JPH10225579A - Device for elevating item to be hung for stage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for elevating an item to be hung for a stage, which is excellent in manipultability and safety. SOLUTION: In a device for elevating an item 1 to be hung for a stage, a rope 2 for hanging the item 1 is wound on a sheave and is then connected to a counterweight 7 so that the item 1 is elevated in an opposite direction in which the counterweight 7 is moved. In this arrangement, a spring 12 is connected to the counterweight 7 so that loading displacement of the rope 2 caused by the elevation of the item 1 is absorbed by the resiliency of the spring 12 between the item 1 side and the counterweight 7 side. Irrespective of a position of the item 1, a pulling rope 9 can be operated by a slight constant force without changing the direction of a load upon the rope 9 during elevation of the item 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a stage
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manually-operated lifting device for raising and lowering a suspended object such as a curtain or an upholstery by operating a pulling line.

[0002]

2. Description of the Related Art Conventionally, a manually-operated lifting device for a stage as shown in FIG. 6 has been used. In this figure, one end of a plurality of hanging ropes 2 is attached to a hanging object 1 such as a curtain or an upholstery, and each of the hanging ropes 2 is a branch pulley provided on a pen D which is located above a stage S. 3 and the former pulley 4.

An elevating frame 5 is provided on a guide rail R extending vertically in the sleeve of the stage S so as to be able to move up and down. The other end of each suspension line 2 is connected to the elevating frame 5. A weight 6 is loaded on the mounting surface of the lifting frame 5, and the lifting frame 5 and the weight 6 constitute a counterweight 7 for the suspended object 1.

[0004] The upper and lower ends of the lifting frame 5 are connected to both ends of a pulley 9 provided between a pair of pulleys 8, 8 provided on the stage S and the sash D, respectively. 9
Lock device 10 is provided.

In this elevating device, the suspended object 1 can be raised and lowered in a direction opposite to the counterweight 7 by pulling the towing line 9.

[0006]

By the way, in the above hoisting and lowering device, if the weight of the hoisting line, the frictional resistance between each pulley and the hoisting line and the pulling line, the running resistance of the hoisting frame, and the like are ignored, the pulling rope starts to be pulled. Only by applying a force, the suspended object is lifted and lowered without applying a force thereafter.

However, in practice, the weight of the suspension line is so large that it cannot be ignored, and the load of the suspension line moving between the suspension side and the counterweight side with the lifting and lowering of the suspension is 20 kg.
In some cases, the rope must be operated against this load.

Further, since the direction of the load acting on the towline is reversed by the movement of the load of the suspension line, there is a danger in operating the towline, and the operator requires physical strength and skill.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a stage lifting device which is excellent in operability and safety.

[0010]

In order to solve the above problems, according to the present invention, a suspension rope for suspending a suspended object is wound around a pulley and connected to a counterweight. In a stage lifting device for raising and lowering in opposite directions, a spring is connected to either the counterweight or the lifting object, and the elastic force of the spring causes the lifting side and the counterweight side of the lifting and lowering of the lifting object. It was decided to absorb the load movement of the suspension rope between them.

Further, instead of the spring, a chain whose lower end is grounded may be connected to the counterweight, and the weight movement of the chain acting on the counterweight may absorb the load movement of the suspension rope.

In this elevating device, the rope can be operated with a constant small force regardless of the position of the suspended object, and the direction of load on the rope is not changed during lifting and lowering of the suspended object.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Parts corresponding to those of the conventional lifting device shown in FIG. 6 are denoted by the same reference numerals, and description thereof is omitted.

FIG. 1 shows a first embodiment of a lifting device according to the present invention. As shown in the drawing, a reel type spring 12 is installed in a pit formed in the sleeve of the stage S. The distal end of the wire 13 pulled out of the spring 12 is connected to the lifting frame 5 of the counterweight 7. The spring constant of the spring 12 is determined in accordance with a value obtained by multiplying the weight per unit length of the suspension rope 2 by the number thereof.
And the total load on the counterweight 7 is always balanced.

A specific example of the operation of the lifting device will be described with reference to FIG. Here, it is assumed that the weight of the suspended object 1 is 100 kg, the maximum value of the load movement of the suspension rope 2 is 20 kg, and the weight of the counterweight 7 is 80 kg.

As shown in FIG. 2 (a), when the suspended object 1 is lifted to the uppermost position, no winding force is generated in the spring 12, and the total of the suspended object 1 and the counterweight 7 side is not increased. The load is balanced at 100 kg each.

As shown in FIG. 2B, when the suspended object 1 is at the intermediate position, the winding force of the spring 12 is 20 kg, and the total load on the suspended object 1 side and the counterweight 7 side is 110 kg each. Be balanced.

As shown in FIG. 2 (c), when the suspended object 1 descends to the lowermost position, the winding force of the spring 12 becomes 40 kg, and the total load on the suspended object 1 side and the counterweight 7 side is:
Each weighs 120kg and balances.

As described above, the winding force of the spring 12 changes with the lifting and lowering of the suspended object 1, and absorbs the load movement of the suspension rope 2, so that a constant slight force is applied regardless of the position of the suspended object 1. The rope 9 can be operated, and the direction of load on the rope 9 does not change during the lifting and lowering of the suspended object 1.

FIG. 3 shows a second modification of the above embodiment.
1 shows an embodiment. In this elevating device, the spring 12 is provided on the pen D, and the tip of the wire 13 is connected to the suspended object 1.

Specifically, as shown in FIG. 3 (a), when the suspended object 1 is lifted up to the uppermost position, no winding force is generated in the spring 12, and the suspended object 1 side and the counterweight 7 are not wound. The total loads on the sides are balanced at 100 kg each.

As shown in FIG. 3B, when the suspended object 1 is lowered to the lowermost position, the winding force of the spring 12 is reduced to 40.
kg, and the total loads on the suspended object 1 side and the counterweight 7 side are each 80 kg, and are balanced.

FIG. 4 shows a third embodiment of the lifting device according to the present invention. In this elevating device, the counterweight 7
One end of the chain 14 is connected to the lifting frame 5.
The lower end of the chain 14 hangs down and is received by a chain box 15 having an open upper surface.

FIG. 5 shows a specific example of the operation of the lifting device. As shown in FIG. 5A, when the hanging object 1 is lifted up to the uppermost part, the entire weight of the chain 14 does not act on the counterweight 7 because the entire chain 14 is accommodated in the chain box 15. The total loads on the suspended object 1 side and the counterweight 7 side are each balanced at 100 kg.

As shown in FIG. 5 (b), when the suspended object 1 is lowered to the intermediate position, one end of the chain 14 is lifted with the rise of the counterweight 7, and the weight of the chain 14 acting on the counterweight 7 is reduced. 20 kg, and the total loads on the suspended object 1 side and the counterweight 7 side are each 110 kg, and are balanced.

As shown in FIG. 5C, when the suspended object 1 reaches the lowermost position, the chain 1 acting on the counterweight 7 is actuated.
4 has a weight of 40 kg, and the total loads on the suspended object 1 side and the counterweight 7 side are each 120 kg, and are balanced.

As described above, the weight of the chain 14 acting on the counterweight 7 changes with the lifting and lowering of the suspended object 1,
The load movement of the suspension rope 2 is absorbed.

As the chain 14, a roller chain whose weight can be freely selected according to the weight per unit length of the suspension rope 2 may be used. In addition, chain box 1
5 is made of a material, such as wood, which does not easily generate noise even when it comes into contact with the chain 14. When attaching the chain 14 to the counterweight 7, it is necessary to take care that the chain 14 does not hit the guide rail R due to the swing caused by the elevation.

The elevating device according to the third embodiment can be easily configured based on a conventional existing elevating device.

[0030]

As described above, in the lifting device according to the present invention, the spring is connected to either the counterweight or the suspended object, and the elastic force of the spring that changes as the suspended object is lifted causes the suspension line to be lifted. Since the movement of the load is absorbed, regardless of the position of the suspended object, the rope can be operated with a constant small force, and the load direction on the rope is not changed during lifting and lowering of the suspended object. For this reason, the lifting and lowering operation of the suspended object can be performed easily and safely without requiring special physical strength or skill.

A similar structure as described above may be adopted in which a chain whose lower end is grounded is connected to the counterweight so that the weight of the chain acting on the counterweight absorbs the load movement of the suspension rope accompanying the lifting and lowering of the suspended object. The effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of a suspended object lifting device according to the present invention;

FIG. 2 is a schematic diagram showing an operation state of the above.

FIG. 3 is a schematic view showing an operation state of a second embodiment of the suspended object lifting device according to the present invention;

FIG. 4 is a view showing a third embodiment of a suspended object lifting device according to the present invention;

FIG. 5 is a schematic diagram showing an operation state of the above.

FIG. 6 is a diagram showing a conventional suspended object lifting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Suspended object 2 Suspension line 7 Counterweight 9 Towline 12 Spring 14 Chain

Claims (2)

[Claims] 1. A stage lifting device for a stage, wherein a suspension rope for suspending a suspension is wrapped around a pulley and connected to a counterweight, and the suspension is raised and lowered in a direction opposite to the counterweight as the pulling rope is operated. A spring is connected to either the weight or the suspended object, and the elastic force of the spring absorbs the load movement of the suspension line between the suspended object side and the counterweight side accompanying the lifting and lowering of the suspended object. Stage lifting equipment. 2. A stage lifting / lowering device for a lifting / lowering device, wherein a suspension rope for suspending a suspension is wound around a pulley and connected to a counterweight, and the suspension is raised and lowered in a direction opposite to the counterweight as the pulling rope is operated. A chain whose lower end is grounded is connected to the weight, and the weight of the chain acting on the counterweight absorbs the load movement of the suspension rope between the suspended object side and the counterweight side accompanying the lifting and lowering of the suspended object. Stage lifting equipment