JP2938265B2 - Sleeve for connecting sector-shaped conductor and method for connecting sector-shaped conductor using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductor having a fan-shaped cross section, that is, a connecting sleeve for connecting power cables using the fan-shaped conductor, and connecting the fan-shaped conductors using the connecting sleeve. How to do it.

[0002]

2. Description of the Related Art Recently, as a rubber / plastic power cable such as a crosslinked polyethylene power cable (CV cable), mainly for the purpose of downsizing,
As a high-voltage cable of the 66 kV class, a cable using a sector-shaped conductor having a sector-shaped cross section is being put to practical use. FIG. 11 shows an example of a three-core CV cable using such a fan-shaped conductor.

In FIG. 11, three fan-shaped conductors 1 are each formed by twisting a plurality of good conductive wires such as copper wires and forming a fan-shaped cross section. Each of the sector-shaped conductors 1 has an inner semiconductive layer 2, an insulator layer 3, an outer semiconductive layer 4, and a shielding layer 5 provided on the outer periphery in that order from the inner side, and these three conductors are circular as a whole. And an anticorrosion layer 6 is provided on the entire outer periphery thereof.

Conventionally, cables using fan-shaped conductors have been used exclusively for low-voltage applications of 22 kV to 33 kV or less. For such low-voltage cables, soldered sleeves are generally used to connect conductors. Was used. On the other hand, in a high-voltage cable of 66 kV class or higher using a normal circular conductor, a sleeve compression connection method has conventionally been adopted for conductor connection. Unlike the connection method using a soldered sleeve, this sleeve compression connection method does not use a fire unlike the connection method using a soldered sleeve, and there is no difference in the other performance points from the connection method using a soldered sleeve. In order to put the used cable into practical use in the 66 kV class or more, it is considered to apply the sleeve compression connection method.

In the sleeve compression connection method, generally, conductors are exposed by removing an insulating layer or the like at the end of each cable, and the exposed end of each conductor is inserted into the connection sleeve from both sides thereof, and then the sleeve is compressed. In applying such a sleeve compression connection method to the connection of the sector-shaped conductor as described above, a connection sleeve 20 as shown in FIGS. 12 and 13 is generally used. It is thought that. This connection sleeve 20
The conductor insertion holes 10, 1 are formed in a cylindrical shape so as to have substantially the same outer diameter as a whole except for the tapered portions 20A at both ends, and have fan-shaped cross sections along the axial direction from both ends.
1 is formed.

[0006]

When connecting the sector-shaped conductors by the sleeve compression connection method using the connection sleeve as described above, there are the following problems.

That is, in order to sufficiently increase the connection strength, that is, the limit strength at which the connection portion can withstand the tensile force on the conductor in connecting the conductors using the connection sleeve, a conductor insertion hole is required. It is necessary to increase the contact area between the conductor surface and the inner surface of the conductor insertion hole by increasing the length, but in this case, the length of the connection sleeve also inevitably increases, and the material cost and processing cost of the connection sleeve increase. In addition, a problem arises in the operation of compressing the sleeve after inserting the conductor end into the conductor insertion hole. Therefore, it has been desired to develop a method that can increase the connection strength without increasing the length of the connection sleeve.

The present invention has been made in view of the above circumstances, and when connecting fan-shaped conductors by the sleeve compression connection method, a sufficiently high connection strength can be obtained without increasing the length of the connection sleeve. It is an object of the present invention to provide a sleeve for connecting a sector-shaped conductor and a method for connecting a sector-shaped conductor using the sleeve.

[0009]

In order to solve the above-mentioned problems, according to the present invention, the shape of the connecting sleeve, particularly the outer peripheral surface thereof, is formed in a shape which has not been considered conventionally. .

That is, in the fan-shaped conductor connecting sleeve according to the first aspect of the present invention, a conductor insertion hole having a fan-shaped cross section is formed along the axial direction from both ends, and the outer peripheral surface of the central portion in the axial direction has a small diameter. It is characterized in that it is a cylindrical surface, and the outer peripheral surfaces of both end portions adjacent to the central portion are large-diameter cylindrical surfaces.

Further, the inventions of claims 2 and 3 relate to a method of connecting fan-shaped conductors using the above-mentioned sleeve.

More specifically, according to the second aspect of the invention, when connecting the ends of the sectoral conductors having a sectoral cross section, the conductor insertion holes of the connection sleeve having the conductor insertion holes formed from both ends are connected. In the method of connecting a fan-shaped conductor by connecting the fan-shaped conductor by inserting the end of the fan-shaped conductor and compressing the sleeve from the outer peripheral side, the cross section of the conductor insertion hole has a fan-shaped shape as the connection sleeve. A sleeve is prepared in which the outer peripheral surface of a central portion in the axial direction is a small-diameter cylindrical surface and the outer peripheral surfaces of both end portions adjacent to the central portion are a large-diameter cylindrical surface, and the end of the sector-shaped conductor is After being inserted into the insertion hole, the large-diameter cylindrical surface at both end portions of the connection sleeve is compressed from the outer peripheral side until the diameter becomes the same as the outer diameter of the small-diameter cylindrical surface at the central portion. is there.

According to a third aspect of the present invention, in connecting the ends of the sector-shaped conductor having a sector-shaped cross section, the sector-shaped conductor is inserted into the conductor insertion hole of the connection sleeve in which the conductor insertion holes are formed from both ends. In the method of connecting a fan-shaped conductor by connecting the fan-shaped conductor by inserting the end portion and compressing the sleeve from the outer peripheral side, the connecting sleeve has a fan-shaped cross-section of the conductor insertion hole, and has an axial direction. Prepare a sleeve in which the outer peripheral surface of the central portion is a small-diameter cylindrical surface and the outer peripheral surfaces of both end portions adjacent to the central portion are a large-diameter cylindrical surface, and insert the end of the fan-shaped conductor into the conductor insertion hole. After that, the small-diameter cylindrical surface at the center of the connecting sleeve is compressed from the outer peripheral side until the diameter becomes a predetermined finished diameter, and then the large-diameter cylindrical surfaces at both ends of the connecting sleeve are compressed.
It is characterized in that it is compressed from the outer peripheral surface side until its diameter becomes the same as the finished diameter of the central part.

[0014]

According to the first aspect of the present invention, there is provided a fan-shaped conductor connecting sleeve.
The central part in the axial direction and the parts on both sides (both ends)
The outer diameter of the central portion is a small-diameter cylindrical surface having a relatively small diameter, and the outer peripheral surfaces of both end portions are a large-diameter cylindrical surface having a relatively large diameter. When connecting the sector-shaped conductors using such a connection sleeve, insert the end of the sector-shaped conductor to be connected into a conductor insertion hole having a sector-shaped cross section of the connection sleeve, and then use a round die or a hexagonal die. Then, the connection sleeve is compressed from the outer peripheral surface side, and the inner surface of the conductor insertion hole and the outer surface of the fan-shaped conductor are pressed. By the way, in connection of conductors in a general power cable, it is desired that the outer diameter of the sleeve after conductor connection is substantially uniform over the entire length from the viewpoint of winding an insulating tape around the outer periphery of the connection sleeve. Therefore, even when the connecting sleeves having different outer diameters at the central portion and the both end portions as described above are used, during compression for crimping between the connecting sleeve and the fan-shaped conductor, the entire length of the connecting sleeve is substantially reduced. It is desired to deform so as to have the same diameter. In the case of compressive deformation to have the same diameter after compression in this way, there is a difference in the amount of deformation between both ends, which were initially large in diameter, and the central portion, which was small in diameter. There is also a difference in the amount of deformation. Therefore, the cross-sectional dimensions and cross-sectional shape of the fan-shaped conductor after compression are different between the center portion and both end portions of the connection sleeve, and such a difference causes a mechanical anchor effect, which is high with respect to the force in the conductor pulling direction. It will show the connection strength.

The operation of the above-described compression will be described in detail with reference to the method according to the second aspect of the present invention. In the method according to the second aspect of the present invention, after inserting the end portion of the sector-shaped conductor into the conductor insertion hole, only the end portion, that is, the portion having the large-diameter cylindrical surface, of the entire connection sleeve is moved to the central portion. That is, it is compressed until it becomes equal to the outer diameter of the small-diameter cylindrical surface. By doing so, only the ends of the connection sleeve are reduced in diameter, and the inner surface of the conductor insertion hole is crimped to the internal fan-shaped conductor at that portion, and the fan-shaped conductor located inside the both ends is formed. It is compressed and deformed. At this time, inside the both ends of the connecting sleeve (the portion of the large-diameter cylindrical surface), the fan-shaped conductor is not only reduced in diameter but also does not deform uniformly because it originally has a fan-shaped irregular cross section. , Is compressed and deformed anisotropically to have a cross-sectional shape different from the original sector (usually a shape closer to a circle than the sector before compression). On the other hand, the central portion (portion of the small-diameter cylindrical surface) of the connection sleeve is not compressed, so that the inner sector-shaped conductor is not deformed and the original diameter and the original sector shape are maintained. Therefore, of the portions of the sectoral conductor inserted into the conductor insertion holes of the connection sleeve, the portions located inside the both ends of the large diameter of the sleeve are compared with the portions located inside the central portion of the small diameter of the sleeve. And the cross-sectional shape is also different. Therefore, when a tensile force is applied to the fan-shaped conductor, the boundary between the portion corresponding to the central portion of the sleeve and the portion corresponding to both ends of the sleeve as described above has a cross-sectional dimension and a cross-sectional shape between them. The difference acts as an anchor, preventing the sector conductor from slipping out of the sleeve. Therefore, a large connection strength is exhibited with respect to the force in the tensile direction.

In the method according to the third aspect of the present invention, after the fan-shaped conductor is inserted, the central portion of the connecting sleeve, that is, the portion having the small-diameter cylindrical surface is first compressed to some extent (until a predetermined finished diameter is reached), and then the connecting sleeve is compressed. Both ends of the sleeve, that is, a portion having a large-diameter cylindrical surface, are compressed until the diameter becomes the same as the finished diameter at the center. In the case of this method, the central portion of the connecting sleeve is also compressed and deformed, but since the initial diameter of the central portion is smaller than that of both ends, the degree of compression of the central portion is smaller than that of both ends. Accordingly, the degree of deformation of the fan-shaped conductor located inside the small-diameter central portion among the portions of the fan-shaped conductor inserted into the conductor insertion holes of the connection sleeve is also located inside the large-diameter end portions. It becomes smaller than the part. That is, as in the case of the method according to the second aspect of the present invention, of the respective portions of the fan-shaped conductor, the portions located inside the large-diameter end portions of the connection sleeve are replaced with the small-diameter central portion of the connection sleeve. It has a smaller diameter than the portion located inside and has a different cross-sectional shape. Therefore, the anchor effect similar to the above prevents the fan-shaped conductor from slipping out of the sleeve, and exhibits a large connection strength against a force in the pulling direction. In the method according to the third aspect of the present invention, the inner surface of the conductor insertion hole and the outer surface of the fan-shaped conductor are crimped not only at both ends but also at the center of the connection sleeve. And the connection strength is further increased.

[0017]

1 to 3 show an example of a connecting sleeve according to the first aspect of the present invention.

1 to 3, a connecting sleeve 20 is used.
Is basically made of a good conductive material of the same material as the sector conductor to be connected. When the sector conductor is made of copper, the connection sleeve 20 is also made of copper, and the sector conductor is made of aluminum. In such a case, an aluminum alloy is also used for the connection sleeve 20. The connection sleeve 20 is formed so that a conductor insertion hole 21 having a fan-shaped cross section is formed through the connection sleeve 20 along the axial direction, and has a hollow cylindrical shape as a whole.
Further, of the total length of the connection sleeve 20, the length L ₁
Of the central portion 22, the outer peripheral surface thereof is a smaller diameter cylindrical surface 22A of the diameter of _{R 1,} part of its length _L 2 adjacent to either side of the central portion 22, _{L 3} (end portions) 23 and 24, respectively The outer peripheral surface is a large-diameter cylindrical surface 23A of R ₂ (> R ₁ ).

When connecting the sector-shaped conductors using such a connecting sleeve 20, first, the two conductors to be connected must be connected.
Each end 1A of the fan-shaped conductor 1 is inserted into the conductor insertion hole 21 of the connection sleeve 20 from both sides thereof. And Claim 2
In the method of the invention, only the large-diameter cylindrical surfaces 23A and 24A of both end portions 23 and 24 are compressed from the outer peripheral surface side by a round die or a hexagonal die. Compression of the end portions 23 and 24 is performed until the outer diameter also becomes the diameter _{R 1} of the small diameter cylindrical surface 22A of the central portion 22. The state after the compression molding is performed only on both end portions 23 and 24 in this manner is shown in FIGS.
As shown in FIG.

As shown in FIG. 5, since the fan-shaped conductor 1 is not compressed in the central portion 22, the cross-sectional shape and the cross-sectional dimensions are the same as those in the initial state (see FIG. 2). On the other hand, at both end portions 23 and 24, the fan-shaped conductor 1 is compressed as shown in FIG. 6, and its sectional dimensions and shape are different from the original dimensions and shape before compression. Specifically, the maximum diameter of the cross section of the sector-shaped conductor 1 is reduced, and the cross-sectional shape is closer to a circle than the original sector. Therefore, in the state after the connection sleeve 20 is compressed, the sectional size and sectional shape of the sector-shaped conductor 1 inside the central portion 22 of the sleeve and the end portions 23 and 24 are different. In this case, the portion located at the central portion 22 is larger than the portions located at both end portions 23 and 24. Therefore, near the boundary between the two, there is a step on the surface of the fan-shaped conductor 1 (the surface that is in contact with the inner surface of the conductor insertion hole 21 of the connection sleeve 20), and that portion is mechanically resistant to the force in the conductor pulling direction. The fan-shaped conductor 1 functions as a simple anchor and can be effectively prevented from coming off. Therefore, a high connection strength is exhibited with respect to the force in the conductor pulling direction.

On the other hand, FIG. 7 shows an example of the method according to the third aspect of the present invention in a stepwise manner. In this case, the connection sleeve 2
After inserting the end portions 1A of the two conductors 1 to be connected from both sides into the conductor insertion holes 21 of the
The small-diameter cylindrical surface 22A of the outer diameter R ₁ of the central portion 22 is compressed from the outer peripheral surface side by the cylindrical die, etc., to the diameter to a predetermined finish diameter R _3. Then, the outer diameter R of both end portions 23 and 24
₂ of the large diameter cylindrical surface 23A, 24A is compressed from the outer peripheral surface side by a likewise cylindrical die, etc., the central portion 22 of a diameter of above
The finished diameter R ₃ after compression with the same diameter.

FIGS. 8 and 9 show the state after compression of the central portion 22 and both end portions 23 and 24 of the connecting sleeve 20 in this case.
Shown in In the central part 22 of the connecting sleeve 20, FIG.
As shown in (1), the sectional shape of the internal sector-shaped conductor 1 is slightly deformed from the initial sector before compression, and the maximum diameter thereof is also slightly reduced. On the other hand, at both end portions 23 and 24 of the connection sleeve 20, as shown in FIG. 9, the cross-sectional shape of the internal sector-shaped conductor 1 is largely deformed from the initial sector-shaped before compression to a shape close to a circle. The diameter is also considerably smaller. Therefore, the central portion 22 and both end portions 23, 24 of the connection sleeve 20 are divided into the fan-shaped conductors 1 therein.
Are different from each other in the cross-sectional shape and the maximum diameter, and the sector effect conductor 1 is prevented from falling out of the connection sleeve 20 by the anchor effect as in the example described above, and a high connection strength in the tensile direction is exhibited.

In each of the embodiments described above, the connection sleeve 20 has a conductor insertion hole 21 penetrating from one end to the other end thereof, but as shown in FIG. The hole may be separated by a partition wall 30 in the middle, and the conductor insertion hole 21A at one end and the conductor insertion hole 21B at the other end may be separated. In this case, however, the length L ₁ of the central portion 22 having a smaller diameter cylindrical surface 22A, it is necessary to sufficiently longer than the thickness T of the partition wall 30.

[0024]

According to the connecting sleeve of the first aspect of the present invention, the central portion of the connecting sleeve in which a conductor insertion hole having a linear cross section for inserting two fan-shaped conductors to be connected from both sides is formed. The outer peripheral surface of is a small-diameter cylindrical surface, while the outer peripheral surfaces of both ends of the connection sleeve are large-diameter cylindrical surfaces, and there is a difference in outer diameter between the two. After that, if the connection sleeve is compressed from the outer peripheral surface side so that the outer diameters of the center portion and both end portions become equal, the center portion of the connection sleeve among the portions of the fan-shaped conductor inserted in the connection sleeve There is a difference in the cross-sectional shape and cross-sectional dimension between the portion located inside the inside of the connecting sleeve and the portion located inside the both ends of the connecting sleeve, so that the sector is formed by the anchor effect at the boundary between them. The conductor is It is reliably and effectively prevented from escaping from over blanking can exhibit high connection strength against tensile force. And since such a high connection strength is obtained, it is not necessary to particularly lengthen the entire length of the connection sleeve, and therefore, the size of the connection sleeve is reduced by shortening the connection sleeve, and the material cost and the processing cost of the connection sleeve are reduced as compared with the conventional case. Can also be reduced.

According to the sleeve connecting method according to the second and third aspects of the present invention, when the fan-shaped conductors are actually connected to each other using the connecting sleeve as described above, the length of the sleeve is particularly increased. Therefore, the fan-shaped conductors can be connected to each other with high connection strength.

[Brief description of the drawings]

FIG. 1 is a partially longitudinal side view showing an example of a connection sleeve according to the first aspect of the present invention.

FIG. 2 is a cross-sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB or CC in FIG. 1;

FIG. 4 is a vertical sectional side view showing an example of a state after the connection sleeve is compressed in the sleeve connection method according to the second embodiment of the present invention.

FIG. 5 is a sectional view taken along line DD of FIG. 4;

FIG. 6 is a sectional view taken along line EE or line FF in FIG. 4;

FIG. 7 is a schematic view showing stepwise an example of the sleeve connecting method of the invention of claim 3;

8 is a sectional view taken along line GG of FIG.

9 is a sectional view taken along line HH or II in FIG. 7;

FIG. 10 is a partial vertical sectional side view showing another example of the connection sleeve of the invention of claim 1;

FIG. 11 is a cross-sectional view showing a typical example of a three-core CV cable using a fan-shaped conductor.

FIG. 12 is a partially longitudinal side view showing a connection sleeve which is conventionally considered to be used for connecting fan-shaped conductors by a sleeve compression connection method.

13 is a sectional view taken along line JJ or line KK in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fan-shaped conductor 1A End part 20 Connection sleeve 21, 21A, 21B Conductor insertion hole 22 Central part 22A Small diameter cylindrical surface 23, 24 Both end parts 23A, 24A Large diameter cylindrical surface

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shotaro Yoshida 1-5-1 Kiba, Koto-ku, Tokyo Fujikura Electric Wire Co., Ltd. (72) Inventor Masayuki Tan 1-1-5-1 Kiba, Koto-ku, Tokyo Fujikura Electric Wire Incorporated (72) Inventor Akinori Watanabe 1-5-1, Kiba, Koto-ku, Tokyo Fujikura Electric Wire Co., Ltd. (56) References Japanese Utility Model Sho-60-18990 (JP, U) Japanese Utility Model Sho 52-127279 (JP) , U) Jikken 48-29985 (JP, Y1) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01R 3/00-4/22

Claims (3)

(57) [Claims] 1. A conductor insertion hole having a fan-shaped cross section along the axial direction from both ends is formed, and an outer peripheral surface at a central portion in the axial direction is a small-diameter cylindrical surface, and both end portions adjacent to the central portion are formed. A fan-shaped conductor connection sleeve, characterized in that the outer peripheral surface is a large-diameter cylindrical surface. 2. When connecting the ends of a sector-shaped conductor having a sector-shaped cross section, the ends of the sector-shaped conductor are inserted into the conductor insertion holes of the connection sleeve in which the conductor insertion holes are formed from both ends. In the method for connecting a sector-shaped conductor by connecting the sector-shaped conductor by compressing the sleeve from the outer peripheral side, the connecting sleeve has a conductor insertion hole having a sector-shaped cross-section, and an outer peripheral surface at a central portion in the axial direction. A sleeve having a small-diameter cylindrical surface and a large-diameter cylindrical surface at both ends adjacent to the center thereof is prepared, and after inserting the end of the fan-shaped conductor into the conductor insertion hole, a connection sleeve is formed. Wherein the large-diameter cylindrical surface at both end portions is compressed from the outer peripheral side until the diameter becomes the same as the outer diameter of the small-diameter cylindrical surface at the central portion. 3. When connecting the ends of a sector-shaped conductor having a sector-shaped cross section, the ends of the sector-shaped conductor are inserted into the conductor insertion holes of the connection sleeve in which the conductor insertion holes are formed from both ends. In the method for connecting a sector-shaped conductor by connecting the sector-shaped conductor by compressing the sleeve from the outer peripheral side, the connecting sleeve has a conductor insertion hole having a sector-shaped cross-section, and an outer peripheral surface at a central portion in the axial direction. A sleeve having a small-diameter cylindrical surface and a large-diameter cylindrical surface at both ends adjacent to the center thereof is prepared, and after inserting the end of the fan-shaped conductor into the conductor insertion hole, a connection sleeve is formed. The central portion of the small-diameter cylindrical surface is compressed from the outer peripheral side until its diameter becomes a predetermined finished diameter, and then the large-diameter cylindrical surface at both ends of the connecting sleeve is the same diameter as the finished diameter of the central portion. Sleeve connection sector conductors, which comprises compressing from the outer peripheral surface side until.