JPH0324678Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a work equipment boom used for a work equipment of a construction machine such as a shovel loader.

Conventional technology Conventionally, the 7th work machine boom for this type of construction machinery was used.
What is shown in FIG. 8 and FIG. 8 is publicly known. The above-mentioned work equipment boom has a structure in which a bucket f is provided at the tip of a boom body b that can be raised and lowered freely by a boom cylinder a, and a bucket f that can be freely rotated by a bucket cylinder c via a bell crank d and a link e. is the pivot part g protruding from the bottom surface of the boom body b.
A yoke h at the tip of the boom cylinder a is pivotally attached to the boom cylinder a by a pin i, and in the latter case, a bracket j is fixed to both sides of the boom body b so that the pivot part g projects downward. The tip of the boom cylinder a is pivotally attached to the pivot part g, and the bending strength of the boom body b is determined by the distance l from the pivot part g to the upper surface.

Problems to be Solved by the Invention For this reason, in conventional work equipment booms, when a certain level of strength is secured, the boom body b becomes taller, resulting in poor visibility over the back of the boom body b when working. It was hot.

This invention was made for the purpose of improving the above-mentioned drawbacks.

Means and action for solving the problem A substantially semicircular notch is formed at the pivot point between the boom body and the boom cylinder, a pivot member is fitted into this notch, and the two are welded together. A work equipment boom for construction machinery in which the pivot member serves as a strength member of the boom body and bears part of the strength of the boom body.

Embodiment This invention will be described in detail with reference to an embodiment shown in the drawings. In the figure, 1 is a body of a construction machine such as a shovel loader, and a working machine 2 is attached to the front part. The work equipment 2 has a structure in which a bucket belt 8 that can be freely rotated by a bucket cylinder 5 via a bell crank 6 and a link 7 is attached to the tip of a boom body 4 that can be raised and lowered by a boom cylinder 3. is structured as follows.

That is, the boom main body 4 is entirely formed of a steel plate or the like, and the pivot portion with the tip of the boom cylinder 3 is cut out into a substantially semicircular shape, and the pivot member 10 is welded to this cutout portion 4a. The welded part of the pivot member 10 to the boom body 4 is formed to have approximately the same thickness as the thickness t of the boom body 4, and the lower part is branched into two paths.
The thickness _t1 of 0a is approximately 1/2 of the thickness t of the boom body 4. Further, the entire structure is made of casting, and a pin hole 10b into which a pin 9 for pivotally connecting the tip of the boom cylinder 3 is inserted is bored in the branching part 10a, and a part of the bending strength of the boom body 4 is In order to carry the hem 10 of the branch 10a
c projects toward the lower surface of the boom body 4, and this protrusion 10d and the lower surface of the boom body 4 are also welded as shown in FIGS. 5 and 6.

Effects of the invention As detailed above, this invention
Since the pivot member 10 to which the tip of the boom cylinder 3 is pivotally attached is used as a strength member of the boom body 4 and bears a part of the strength of the boom body 4, the distance l' of the boom body is shorter than that of the conventional one with the same strength. It can be made smaller than the work equipment boom, which improves the visibility beyond the back of the boom body 4, improving work efficiency, and since the pivot member 10 does not protrude below the boom body 4, the boom Visibility toward the bottom of the main body 4 is also improved.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, in which Fig. 1 is a side view of the construction machine, Fig. 2 is a side view of the work equipment boom, Fig. 3 is a sectional view taken along the line of Fig. 2, and Fig. 4 is a side view of the construction machine.
The figure is an enlarged view of the circle in Figure 2, and Figure 5 is an enlarged view of the circle in Figure 4.
6 is a cross-sectional view taken along the line of FIG. 4, FIGS. 7 and 8 are explanatory diagrams of the conventional art, FIG. 9 is a cross-sectional view taken along the line of FIG. 7, and FIG. FIG. 8 is a sectional view taken along the line of FIG. 3 is a boom cylinder, 4 is a boom body, 4a is a notch, 5 is a bucket cylinder, 6 is a bell crank, 7 is a link, and 10 is a pivot member.

Claims (1)

[Scope of utility model registration request] A bucket belt 8 is provided at the tip of a boom body 4 that can be raised and lowered freely by a boom cylinder 3, and can be rotated by a bucket cylinder 5 via a bell crank 6 and a link 7. A substantially semicircular notch 4a is formed in the pivot portion of the boom body, a pivot member 10 is fitted into the notch 4a, and the contact portion between the notch 4a and the pivot member 10 is welded. 4 and a pivot member 10 are integrated into a working machine boom for construction machinery.