JPH0812267A - Crane - Google Patents

Abstract

PURPOSE:To eliminate the trouble that a main hook is caught on a truss member of a jib so as to prevent the generation of damage of the jib by forming an arch type main hook passing space, through which the main hook can be passed at the time of standing a tower post and at the time of projecting a jib, in the base end of the jib. CONSTITUTION:A base end 10a of a jib 10, which is provided with an auxiliary hook, is fitted to the tip of a tower post 2, which can be stood and which is provided with a main hook 3, freely to be turned. The jib 10 is fitted to the lower side of the tower post 2 in the condition that the tower post 2 is laid on the ground, and thereafter, the tower post 2 is stood in the condition that the jib 10 is held by the tower post 2, and the jib 10 is turned around the base end 10a so as to be projected. In this crane, an arch type main hook passing space 13, through which the main hook 3 can be passed at the time of standing the tower post 2 and at the time of projecting the jib 10, is formed in the base end 10a of the jib 10. The trouble that the main hook 3 is caught on a truss member of the jib 10 is thereby eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane capable of switching between cargo handling work using a tower post and cargo handling work using a jib.

[0002]

2. Description of the Related Art FIGS. 3 to 6 show an example of a conventional crane called a luffing jib crane, which can switch between a cargo handling work using a tower post and a cargo handling work using a jib. As shown in FIG. 3, a traveling tower 1 is provided with a tower post 2 which can be undulated and swiveled, and a main hook 3 is provided at the tip of the tower post 2 so that the main hook 3 can be hung up. ing.

Further, the base end portion 7a of the jib 7 is attached to the left and right jib foot 4 formed at the tip of the tower post 2 via fulcrum pins 5 and 6 so as to be capable of undulating and detaching. A sub-hook 8 is attached to the tip of the jib 7 so that it can be hung up.

In the above crane, when carrying out cargo handling work using only the tower post 2, the main hook 3 suspended from the tip of the tower post 2 or a bucket (not shown) while the tower post 2 is swung and raised and lowered. It is used for general cargo handling work.

When carrying out cargo handling work using the jib 7, as shown by A in FIG. 3, the tower post in a state in which the base end portion of the traveling device 1 is rotatably pivoted so as to be laid down on the ground. 2, the base end portion 7a of the jib 7 is pivotally attached to the tip of the tower post 2 through the fulcrum pins 5 and 6, and then the jib 7 is held as shown in FIG. 3B. 3 raises the tower post 2 to stand up as shown by C in FIG. 3, and then, as shown by D in FIG. 3, the jib 7 is attached to the fulcrum pins 5, 5 of the base end portion 7a.
6 is used as a fulcrum to rotate to assemble the crane, and then the tower post 2 is swung, raised and lowered, and raised and lowered on the jib 7, while using the auxiliary hook 8 suspended from the tip of the jib 7. I am trying to do the work. According to the crane having the jib 7 as described above, compared with the case of the cargo handling work using only the tower post 2,
Cargo handling work can be performed with a large working radius.

[0006]

However, in the above-mentioned conventional crane, when the jib 7 is provided, the jib 7 is attached to the lower side of the tower post 2 which is laid down on the ground as described above when the jib 7 is assembled. Since the jib 7 is extended after the tower post 2 is erected with the jib 7 held, the tower post 2 is laid down on the ground until it is erected as shown in FIG. Therefore, the main hook 3 is held between the tower post 2 and the jib 7 all the time.

At this time, the normal main hook 3 is hung so that the hook tip 3a faces the tip side of the jib 7 as shown in FIG. 4 during operation. When sandwiched between the tower post 2 and the jib 7 in a narrow space, the main hook 3 is held in a 90 ° twisted state.

For this reason, as shown in C in FIG. 3, when the tower post 2 is rotated so that the jib 7 is extended from the state where the tower post 2 is erected, and the gap between the tower post 2 and the jib 7 starts to open.
Since the main hook 3 held between the tower post 2 and the jib 7 tries to rotate so that the hook tip 3a faces the jib 7 side by its own weight, the main hook 3 forms a truss member 9 which constitutes the jib 7. And so on,
Therefore, there are problems that the jib 7 cannot be extended, or the truss member 9 is damaged by being pulled by a large force.

The present invention has been made in view of the above situation, and the main hook is caught on the truss member of the jib when the crane is assembled so that the tower post is erected and then the jib is extended. The purpose is to prevent things from happening.

[0010]

SUMMARY OF THE INVENTION According to the present invention, there is provided a tower post which is capable of undulating and is equipped with a main hook at the tip thereof so as to be able to be hung, and a base end portion of which is rotatably pivotably attached to the tip of the tower post. It has a jib equipped with a sub-hook that can be hung up at the tip, and after mounting the jib on the lower side of the tower post that has been laid down on the ground, raise the tower post with the jib held, and further raise the jib. In a crane configured to rotate and bulge with the base end as a fulcrum, a gate through which a main hook can freely pass at the base end of the jib when the tower post is raised and the jib is extended. The present invention relates to a crane, characterized in that a main hook passage space having a shape is formed.

[0011]

In the present invention, since the main hook passage space having a gate shape is formed at the base end portion of the jib, the jib is attached to the lower side of the tower post which is laid down on the ground, and the tower is held with the jib held therein. When the crane is assembled by rotating the jib so that the post is erected, the main hook caught near the tip of the tower post is freely suspended in the main hook passage space while suspended vertically. It can pass through, so that the main hook does not get caught on the truss member of the jib.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of the present invention applied to the conventional cranes shown in FIGS. 3 to 6, and those designated by the same reference numerals in the drawings represent the same. .

As shown in FIGS. 1 and 2, the base end portion 10a of the jib 10 which is detachably attached to the tip end of the tower post 2 constituting the crane via the fulcrum pins 5 and 6, Legs 1 pivotally attached to the jib foot 4 provided on the left and right ends of the tower post 2 via fulcrum pins 5 and 6.
1 and 12 are formed, and a portal-shaped main hook passage space 13 having a required size is formed between the leg portions 11 and 12.

The main hook passage space 13 is provided in the main hook 3
The jib 10 underneath the tower post 2 which has been laid down on the ground in a state in which the tower is wound near the tip of the tower post 2.
After attaching the jib 10, the tower post 2 is erected with the jib 10 held, and the main hook 3 is vertically moved during the assembling of the crane in which the jib 10 is rotated so as to be extended with the fulcrum pins 5, 6 as fulcrums. Hold jib 10
The size should not interfere with.

Next, the operation of the above embodiment will be described.

When carrying out a cargo handling operation by a crane having a jib 10 on the lower side, as in FIG. 3, the base end is pivotally attached to the traveling device 1 and the lower side of the tower post 2 is laid down on the ground. , The leg portions 11 and 12 of the base end portion 10a of the jib 10 are attached to the tip end of the tower post 2 through the fulcrum pins 5 and 6, and then the tower post 2 is erected, and the jib 10 is rotated so as to be extended. And assemble the crane.

At this time, the main hook passage space 13 is formed in the base end portion 10a of the jib 10 so as to allow the main hook 3 which is wound up near the tip of the tower post 2 to freely pass therethrough. As shown in FIG. 1, the hook 3 always maintains a state of being hung vertically, so that the main hook 3 is assembled at the time of assembling the crane which raises the tower post 2 and overhangs the jib 10 shown in FIGS. Jib 10
The truss member 9 or the like is not caught at all.

[0019]

As described above, according to the crane of the present invention, since the portal-shaped main hook passage space is formed at the base end portion of the jib, the tower post with the jib attached to the lower side is erected, and When assembling a crane that rotates so that the jib is extended, the main hook always keeps the vertical state and freely passes through the main hook passage space, so that the main hook is caught on the truss member of the jib. Can be prevented and the assembly work of the crane can be performed reliably,
It is possible to achieve an excellent effect such that the danger that the main hook is caught on the truss member of the jib and the jib is damaged can be prevented.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a crane of the present invention.

FIG. 2 is a front view of the jib seen from the direction II-II in FIG.

FIG. 3 is a side view showing an assembled state of an example of a conventional crane.

FIG. 4 is a side view showing a part of FIG. 3 in detail.

FIG. 5 is a side view showing a part of an assembled state of a conventional crane.

FIG. 6 is a front view of the jib seen from the VI-VI direction in FIG.

[Explanation of symbols]

 2 Tower post 3 Main hook 8 Secondary hook 10 Jib 10a Base end 13 Main hook passage space

Claims (1)

[Claims] 1. A tower post that can be undulated and has a main hook that can be hoisted at the tip, and a base end portion that can be hoisted at the tip of the tower post, and a sub-hook that can be hoisted at the tip. After installing the jib on the lower side of the tower post that has been laid down on the ground, raise the tower post with the jib held, and further stretch the jib with the base end as a fulcrum. In a crane configured to be rotated to assemble and to be assembled, a gate-shaped main hook passage space through which a main hook can freely pass when the tower post is erected and the jib is extended is formed at a base end portion of the jib. A crane characterized by what it has done.