JP2583799Y2 - Backhoe swivel structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relatively small backhoe swivel structure. More specifically, the structure of a hydraulic hose at a support portion of a swing bracket is reduced in size while requiring a simple structure. Related to ensuring the technology.

[0002]

2. Description of the Related Art For example, as shown in Japanese Utility Model Publication No. 58-30848, a loop-shaped standing bracket is fixed to a bottom plate made of a thick plate material, and a support plate fixed to the front of the standing bracket. The swing bracket support part is formed by the swing table and the front part of the swivel base, and the bearing bracket and the bottom plate that protrude laterally from the standing bracket are integrated with the bottom plate via reinforcing ribs, and the pivot joint part of the swing cylinder is formed. Are known to constitute a revolving frame.

[0003]

In the above-described structure, although the swivel table can effectively reinforce a portion requiring particularly high strength, a complicated structure for welding a number of relatively small members such as reinforcing members is required. In addition to the structure, it is necessary to separately arrange the arrangement of hydraulic hose groups from the excavation work equipment to the swivel base, and the connection between the swivel frame and the excavation work equipment is exaggerated for dividing a relatively complicated structure. It seems to be a poorly structured structure and seems to have room for improvement. An object of the present invention is to obtain a swivel base having a simple structure and sufficient strength while including the arrangement of hydraulic hoses.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a bottom plate member provided with a turning support for turning freely with respect to a traveling machine base, and a front projecting portion of the bottom plate member. The swing frame is composed of a base plate having a support for swingably supporting the swing bracket left and right, and left and right vertical walls connecting the base plate and the bottom plate member. One vertical wall is extended to the swing cylinder pivotally mounted pivot formed at the rear of the bottom plate member on the side where the vertical wall is disposed, and excavation work is performed by the left and right vertical walls, the bottom plate member, and the base plate. It is characterized in that a space for arranging a hydraulic hose group extending between the device side and the swivel table side is formed, and that the front edges of the left and right vertical walls are formed in a rearwardly concave shape.

[0005]

According to the above characteristic configuration, the bottom plate member, the base plate, and the left and right vertical walls constitute a swivel frame having a box cross-sectional shape, and include a swivel support portion, a swing bracket support portion, a swing cylinder pivoting support portion, and the like. In particular, it is possible to increase the strength of a portion requiring a sufficient strength. In addition, the hydraulic hose group extending over the swivel table and the excavating work device can be routed through the space between the left and right vertical walls connecting and integrating the base plate and the bottom plate member. There is no need to provide a separate policy configuration.

When the swing bracket is swung so as to point the excavating device obliquely, the hydraulic hose group also bends left and right between the left and right vertical walls, but the front edge of the vertical wall is formed in a rearwardly concave shape. Because of this, the hose group can escape to the recessed portion and be displaced. Therefore, the right and left gaps between the front ends of the left and right vertical walls are reduced as much as possible, so that the necessary strength is easily secured while preventing the hose from being rubbed or bent at the front end of the vertical wall. This makes it possible to reduce the thickness of the vertical wall and reduce the weight of the revolving frame, for example, as compared with a method in which the front end of the vertical wall is formed in a linear shape and the left-right interval is made clear. In addition, while exerting the above-mentioned effects, a revolving frame serving as a basis of the revolving base can be basically configured with a simple structure including a small number of members such as a bottom plate member, a base plate, and right and left vertical walls.

[0007]

[Effects of the Invention] Therefore, by revising the basic design, a revolving frame capable of arranging hydraulic hose groups without taking up space while having a simple structure can be constructed. Could be provided.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a small backhoe, 1 is an excavating work device, 2 is a crawler traveling device, 3 is a traveling machine stand, 4 is a turning table, 5 is a control tower, and 6 is a hood. The excavating work device 1 includes a boom 7, an arm 8, a bucket 9, a boom cylinder 7c, an arm cylinder 8c, and a bucket cylinder 9c.
The swing bracket 10 is attached to the swivel base 4 via a swing bracket 10 so as to be swingable about a vertical axis P.

As shown in FIG. 2 and FIG. 3, the revolving base 4 comprises left and right engine frames 11 and 12 and left and right frame frames 13 and 14 formed by pressing a thin plate into a revolving frame F made of a thick plate. And many other members are attached. The turning frame F forms a pair with a bottom plate member 15 provided with a large hole (corresponding to a turning support portion) 22 for allowing the turning frame F to freely turn with respect to the traveling machine base 3, and a front protruding portion 15 a of the bottom plate member 15. A base plate 16 provided with a support portion 16a for swingably supporting the swing bracket 10 to the right and left, and left and right vertical walls 17 connecting the base plate 16 and the bottom plate member 15;
18. The right and left vertical walls 17 and 18 are arranged so as to have a reduced height behind the base plate 16 and have a substantially C-shape in plan view.
Reference numeral 8 extends around the swing cylinder 10c pivotally mounted on the swing cylinder 10c formed at the right rear portion of the bottom plate member 15 until it is turned to the rear side, thereby increasing the strength.

Each of the cylinders 7c, 8c,
A hydraulic hose group H composed of a supply / discharge hydraulic hose 9c and a service hydraulic hose 9c extends from the inside of the box-shaped boom 7 to the routing space 20 of the swivel base 4. That is,
The left and right vertical walls 17,18, the bottom plate member 15, and the base plate 16 form a hydraulic hose group routing space 20.
Pipes are passed through the entrance 21 between the doors 7 and 18 and the inside of the swing bracket 10, and the left and right vertical walls 17 and 1 are connected.
Eight front edges 17e and 18e are cut into a rearwardly concave arc shape. The hydraulic hose group H is connected to a control valve group B in the control tower 5.

For example, when the swing cylinder 10c is operated to swing the swing bracket 10 to the right, the hydraulic hose group H also bends to the right near the vertical axis P and is slightly displaced to the right as a whole. The hydraulic hose group H is inserted into the arc-cut portion of the front end of the right vertical wall 18 so that the left-right space between the front ends of the left and right vertical walls 17 and 18 is reduced as much as possible.

FIG. 4 shows the structure of the end of the boom cylinder 7c on the side of the swivel table. Reference numeral 23 denotes a cylinder case; 24, a piston rod; 25, a cushion pin;
Reference numeral 7 denotes a bypass which connects the oil supply / discharge passage 26 and the oil chamber 29 via the check valve 28, and reference numeral 30 denotes a throttle. At the cylinder displacement limit, the cushion pin 25 is
The cushion function by the oil lock inserted into the cushion chamber 31 at the tip works.
5 The difference between the outer diameter and the inner diameter of the cushion chamber 31 is reduced to improve the effectiveness. However, this causes a large shock when the cushion pin 25 is pulled out of the cushion chamber 31 due to the extension operation, so that the check valve 2 acting on the extension side is used.
The shock is alleviated by 8 and the diaphragm 30.

In the claims of the utility model registration, reference numerals are written for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is a side view of a backhoe.

FIG. 2 is a plan view showing the structure of the swivel table.

FIG. 3 is a cross-sectional view of a front portion of a revolving frame.

FIG. 4 is a sectional view showing the internal structure of the base end of the boom cylinder.

[Explanation of symbols]

 15 Bottom plate member 15a Front projection 16 Base plate 16a Bearing 17, 18 Vertical wall 17e, 18e Front edge 19 Pivot 22 Swivel support F Swivel frame H Hydraulic hose group

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) E02F 9/00 E02F 3/36

Claims (1)

(57) [Scope of request for utility model registration] 1. A pair of a bottom plate member (15) provided with a turning support portion (22) for turning freely with respect to a traveling machine base, and a front projecting portion (15a) of the bottom plate member (15). A base plate (16) having a support portion (16a) for supporting the swing bracket so as to be able to swing left and right, and left and right vertical walls connecting the base plate (16) and the bottom plate member (15). (17) and (18) constitute a revolving frame (F), and one of the left and right vertical walls (18) is connected to the vertical wall (1).
8) A pivot support (1) for pivoting a swing cylinder formed on the rear portion of the bottom plate member (15) on the side where the bottom plate member (15) is disposed.
9) and the left and right vertical walls (17),
(18), the bottom plate member (15), and the base plate (1).
6) form a space for routing the hydraulic hose group (H) over the excavation work device side and the swivel table side, and furthermore, the front edges (17e) of the left and right vertical walls (17) and (18). ), (18
e) A backhoe swivel structure in which e) is formed in a concave shape facing backward.