JPH0851710A - Compression anchor clamp and prefabricated wire - Google Patents

Abstract

PURPOSE:To protect a prefabricated wire against plastic deformation caused by the bending moment acting on the prefab wire at the time of passing through a metal wheel. CONSTITUTION:The steel clamp 22 of a compression anchor clamp 21 comprises a steel sleeve part 24, a corrugated part 25, an intimate contact part 26, and an anchor part 27 integrally wherein the steel sleeve part 24 is provided integrally, on the forward end side thereof, with a steel sleeve extension part 32. The steel sleeve extension part 32 has a length exceeding the middle part M of the compression anchor clamp having overall length L and provided with a hole being fitted over the inner layer part (exposed inner layer part) which is exposed by stripping an aluminum conductor steel reinforced(ACSR). The ACSR is clamped, at the opposite ends thereof, with the compression anchor clamps 21 to produce a prefab wire. The steel core of the wire is inserted into the hole of the steel sleeve part 24 is then compressed over the steel core while fitting the exposed inner layer part in the hole of the steel sleeve extension part 32. Subsequently, an aluminum sleeve 23 is compressed over the steel clamp 22 and the aluminum wire part of the wire.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compression type detention clamp used for retaining an electric wire such as a transmission line made of a steel core aluminum stranded wire in a tension tower and a prefabricated electric wire having the detention clamp.

[0002]

2. Description of the Related Art When a steel core aluminum stranded wire having a two-layer structure of a steel core that is a tension member and an aluminum stranded wire that is a current path is used as an electric wire for an overhead power transmission line, etc. In order to retain the (electrical wire) to the tension tower, a compression type strain clamp consisting of a steel clamp and an aluminum sleeve is used, corresponding to the two-layer structure of steel core aluminum stranded wire. A general compression type detention clamp of this type has a so-called JEC type structure in which a lug portion for connecting a jumper socket is largely projected from an end portion of an aluminum sleeve in a substantially perpendicular direction.

By the way, for the purpose of labor saving of the overhead line work, the span of the steel tower to be erected is precisely measured in advance.
A prefabricated wire is prepared by precisely measuring the length of the wire that should be erected in the factory, taking into account the sag of the wire, and compressing and fixing compression-type detention clamps at both ends of the wire to form a prefabricated wire. The overhead wire construction method is known. At the time of extending this prefabricated wire, a wire rope is connected to the compression type detention clamp at the end of the wire, and the wagon suspended on the steel tower arm is passed through. Since it is difficult to pass the money wheel due to the lug portion, as shown in FIGS. 7 and 8, a so-called money wheel passing type compression type in which the lug portion 9 is provided along the aluminum sleeve 3 and does not project so much. The detention clamp 1 is used. In addition, as shown in the figure, in order to reduce the damage of the wire due to the sharp bend of the wire at the clamp opening (the left end in Fig. 7) when passing through the gold wheel, the total length of the compression type detention clamp is set electrically and mechanically. It has a structure that is as short as possible within the range of satisfying various performances. The details of the conventional compression type detention clamp 1 will be described. 2 is a steel clamp, 3 is an aluminum sleeve, and the steel clamp 2 is
In order to achieve watertightness between the corrugated portion 5 for firmly connecting the steel sleeve portion 4 and the aluminum sleeve 3 which are compressed and fixed on the exposed steel core portion of the wire end, and the steel clamp 2 and the aluminum sleeve 3. It has a structure in which the taper close contact portion 6 and the retaining portion 7 for retaining the steel tower are integrally formed, while the aluminum sleeve 3 extends over the outer periphery of the aluminum wire portion of the electric wire and the portion other than the retaining portion 7 of the steel clamp 2. It consists of an aluminum sleeve body 8 that is compressed and fixed, and a plate-like lug portion 9 that is integrally provided along the aluminum sleeve body 8 on the retaining end side (right side in FIG. 7) of the aluminum sleeve body 8. There is.
The compression type detention clamp 1 is shortened to about 80% of the length of the JEC type compression detention clamp described above.

Then, the compression type detention clamp 1 is compressed and fixed to both ends of a precisely sized electric wire to form a prefabricated electric wire. At this time, the aluminum sleeve 3 is previously inserted into the outer circumference of the aluminum wire portion of the electric wire. Then, after the steel sleeve portion 4 of the steel clamp 2 is compressed and fixed on the exposed steel core of the wire end portion, the aluminum sleeve 3 is compressed and fixed over the outer circumference of the steel sleeve portion 4 and the outer circumference of the aluminum wire portion. The steel clamp 2 and the aluminum sleeve 3 are integrated. After the prefabricated electric wire is extended, a jumper socket 11 having a bifurcated tip is fitted into the lug portion 9 as shown by a chain double-dashed line in FIGS.

The above-mentioned conventional compression type detention clamp 1 for passing through a gold wheel is designed from the viewpoint of simply satisfying the electrical and mechanical performance of the compression type detention clamp. Therefore, as shown in FIG. 2, the steel sleeve portion 4 is the entire length of the compression type detention clamp 1 (aluminum sleeve 3
From the mouth to the center of the connecting hole 7a of the pulling part 7) L
It had a length that did not reach the central portion M of the.

[0006]

In the work of extending the prefabricated electric wire in which the compression type detention clamp 1 is compressed and fixed as described above, as shown in FIG.
As shown in FIG. 10, when passing through the gold wheel 12, the compression type detention clamp 1 moves the electric wire 13 and the wire rope 1
Since the vertical component force T _V due to the wire drawing tension T of 4 is received, it is bent from both sides around the central portion M of the compression type detention clamp 1. In this case, the location where the maximum bending moment occurs is the central portion M, while the tip of the steel clamp 2 has a length that does not reach the central portion of the compression type detention clamp 1 as described above, that is, the central portion. Since the portion from M to the electric wire 13 side is only the aluminum sleeve 3 having low strength, the aluminum sleeve 3 may be plastically deformed and bent due to the drawing tension depending on the drawing tension and the catenary angle. For this reason, when using the compression-type strain-tightening clamp 1 of this type that passes through the gold wheel, it is necessary to set restrictions on the wire tension and the catenary angle. Also, in order to prevent bending of the compression type detention clamp 1 due to plastic deformation, the main part is made of special steel with high strength and the wire side part is compressed into a rubber-made clamp protector to protect the wire from bending. A method of accommodating the mold retracting clamp 1 and allowing it to pass through the gold wheel has also been put into practical use. However, this method requires complicated work for mounting and removing the clamp protector, and the removal work is performed by connecting the clamp protector to the upper part of the steel tower. Since it has to be performed at the tip of the Zhang insulator series and is not easy, there is a drawback that the number of man-hours increases significantly.

The present invention has been made to solve the above-mentioned conventional drawbacks, and it is possible to improve the strength of the compression type detention clamp against the maximum bending moment due to the vertical component force of the wire drawing tension when passing through the gold wheel. An object of the present invention is to provide a compression type detention clamp that can prevent bending of the compression type detention clamp due to plastic deformation without using a clamp protector, and a prefabricated electric wire including the compression type detention clamp.

[0008]

A compression type detention clamp of the present invention which solves the above-mentioned problems is provided with a steel sleeve portion which is compressed and fixed on the outer circumference of a steel core of an electric wire end portion made of a steel core aluminum stranded wire, and the electric wire. A compression-type detention clamp comprising: a steel clamp having at least a detention part for retaining the wire; and an aluminum sleeve that is compression-fixed over the outer circumference of the aluminum wire part of the electric wire and the part of the steel clamp excluding the detention part. The steel clamp has a tubular shape that is concentric with the steel sleeve portion, and is equipped with a steel sleeve extension portion that is fitted around the outer periphery of any aluminum wire inner layer portion of the electric wire except the outermost layer of the aluminum wire portion. Is characterized in that it extends at least to a position beyond the central part of the entire length of the compression type detention clamp.

[0009]

[Operation] When a prefabricated electric wire having the above-structured compression type detention clamp compressed and fixed to an electric wire is extended, when the compression type detention clamp passes through the metal sheave, the compression type detention clamp uses the extension tension of the wire and the wire rope. The maximum bending moment is generated in the central part due to the vertical component force due to. However, in this central part there is a steel sleeve extension of the steel clamp,
Since the steel sleeve extension with high strength bears the maximum bending moment, bending due to plastic deformation of the aluminum sleeve can be prevented.

[0010]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a front view of a compression type detention clamp 21 according to an embodiment of the present invention, and FIG. 2 is a right side view of the same. FIG. 3 is a front view showing only a later-described steel clamp 22 of the compression type detention clamp 21. The compression type detention clamp 21 is composed of a steel clamp 22 and an aluminum sleeve 23. The steel clamp 22 has a hole 2 for inserting a steel core of an electric wire.
4a, a steel sleeve portion 24 that is compressed and fixed on an exposed steel core of an electric wire end portion made of a steel core aluminum stranded wire, a corrugated portion 25 for firmly coupling the aluminum sleeve 23, and a steel clamp 22. The structure in which the taper-shaped contact portion 26 for achieving water-tightness with the aluminum sleeve 23 and the detention portion 27 for retaining the same in the steel tower are integrally provided is the same as the conventional one. At the tip of the portion 24, a steel sleeve extension portion 32 is integrally provided, which has a cylindrical shape concentric with the steel sleeve portion 24 and is fitted on the outer periphery of any aluminum wire inner layer portion of the electric wire excluding the outermost layer of the aluminum wire portion, The steel sleeve extension 32 extends at least to a position beyond the central portion M of the compression type detention clamp full length (distance from the mouth of the aluminum sleeve 23 to the center of the connecting hole 27a of the detention portion 27) L. The inner diameter of the hole 24a of the steel sleeve portion 24 is large enough to allow the steel core to be inserted, but the inner diameter of the through hole 32a of the steel sleeve extension portion 32 is equal to that of the aluminum wire portion of the steel core aluminum stranded wire described later. Since it is necessary to fit the exposed inner layer portion, it is made slightly larger than the outer diameter of this exposed inner layer portion, and the outer diameter is almost equal to the outer diameter of the wire. In this way, the steel sleeve extension 32 can secure an outer diameter equivalent to the outer diameter of the electric wire, so that the section modulus of the steel sleeve extension 32 can be set large. The structure of the aluminum sleeve 23 is basically the same as the conventional one. The aluminum wire portion of the electric wire and the detention portion 2 of the steel clamp 22 are basically the same.
7. A cylindrical aluminum sleeve main body 28 that is compressed and fixed over the outer periphery of the portion other than 7, and a plate-like lug portion 29 integrally provided along the aluminum sleeve main body 28 on the holding end side of the aluminum sleeve main body 28. It consists of
A taper portion 28a is formed near the tip of the aluminum sleeve body 28, and the lug portion 29 has a jumper socket 1a.
A connection hole 29a for connecting 1 is formed. Also,
In order to increase the strength of the compression type detention clamp itself, the compression type detention clamp 21 has the outer diameter of the aluminum sleeve body 28 and the steel sleeve portion 24 of the steel clamp 22 set to the conventional JEC type compression detention clamp. Compared with the clamp,
It is about 1.4 to 1.8 times.

FIG. 4A shows the compression type detention clamp 21.
FIG. 3 is a vertical cross-sectional view showing a step-peeling structure of an electric wire 31 made of a steel core aluminum stranded wire which is compressed and fixed. The same figure (b) is a right side view of the same figure (a). As shown in the figure, the electric wire 31 has an aluminum wire portion 31b composed of, for example, three layers on the outer circumference of the steel core 31a, but in the illustrated example, the first and second layers are formed from the inner layer side of the aluminum wire portion 31b. The eye is cut and removed so that the exposed length of the steel core 31a of the electric wire 31 is almost equal to the length of the hole 24a of the steel sleeve portion 24, and the outermost layer is the cut end portion of the first and second layers. It is cut and removed so that the length from the position to the cut end position of itself is almost equal to the length of the through hole 32a of the steel sleeve extension 32, and the outer periphery of the second layer of the inner layer portion is almost the same as the through hole 32a. The exposed inner layer portion 31c has the same length. Regarding the material of each part, it is preferable that the steel clamp 22 is made of mild steel, and the aluminum sleeve 22 is made of an electric aluminum casting, an aluminum pipe or an aluminum rod.

When the compression type detention clamp 21 is compressed and fixed to the electric wire 31, the aluminum sleeve 23 is connected to the electric wire 3.
1, while inserting the steel core 31a of the electric wire 31 into the hole 24a of the steel sleeve portion 24 of the steel clamp 22 in a state of being slidably inserted into the aluminum wire portion 31b of No. 1 and exposing the exposed inner layer portion 3
1c is fitted in the through hole 32a of the steel sleeve extension 32, and then the steel sleeve 24 is compressed to
After compressing and fixing 4 onto the steel core 31a, the aluminum sleeve 2
3 is slid on the outer circumference of the steel clamp 22 to cover the outer periphery of the aluminum wire portion 31b and the outer circumference of the portion of the steel clamp 22 excluding the towing portion 27, and compress the steel clamp 2
2 and the aluminum sleeve 23 are integrated. As described above, the compression type detention clamp 21 is attached to both ends of the electric wire 31 cut to a fixed length.
A prefabricated wire can be obtained by compressing and fixing. After the prefabricated electric wire is extended, the jumper socket 11 having a bifurcated tip is fitted into the lug portion 29 as shown by a chain double-dashed line in FIGS.

As shown in FIG. 5, when the prefabricated electric wire 33, in which the compression type detention clamp 21 is compressed and fixed to both ends of the electric wire 31 in the above-described manner, is extended, the compression type detention clamp 21 causes the gold wheel 1 to move.
When passing through 2, the compression type detention clamp 21 is connected to the electric wire 31 and the wire rope 14 as described in FIG.
The maximum bending moment is generated in the central portion M by receiving the vertical component force T _V due to the wire drawing tension T of. However, since the steel sleeve extension 32 of the steel clamp 22 is present in the central portion M and the steel sleeve extension 32 having high strength bears the maximum bending moment, the bending due to the plastic deformation of the aluminum sleeve 23 can be prevented. . Further, since the steel sleeve extension 32 can secure the outer diameter equivalent to the outer diameter of the electric wire, the section modulus of the steel sleeve extension 32 can be set to be large, and therefore the strength of the steel sleeve extension 32 can be increased. In this respect also, the deformation of the aluminum sleeve 23 can be effectively prevented. Therefore, it is not necessary to use a clamp protector as in the past.

FIG. 6 shows another embodiment of the steel clamp 22A in the compression type detention clamp of the present invention. This steel clamp 22A is obtained by omitting the corrugated portion 25 of the steel clamp 22 shown in FIG. 3, and is otherwise the same as the steel clamp 22 of FIG. That is, in the present invention, a step is formed at the boundary between the steel sleeve portion 24 and the steel sleeve extension portion 32 so that the tip end side becomes thicker. Therefore, the function of the corrugated portion 25, that is, the shared load of the aluminum sleeve 23 is reduced by the detention portion 27.
Since this step has a function of transmitting to, there is no problem even if the structure with the corrugated part is omitted.

In the embodiment, the steel sleeve extension 32 has one step and the through hole 32a has the same inner diameter as a whole, but the steel sleeve extension has two steps, that is, the steel core aluminum stranded wire 3
It is also possible to form a stepped hole having two kinds of hole diameters, that is, an inner diameter portion covered on the outer periphery of the first layer of one aluminum wire portion 31b and an inner diameter portion covered on the outer periphery of the second layer. In this case, the second layer of the aluminum wire portion 31b of the steel-core aluminum stranded wire 31 is also stripped from the first layer. When a large-sized steel core aluminum stranded wire having a multi-layer aluminum wire portion is used, it is also possible to form a steel sleeve extension having a stepped hole with three or more steps.

[0016]

According to the present invention, the steel sleeve extension provided integrally with the steel clamp extends to a position beyond the central portion of the entire length of the compression type detention clamp, and the steel sleeve extension is made of aluminum. Since the structure is placed on the outer circumference of the wire inner layer and the outer diameter equivalent to the outer diameter of the wire can be secured, the strength of the compression type detention clamp against the maximum bending moment due to the vertical component force of the wire drawing tension when passing through the metal wheel is remarkably high. As a result, it is possible to prevent the compression type strain clamp from bending due to plastic deformation without the need for a clamp protector.

If the prefabricated overhead wire construction method is performed using the prefabricated electric wire of claim 2, it is not necessary to use a clamp protector, so that the efficiency of the work of extending the prefabricated electric wire is significantly improved.

[Brief description of drawings]

FIG. 1 is a front view of a compression type detention clamp according to an embodiment of the present invention.

FIG. 2 is a right side view of FIG.

3 (a) is a front view showing only the steel clamp in FIG. 1, and FIG. 3 (b) is a left side view thereof.

FIG. 4 (a) is a vertical cross-sectional view of an electric wire made of a steel core aluminum stranded wire to which the compression type strain clamp is compressed and fixed, and FIG. 4 (b) is a right side view.

FIG. 5 is a front view showing a state in which the compression-type detention clamp is passing over the rail wheel in the process of extending the prefabricated electric wire to which the compression-type detention clamp of the above-described structure is attached.

6A and 6B show another embodiment of the steel clamp in the compression type detention clamp of the present invention. FIG. 6A is a front view showing only the steel clamp, and FIG. 6B is a left side view thereof. .

FIG. 7 is a front view showing a conventional compression type detention clamp.

FIG. 8 is a right side view of FIG.

9 is a front view showing an aspect in which the compression type detention clamp is passing over the rail wheel in the process of extending the prefabricated electric wire to which the compression type detention clamp of FIG. 7 is attached.

FIG. 10 is a diagram for explaining the force that acts on the compression type strain clamp in the drawing process of FIG.

[Explanation of symbols]

 21 Compression Type Detention Clamp 22, 22A Steel Clamp 23 Aluminum Sleeve 24 Steel Sleeve 24a Hole 25 Corrugated 26 Adhesion 27 Drawover 27a Connection Hole 28 Aluminum Sleeve Body 29 Lug 31 Electric Wire (Steel Core Aluminum Stranded Wire) 31a Steel core 31b Aluminum wire part 31c Exposed inner layer part 32 Steel sleeve extension part 32a Through hole 33 Prefabricated electric wire L Compression type strain clamp total length M Central part of compression type strain clamp

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[Procedure amendment]

[Submission date] September 7, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 7

[Correction method] Change

[Correction content]

FIG. 7 is a front view showing a conventional compression type detention clamp.

Claims (2)

[Claims] 1. A steel clamp having at least a steel sleeve portion compressed and fixed on the outer circumference of a steel core of an electric wire end portion made of a steel core aluminum stranded wire, and a detention portion for holding the electric wire, and an aluminum wire of the electric wire. In a compression-type detention clamp comprising a wire portion and an aluminum sleeve that is compressed and fixed over the outer periphery of a portion of the steel clamp excluding the detention portion, the steel clamp has a tubular shape concentric with the steel sleeve portion. A steel sleeve extension that is fitted around the inner layer of any aluminum wire except the outermost layer of the aluminum wire is provided, and this steel sleeve extension extends at least to the position beyond the center of the entire length of the compression type detention clamp. A compression type detention clamp characterized by being 2. A prefabricated electric wire in which the compression type detention clamp according to claim 1 is compressed and fixed to both ends of an electric wire made of a steel core aluminum stranded wire, and the steel at the end of the electric wire made of a steel core aluminum stranded wire. When the core is exposed by cutting and removing the aluminum wire portion, the outermost layer of the aluminum wire portion is cut and removed further deeper than the cutting end position of the inner tank portion to form an exposed inner layer portion with an exposed outer periphery, With the steel sleeve extension of the compression type strain clamp clamped onto the outer circumference of this exposed inner layer, the steel sleeve is compressed and fixed to the steel core, and then the aluminum sleeve is placed on the steel sleeve and aluminum wire. A prefabricated electric wire characterized by being compressed and fixed over.