JPH11266524A - Pre-molded insulation pressing device of prefabricated joint for cv cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a construction which facilitates assembly and enables size reduction. SOLUTION: A fixed ring 28 is supported by a case 2. A distance between a pressing ring 39 and a pressing sleeve 25 is made freely adjustable by a pressing screw 41 which is screwed on the fixed ring 28. Compression coil springs 30 are provided around guide rods 29 between the fixed ring 28 and the pressing sleeve 25, and between the pressing 39 and the pressing sleeve 25. An elastic force applied to the pressing sleeve 25 through the compression spring 30 is adjusted by the pressing screw 41.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a pre-molded insulator pressing device for a prefabricated connection portion for a CV cable according to the present invention.
The present invention relates to an improvement in a device for pressing a pre-molded insulator incorporated in a prefabricated connection portion for connecting ends of a CV cable used as an underground power transmission line.

[0002]

2. Description of the Related Art A prefabricated connection as shown in FIG. 6 has conventionally been used to connect the ends of CV cables constituting an underground power transmission line. The prefabricated connection shown in FIG. 6 converts one CV cable 1 into two CV cables 1, 1 (or conversely, two CV cables 1, 1 into one CV cable 1). This shows a structure called a Y joint for connection. First, the structure of the prefabricated connection portion will be described.

The case 2 includes a main body 3, a first end plate 4,
Each of them comprises three insulating cylinders 5, 5 and second end plates 6, 6 corresponding to the number of CV cables 1, 1 to be connected. The main body 3 is made of metal and is formed in a cylindrical shape, and a first annular end plate 4 made of metal is screwed and fixed to an opening of one end (the left end in FIG. 6) of the main body 3. ing. Then, the CV cable 1 and the CV cable 1 are respectively connected to the center of the first end plate 4 and the other end (the right end in FIG. 6) of the main body 3.
Three circular openings 7, 7 for inserting one connection end are provided. Each of the insulating cylinders 5, 5 each formed into a short cylindrical shape by an insulating material such as an epoxy resin, is fixed by screws around the openings 7, 7.
Further, each of the second end plates 6, 6 is connected to each of the insulating cylinders 5, 5,
Are screwed and fixed to the outer edge (right edge in FIG. 6).

[0004] Inside the case 2 constructed as described above,
An insulating molded article 8 made of an insulating material such as an epoxy resin is held and fixed. That is, the insulating molded article 8 is fixed in the case 2 by screwing an end portion of the insulating molded article 8 to a portion near the inner peripheral surface of each of the second end plates 6, 6. A conductor connector 9 made of a metal having good conductivity such as copper is embedded and supported in such an insulating molded product 8. The conductor connector 9 is provided with three connection recesses 10, 10 corresponding to the number of the CV cables 1, 1 to be connected, facing the openings 7, 7 respectively. In the illustrated example, each of the connection concave portions 10 and 10 is formed as a tapered hole whose inner diameter becomes smaller from the opening to the back.

[0005] Each of the CV cables 1 and 1 is formed by covering the periphery of a conductor 11 with an insulating layer 12. At a connection portion, an end of the conductor 11 protrudes from an end of the insulating layer 12. ing. The periphery of the insulating layer 12 is covered with a shield wire 13, and the periphery of the shield wire 13 is covered with a surface covering 14 made of an insulating material. The shield wire 13 is grounded via studs 15 and 15, which will be described later, and the second end plates 6 and 6.

The conductor 11 of each of the CV cables 1 and 1
Is connected to the conductor connector 9 via a connection sleeve 16 as shown in FIGS. This connection sleeve 16 made of a metal having good conductivity such as copper has a first half (the first half in the insertion direction into the connection recess 10 as shown in FIG. 7).
The outer peripheral surface is an inclined surface inclined in the same direction as the inner peripheral surface of the connection concave portion 10, and a receiving-side inclined surface 17 whose outer diameter decreases toward the base end edge is formed on the outer periphery of the intermediate portion. doing.
A plurality of slits 18 are formed in the connection sleeve 16 at both front and rear edges so that the diameter can be elastically contracted. Such a connection sleeve 16 is inserted into each of the connection recesses 10 together with the tip of the conductor 11 in a state of being fitted over the tip of the conductor 11.

[0007] The inner and outer peripheral surfaces of the connection sleeve 16 and the outer periphery of the end of the conductor 11 are fixed by pressing and fixing sleeves 19 screwed to the opening ends of the connection recesses 10 as shown in FIGS. The surface and the inner peripheral surface of the connection recess 10 are in close contact with each other. Pressing and fixing sleeve 19
The push-side inclined surface which engages with the receiving-side inclined surface 17 on the distal end surface (the left end surface in FIG. 9) of a male screw which is screwed with an internal thread formed on the inner peripheral surface of the opening end of the connection concave portion 10 on the outer peripheral surface. Face 20
Are formed respectively. When such a pressing and fixing sleeve 19 is screwed into the opening end of each of the connection recesses 10 and further tightened, the pressing and fixing sleeve 19 causes the connection sleeve 16 to face the inside of each of the connection recesses 10. Press. Then, based on the engagement between the outer peripheral surface of the first half portion of the connection sleeve 16 and the inner peripheral surface of the concave portion 10 for connection and the engagement between the inclined surface 17 on the receiving side and the inclined surface 20 on the pushing side, the connection sleeve 16 is formed. Is pushed into the connection recess 10 while reducing the diameter. As a result, the inner and outer peripheral surfaces of the connection sleeve 16, the outer peripheral surface of the end of the conductor 11, and the connection recess 1
The inner peripheral surfaces of the conductors 0 are in close contact with each other to ensure a conductive state between the end of the conductor 11 and the conductor connector 9.

A part of the insulating molded article 8 which is located around the end of the insulating layer 12 is inclined in such a direction that the inner diameter decreases toward the connection recesses 10, 10. One inner diameter side tapered surface 22 is formed.
In the state where the end of the conductor 11 and the conductor connector 9 are connected as described above, the first inner diameter side tapered surfaces 22, 2,
The gap existing between the insulating layer 2 and the insulating layer 12 is closed by the pre-mold insulators 21 and 21. Each of these pre-mold insulators 21 is a combination of an insulating portion made of EP rubber and a semiconductive portion made of EP rubber to which carbon is added, and has a shape like an abacus ball stretched in the axial direction. A first outer diameter side tapered surface 23 which can be in close contact with each of the first inner diameter side tapered surfaces 22 is formed in one half in the axial direction of each of the pre-mold insulators 21, 21. or,
On the other half in the axial direction of each of the pre-mold insulators 21, 21, a second outer diameter side tapered surface 24 is formed which is inclined in a direction in which the outer diameter decreases as the distance from each of the connection recesses 10, 10 increases. doing.

Each of the pre-mold insulators 21, 2 as described above
1 are pressed by the pressing sleeves 25 toward the first inner diameter side tapered surface 22. The inner peripheral surface of each of these pressing sleeves 25 made of fiber reinforced plastic or the like is a second inner diameter side tapered surface 26 inclined in the same direction as the second outer diameter side tapered surface 24. It is arranged around the radial side tapered surface 24. Each of the pressing sleeves 25 is pressed toward the pre-mold insulator 21 by pressing means 27.

The pressing means 27, 27 are provided between the second end plates 6, 6 and the pressing sleeves 25, 25. Each of these second end plates 6, 6 has a fixed ring 28.
Are supported by a plurality of studs 15, 15, respectively. Further, at the base end surface of each pressing sleeve 25, that is, at a plurality of circumferential positions on the end surface opposite to the second inner diameter side tapered surface 26, the base end portions of a plurality of guide rods 29, 29 are provided. Is fixed. The distal end of each of the guide rods 29 is inserted into a guide hole (not shown) formed at a portion near the inner diameter of each of the fixed rings 28. Further, compression coil springs 30, which are pressing springs, are provided around the guide rods 29, between the fixed rings 28 and the pressing sleeves 25.

Each of the pressing sleeves 25, 25 is pressed against each of the pre-mold insulators 21, 21 by the pressing means 27, 27 respectively configured as described above.
The first inner diameter side tapered surface 22 and the first outer diameter side tapered surface 23 are in close contact with the inner peripheral surface of the pre-mold insulator 21 and the outer peripheral surface of the end of the insulating layer 12 without any gap. . For this reason, the insulation between the insulating layer 12 and the insulating molded article 8 is not impaired due to the existence of the gap.
In particular, the compression coil springs 3
0, 30 are incorporated, so that the pre-molded insulator 2
1 can be prevented from forming a gap between the inner peripheral surface 1 and the outer peripheral surface at the end of the insulating layer 12. The pressing force of the pressing means 27, 27 against the pressing sleeves 25, 25 changes the positions of the nut 31 and the lock nut 32 screwed to the tips of the studs 15, 15 and the fixed ring. 28 and the distance between the second end plate 6 and the compression coil springs 3
It is adjusted by changing the compression amount of 0, 30.

Each of the insulating cylinders 5 and 5 is
Body 3 and a cover 3 that covers the pressing means 27, 27
3 and 33 are isolated from each other so that when a failure such as insulation failure occurs, the location of the failure can be specified. For this purpose, the body 3 and the covers 33,
33 are independently grounded.

[0013]

In the case of the conventional structure as described above, not only the assembling work is troublesome, but also the outer diameter becomes large and the installation space is required. That is,
When assembling the pressing means 27, 27, a plurality of studs 15, 1 provided for each of the pressing means 27, 27 are provided.
5 and the nut 31 and the lock nut 32
All the connections must be made at the site where the CV cables 1 and 1 are connected (such as inside an underground common groove), and the assembling work of the prefabricated connection portion at the site becomes complicated.

Further, since the studs 15, 15 are further arranged around the plurality of guide rods 29, 29,
The outer diameter of each of the pressing means 27, 27 is increased. It is necessary to cover each of these pressing means 27, 27 with a cover 33, and to further wrap a protective tape around each of the covers 33, 33. In the case of the Y joint as shown in FIG. 6, the outer diameter of each of the pressing means 27, 27 is increased, and if the outer diameter of the cover 33 covering each of the pressing means 27, 27 is increased, (the right side of FIG. (Existing) the space between the two covers 33, 33 provided in parallel is reduced,
The work of winding the protective tape around these covers 33, 33 becomes troublesome. The pre-molded insulator pressing device of the prefabricated connection portion for a CV cable according to the present invention has been invented to solve any of the above-mentioned disadvantages.

[0015]

According to the present invention, there is provided a pre-molded insulator pressing apparatus for a prefabricated connection for a CV cable according to the present invention. An insulating molded product, a conductor connector embedded in the insulating molded product, a connection recess provided in the conductor connector, and a conductor surrounded by an insulating layer, and an end of the insulating layer. A CV cable having an end portion of the conductor protruding from the above, a connection sleeve provided between an outer peripheral surface of the end portion of the conductor and an inner peripheral surface of the connection concave portion, and a part of the insulating molded product. A first inner diameter side tapered surface provided in a portion located around the end of the insulating layer and inclined in a direction in which the inner diameter becomes smaller toward the connection recess, and fitted around the end of the insulating layer; Pre-molded insulator and A first outer diameter side tapered surface which is formed on one half in the axial direction of the metal insulator and which can be in close contact with the first inner diameter side tapered surface, and is formed on the other half in the axial direction of the premolded insulator. Further, a second outer diameter side tapered surface inclined in a direction in which the outer diameter becomes smaller as the distance from the connection concave portion increases, and a second inclined inner surface in the same direction as the second outer diameter tapered surface. A pressing sleeve which is an inner diameter side tapered surface and is arranged around the second outer diameter side tapered surface, and pressing means for pressing the pressing sleeve toward the pre-mold insulator is provided. In some cases, the above-mentioned insulating molded product is exposed in a case other than being held in a case.

In particular, in the pre-molded insulator pressing device for a prefabricated type connecting portion for a CV cable according to the present invention, the pressing means is supported by another part such as the case or a part of an insulating molded product. A fixed ring disposed around the CV cable, a press ring provided between the fixed ring and the pre-molded insulator so as to be displaceable in the axial direction of the CV cable, A plurality of compression springs provided between the pre-mold insulator; a plurality of screw holes formed at a plurality of circumferential positions of the fixed ring in an axial direction of the CV cable; And a plurality of pressing screws each of which is screwed into a hole and one end surface of which is in contact with one surface of the pressing ring.

[0017]

The pre-molded insulator pressing device of the prefabricated type connecting portion for a CV cable according to the present invention configured as described above presses the pre-molded insulator with a pressing sleeve, and forms a contact between the insulating molded product and the insulating layer of the CV cable. The gap between them is eliminated, and the insulation between the insulating molded product and the insulating layer is reliably ensured. In particular, according to the pre-molded insulator pressing device of the prefabricated connection portion for a CV cable of the present invention, not only the assembling work on site can be reduced to facilitate the assembling work, but also the outer diameter can be reduced. Installation space can be reduced.

[0018]

1 to 5 show an example of an embodiment of the present invention. The feature of the present invention relates to the structure of the pressing device for elastically pressing the pressing sleeve 25 toward the pre-mold insulator 21 in the axial direction. The entire structure of the prefabricated connection portion for a CV cable incorporating this pressing device is the same as the conventional structure shown in FIG. 6 described above, for example. The following description focuses on the features of the present invention.

A pair of legs 34, 34 is formed from two circumferentially opposite sides of the outer peripheral edge of the fixed ring 28 constituting the pressing device.
Are extended in the same axial direction. A locking portion 35 is provided at the tip of each of the legs 34, 34 so as to protrude outward in the diameter direction of the fixed ring 28.
On the other hand, two circumferentially opposite positions of the inner peripheral edge of the second end plate 6 corresponding to an annular portion fixed to the case according to claim 2 and fixed to the distal end of the insulating cylinder 5 by screwing. In
A notch 36 that can pass through each of the locking portions 35, 35;
36 are provided. The fixed ring 28 is supported on the case 2 by rotating these locking portions 35, 35 in the circumferential direction after passing through the notches 36, 36.

That is, the fixed ring 2 is
At the time of supporting and fixing the support 8, first, as shown in FIG. 3, the locking portions 35, 35 and the notches 36, 36 are aligned with each other. In this aligned state, the engaging portions 35, 35 are oriented such that the insides of the notches 36, 36 are directed toward the insulating cylinder 5 from the side opposite to the insulating cylinder 5 as shown in FIG. Pass from right to left. Thereafter, the fixed ring 28 is rotated in the circumferential direction, and the locking portions 35, 35 are rotated.
And the respective notches 36, 36 are shifted in phase in the circumferential direction. In this state, the locking portions 35, 35 are moved by the elasticity of the compression coil springs 30, 30, which will be described later, to the inner side surface of the second end plate 6 (the side surface on the insulating cylinder 5 side, the left side surface in FIG. 1).
, And is supported and fixed to the case 2.

Screw holes 37, 37 are provided at four positions at equal intervals in the circumferential direction of the fixed ring 28, and a plurality of screw holes 37, 37 are provided between the screw holes 37, 37 adjacent in the circumferential direction. In this case, three support holes 38 are formed at equal intervals in the circumferential direction, and are formed in the axial direction. The same number (16 in the illustrated example) of the guide rods 29, 2 as the total number of the screw holes 37, 37 and the support holes 38, 38 are provided on the base end surface of the pressing sleeve 25.
The base end portion 9 (the left end portion in FIGS. 1 and 2) is fixedly connected at equal intervals in the circumferential direction. These guide rods 29, 29 are arranged in parallel with each other.

The pressing sleeve 25 and the stationary ring 2
8, a ring-shaped pressing ring 39 is provided in the axial direction (FIGS. 1 to 1).
2 (left and right directions). In the pressing ring 39, guide holes 40 for slidably inserting the guide rods 29, 29 are formed in the same phase as the guide rods 29, 29. Such a press ring 3
9, each of the guide rods 29,
29 is disposed between the pressing sleeve 25 and the fixed ring 28 in a state where it is inserted. In this state, the distal ends of the guide rods 29, 29 (right ends in FIGS. 1 and 2).
Are inserted into support holes 38, 38 formed in the fixed ring 28 or other guide holes 42, 42 formed in the center of pressing screws 41, 41 described later.

Therefore, in a state where the pre-mold insulator pressing device of the present invention is assembled, the plurality of guide rods 2 are provided.
Part of 9, 29 (12 out of 16 in the example shown)
The guide rods 29, 29 are supported at both ends by the pressing sleeve 25 and the support holes 38, 38, respectively. The remaining (four in 16 in the example shown) guide rods 29, 29 are supported at both ends by the pressing sleeve 25 and the guide holes 42, 42, respectively. Further, around the guide rods 29, 29, the base end surface of the pressing sleeve 25 and the pressing ring 39
The compression coil springs 30, 30 are mounted between them. And each of these compression coil springs 30, 30
Accordingly, the pressing sleeve 25 can be pressed toward the pre-mold insulator 21 freely.

Further, pressing screws 41, 41 as shown in FIG. 4 are screwed into the respective screw holes 37, 37 formed at four places in the circumferential direction of the fixed ring 28. Each of the pressing screws 41 has a male screw formed on the outer peripheral surface thereof, and the above-mentioned another guide hole 42 formed at the center thereof. In addition, a square hole 43 having an inner peripheral surface formed in a hexagonal cylindrical shape is formed in a base end side (right end side in FIGS. 1 and 2) opening of the guide hole 42, and a tool such as a hexagon wrench is used. Press screw 4
1, 41 are rotatable. Each such pressing screw 4
1, 41 (the left end face in FIG. 1)
On one side. Therefore, each of the pressing screws 4
By rotating the pressure coil springs 1 and 41 and adjusting the amount by which the tips of the pressing screws 41 and 41 protrude from the inner surface (the left side surface in FIGS. 1 and 2) of the fixed ring 28, the compression coil springs 30 , 30 can be adjusted. In addition, each of the pressing screws 4
A lock nut is screwed into a portion protruding from the outer surface of the fixed ring 28 at a base end portion of each of the fixing screws 28 to prevent the pressing screws 41, 41 from being accidentally rotated. I do.

According to the premold insulator pressing device for a prefabricated type connecting portion for a CV cable according to the present invention having the structure described above, the first outer diameter side tapered surface 23 formed on the premold insulator 21 is insulated. The gap between the first inner diameter side tapered surface 22 formed on the molded product 8 and the gap between the inner peripheral surface of the pre-molded insulator 21 and the outer peripheral surface of the insulating layer 12 constituting the CV cable 1 are determined. Thus, insulation between the insulating molded product 8 and the insulating layer 12 can be reliably achieved. That is, by rotating the pressing screws 41, 41 to adjust the distance between the pressing ring 39 and the pressing sleeve 25 and adjusting the elasticity of the compression coil springs 30, 30, the pressing sleeve 25 By properly pressing the pre-mold insulator 21, the pre-mold insulator 21 is pressed in the axial direction and shrunk inward in the diametrical direction to eliminate the gap between the surfaces.

In particular, according to the pre-molded insulator pressing device of the prefabricated type connecting portion for CV cable of the present invention, not only the assembling work on site can be reduced to facilitate the assembling work, but also the outer diameter can be reduced. The installation space can be reduced by making it smaller.
That is, the pressing sleeve 25, the pressing ring 39, the fixed ring 28, the compression coil springs 30, 30, the pressing screws 41, 41, and the guide rod 2 which constitute the pressing means of the pressing device of the present invention.
9 and 29 can be assembled as a pressing unit 44 in a factory or the like in the state shown in FIG. 2 in advance. Then, as described above, the operation of mounting the pressing unit 44 on the case 2 is performed by connecting the locking portions 35, 35 to the cutout portions 36, 3
6 can be easily performed by rotating in the circumferential direction after passing. For this reason, the work to be performed in the underground common ditch or the like can be reduced. Further, with the pressing unit 44 attached and the pre-mold insulator 21 pressed, the cover 3
Before mounting the CV cable 3 (in a state where the cover 33 previously fitted to the CV cable 1 is shifted toward the center of the CV cable 1), the compression coil springs 30, 30
Can be visually confirmed.

Further, as in the conventional structure shown in FIG. 6, the studs 1 are provided around the guide rods 29, 29.
Since it is not necessary to dispose another member such as 5, 15 or the like, the diameter of the pressing device and the cover 33 covering the pressing device can be reduced. For this reason, for example, when the present invention is applied to a Y-joint as shown in FIG. 6, the work of winding the insulating tape around the cover 33 by widening the interval between the adjacent covers 33 can be easily performed. become. Alternatively, if the spacing between the adjacent covers 33 is the same,
The pitch of the pair of CV cables 1 and 1 can be shortened, and the outer diameter of the prefabricated connection portion for CV cables can be reduced.

[0028]

The pre-molded insulator pressing device of the prefabricated type connecting portion for CV cable according to the present invention is constructed and operates as described above. By reducing the outer diameter of the pressing device portion, the installation space can be reduced and the work of winding the insulating tape can be facilitated. For this reason, the installation space is small,
Moreover, it is possible to contribute to the realization of a prefabricated connection portion for a CV cable in which assembly work is easy.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing an example of an embodiment of the present invention.

FIG. 2 is a half cutaway side view showing a pressing unit constituted by a pressing sleeve, a pressing ring, a fixed ring, a compression coil spring, a pressing screw, and a guide rod.

FIG. 3A is a partially omitted illustration of a state at the time of assembly;
-A view.

FIG. 4 is a perspective view of a pressing screw.

FIG. 5 is a perspective view of a fixed ring.

FIG. 6 is a cross-sectional view showing an example of a prefabricated connection part for a CV cable incorporating a pre-molded insulator pressing device of a conventional structure.

FIG. 7 is a sectional view of a connection sleeve.

FIG. 8 is an end view seen from the right side of FIG. 7;

FIG. 9 is a sectional view of a pressing and fixing sleeve.

FIG. 10 is an end view seen from the right side of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 CV cable 2 Case 3 Main body 4 First end plate 5 Insulation cylinder 6 Second end plate 7 Opening 8 Insulation molding 9 Conductor connector 10 Connection recess 11 Conductor 12 Insulating layer 13 Shield wire 14 Surface covering 15 Stud 16 Connection sleeve 17 Receiving-side inclined surface 18 Slit 19 Press-fixing sleeve 20 Push-side inclined surface 21 Pre-mold insulator 22 First inner diameter side taper surface 23 First outer diameter side taper surface 24 Second outer diameter side taper surface 25 Pressing sleeve 26 Second inner diameter side tapered surface 27 Pressing means 28 Fixed ring 29 Guide rod 30 Compression coil spring 31 Nut 32 Lock nut 33 Cover 34 Leg 35 Locking portion 36 Notch 37 Screw hole 38 Support hole 39 Pressing ring 40 Guide Hole 41 Press Screw 42 Guide Hole 43 Square Hole 44 Press Unit

Claims (2)

[Claims] An apparatus for pressing a pre-molded insulator incorporated in a prefabricated type connection for a CV cable, comprising:
A fixed ring disposed around the CV cable while being supported elsewhere, and a press ring provided between the fixed ring and the pre-mold insulator so as to be displaceable in the axial direction of the CV cable; A plurality of compression springs provided between the pressing ring and the pre-mold insulator; and a plurality of screw holes formed in the circumferential direction of the fixed ring at a plurality of positions in the axial direction of the CV cable. And a plurality of pressing screws each of which is screwed into each of the screw holes and one end surface of which is in contact with one surface of the pressing ring.
Pre-mold insulator pressing device for pre-fabricated connection part for cable. 2. A plurality of legs extending in the same axial direction from a plurality of circumferential portions of an outer peripheral edge of the stationary ring, and a state in which the legs protrude outward in a diametrical direction of the stationary ring from tips of the legs. And a notch formed on the inner peripheral edge of the annular portion fixed to the case holding the insulating molded product and capable of passing through each of the locking portions. The respective locking portions are supported by the case by rotating in the circumferential direction after passing through the respective notches, and are supported on the end surface of the pressing sleeve on the side opposite to the second inner diameter side tapered surface. The base ends of a plurality of guide rods are connected and fixed at a plurality of locations in the circumferential direction, and the distal ends of these guide rods are inserted into guide holes formed in the center of each pressing screw, so that the pressing Each compression coil spring, which is a spring, The apparatus for pressing a pre-molded insulator of a prefabricated connection part for a CV cable according to claim 1, wherein