JPH047633Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a slack absorbing device, and more particularly to a slack absorbing device capable of absorbing slack caused by thermal expansion of power transmission lines and the like.

<Prior Art> In various technical fields, it may be necessary to control the slack of a wire that is stretched over the wire. For example, in the case of power transmission lines that connect power plants or substations, or between power plants and substations to supply electricity, they are However, it is necessary to tension the power transmission lines with an appropriate amount of slack in order to avoid excessive tension on the power lines. However, in order to ensure a safe distance between the minimum ground clearance part of the power transmission line and the ground, it is necessary to maintain a sufficiently large distance between the power transmission line and the ground to ensure the minimum ground clearance of the power transmission line. .

By the way, with the increase in power consumption in recent years,
As the load current of power transmission lines has increased, the amount of heat generated by the current has increased relatively. Therefore, the length of the power transmission line is further increased due to the increase in thermal expansion, and there is a possibility that the slack between the towers of the power transmission line may become excessive. Therefore, not only does the minimum ground height of the power transmission lines become lower and the distance from the ground becomes narrower, but also the problem arises that when the power lines are shaken by strong winds or earthquakes, the distance between the power lines becomes narrower.

Therefore, in order to ensure sufficient minimum ground clearance even when load current increases and excessive slack occurs due to thermal expansion, it is necessary to increase the height of the steel tower. Also, in order to prevent excessive slack,
It is good to make the power transmission line thicker in order to suppress the thermal expansion of the power line, but in this case, the weight of the power transmission line increases, so it is necessary to increase the strength of the steel tower.

<Problems to be solved by the invention> However, the problem arises that equipment costs increase due to replacement of power transmission lines and construction of steel towers.

In view of these problems of the prior art, the main purpose of the present invention is to provide a slack absorbing device that can easily absorb slack caused by thermal expansion of power transmission lines, etc., at low cost.

<Means for solving the problem> This purpose is to provide a slack absorbing device for automatically adjusting the tension of power transmission lines, etc., which is connected to a casing coaxially and integrally with the casing. supported first and second pulleys;
a first wire wound around a pulley;
a spring member provided between the free end of the second wire wound around the pulley and the casing, and generating a biasing force in a direction to pull out the second wire from the second pulley. and the spring member is oriented to tension the first wire such that the ratio of the effective winding diameter of the second pulley to the first pulley provides a substantially constant tension to the first wire. This is achieved by providing a slack absorbing device characterized in that the slack is gradually increased in accordance with the amount of deformation.

<Function> By doing this, when the wire is stretched due to thermal expansion, and the power transmission line, etc. that is stretched over it is stretched due to thermal expansion, the spring member will take up the slack of the power transmission line, etc. Since the first pulley can rotate in a direction that tensions the first wire, slack can be taken up. At this time, the spring force of the spring member will decrease depending on the amount of deformation, but
As the effective winding diameter of the second pulley, which is rotationally driven by a spring member, is rotated in a direction that tensions the wire with respect to the effective winding diameter of the first pulley connected to the first wire, Since the tension increases gradually, it is possible to prevent a decrease in tension on power transmission lines and the like.

<Embodiments> The present invention will now be described in detail with reference to specific embodiments with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing how a power transmission line is supported using a slack absorbing device based on the present invention, in which a wire-shaped power transmission line 2 is stretched between adjacent steel towers 1. An arm 3 extends horizontally at a predetermined height of the steel tower 1, and a pair of wire slack absorbers 4 are supported on both sides of the arm 3 by ropes 6 through insulators 5, respectively. There is. With this wire slack absorbing device 4, each steel tower 1
A power transmission line 2 between the two is supported at both ends via a clamp member 7, and is electrically connected via a jumper wire 8 stretched between both clamp members 7 of each steel tower 1. .

FIG. 2 is a cross-sectional view along the axial direction showing the entire wire slack absorbing device 4. As shown in FIG. As clearly shown in FIG. 2, L-shaped locking holes 12 are opened at symmetrical positions in the diametrical direction near the right end in FIG. 2 of the casing 11, which has a cylindrical shape with both ends open. Both free ends of a bar-shaped rope clamp 13 are engaged with both locking holes 12.
A hole 14 is bored in the center of the rope clamp 13, and the free end of the rope 6 described above is inserted through the hole 14. Note that the free end of the rope 6 is reversed after being inserted into the hole 14, and a crimp sleeve 15 is caulked to the free end to prevent the rope 6 from coming off. In addition, rope clamp 13
Both free ends of the rope clamp 13 are bent at substantially right angles along the outer peripheral surface of the casing 11, thereby preventing the rope clamp 13 from falling off.

A disk-shaped end plate 16 is fixed to the left end of the casing 11 in FIG. 2 by, for example, welding in order to close the open end of the casing 11 to prevent rain or dust from entering the casing 11. There is. Further, a plate-shaped wall portion 17 is formed in the vicinity of the left end of the casing 11 in FIG. 2 so as to form an annular shape along the inner peripheral surface of the casing 11.

A cylindrical cylinder 18, which will be described later, is coaxially received on the right end side of the wall portion 17 of the casing 11 in FIG. A plate-shaped end plate 19 is fixed by, for example, welding. End plate 19 and wall part 1
7 is a compression coil spring 2 as a spring member.
1 surrounds the outer periphery of the cylinder 18,
It is inserted in a compressed state. Furthermore, cylinder 1
At the periphery of the bottom wall 22 at the left end in FIG. 8 of FIG.
3 are fixed so as to face each other and extend to the left in FIG. 2 along the axial direction. Both ends of a wire clamp plate 24 are fixed to both free ends of the pair of extension brackets 23, and the wire clamp plate 24 is provided at a position slightly eccentric to the rear side in FIG. .

A pulley device 25 is rotatably supported between the wall 17 in the casing 11 and the end plate 16 via a bearing 27 on a shaft 26 fixedly provided in the diametrical direction of the casing 11. ing. FIG. 3 is a sectional view taken along the - line in FIG. 2, and as is well shown in FIGS.
5 is formed with a perfect circular pulley part 28 as a second pulley which is not concentric with the shaft 26 and whose effective winding diameter part is formed into a perfect circle, and an effective winding diameter part whose diameter is continuously reduced. Variable diameter pulley part 2 as a first pulley
9 are integrally formed with each other. In addition, regarding the outer periphery of this variable diameter pulley part 29, there is a part 31 having the same outer diameter as the perfect circular pulley part 28, and a part 31 that extends counterclockwise (arrow A) in FIG. 2 from that part 31. A variable diameter portion 32 whose diameter is continuously reduced at a predetermined rate is formed.

One end of the second wire 33 is screwed to the perfect circular pulley portion 28 and is wound along the direction of arrow B in FIG. The wire clamp plate 24 described above
is combined with Therefore, the end plate 1 of the cylinder 18
The biasing force of the compression coil spring 21 acting on the pulley 9 acts to rotate the perfect circular pulley portion 28 in the direction of arrow B in FIG. Further, the other end of a first wire 34 whose one end is connected to the end of the power transmission line 2 via the clamp member 7 outside the casing 11 is screwed to the variable diameter pulley portion 29. At the same time, the other end is wound so as to be drawn out in the direction of arrow A in FIG.

A guide roller 36 is provided near the end plate 16 of the casing 11, and a portion of the first wire 34 extending toward the outside of the casing 11 is provided near the end plate 16 of the casing 11.
It is rotatably supported by a support shaft 37 fixed to the casing 11 so as to be coaxial with the casing 1 . Note that outside the casing 11, the first wire 34 guided by the guide roller 36 is
It is fed out through a hole 38 formed in the center of the end plate 16. In this way, casing 1
The end of the first wire 34 extending toward the outside of the casing 1 is connected to the clamp member 7 as described above. Since it is regulated, it is possible to prevent the axis of the casing 11 from tilting with respect to the direction of the tension acting on the first wire 34.

A clamp portion 39 for clamping the end of the power transmission line 2 by caulking is formed on the clamp member 7, and a U-shaped bolt 35 is attached to a flange portion 41 formed integrally with the clamp portion 39. ing. An annular end portion of the first wire 34 is connected to this U-shaped bolt 35 . Note that the power transmission line 2 is firmly caulked by the clamp portion 39, and the core wire 43 at the free end of the power transmission line 2 is further caulked with a crimp sleeve 42, so that it is securely prevented from coming off. Further, a jumper socket portion 44 is integrally formed on the clamp member 7 so as to extend from the clamp portion 39, and the end portion of the jumper wire 8 described above is held in the jumper socket portion 44 by caulking.

A disk-shaped piston 45 is received in the cylinder 18 so as to be slidable in the axial direction. A screw hole 46 is coaxially formed in the center of the piston 45, and one end of a support rod 48 is screwed into the screw hole 46, so that the piston 45 and the support rod 48 are coaxial and integral with each other. ing. Note that the other end of this support rod 48 is connected to the rope clamp 13 described above.
It is pivotably and centrally supported within a boss portion 51 formed at the center of the shaft.

In this way, the piston 45 is fixed in the axial direction by the support rod 48, and as the power transmission line 2 expands and contracts due to thermal expansion as power consumption increases or decreases, the cylinder 18 moves as shown in FIG. It will reciprocate in both directions indicated by arrow C.

The first cylinder chamber 53 on the left side of the piston 45 in FIG. 2 and the second cylinder chamber 54 on the right side thereof.
The insides of the cylinders are filled with atmospheric air at normal pressure, but an orifice 52 is bored in the piston 45 along the axial direction, and both cylinder chambers 53 and 54 communicate with each other via the orifice 52. ing. A bisected annular sliding member 55 is fixed and coaxially fitted to the outer circumference of the piston 45 by a garter spring 56 that is elastically fitted to the outer circumferential end surface of the sliding member 55. When reciprocating, the atmosphere in one of the cylinder chambers 53, 54 is prevented from leaking from the outer periphery of the piston 45 to the other.

Furthermore, the first cylinder chamber 53 of the orifice 52
A plate-shaped adjustment plate 57 is fixed to the side with bolts, for example, and is provided with its end facing the opening of the orifice 52. By adjusting the adjustment plate 57 to increase or decrease the opening area of the orifice 52, the flow rate of the atmosphere passing through the orifice 52 can be adjusted, so that the damping force against the reciprocating motion of the cylinder 18 can be suitably adjusted. In addition, the end plate 19 also has a garter spring in which a bisected annular sliding member 58 is elastically fitted on the outer peripheral end surface in order to prevent atmospheric leakage from the sliding contact portion with the support rod 48. 59 and are coaxially fitted.

Further, a convex piece 60 is provided on the outer peripheral edge of the end plate 19 so as to extend outward in the radial direction of the casing 11 from a slot (not shown) formed in the casing 11 along the axial direction. ing. This convex piece 60 allows the amount of displacement of the end plate 19 to be visually observed, and the spring biasing position of the compression coil spring 21 at the time of installation can be easily adjusted.

The wire slack absorbing device 4 configured in this manner is in the state shown in FIG. 2 when no current flows through the power transmission line 2, and when the maximum allowable current flows through the power transmission line, Since the power transmission line 2 thermally expands due to heat generation, the cylinder 18 moves to the position shown by the imaginary line in FIG. At this time, in this embodiment, the compression coil spring 21 is expanded as the cylinder 18 moves, so the spring biasing force is reduced, but at the same time, the pulley device 25
rotates in the direction of arrow B, the first wire 34 connected to the power transmission line 2 is wound up by the variable diameter portion 32 of the variable diameter pulley portion 29, and the winding force is used as the effective winding diameter. will increase as the radius of the variable diameter portion 32 decreases. The spring biasing force decreases according to the amount of deformation on the extension side of the compression coil spring 21, which is the direction in which the second wire 33 is pulled out. The diameter reduction rate of the variable diameter portion 32 in this embodiment is determined in order to gradually increase the effective winding diameter of the perfect circular pulley portion 28 relative to the variable diameter pulley portion 29 so as to give the following.

In the pulley device 25 of this embodiment, the spring biasing force of the compression coil spring 21 is applied to the perfect circular pulley part 28, and the tensile force to the power transmission line 2 is applied by the variable diameter pulley part 29. The combination of both pulley parts is not limited to this, but the power transmission line 2 can be pulled by a perfect circular pulley part that is integrated with the pulley part by applying a spring biasing force to the pulley part whose diameter is continuously enlarged, for example. Good too.

Further, as described above, by providing the damper mechanism including the piston 45 and the cylinder 18, when the power transmission line 2 shakes due to wind or an earthquake, for example, the vibration can be suitably damped by the damper mechanism. can. Therefore, even if vibration occurs in the power transmission lines 2 due to some external factor, it is possible to prevent the distance between the power transmission lines 2 and the minimum ground clearance from decreasing significantly.

In this embodiment, a compression coil spring 21 is used to apply a spring biasing force to the power transmission line 2.
However, not only a compression coil spring may be used, but also a tension coil spring may be used, and the shape of the spring is not limited.

<Effects of the invention> As described above, according to the invention, when elongation occurs due to thermal expansion in a power transmission line, etc., the second wire is pulled out from the second pulley in the direction in which the first wire is wound. As both pulleys rotate in this direction, the biasing force of the spring member decreases, but by appropriately setting the ratio of the effective winding diameters of both pulleys, the tension of the first wire can be kept approximately constant. It can automatically absorb slack due to stretching of power transmission lines, etc.
Therefore, there is no need to replace or replace the power transmission line or modify the wire support structure in response to an increase in load, so the equipment cost can be reduced, which is extremely effective.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a state in which a power transmission line is supported by a wire slack absorbing device according to the present invention. FIG. 2 is a cross-sectional view along the axial direction showing the entire wire slack absorbing device based on the present invention. Third
The figure is a sectional view taken along the - line in FIG. 2. 1... Steel tower, 2... Power line, 3... Arm, 4
...Wire slack absorber, 5...Insulator, 6...
Rope, 7... Clamp member, 8... Jumper wire, 11... Casing, 12... Locking hole, 13
...rope clamp, 14 ... hole, 15 ... crimp sleeve, 16 ... end plate, 17 ... wall, 18 ...
... Cylinder, 19 ... End plate, 21 ... Compression coil spring, 22 ... Bottom wall, 23 ... Extension bracket,
24...Wire clamp plate, 25...Pulley device, 26...Shaft, 27...Bearing, 28...Perfect round pulley part, 29...Variable diameter pulley part, 31...Part, 32...Variable diameter part , 33... Second wire, 34... First wire, 35... U-shaped bolt, 36... Guide roller, 37... Support shaft, 3
8... Hole, 39... Clamp part, 41... Flange part, 42... Crimp sleeve, 43... Core wire, 4
4... Jumper socket part, 45... Piston,
46... Rod, 48... Support rod, 51... Boss portion, 52... Orifice, 53... First cylinder chamber, 54... Second cylinder chamber, 55... Sliding material, 56... Garter spring, 57...adjustment plate, 58...sliding material, 59...garter spring, 60...convex piece.

Claims (1)

[Claims for Utility Model Registration] A slack absorbing device for automatically adjusting the tension of a power transmission line, etc., comprising: a casing; and a first and second second tube coaxially and integrally supported by the casing; a pulley, a first wire wound around the first pulley, a second wire wound around the second pulley, and a wire provided between the free end of the second wire and the casing; a spring member that generates a biasing force in a direction to pull out the second wire from the second pulley, and the ratio of the effective winding diameter of the second pulley to the first pulley is such that the first wire The slack absorbing device is configured to gradually increase the amount of deformation of the spring member in a direction that tensions the first wire so as to apply a substantially constant tension to the first wire.