JPH07158116A - Counterweight of construction machinery - Google Patents

Abstract

PURPOSE:To make it possible to change weight, etc., without changing an outward appearance of a counterweight provided to a construction machinery such as a hydraulic shovel, etc. CONSTITUTION:A counterweight 10 is constituted of a counterweight main body 11 and a variable heavyweight matter 20, a recessed section 15 is formed in the upper face plate 12c of the counterweight main body 11, and the variable heavyweight matter 20 is loaded to the recessed section 15 in a detachable manner. The variable heavy weight matter 20 is so formed that a housing 21 is filled with a filling matter 22, the filling matter 22 is constituted of the heavyweight matter such as scrap-iron, etc., and cement, and specific bravity can be changed by changing mixing ratio of then. In order to fix the variable heavyweight matter 20 in a state to store it in the recessed section 15, a mounting plate 23 is mounted to the upper part of the variable heavyweight matter 20, and the mounting plate 23 is fixed to a diameter widening section 15a in the recessed section 15 of the counterweight main body 11 with bolts 25. Accordingly, overall weight of the counterweight 10 can be adjusted by exchanging the variable heavyweight matter having different specific gravity to load.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a counterweight mounted on a construction machine such as a hydraulic excavator.

[0002]

2. Description of the Related Art As a construction machine, for example, in a hydraulic excavator, as shown in FIG. 3, an upper revolving structure 2 is rotatably mounted on a lower traveling structure 1, and a front part of the upper revolving structure 2 is mounted. Has a front working mechanism 6 including a boom 3, an arm 4 and a bucket 5. The upper revolving superstructure 2 is provided with a driver's cab 7 in front thereof, an engine, a hydraulic pump, etc. are mounted in a rear portion thereof, and a counterweight 8 is provided in a rearmost position. The counterweight 8 stabilizes the vehicle by balancing the weight of the front work mechanism 6 when the front work mechanism 6 is operating. For this reason, the counterweight 8 having a predetermined weight and a center of gravity is used.

[0003]

By the way, various types of front working mechanism 6 are used depending on the type of work.
For example, when excavating earth and sand, as shown in the figure,
The bucket 5 is used, but when crushing concrete or the like, a crushing claw is attached and it may function as a crane. The configuration of the front work mechanism is changed according to each of these works. When the work according to each mechanism is performed by changing the front work mechanism in this way, from the viewpoint of weight balance, the weight of the counterweight 8 is changed. It is preferable to change However, the weight of the counterweight 8 cannot be adjusted after mounting, regardless of whether the counterweight itself is replaced. For this reason, in the prior art, when the weight is increased, a heavy object such as an iron plate is welded and fixed to the counterweight mounted on the vehicle.

Here, the counterweight has an arcuate shape or a crescent shape in which the rear end surface is curved in a convex shape, and the inner side surface faces a cover member on which an engine or the like is mounted,
The bottom surface is fixed to the body frame. For this reason, two surfaces, the rear end surface and the upper surface, are exposed to the outside. Since the shape of the rear end face influences the turning radius of the upper revolving structure, if a heavy object is welded to the rear end face, the revolving radius of the upper revolving structure becomes large by the amount of protrusion, which is not preferable. . Therefore, the heavy object can be attached only to the upper surface of the counterweight. However, since the counterweight is in the rear view from the driver's cab, if the upper surface of the counterweight is largely projected, the rear view is deteriorated and the appearance is unsightly. In this way, in addition to the problem of the attachment part of the heavy weight in the counterweight, and the problem of the difficulty of the work of fixing it by welding, the weight is adjusted by adding the heavy weight to the counterweight. Not preferred.

In addition, in the method of adding a heavy load,
It is not possible to reduce the counter weight. Here, in order to make it possible to reduce the counterweight,
It is also known that an auxiliary weight is used and the weight is adjusted by appropriately attaching and detaching the auxiliary weight, but in this case, the weight can be adjusted only in two steps of attaching or removing the auxiliary weight. There is a problem that it can not be changed, and if the auxiliary weight is not attached, the counterweight will have a recessed portion, so that the earth and sand will accumulate, so remove this earth and sand before attaching the auxiliary weight. Therefore, there is a drawback that the attachment and detachment work of the auxiliary weight becomes extremely troublesome.

The present invention has been made in view of the above points, and an object of the present invention is to easily and finely adjust the weight according to the front working mechanism without changing the appearance of the counterweight. To be able to adjust to.

[0007]

In order to achieve the above-mentioned object, the present invention mounts a counterweight main body on the rear end of a vehicle body frame of a construction machine, and forms a recess in the counterweight main body. The feature is that variable weight objects having different specific gravities are detachably mounted in the recesses.

[0008]

The weight of the counterweight is determined by the weight of the counterweight body and the weight of the variable weight. A plurality of variable weights having different specific gravities, that is, those having the same outer dimensions but different weights can be appropriately exchanged for attachment / detachment. Here, as the variable weight, a variable weight is used in which a container made of a metal plate is filled with a predetermined filler. Therefore, the specific gravity of the variable weight object can be changed by changing the structure of the filling material. The filling material can be constituted by, for example, a heavy material such as iron scrap and solidifying with cement in order to prevent a gap from being generated inside the container. In this case, the specific gravity of the variable weight as a whole can be changed by changing the mixing ratio of the heavy weight and the cement. Then, a plurality of types of variable weight objects having different specific gravities are prepared.

The variable weight is optimally mounted according to the front working mechanism of the vehicle. For example, when excavating earth and sand, a bucket is attached to the tip of an arm in the front work mechanism to perform the work. During this excavation work, the front work mechanism receives a predetermined load. A variable weight having a predetermined specific gravity is attached to the counterweight in order to have a corresponding weight. On the other hand, attach a hook to the tip of the arm,
When functioning as a crane that lifts heavy objects, it is necessary to make the counterweight heavier than when excavating earth and sand. Therefore, the variable weight object is replaced with a heavier one. When crushing concrete or the like, a crushing claw is attached as a front working mechanism, but the weight of the counterweight may be lighter than that when excavating earth and sand. Therefore, when this crushing claw is used, a lighter weight variable object is attached as compared with the case of excavating earth and sand.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 shows a plane of the counterweight 10, and FIG. 2 shows a cross section thereof. Counterweight 10
Is composed of a counterweight main body 11 and a variable weight 20. The counterweight main body 11 has a box-shaped housing 12 in which a metal plate has a predetermined outer shape, and a filling material 13 is filled in the housing 12. It has been made solid. Here, the filling 13 is formed by cementing a heavy material such as iron scraps with cement. In the housing 12, the rear end face plate 12a is curved in a convex shape, and the inner side face plate 12b has a substantially flat plate shape.
Further, a top plate 12c and a bottom plate 12d are connected to the upper and lower portions of the rear end face plate 12a and the front side face plate 12b, so that the entire counterweight 10 has a substantially arcuate or crescent shape.

The counterweight body 11 has a bottom plate 12d of a housing 12 fixed to the rear end of the vehicle body frame 14 by bolts or the like.
On the other hand, the upper surface plate 12c is not a flat surface, and the recess 15 is formed. The concave portion 15 has a cubic shape having a predetermined depth, and the upper end portion thereof has the enlarged diameter portion 1
5a.

The variable weight object 20 is removably mounted in the recess 15, and the variable weight object 20 is housed in a state where there is almost no gap. Like the counterweight main body 11, the variable weight object 20 is configured by filling the inside of the housing 21 with the filler 22. Here, as the variable weight object 20, those having different specific gravities are used by changing the components of the filler 22.
The filler 22 is composed of a heavy material such as iron scraps and cement, and the weight can be changed by changing the mixing ratio of the iron scraps and the cement without changing the specific gravity, that is, the outer shape. It is like this. Moreover, not only the difference in specific gravity but also the position of the center of gravity can be changed by changing the distribution of iron scrap.

A mounting plate 23 is attached to the upper part of the variable weight 20 in order to fix the variable weight 20 in the recess 15. The mounting plate 23 is fitted into the enlarged diameter portion 15a of the recess 15, and the bolt insertion hole 24 is formed at the peripheral portion of the mounting plate 23, that is, at a position avoiding the mounting portion of the variable weight 20. Further, a screw hole 26 into which a bolt 25 for fixing the variable weight 20 is screwed is formed at a position corresponding to the bolt insertion hole 24 of the enlarged diameter portion 15a in the recess 15. Further, instead of the bolt 25, an eyebolt 27 is attached to the bolt insertion hole 24, and the eyebolt 27 is hoisted by a hoisting machine such as a crane, so that the variable weight 20 can be attached to and detached from the recess 15. . For this reason, the bolt insertion hole 24 is a large-diameter screw hole, and the eyebolt 27 has the bolt insertion hole 24.
It can be screwed into.

The present embodiment is constructed as described above, and the counterweight 10 is mounted on the rear portion of the vehicle body. With this counterweight 10, the front working mechanism is operated when the front working mechanism works. The load received can be balanced to stabilize the vehicle. Here, the counter weight 10 is
The total weight of the counterweight main body 11 and the variable weight 20 mounted on the counterweight main body 11 is obtained.

As the variable weight 20, a plurality of variable weights having the same outer shape but different weights are used. A variable weight 20 having an optimum weight is attached to the counterweight body 11 according to the front working mechanism of the vehicle.
A hydraulic excavator is generally for excavating earth and sand, and at the time of this work, when a bucket is attached to the arm of the front work mechanism, at the time of this excavation work,
Optimal weight counterweight for stabilizing the vehicle 1
The weight of the variable weight 20 is selected so that it becomes zero, and the variable weight 20 is mounted in the recess 15 of the counterweight main body 11 and fixed by the bolt 25.

On the other hand, even in the case of a hydraulic excavator, a hook may be attached to the tip of an arm of the front working mechanism to lift a heavy object, that is, to function as a crane. In this case, since the load supported by the front working mechanism becomes large, the weight of the counterweight 10 must be heavier than when excavating the earth and sand. In this case, an object that is heavier than the variable weight object that is installed during excavation work is installed. To this end, the bolt 25 is removed from the currently mounted variable weight object 20, and the eyebolt 27 is connected to the mounting plate 23 of the variable weight object 20. Then, the variable weight object is lifted and taken out. A variable weight having a necessary weight for performing work is selected and attached to the counterweight 10. In addition to this, when the crushing claw is attached to the arm and the crushing claw is used to crush concrete or the like, the weight of the counterweight 10 may be lighter than when excavating the earth and sand. Therefore, when this crushing claw is used, a counterweight 10 is attached by mounting a lighter weight variable object as compared with the case of excavating earth and sand.
The weight can be adjusted.

As described above, by using the variable weight objects having different weights, the weight of the counter weight can be changed to the optimum one according to the front working mechanism and can be mounted. Further, since the front working mechanism is located away from the center axis of the vehicle, it may be preferable to change not only the weight of the counterweight but also the center of gravity depending on the working mechanism to be mounted. Not only the weight of the object 20 is changed, but also the position of the center of gravity can be changed depending on the position of the heavy object in the filler 22 in the housing 21, so that the position of the center of gravity can be adjusted as necessary. .

As described above, when changing the weight of the counterweight 10 and the like, the variable weight 20 having the same outer shape and variable weight is exchanged. Therefore, the counterweight 10 is changed. There is no need to change the outline of the. Therefore, in the housing 12 of the counterweight 10, the shape of the rear end face plate 12a that influences the turning radius and the shape of the upper face plate 12c and the like necessary to secure the rear visual field do not change, and it is preferable in terms of appearance. Become. In addition, since the variable weight 20 is always attached to the concave portion 15 of the counterweight 10 and the concave portion 15 is not left as it is, sediment is not accumulated and cleaning can be easily performed.

[0019]

As described above, according to the present invention, the counterweight body is formed with the concave portion, and the variable weight objects having different specific gravities are detachably attached to the concave portion.
Depending on the type of work, etc., the weight of the variable weight can be easily adjusted so that the weight of the counterweight is in an optimum state to ensure the stability of the vehicle. When adjusting, there is an effect that it is not necessary to change the outer shape of the counterweight.

[Brief description of drawings]

FIG. 1 is an external view of a counterweight showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is an external view of a hydraulic excavator as an example of a construction machine.

[Explanation of symbols]

 10 Counterweight 11 Counterweight Main Body 15 Recess 15a Expanded Diameter 20 Variable Weight 21 Housing 22 Filling 23 Mounting Plate 24 Bolt Insertion Hole 25 Bolt 27 Eye Bolt

Claims (3)

[Claims] 1. A structure in which a counterweight main body is mounted on a rear end portion of a vehicle body frame of a construction machine, a concave portion is formed in the counterweight main body, and variable weight objects having different specific gravities are detachably mounted in the concave portion. The counterweight of construction machinery that is characterized by 2. The counterweight for a construction machine according to claim 1, wherein the variable weight object is provided with a connecting tool which is engaged with and disengaged from a hoisting mechanism so as to be attached to and detached from the recess. 3. The counterweight for a construction machine according to claim 1, wherein the counterweight of the entire counterweight is changed by mounting the variable weight object.