JPH06156984A - Crane boom - Google Patents

Abstract

PURPOSE:To convert the posture of a bracket into a working posture and a transport posture by simply changing the height of a guide sheave at an upper boom without need of an auxiliary crane. CONSTITUTION:A bracket 16 is vertically rockably supported to the tip of an upper boom 4 through a support shaft 15. A point sheave 8 is attached to the front end part of the bracket 16 through a sheave shaft 17, and a guide sheave 7 is attached to the rear end part of the bracket 16 through a sheave shaft 18. The bracket 16 is fixed to the upper boom 4 by means of a fixing pin 23 such that the bracket is brought into a working posture where the guide sheave 7 is positioned in a high level and a transport posture where the guide sheave 7 is positioned in a lower level.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lattice boom type crawler crane, a truck crane, etc. for removing and disassembling a connecting boom and disassembling and transporting it with an upper and lower boom.

[0002]

2. Description of the Related Art FIG. 5 shows a working posture of an example of a crawler crane. A revolving unit 2 is rotatably mounted on an endless track type traveling unit 1, and a lower boom 3 is provided in front of the revolving unit 2.
A boom composed of the upper boom 4 and the connecting booms 5 and 6 is attached so as to be able to be hoisted. A guide sheave 7 is attached to the rear surface of the tip of the upper boom 4, and a point sheave 8 is attached to the front surface of the tip. A hoisting rope 1 unwound from a winch 9 installed on a revolving structure 2.
0 is hung on a guide sheave 7 and a point sheave 8, and a bucket 11 and a lifting magnet are hung on it. In a work such as a bucket work or a lifting magnet work, which is subject to impact, the hoisting rope 10 may hit the upper boom (4) and the connecting booms (5, 6) on the upper surface (rear surface) to cause damage. Therefore, the guide sheave 7 should be installed as high as possible.

FIG. 6 shows a state in which the connecting booms 5 and 6 are removed, the lower boom 3 and the upper boom 4 are connected to each other, and the crane 13 is carried on the trailer 13 which is pulled by a trailer truck 12. Upper boom 4 and trailer truck 12
A gap G is provided between the driver's cab and the driver's cab so as not to hit the operator's cab even if the upper boom 4 vibrates. In this state, the height H1 of the upper end of the guide sheave 7 of the upper boom 4 is higher than the highest ground height H2 of the crane body, and the height limit during transportation is determined by this height H1. Generally, in the case of premises movement, facilities such as pipelines are set based on the main body trailer transportation height H2, and transportation with the upper boom 4 becomes impossible at a maximum ground height significantly higher than this. Therefore, the upper boom 4 must be removed and transported separately, disassembling and assembling takes time, and a large crane for lifting the upper boom 4 and a truck for transportation are also required, which is a large-scale transportation work. I will end up.

Therefore, various measures have been taken to reduce the height of the guide sheave 7 during transportation. In a utility model application publication No. 62-5187, which is one example thereof, as shown in FIG. 7, a bracket 31 to which a guide sheave 7 is attached is attached to a bracket receiver 3 provided on an upper boom 4.
A guide sheave storage device adapted to be held in two storage positions is described. In order to change the working state to the transporting state shown in the figure, the bracket 31 is hung by a crane or the like, the fixing pin 33 is removed and then lowered, and the fixing pin 33 is fixed again in the lower pin hole of the bracket receiver 32.

Another example, utility model application publication No. 1-10
No. 9090, as shown in FIGS. 8 and 9, a pair of left and right inward lugs 34 and outward lugs 3 are provided at the tip of the upper boom 4.
5 and the pair of left and right links 36A and 36B for supporting the guide sheave 7 on both lugs are respectively pins 37 and
A guide sheave storage device connected by eight is described. In order to change the illustrated working state to the transporting state, in the guide sheave storage device of FIG.
A is connected to the outward lug 39 mounted above the outward lug 35, and in the guide sheave storage device of FIG. 9, the pin 37 is removed, and both links 36A and 36B are swung to the lower storage position. 37 is inserted again to hold the guide sheave 7 in the lower storage position.

In another example shown in FIG. 10, a bracket 40 having a guide sheave 7 is attached to the upper boom 4 by a fulcrum pin 41 so that the bracket 40 can swing vertically.
Can be fixed to a work posture position indicated by a chain line and a transport posture position indicated by a solid line and a broken line via a fixing pin 42.

[0007]

In the above-mentioned prior art, the fixing pin must be removed and the bracket and the link must be assembled, and an auxiliary crane is required to suspend them. In addition, it is necessary to finely align the pins, and work is dangerous. Furthermore, the fixing pin must be fitted with a retaining means, which is complicated.

The present invention does not require an auxiliary crane,
It is an object of the present invention to provide a crane boom in which the guide sheave can be easily replaced in the position of the transportation posture.

[0009]

According to the crane boom of the present invention, a bracket is supported on the tip of the upper boom via a support shaft so as to be swingable in the front-rear direction, and a sheave shaft is provided at the front end of the bracket. A point sheave via the sheave shaft and a guide sheave on the rear end via a sheave shaft, and the bracket is fixed to the boom in a work position in which the guide sheave is in a high position and in a transport position in which the guide sheave is in a low position. It is characterized by having fixing means.

[0010]

In transporting, the guide sheave can be replaced with the lower position in the transporting posture by releasing the fixing of the bracket by the fixing means and swinging the bracket in the working posture around the support shaft.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be described.

A storage frame 14 having a trapezoidal planar shape is formed at the tip of the upper boom 4, and a bracket 16 swings in the front-back direction via a support shaft 15 in the storage frame 14. Being supported so that you can. A point sheave 8 is attached to the front end of the bracket 16 via a sheave shaft 17, and a guide sheave 7 is attached to the rear end of the bracket 16 via a sheave shaft 18. A rope guide 19 also serving as a handle is integrally provided at an end of the bracket 16 on the sheave shaft 18 side. Upper boom 4
In the side plate portion of, the upper pin hole 20 for fixing the bracket 16 in the working posture and the lower pin hole 21 for fixing the bracket 16 in the transport posture are the same with the support shaft 15 as the center. It is provided on an arc. Bracket 16
Is provided with a pin hole 22 that matches the pin holes 20 and 21.

The solid line in FIGS. 1 and 2 shows a state in which the fixing pin 23 is inserted into the upper pin hole 20 of the upper boom 4 and the pin hole 22 of the bracket 16 to fix the bracket 16 in the working posture. The sheave 7 is held in a high position. The chain line in FIG. 2, and FIGS. 3 and 4 show that the fixing pin 23 is pulled out from the working posture described above, the rope guide 19 is pushed down to swing the bracket 16, and the pin hole 23 of the bracket 16 is placed on the lower side of the upper boom 4. The guide sheave 7 is held at a low position in which the bracket 16 is fixed in the transporting position by inserting the fixing pin 23 into both the pin holes 23 and 21 so as to match the pin hole 21.

The weight of all the point sheaves 8 and all the guide sheaves 7, the sheave shaft 17, the sheave shaft 18, and the support shaft 15
If the moment on the point sheave 8 side and the moment on the guide sheave 7 side depending on the distance from
The bracket 16 can be easily swung, and the working posture and the transportation posture of the bracket 16 can be smoothly changed. In this embodiment, the distance between the support shaft 15 and the sheave shaft 18 is set larger than the distance between the support shaft 15 and the sheave shaft 17. It should be noted that the bracket 16 needs to be fixed by the left and right fixing pins 23 in the working posture from the viewpoint of strength, but there is no problem in fixing the bracket 16 by either one of the fixing pins 23 in the transporting posture.

[0015]

As described above, according to the present invention, the height of the guide sheave can be easily changed and the work posture and the transport posture can be smoothly changed without the need for an auxiliary crane. it can.

[Brief description of drawings]

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

FIG. 2 is an enlarged sectional side view showing the tip of the upper boom of FIG.

3 is a side view (cross-sectional view taken along the line AA of FIG. 4) in which the bracket is in a transporting posture from the state of FIG. 2;

FIG. 4 is a plan view of FIG.

FIG. 5 is a side view showing a work posture of an example of a conventional crawler crane,

FIG. 6 is a side view showing a transportation posture of an example of a conventional crawler crane,

FIG. 7 is a sectional side view showing a first example of a conventional guide sheave storage device;

FIG. 8 is a side view showing a second example of a conventional guide sheave storage device,

FIG. 9 is a side view showing a third example of a conventional guide sheave storage device,

FIG. 10 is a side view showing a fourth example of the conventional guide sheave storage device.

[Explanation of symbols]

 3 Lower boom 4 Upper boom 7 Guide sheave 8 Point sheave 14 Storage frame 15 Support shaft 16 Bracket 17 Sheave shaft 18 Sheave shaft 19 Rope guide 20 Pin hole 21 Pin hole 22 Pin hole 23 Fixing pin

Claims (2)

[Claims] 1. A bracket is supported on the tip of the upper boom via a support shaft so as to be swingable in the front-rear direction, and a point sheave is attached to the front end of the bracket via a sheave shaft, and a rear sheave is attached to the rear end. A crane characterized in that a guide sheave is attached via a sheave shaft, and a fixing means for fixing the bracket to the boom is provided in a working posture in which the guide sheave is in a high position and a transport posture in which the guide sheave is in a low position. boom. 2. The crane boom according to claim 1, wherein the moment on the point sheave side about the support shaft and the moment on the guide sheave side are set to be substantially equal to each other.