JPH0240111Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention is an invention concerning the attachment position and shape of the upper and lower boom boss plates, which are provided on the boom of a bomb hoe and serve as supporting parts of the cylinder.

(B) Prior Art Conventionally, in the boom of a bomb hoe, it is known that an upper boom boss plate is disposed above the boom upper plate and a lower boom boss plate is disposed below the boom lower plate.

For example, there is a technique described in Japanese Utility Model Application Publication No. 49-55803.

(c) Problems to be solved by the invention However, in the above conventional technology, the upper boom boss plate and the lower boom boss plate were arranged inside the boom side plate, so the upper and lower boom boss plates were separated from the boom side plate. As a result, the boom upper plate and lower boom plate portions of the boom were not strong enough.

Therefore, there was a problem in that the boom, which was configured in a square shape by the boom side plate, the boom upper plate, and the boom lower plate, was dented at the part where the upper boom boss plate and the lower boom boss plate were fixed.

Conventionally, in order to solve this problem, the boom was composed of a boom side plate, a boom upper plate, and a boom lower plate.
A reinforcing member in the shape of an x was inserted inside to strengthen the structure.

The present invention is constructed so that the strength of the cross-shaped boom can be maintained without inserting a reinforcing member configured in the cross-shape as in the past.

In addition, a conventional technique as described in Japanese Utility Model Application Publication No. 57-187850 is also known, but in this technique, a boom lower plate is attached to the bottom part of the boom side plate and the boom upper plate, which are integrally constructed. Since the structure is fixed by welding, it was not possible to arrange the upper boom boss plate and the lower boom boss plate in an extended state directly below or above the boom side plates.

Furthermore, no technology has been disclosed in the past in which an upper boom boss plate and a lower boom boss plate are provided on an extension of the boom side plates at the ">" shaped bent portion of the boom.

(d) Means for solving the problem The purpose of the present invention is as described above. Next, the configuration for achieving the purpose will be explained.

A front cross-sectional view of the boom 6 of the Batshoe,
The left and right boom boss plates 12L, 12R have a shape in which the boom upper plate 6a and the boom lower plate 6b are fixedly attached to the upper and lower sides of the left and right boom side plates 6L, 6R, and the left and right upper boom boss plates 12L, 12R pivotally support the base 13a of the arm cylinder 13.
is the upper surface of the boom upper plate 6a of the “>” shaped bent portion of the boom 6 in side view, and the boom side plate 6L,
6R, the left and right lower boom boss plates 9L, 9R, which are erected along the boom side plates 6L, 6R and pivotally support the piston tip 10a of the boom cylinder 10, are attached to the ">" shaped bent part. It is erected along the boom side plates 6L, 6R at a position substantially directly below the boom side plates 6L, 6R on the lower surface of the boom lower plate 6b.

(E) Embodiment The purpose and structure of the present invention are as described above. Next, the structure of the embodiment shown in the attached drawings will be explained.

Fig. 1 is an overall side view of the backhoe, Fig. 2 is an overall perspective view of the backhoe, Fig. 3 is an overall side view of the boom, Fig. 4 is a front sectional view of a conventional boom, and Fig. 5 is an overall side view of the backhoe.
The figure is a front sectional view of the boom of the present invention, Figure 6 is an enlarged side view of the conventional upper boom boss plate, and Figure 7 is the 6th
8 is an enlarged side view of a conventional lower boom boss plate, FIG. 9 is a front sectional view of FIG. 8,
Fig. 10 is a side view of the boom of the present invention, Fig. 11 is a front sectional view of Fig. 10, Fig. 12 is an enlarged side view of the lower boom boss plate of the invention, and Fig. 13 is a front sectional view of Fig. 12. It is.

As shown in FIGS. 1, 2, and 3, the backhoe has an engine room 2 and a driver's cab 3 mounted on a chassis 5 on a crawler 1. In addition, a boom support part 4 for pivotally mounting a boom 6 is attached to the center of the front end of the chassis 5, and the boom 6 and the boom support part 4 are connected by a pivot pin 18 so that the boom 6 can move up and down. It is pivotally supported.

Lower boom boss plate 9 located at the lower center of the boom 6
The boom 6 moves up and down by a boom cylinder 10 interposed between L and 9R and the boom support section 4.

Further, the rear end of an arm 7 is pivotally attached to the tip of the boom 6, and the rear end 7a of the arm 7 and the upper boom boss plate 12L located at the upper center of the boom 6,
The arm 7 is rotated by the arm cylinder 13 interposed between the arms 12R and 12R.

The rear part of a bucket belt 8 is pivotally attached to the tip of the arm 7, and a bucket cylinder 14 is interposed between the rear part of the bucket belt 8 and the rear part of the arm 7.
The bucket 8 rotates.

By operating each of these cylinders 10, 13, 14 with the operating lever in the driver's cab 3,
By operating the bucket 8, it is possible to do work such as digging.

Furthermore, the space between the crawler 1 and the chassis 5 on the crawler 1 is configured to rotate, so that the boom 6 and bucket cart 8 can be rotated left and right. 15 is an angle blade for doing work such as leveling the ground.

Among these, the boom 6 has a ">" shape when viewed from the side.
It has a bent configuration, with left and right boom side plates 6L, 6R, a boom upper plate 6a, and a boom lower plate 6b.
It is constructed in a front cross-sectional view.

That is, left and right boom side plates 6L and 6R are fixed between the boom upper plate 6a and the boom lower plate 6b,
Its cross section is square-shaped.

The upper boom boss plates 12L and 12R are attached to the boom upper plate 6a surface of the “>” shaped bent portion of the boom 6, and the lower boom boss plates 9L and 9R are similarly attached to the boom lower plate of the “>” shaped bent portion of the boom 6. 6b, respectively.

Conventionally, the upper boom boss plates 12L, 12
R, the mounting position of the lower boom boss plates 9L and 9R is as follows:
Boom side plates 6L and 6R as shown in Fig. 4, respectively.
In other words, they were provided at a narrower interval than the gap between the two, that is, m>n.

In contrast, the present invention has upper boom boss plates 12L, 12R, lower boom boss plate 9, as shown in FIG.
The mounting positions of L and 9R are erected along the boom side plates 6L and 6R, substantially directly above and below the boom side plates 6L and 6R.

That is, the upper boom boss plates 12L, 12R and the lower boom boss plates 9L, 9 face each other.
The distance R is the same as the distance between the boom side plates 6L and 6R, that is, m=n. 16 and 17 are pivot pins.

In the prior art, the configuration of the portion shown in FIG. 4 was configured as shown in FIGS. 6 to 9.

Forces in the longitudinal and vertical directions are applied to the upper boss plates 12L, 12R and the lower boom boss plates 9L, 9R by each cylinder.

However, the boom upper plate 6 that supports the upper boom boss plates 12L, 12R and the lower boom boss plates 9L, 9R
A and the boom lower plate 6b have a large allowable stress in the front-back direction, but are not very strong against bending force in the left-right direction.

On the other hand, the boom side plates 6L and 6R have a large allowable stress in both the vertical direction and the horizontal direction.

Therefore, it is most desirable that the upper boom boss plates 12L, 12R are provided substantially vertically above the boom side plates 6L, 6R of the boom upper plate 6a, and the lower boom boss plates 9L, 9R are provided substantially vertically below the boom lower plate 6b. This is most desirable.

Taking these points into consideration, the present invention has been developed with upper boom boss plates 12L and 12 as shown in FIGS. 10 and 11.
R is a position approximately directly above the boom side plates 6L and 6R of the boom upper plate 6a, which has the strongest strength;
It is erected along the boom side plates 6L and 6R, and has a structure that has durability in both the vertical and horizontal directions.

Also, in the shape of the boom 6 itself, ">"
Since it is bent in a shape, the ">" shaped bent part is the strongest part, and the upper boom boss plates 12L, 12R and the lower boom boss plate 9 are attached to this part.
By arranging L and 9R, these strengths can be enhanced.

Similarly, the lower boom boss plates 9L and 9R are also
As shown in the figure and FIG. 13, the boom lower plate 6b of the strongest ">" shaped bent part of the boom 6 is provided almost directly below the lower boom boss plates 9L and 9R, and is erected along the boom side plates 6L and 6R. and boom side plate 6L,
It has a structure in which force is applied directly to 6R, and is designed to solve the problem of the boom upper plate 6a and boom lower plate 6b bending or denting in the left and right direction, which was a weak point in the past. be.

(f) Effects of the invention Since the invention is constructed as described above, it has the following effects.

Firstly, the arm cylinder 1 By expanding the boom cylinder 10, the load applied to the boom 6 can be supported in the strong portion, and the boom 6 has high durability.

Second, the strength of the square-shaped boom 6, which is composed of the boom upper plate 6a, the boom lower plate 6b, and the boom side plates 6L and 6R, with respect to the arm cylinder 13 and the boom cylinder 10 can be increased without providing a reinforcing member inside. We were able to improve the number of parts while maintaining the same number of parts.

Thirdly, in the past, there was a problem in which the boom upper plate 6a and the boom lower plate 6b of the boom 6, which was configured in a square shape, were dented due to the horizontal force applied to the cylinder. By configuring, the boom side plate 6L placed inside the
Since 6R acts as a reinforcing material for the boom upper plate 6a and boom lower plate 6b, it is possible to eliminate dents caused by bending loads in the boom upper plate 6a and boom lower plate 6b.

[Brief explanation of the drawing]

Fig. 1 is an overall side view of the backhoe, Fig. 2 is an overall perspective view of the backhoe, Fig. 3 is an overall side view of the boom, Fig. 4 is a front sectional view of a conventional boom, and Fig. 5 is an overall side view of the backhoe.
Figure 6 is a front sectional view of the boom of the present invention, Figure 6 is an enlarged side view of a conventional upper boom boss plate, Figure 7 is a front sectional view of Figure 6, and Figure 8 is an enlarged side view of a conventional lower boom boss plate. , FIG. 9 is a front sectional view of FIG. 8, FIG. 10 is an enlarged side view of the upper boom boss plate of the present invention, FIG. 11 is a front sectional view of FIG.
Figure 2 is an enlarged side view of the lower boom boss plate of the present invention;
FIG. 13 is a front sectional view of FIG. 12. 6...Boom, 6a...Boom upper plate, 6b...
Boom lower plate, 6L, 6R...Left and right boom side plates, 9
L, 9R...Left and right lower boom boss plate, 10...Boom cylinder, 10a...Piston tip, 1
2L, 12R...Left and right upper boom boss plate, 13...
...Arm cylinder, 13a...Arm cylinder base.

Claims (1)

[Scope of utility model registration request] A front cross-sectional view of the boom 6 of the Batshoe,
The left and right boom boss plates 12L, 12R have a shape in which the boom upper plate 6a and the boom lower plate 6b are fixedly attached to the upper and lower sides of the left and right boom side plates 6L, 6R, and the left and right upper boom boss plates 12L, 12R pivotally support the base 13a of the arm cylinder 13.
is the upper surface of the boom upper plate 6a of the “>” shaped bent portion of the boom 6 in side view, and the boom side plate 6L,
6R, the left and right lower boom boss plates 9L, 9R, which are erected along the boom side plates 6L, 6R and pivotally support the piston tip 10a of the boom cylinder 10, are attached to the ">" shaped bent part. A cylinder support structure for a backhoe boom, characterized in that it is erected along the boom side plates 6L, 6R at a position substantially directly below the boom side plates 6L, 6R on the lower surface of the boom lower plate 6b.