JP2585792Y2 - Swivel joint mounting structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a structure for mounting a swivel joint mounted on a construction machine such as a hydraulic shovel or a working vehicle.

[0002]

2. Description of the Related Art FIG. 3 is a partially cutaway side view of a lower traveling body 1 of a hydraulic shovel. In the figure, 2 is a lower frame.
3, swivel bearing 4, swivel joint 5,
Is a support plate of the swivel joint 4, 6 and 7 are bolts, 8
Is the center frame of lower frame 2, and 9 is the center frame.
The front and rear standing plates 10 and 10 are the lower plate, the bracket 11 is welded to the standing plate 9, and the reinforcing ribs 12 are provided on the bracket 11. FIG. 4 is a plan view of a main part of the lower traveling body 1 in FIG. FIG. 5 shows the center frame 8 in FIG.
3 is an enlarged perspective view of a portion A of FIG. As shown in FIGS. 3 to 5, a swivel bearing 3 is mounted on the upper part of the lower traveling body 1, and a swivel joint 4 is provided on the axis of the swivel bearing 3. A support plate 5 is attached to the bottom surface of the swivel joint 4 with bolts 6, and the front and rear portions of the support plate 5 are mounted on a bracket 11 welded to the front of the center frame 8 and the rear standing plates 9, 9. It is fixed with bolts 7.

[0003]

[Problem to be Solved by the Invention] When a hydraulic excavator is used, vertical vibrations and impacts are generated in the swivel joint due to the operation of an attachment (not shown) or running on uneven terrain, and the bottom of the swivel joint is generated. Excessive moment load is applied to the center frame side mounting portion via the mounted support plate. However, the conventional mounting portion is formed by welding a plate-shaped bracket to the inner surface of the standing plate of the center frame, inserting a reinforcing rib between the bracket and the lower plate, and welding. However, the thickness of the bracket is thin, and the threaded portion holding the support plate is overhanged from the reinforcing rib. For this reason, cracks may occur in the welded portion between the lower surface of the bracket on which the maximum bending moment acts and the reinforcing rib. Further, since the thickness of the bracket is small and the screw depth is not sufficient, the bolt may be loosened. The purpose of the present invention is to solve the above problems.

[0004]

A lower plate and a lower plate are provided.
A center frame having an upright standing plate;
So that the swivel joint is fixed to the tab frame
In the swiveling construction machine,
A support plate fixed to the bottom of the int;
Thick plate thicker than the support plate attached to the standing plate
And the plank block is in front of the upright.
One side of the thick plate block is in contact with the lower plate, and
Make sure that at least half of the lower surface of the board block touches
Then, when it is welded and attached to the center frame,
The support plate is screwed to the plank block.
This allows the swivel joint to
To be fixed to the

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a partially cutaway side view of a main part of a lower traveling body 13 showing attachment of a swivel joint of the present invention. In the figure, the same reference numerals are given to components using the same components as the conventional technology. 14 is a lower frame, 15
Is a center frame of the lower frame 14, and 16 is a thick plate block. FIG. 2 shows the center frame 15 in FIG.
3 is an enlarged perspective view of a portion B of FIG.

Next, the mounting structure of the swivel joint of the present invention will be described with reference to FIGS. The lower traveling body 13 of the present invention has a swivel joint 4 in which the slewing bearing 3 is mounted on the upper part of the lower frame 14, the shaft center of the slewing bearing 3 near the upper part of the lower frame 14, and the support plate 5 on the bottom part. Is arranged. In addition, the thick plate blocks 1 are provided on the front and rear upper surfaces of the lower plate 10 of the center frame 15 at the front and rear mounting positions of the support plate 5, respectively.
The support plate 5 is attached by bolts 7 while being welded to the inner surfaces of the standing plates 9 and 9.

Next, the operation of the swivel joint mounting structure of the present invention will be described. In the present invention, the thick plate blocks 16 are disposed at the front and rear upper surfaces of the center frame 15 at the front and rear mounting positions of the support plate 5 mounted on the bottom surface of the swivel joint 4, respectively.
It is welded over the entire circumference in contact with the lower plate 10 and the standing plate 9. As described above, the vibration and impact load applied to the swivel joint 4 due to the operation of the attachment and running on uneven terrain act on the screwed portion of the thick plate block 16 via the support plate 5 and bend to the thick plate block 16. Generate moment. However, since the bending strength of the thick plate block 16 is very high and the screw hole depth can be sufficiently obtained, loosening of the mounting bolt can be prevented. Further, the lower plate 10 and the standing plate 9
Since welding is performed over the entire periphery of the contact portion, the welding strength can be increased.

[0008]

According to the prior art, a thin plate bracket is welded to a center frame to provide a reinforcing rib. However, the thickness of the bracket was thin and the screw depth was not sufficient. In the present invention, a thick plate block is used instead of the bracket and the reinforcing rib. As a result, the above-mentioned strength problem with respect to bending load is solved, and the screw depth is sufficiently secured.
Bolt loosening was prevented, and the strength of the weld was improved. Furthermore, cost reduction was achieved by reducing the number of parts. In addition, by preventing distortion of the bracket, loosening of bolts, and cracks in welds,
The seal inside the swivel joint or the sliding part of the inner and outer joints is prevented to prevent oil leakage, and at the same time, to prevent the hydraulic piping joint from being loosened, thereby preventing oil leakage.

[Brief description of the drawings]

FIG. 1 is a partially cut-away side view of a lower traveling body showing a mounting of a swivel joint according to the present invention.

FIG. 2 is an enlarged perspective view of a portion B of the center frame in FIG.

FIG. 3 is a partially cutaway side view of the undercarriage showing attachment of a prior art swivel joint.

FIG. 4 is a plan view of the lower traveling body in FIG.

FIG. 5 is an enlarged perspective view of a portion A of the center frame in FIG. 3;

[Explanation of symbols]

 1,13 Lower traveling body 2,14 Lower frame 3 Slewing bearing 4 Swivel joint 5 Support plate 8,15 Center frame 9 Upright plate 10 Lower plate 11 Bracket 12 Reinforcing rib

Claims (1)

(57) [Scope of request for utility model registration] 1. A lower plate, and a standing plate erected on the lower plate.
A center frame having
The swivel joint is fixed to the upper swing type construction machine, wherein the bottom of the swivel joint is
A support plate fixed to the lower plate and the upright plate.
A thick block that is thicker than the attached support plate.
And the thick plate block is provided on the upright plate.
And one side of the plate is in contact with the lower plate below the thick plate block.
So that at least half of the surface touches
And the support plate is welded to the frame.
Is screwed to the thick plate block,
Swivel joint fixed to the center frame
Mounting structure of the swivel joint, characterized in that it has to be.