JPH07206380A - Jib tilt stop device for tower crane - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a jib tilt stop device capable of standing up a tower with the jib extended in front of the tower without being restricted by the length of the jib with respect to the tower length. And [Structure] A stopper 5 attached to the lower jib 1c and a rotatable stopper receiving structure. The stopper receiver 6 is formed of two side plates 6a and a receiving plate 6b for receiving the stopper 5, and one end side of the two side plates 6a is rotated via a pin 8 to a bracket 7 provided on the upper surface of the upper tower 2a. It is movably attached, and has the supporting surface 6c at the other end side which comes into contact with the upper surface of the upper tower 2a during tower crane work. Further, a tension spring 9 for holding the stopper receiver 6 in the set position and a rope 10 for rotating the stopper receiver 6 in the release position are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jib tilt stop device for a tower crane.

[0002]

2. Description of the Related Art As shown in FIGS. 7 to 10, a tower crane comprises a tower 2 which is mounted on a crane body 1 so as to be capable of hoisting, a jib 3 which is capable of being hoisted on an upper tower 2a of the tower 2, and a jib. 3, the tower 2 is composed of an upper tower 2a, an arbitrary number of joint towers 2b and a lower tower 2c, and the jib 3 is an upper jib 3a.
And an arbitrary number of joint jib 3b and lower jib 3c. The conventional jib tilt stop device 40 is composed of a stopper 5 attached to the lower jib 3c and a stopper receiver 60 attached to the upper tower 2a. As shown in FIG. It is fixedly attached to the tower 2a by welding or the like.

[0003]

Therefore, when an attempt is made to assemble the jib 3 extending in front of the tower 2 as shown in FIG. 3, the relative angle β between the tower 2 and the jib 3 becomes the work shown in FIG. Since it becomes larger than the jib upper limit angle α at the time,
There is a problem that the stopper 5 and the stopper receiver 60 interfere with each other. For this reason, conventionally, as shown in FIG. 9, the tower 2 must be erected while holding the jib 3 under the tower 2. That is, in order to hold the jib 3 under the tower 2, the jib length with respect to the tower length must be made smaller than the dimension D shown in FIG. 9, and there is a restriction on the jib length with respect to the tower length. It was For this reason, when building a building with a low height and a large width, such as a warehouse, a combination of a short tower 2 and a long jib 3 may be used as shown in FIG.
In the tower crane using, the situation shown in FIG. 8 is produced, and there is a waste of transporting and assembling the joint tower 2b in the shaded portion which is not necessary for the work.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a jib tilt stop device capable of standing up a tower with the jib extended in front of the tower without being restricted by the length of the jib with respect to the tower length. .

[0005]

SUMMARY OF THE INVENTION The present invention relates to a jib tilt stop device for a tower crane, which comprises a stopper attached to a lower jib and a stopper receiver attached to an upper tower, wherein the stopper receiver is provided on the upper tower side. In addition to being rotatably mounted, the stopper receiver can be held at a release position where it does not interfere with the stopper when the tower is erected horizontally, and at a set position for supporting the stopper when the tower is upright. To do.

[0006]

According to the present invention, the stopper receiver is rotatably attached to the upper tower side, and the stopper receiver is supported at the release position where it does not interfere with the stopper in the previous period when the tower is horizontally erected, and when the tower is upright, the stopper receiver is supported. Since it can be held at each set position, it is possible to select an appropriate combination of tower and jib according to the work.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a side view of a main part of a tower crane showing a setting position of a stopper receiver, and FIG.
A sectional enlarged view, FIG. 3 is an overall side view showing a standing state of the tower, and FIG. 4 is an enlarged side view of a portion of FIG.

The jib tilt stop device 4 of the present invention comprises a stopper 5 attached to the lower jib 3c and a stopper receiving structure shown in FIGS. The stopper receiver 6 includes two side plates 6a and a receiving plate 6b that receives the stopper 5.
And one end side of the two side plates 6a is rotatably attached to a bracket 7 provided on the upper surface of the upper tower 2a via a pin 8. The other end side of the two side plates 6a has a support surface 6c that comes into contact with the upper surface of the upper tower 2a during the tower crane operation shown in FIG. A pin 6d is provided at the center of the two side plates 6a for hooking the end of the tension spring 9 that holds the stopper receiver 6 at the set position by bringing the support surface 6c into contact with the upper surface of the upper tower 2a. , One end of the rope 10 is attached to the pin 6d. The other end of the rope 10 is wound around a guide sheave 11 or the like provided at a proper position of the upper tower 2a, and passes through the joint tower 2b and the lower tower 2c as shown in FIG. 3 so that the pulling operation can be performed on the ground. Is configured.

When assembling a tower crane in which the short tower 2 and the long jib 3 are combined, that is, when the jib 3 is extended to the front of the tower 2 as shown in FIG. 3, the tension spring 9 is used. Pull the rope 10 against the
The stopper receiver 6 is rotated to a release position where it does not interfere with the stopper 5, and in this state the rope 10 is secured to the lower tower 2c and the like. With this configuration, the tower can be horizontally erected without the jib tilt stop device 4 interfering. When the rope 10 is loosened after the tower is upright, the tension of the tension spring 9 causes the stopper receiver 6 to rotate so that its supporting surface 6c abuts the upper surface of the upper tower 2a, and the stopper receiver 6 is held at the set position. Needless to say, when the jib 3 is held under the tower 2 and the tower is raised, the rope 10 may be loosened from the beginning.

FIGS. 5 and 6 are views corresponding to FIGS. 1 and 4 showing another embodiment. As shown in FIG. 5, the stopper receiver 16 further extends one end side of the stopper receiver 6 downward, and at the end of the stopper receiver 16 when the tower 2 is horizontal.
A weight 17 for rotating 6 by moving the center of gravity is attached. Reference numeral 18 denotes a rotation stop bracket for positioning the stopper receiver 16 at the release position.

When the tower is horizontal, the stopper receiver 16 is held at the release position by the moment of gravity f × W acting on the weight 17, as shown in FIG. Also,
During the work after the tower is upright, the stopper receiver 16 is held at the set position by the moment e × W acting on the weight 17.

[0012]

As described above, according to the present invention,
The stopper receiver is rotatably attached to the upper tower side, and the stopper receiver can be held at a release position where it does not interfere with the stopper when the tower is horizontally erected and at a set position where the stopper is supported when the tower is upright. Since it is configured as described above, it is possible to provide a jib tilt stop device in which an appropriate combination of tower and jib can be selected according to the work, and thus it is possible to improve the workability of the tower crane.

[Brief description of drawings]

FIG. 1 is a side view of an essential part of a tower crane according to the present invention,

2 is an enlarged cross-sectional view taken along the line AA of FIG.

FIG. 3 is an overall side view showing a horizontal standing state of the tower of the present invention,

FIG. 4 is an enlarged side view of a portion of FIG. 3 showing a stopper receiving release position;

FIG. 5 is a side view of an essential part corresponding to FIG. 1, showing another embodiment of the present invention;

FIG. 6 is an enlarged side view corresponding to FIG. 4, showing another embodiment of the present invention;

FIG. 7 is an overall side view showing the working postures of the building and the tower crane,

FIG. 8 is an overall side view showing a work posture of a building and a tower crane,

FIG. 9 is an overall side view showing a horizontal standing state of a tower crane adopting a conventional jib tilt stop device;

FIG. 10 is a partial side view showing a conventional jib tilt stop device.

[Explanation of symbols]

 2a Upper tower 3c Lower jib 5 Stopper 6 Stopper receiver 6c Support surface 8 Pins 9 Tensile spring 10 Rope 16 Stopper receiver 17 Weight 18 Bracket

Claims (1)

[Claims] 1. A jib tilt stop device for a tower crane comprising a stopper mounted on a lower jib and a stopper receiver mounted on an upper tower, wherein the stopper receiver is rotatably mounted on the upper tower side, and A jib swing stop device for a tower crane, characterized in that the stopper receiver can be held at a release position where it does not interfere with the stopper when the tower is horizontally erected and at a set position that supports the stopper when the tower is upright. .