JP5101536B2 - Reduced pooling eye - Google Patents

Description

  The present invention relates to a reduced pooling eye used as a cable pulling terminal when laying a cable, for example, in an underground conduit or a cave, and in particular, to improve the waterproofness of the cable and reduce the outer diameter. This relates to the reduced pooling eye.

  Conventionally, for example, when laying a power cable in an underground conduit or the like, a traction wire or the like is laid in advance in the underground conduit, and a pooling eye is attached to the end of the power cable, and the pulling eye is attached to the pooling eye. By attaching and pulling a wire or the like, the work of drawing the power cable into the underground conduit or the like is performed. Waterproofing is required so that moisture, moisture, and the like do not enter and permeate from the attachment portion between the pooling eye and the power cable used for such cable drawing work. Further, when the inner diameter of an underground conduit for laying a power cable is narrow (small), it is desired to reduce the outer diameter of the entire pooling eye as much as possible.

  When waterproofing between the pooling eye and the power cable, first, leave the cable sheath from the end of the power cable and process the cable insulator into a tapered shape to form the penciling part, then the remaining cable The end of the cable conductor exposed from the sheath is compression-fastened to the compression portion in the pooling eye main body. Next, the end of the remaining cable sheath is warmed and stretched to cover the short end (skirt portion) of the main body of the pooling eye, and the stretched cable sheath end is fastened and fixed by a wire grip or the like. Furthermore, a waterproof part is formed by wrapping tape and sealing tape around both the short end (skirt part) and compression part of the pooling eye body, and waterproofing is applied between the end of the pooling eye and the cable sheath. The The prior art for performing this waterproofing process is described in, for example, the section of the prior art in Patent Document 1. The short end (skirt part) of the pooling eye body has a function of a drawing allowance for gently narrowing along with or extending the cable sheath end together with the cable insulating penciling part. Yes.

  However, the conventional pooling eye has a structure for waterproofing by extending the end of the cable sheath in order to reduce the outer diameter of the entire pooling eye. There is a problem that the copper tape for shielding underneath is displaced, which may lead to a decrease in waterproof performance. In addition, the cable insulation is provided with a penciling part in order to combine reduction and waterproofing performance, but because of this penciling part structure, it cannot be reduced, and the cable sheath terminal has a long waterproofing performance. There is a problem that the pooling eye main body cannot be formed thick at the short end (skirt portion) so that it can be maintained.

  In order to solve the above-mentioned problems, there is one in which waterproofing treatment with a waterproof compound is performed between the pooling eye and the end of the cable sheath (for example, see Patent Document 1). In the conventional pooling eye described in Patent Document 1, the cable sheath is removed from the power cable terminal without leaving the cable sheath and forming the penciling portion on the cable insulator, and then the remaining cable sheath The end of the cable conductor exposed from is compressed and fastened to the compression part in the pooling eye main body without the skirt part. Next, a space is provided between the remaining end of the cable sheath and the cable conductor, specifically, in the space formed by the compression portion, the cable conductor, the hook fishing bracket, the end of the cable sheath, the cable insulator, etc. By filling and curing a liquid waterproof compound, the waterproof property is secured between the pooling eye and the power cable.

JP-A-9-275625

However, the conventional pooling eye described in Patent Document 1 has the following problems.
(1) The waterproofing treatment in which a liquid waterproofing compound is poured into the space between the end of the cable sheath and the cable conductor to cure it takes time from the melted state to the cured state, resulting in poor production efficiency. It is not suitable for the manufacturing process.
(2) Since the liquid waterproof compound is poured into the space between the end of the cable sheath and the cable conductor and cured, it is impossible to check and observe the filled and cured state of the waterproof compound in the space. Check whether the waterproof compound is tightly sealed and tightly sealed at the interface between the cable sheath end and the waterproof compound, or between the compression part (sleeve) of the pooling eye body and the waterproof compound. May be difficult and may not have sufficient waterproof performance.
(3) A pooling eye using a liquid waterproof compound may not be able to meet the requirements for attaching to one or both ends of the cable at the start or end of cable production quickly without reducing the production speed in the pooling eye installation work. .
(4) Moreover, in the pooling eye described in the prior art of Patent Document 1, a cable insulating member is provided with a penciling portion in order to combine reduction and waterproof performance, and there is this penciling portion structure. Therefore, the terminal of the cable sheath cannot be formed thickly at the short end (skirt portion) of the pooling eye main body, and there is a problem in downsizing and waterproof performance.

  Accordingly, an object of the present invention is to provide a reduced pooling eye that improves waterproof performance and realizes reduction without causing breakage, damage or the like of the cable sheath.

In order to achieve the above object, the present invention provides a cylindrical compression that compresses and clamps the end of the cable conductor that is exposed by removing the cable insulator from the cable end portion without removing the cable insulator into a tapered shape. And a rod-shaped rod portion formed at one end of the compression portion, and a cylindrical skirt portion having a length extending toward the cable longitudinal direction at the other end of the compression portion and longer than the compression portion. An eye body, and at least the skirt portion is configured by a waterproof portion subjected to waterproof treatment while a portion of the cable sheath of the cable terminal portion remaining on the outer periphery of the skirt portion is narrowed down. A reduced pooling eye characterized by the above is provided.
In the reduced pooling eye, the waterproof part is preferably made of a waterproof tape or a shrinkable tube, and the outer diameter of the skirt part may be formed with an arbitrary dimension relative to the outer diameter of the compression part.

  ADVANTAGE OF THE INVENTION According to this invention, the pooling eye which improved waterproof performance and implement | achieved size reduction can be provided, without causing the failure | damage of a cable sheath, damage, etc.

(A) is the fragmentary sectional view which shows schematically one structural example of the reduction | restoration pooling eye which is 1st Embodiment based on this invention, (b) is the pulling side of the reduction | restoration pooling eye shown to (a). FIG. (A) is a partial sectional view schematically showing a pooling eye main body, (b) is a view seen from the pooling eye main body base side shown in (a), and (c) is a view seen from the pooling eye main body skirt side. It is. (A) is a partial sectional view schematically showing a pooling eye body according to a second embodiment, (b) is a view seen from the base side of the pooling eye body shown in (a), and (c) is a pooling It is the figure seen from the eye main body skirt part side. (A) is a partial sectional view schematically showing a pooling eye main body according to a third embodiment, (b) is a view seen from the base side of the pooling eye main body shown in (a), and (c) is a pooling It is the figure seen from the eye main body skirt part side.

  Hereinafter, a preferred first embodiment of the present invention will be specifically described with reference to the accompanying drawings.

(Configuration of reduced pooling eye)
1A and 1B show a reduced pooling eye. In FIG. 1A, reference numeral 10 denotes a reduced pooling eye used as a cable traction terminal when laying a power cable on an underground conduit or the like, and reference numeral 40 denotes a power cable. The basic configuration of the reduced pooling eye 10 is that the pulling member 20 that pulls the power cable 40 and the cable conductor 41 of the power cable 40 are compressed or fastened to the compression unit 13 by crushing or caulking, and the compression unit 13 and the compression unit 13 are further compressed. A pooling eye main body 11 having a waterproof portion 26 that has been subjected to waterproofing processing by narrowing the end of the cable sheath 43 on the outer periphery of the skirt portion 14 at the other end of the cable, and a branching member that fixes the pooling eye main body 11 to the pulling member 20 It is mainly comprised by three members with 30. The pooling eye main body 11, the pulling member 20, and the branching member 30 are formed in a circular shape, but are not particularly limited to the shapes, and may be rectangular or conical. In addition, the material may be any material that has sufficient mechanical strength to pull the power cable 40. For example, metal materials such as iron, aluminum, copper, and alloys thereof are suitable.

(Configuration of power cable)
The power cables 40 are used as a set of three. In FIG. 1A, two of the three power cables 40 are omitted. Examples of the power cable 40 include a crosslinked polyethylene insulated vinyl sheath cable (CV cable). In the power cable 40, for example, a cable conductor 41, a cable insulator 42, a cable external semiconductive layer (not shown), a cable shielding copper tape layer, a wire shield, and a cable sheath 43 are sequentially formed.

(Configuration of traction member)
As shown in FIGS. 1A and 1B, the pulling member 20 for pulling the power cable integrally includes a metal fitting body (fishing fitting) 21 and a flange (fisher) portion 22. The material of the pulling member 20 is made of a metal material such as iron (SS400, SF45), for example. The metal fitting body 21 includes a cylindrical body 21b having a hemispherical head portion 21a at one end in the longitudinal direction and an open end at the other end. A flange portion 22 projects from the hemispherical head portion 21 a of the metal fitting body 21. The flange portion 22 is made of a flat block body having a planar shape surrounded by a semicircumference and a tangent line in contact with the semicircumference. The block body is formed with an insertion hole 22a penetrating circularly, and a pulling wire or a pulling rope (not shown) is attached thereto.

  As shown in FIG. 1 (a), a step-shaped storage space 23 having a stepped step 20a facing the opening is provided inside a metal fitting body (fishing fitting) 21 having one end formed in a cylindrical shape with a bottom. Is formed. The storage space 23 includes a small-diameter accommodating portion 23a in which the disk-shaped branch member 30 is accommodated, and a large-diameter accommodating portion 23b having an inner diameter larger than the inner diameter of the small-diameter accommodating portion 23a. On the inner peripheral surface of the small-diameter accommodating portion 23a, an inner screw 23c that is screwed with an outer screw 31 provided on the outer peripheral surface of the branch member 30 is formed. A screw mounting hole 23d through which a screw (not shown) is screwed is formed through a portion corresponding to the internal screw 23c of the small diameter accommodating portion 23a. The branch member 30 is firmly attached in the small diameter accommodating portion 23a of the metal fitting body (fishing fitting) 21 by screwing a set screw (not shown) into the screw attachment hole 23d.

(Configuration of the pooling eye body)
Referring to FIGS. 2A to 2C, the pooling eye main body 11 shown in FIG. 1A is shown. In these drawings, the pooling eye main body 11 includes a cylindrical rod portion 12, a cylindrical compression portion 13 having an outer diameter larger than the outer diameter of the rod portion 12, and a compression portion 13 having the rod portion 12 at one end. And a cylindrical skirt portion 14 having a longer length than the compression portion 13 at the other end. The material of the pooling eye main body 11 is made of a metal material such as iron (S10C, S15C, S15CK), aluminum, copper, or an alloy thereof. The rod portion 12 and the compression portion 13 are formed to be connected via a step 15. An external screw 12 a is formed at the tip of the rod portion 12. A split pin hole 12b is formed through the external screw 12a of the rod portion 12. The pooling eye main body 11 is fastened and fixed to the branch member 30 by screwing the tightening nut 17 to the external screw 12a of the rod portion 12 via the washer 16. The pooling eye main body 11 is formed integrally with the pulling member 20 via the branch member 30.

  In the compression part 13 of the pooling eye main body 11, the terminal of the cable conductor 41 exposed from the cable sheath 43 of the power cable 40 is compression-fastened as shown in FIG. The end of the cable conductor 41 is fixed in a compressed state by, for example, compressing the compression portion 13 radially inward. In addition to the function of compressing and fastening the end of the cable conductor 41, the compression unit 13 also has a function of pulling the power cable 40 against the tension generated when the power cable 40 is pulled into the pipe line by, for example, a pulling wire. Yes. The outer diameter of the compression portion 13 may be the same as that of the skirt portion 14 or may be smaller than that of the skirt portion 14.

  As shown in FIG. 1A, the cable conductor 41 and the thin skin portion 44 of the cable insulator 42 are inserted into the skirt portion 14 of the pooling eye main body 11. The cable insulator 42 is partially removed so as not to reach the cable conductor 41, thereby leaving a thin skin portion 44 of the cable insulator 42. Note that the cable conductor 41 may be completely deleted so as to reach the cable conductor 41 as long as the cable conductor 41 is not scratched or damaged.

  As shown in FIGS. 2A to 2C, the skirt portion 14 is set smaller than the cross-sectional thickness of the compression portion 13 and has an inner diameter larger than the inner diameter of the compression portion 13. The compression portion 13 and the skirt portion 14 are formed by connecting the expanded inner peripheral surface and the reduced outer peripheral surface via tapered inclined steps 18 and 18 that are alternately inclined, and the outer diameter of the skirt portion 14 is It is set smaller than the compression unit 13. The outer diameter of the skirt portion 14 may be the same as or larger than that of the compression portion 13 as in the second and third embodiments described later. Can be set. The skirt portion 14 is set longer than the length of the compression portion 13 and extends in the cable longitudinal direction.

  After the cable conductor 41 and the thin skin portion 44 of the cable insulator 42 are inserted into the skirt portion 14, the end of the cable sheath 43 is squeezed on the outer periphery to perform waterproofing between the skirt portion 14 and the cable sheath 43. It is important to form the waterproof part 26. According to FIG. 1A, a heating process for heating and softening the end of the cable sheath 43 that has been narrowed down on the skirt portion 14 and a winding process for winding a bind wire 24 such as an iron wire on the end of the cable sheath 43 are performed. . Further, the waterproof portion is formed by performing a waterproofing process across the bind line 24, the outer periphery of the compression portion 13 and the skirt portion 14, and the main body side terminal portion of the skirt portion 14 and the cable sheath 43. By this waterproofing treatment, the cable conductor 41 is hermetically and liquid-tightly closed in the pooling eye main body 11 so as not to be exposed to moisture, moisture, etc., and waterproofing between the skirt portion 14 and the cable sheath 43 is ensured.

  A method of attaching the power cable 40 to the pooling eye main body 11 is as follows. First, the cable shield copper tape layer (not shown), the wire shield, or the cable outer semiconductive layer is peeled off so as to leave the cable sheath 43 from the power cable terminal portion, and the thin skin portion 44 is left at the tip portion and processed into a taper shape. The cable insulator 42 is removed (cut off) at right angles to the axial (diameter) direction so as not to be molded (penciling portion). Thereafter, the terminal of the remaining cable sheath 43 is left folded, the cable conductor 41 is exposed, and the terminal of the cable conductor 41 is inserted into the compression portion 13 of the pooling eye main body 11. Subsequently, the cable conductor 41 portion having the thin skin portion 44 of the cable insulator 42 is inserted into the skirt portion 14. After insertion, the compression portion 13 is crushed to compress the cable conductor 41. Next, the end of the folded cable sheath 43 is returned to the original position, narrowed down along the outer periphery of the skirt portion 14, and the end portion and the portion close to the main body side of the cable sheath 43 are wound and fixed by the bind wire 24. Thus, the end of the cable sheath 43 is inserted on the outer periphery of the skirt portion 14. The end of the cable sheath 43 is performed while being heated and softened so as to be easily narrowed down to the skirt portion 14. Next, the waterproof tape 25 is wound around the binding wire 24, the outer periphery of the compression portion 13 and the skirt portion 14, and the main body side end portion of the skirt portion 14 and the cable sheath 43. In this way, the outer diameter of the pulling member 20 of the reduced pooling eye 10 is reduced to the same diameter as or smaller than the three cable outer diameters by narrowing the end of the cable sheath 43 onto the skirt portion 14 and closely contacting it. The In this embodiment, the bind wire winding process is performed. However, it may not be performed if the waterproof member such as the waterproof tape and the shrinkable tube has sufficient adhesion.

  The length of the skirt portion 14 of the pooling eye main body 11 is about 20 mm to 30 mm as a squeezing margin after the cable sheath is stretched in the conventional pooling eye main body that stretches the cable sheath and performs waterproofing. In addition, the cable insulating portion differs depending on the cable size and voltage (the outer diameter of each component of the power cable varies depending on the thickness of the insulator), and thus approximately 20 mm to 50 mm is required. In contrast, the length of the skirt portion 14 of the pooling eye main body 11 according to this embodiment is preferably set to about 40 mm or more. If the length of the skirt portion 14 is ensured, sufficient waterproof performance can be obtained. In addition, since no penciling portion is formed in the cable insulator, the pooling eye can be reduced.

  As the waterproof tape 25, for example, an adhesive polyethylene tape or a self-bonding tape is suitable. Of course, instead of the waterproof tape 25, for example, a heat shrinkable tube or a normal temperature shrinkable tube may be used as the waterproof member. Instead of the binding wire 24 such as an iron wire, for example, a rubber tube may be used with the function of the binding member. When the end of the cable sheath 43 is narrowed down on the skirt portion 14 and is formed by wrapping a rubber tube thereon, a waterproof effect between the skirt portion 14 and the end of the cable sheath 43 can be obtained. In order to heat and soften the end of the cable sheath 43, for example, a gas burner or a heating device such as an electric heater is used.

(Configuration of branch member)
The branch member 30 fixed in the metal fitting body 21 of the pulling member 20 is formed of a disk-shaped block body as shown in FIG. The material of the branch member 30 is made of the same metal material (SS400, SF45) as that of the pulling member 20. On the outer peripheral surface of the branch member 30, an external screw 31 is formed that is screwed and fastened to the internal screw 23 c of the small-diameter accommodating portion 23 a of the metal fitting body 21. In the circumferential direction of the branching member 30, three screw holes 32 penetrating with a predetermined phase angle are formed. The tip of the rod portion 12 of the pooling eye main body 11 is screwed into the screw hole 32. The other connecting structure between the pulling member 20 and the branching member 30 is not limited to the illustrated example. For example, an engagement recess or a hole formed in the metal fitting body 21 or the branching member 30 of one pulling member is used. A simple structure including the fitting portion and the convex portion or the protruding portion formed on the other branch member 30 or the metal fitting main body 21 of the pulling member can be employed. Further, although the branch member 30 is provided with the screw hole 32, it may be a simple insertion hole through which the rod portion 12 of the pooling eye main body 11 is inserted.

(Effects of the first embodiment)
According to the first embodiment described above, the following effects are obtained.
(1) The length of the skirt portion 14 of the pooling eye main body 11 is longer than the length of the compression portion 13 by not providing a pen rig portion on the cable insulator 42, and narrowing the end of the cable sheath 43 on the outer periphery thereof The waterproof portion 26 is formed on the outer periphery of the skirt portion 14 and waterproofed with a solid waterproof tape 25, so that the gap between the end of the cable sheath 43 and the cable conductor 41 is simple and short. It can be tightly and airtightly sealed over time, and the production efficiency is improved or improved, which is suitable for the production process at the production site.
(2) By adopting the solid waterproof tape 25 for the waterproof portion 26, the waterproof state between the end of the cable sheath 43 and the cable conductor 41, in particular, the close contact state between the cable sheath 43 and the skirt portion 14 is easy. Therefore, sufficient waterproof performance can be expected.
(3) The reduced pooling eye 10 having the waterproof portion 26 using the solid waterproof tape 25 can be attached to one end or both ends of the cable at the start or end of cable production quickly without reducing the manufacturing speed in the pooling eye mounting operation. It is possible to respond to installation requests.
(4) Further, since the cable insulator 42 to be removed has a structure in which no pen rig portion is provided, the length of the skirt portion 14 of the pooling eye main body 11 can be increased, and the end of the cable sheath 43 can be narrowed down while the conventional pooling eye is narrowed. Therefore, both reduction in size and waterproof performance can be satisfied.

[Second Embodiment and Third Embodiment]
FIGS. 3A to 3C are configuration examples of the pooling eye body according to the second embodiment, and FIGS. 4A to 4C are configuration examples of the pooling eye body according to the third embodiment. Respectively. In these drawings, substantially the same members as those in the first embodiment are given the same member names and symbols. Therefore, a detailed description of substantially the same members as those in the first embodiment is omitted.

  3 (a) to 3 (c), the difference from the first embodiment is that the skirt portion 14 of the pooling eye main body 11 is formed to have a smaller outer diameter than the compression portion 13 in the first embodiment. In the second embodiment, the outer diameter of the skirt portion 14 of the pooling eye main body 11 is formed to have the same diameter as that of the compression portion 13 in the second embodiment. As long as the inner diameter of the skirt portion 14 is formed larger than the inner diameter of the compression portion 13, the outer diameter of the skirt portion 14 may be the same as that of the compression portion 13. According to the illustrated example, the compression portion 13 and the skirt portion 14 are formed to be connected via an inclined step 18 in which only the inner peripheral surface is expanded and inclined. The inner diameter of the skirt portion 14 is set larger than that of the skirt portion 14 of the pooling eye main body 11 of the first embodiment shown in FIG.

  In the pooling eye main body 11 according to the third embodiment shown in FIGS. 4A to 4C, the skirt portion 14 of the pooling eye main body 11 is formed to have a larger outer diameter than the compression portion 13. This is different from the first embodiment and the second embodiment. According to the illustrated example, the compression portion 13 and the skirt portion 14 are formed by connecting the inner peripheral surface and the outer peripheral surface via inclined steps 18 and 18 in which the inner peripheral surface and the outer peripheral surface are inclining and expanding. The inner diameter of the skirt portion 14 is set larger than that of the skirt portion 14 shown in FIG. Even in the third embodiment, if the inner diameter of the skirt portion 14 is formed larger than the inner diameter of the compression portion 13 of the pooling eye body 11, the outer diameter of the skirt portion 14 is changed to the outer diameter of the compression portion 13. You may set larger than.

(Effect of 2nd Embodiment and 3rd Embodiment)
According to the second embodiment and the third embodiment, the outer diameter of the skirt portion 14 can be formed to be the same or larger than the outer diameter of the compression portion 13, so that it is applicable to cables of various cable sizes and voltage classes. it can.

  In addition, when laying a cable in underground conduits, caves, etc., there are a case where a single-core cable is pulled in and a case where a plurality of cables are pulled in and laid. The reduced pooling eye according to the present invention is a pooling eye main body as long as it satisfies a waterproofed structure that ensures waterproofness between the skirt portion and the cable sheath that are longer than the length of the compression portion. There are no particular restrictions on the number of cables stored, the number of pooling eye bodies, the material, and the like. Therefore, the present invention is not limited to the first embodiment, the second embodiment, the third embodiment, and the illustrated examples, and various design changes can be made without departing from the spirit of the invention. It is.

DESCRIPTION OF SYMBOLS 10 Reduction | restoration pooling eye 11 Pooling eye main body 12 Rod part 12a, 31 External screw 12b Split pin hole 13 Compression part 14 Skirt part 15, 20a Step 16 Washer 17 Tightening nut 18 Inclination step 20 Pulling member 21 Metal body 21a Hemispherical head 21b Cylindrical body 22 Flange portion 22a Insertion hole 23 Storage space 23a Small diameter storage portion 23b Large diameter storage portion 23c Internal screw 23d Screw mounting hole 24 Binding wire 25 Waterproof tape 26 Waterproof portion 30 Branch member 32 Screw hole 40 Power cable 41 Cable conductor 42 Cable insulator 43 Cable sheath 44 Thin section of cable insulator

Claims (3)

  A cylindrical compression portion that compresses and fastens the end of the cable conductor that is exposed by removing the cable sheath from the cable end portion without removing the cable insulation into a tapered shape, and formed at one end of the compression portion A rod-shaped rod portion, and a pooling eye main body having a cylindrical skirt portion extending in the cable longitudinal direction at the other end of the compression portion and longer than the compression portion, at least in the skirt portion The reduced pooling eye is characterized in that the portion of the cable sheath remaining from the molding of the cable end portion is narrowed on the outer periphery of the skirt portion, and the waterproofing portion is waterproofed.   The reduced pooling eye according to claim 1, wherein the waterproof portion is formed of a waterproof tape or a shrinkable tube.   The reduced pooling eye according to claim 1, wherein an outer diameter of the skirt portion is formed with an arbitrary dimension with respect to an outer diameter of the compression portion.