JPH09278368A - A-frame supporting device and a-frame fitting/removing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate A-frame fitting/removing work by preventing the oscillation of a rear leg at the time of fitting/removing an A-frame. SOLUTION: A link 20 is rotatably fitted to a fitting part 22 of a front leg 11. At the normal time, the other end of the link 20 is fitted to a fixing part 25 of the front leg 11. At the time of fitting/removing work of an A-frame 10, the other end of the link 20 is fitted to a pin 24 of a rear leg, and the front leg 11 and the rear leg are integrally fixed in the state of maintaining an angle θ. Pins 13, 14, 16 are then removed, and a hook 18 is hooked to a wire rope 17 to lift the A-frame 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for supporting an A frame of a construction machine and a method of attaching and detaching the A frame to and from the construction machine.

[0002]

2. Description of the Related Art An example of a crawler crane is shown in FIG.
A boom 2 is movably connected to the front end of the crane body 1, and a hoisting rope 4 fed from a hoisting winch 3 is wound around the tip of the boom 2. A hook 5 is connected to the tip of the hoisting rope 4, and a hanging load (not shown) is hung on the hook 5. One end of a pendant rope 6 is fixed to the tip of the boom 2, and a bridle 7 is connected to the other end.

A boom hoisting rope 9 extended from a boom hoisting winch 8 reaches a sheave provided on a bridle 7 via a sheave provided on the top of an A frame 10, and further, a bridle 7 and an A frame hanger 30. It is wound multiple times between and the tip is A frame hanger 3
Fixed to 0. Therefore, when the boom hoisting rope 9 is retracted or extended by the winch 8 from the state of FIG.
The space between the A frame hanger 30 and the bridle 7 changes, and the boom 2 is undulated.

In such a crane, for example, as shown in Japanese Utility Model Laid-Open No. 60-12591, an A frame 1
No. 0 is attached to the crane body 1 so as to be capable of undulating.
FIG. 6 shows the structure of the A frame 10 that is attached to the crane body 1 so as to be able to rise and fall. As shown in FIG. 6, the above-described A frame 10 has a pair of left and right front legs 11 and a pair of left and right rear legs 12 (only one of which is shown), and one end of each front leg 11 has a pin 13 on the crane body 1. Thus, one end of the rear leg 12 is rotatably connected to the other end of the front leg 11 via the axle 31. One end of a hoisting cylinder 15 is connected to the front leg 11 by a pin 16, and the hoisting cylinder 15 expands and contracts to hoist the front leg 11 and thus the A frame 10.
Each rear leg 12 has a leg member 12B with respect to the leg member 12A.
The leg member 12C is of a telescopic type so that the leg member 12C can be inserted into and removed from the leg member 12B.
The leg member 12C is rotatably connected to the other end of the front leg 11 via the axle 31 while being rotatably connected to the front leg 11C. The leg member 12A is provided with a pin hole 12a at the upper end thereof, and the leg member 12B is provided with pin holes 12c and 12b at the upper and lower ends thereof, respectively.
A pin hole 12d is provided at the lower end of 2C. By inserting the pins into these pin holes 12a, 12b, 12c, 12d, the rear leg 12 can be fixed in the extended state (working posture) shown in FIG.

Further, the pin holes 12a, 12b, 12c, 1
Remove the pin from 2d and attach the leg member 12C to the leg member 12B.
The leg member 12B by inserting the leg member 12B into the leg member 12A and fixing them with pins.
A, 12B and 12C can be integrated to be fixed to the crane body 1 in the contracted posture shown in FIG.

[0006]

On the other hand, when the crane is transported, it may be necessary to remove the A frame 10 due to weight restrictions or height restrictions. In such a case, A
The frame 10 is in the retracted position shown in FIG.
And pin 1 for attaching the rear leg 12 to the crane body 1
Remove 3 and 14 and wire rope 1 as shown in Figure 8.
7 is attached, and the wire rope 17 is attached by the hook 18.
The A frame is detached from the crane main body 1 by hooking and lifting the A frame 10 upward.

However, when the A frame 10 is removed from the crane body 1 in the contracted posture shown in FIG. 7, the rear legs 12 swing back and forth as shown in FIG. It is an obstacle to removal work and difficult to perform. Also, the removed A frame 1
When 0 is attached to the crane, the rear leg 12 is attached to the crane body 1, the front leg 11 is aligned, and the pin is inserted into the pin hole to be fixed to the crane body 1. Since this alignment is an extremely detailed work for matching the pin hole of the front leg 11 and the pin hole of the crane body 1, the mounting work is difficult and time-consuming.

An object of the present invention is to provide an A frame support device and an A frame attachment / detachment method that enable easy attachment / detachment of the A frame to / from the crane body.

[0009]

FIG. 1 shows an embodiment of the present invention.
Describing in association with FIG. 3, the invention of claim 1 is the front leg 11 having one end rotatably supported on the construction machine body 1.
And the other end of the front leg 11 and the rear part of the main body of the construction machine, which is rotatably coupled, and is applied to a support device for an A frame 10 of a construction machine, which includes a front leg 11 and a rear leg 12. By fixing the front leg 11 and the rear leg 12 by connecting them to each other and providing the fixing member 20 fixedly housed in the front leg 11 or the rear leg 12 on at least one of the front leg 11 and the rear leg 12, To achieve.

According to a second aspect of the present invention, the front leg 11 has one end rotatably and detachably supported on the construction machine body 1.
And rotatably coupled to the other end of the front leg 11,
The method is applied to a method of attaching and detaching an A frame 10 of a construction machine having a rear leg 12 rotatably and detachably coupled to a rear part of the construction machine body to and from the construction machine body 1, and fixing the front leg 11 and the rear leg 12 After that, the front leg 11 and the rear leg 12 are attached to and detached from the construction machine body 1 to achieve the above object.

According to the first aspect of the present invention, the rear leg 12 is fixed to the front leg 11 by the fixing member 20. Further, both ends of the fixing member 20 are fixed to the front leg 11 or the rear leg 12 and stored when not in use. According to the second aspect of the present invention, after the front leg 11 and the rear leg 12 are fixed, the front leg 11 and the rear leg 12 are attached to the construction machine body 1 and removed from the construction machine body 1.

In the section of the means for solving the above-mentioned problems, which explains the configuration of the present invention, the drawings of the embodiments of the present invention are used to make the present invention easy to understand. However, the present invention is not limited to this.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of an A frame supporting device according to the present invention, showing a state in which the A frame is contracted and fixed to a crane main body, and FIG. 2 shows a state in which the A frame is removed from the crane main body and lifted. 3 and 4 are cross-sectional views taken along the line I-I of FIG. 1 showing the structure of the mounting member. 1 to 3, the same components as those described in the above-mentioned conventional technique are designated by the same reference numerals, and detailed description thereof will be omitted. As shown in FIGS. 1 to 3, a mounting portion 22 is provided on the side facing the rear leg 12 of the front leg 11, and one end portion of the link 20 is mounted on the mounting portion 22. As shown in FIG. 3, pin holes 20a and 20b are formed at both ends of the link 20, and by inserting the pin 23 into the pin hole 20a, the link 2
0 is rotatably supported by the mounting portion 22. Further, the other end of the link 20 is fixed to the leg member 12A by inserting the pin hole 20b into the pin 24 protruding outward from the side surface of the leg member 12A. As a result, the front leg 11 and the rear leg 12 are fixed while maintaining the angle θ. When the A frame 10 is used, the link 20 is fixed to the fixing portion 25 of the front leg 11 by the pin hole 20b at the other end.
Is fixed to the link 20 by the pin 21.
Is fixed to the front leg 11 as shown by the chain double-dashed line in FIG.

Next, the operation of the present invention will be described.
When removing the A frame 10 from the crane body 1, first, remove the pins from the pin holes 12a, 12b, 12c, 12d of the rear leg 12 in the same manner as in the conventional technique described above.
The leg member 12C is inserted into the leg member 12B, and the leg member 1
The leg members 12A, 12B, and 12C are integrated by inserting 2B into the leg member 12A and fixing them with pins. Next, the pin 21 is removed, and the link 20 is rotated in the direction of arrow A using the pin 23 as a fulcrum to move the leg member 12
The pin hole 20b is inserted into the pin 24 attached to A, and the other end of the link 20 is fixed to the leg member 12A. As a result, the front leg 11 and the rear leg 12 are fixed while maintaining the angle θ.

Then, the wire rope 17 is attached to a predetermined position of the front leg 11, the wire rope 17 is hooked on the hook 18, and the wire rope 17 is slightly lifted as shown in FIG. After that, the pins 13 and 14 connecting the crane body 1 to the front legs 11 and the rear legs 12 and the pin 16 connecting the hoisting cylinder 15 to the front legs 11 are removed. Then, when the hook 18 is further lifted, the A frame 10 is lifted upward as shown in FIG. In this state, since the front leg 11 and the rear leg 12 are integrally fixed by the link 20 while maintaining the angle θ, the rear leg 12 does not swing forward and backward and become unstable,
It does not interfere with the removal work of the A frame 10. Therefore, the removal work of the A frame 10 can be easily performed.

The A frame 1 thus removed
0 is attached to the crane body 1, the front leg 11 and the rear leg 12 are fixed by the link 20, and the rear leg 12
Is attached to the crane body 1 by the pin 14. After the rear leg 12 is attached to the crane body 1, the front leg 11 is attached to the crane body 1 with the pin 13. At this time, if the rear leg 12 is not fixed to the front leg 11, it is difficult to align the pin hole of the front leg 11 with the pin hole of the crane body 1, but the rear leg 12 is fixed to the front leg 11 by the link 20. Therefore, the alignment becomes easy. Therefore, the attachment work of the A frame 10 can be easily performed as in the removal work.

Thereafter, the front leg 11 of the A frame 10 is attached to the hoisting cylinder 15 by the pin 16. Then, the other end of the link 20 is removed from the pin 24 and attached to the fixing portion 25 of the front leg 11 with the pin 21, whereby the link 20 is fixed to the front leg 11 as shown by the chain double-dashed line in FIG.
Next, the leg members 12A, 12B, 12C are extended, and the rear leg 12 is fixed in the extended state (working posture) shown in FIG. 6 by inserting the pins into the pin holes 12a, 12b, 12c, 12d, whereby A The mounting work of the frame 10 is completed.

In the above embodiment, the link 20 is formed by forming the pin hole 20b in the link 20 and inserting the pin 24 of the leg member 12A into the pin hole 20b.
Is fixed to the leg member 12A, but the invention is not limited to this. For example, as shown in FIG. 4, a notch 20c is formed at the other end of the link 20, and the notch 20c is formed.
The link 20 may be fixed to the leg member 12A by engaging the pin 24 with the pin 24.

Further, in the above-mentioned embodiment, the front leg 11 and the rear leg 12 are fixed by the link 20, but, for example, one end of the rope is attached to the attaching portion 22 of the front leg 11 and the A frame 10 of the A frame 10 is fixed. At the time of attachment / detachment, the other end of the rope may be connected to the leg member 12A so that the front leg 11 and the rear leg 12 are fixed. Further, in the above embodiment, the link 20 is connected to the front leg 1
1 is attached to the rear leg 1
You may make it attach to 2. In the correspondence between the above-described embodiment and the claims, the link 20 constitutes a fixing member.

[0020]

As described above in detail, according to the invention of claim 1, the front leg and the rear leg are fixed by the fixing member. Therefore, when the A frame is attached to and detached from the main body of the construction machine, the rear leg is attached. No longer sways back and forth and becomes unstable,
The A frame can be stably lifted. Therefore, it is possible to easily attach and detach the A frame. Further, according to the invention of claim 2, after the front leg and the rear leg are fixed, the A frame is attached to and detached from the main body of the construction machine. Therefore, similarly to the invention of claim 1, the A frame is stably lifted. Therefore, the work for attaching and detaching the A frame can be easily performed.

[Brief description of drawings]

FIG. 1 is a side view showing the configuration of an A frame provided with an A frame supporting device of the present invention.

FIG. 2 is a diagram showing a state in which an A frame is lifted.

FIG. 3 is a sectional view taken along line II of FIG. 1;

FIG. 4 is a diagram showing a configuration of another embodiment of a fixing member.

FIG. 5 is a side view showing the configuration of a crawler crane.

FIG. 6 is a side view showing the configuration of a conventional A frame (working posture).

FIG. 7 is a side view showing the configuration of a conventional A frame (in a storage position).

FIG. 8 is a diagram showing a state in which a conventional A frame is lifted.

[Explanation of symbols]

 1 Crane main body 10 A frame 11 Front leg 12 Rear leg 12A, 12B, 12C Leg member 20 Link

Claims (2)

[Claims] 1. A front leg, one end of which is rotatably supported on a construction machine body, and a retractable rear leg, which is rotatably coupled to the other end of the front leg and a rear portion of the construction machine body. In a supporting device for an A frame of a construction machine, a fixing member that connects the front leg and the rear leg to fix the front leg and the rear leg, and that is fixedly housed in the front leg or the rear leg is stored. An A-frame supporting device provided on at least one of the front leg and the rear leg. 2. A front leg whose one end is rotatably and detachably supported on the construction machine main body, and is rotatably connected to the other end of the front leg and is rotatably attached to the rear part of the construction machine main body. A method for attaching and detaching an A frame of a construction machine having a rear leg detachably coupled to the construction machine main body, comprising: fixing the front leg and the rear leg, and then attaching the front leg and the rear leg to the construction machine. A characterized by being attached to and detached from the body
How to attach and detach the frame.