JPH04115720U - transformer bushing - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to improve the airtightness of terminals penetrating the transformer box wall and to provide an economical butsing. [Structure] The bushing 7a consists of a terminal 2A, an insulating cover 15 with excellent heat resistance and oil resistance, and an insulating molded product 16 integrated between them. It has a flange portion extending outside the box, and the flange portion is fixed to the outer surface of the transformer box with a tightening force via a packing 13, thereby maintaining a predetermined airtightness. The insulating molded product 16 is integrated with the insulating cover 15 and the terminal 2A by casting the insulating cover 15 as a molded product.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a transformer bushing.

0002

[Conventional technology]

Traditionally, the secondary terminals passing through the transformer are magnetically connected, as shown in Figures 3 and 4. Pass the terminal 2 through the hole in the insulator 1 made with a container, and tighten the packing 3 to the nut 4. It was tightened even more and was firmly attached to insulator 1.

0003 The tip of the terminal 2 has a hole into which the lead wire 5 is inserted. 2a is compressed and connected, heat-shrinkable tube 6 is attached to this part, and bushing 7 is shaped. It was completed.

0004 The bushing thus formed is fixed to the transformer body 8 on the circumference of the insulator 1. The spring 9 is installed in the recess provided in the A fixed fitting 10 was attached to a transformer box 12 with several screws 11. and insulator 1 A packing 13 is interposed between the transformer and the casing 12 to keep the transformer airtight.

[0005] In addition, in FIG. 3, 14 is a primary side lead wire.

[0006]

[Problem that the idea aims to solve]

The conventional terminal described above has the following problems.

[0007] (1) Use long lead wires to prevent them from becoming short even under various installation conditions. It is necessary to attach the lead wire.

[0008] (2) Compressing work is required to connect the terminal and lead wire, and this part requires installation of heat-shrinkable tubing for waterproof insulation.

[0009] (3) Because the bushing body is an insulator made of porcelain, it is weak against impact forces and is When installing the bushing on a column, special care must be taken to prevent the bushing from hitting the pillar mounting parts. It is essential.

0010 (4) The airtightness of the terminal depends on the packing attached to the terminal, and the airtightness of the terminal depends on the packing attached to the terminal. If the tightening condition of the packing cannot be checked inside and the tightening is incomplete, In this case, moisture from the atmosphere enters the transformer due to its breathing effect, significantly reducing the insulation properties of the transformer. There were cases where it was lowered.

[0011] The present invention was developed in consideration of the above points, and is highly reliable and economical. The purpose of this invention is to provide a transformer bushing that makes it possible to

0012

[Means to solve the problem]

The purpose of the above is to remove the bushing from the part that goes inside the transformer box on the front side of the bushing. The part of the flange that extends outside the box is made of heat-resistant and oil-resistant insulating material. A heat-resistant and weather-resistant insulating material is injected between an insulating cover of a predetermined thickness and a terminal. It is formed by integrating the edge material, and this integrated insulating molded product is used as a case for the insulating cover. Tighten and secure to the case through packing between the part of the flange that extends outside and the case. This can be achieved by establishing

[0013]

[Effect]

Since the above means is provided, the airtightness of the terminal is improved.

[0014]

【Example】

Hereinafter, the present invention will be explained based on the illustrated embodiments. Figures 1 and 2 show the main An example implementation of the scheme is shown. Note that parts that are the same as before are given the same symbols, so explanations will be omitted. Omit the description. In this embodiment, the bushing 7a is connected to the transformer box 1 on the surface of the bushing. The part that goes inside the box and some of the flange parts that go outside the box are made heat resistant and oil resistant. An insulating cover 15 of a predetermined thickness made of an insulating material and a terminal 2A are injected between them. It is made of an insulating material that is heat resistant and weather resistant. A part of the flange portion of the insulating molded product 16 that extends outside the box of the insulating cover 15 and the box 12 It was tightened and fixed to the case 12 with a packing 13 interposed therebetween. You can do it like this This improves the airtightness of the terminal 2A, resulting in excellent reliability and economy. It is possible to obtain a transformer pushing 7a that makes it possible to

[0015] That is, the bushing 7a enters the inside A of the transformer box 12, and a part of the bushing 7a enters the outside of the box 12. The outer surface of the flange portion that exits side B is coated with an insulating material with excellent oil resistance and heat resistance (for example, G The outer part B of the box 12 is For example, use EP (ethylene propylene) rubber, which has excellent weather resistance and heat resistance, to disconnect terminal 2A. By injection hardening molding between the edge cover 15 and integrating it, airtightness is ensured. can be maintained. In addition, as described above, a part of the insulating cover 15 is removed from the box 12. Extract it to the outside B, and put the flange part exposed outside in a box through the packing 13. Since it is tightened and fixed to the body 12, the tightening part including the packing 13 may be attacked by oil. There is no.

[0016] Also, one end of the terminal is threaded and the lead terminal inside the transformer is attached, and the other end is threaded. As shown in FIG. 2, the lead wire of the external lead wire 5a is The terminal 17 is connected by tightening the bolt 18. An insulating cover 19 is attached to the portion.

[0017] As described above, according to this embodiment, the following effects can be achieved.

[0018] (1) Since the terminal is integrally molded as an insulation molded product, there is no need to use packing. Sufficient airtightness is maintained.

[0019] (2) Fewer parts means fewer manufacturing processes and is highly economical.

[0020] (3) Compressing the lead wire is no longer necessary, and the lead wire part can no longer be compressed. It eliminates the need to maintain airtightness through packing, greatly improving reliability.

[0021] (4) The minimum length of the lead wire is required depending on the on-site situation, and the lead wire can be used as before. There is no need to cut or throw away the wire, making it highly economical.

[0022] (5) Can be made with the same shape and dimensions as conventional products and is compatible. Can be easily converted.

[0023]

[Effect of the idea]

As mentioned above, the present invention places the bushing inside the transformer box on the surface side of the bushing. Heat-resistant and oil-resistant insulation for the part that enters and the part of the flange that exits the box. A heat-resistant and weather-resistant material is injected between an insulating cover of a predetermined thickness made of wood and a terminal. It is formed integrally with an insulating material having a Packing is inserted between the part of the flange of the bar that protrudes outside the box and the box. Since the terminals are tightened and fixed, the airtightness of the terminals is improved, improving reliability and longevity. Thus, a transformer bushing can be obtained that is highly efficient.

[Brief explanation of drawings]

FIG. 1 is a partially vertical side view of an embodiment of a bushing for a transformer according to the present invention.

FIG. 2 is a front view of a transformer according to an embodiment of the transformer bushing of the present invention.

FIG. 3 is a front view of a transformer using a conventional transformer bushing.

FIG. 4 is a partially longitudinal side view of a bushing of a conventional transformer.

[Explanation of symbols]

2A terminal 5a External lead wire 7a Bushing 12 Transformer box 13 Packing 15 Insulation molded products

──────────────────────────────────────────────── ─── Continuation of front page (72) Creator Nobuo Masuoka Hitachi, 3-1-1 Sukegawa-cho, Hitachi City, Ibaraki Prefecture Within Rubber Processing Co., Ltd. (72) Creator Ryuzo Onuki Hitachi, 3-1-1 Sukegawa-cho, Hitachi City, Ibaraki Prefecture Within Rubber Processing Co., Ltd.

Claims (1)

[Scope of utility model registration request] Claim 1: A bushing for a transformer that is attached to a transformer case and is provided with a terminal for connecting an external lead wire and an internal transformer lead wire, wherein the bushing is connected to a transformer on the surface side of the bushing. an insulating cover of a predetermined thickness made of heat-resistant and oil-resistant insulating material for a part that enters the inside of the box and a part of the flange part that comes out of the box, and the terminal;
The heat-resistant and weather-resistant insulating material injected during this time is integrally formed, and this integrated insulating molded product is packed between the flange portion of the insulating cover that protrudes outside the box and the box. A bushing for a transformer, characterized in that the bushing is tightened and fixed to the case through the bushing.