JP2001302180A - Link device of tower crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a link connecting a swing lever to a pendant rope from being damaged by preventing an excessive load from acting on the link when a tower crane is brought into contact with the ground in a rest attitude. SOLUTION: A first apex angle part 16 of a swing lever 16 is connected to a link 50 for connecting a pendant rope 15 through a spring 60, and the link 50 is formed so as to be inclined relative to the ground when the swing lever 16 is brought into contact with the ground. Thus, when the link 50 is brought into contact with the ground when the swing lever 16 is brought into contact with the ground, the link 50 is inclined into an attitude along the ground so as to prevent an excessive load from acting on the link 50.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tower crane suitably used for transporting materials to a high place, for example, at a construction site.

[0002]

2. Description of the Related Art Generally, a tower crane is used at a construction site such as a high-rise building for carrying materials from the ground to a high place.

A tower crane is disclosed in, for example,
It has a structure as described in US Pat.

Here, the structure of the tower crane will be described with reference to FIG. The tower crane is a tracked traveling vehicle 1
A revolving body 2 rotatably provided on the traveling body 1, a tower boom 3 having a lattice structure provided at the front end of the revolving body 2 so as to be able to move up and down, and an up and down movement at the tip end of the tower boom 3 A jib boom 4 having a lattice structure to be provided, and a hoisting winch which is placed at the center of the revolving structure 2 and has an end connected to the tip of the tower boom 3 for feeding out and moving the tower boom 3 up and down. 5. An auxiliary hoisting winch 6 whose end is connected to the tip of the jib boom 4 and which is raised and lowered to move the jib boom 4 relative to the tower boom 3, and a wire rope suspended from the top of the jib boom 4. Raising the hook 8 provided at the tip,
It comprises a main winding winch 7 for lowering and a counterweight 9 as a counterweight provided at the rear end of the revolving unit 2.

[0005] One end of a pendant rope 10 having a predetermined length is connected to the tip of the tower boom 3, and a bridle device 11 having a plurality of sheaves is connected to the other end of the pendant rope 10. The wire rope 12 fed from the hoisting winch 5 is erected at the rear part of the revolving superstructure 2 and guided by an A frame 13 having a sheave at the top, between the bridle device 11 and a hanger 14 attached to the A frame 13. The tower boom 3 moves up and down by changing the distance between them.

Further, one end of a pendant rope 15 having a predetermined length is connected to the end of the jib boom 4, and the other end of the pendant rope 15 has a beam structure provided rotatably at the end of the tower boom 3. Triangular swing lever 16
Is connected to the first apex angle portion 16a. The wire rope 17 fed from the auxiliary winch 6 is connected via a bridle device 18 and a hanger 19 to one end of a pendant rope 20 having one end connected to the second apex portion 16b of the swing lever 16. You. The swing lever 16 has a third apex 16c rotatably attached to the tip of the tower boom 3 so that the jib boom 4 moves up and down. Bridle device 18, hanger 1
9 has a structure that performs the same operation as the bridle device 11 and the hanger 14 described above, and by changing the distance between them by a wire rope 17 looped between them,
The swing lever 16 rotates via the pendant rope 20. The swing lever 16 and the pendant rope 15 are connected via a link 50 pivotally supported by a connecting pin 30 in order to improve assembling and disassembly. (FIG. 6
See (a). In the tower crane configured as described above, when the crane operation is performed, the hoisting winch 5, the auxiliary winding winch 6, the main winding winch 7 and the like are driven in the posture as shown in FIG. , The jib boom 4 and the hook 8 are operated to move the suspended load.

When the crane operation is completed, the jib boom 4 is held on the tower boom 3 as shown in FIG.

[0008]

In the resting posture shown in FIG. 5, since the jib boom 4 is fixed along the tower boom 3, the swing lever 16 rotates forward, The first apex 16a of the swing lever 16 comes into contact with the ground. As shown in FIG. 6A, which is an enlarged view of a portion a in FIG. 5, the first apex angle portion 16a of the swing lever 16 and the pendant rope 15 are connected via the link 50. Is placed in such a posture that its longitudinal direction is perpendicular to the ground due to the action of gravity, and if it touches the ground in this state, an excessive load acts on the link 50 or the connecting pin 30 to cause breakage. Therefore, each time the worker pulls the pendant rope 15 or the link 50 in the direction A in FIG.
The posture shown in FIG. The pendant rope 15 has a longer length along with the length of the jib boom 4 and a larger diameter due to its strength. Therefore, the pendant rope 15 is heavy, and this work requires too much labor. And the connection state between the jib boom 4 and the swing lever 16 may not be maintained in a smooth state.

[0009] The present invention solves the above-mentioned problems, and prevents the link itself from being damaged.
An object of the present invention is to provide a link device of a tower crane that can reduce a burden on an operator.

[0010]

In order to achieve the above-mentioned object, a link device for a tower crane according to the present invention comprises a main body, a tower boom provided on the main body so as to be able to move up and down, and a tip end of the tower boom. The present invention is applied to a tower crane having a jib boom and a swing lever that are rotatably provided on the vehicle, and a pendant rope for connecting the swing lever and the jib boom and raising and lowering the jib boom as the swing lever rotates. Claim 1
The invention is characterized in that the swing lever and the pendant rope are connected via a link, and the link is provided with a posture restraining means that takes a posture along the ground when the swing lever is in contact with the ground. is there.

Thus, in a state where the swing lever is in contact with the ground, the link connecting the jib boom and the swing lever is in a posture along the ground, the link itself is in contact with the ground, and the weight of the tower boom and the jib boom by the link. Can be avoided, and damage to the link can be prevented.

According to a second aspect of the present invention, the posture restricting means comprises a spring provided between the link and the swing lever.

According to a third aspect of the present invention, there is provided a main body, a tower boom provided on the main body so as to be able to move up and down, a jib boom and a swing lever rotatably provided at a tip end of the tower boom, and the swing lever and the jib. And applied to a tower crane having a pendant rope for raising and lowering the jib boom with the rotation of the swing lever, wherein the swing lever and the pendant rope are connected via a link, The link is
When the swing lever is in contact with the ground, the swing lever is disposed at a position where the swing lever does not contact the ground.

Thus, in the same manner as described above, when the swing lever is in contact with the ground, the link connecting the swing lever and the pendant rope does not contact with the ground, so that the load of the tower boom and the jib boom is received. Is eliminated, and breakage of the link can be prevented.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a link device for a tower crane according to the present invention will be described below with reference to FIGS.
In the present embodiment, the same components as those in the prior art shown in FIGS. 4 to 6 are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 1 is an enlarged view of a part a in FIG. 5 and shows one embodiment of a link device of a tower crane according to the present invention. FIG. 1A shows a first example of a swing lever 16 according to the embodiment. Is a state diagram showing a state immediately before the grounding of the apex corner portion 16a, and FIG.

As described above, the first apex 16a of the swing lever 16 is one end of the beam member constituting the swing lever 16, and one end of the link 50 is rotatably pivoted by the connecting pin 30 thereat. Supported, the other end is a connecting pin 3
1 supports the pendant rope 15. In FIG. 1, the first apex 16a of the swing lever 16 and the link 50 are connected by a spring 60, and the link 50 is constantly biased clockwise. As a result, the link 50 is constantly urged in the direction in which the pendant rope 15 extends, so that even if the jib boom 4 is set to the resting position along the tower boom 3 and the swing lever 16 tries to touch the ground, the link 50 does not move. Does not take a posture in which its longitudinal direction is perpendicular to the ground, and takes a posture inclined in a direction in which the pendant rope 15 extends, so that the link 50 tilts with the contact of the ground, and the first apex portion 16a of the swing lever 16 becomes Fig. 1 (b)
A posture along the ground as shown in FIG. Therefore link 50
The link 50 and the connecting pin 30 can be prevented from being damaged without an excessive load acting on itself. In addition, since the link 50 itself tilts with the touchdown, it is not necessary for the operator to pull the pendant rope 15 or tilt the link 50 each time, so that the burden can be reduced.

The spring 60 is configured to withstand the load due to the load of the link 50 and the pendant rope 15 due to its own weight.

Next, a second embodiment of the link device for a tower crane according to the present invention will be described with reference to FIG. 2 also shows an enlarged view of the part a in FIG. 5, as in FIG.

In this embodiment, a stopper 70 is provided near the center of rotation of the link 50 at the first apex 16a of the swing lever 16. When the swing lever 16 is brought into contact with the ground, the stopper 70 is provided so that the longitudinal direction of the link 50 is not orthogonal to the ground.
0 is prevented from rotating in that direction. In FIG. 2, a stopper 70 is provided at a position for restraining the rotation of the link 50 so that the link 50 does not touch the ground by rotation even if the swing lever 16 touches the ground. As a result, the link 50 and the connecting pin 30 can be prevented from being damaged when the swing lever 16 is grounded, as described above.

The position of the stopper 70 satisfies the above-mentioned condition, and the stopper 70 contacts the stopper 70 even if the link 50 rotates due to a change in the angle of the pendant rope 15 to which a large tension is applied during the crane operation. It is set to a position that does not.

Next, a third embodiment of the link device for a tower crane according to the present invention will be described with reference to FIG. Note that FIG. 3 also shows an enlarged view of a part a in FIG. 5 similarly to FIG.

In the present embodiment, even if the first vertex 16a of the swing lever 16 contacts the ground,
The link 50 is supported at a position where it does not touch the ground. According to this, when the swing lever 16 touches the ground, the longitudinal direction of the link 50 becomes perpendicular to the ground due to the action of gravity, but the link 50 does not touch the ground. Therefore, the damage of the link 50 can be prevented as in the case described above. Furthermore, in the present embodiment, other components such as a spring and a stopper are not required, so that the structure is simplified, and it is not necessary to consider the strength, mounting position, and the like of these components, which is advantageous in design. .

Of the first to third embodiments, the first and second embodiments can be easily retrofitted and can be applied to existing products.

[0025]

As described above, according to the link device of the tower crane of the present invention, when the jib boom is hung in the tower boom and the swing lever is to touch the ground when the tower crane is in the resting position, An excessive load does not act on the link, and damage to the link can be prevented.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged view of a main part of a link device for a tower crane according to a first embodiment of the present invention, wherein FIG. It is a figure which shows the state at the time of grounding.

FIG. 2 is an enlarged view of a main part of a second embodiment of a link device for a tower crane according to the present invention.

FIG. 3 is an enlarged view of a main part of a third embodiment of a link device for a tower crane according to the present invention.

FIG. 4 is an explanatory view of the overall structure of a tower crane to which the link device of the tower crane of the present invention is applied.

FIG. 5 is a state explanatory view illustrating a state in which a tower crane according to the related art is in a stopped state.

6A is an enlarged view of a part a in FIG. 5, wherein FIG. 6A is a view showing a state immediately before the swing lever is touched, and FIG.
It is a figure which shows the state in the grounding of a swing lever.

[Explanation of symbols]

 3 Tower Boom 4 Jib Boom 15 Pendant Rope 16 Swing Lever 16a First Apex 50 Link 60 Spring 70 Stopper

Claims (3)

[Claims] 1. A main body, a tower boom provided to be able to move up and down on the main body, a jib boom and a swing lever rotatably provided at a tip end of the tower boom,
A tower crane comprising a pendant rope for connecting the swing lever and the jib boom and for raising and lowering the jib boom with the rotation of the swing lever, wherein the swing lever and the pendant rope are connected via a link. A link device for a tower crane, wherein the link is provided with a posture restraining means for taking a posture along the ground when the swing lever is in contact with the ground. 2. The link device for a tower crane according to claim 1, wherein said attitude restricting means comprises a spring provided between a link and a swing lever. 3. A main body, a tower boom provided to be able to move up and down on the main body, a jib boom and a swing lever rotatably provided at a tip end of the tower boom,
A tower crane, comprising a pendant rope for connecting the swing lever and a jib and for raising and lowering the jib boom with the rotation of the swing lever, wherein the swing lever and the pendant rope are connected via a link. A link device for a tower crane, wherein the link is connected to a position where the swing lever does not touch the ground when the swing lever touches the ground.