JP2776669B2 - Hook overwind prevention device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing a hook from being overwound in a crane or the like.

[0002]

2. Description of the Related Art Conventional hook overwind prevention devices include:
The one shown in FIG. 8 is known. In this hook overwinding prevention device, a hoisting rope 1 is suspended from a top sheave (not shown) at the tip of a boom (not shown), and a hook (not shown) is attached to a lower end of the hoisting rope 1. . Reference numeral 2 denotes a weight cone, and the hoisting rope 1 passes through a through hole of the weight 2. One end of a connecting rod 3 is connected to the weight 2, and the other end of the connecting rod 3 is connected to one end of a weight suspension rope 4 whose other end is connected to a detector 5 mounted on a boom. Have been. In such a configuration, when the hoisting rope 1 is hoisted by a predetermined amount or more and the weight 2 is lifted by the hook, the tension of the weight hanging rope 4 is reduced and the microswitch built in the detector 5 operates. As a result, an alarm signal is output and winding is stopped.

[0003] In such a conventional overwinding prevention device, a connecting rod 3 made of a rigid body is connected to the weight 2 side.
Connecting rod 3 even when weight 2 rotates around hoisting rope 1
Hits the hoisting rope 1, making it harder to rotate further,
By such an operation, the malfunction of the hook overwinding prevention device due to the winding of the weight suspension rope 4 is prevented.
Also, in the specification of Japanese Utility Model Application No. Sho 60-177197,
The weight is suspended at the center in the width direction, and the substantially parallel axes provided on the left and right sides of the weight are guided by two hook ropes for winding up hook blocks in the front-rear direction to prevent the rope from being entangled with the rope. It has been disclosed.

[0004]

As is well known, crawler cranes are used not only for crane operations but also for excavation operations such as clam-shull operations, and the frequency and speed of hoisting and turning vary depending on the operation. . For this reason, in the above-mentioned conventional device for preventing overwinding of the hook, even when the winding of the weight suspension rope 4 around the hoisting rope 1 can be prevented in a specific operation, the winding is completely prevented in a certain operation. However, there is a problem that the malfunction of the hook overwinding prevention device cannot be sufficiently prevented. Also, the hook overwinding prevention device described in the application specification of Japanese Utility Model Application Laid-Open No. Sho 60-177197 is intended for a device having two hook ropes in the front-rear direction (two hooks). When applied to a single hook (one hanging hook), the weight tends to rotate around the hook rope due to the eccentricity of the weight and the guide portion, and the weight is entangled with the hook rope. The problem cannot be improved.

An object of the present invention is to provide a hook overwinding prevention device capable of taking an optimum winding prevention method according to a work situation and sufficiently preventing a malfunction in any work situation.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1, 4 and 5 showing an embodiment, a hook overwinding prevention device according to the present invention is provided with a detector 1 attached to the tip of a boom.
5 is connected to the weight 21 by a pair of connecting rods 20A and 20B.
A lower end connecting portion 20b is formed at a lower end of the upper end connecting portion 20b so as to be connected to the weight 21, and an upper end connecting portion is integrally connected to the upper end by a connecting device 19 or separated from the connecting device 19 to be separated. 20a are formed respectively, and FIG.
As shown in FIG. 5, a first hanging form in which the upper ends of the connecting rods 20A and 20B are integrally connected by a connecting device 19 and connected to a heavy-cone suspension rope 16, and as shown in FIG.
A second suspension form in which the upper ends of the connecting rods 20A and 20B are separated and one is connected to the heavy cone hanging rope 16A and the other is connected to the boom tip via the other heavy cone hanging rope 16B. It is configured to be used selectively.

[0007]

The upper ends of a pair of connecting rods 20A and 20B respectively connected to both sides of the weight 21 are integrally connected by a connecting device 19, and the connecting device 19 is connected to the weight hanging rope 16 by a first method. A hanging system can be realized. In addition, if the connecting device 19 is removed and the upper ends of the connecting rods 20A and 20B are separately connected to the weight suspension ropes 16A and 16B, the second suspension method can be realized.

In the first suspension system, when the weight 21 is about to rotate, the connecting rods 20A and 20B are pulled up by the hoisting rope 1.
And the rotation of the weight 21 can be prevented. On the other hand, the second
In the hanging method, the weight cone 21 is pulled in opposite directions by a pair of weight hanging ropes 16A and 16B.
The rotation of the weight 21 can be prevented more reliably than in the first suspension method. Connecting rod 2 by attaching / detaching connecting instrument 19
Depending on whether the upper ends of 0A and 20B are combined or separated, an optimal system for the work can be easily and quickly selected from the two suspension systems depending on the work situation.

In the means and means for solving the above problems which explain the constitution of the present invention, the drawings of the embodiments are used to make the present invention easy to understand. However, the present invention is not limited to this.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. The same components as in the conventional example are denoted by the same reference numerals, and description thereof will be omitted. 1 to 7
Shows a hook overwinding prevention device according to the present invention.
The hook overwinding prevention device is characterized in that it can easily and easily select one of two use methods, that is, a one-weight suspension method and a two-weight suspension method according to the work situation. Therefore, the single weight suspension method will be described below with reference to FIGS. 1 to 4, and the double weight suspension method will be described with reference to FIGS. 5 to 7.

First, in FIGS. 1 to 4 showing a single weight suspension method, reference numeral 10 denotes a tip of a boom. This boom 1
The top sheave 11 is provided with a top sheave 11, and the hoisting rope 1 is wound around the top sheave 11. A hook block 12 for hanging a suspended load 13 is connected to a lower end of the hoisting rope 1. On the other hand, a detector support member 14 is provided at the tip of the boom 10, and a detector 15 is suspended from the detector support member 14. The detector 15 has a built-in micro switch, and this micro switch is turned on / off by the tension of the weight suspension rope 16 connected to the detector 15.

As shown in FIG. 4, a ring-shaped thimble 17 is provided at the lower end of the weight suspension rope 16, and is bound by a rope clip 18. A shackle main body 19a of a shackle (connecting device) 19 is hooked on the thimble 17, and a pair of connecting rods 20A and 20B are connected to the shackle main body 19a.
B, a shackle bolt 19b is provided in the mounting hole 20a at the tip end.
Are connected by inserting.

At the lower ends of the connecting rods 20A and 20B, a double cone 2 is provided.
1 is attached. The weight cone 21 is formed in a substantially cylindrical shape, and is provided with a through hole 21a at the center portion for allowing the hoisting rope 1 to pass therethrough. Mounting holes 21b are provided at both ends in the radial direction of the upper surface of the weight 21, and mounting pins 20b inserted into the mounting holes provided at the lower ends of the connecting rods 20A and 20B are provided in these mounting holes 21b. The mounting pin 20b is prevented from coming off by the fitting pin 21c and the washer 21d. Therefore, the connecting rod 20 is swingably connected to the weight 21. The weight 2
The first through hole 21a is communicated with the outside through a notch 21e, and the hoisting rope 1 is inserted into the heavy cone 21 from the notch 21e. The notch 21e has a block 21
f is fitted, and this block 21f is fixed with a fastener 21g.

In such a configuration, the hoisting rope 1
Is wound up by a certain amount or more, the hook block 12 pushes up the weight 21. For this reason, the tension of the weight hanging rope 16 is lost, the micro switch built in the detector 15 is operated, an alarm signal is output from the micro switch, and the winding is stopped. Is prevented.

In the single weight suspension system described above, when the weight 21 attempts to rotate, the connecting rods 20A, 20A
B hits the hoisting rope 1 and rotation of the weight 21 is prevented. At this time, since the lower ends of the two connecting rods 20A and 20B are respectively connected to both ends in the radial direction of the weight 21, the restoring force can be applied with a large moment to the rotation of the weight 21. The rotation of the weight 21 is effectively prevented as compared with the case of the book connecting rod. Furthermore, weight 2
Since 1 is formed in an axially symmetric cylindrical shape, inertial force is less likely to be applied even when the weight cone starts to rotate as compared with the case where the center of gravity of the weight is eccentric, and the rotation can be stopped easily. Therefore, it is possible to effectively prevent the weight suspension rope 16 from being wound around the hoisting rope 1 and prevent the hook overwinding prevention device from malfunctioning.

Next, the two-weight suspension method will be described with reference to FIGS. FIG. 1 shows a single-weight suspension method.
The same reference numerals are given to the same components as those in Nos. 1 to 4, and description thereof will be omitted. In this use state, as shown in FIGS. 5 and 7, the upper and lower portions of the connecting rods 20A and 20B are reversed from those in the case of a single suspension system, and the upper ends thereof are separated by separate weight suspension ropes 16A and 20A.
16B, and is suspended in a substantially V-shape so that the interval between them increases as going upward. here,
One weight suspension rope 16A is connected to a detector support 14A via a detector 15, and the other weight suspension rope 16A
B is connected directly to detector support 14B.

As described above, in the double weight suspension method, the pair of connecting rods 20A, 20B and the weight suspension ropes 16A, 16B are suspended from the hoisting rope 1 as they move upward. Therefore, a pulling force acts on the weight cone 21 in the opposite direction to each other, and a strong restoring force acts on the rotation of the weight 21, so that the weight 2 is smaller than the single hanging type.
1 can surely be prevented from rotating. Therefore, the winding of the weight suspension ropes 16A and 16B around the hoisting rope 1 is reduced by one.
This can be more reliably prevented than in the case of the main suspension method, and the malfunction of the detector 15 can be reliably prevented. This use state is suitable for heavy work and a lot of vertical vibrations, for example, for work such as a hammer club, an earth drill, and a bucket. In the second suspension system, when the hoisting rope 1 swings in the direction of arrow A in FIG. 7, the heavy-cone suspension rope 16A on the detector 15 side may loosen and lose tension, and the detector 15 may malfunction. For this reason, in the case of work such as crane work in which the turning speed is high and the hoisting rope 1 is likely to sway, the above-described single suspension system is preferable to the two suspension system. That is, this 2
This suspension system is suitable for work in which the roll of the hoisting rope does not become so large.

As described above, in the present embodiment, a pair of connecting rods 20A,
The lower ends of 20B are connected to each other to form connecting rods 20A, 20B.
Since the upper end of B is connected to the weight hanging rope via the shackle 19, the upper end of the connecting rod 20 can be easily attached and detached only by removing the bolt 19b of the shackle 19. Therefore, it is possible to easily and quickly select the single-weight suspension method and the double-weight suspension method. Therefore, in a normal crane operation, work is performed with a single weight suspension method, and when it is desired that the hoisting rope 1 is not so severely swayed and a malfunction is reliably prevented, use the double weight suspension method. be able to. In this manner, the most suitable method can be easily and quickly selected from the two use methods having the respective characteristics according to the work situation, and the malfunction of the hook overwinding prevention device is sufficiently prevented as a whole. be able to. Further, as in the present embodiment, if it is possible to easily switch between the single suspension system and the two suspension system simply by reversing the pair of connecting rods 20A, 20B, the number of parts is not increased. Two methods can be selected.

Although the shackle 19 is used as the connecting device, the connecting device is not limited to this, and other devices can be used as long as the connecting rod 20 and the weight hanging rope 16 can be easily attached and detached. Good.

[0020]

As described above, according to the present invention,
The lower ends of the pair of connecting rods are respectively connected to both sides of the weight, and the upper ends of the connecting rods are connected to the weight suspension rope via a detachable connecting device. A first suspending method of connecting the connecting device to the weight hanging rope and a second hanging method of separately connecting the upper ends of the pair of connecting rods to the weight suspending rope are easily and quickly selected. be able to. Therefore, the optimum use state can be adopted according to the work situation, and the malfunction of the hook overwinding prevention device can be sufficiently prevented as a whole.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a use state of hanging a single weight in an embodiment of a hook overwinding prevention device according to the present invention.

FIG. 2 is a side view showing a use state of a single weight suspended in the embodiment shown in FIG. 1;

FIG. 3 is a front view showing a use state of hanging one weight in the embodiment shown in FIG. 1;

FIG. 4 is a perspective view showing the connecting rod and the connecting device of the embodiment shown in FIG. 1;

FIG. 5 is a perspective view showing a use state of a double weight suspension in the embodiment of the hook overwinding prevention device according to the present invention.

FIG. 6 is a side view showing a use state of the double weight suspension in the embodiment shown in FIG. 5;

FIG. 7 is a front view showing a use state of the double weight suspension in the embodiment shown in FIG. 5;

FIG. 8 is a side view showing a conventional hook overwinding prevention device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hoisting rope 10 Boom 12 Hook block 15 Detector 16, 16A, 16B Weight hanging rope 19 Connection device 20A, 20B Connection rod 21 Weight

Claims (1)

(57) [Claims] 1. A detector is attached to the end of a boom, a weight is hung from the detector via a weight hanging rope and a connecting member, a hoisting rope is passed through the weight, and the weight is raised by winding the hoisting rope. In a hook overwinding prevention device that operates when a load acting on the detector is reduced by lifting the cone and outputs an alarm signal, the connecting member includes a pair of connecting rods, and lower ends of the pair of connecting rods. A lower end connecting portion is formed respectively so as to be connected to the weight, and an upper end connecting portion is formed at the upper end so as to be integrally connected by a connecting device or detached from the connecting device to be separated from each other, A first hanging mode in which the upper ends of the connecting rods are integrally connected by the connecting device and connected to the heavy cone suspension rope; And a second hanging form in which the other is connected to the end of the boom via another heavy-pyramid hanging rope. .