JP3366263B2 - Counterweight mounting structure - Google Patents

Description

BACKGROUND OF THE INVENTION [0001] [Technical Field of the Invention The present invention relates to a mounting structure of <br/> Ru counterweight put in aerial, especially small altitude
The present invention relates to a structure suitable for application to a work vehicle . 2. Description of the Related Art In a self-propelled work machine such as an aerial work vehicle or a hydraulic excavator, the center of load of a revolving body including an extendable arm, an articulated arm, and the like is as close as possible to the center of rotation. To do so, a counterweight is attached to the rear of the revolving superstructure. [0003] In a work platform or a small hydraulic excavator, the revolving unit frame is made thinner by using a plate-shaped frame for the revolving unit frame to reduce the size. In the case of using such a plate-like revolving structure, the counterweight is fixed by screwing a bolt that is inserted upward from the lower surface of the revolving structure into a hole of the revolving structure into a screw hole provided in the counterweight. . However, in a structure in which the bottom portion of the counterweight is simply fixed to the revolving structure with bolts, the upper portion of the counterweight swings due to the turning or running of the revolving structure during work, and an excessive force is applied to the bolt. The bolt may be deformed or damaged. In addition, the height and weight of counterweights for balancing these telescopic booms, etc. are increased due to the attachment of a long telescopic boom to the revolving superstructure, and not only bolts but also plate-shaped May also be deformed by the inertia of the counterweight. In Japanese Utility Model Laid-Open Publication No. 63-165351, a counterweight is placed on a steel structure forming a revolving body frame, and the revolving body and the upper portion of the counterweight are connected to each other by a stay to reinforce the revolving body. There is disclosed a counterweight in which the deflection of the counterweight is prevented. [0006] As described above, in the structure in which the bottom of the counterweight is simply fixed to the revolving structure with the bolt, a large diameter is required to withstand the load on the bolt or the like due to the swing of the counterweight. Bolts must be used. Further, there is a problem that the structure in which the revolving structure and the counterweight are connected by the stay cannot be realized unless there is a space for attaching the stay at the front of the counterweight. Further, especially in a small aerial work vehicle , there is no space for installing such a stay, and it is more difficult to realize the stay. [0007] In addition, when the steel frame is used for the revolving frame,
The height of the revolving unit increases, the vehicle body becomes large, and the structure of the revolving unit becomes complicated.Furthermore, it is necessary to provide a groove on the bottom surface of the counterweight for fitting to the mold steel of the revolving unit. Since the structure of the counterweight becomes complicated, there is a problem that the cost increases. The present invention has been made in view of the above-mentioned problems of the prior art, and uses a plate-shaped revolving unit and a space for installing a stay.
It is an object of the present invention to provide a counterweight mounting structure for an aerial work vehicle that can be mounted with a high mounting strength while suppressing deflection of the counterweight even when there is no base . According to the present invention , there is provided a counterweight mounting structure for mounting a counterweight mounted on a rear portion of a revolving unit of an aerial work vehicle , wherein at least the counterweight is mounted on the revolving unit. parts are shaped like a plate, the Cow
A counterweight is mounted on the counterweight mounting portion, and is fixed by a bolt inserted from the lower surface of the counterweight mounting portion.
An extension provided in front of the counterweight adjacent to the counterweight.
The reduced boom mounting bracket, characterized by being fixed by upper and and fixing bracket and bolt the front of the counterweight. As described above, the counterweight is not only fixed by the bolt penetrating the plate-shaped mounting portion of the revolving structure, but also the telescopic boom mounting bra projecting upward from the revolving structure.
By fixing the front and top of the counterweight to the bracket with the fixing bracket and bolt,
The deflection of the counterweight can be suppressed, and an excessive load is prevented from acting on the mounting bolt at the bottom of the counterweight. Further, since it is possible to the upper portion of the counterweight is fixed to the telescopic boom mounting bracket on the swing body, stretch Bed load of such counterweight turning body
It can be borne by the arm mounting bracket . Therefore, the load on the revolving structure due to the load and runout of the counterweight can be reduced, so that it is not necessary to increase the thickness of the revolving structure, and the structure of the revolving structure and the counterweight can be simplified. Since a small diameter can be used, the cost can be reduced. [0012] In addition, in the case of aerial work platforms, telescopic boom mounting
Since the bracket for the revolving structure is provided at the rear of the revolving center of the revolving structure, the bracket is located at a position where the counterweight can be fixed, and the structure is located at the center in the width direction of the revolving structure. It is used as a convenient fixing means for fixing of the sheet. FIG. 1 is an elevation work to which the present invention is applied .
FIG. 2 and FIG. 3 are a plan view and a side view of a revolving structure, respectively, showing an embodiment of a vehicle at various telescopic boom angles and telescopic states. In FIG. 1, 1 is a crawler type (or wheel type) traveling body, 2 is a revolving body installed on the traveling body 1 via a revolving device 3, and 4 is protruded on the revolving body 2.
The telescopic boom is mounted on the telescopic boom mounting bracket 10 by means of a boom cylinder 6 with the boom foot pin 5 as a center. At the end of the telescopic boom 4, a mounting bracket 9
However, it is swingably mounted by a hydraulic device (not shown) which always keeps the work table 8 horizontal. A counterweight 11 is mounted at the rear of the revolving superstructure 2. In FIGS. 2 and 3, at least the mounting portion 2a of the revolving unit 2 for the counterweight 11 has a plate shape, and as shown in FIG. The counterweight 11 is fixed to the revolving superstructure 2 by screwing a bolt 14 into the through hole 13 provided in the counterweight mounting portion 2a. The telescopic boom mounting bracket 10 is
A counterweight is provided in front of the mounting portion 2a of the counterweight 11.
It is provided adjacent to the light 11. As shown in FIGS. 2, 3 and 4B, an L-shaped fixing bracket 15 and bolts 16, 1 are provided between the upper part of the counterweight 11 and the telescopic boom 4.
7 fixed. That is, a bolt 16 inserted into a hole provided in the horizontal portion 15a of the fixing bracket 15
Is screwed into a cap nut 19 embedded in the upper surface of the counterweight 11 to fix the fixing bracket 15 to the counterweight 11 and the back plate 10a of the telescopic boom mounting bracket 10 and the fixing. The counterweight 11 is fixed to the telescopic boom mounting bracket 10 by inserting a bolt 17 into a hole provided in the vertical portion 15b of the bracket 15 and screwing it into a nut 20 on the back surface. As described above, the bottom of the counterweight 11 is attached to the counterweight mounting portion 2a of the revolving unit 2 with the bolt 14
In addition to fixing the counterweight 11, the upper part of the counterweight 11 is fixed to the telescopic boom mounting bracket 10, so that the counterweight 11 is prevented from swinging due to turning of the revolving body 2 and running of the aerial work vehicle. For this reason, the bolt 14 and the plate-shaped mounting portion 2a fixing the bottom of the counterweight 11 are prevented from being deformed or damaged by an overload, and high mounting strength is obtained.
When the counterweight 11 is fixed only by the bottom bolts 14, it is necessary to select a large bolt having a high strength as the bolts 14. The size of the bolt 14 can be reduced. In addition, since the counterweight 11 is attached to the bracket 10 so as to be close to the bracket 10, compared with the conventional structure in which the revolving unit 2 and the upper part of the counterweight 11 are connected via two stays, No space, cow
It can be easily realized even in a small aerial work vehicle having a small space at the front portion of the intermediate weight 11 . The telescopic boom mounting bracket 1
Reference numeral 5 may be a structure which is previously attached to the counterweight 11 or the fixing bracket 10 by welding or the like. In the case of aerial work platforms, telescopic boom mounting bracket 1
0 is provided at the rear of the revolving center S of the revolving unit 2 (see FIG. 1), so that the telescopic boom mounting bracket 10 is located at a position where the counterweight 11 can be fixed, and the telescopic boom mounting bracket is provided. Since the center 10 is located at the center in the width direction of the revolving structure 11, the bracket 11 is used as a fixing means convenient for fixing the counterweight 11, and a reasonable structure can be realized. According to the present invention , at least the counterweight mounting portion of the revolving structure has a plate-like shape, a counterweight is mounted on the mounting portion, and the bolt is inserted from the lower surface of the counterweight mounting portion. It is fixed by the mosquito
The counter weight is located in front of the
To the telescopic boom mounting bracket provided next to
Since the upper part and the front part of the counterweight are fixed with brackets and bolts, the deflection of the counterweight can be suppressed, and an excessive load is prevented from acting on the counterweight mounting bolts and the revolving unit. Deformation and damage can be prevented. Unlike the conventional counterweight fixing structure using a stay, no space is required, and a small space with little space is provided at the front of the counterweight .
It can be easily implemented even for aerial work vehicles . Also, the upper part of the counterweight is a telescopic boot.
Since the revolving unit is fixed to the mounting bracket , the load on the revolving unit is reduced, and a thin plate having a simple structure and a small thickness can be used as the revolving unit. As a result, the structure of the counterweight can be simplified, the size can be reduced, and a bolt having a small diameter can be used on the lower surface of the counterweight. As a result, the cost of the self-propelled working machine can be reduced. Further , since the telescopic boom mounting bracket is provided at a position rearward of the center of rotation of the revolving structure, the bracket is located at a position where the counterweight can be fixed, and the structure is moved in the width direction of the revolving structure. Since it is located at the center, it is used as a convenient fixing means for fixing the counterweight, and a reasonable structure can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of an aerial work vehicle to which the present invention is applied .
FIG. 4 is a side view showing various telescopic boom angles and telescopic states. FIG. 2 is a plan view of the revolving superstructure in the present embodiment. FIG. 3 is a side view of FIG. 2; FIG. 4A is a cross-sectional view illustrating a fixing structure of a bottom portion of a counterweight according to the present embodiment, and FIG. 4B is a perspective view illustrating a fixing structure of an upper portion of the counterweight according to the present embodiment. [Description of Signs] 1: Running body, 2: Revolving body, 2a: Counterweight mounting part, 3: Revolving device, 4: Telescopic boom, 5: Boom foot pin, 6: Boom cylinder, 7: Pin, 8: Work Table,
9: Bracket, 10: Bracket for telescopic boom mounting ,
11: counterweight, 12, 19: cap nut, 1
4, 16, 17: bolt, 15: fixing bracket, 2
0: Nut

Claims (1)

(57) [Claim 1] A mounting structure of a counterweight to be mounted on a rear portion of a revolving structure of an aerial work vehicle , wherein at least a counterweight mounting portion of the revolving structure has a plate shape. A counterweight is mounted on the counterweight mounting portion and fixed by bolts inserted from the lower surface of the counterweight mounting portion, and the counterweight is mounted in front of the counterweight mounting portion.
Brackets for telescopic booms installed next to
DOO, the mounting structure of the counterweight, characterized in that fixed by the upper and and fixing <br/> brackets and bolts the front of the counterweight.