JP2003176098A - Hoist unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hoist unit capable of reducing the burden of execution of works, improving security in maintenance work, and miniaturizing a driving device and a tensioner device for absorbing the looseness of a wire rope together. <P>SOLUTION: The hoist unit is provided with a ramp 101 and a balance weight 102, which are interlocked with each other and ascending and descending in the reverse direction each other. The ramp 101 and the balance weight 102 are fixed to wire ropes 103a and 103b in the form of a loop rolling and circulating over upper driven pulleys 109a, 109b and lower driving pulleys 105a, 105b respectively. The upper driven pulleys 109a and 109b are independent mutually and rotatably supported by a driven shaft 108. The lower driving pulleys 105a and 105b are fixed to the same driving shaft 104 which is driven by a driving device 106. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for lifting and lowering a heavy object from one side to the other between conveying tracks having a height difference, and for loading and unloading an object to be conveyed. It relates to a lifting device used for the purpose. 2. Description of the Related Art Conventionally, as shown in FIG. 2, an upper drive type lifting device installed in a distribution center, a distribution center, a factory, etc., has a lifting table 201 and a balance weight 202, such as a chain or a belt. The drive shaft 2 is connected to each other by
It is suspended in a fishing bottle manner on a drive wheel 205 such as a chain wheel or a pulley fixed to 04. A drive device 206 such as an electric motor is connected to the drive shaft 204 so as to move up and down in opposite directions. In such an elevating apparatus 200, when the weight of the balance weight 202 is W1, the weight of the elevating table 201 is W2, and the weight of the conveyed object 207 placed on the elevating table 201 and conveyed up and down is w. , W1 = W2 + w, the load on the drive wheel 205 is balanced, and the load on the drive device 206 can be minimized. Actually, the weight w of the transported object 207 changes each time. Therefore, when the maximum weight of the transported object is W3, W
The weight W1 of the balance weight 202 is determined so that 1 = W2 + 0.5 × W3, the load applied to the driving device 206 is reduced, and the capacity and power consumption of a motor or the like used as the driving device are reduced. I have. In this case, both the balance weight side 203a and the lifting platform side 203b always exert a vertical downward pulling force on the rope 203 with the drive wheel 205 as a boundary, so that the rope 203 becomes slack during the vertical transportation. There is no. [0004] Further, in a lower drive type elevating device 300 as shown in FIG. 3, a drive wheel 305 such as a pulley or a pulley supported by a drive shaft 304 and a drive wheel 305 supported by a driven shaft 308. The lift table 301 and the balance weight 302 are connected to a rope 303 such as a chain or a belt of a loop circulated between a driven wheel 309 such as a wheel and a pulley so as to move up and down in an opposite direction to each other. . A drive device 306 such as an electric motor is connected to the drive shaft 304 so as to move up and down in opposite directions. [0005] However, the conventional lifting device as described above has the following problems. In the upper drive type elevating device 200 as shown in FIG. 2, since the drive device 206 is located on the upper portion, the work load at the time of construction is increased, and the maintenance work of the drive device 206 is performed at a high place, which is dangerous. Was. Further, in the lower drive type lifting device 300 as shown in FIG. 3, since the drive device 306 can be installed below the lifting device, the work load at the time of construction is reduced and the safety at the time of maintenance work is enhanced. I was able to. However, since the rope 303 has a loop shape, the weight W1 of the balance weight 302, the weight W2 of the lift 301,
Due to the weight w of the transported object 307 and the total weight of the weight of the rope 303, the rope 303 is elongated, and the lower rope 303c, 3c
Since 03d is loosened, a strong tensioner 310 is required to absorb it. Further, similarly to the above-described upper drive type lifting device 200, the weight of the lifting table
2. When the maximum weight of the transferred object 307 is W3, W
When the weight W1 of the balance weight 302 is determined so that 1 = W2 + 0.5 × W3, and the load applied to the driving device 306 is reduced, the tensioner 310 has a maximum (that is, the load 307 is loaded). (When not carried out), a tensile force equal to or more than 1/2 of the weight W3 of the transferred object 307 is applied, so that a stronger tensioner capable of withstanding the tensile force is required. [0007] Further, by making the weight W2 of the lift table 301 sufficiently larger than the weight W1 of the balance weight 302, the force applied to the ropes 303 always moves in one direction regardless of the weight of the load 307. By doing so, it is possible to prevent a tension force from being applied to the tensioner 310. In that case, however, the weight W1 of the balance weight 302, the weight W2 of the lift 301, and the load 307 Since the sum of the weights W3 is not balanced and a large load is applied to the driving device 306, a strong driving device is required. Accordingly, an object of the present invention is to provide an elevating device which reduces the work load, enhances safety in maintenance work, and reduces both the driving device and the tensioner device for absorbing slack of the cable. Is to do. [0009] In order to achieve the above object, the present invention relates to a lifting apparatus provided with a lifting table and a balance weight which move up and down in a direction opposite to each other along a mast. The balance weight is fixedly mounted on a loop-shaped rope circulated around another upper driven wheel and a lower driving wheel, and the upper driven wheel is rotatable independently of each other on a driven shaft. The lower drive wheels are supported on the same drive shaft, and are driven by a drive device. According to the present invention, since the balance weight and the elevator are fixed to different loop-shaped ropes, respectively, the ropes are always attached to each of the ropes regardless of the weight of the load. While the pulling force acts in the same direction, only the weight of the balance weight or the weight of the elevator, the weight of the transported object, and the weight of the own weight of each rope are applied to the rope. For this reason, the tensioners installed on each cable can be small enough to absorb the slack of each cable. Also, the weight W1 of the balance weight and the weight W2 of the lift can be arbitrarily determined without any other restrictions.
For example, the weight W1 of the balance weight and the weight W of the elevator
2 and the maximum weight of the transferred object W3 (that is, the weight of the transferred object is 0.5 × W3 which is half of W3 on average) is determined so as to satisfy W1 = W2 + 0.5 × W3. And the load on the driving device can be reduced. An embodiment of the present invention will be described below based on Embodiment 1 with reference to FIG. FIG. 1 is a diagram illustrating a mechanism of the lifting device 100 according to the first embodiment. The elevating device 100 includes an elevating platform 101 and a balance weight 102 that move up and down in a direction opposite to each other along a mast (not shown), and the balance weight 102 and the elevating platform 101 are each provided with a different upper support. Driving wheels 109a, 109b and lower drive wheels 105a,
A loop-like rope 103a, 1 circulated around 105b,
03b. And the upper driven wheel 10
9a and 109b are driven shafts 1 rotatable independently of each other.
08 and the lower drive wheels 105a, 105b
Are fixed to the same drive shaft 104, and the drive shaft 1
04 is driven to rotate by the driving device 106. [0013] The loop-shaped ropes 103a and 103b include:
Spring-type tensioners 110a and 110b for absorbing slack due to elongation are respectively provided with balance weights 102.
And it is provided immediately below the fixed position of the lifting platform 101.
The ropes 103a and 103b are always in one direction, that is, the balance weight 102, the driving wheel 105a, and the lift 1 regardless of the weight of the load 107 loaded on the lift 101.
01 and the drive wheel 105b
Since a force is applied in a direction in which the tensioners are slackened, no tension is applied to the tensioners 110a and 110b.
Also, the weight W1 of the balance weight 102 or the weight W of the lift 101 is attached to each of the ropes 103a and 103b.
Since only the sum of 2 and the weight w of the transferred object 107 is added,
The use of a thin cable becomes possible, and the tensioner 110 is used.
Also, a and 110b are small enough to absorb the slack of each cord. Further, since the weight W1 of the balance weight and the weight W2 of the elevator can be determined without any other restrictions, the maximum weight W3 of the transferred object (ie, on average, the weight of the transferred object) 0.5 x W3) which is half of the weight,
By determining so as to satisfy the relationship of W1 = W2 + 0.5 × W3, the forward and reverse forces acting on the drive shaft are balanced, and the load on the drive device can be reduced. The cables 103a and 103b are not particularly limited, and a known power transmission medium such as a chain or a belt can be used. Further, the drive wheels 105a, 1
The 05b and the driven wheels 109a and 109b are not particularly limited, either.
A pulley or the like can be used. In this embodiment, the tensioners 110a, 11
Although a spring-type tensioner is used as 0b, the invention is not limited to this, and a known tensioner such as a hydraulic tensioner can be used. Next, a second embodiment which is another embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a front view of the lifting device 400 according to the second embodiment, and FIG. 5 is a side view thereof. In this elevating device 400, a balance weight 402 and an elevating table 401 are fixed to two right and left ropes 403a and 403b, respectively. The ropes 403a and 403b are respectively connected to different upper driven wheels 40.
9a, 409b and lower drive wheels 405a, 405b are looped and circulated. The upper driven wheels 409a and 409b are rotatably supported by a driven shaft 408 independently of each other, and are driven by the lower driven wheels 405a and 405.
b are fixed to the same drive shaft 404, and the drive shaft 404 is driven by a drive device 406. The balance weight 402 and the elevator 401
To two right and left ropes 403a, 403a and 4
Since the cables are fixed at the positions 03b and 403b, the load applied to each cable is halved, and a thin cable can be used.
Therefore, the load on the rope is reduced by the weight of the rope, and the size of the tensioner is further reduced. Further, it is possible to reduce the left and right swing during the vertical transportation as compared with the case where the balance weight and the lifting platform are driven up and down by one rope, and it is possible to perform the stable vertical driving. The other configuration is the same as the configuration of the first embodiment, and thus the detailed description is omitted. In the first and second embodiments, when the weight W1 of the balance weight and the weight W2 of the elevator are set to the maximum weight W3 of the load, W1 = W2 + 0.5 × W3.
Although it is determined to satisfy the relationship of W3, usually, it is needless to say that the relationship of W1 = W2 + w3 is satisfied when the weight of the transported object to be lifted and lowered is almost constant (w3). By determining the weight W1 of the balance weight and the weight W2 of the elevator, the load on the driving device can be further reduced. Further, the weight of the balance weight W2 is always changed to W1 = W2 + according to the variation of the weight w3 of the transported object.
By adjusting so as to satisfy the relationship of w3, it is possible to always minimize the load applied to the driving device. As described above, according to the present invention,
The drive device can be installed at the lower part of the lifting / lowering device, and the work during construction is reduced. In addition, maintenance work after installation can be performed safely. Further, since the balance weight and the lifting platform are fixed to different loop-shaped ropes, respectively, the load on the ropes is reduced, and the respective weights are independent of the weight of the transported object. Since the same direction of force always acts on the cable,
No tension is applied to the tensioner for absorbing slack, and the size of the tensioner can be reduced. Further, since the weight of the balance weight and the weight of the elevator can be arbitrarily determined without any other restrictions, the relationship between the weight of the balance weight and the weight of the elevator can be optimized, and the driving device can be used. It is possible to reduce the capacity and power consumption of a motor and the like to be used.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram illustrating a mechanism according to a first embodiment of the present invention. FIG. 2 is a diagram for explaining a mechanism of a conventional upper drive type lifting device. FIG. 3 is a view for explaining a mechanism of a lower drive type lifting device which is a conventional technique. FIG. 4 is a front view of a lifting device according to a second embodiment of the present invention. FIG. 5 is a side view of the elevating device shown in FIG. [Description of Signs] 100, 200, 300, 400 Lifting device 101, 201, 301, 401 Lifting table 102, 202, 302, 402 Balance weight 103, 203, 303, 403 Cable 104, 204, 304, 404 Drive shaft 105, 205, 305, 405 Driving wheels 106, 206, 306, 406 Driving devices 107, 207, 307 Conveyed objects 108, 308, 408 Driving shafts 109, 309, 409 Driving wheels 110, 310 Tensioners

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Shinya Tokunaga             2-1-1, Shiromi, Chuo-ku, Osaka-shi, Osaka             Tsubakimoto Chain Co., Ltd.

Claims (1)

Claims: 1. An elevating device having a lifting platform and a balance weight that move up and down in a direction opposite to each other along a mast, wherein the lifting platform and the balance weight are provided with separate upper driven wheels and The lower driven wheel is fixed to a loop-shaped rope circulated around the lower driving wheel, the upper driven wheel is supported on a driven shaft rotatable independently of each other, and the lower driving wheel is the same as each other. An elevating device fixed to a drive shaft, wherein the drive shaft is driven by a drive device.