JP3419306B2 - Lift device safety device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lift device which can be lifted and lowered by a wire without having a mechanical guide post, and a lifter drops when the lift wire is cut. The present invention relates to a safety device designed to prevent

[0002]

2. Description of the Related Art In recent years, an all-weather temporary roof frame has been proposed as a temporary scaffold for construction of RC high-rise buildings. In this temporary roof frame, a plurality of temporary columns are erected around it according to the shape of the building to be constructed, and the temporary roof frame is supported above the temporary columns so that the height of the building frame is By raising the temporary roof frame while adding the temporary support pillars upward as the work progresses, the work can be performed without being affected by the weather. Further, an overhead crane is arranged on the lower surface of the temporary roof frame, and materials lifted by a lift device such as an elevator are transported to each part through the overhead crane.

As the above-mentioned lift device used for such a temporary roof frame, a lift device is used which normally lifts and lowers the lifter by a wire without having a mechanical guide post. As this lift device, for example, JP-A-5-106344 (Int.Cl.E04
G 21/16).

By the way, in such a lifting device, if the lifting wire is cut for some reason, the lifter may drop. Therefore, a safety device is required to prevent the lifter from falling due to cutting of the lifting wire. In the lift device disclosed in JP-A-5-106344, a stabilizer rope system installed to prevent the tilt of the lifter also serves as a safety device.

That is, in the above-mentioned conventional safety device, as shown in FIG. 14, in order to prevent the lifter 1 from rolling laterally, a pair of tensioned wires is arranged between the upper support portion 2 and the lower support portion 3. The intermediate portions of the stabilizer ropes 4 and 4a that are formed are made to cross each other at the position of the lifter 1 so that the sheaves 5 and 6 provided on the lifter 1 respectively circulate. Then, when the lifting wire is cut, the falling resistance of the lifter 1 is reduced by the rotational resistance of the sheaves 5 and 6.

[0006]

However, such a conventional safety device for a lift device slows down the lifter 1 only by the rotational resistance force of the sheaves 5 and 6 straddling the stabilizer ropes 4 and 4a as described above. ,
It was difficult to obtain a sufficient deceleration force for safely landing the lifter 1. In addition, stabilizer rope 4,
As the tension of 4a is increased, the rotational resistance of the sheaves 5 and 6 can be increased to increase the deceleration of the falling lifter 1. However, in this case, the stabilizer ropes 4 and 4a with increased tension are used. There is a problem that the above-mentioned temporary roof frame supporting the upper end of the vehicle is deformed and the driving resistance when the lifter 1 is moved up and down is increased.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a safety device for a lift device which can surely prevent the lifter from falling when cutting the lifting wire without affecting the lifting and lowering of the lifter.

[0008]

In order to achieve such an object, in a safety device for a lift device according to claim 1 of the present invention, a lifting wire is provided between an upper support part and a lower support part. Equipped with a lifter that can be lifted up and down via
In a lift device for lifting a suspended load by the lifter, stabilizer wires are provided in pairs between the upper support portion and the lower support portion, and the stabilizer wires are arranged to cross at the lifter position. However, a pair of rotating bodies are arranged on both sides with the intersecting portions of these stabilizer wires sandwiched between these stabilizer wires so as to be relatively movable.
It is constituted by providing rotation suppressing means for suppressing rotation in accordance with the cutting of the lifting wire and providing proximity moving means for bringing these rotating bodies closer to each other.

Further, in the safety device for a lift device according to claim 2 of the present invention, the cutting of the lifting wire is judged by the descending speed of the lifter, and the rotation suppressing means and the proximity moving means. Is configured to operate.

Further, in the safety device for a lift device according to a third aspect of the present invention, the rotation suppressing means is a disc brake.

Furthermore, in a safety device for a lift device according to a fourth aspect of the present invention, a biasing means for biasing the proximity moving means in a direction in which the rotating bodies approach each other, and the biasing means. Clamping means for restraining the rotating bodies from being separated from each other against the biasing force of the means and releasing the restraint according to the cutting of the lifting wire.

The operation of the safety device for a lift device according to the present invention having the above-described structure will be described below. In claim 1, the pair of stabilizer wires arranged between the upper support portion and the lower support portion is a lifter. Since a pair of rotating bodies are arranged so as to be relatively movable by being sandwiched between these stabilizer wires on both sides with the intersecting portion of these stabilizer wires sandwiched between them, each rotating body is in contact with both stabilizer wires and It rotates as the lifter moves up and down. At this time, both rotating bodies are provided with rotation suppressing means and proximity moving means, and when the lifting wire for lifting the lifter is cut for some reason, the rotation of the rotating body is suppressed and By moving the rotating bodies toward each other, the rotating bodies are braked and moved closer to each other, so that the pressure contact state with the stabilizer wire is increased. Therefore, the load of the lifter which is about to fall is supported by the rotating body and the intersecting portion of the stabilizer wire, so that the lifter operates at high speed due to the applied rotation suppressing force and the pressure contact force due to the proximity. It can be prevented or stopped from falling.

Further, according to a second aspect of the present invention, the cutting of the lifting wire is judged by the descending speed of the lifter, and the rotation restraining means and the proximity moving means are operated, whereby the natural falling speed of the lifter. It is possible to accurately judge the cutting of the lifting wire by the speed difference between the normal lowering speed and the lowering speed. Therefore, it is possible to prevent the rotation restraining means and the proximity moving means from erroneously operating during the normal lifting operation, and to surely prevent the lifter from dropping when the lifting wire is cut, thereby significantly improving safety. be able to.

Further, according to the third aspect of the present invention, by using the disc brake as the rotation suppressing means, a large braking force can be efficiently secured, and the braking force can be set steplessly. It is possible to control the braking including the stop, and to secure a stable braking force.

Still further, in claim 4, urging means for urging the proximity moving means to urge the pair of rotating bodies toward each other, and the rotating bodies against each other against the urging force of the urging means. When the lifting wire is restrained by the clamping means when the lifting wire is cut, the biasing means causes the lifting wire to be released from the lifting wire. The rotating body can be brought close to each other in an instant. Therefore, since the intersecting portion of the stabilizer wire can be quickly tightened by the rotating body without delaying the drop of the lifter, and the pressure contact force can be instantly increased, the drop of the lifter can be restricted from the beginning. Therefore, it is possible to more reliably prevent the lifter from falling, in combination with the rotation suppressing force of the rotation suppressing means.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. 1 to 13 show an embodiment of a lifting device according to the present invention, FIG. 1 is a plan view of an overhead crane equipped with the lifting device, FIG. 2 is a front view showing mainly a lifting wire system of the lifting device, 3 is a side view mainly showing the lifting wire system of the lifting device, FIG. 4 is a front view showing mainly the stabilizer wire system of the lifting device, FIG. 5 is a side view showing mainly the stabilizer wire system of the lifting device,
FIG. 6 is a top view of the lifter, FIG. 7 is a bottom view of a main part of the upper support portion, FIG. 8 is an enlarged front view of the lifter during normal operation, FIG. 9 is an enlarged plan view of the lifter, and FIG. 10 is a view of the lifter during braking. Enlarged front view, FIG. 11 is an enlarged front view of the rotation suppressing means, FIG.
1 is an enlarged front view showing a cross section of a main part of the proximity moving means, FIG.
3 is an enlarged front view showing an operating state of the proximity moving means.

The lift device of the present embodiment shows a case where it is used for hoisting materials to an overhead crane installed on a temporary roof frame of the all-weather construction method, and in this all-weather construction method, as shown in FIG. By covering the upper part of the building frame 10 to be constructed with a temporary roof frame 12 to prevent rainwater from entering the construction site,
The temporary roof frame 12 is supported by a plurality of temporary columns 14. The temporary support columns 14 are added upward as the construction of the building frame 10 progresses to lift the temporary roof frame 12.

The overhead crane 16 is installed on the lower surface of the temporary roof frame 12. The overhead crane 16 includes a transport rail 18 attached to the central portion of the temporary roof frame 12,
Built-in rails 20 and 20a are provided on both sides of the transport rail 18 and mounted in parallel with the transport rail 18. A dual transfer girder 22 is movably attached to the transfer rail 18, and built-in girders 24 and 24a are movably supported on the built-in rails 20 and 20a. The double transfer girder 22 is configured as a double type including a first girder 22a and a second girder 22b that are provided side by side in the extending direction of the transfer rail 18. First and second girder 22
A hoist 26 for suspending materials is movably attached to the a and 22b and the built-in girders 24 and 24a. The hoist 26 is transferable with the transport girder 22 and one built-in girder 24 or the other built-in girder 24a arranged in a straight line. A lift device 30 is installed on the side of the cargo take-in side end portion 18a of the transport rail 18, and a lifter 32 of the lift device 30 lifts materials from the ground portion to the overhead crane 16. The lifter 32 is formed in a substantially rectangular shape in a plan view, and on its lower surface, two vertically movable girders 34a, 34b are arranged in parallel with each other in a direction perpendicular to the transport rail 18. Mounted as. The vertically movable girders 34a, 34b are made of H-shaped steel having the same cross-sectional shape as the first and second girders 22a, 22b, and the hoist is provided between the vertically movable girders 34a, 34b and the first and second girders 22a, 22b. 26 transfers are possible.

As shown in FIGS. 2 to 5, the lift device 30 includes a lifting wire system A for suspending and lifting the lifter 32, and a stabilizer wire system for preventing the lifter 32 from rolling laterally. B and. The stabilizer wire system B includes the vertical movement girders 34a, 34b.
The lifting wire system A is provided in a pair at a right angle to the stabilizer wire system B (Y direction).

Each lifting wire system A includes a series of lifting wires 36 and a lifting winch 38, and the lifting winch 38 is installed on the ground G as a lower support. As shown in FIG. 6, the lifting wire 36 extended upward from the lifting winch 38 is passed through a guide roller group 40a provided at one end of the lifter 32 in the Y direction, and then, on the temporary roof frame 12 as an upper support portion. A group of guide rollers 40 provided around the other end of the lifter 32 in the Y direction, which circulates around the paired first sheaves 42a, 42b for lifting.
It is guided to the ground G through b, and is fixed via the tension measuring load meter 43 at this ground G portion.

At this time, as shown in FIG. 7, a pair of second lifting sheaves 42c and 42d are provided between the first lifting sheaves 42a and 42b of the temporary roof frame 12, and the pair of second lifting sheaves 42c and 42d are provided. The lifting wire 36 hanging from between the two sheaves 42c and 42d is wound around the pair of lifting sheaves 44a and 44b provided on the upper surface of the lift 32, and is suspended in the manner of a moving pulley. Therefore, in the lifting wire system A, when the lifting winch 38 is wound up, the lifter 32 rises with a movement amount which is half the winding amount, while when the lifting winch 38 is rewound, the lifter 32 is similarly wound. It descends with a movement amount that is half of the return amount. And the winch 38
Is capable of supporting a load twice as much as the supporting load.

Each stabilizer wire system B is provided with a series of stabilizer wires 46 and a stabilizer winch 48 for expanding and contracting the wire and adjusting the tension, and the stabilizer winch 48 is installed on the ground G as a lower support portion. As shown in FIG. 6, the stabilizer wire 46 fed out from the stabilizer winch 48 is passed through a guide roller group 50a provided at one end of the lifter 32 in the X direction, and then the temporary roof frame 12 serving as an upper support portion. The stabilizer sheave 52 attached to the pair
It goes around a and 52b, and is guided to the ground G through a guide roller group 50b provided at the other end of the lifter 32 in the X direction, and is fixed to the fixing portion 54 at this ground G portion.

At this time, the stabilizer wire 46 is
Is a group of guide rollers 50a and 50b provided on the lifter 32 and the sheave 52 for the stabilizer, as shown in FIG.
It can be hung on a cross between a and 52b. That is, sub-guide rollers 50c and 50d are provided on the upper surface of the lifter 32 near the guide roller groups 50a and 50b, and the stabilizer wire 46 that circulates around the guide roller group 50a at one end is inclined downward toward the other end. The stabilizer wire 46 is looped around from below the sub-guide roller 50c to the stabilizer sheave 52a.
Is bent in a crank shape on the upper side of the lifter 32 and arranged. Further, the stabilizer wire 46, which circulates around the guide roller 50b at the other end, is routed while being inclined downward toward the one end, and circulates from below the sub guide roller 50d around the stabilizer sheave 52b. The stabilizer wire 46 is bent in a crank shape and arranged.

Therefore, the stabilizer wire 46 is crossed in a cross shape on the upper side of the lifter 32, and the lifter 32 can be restrained at this intersecting portion. This makes it possible to prevent the lifter 32 from rolling laterally by applying a predetermined tension force to the stabilizer wire 46 with the winding force of the stabilizer winch 48. Of course, when the lifter 32 is moved up and down by driving the lifting wire system A, the guide roller group 50a,
The relative movement of the lifter 32 and the stabilizer wire 46 is allowed by the rotation of the 50b and the sub guide rollers 50c and 50d. Further, at the intersecting portions of the stabilizer wires 46, a predetermined interval S is set in the Y direction between the pair of stabilizer wires 46 as shown in FIG. 9, so that the respective stabilizer wires 46 are different from each other. It does not rub.

In this embodiment, as shown in FIG. 8, on both sides of the stabilizer wire 46 sandwiching the intersecting portion P of the stabilizer wire 46 arranged on the cross at the position of the lifter 32, between the stabilizer wires 46. A pair of rotating bodies 5 which can be sandwiched and relatively movable in a direction of approaching each other.
6, 56a are arranged. As shown in FIG. 11, a disc brake 58 as a rotation restraining means is provided on each of the rotating bodies 56, 56a, and a clamp device 60 as a proximity moving means is provided as shown in FIG. A safety device is constructed if 36 is disconnected. The disc brake 58 is the lifting wire 3 described above.
6 has a function of applying a rotation suppressing force, that is, a braking force to the rotating bodies 56, 56a according to the cutting of No. 6, while the clamp device 60 shows the rotating bodies 56, 56a according to the cutting of the lifting wire 36. As shown in 10, it has a function to move so as to approach each other.

The rotating bodies 56, 56a are attached to the respective support shafts 62, 62a, and the support shafts 62, 62a are
62a is rotatably attached to the movable supports 64 and 64a whose axial distance L is variable by the clamp device 60. The disc brake 58 is electromagnetically driven,
The rotation of the disks 66, 66a attached to the support shafts 62, 62a is stopped. Therefore, by operating the disc brake 58, the rotating bodies 56, 56a are braked.

On the other hand, the clamp device 60 is provided with a guide base 68 for movably supporting the rotating bodies 56, 56a in the directions approaching each other, and the guide base 68 is fixed to the upper surface of the lifter 32. A rack 70 extending along the moving direction of the movable support bases 64, 64a is formed inside the guide base 68, and the rack 70 is rotatable at the bases of the movable support bases 64, 64a. Two pinions 72 attached to each other mesh with each other, and these pinions 72 can move while rotating along the rack 70.

Between the pair of movable supporting bases 64, 64a, arms 74 forming a pair are provided on both outer sides of the guide base 68, and as a biasing means having a predetermined pulling force between these arms 74. Tensile springs 76 are attached, and the tension springs 76 allow the movable supports 64, 64a to be moved.
Are urged toward each other. Further, an electromagnetic clamp 78 is provided between the movable support bases 64 and 64a to hold them in a direction in which they are separated from each other.

That is, the respective movable supports 64, 64a
The links 80 are rotatably formed in a pair and extend from each other. The intermediate portions of the links 80 are supported by the support links 82, and the electromagnetic clamp 78 is attached between the tip ends of the links 80. Then, as shown in FIG. 12, in the clamped state of the electromagnetic clamp 78, the movable support base 6 is set with the support link 82 as a fulcrum and the base side of the link 80 is opened.
On the other hand, while the electromagnetic clamps 78 are released as shown in FIG. 13, the movable support bases 64, 64a are moved closer to each other by the distance L1 by the urging force of the tension springs 76, while separating the movable support bases 4, 64a.

The disc brake 58 and the electromagnetic clamp 78 are operated in response to the cutting of the lifting wire 36, and the cutting of the lifting wire 36 is performed by the lifter 3.
It is determined by the descent speed of 2. That is, the lifter 32 is provided with a sensor (not shown) for detecting the relative speed with respect to the ground or the building side, and this sensor detects that the descending speed (including the fall acceleration) of the lifter 32 exceeds the set value. The lifting wire 36 is cut. The disconnection of the lifting wire 36 can also be detected by the tension measuring load meter 43. When it is determined that the lifting wire 36 is cut by the tension measuring load meter 43 or the sensor, the disc brake 58 is operated to brake the rotating bodies 56 and 56a, and the electromagnetic clamp 78 is released. The rotating bodies 56, 56a are brought close to each other by the urging force of the tension spring 76.

In the lift device 30 according to the present embodiment having the above-described structure, the hoist 26 is placed in a state in which the hoist 26 is positioned on one of the vertically moving girders 34a and 34b forming the double girder 34 provided on the lifter 32. The lifter 32 is lowered, and the hoist 26 is slid with a material (not shown) at the ground portion. When the lifter 32 is lowered in this manner, the lifting wire 36 is unwound from the lifting winch 38, and the portion hanging from between the second lifting sheaves 42c and 42d extends long downward.

Then, by rotating the lifting winch 38 in the lifting direction, the lifting wire 36 is wound and the lifter 32 is lifted. Then, at the position where the lifting of the lifter 32 is completed, the double transfer girder 22 of the overhead crane 16 is laterally attached to the double girder 34 composed of the vertically movable girders 34a and 34b, and the vertically movable girders 34a and 3b.
The hoist 26 in the suspended state is transferred from one of the 4b to the one of the first and second girders 22a and 22b of the dual transport girder 22. At this time, the first and second girders 22a, 2
By positioning the empty hoist 26 on the other side of 2b, the hoist 26 in the suspended state is transferred to the dual transfer girder 22, and at the same time, the empty hoist 26 is transferred to the other of the vertically moving girders 34a, 34b. be able to. Therefore, the lifter 32 has two vertically movable girders 34a, 34
Since b is provided, the hoist 26 in the suspended state and the empty hoist 26 can be exchanged smoothly between the lift device 30 and the overhead crane 16.
The transport efficiency can be significantly improved.

Then, after the hoist 26 in the suspended state is taken in the double transfer girder 22, the double transfer girder 22 moves the transfer rail 18 and one of the built-in girders 24, 24a provided on the left and right. Be attached horizontally to the built-in girder 24,
The empty hoist 26 is fed from one side of 24a to the double transfer girder 2.
After receiving it, the hoist 26 in a suspended state is transferred to one of the built-in girders 24, 24a in exchange for this. After that, one of the built-in girders 24 and 24a is moved along one of the built-in rails 20 and 20a to which it is attached, and the hoist 26 in a suspended state is moved along one of the built-in girders 24 and 24a. By moving, the material can be transported to the target site on the construction floor of the building frame 10.

By the way, when the lifter 32 is moved up and down by the lifting wire system A composed of the lifting wire 36 and the lifting winch 38, the stabilizer wire 46 of the stabilizer wire system B is tensioned and the lifter 32 of the lifter 32 is tightened. Since the guide rollers 50a and 50b are arranged in a cross shape, the lifter 32 can be restrained by the tension force of the stabilizer wire 46 to prevent lateral swaying while allowing the lifter 32 to move up and down. .

Here, a pair of rotating bodies 56, 56a are arranged on both sides of the crossing portion P of the stabilizer wire 46 hung on the cross at the position of the lifter 32 so as to be relatively movable by being sandwiched between the stabilizer wires 46. Therefore, the rotating bodies 56 and 56a rotate as the lifter 32 moves up and down while contacting both stabilizer wires 46. At this time, a disc brake 58 and a clamp device 60 are provided on both of the rotating bodies 56, 56a, and a lifting wire 36 for lifting the lifter 32.
Is disconnected for some reason, the disc brake 58 is activated to apply a braking force to the rotating bodies 56 and 56a, and the electromagnetic clamp 7 of the clamp device 60 is connected.
8 is released and both rotary bodies 56, 56a are moved in the approaching direction.

Therefore, when the rotating bodies 56, 56a move closer to each other, the pressure contact force between the crossing portion P and the stabilizer wire 46 increases, and the frictional force between them increases.
56a is braked. Therefore, since the load of the lifter 32 which is about to fall is supported by the rotating bodies 56 and 56a and the intersecting portion P of the stabilizer wire 46, the lifter 32 is added by a braking force and a pressure contact force due to proximity. It is also possible to slowly lower 32 or stop it by increasing the braking force by the disc brake 58.

As described above, the safety logic of the lift device 30 is divided into the rotation restraining means by the disc brake 58 and the proximity moving means by the clamp device 60 to clarify the respective functions, so that the lifter 32 drops. Since the prevention can be surely guaranteed, it is possible to configure a system that the user can use with peace of mind.

In this embodiment, the lifting wire 3 is used.
Since the cutting of No. 2 is determined by the descending speed including the falling acceleration of the lifter 32 which is dropped due to the cutting of the lifting wire 36, the natural falling speed of the lifter 32 and the descending speed at the time of normal lifting operation are compared. The difference in speed enables the cutting of the lifting wire 36 to be determined without error.
Therefore, during normal lifting work, the disc brake 58 is
Also, the clamp device 60 is prevented from operating accidentally, and the lifter 32 is cut when the lifting wire 36 is cut.
Can be reliably prevented from falling, and safety can be significantly improved.

Further, since the disc brake 58 is used as the rotation suppressing means as described above, a large braking force can be efficiently secured, and this braking force can be set steplessly. Therefore, the falling speed of the lifter 32 is reduced. In addition, it is possible to arbitrarily control including the stop thereof and to secure a stable braking force.

Furthermore, as described above, the tension moving spring biases the pair of rotating bodies 56, 56a toward each other, and the rotating body 56 against the biasing force of the tensile spring 76. , 56a are restrained in a state of being separated from each other, and an electromagnetic clamp 78 for releasing the restraint in accordance with the cutting of the lifting wire 36 is provided, so that the electromagnetic clamp 78 is released when the lifting wire 36 is cut. By the tension spring 76, the rotating bodies 56, 56a can be brought close to each other in an instant. Therefore, lifter 3
Since the crossing portion P of the stabilizer wire 46 can be quickly tightened by the rotating bodies 56 and 56a without delaying the drop of 2 and the press contact force can be instantly increased, the drop of the lifter 32 is regulated from the beginning. You can Therefore, in combination with the braking force of the disc brake 58, the lifter 32 can be more reliably prevented from falling.

Further, the stabilizer wire 46 is tightened by bringing the rotating bodies 56, 56a close to each other by the clamp device 60, and the stabilizer wire 46 is wound by the winding of the stabilizer winch 48 at the same time when the rotating bodies 56, 56a are made close. By applying a large tension force, the effect of preventing the lifter 32 from falling can be further increased.

Further, the disc brake 58 and the clamp device 60 are of an electromagnetic type, and at the time of power failure, the disc brake 58 and the clamp device 60,
Further, since the electromagnetic brake of the stabilizer winch 48 itself cannot be operated, in this case, a standby power source such as a battery is used, and the lifter 32 is operated by the above operation.
Emergency stop.

By the way, in this embodiment, the rotating bodies 56, 5
Although the case where the disc brake 58 is used as the rotation restraining means of 6a and the clamp device 60 is used as the proximity moving means has been disclosed, the present invention is not limited to the disc brake 58 and the clamp device 60, and the rotating bodies 56, 5 are not limited thereto.
Any structure can be used as long as it can apply a rotation restraining force for braking 6a and a means that can tighten the intersecting portion P of the stabilizer wire 46 by bringing the rotating bodies 56, 56a close to each other.

[0044]

As described above, in the safety device for the lift device according to the first aspect of the present invention, the pair of stabilizer wires arranged between the upper support portion and the lower support portion is provided. , At the lifter position, a pair of rotating bodies are placed on both sides of the stabilizer wire so that they can move relative to each other, sandwiching the intersecting portions of these stabilizer wires, so that each rotating body contacts both stabilizer wires. Meanwhile, it rotates as the lifter moves up and down. At this time, since both the rotating bodies are provided with the rotation suppressing means and the proximity moving means, when the lifting wire for lifting the lifter is cut for some reason, the rotation suppressing force is applied to the rotating body. In addition, both rotating bodies can be moved toward each other, the rotating bodies can be braked, and the rotating bodies can be moved close to each other to increase the pressure contact state with the stabilizer wire. Therefore, since the load of the lifter that is about to fall can be supported by the intersection of the rotating body and the stabilizer wire, it is possible to prevent the lifter from dropping at high speed due to the applied rotation restraining force and the pressure contact force due to the proximity. It can be prevented or stopped, and the safety of emergency of cutting the lifting wire can be significantly improved.

Further, in the safety device for a lift device according to claim 2 of the present invention, the cutting of the lifting wire is
Since the rotation restraining means and the proximity moving means are actuated by judging the lifter descending speed, it is possible to correctly judge the cutting of the lifting wire based on the speed difference between the natural falling speed of the lifter and the normal descending speed. can do. Therefore, it is possible to prevent the rotation restraining means and the proximity moving means from erroneously operating during the normal lifting operation, and to surely prevent the lifter from dropping when the lifting wire is cut, thereby significantly improving safety. be able to.

Furthermore, in the safety device for a lift device according to claim 3 of the present invention, since the rotation restraining means is a disc brake, a large braking force can be efficiently secured and the braking force can be eliminated. In order to be able to set in stages,
It is possible to control the falling speed of the lifter, including stopping the lifter, and to secure a stable braking force.

Further, in the safety device for a lift device according to claim 4 of the present invention, a biasing means for biasing the proximity moving means in a direction in which the pair of rotating bodies are brought closer to each other, and Since the rotating body is pulled away from each other and restrained against the biasing force of the biasing means, the clamp means is configured to release the restraint in accordance with the cutting of the lifting wire.
When the restraint by the clamp means is released when the lifting wire is cut, the rotating body can be brought close to each other in an instant by the biasing means. Therefore, the crossing portion of the stabilizer wire can be quickly tightened by the rotating body without delaying the drop of the lifter, and the pressure contact force can be instantly increased, so that the drop of the lifter can be regulated from the beginning. Therefore, the excellent effect that the lifter can be more reliably prevented from falling, in combination with the braking force of the rotation restraining means.

[Brief description of drawings]

FIG. 1 is a plan view of an overhead crane provided with a lift device according to an embodiment of the present invention.

FIG. 2 is a front view mainly showing a lifting wire system of the lifting device of FIG.

FIG. 3 is a side view mainly showing a lifting wire system of the lifting device of FIG.

FIG. 4 is a front view mainly showing a stabilizer wire system of the lift device of FIG.

5 is a side view mainly showing a stabilizer wire system of the lift device of FIG.

FIG. 6 is a top view of a lifter of the lift device of FIG.

FIG. 7 is a bottom view of a main part of an upper support portion of the lift device shown in FIG.

8 is an enlarged front view of the lifter of FIG. 1 during normal operation.

9 is an enlarged plan view of a lifter of the lift device shown in FIG.

10 is an enlarged front view of the lifter of FIG. 1 when braking a lifter.

FIG. 11 is an enlarged front view of rotation suppressing means used in the lift device of FIG.

12 is an enlarged front view showing a cross section of a main part of a proximity moving unit used in the lift device of FIG.

13 is an enlarged front view showing an operating state of the proximity moving means used in the lift device of FIG.

FIG. 14 is a schematic configuration diagram showing a main part of a conventional lift device.

[Explanation of symbols]

10 building frame 12 Temporary roof frame 30 lift device 32 lifters 36 Lifting wire 38 Lifting winch 46 Stabilizer wire 48 Stabilizer winch 56,56a Rotating body 58 disc brakes 60 Clamp device 76 tension spring 78 Electromagnetic clamp A Lifting wire system B Stabilizer wire system G ground P intersection

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-106344 (JP, A) JP-A-9-278322 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B66F 7/02 B66F 17/00 B66B 5/12 B66B 9/187

Claims (4)

(57) [Claims] 1. A lift device, comprising: a lifter, which is hung up and down via a lifting wire, between an upper support part and a lower support part, and the lifter lifts a suspended load by the lifter. And a pair of stabilizer wires are provided between the lower support portion and the lower support portion, and these stabilizer wires are arranged by crossing at the lifter position.
A pair of rotating bodies are arranged on both sides of the stabilizer wire so as to be relatively movable by being sandwiched between the stabilizer wires on both sides of the intersecting portion, and the rotating bodies are prevented from rotating in accordance with the cutting of the lifting wire. A safety device for a lift device, which is provided with rotation suppressing means and proximity moving means for bringing these rotating bodies closer to each other. 2. The safety of the lift device according to claim 1, wherein the cutting of the lifting wire is judged by the descending speed of the lifter, and the rotation suppressing means and the proximity moving means are operated. apparatus. 3. The safety device for a lift device according to claim 1, wherein the rotation suppressing means is a disc brake. 4. The approaching moving means restrains the rotating bodies from the biasing means for biasing the rotating bodies toward each other and the rotating bodies against each other against the biasing force of the biasing means. , Clamping means for releasing the restraint in accordance with the cutting of the lifting wire.
3. A safety device for a lift device according to any one of items.