JPH0266815A - Bushing device and its manufacture - Google Patents

Abstract

PURPOSE:To increase the reliability of the airtightness of the bushing device and reduce its cost and also simplify its manufacturing process, by molding a mold cone integrally with a bushing, a conductor and a conductive wire. CONSTITUTION:A bushing 5 is disposed over the outer periphery of the electric conductor 2 of a combination conductor 3, and a clearance is provided between the inner wall 5b of the through hole provided through the bushing 5 and the combination conductor 3 so that a mold cone material is capable of flowing therethrough. The portion where the mold corn 4 extends over both the outer edge portion 5a of the bushing 5 and the insulating covering portion 1b of the combination conductor 3, and the clearance between the inner wall 5b of the through hole of the bushing 5 and the combination conductor 3 are integrally molded together. The mold material inserted into the above clearance space extends over a long path and firmly combines the bushing 5 with conductor 3 so that external forces or environmental conditions have little influence thereon; it can therefore be held in a hermetically stable state over a long period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a bushing device for power distribution equipment and a method for manufacturing the same.

[Prior Art] Conventionally, bushing devices for overhead power distribution equipment have been manufactured as follows.

As shown in FIG. 4(A), the insulation coating 1 at the end of the conductor 1
(b) is attached to one end of the rod-shaped conductor 2 on the exposed core wire 1a.
The conductor 3 is formed by inserting the conductor into the insertion hole and compressingly connecting it.

As shown in FIG. 4(B), a malt cone 4 is integrally molded across the end of the conductor 2 and the end of the insulating coating 1b of the conductive wire 1. As shown in FIG.

As shown in FIG. 4(c), an insulator tube 5 is arranged around the outer periphery of the conductor 2 of the combination conductor 3, and the outer end 5a of the insulator tube 5 is attached to the inner wall 5b of the through hole adjacent to the outer end 5a. The proximal end of the mold cone 4 is fitted to the end via the adhesive layer 6 and bonded together.

As shown in FIG.
A gasket or an O-ring 10 is interposed between the flange 5f of the insulator pipe 5 and the equipment container 9, and the flange 5f is tightened using a bolt 12 via a metal fitting 11.
By tightening with
be pulled. Furthermore, between the inner end 5c of the insulator tube 5 placed in the equipment container 9 and the conductor 2, a sealing end plate 14 is tightened by means such as screw tightening via a gasket or an O-ring 13. It is sealed by fixing the plate.

The equipment container 9 of the high-voltage power distribution equipment 8 as described above contains oil, arc-extinguishing gas (SF6 gas), etc., to ensure required interrupting characteristics and electrical insulation performance. Therefore, the equipment container 9 is required to have a high degree of airtightness.

A tracking-resistant insulated wire is used as the conductor 1 of the equipment container 9, and a molded cone 4 and an insulated pipe 5 are provided at the part where the conductor 1 passes through the equipment container 9 from the viewpoint of electrical safety and salt damage resistance. The bushing device 7 is provided with a bushing device 7.

[Problem to be solved by the invention] However, the insulator tube 5 is made of porcelain or ceramic,
In general manufacturing methods, there is large variation in dimensions (around 10% of standard dimensions), and as a result, mold cone 4
In order to bond the insulator tube 5, it requires machining (cutting, polishing) the outer end of the insulator tube 5 to increase the adhesive strength, improving the precision of the bonding surface of the mold cone 4, and wiping the bonding surface. If the accuracy is not sufficient, a large clearance will occur between the adhesive surfaces of the insulator tube 5 and mold cone 4, the adhesive layer 6 will become thicker, the adhesive strength will lack stability, and voids will occur, causing the adhesive layer 6 to become thicker. This caused problems such as poor airtightness.

Furthermore, when adhering the insulator tube 5 and the mold cone 4, conventionally, the insulator tube 5 and the mold cone 4 are subjected to surface treatment for adhesion, an adhesive with a short pot life is used, and a contact point is hardened. In order to accelerate the process, it is necessary to maintain the temperature at a high temperature, which complicates the manufacturing process and requires extra equipment, resulting in an increase in product cost.

In addition, the inner end 5C of the insulator tube 5 inside the equipment container 9 is machined (
cutting, polishing) to improve flatness and surface roughness accuracy.
It is necessary to enhance the sealing effect of the packing or O-ring 13, and special cutting tools such as a diamond cutter are required to machine the insulator tube 5, which takes processing time, which also increases the product cost. was occurring.

An object of the present invention is to provide a bushing device with a structure that has high reliability in airtightness and can reduce costs.

Another object of the present invention is to provide a method for manufacturing a bushing device that can easily manufacture a bushing device with a structure that has high reliability in airtightness and can be manufactured at low cost.

[Means for Solving the Problems 1] In order to achieve the above object, the present invention uses the following means.

The bushing device according to claim (1) includes a combination conductor in which a conductor is connected to the tip of the conductor, an insulator tube arranged around the outer periphery of the combination conductor, and an outer end of the insulator tube and the conductor of the combination conductor. In the bushing device, the molded cone includes an outer end of the insulator tube, a portion of the combined outgoing conductor that extends over the conducting wire, and an inner wall of the insulator tube through hole and the combined conductor. The method for manufacturing a bushing device according to claim (2), characterized in that the space between the conductor and the conductor is integrally molded, includes the steps of: (a) stripping off the insulating coating at the end of the conductor to expose the core wire; Then connect the conductors and form a combination I! a step of forming a conductor; (l) a step of inserting the combined conductor that has passed through step (a) into a through hole of an insulator tube; and (c) a step of forming the insulator tube that has been combined through the two-culm step (b). and the combined conductor are placed in a mold, and the combination is placed between the outer end of the insulator tube and the insulating coating of the conductor, and between the inner wall of the through hole of the insulator tube and the combined conductor. (d) press-fitting unvulcanized rubber into the mold that has gone through step (c) and combining it with the outer end of the insulator tube; A T culm that fills the hollow-shaped space leading to the insulating coating portion of the conductor, the space surrounded by the inner wall of the through hole of the insulator tube, and the surface of the combined conductor, and vulcanizes the unvulcanized rubber. It is characterized by consisting of the following.

[Function] The J: sea urchin seven-root cone according to claim (1) is molded into a structure in which an insulator tube, a conductor, and a conducting wire are integrally molded.
However, not only the airtightness between the mold loan and the conducting wire and between the malt cone and the conductor, but also the airtightness between the malt cone and the porcelain tube can be improved, and the cost can be reduced to 1~. Moreover, the outer diameter of the mold cone can be brought into close contact with the inner wall of the through hole of the insulator, regardless of variations in the dimensions of the insulator. Furthermore, since a sufficient airtight connection with the seven-fold cone can be obtained within the insulator tube through-hole, there is less dependence on the airtightness between the insulator tube end and the malt cone end surface, and machining of the outer end of the insulator tube and mold cone This eliminates problems such as the accuracy of the contact surfaces, and also eliminates the need for mechanically working the inner end of the insulator tube and stopping it with a sealing end plate via a packing or an O-ring.

When manufactured as described in claim (2), a bushing device with high airtightness, low cost, and a cost of 1~ can be manufactured easily and with good reproducibility.

[Example] Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows an embodiment of a bushing device 7 according to the present invention. As shown in the figure, the core wire 1a with the insulating coating 1b removed from the end of the conductor 1 is inserted into the insertion hole 2a provided at the end of the rod-shaped conductor 2, and is compressed and connected to the combined conductor 3.
It consists of An insulator tube 5 is arranged around the outer periphery of the conductor 2 of the combination conductor 3, and a gap is provided between the through-hole inner wall 5b of the insulator tube 5 and the combination conductor 3 through which a mold cone material can flow. Then, the portion where the mold cone 4 spans the outer end 5a of the insulator tube 5 and the insulating coating portion 1b of the combination conductor 3, and the gap space between the through-hole inner wall 5b of the insulator tube 5 and the combination conductor 3 are integrally molded. It's been done.

The outer end 5a of the insulator tube 5 that contacts the mold cone 4 and the inner wall 5b of the through hole are unglazed surfaces, and the other outer surfaces 5c, 5d, 5e, and 5f are coated with a top coat. It has a medicinal quality. In this way, when the outer end 5a of the insulator tube 5 in contact with the mold cone 4 and the inner wall 5b of the m through hole are made into bisque fired surfaces and molded according to the shape, the mold cone 4 and the insulator tube 5 are The bond with the through-hole inner wall 5b of the insulator tube 5 is strong, and sufficient airtightness can be obtained without using an adhesive.
The malt material filled between the conductor and the combination conductor 3 has a long path and is strongly bonded to the above-mentioned wire, making it difficult to be affected by external forces or the external environment, so that stable airtightness can be maintained over a long period of time. Therefore, in the case of this bushing device 7, there is no need for machining on both end faces of the insulator tube 5, and for the sill end plate 14 and packing or O-ring 13, which were required in the past. Since a coating layer is provided on the outer surfaces 50 to 5f of the insulator tube 5 that do not come in contact with each other, it is possible to prevent moisture from entering.

In the above embodiment, if the molding material is filled between the through-hole inner wall 5b of the insulator tube 5 and the combined conductor 3 over the entire space, the bonding, adhesion, or airtightness will be ensured.
If the length of this space is sufficiently long, it is possible to partially omit filling. This filling can be omitted by adjusting the width of the filling end or adjusting the press-fitting pressure of the filling material.

FIG. 2 shows an example of a method for manufacturing the bushing device 7 according to the present invention. The steps of the manufacturing method of this example are as follows.

(2'-1): Strip the insulating coating 1b at the end of the conductor 1 to expose the core wire 1a, insert it into the insertion hole 2a provided at the end of the conductor 2, connect it by compression, and connect it to the combined conductor 3. The process of obtaining.

(2-2): A step of applying a primer treatment to the surface of the conductor 2 of the combination conductor 3 that has undergone the step of (2-1).

(13): Outer end portion 5a which is the unglazed surface of the insulator tube 5.

A step of applying a primer treatment to the inner wall 5b of the through hole.

(2-4): After the process of (2-2), the conductor 3 is inserted into the through hole of the insulator tube 5 that has undergone the process of (2-3).

(2-5): A process of setting the insulator tube 5 and the combined conductor 3 that have undergone the process of (2-4) into the mold 15. At this time, there is sufficient space between the cone-shaped space extending from the outer end 5a of the insulator tube 5 to the insulating coating portion 1b of the combination conductor 3, the through-hole inner wall 5b of the insulator tube 5, and the combination conductor 3 for the mold cone material to flow in. Create a spatial gap.

(2-6): Unvulcanized rubber is press-fitted from the injection hole 16 into the mold 15 that has gone through the process of (2-5), and the outer end 5a, which is the unglazed surface of the insulator tube 5, and the inner wall 5b of the through hole are formed. The surface of the combination conductor 3, especially the surface up to the insulation coating portion 1b of the conductor 1, and the mold 15
The process of filling the space surrounded by the inner surface of the rubber and vulcanizing the unvulcanized rubber by pressurizing it at high temperature.

(2-7): Step of releasing the bushing device 7 obtained in step (2-6>).

Outer end 5a of insulator tube 5 in contact with mold cone 4.

Since the inner wall 5b of the through hole is made of an unglazed surface and treated with a primer, it is firmly and closely bonded when the fluid mold rubber undergoes a vulcanization reaction, and the mechanical properties necessary for the joint between the mold cone 4 and the insulator tube 5 are achieved. It can exhibit electrical properties as well as hermetic sealing properties.

Further, since the surface of the conductor 2 is also subjected to primer treatment, it is tightly bonded by the vulcanization reaction, and the required airtight sealing properties can also be exhibited.

In FIG. 1, the outer end of the conductor 2 is the outer end 5 of the insulator tube 5.
The conductive wire 1 is connected to the leading end of the molded cone 4 so that a considerable part of the base of the molded cone 4 extends over the protruding portion of the conductor 2. In the conventional bushing device 7 as shown in FIG. 4, when the mold cone 4 is bonded to the end face of the insulator tube 5, when an external force is applied to the conductor 1, the force is applied to the mold cone 4 and the mold cone 4 and the insulator tube. There is a possibility that the adhesive layer 6 from the 5 will peel off, and the airtightness will be impaired. In order to prevent this, it is necessary to provide rigidity to the base of the molded cone 4, so by making the rigid conductor 2 protrude from the end face of the insulator tube 5,
Rigidity is given to the base of the mold cone 3 to prevent external force applied to the conductive wire 1 from reaching the adhesive part of the malt cone 4. In the case of the present invention as well, in order to prevent unnecessary external force from being applied to the joint between the molded cone 4 and the outer end 5a of the porcelain tube, resulting in a peeling force, it is preferable to configure the molded cone 4 as shown in FIG.

However, in the present invention, the mold cone 4 is filled not only in the outer end 5a of the insulator tube 5 but also in the through hole of the insulator tube, so that the gas leakage path is very long. 4, insulator tube 5, combination conductor 3
Since the bond is strong, the bond is unlikely to peel off under the influence of some external force, and even if it does peel off, it will only be partially separated and the airtightness will not be impaired. Therefore, the structure shown in FIG. 1 is not necessarily required, and even if the conductor 2 is drawn in from the outer end 5a of the insulator tube 5 as shown in FIG. 3, there is no problem in maintaining airtightness.

In the case of Fig. 1, the external force applied to the conductor 1 is received by the outer end of the conductor 2 as a fulcrum and absorbed by the elasticity of the molded cone 4, but in the case of Fig. 3, the external force applied to the conductor 1 is The outer end 5a of the insulator tube 5 is used as a fulcrum to stop the support, and the elasticity of the molded cone 4 absorbs it.

[Effects of the Invention] As explained above, according to the present invention, the following effects can be obtained.

If the mold cone is integrally molded with the insulator tube, the conductor, and the conductor as claimed in claim (1), the airtightness between the mold cone and the conductor and between the mold cone and the conductor can be improved. The airtightness between the mold cone and the insulator tube can be significantly improved by firmly bonding the mold cone to the surface of the insulator tube, and there is an advantage that costs can be reduced. In addition, since the mold is molded integrally to fit the IC1 insulator tube, the outer surface of the mold cone can be brought into close contact with the inner wall of the insulator tube, regardless of variations in the dimensions of the insulator tube, eliminating the need for an adhesive layer. J: Negative effects such as variations in adhesive strength can be avoided. Just like the two pairs, the molding material is filled into the insulator tube when the mold cone is integrally molded, and the bonding strength is great and the airtight bond is also sufficient, so separately place the combined conductor in the appropriate position inside the insulator tube. There is an advantage that there is no need to separately fill a filler such as an epoxy resin in order to maintain the through hole and maintain airtightness within the through hole.

Furthermore, since a sufficient airtight connection between the insulator and the molded cone can be obtained, there is an advantage that it is not necessary to machine the inner end of the insulator and seal it with a sealing end plate via a packing or an O-ring. be. As described above, according to claim (1) of the present application, it is possible to reduce the number of manufacturing steps and cost of the bushing device.

On the other hand, according to claim (2), a 4M bushing device that has high airtightness and can be manufactured at low cost can be easily manufactured with good reproducibility.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional side view of the upper half of a bushing device according to an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of the bushing device in a molded state in a mold showing a method for manufacturing the bushing device according to an embodiment of the present invention. FIG. 3 is a longitudinal cross-sectional side view of the upper half of a bushing device according to another embodiment of the present invention, FIG. FIG. 3 is a vertical cross-sectional view of a conventional bushing device in use. DESCRIPTION OF SYMBOLS 1... Conductor wire, 1a... Core wire, 1b... Insulation covering part, 2... Conductor, 3... Combination conductor, 4... Molded cone, 5... Insulator tube, 5a.・Outer end, 5b・
...Through-hole inner wall, 5C to 5f...Outer surface, 7...Bushing device, 8...Power distribution equipment, 9...Equipment container,
15...Mold.

Claims (2)

[Claims] (1) A combination conductor with a conductor connected to the tip of the conductor, an insulator tube placed around the outer periphery of the combination conductor, and a mold integrally formed over the outer end of the insulator tube and the outer periphery of the conductor of the combination conductor. In the bushing device, the molded cone includes an outer end of the insulator tube, a portion of the combined conductor that spans the conductor wire, and a space between the inner wall of the insulator tube through-hole and the combined conductor, which are integrally molded. A bushing device characterized by: (2) (a) Step of stripping the insulating coating at the end of the conductor to expose the core wire and connecting the conductors to form a combined conductor, and (b) converting the combined conductor that has passed through step (a) into a ceramic tube. (c) inserting the insulating tube and the combined conductor combined through the step (b) into a mold, inserting the insulating coating portion of the combined conductor from the outer end of the insulating tube; A cone-shaped space leading to
(d) placing an unvulcanized rubber into the mold after the step (c); and (d) setting the mold cone material between the inner wall of the through-hole of the insulator and the combined conductor. is press-fitted to fill the cone-shaped space extending to the outer end of the insulator tube and the insulating coating of the combination conductor, and the space surrounded by the inner wall of the through hole of the insulator tube and the surface of the combination conductor,
A method for producing a bushing device, comprising: a step of vulcanizing the unvulcanized rubber.