JP2851787B2 - Crane hook rotation prevention mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanism for preventing rotation of a hook attached to a crane for carrying heavy objects or the like. More specifically, the present invention relates to a mechanism capable of freely rotating in a no-load state, but having a suspended load. This relates to a mechanism in which the direction of the hook is restricted and cannot be rotated.

[0002]

2. Description of the Related Art A crane hook used in a conventional ordinary overhead traveling crane and the like is designed to be able to rotate freely even after hanging a load in order to move a suspended load to an arbitrary place. Has become. An example is shown in FIG. Bearings 12 are provided at both ends of a horizontally arranged shaft 10, respectively.
The sheaves 14 are attached via a wire, and a wire rope 16 is hung on both sheaves 14. The shaft 10 has a housing 18
Is fixed, and the hook 20 is suspended by a thrust bearing 22 in the housing 18. Both sheaves 14
Are covered with a cover 24 for safety.

[0003] As described above, the hook 20 is connected to the housing 18.
Because it is suspended by the thrust bearing 22 inside
The rotation of the hook is not restricted and is completely free even when there is no load when a load is not suspended or when a load is suspended. Such a rotation mechanism is for the crane operation assistant to directly rotate the suspended load so that the load can be placed in an arbitrary direction.

[0004]

However, when a heavy object is to be moved at a high place or in a poor working environment, it must be suspended at a work place where the worker cannot directly touch the suspended load. In the movement of the load, the rotation of the suspended load during the operation cannot be restricted, so that the rotation may cause the suspended load to come into contact with surrounding devices or structures and be damaged. At this time, there is a risk that a disaster such as a drop of a suspended load may occur. However, in the structure where the hook is simply fixed,
It becomes difficult to place the suspended load in an arbitrary direction, and the workability of moving and setting the load is deteriorated.

An object of the present invention is to allow a worker or a remote control device to freely rotate a hook when there is no load, but when a load of a suspended load is applied to the hook,
The rotation of the hook is regulated by the load, so if the location and direction of the suspended load are determined in advance, the suspended load can be transported even in places where workers cannot directly Another object of the present invention is to provide a crane hook rotation preventing mechanism which can be safely installed.

[0006]

The present invention comprises a shaft,
A crane hook having rotatable sheaves located at both ends of the shaft, a hook suspended from the shaft, a housing attached to the shaft, a lower block having a through-hole and fixed to the housing, and a lower block. An upper block positioned above the lower block, the base of the hook is fixed to the upper block in a state of penetrating the longitudinal hole of the lower block, and a protrusion is formed on one of opposing surfaces of the lower block and the upper block. And a crane hook rotation preventing mechanism having a plurality of recesses formed on the other side to be fitted to the projections. Here, a free space having a height equal to or higher than the protrusion height of the projection is provided above the upper block, and the upper block can be moved upward. It is preferable to provide a stopper at the base of the hook to regulate the range of its movement.

For example, the lower block is formed in a cylindrical shape and fixed to the lower center of the housing. The upper block also has a cylindrical shape having a vertical through hole in the center, and has a structure having a horizontal through hole in its diameter direction. The hook also has a transverse hole formed near its upper end. Then, with the base of the hook penetrating the central through hole in the lower block and the upper block, a fixing pin is inserted into the transverse hole of the upper block and the hook,
This secures the hook. A small diameter longitudinal hole is formed in the lower block, and a positioning pin having a hemispherical upper end is formed in the small diameter longitudinal hole so that the upper end protrudes from the upper surface of the lower block to form a projection. Form a recess in which the upper end of the positioning pin fits.
In this case, it is preferable that a plurality of positioning pins are disposed symmetrically with respect to the central axis at equal angles, and a plurality of depressions are also formed symmetrically with respect to the central axis at equal angles.

[0008]

When no load is applied, if the hook is slightly lifted, the upper block is lifted up relative to the lower block fixed to the housing, and the protrusion and the recess are disengaged. Can rotate. Next, when a load of a suspended load is applied, a large downward force is applied to the upper block, so that the projection is fitted into the depression by pressing against the lower block, and the hook is fixed in the same direction. This prevents free rotation of the hook. If there are many depressions, the number of mating combinations will increase,
The direction that can be specified also increases.

[0009]

FIG. 1 is an overall structural view showing an embodiment of a crane hook rotation preventing mechanism according to the present invention, and FIG.
FIG. Crane hook is shaft 30
And a sheave 34 rotatably supported by bearings 32 at both ends of the shaft 30, and a hook 40 suspended from the shaft 30. Further, the crane hook includes a housing 38 attached to the shaft 30,
A lower block 50 fixed to the housing 38 and an upper block 52 located above the lower block 50 are provided. The shaft 30 fixes the block plate 39 fixed with screws to the housing 38 so as not to rotate itself.

The lower block 50 has a cylindrical shape provided with a longitudinal hole 54 at the center, and is located at a position symmetrical with respect to the central axis.
A plurality of small-diameter longitudinal holes 56 are formed, and a positioning pin 58 having a hemispherical upper end is formed in each of the small-diameter longitudinal holes 56 so that the upper end protrudes from the upper surface of the lower block 50 to form a projection. It is. The lower block 50 is fixed to the lower center of the housing 38. Upper block 52
Is formed in a cylindrical shape having a longitudinal through hole 60 at the center, and has a transverse through hole 62 in the diametrical direction. On the lower surface, eight hemispherical recesses 64 into which the upper ends of the positioning pins 58 fit are fitted.
Is formed symmetrically with respect to the central axis. The hook 40 also has a through hole 41 formed near its upper end.

Then, the base of the hook 40 is inserted so as to penetrate through the central vertical holes 54 and 60 of the lower block 50 and the upper block 52, and is fixed to the horizontal hole 62 of the upper block 52 and the horizontal hole 41 of the hook 40. Insert pin 66, thereby securing hook 40. Note that a free space 68 having a height equal to or higher than the height of the protrusion is provided above the upper block 52 so that the upper block 52 can be moved upward. The base of the hook 40 is provided with a stopper 70 for regulating the range of movement.

The sheave 34 is smoothly rotated by the bearing 32, and the entire crane hook is freely raised and lowered by operation of the wire rope 36. When no load is applied, when the hook 40 is slightly lifted relatively, the upper block 52 rises with respect to the lower block 50 fixed to the housing 38, and the fitting between the projection (the tip of the positioning pin 58) and the recess 64 is released. . Therefore, in that state, the hook 40 can be freely rotated. On the other hand, when a load of a suspended load is applied, a large downward force is applied to the upper block 52, and the upper block 52 is pressed against the lower block 50, so that both projections are fitted into the recesses 64, and the hooks 40 are fixed in the same direction and rotated. Is regulated. In the above embodiment, since the eight depressions 64 are symmetrically disposed about the central axis, the direction of the suspended load can be designated at every 45 ° angle.

Although the preferred embodiment of the present invention has been described in detail, the present invention is not limited to such a configuration. Although a structure in which a fixing pin is inserted into the transverse through hole for fixing the hook and the upper block is adopted, any fixing structure may be used. In the above embodiment, the projections are provided on the lower block and the depressions are provided on the upper block. The number of projections may be one functionally, but it is preferable to provide a plurality of projections symmetrically with respect to the central axis from the viewpoints of prevention of shaft bias, hook balance, and ease of setting the rotation angle. Although the number of depressions is eight in the above embodiment, the number may be increased or decreased as appropriate according to the use or the use state. As the number of depressions increases, the orientation can be set finer. However, if the number is too large, the diameters of the upper block and the lower block must be increased, which complicates production. The protrusion may have a structure in which a ball is embedded so that a part thereof protrudes. In addition, it goes without saying that the shape and the like of each constituent member can be appropriately changed according to the use and the like.

[0014]

As described above, according to the present invention, a projection is formed on one of the opposing surfaces of the lower block fixed to the housing and the upper block to which the hook is attached, and a plurality of depressions are formed on the other surface. When no load is applied, the hook can be freely rotated by a worker or a remote control device. However, when a load of a suspended load is applied to the hook, the hook cannot be rotated due to the load. Since the hook direction can be regulated in this manner, the suspended load can be easily installed in a predetermined direction even in a place where it is difficult for an operator to approach. In addition, since the suspended load is prevented from rotating during movement, it is possible to prevent the suspended load and equipment from being damaged by contacting surrounding equipment and structures, and the danger of falling is eliminated. Extremely effective. Furthermore, even in the transfer work by remote control, the worker does not need to directly control the direction of the suspended load, and can work efficiently even in a poor work environment.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a crane hook rotation prevention mechanism according to the present invention.

FIG. 2 is an AA arrow view thereof.

FIG. 3 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 Reference Signs List 30 shaft 32 bearing 34 sheave 38 housing 40 hook 50 lower block 52 upper block 58 positioning pin 64 recess 66 fixing pin

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-213579 (JP, A) Japanese Utility Model Showa 64-47787 (JP, U) Japanese Utility Model Showa 61-122283 (JP, U) (58) Survey Field (Int.Cl. ⁶ , DB name) B66C 1/00-1/68

Claims (5)

(57) [Claims] 1. A crane hook having a shaft, rotatable sheaves positioned at both ends of the shaft, and hooks suspended from the shaft, the crane hook having a housing attached to the shaft, and having a longitudinal hole fixed to the housing. A lower block, and an upper block located above the lower block, wherein a base of the hook is fixed to the upper block in a state of penetrating a through hole in the lower block, and the lower block and the upper block. Characterized in that a projection is formed on one of the opposing surfaces and a plurality of depressions are fitted on the other of the projections. 2. A free space having a height equal to or higher than the protrusion height of the projection is provided above the upper block so that the upper block can move upward, and a movement range thereof is restricted by a base of the hook. The rotation preventing mechanism according to claim 1, further comprising a stopper. 3. The lower block has a cylindrical shape and is fixed to the lower center of the housing. The upper block also has a cylindrical shape having a longitudinal through hole in the center and has a transverse through hole in its diameter direction. A hook is fixed by inserting a fixing pin into the through hole of the upper block and the hook in a state where a through hole is formed near the upper end and the base of the hook penetrates the central through hole of the lower block and the upper block. The rotation preventing mechanism according to claim 1 or 2, wherein 4. The lower block has a small-diameter through-hole, and a positioning pin having a hemispherical upper end is provided in the small-diameter through-hole such that the upper end protrudes from the upper surface of the lower block to form a projection; 4. The lower surface of the upper block is formed with a recess into which the upper end of the positioning pin fits.
An anti-rotation mechanism as described. 5. The anti-rotation mechanism according to claim 4, wherein a plurality of positioning pins are disposed symmetrically about the central axis at an equal angle, and a plurality of recesses are formed symmetrically about the central axis at an equal angle.