JPH0340873Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a weight structure used in a crane hook overwind prevention device.

[Conventional technology]

FIG. 4 shows a perspective view of a conventional hook overwind prevention device, in which a weight 1 for the hook overwind prevention device is attached to a micro-micrometer attached to the upper part of a crane boom (not shown) via a chain 2 and a rope 3. It is suspended from Switch 4. 5 is a top sheave rotatably attached to the upper end of the crane boom. A hoisting rope 6 let out from a winch of a crane main body (not shown) is passed around the top sheave 5, inserted into the weight 1, and connected to the hook block 7. 8 is a hanging load suspended by the hook block 7.

When the hook block 7 pushes up the weight 1 by overwinding the hoisting rope 6, the tension in the chain 2 and rope 3 disappears, so the micro switch 4 is switched. As a result, the overwind warning device is activated and the winch is automatically stopped.

[Problem that the invention attempts to solve]

Since the weight 1 described above has an integral structure, when the load 8 is lifted from the ground in single-line work, a sudden load is applied to the hoisting rope 6 via the hook block 7. do.
Conversely, when lowering the suspended load 8 to the ground, the load acting on the hoisting rope 6 is rapidly reduced. The hoisting rope 6 is untwisted during the above-mentioned one-line hanging operation to generate rotational force. In other words, it rotates in a circle as shown by the arrow in FIG. Therefore, as shown in FIG. 6, from the micro switch 4 to the rope 3
And the weight 1 suspended by the chain 2 is
Due to the rotational friction with the hoisting rope 6, it rotates due to the resistance and eventually gets entangled with the hoisting rope 6. 7th
The figure shows a state in which the weight 1 is entangled with the hoisting rope 6 due to such rotation of the weight 1. If the hoisting and hoisting operations are continued in this state, the rope 3 will be cut and the function of the hook overwind prevention device as a safety device will become completely useless. Furthermore, if the rope 3 breaks, the weight 1 will naturally fall and hit the hook block 7, causing it to break apart, or the rope 3 will rotate below and hit the sling operator, which is extremely dangerous.

The present invention was made to solve the above-mentioned problems, and its purpose is to create a weight that can prevent the hanging rope of the weight for preventing overwinding of the hook from becoming entangled with the hoisting rope. It's about providing structure.

[Means for solving problems]

In order to achieve this objective, the present invention divides the weight for the hook overwind prevention device through which the hoisting rope is inserted into two parts, an upper weight and a lower weight, and a plurality of wire ropes etc. It is characterized by being connected by a material.

[Effect]

The lower weight directly receives the rotational action of the weight that occurs when breaking the ground in the above-mentioned one-line hanging work. This rotational movement of the lower weight is buffered by a cushioning material such as a wire rope, and is prevented from propagating to the upper weight.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in more detail with reference to FIG. The weight for preventing overwinding of the hook according to the present invention has an inner diameter D through which the hoisting rope 6 can be inserted.
an upper weight 11 having an upper weight 11, a lower weight 12 through which the hoisting rope 6 can be inserted and having an inner diameter d smaller than the inner diameter D, and three wires connecting the upper weight 11 and the lower weight 12. It is composed of a rope 13. The upper weight 11 is connected to the top sheave 5
A rope 3a for operating the micro switch is sandwiched between the
It is attached by hanging two ropes with a weight hanging rope 3b fixed to the boom. Since the wire rope 13 only needs to function as a buffer material,
It may also be composed of chains, springs, etc. Moreover, it goes without saying that any number of pieces may be used as long as there are a plurality of pieces.
As mentioned above, the lower weight 12 has an inner diameter d.
It is preferable to make the inner diameter D of the upper weight smaller than the inner diameter D of the upper weight 11, and to provide a bracket 12a for locking the upper weight 11 when the hook is overwound. Further, the hole through which the hoisting rope 6 is inserted may be a square hole.

As shown in Figure 2, the hoisting rope 6 at the time of ground cutting
The rotation hits only the lower weight 12, causing it to rotate. Fig. 3a shows that when turned to the left, Fig. 3b
The figure shows the case when it is turned to the right. At this time, the upper weight 11 is buffered by the wire rope 13,
The influence (propagation) of the rotational force on the upper weight 11 is extremely reduced. In addition, the upper weight 11 is suspended from two ropes, with one side fixed to the micro switch 4 by a rope 3a and the symmetrical side fixed to a boom on the opposite side of the micro switch 4, with the top sheave 5 at the center, so that it can be hoisted. It can be arranged so as not to come into contact with the rope 6. Therefore, the hoisting rope 6
When the hoisting rope 6 is hoisted up while only the lower weight 12 is affected by the rotational force of continues. Thereafter, the wire rope 13 slackens, and eventually the lower weight 12 hits the upper weight 11 and pushes the upper weight 11 upward. Therefore, the rope 3a,
3b operates the micro switch 4 without getting entangled with the hoisting rope 6, the safety device (hook overwinding prevention device) operates normally.

In addition, as shown in FIG. 3c, the wire rope 13 acts as a buffer against the jumping phenomenon of the weight that occurs due to interference between the hoisting rope 6 and the weight during sudden hoisting operations. Malfunctions can be prevented without affecting the weight 11.

(Effects of the invention) As described above, according to the weight structure according to the invention, the hook overwinding prevention device can work safely without malfunctioning. Therefore, accidents to third parties due to falling of the weight can be prevented. In addition, there is no need to stop work due to the weight getting tangled and to repair the work to restore normal operation. moreover,
If the weights become entangled frequently, many customers will have to remove the weights for preventing hook overwinding, which is dangerous, but this can be prevented.

[Brief explanation of the drawing]

Fig. 1 shows an embodiment of the present invention; Fig. 2 is a perspective view of a hook overwinding prevention device; Fig. 2 is a schematic perspective view showing the movement of a weight when the hoisting rope is rotated; Figs. Figure 3b is a schematic perspective view when the lower weight is turned by the hoisting rope, Figure 3c is a schematic perspective view when the lower weight is jumping, and Figure 4 is a perspective view of a conventional hook overwind prevention device. , Fig. 5 is a perspective view showing the rotational movement of the hoisting rope, Fig. 6 is a perspective view showing the movement of the conventional weight when the hoisting rope is rotated, and Fig. 7 is the state in which the conventional weight is entangled. FIG.

Claims (1)

[Claims for Utility Model Registration] (1) The weight for the hook overwinding prevention device through which the hoisting rope is inserted is divided into two parts, an upper weight and a lower weight, and a plurality of wire ropes, etc. are used as buffers between them. A weight structure for a hook overwind prevention device, which is characterized by being connected by a material. (2) A claim for utility model registration characterized in that the inner diameter of the lower weight is smaller than the inner diameter of the upper weight, so that interference with the hoisting rope on the weight is received only by the lower weight. A weight structure for a hook overwind prevention device as described in scope item (1).