the upper claw is connected to the front link 11 via the receiving member 36 of the coupler.

The grip claw device mounted on the boom 1 via the coupler 31 opens and closes by the same operation as in the above-described embodiment. At this time, the swing fulcrum 13 of the upper claw swings upward with the opening operation of the upper and lower claws 2, 3, so that the bisector of the opening angle of the upper and lower claws 2, 3 moves slightly upward. The direction of the gripper device is tilted upward. In order to avoid such an inclination, as shown in FIG. 5, a pin hole 42 is provided on the base side of the boom 1, and the base end of the swing support link 7 is attached to the pin 4 by the pin hole 42.
By pivotally connecting with 3, the bisector of the open angle can always be maintained in a fixed direction, improving workability.

7 and 8 show a second embodiment of the present invention, in which the grip claw device 15 is attached to the boom 1 of the power shovel through the swing bracket 16. The upper pawl 2 is pivotally attached to the rocking bracket 16 by a pin 17 in a fixed position, and the lower pawl 3 is a rocking support link 7 whose base end is pivotally supported by a cylinder pivot pin 18 provided on the rocking bracket 16. It is pivotally supported by a pin 8 at the tip of the. The insides of the base ends of the upper claw 2 and the lower claw 3 have the same structure as that of the first embodiment and the connecting pin 9
And a drive pin 10 provided on the side opposite to the connecting pin 9 with the pivot point 17 of the upper claw 2 interposed therebetween.
A tip end of a rod 20 of a claw opening / closing cylinder 19 whose base end is pivotally supported by a cylinder pivot support pin 18 is pivotally connected to the. The swinging bracket 16 is swingably pivotally attached to the tip of the boom 1 by a bucket pivoting pin 4 at its lower position, and is pivotally connected to the front link 11 at its upper portion.

Therefore, the swing bracket 1 is moved by moving the bucket swing cylinder provided on the power shovel forward and backward.
6 swings around the bucket pivot pin 4 and causes the grip claw device 15 to perform a swinging motion, and the forward / backward motion of the claw opening / closing cylinder 19 causes the same action as described in the first embodiment to move up and down. The claws 2 and 3 are opened and closed.

[0018]

According to the grasping pawl device of the structure of the present invention described above, the upper and lower pawls can be opened and closed substantially symmetrically, the number of constituent parts is small, and the device can be made compact and lightweight. It has the characteristics that it can be easily attached to the tip, there is little transmission loss of the opening and closing force from the driving side claw to the other side claw, and there is little force applied to the pins and links. Further, since the grasping pawl device of the present invention can be attached to the boom via the coupler, it can be easily attached to and detached from the power shovel.

[Brief description of drawings]

FIG. 1 is a side view showing a closed state of the first embodiment.

FIG. 2 is a side view showing an open state of the first embodiment.

FIG. 3 is a side view of a gripping claw device mounted via a coupler in a closed state.

FIG. 4 is a side view showing an open state of the grip claw device mounted via a coupler.

5 is a modification of FIG.

FIG. 6 is a side view of the coupler.

FIG. 7 is a side view showing a closed state of the second embodiment.

FIG. 8 is a side view showing an open state of the second embodiment.

FIG. 9 is a side view showing a first conventional device.

FIG. 10 is a side view showing a second conventional device.

FIG. 11 is a side view showing a third conventional device.

[Explanation of symbols]

 1 boom 2 upper claw 3 lower claw 4 bucket pivot pin 7 swing support link 8 pin 9 connecting pin 10 swing pin 11 front link 12 cylinder rod 13 pin 15 gripping claw device 16 swing bracket 17 pin 43 pin

Claims (1)

[Claims] 1. A gripping pawl device (15) mounted on the tip of a boom (1) of a power shovel and operated by a hydraulic device of the power shovel, is pivotally supported at a first fulcrum (4, 13, 17). The second fulcrum (6, 4) via the pawl (2) and the swing support link (7).
3,18) and a pawl (3) pivotally supported, and both pawls (2,3) are connected pins at positions closer to the mating side than their swing fulcrums (4,13,17), (8). Pivotally connected by (9), connecting pin (9)
Is located at approximately the apex position of an isosceles triangle with the two rocking fulcrums (4, 13, 17), (8) at the bottom ends, and one claw (2)
It is characterized in that it is drive-connected via a drive pin (10) to a front link (11) or a cylinder rod (20) that is driven forward and backward by a hydraulic cylinder at a position outside the swing fulcrum (4, 13, 17) of The gripping device for a power shovel.