JPH05140964A - Counterweight attachment / detachment equipment for construction machinery - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an inexpensive attachment / detachment device that allows safe and quick attachment / detachment of a counterweight by a hydraulic cylinder, and requires almost no modification other than the counterweight. [Structure] Holes 3a penetrating up and down and recesses 3b that hang from the holes and open at the bottom surface are provided at a plurality of positions of the counterweight 2, and hydraulic cylinders 8 are respectively held and fixed in the holes 3a. At the lower end of the piston rod 8b of the hydraulic cylinder 8, the recess 3b is formed when the hydraulic cylinder 8 is in the shortest state.
Attach the grounding plate 11 that fits in. Counterweight 2
Is connected to the body of a hydraulic excavator or the like with a removable connecting tool. When the counterweight 2 is removed, the hydraulic cylinder 8 is extended to ground the ground plate 11, the counterweight is disconnected from the main body, and then the hydraulic cylinder is shortened to lower the counterweight to the ground.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an attaching / detaching device for attaching / detaching a cowta weight to / from a rear end portion of a main body of a construction machine such as a hydraulic excavator by itself.

[0002]

2. Description of the Related Art Currently, a counterweight attaching / detaching device for a hydraulic excavator is put into practical use, which is a model of Japanese Utility Model No. 61.
There are the following two as described in JP-A-38863. That is, as one of them, as shown in FIG. 5, a sheave 53 is provided on the upper rear side of the shovel body 52, and a hook 55 and a counterweight 5 attached to the upper plate of the boom 54 are provided.
1 is connected to the sheave 53 by a wire rope 56, and the counterweight 51 is moved by raising and lowering the boom 54.
To move up and down. In the other, as shown in FIG. 6, the counterweight 61 is connected to the shovel body 65 via the adjuster 62 and the two links of the second link 63 and the first link 64, and the shovel body 65 and the first link are connected to each other. The counterweight 61 is moved up and down by the expansion and contraction of the hydraulic cylinder 66 connected to the link 64.

[0003]

In the former attaching / detaching device,
Each time the counterweight 51 is attached or detached, the wire rope 56
Must be installed and removed, which is troublesome and requires an operator to climb on the back of the boom 54, which is dangerous. Further, when the counterweight 51 is moved up and down, the counterweight 51 may be hooked on the shovel body 52 to deform the shovel body 52 or break the wire rope 56. further,
It is necessary to modify the sheave 53 to the shovel body 52 and the hook 55 to the upper plate of the boom 54.

In the latter attachment / detachment device, a bracket 67 supporting the hydraulic cylinder 66 and a bracket 68 supporting the first link 64 are attached to the shovel body 65, and a strong welding structure is required in order to cope with a strong cylinder force. , It is extremely difficult to add it to the assembled machine later. Further, since the counterweight 61 is moved up and down via the link mechanism, high-pressure oil in the main circuit must be used, and it is necessary to remodel the hydraulic circuit by adding a pilot valve and pilot circuit for operating the high-pressure oil. .. Furthermore, the hydraulic cylinder 66 is expensive, the link mechanism is complicated, the number of parts is large, and the parts cost and the assembly cost are high. In addition, a large space for accommodating the hydraulic cylinder 66, the links 64, 63 and the like is required inside the counterweight 61, and it is difficult to obtain a desired weight of the counterweight.

The present invention has been made in view of these problems, and the counterweight can be attached and detached safely and quickly by a hydraulic cylinder, and the attachment and detachment is inexpensive and requires almost no modification other than the counterweight. The purpose is to provide a device.

[0006]

In order to achieve the above object, the counterweight attaching / detaching device of the present invention is provided with a plurality of holes in the counterweight, which are provided with vertically penetrating holes and recesses which are connected to the holes and open to the bottom. , Fixing hydraulic cylinders in the holes respectively, and at the lower end of the piston rod of the hydraulic cylinder, attach a ground plate that fits in the recess of the counterweight in the shortest state of the hydraulic cylinder, and attach the counterweight to the main body of the construction machine. It is characterized in that it is configured to be coupled by a detachable connector.

[0007]

When the counterweight is removed, the hydraulic cylinder is extended to ground the ground plate of the piston rod, the counterweight is disconnected from the body of the construction machine, and then the hydraulic cylinder is shortened. Down to the ground. To attach the counter weight, reverse the procedure.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be described.

As shown in FIG. 3, at the left and right end portions and the intermediate portion of the counterweight 2 having a can box structure attached to the hydraulic excavator main body (swinging body) 1, holes 3a penetrating vertically and its holes are formed, respectively. A vertical pipe body 3 having a recessed portion 3b that hangs on 3a and opens at the bottom face is fixed by welding, and in the front-rear direction inside, as shown in FIG. The rod 6 protruding toward the main body 1 is fixed. The inside of the counterweight 2 is filled with a pawl 7 such as heavy concrete.

As shown in FIG. 3, a hydraulic cylinder 8 having a flange 8a at its lower end is inserted into the hole 3a.
The flange 8a is fastened with a bolt 10 to a flange 9 integrally provided at the lower end of the hole 3a of the vertical tube body 3. A circular ground plate 11 is attached to the tip (lower end) of the piston rod 8b of the hydraulic cylinder 8. As shown in FIG. 4, the tip of the mounting bolt 4 inserted into the lateral tube body 5 is fastened to the main body 1 by the nut 12, and the protruding portion of the rod 6 is fitted into the hole 1 a of the main body 1. On the end face of the protruding portion of the rod 6, a stopper plate 1 for preventing the protruding portion from coming off
3 is fixed by a bolt 14. The diameter of the hole 1a is set larger than the diameter of the protruding portion of the rod 6. When the counterweight 2 is attached, the protruding portion of the rod 6 bears the weight of the counterweight 2.

The operation valve (direction switching valve) 15 shown in FIGS. 1 and 2 is connected to a pilot hydraulic pressure take-out port 18A and a return port 18B provided in the main body 1 by a hose 16 and is connected to each hydraulic cylinder 8. It is connected by a hose 17. The operation valve 15 is operated to extend / contract the hydraulic cylinder 8. The operation valve 15 is installed near the left end of the counterweight 2 so that it can be operated from the catwalk 19, which is a passage normally provided only on the cab side, or from the crawler belt.

When the counterweight 2 is connected to the main body 1, the ground plate 11 of the hydraulic cylinder 8 is housed in the recess 3b as shown in FIG. This prevents deformation and damage of the hydraulic cylinder 8 during work.

When removing the counterweight 2, first, the stopper plate 13 is removed and the mounting bolt 4 is loosened slightly. Next, the operation valve 15 extends the hydraulic cylinder 8 to bring the ground plate 11 into contact with the ground. Further, when the slightly hydraulic cylinder 8 is extended, a play is generated between the protruding portion of the rod 6 and the hole 1a of the main body 1. In this state, the mounting bolt 4 is removed, and the main body 1 is advanced until the protruding portion of the rod 6 comes off the hole 1a. After that, the hydraulic cylinder 8 is shortened by the operation valve 15, and the counterweight 2 is lowered to the ground as shown by the chain line in FIG.
Finally, the hose 16 is cut off at the hydraulic outlet 18A and the return outlet 18B of the main body 1 to complete the removal of the counterweight 2. Hydraulic outlet 18A, return 18B
If is a quick coupler, there is no oil leakage, and connection and disconnection can be performed with one operation.

The counterweight 2 can be attached by performing the reverse operation to the above.

[0015]

According to the present invention described above, the counterweight can be attached and detached quickly and safely, and no modification of the main body is required except for providing a pilot hydraulic pressure take-out port and a return port. Further, since the pilot pressure oil can be used to operate a plurality of hydraulic cylinders to raise and lower the counterweight without using a link mechanism, the cost can be reduced as compared with the conventional hydraulic cylinder type. Furthermore, since a large space is not required inside the counterweight, it is easy to secure the weight.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention,

2 is an enlarged plan view showing a part of the main body of the counterweight and the hydraulic excavator of FIG.

FIG. 3 is a sectional side view showing a mounting structure of the hydraulic cylinder in FIGS. 1 and 2;

FIG. 4 is a sectional side view showing a connecting structure of the counterweight shown in FIGS. 1 and 2 to the shovel body;

FIG. 5 is a side view showing a hydraulic excavator including a conventional counterweight attaching / detaching device using a wire rope;

FIG. 6 is a side view showing a conventional counterweight attaching / detaching device using a hydraulic cylinder.

[Explanation of symbols]

 1 Main body of hydraulic excavator 1a Hole 2 Counterweight 3 Vertical tube 3a Hole 3b Recess 4 Mounting bolt 5 Horizontal tube 6 Rod 8 Hydraulic cylinder 8b Piston rod 9 Flange 10 Bolt 11 Ground plate 12 Nut 13 Stopper plate 14 Bolt 15 Operation valve 16 hoses 17 hoses

Claims (1)

[Claims] 1. A counterweight is provided at a plurality of positions with holes penetrating vertically and recesses which are connected to the holes and open on a bottom surface, and hydraulic cylinders are respectively held in the holes to fix the holes to a lower end of a piston rod of a hydraulic cylinder. The construction machine counter is characterized in that a grounding plate that fits in the recess of the counterweight in the most shortened state of the hydraulic cylinder is attached, and the counterweight is connected to the main body of the construction machine by a detachable connector. Weight attaching / detaching device.