JPH0741289A - Guide sheave housing device of crane boom - Google Patents

Abstract

PURPOSE:To provide a guide sheave housing device in which guide sheaves provided on the rear part of the extreme end of a crane boom can be easily held in a low position at transporting a crane. CONSTITUTION:Guide members 5 provided with guide slotted holes 5b in the direction of up and down are fitted on the behind part of the extreme end of a boom, and a guide sheave shaft 6 supported with supporting brackets 8 is inserted into the guide slotted holes 5b. The threaded part of a bolt 10 inserted from the bolt hole of a stopper 8a fixed to the supporting bracket 8 is fitted in the threaded hole of a cylinder body 9 fixed on the flat plate part 5c of the guide member 5. A coil spring 11 is provided between the stopper 8s and the flat plate part 5c. By screwing the bolts 10 in, guide sheaves 2 are brought down together with the supporting brackets 8, and the guide sheave shaft 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile crane in which a revolving structure is rotatably mounted on an endless track type traveling structure, and a boom is attached to the front part of the revolving structure. The present invention relates to a storage device for storing the guided guide sheave in a low position.

[0002]

2. Description of the Related Art FIG. 8 shows an example of a boom of a crawler crane. The boom 1 is attached to a front portion of a revolving structure (not shown) so as to be able to be raised and lowered, and a guide sheave 2 is attached to a rear surface of a tip end thereof and a point sheave 3 is attached to a front surface portion of the front end thereof. The hoisting wire rope 4 fed from the winch installed on the revolving structure is
It is hung on the point sheave 3, and for example, a bucket, a lifting magnet or the like is hung on it.

When the crawler crane is transported by the trailer with the boom 1 lying down in the transportation position, the transportation height is limited. In this transportation posture, the guide sheave 2 is generally at the highest position. To deal with this,
A means for displacing the guide sheave 2 is disclosed.
Japanese Utility Model Application Publication No. 62-5187, which is a first example thereof, discloses that a guide sheave bracket rotatably provided with a guide sheave is detachably attached to a guide sheave attachment portion by a pin, and a boom tip is provided. There is described a device in which a bracket receiver capable of holding a guide sheave bracket removed from a guide sheave mounting portion in a storage position inside a boom tip portion is provided inside the portion. In a utility model application publication No. 1-109090, which is a second example, a pair of left and right inward and outward lugs are attached to the tip of a boom, and a pair of left and right links that support guide sheaves are attached to both lugs. A coupled sheave storage device is described.

[0004]

The above-mentioned first and second conventional examples have a problem that an auxiliary crane or the like must be prepared for the set during storage or during work.

The present invention has been made in view of the above, and the supporting bracket for supporting the guide sheave can be held at any position in the vertical direction so that the transport height can be easily lowered. It is an object of the present invention to provide a guide sheave storage device capable of performing.

[0006]

According to the guide sheave storage device of the present invention, a guide member having a vertically elongated guide hole is attached to a rear surface of a tip of a boom, and a guide sheave shaft supported by a support bracket is provided. A guide slot provided so as to be vertically movable, holding means for holding the support bracket at an arbitrary vertical position with respect to the guide member, and fixing means for fixing the support bracket at a predetermined position of the guide member. Is characterized by.

[0007]

When the crane is transported, the guide sheave shaft is lowered along with the support bracket along the guide elongated hole of the guide member, and the guide sheave is held at a position lower than the position in the working posture by the holding means.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a first embodiment of the present invention will be described with reference to FIGS. In those figures, 1 to 4
Indicates the same as or equivalent to FIG.

A guide member 5 having an L-shaped cross section is attached to the mounting portion of the guide sheave 2 of the boom 1, and the vertical plate portion 5a thereof has guide slots 5b whose upper and lower ends are semicircular. Is provided. A plurality of, for example, three guide sheaves 2 are rotatably attached to the guide sheave shaft 6 via bearings 7, respectively.
Is pierced through the elongated guide hole 5b of the guide member 5 and is supported by a disc-shaped support bracket 8 which is abutted against the outer surface of the vertical plate portion 5a.

A stopper 8a protruding outward is fixed to the support bracket 8, and the flat plate portion 5 of the guide member 5 is fixed.
A cylindrical body 9 having a screw hole is fixed to c. The threaded portion of the bolt 10 penetrating the bolt hole provided in the stopper 8 a is fitted into the threaded hole of the cylindrical body 9. A coil spring 11 is installed between the stopper 8a and the flat plate portion 5c around the cylindrical body 9. The flat plate portion 5c is provided with a hole that matches the screw hole of the cylindrical body 9. Coil spring 11
Is set so that the support bracket 8 is located at the mounting position of the guide member 5 with respect to the vertical plate portion 5a by the weight of the guide sheave 2, the guide sheave shaft 6, the bearing 7, and the support bracket 8. At the time of work, the support bracket 8 is at that position, and is fixed to the vertical plate portion 5a by the bolt 12 as shown in FIGS. That is, the support bracket 8 is provided with a bolt hole, and the vertical plate portion 5a is provided with a screw hole 5d into which the bolt 11 is screwed.

When the boom 1 is in the transportation posture, the bolt 12 is removed and the bolt 10 is tightened. Then, the coil spring 11 is compressed, and the guide sheave 2 is lowered together with the support bracket 8 and the guide sheave shaft 6. The position of the support bracket 8 can be arbitrarily changed by tightening the bolt 10 within a range in which the coil spring 11 closely contacts or the guide sheave shaft 6 contacts the lower end of the elongated guide hole 5b.

When the guide sheave 2 is in the working posture,
Loosen the bolt 10. Thereby, the support bracket 8 and the guide sheave shaft 6 are driven by the spring force of the coil spring 11.
At the same time, the guide sheave 2 is pushed up. The guide sheave shaft 6 slides in the guide elongated hole 5b.

FIGS. 5 to 7 show a second embodiment of the present invention in which the holding means of the support bracket 8 can be removed, and the same or corresponding constituent elements as those of the first embodiment are designated by the same reference numerals. It is attached.

The cylindrical body 9 has a flange 9a at the lower end, and the flange 9a is fixed by a bolt 13 to the flat plate portion 5c.
It is fixed to. The stopper 8a is provided with a long groove 8b which is opened at the outer end instead of the bolt hole, and the spring receiver 14 is attached to the lower end surface of the stopper 8a. The coil spring 11 is installed between the spring receiver 14 and the flange 9 a of the cylindrical body 9. The bolt 10 passes through the long groove 8b of the stopper 8a and the hole of the spring receiver 14,
It is fitted in the screw hole of.

In the second embodiment, the bolt 13 can be removed and the bolt 10, the spring receiver 14, the coil spring 11 and the cylindrical body 9 can be removed through the long groove 8b in the working posture. FIG. 7 shows the state.

In the above-described embodiment, the bolt 10 is used as a means for holding the support bracket 8 at an arbitrary vertical position.
Although the coil spring 11 and the coil spring 11 are shown, a jack-up device may be used.

[0017]

According to the first aspect of the present invention, the position of the guide sheave can be easily changed manually without using an auxiliary crane or the like during transportation and operation of the crane. According to the second aspect, it is possible to remove the holding means of the support bracket, which is unnecessary in the working posture, and thereby the lifting capacity of the crane is not reduced.

[Brief description of drawings]

FIG. 1 is a side view in a work posture showing a first embodiment of the present invention partially in section.

FIG. 2 is a side view showing a state in which the work posture of FIG. 1 is changed to the transport posture;

3 is an enlarged front view taken along the line AA of FIG.

4 is a side view showing the guide member in FIG. 3,

5 is a side view corresponding to FIG. 1 showing a second embodiment of the present invention,

6 is an enlarged sectional front view of FIG. 5 corresponding to FIG. 3;

FIG. 7 is a side view showing a state in which the holding means of the support bracket is removed from the state of FIG.

FIG. 8 is a side view showing a tip portion of a conventional crane boom.

[Explanation of symbols]

 1 boom 2 guide sheave 4 hoisting wire rope 5 guide member 5a vertical plate portion 5b guide elongated hole 5c flat plate portion 5d screw hole 6 guide sheave shaft 8 support bracket 8a stopper 8b long groove 9 cylindrical body 9a flange 10 bolt 11 coil spring 12 bolt 13 bolt

Claims (2)

[Claims] 1. A guide sheave is provided on a rear surface of a tip of the boom.
In a crane boom where a point sheave is attached to the front end of the tip and the hoisting wire rope unwound from the crane body is hung from the guide sheave to the point sheave,
A guide member having vertical guide slots is attached to the rear end of the boom, and the guide sheave shaft supported by the support bracket is inserted into the guide slot so that it can move up and down. A guide sheave storage device comprising a holding means for holding the support bracket at an arbitrary vertical position and a fixing means for fixing the support bracket at a predetermined position of the guide member. 2. The guide sheave storage device according to claim 1, wherein the holding means is configured to be detachable from the guide member and the support member.