CN210200463U

CN210200463U - Voltage transformer

Info

Publication number: CN210200463U
Application number: CN201921481100.5U
Authority: CN
Inventors: Junfeng Lou; 娄军峰; Qianya Yuan; 袁钤亚; Junchao Liu; 刘军超; Qunchao Xie; 谢群超; Weiwei Chen; 陈伟伟
Original assignee: Henan Senyuan Electric Co Ltd
Current assignee: Henan Senyuan Electric Co Ltd
Priority date: 2019-09-06
Filing date: 2019-09-06
Publication date: 2020-03-27
Anticipated expiration: 2029-09-06

Abstract

The utility model relates to a voltage transformer. The voltage transformer comprises an insulator and a transformer body; the insulator comprises an outer insulating shell and a silicon rubber insulator; the outer insulating shell is provided with a glue injection port for injecting liquid silicon rubber; the silicon rubber insulator is formed in the inner cavity of the outer insulating shell and is formed by solidifying liquid silicon rubber. By adopting the scheme, the manufacturing efficiency is high, and the production cost is low.

Description

Voltage transformer

Technical Field

The utility model relates to a voltage transformer.

Background

The voltage transformer is an electrical component widely used, for example, one of main mating electrical components of a pole-mounted circuit breaker, and has a structure as shown in fig. 1 and chinese patent document No. CN207938456U, publication No. 2018.10.02, and includes a body, an inner insulator, and an outer insulator (the outer insulator is not shown in fig. 1). The main body of the transformer body is formed by an iron core 92, a primary winding 93 and a secondary winding 94, the iron core 92 penetrates through the secondary winding 94, the primary winding 93 is located on the radial outer side of the secondary winding 94, the primary winding 93 is connected with a primary winding insert 95, and the secondary winding 94 is connected with a secondary lead insert 96. The inner insulator 97 is molded by casting epoxy resin, the transformer fixing insert 91 is arranged at the top of the corresponding casting mold, and the transformer fixing insert 91 is fixed in the inner insulator after molding for realizing the installation of the voltage transformer. The outer insulator is formed of silicon rubber and is coated on the inner insulator 97 after it is molded. For some pole-mounted circuit breakers, the voltage transformer also includes a fuse mounting cavity 98, with the primary winding insert of the voltage transformer disposed in the fuse mounting cavity 98 for connection of the fuse.

At present, the production method of the product mostly adopts an injection molding or vacuum casting molding production method, and the vacuum casting method is applied more frequently. The vacuum casting method comprises the following steps: after the transformer body is wound, assembling the transformer body into a mold cavity through positioning tools such as a supporting piece and a hoisting piece, injecting epoxy resin into the mold cavity through vacuum casting equipment, then curing and molding at high temperature, demolding, and then re-curing the product for the second time; after all the flows are finished, the outer part is sleeved with a silica gel sleeve. In the casting process, the epoxy resin forms a primary insulation between the primary winding and the secondary winding.

According to the production method, manual adjustment is needed during assembly of the transformer body, so that quality problems of product partial discharge exceeding standard, insulation breakdown, coil leakage and the like caused by the problems of non-centering adjustment or non-in-place assembly of coils (secondary windings or primary windings) are avoided, and the adjustment time is long. In addition, in the molding process of the product, the shortest molding time is 6-8 hours, the secondary curing is also 10 hours, and in addition, the device body assembly, the mold pre-baking, the casting body cooling, the appearance polishing and the like are added, the molding time of a single product is about 40 hours, and the product needs to occupy the mold in most of the time. Therefore, the overall manufacturing efficiency is low, the increasing demands of the market are difficult to meet, the labor intensity of staff is high, and the energy consumption of equipment is high. And the productivity is increased by increasing the number of the casting molds, so that extra burden is added to enterprises, and certain waste is caused to social resources.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a voltage transformer, its structure is convenient for make, is favorable to improving manufacturing efficiency.

The utility model discloses technical scheme as follows that well voltage transformer adopted.

The voltage transformer comprises an insulator and a transformer body;

the insulator comprises an outer insulating shell and a silicon rubber insulator;

the outer insulating shell is provided with a glue injection port for injecting liquid silicon rubber;

the silicon rubber insulator is formed in the inner cavity of the outer insulating shell and is formed by solidifying liquid silicon rubber; the body is cast in a silicone rubber insulator.

Has the advantages that: the outer insulating shell of the voltage transformer is made of epoxy resin, is small in thickness and high in curing speed, and can be formed separately for later use; and when the ware body was assembled, the outer insulating casing that epoxy made can form the die cavity that supplies liquid silicon rubber casting moulding, compares with prior art, and during the manufacturing, liquid silicon rubber curing process need not occupy the mould for a long time to be favorable to improving the mould utilization ratio, and then improve manufacturing efficiency, reduce time cost, simultaneously, improve the mould utilization ratio and also be favorable to reducing mould quantity, thereby reduce equipment cost.

As a preferred technical scheme, the glue injection port of the outer insulating shell is an opening corresponding to the bottom surface of the voltage transformer.

Has the advantages that: the bottom surface area of the voltage transformer is large, and the voltage transformer is favorable for installation and glue injection of the transformer body.

As a preferable technical solution, an insulating support is arranged between the primary winding and the secondary winding of the body, and the insulating support is used for keeping the primary winding and the secondary winding relatively fixed.

Has the advantages that: the relative position between primary winding and the secondary winding can be guaranteed to insulation support between primary winding and the secondary winding, and during manufacturing, primary winding and secondary winding can go on alone, need not adjust temporarily when the pouring to can save the adjustment time, further improve manufacturing efficiency, guarantee product quality.

In a preferred embodiment, the insulating support is formed of an insulating frame and an electrostatic shielding layer fixed to the outer side of the outer peripheral surface of the insulating frame.

Has the advantages that: the electrostatic shielding layer arranged on the insulating framework can conveniently realize electrostatic shielding and conveniently ensure the electrical performance of the product.

Drawings

FIG. 1 is a schematic diagram of a prior art process for forming a voltage transformer;

fig. 2 is a schematic diagram of a forming process of the medium voltage transformer of the present invention, and is also a schematic diagram of an internal structure of an embodiment of the medium voltage transformer of the present invention;

FIG. 3 is a schematic diagram of the structure of the insulating frame and shield of FIG. 2;

fig. 4 is a schematic external view of the completed voltage transformer.

The names of the components corresponding to the corresponding reference numerals in the drawings are: 1. the transformer comprises a transformer fixing insert, 2, an iron core, 3, a primary winding, 4, a secondary winding, 5, a primary winding insert, 6, a secondary lead insert, 8, an insulating framework, 9, a silicon rubber insulator, 10, an electrostatic screen, 11, an outer insulating shell, 12, a silicon rubber outer sleeve, 13 and a fuse mounting cavity.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

The utility model discloses an embodiment of well voltage transformer, as shown in fig. 2, fig. 3 and fig. 4, including insulator and ware body, the insulator includes outer insulating shell 11 and silicon rubber insulator 9, silicon rubber insulator 9 shaping is by the solidification shaping of liquid silicon rubber in the inner chamber of outer insulating shell, the ware body solidifies in silicon rubber insulator. An opening of the outer insulating shell 11 corresponding to the bottom surface of the voltage transformer is a glue injection port, the glue injection port is used for injecting liquid silicon rubber, and the liquid silicon rubber is solidified to form the silicon rubber insulator 9.

The body of the voltage transformer comprises a primary winding 3, a secondary winding 4 and an insulating support. The insulating support is used for keeping the primary winding and the secondary winding relatively fixed, and comprises an insulating framework 8, wherein the surface of the insulating framework 8 is provided with a semiconductor crepe paper for shielding treatment, and meanwhile, as shown in fig. 3, a copper foil is pasted on the outer peripheral surface to be used as an electrostatic shielding layer 10.

The manufacturing method of the voltage transformer comprises a transformer body winding step, an outer layer insulation shell forming step, a silicon rubber pouring step, a silicon rubber curing step and an outer insulator mounting step, wherein the transformer body winding step, the outer layer insulation shell forming step, the silicon rubber pouring step, the silicon rubber curing step and the outer insulator mounting step are included.

A step of winding the transformer body: as shown in fig. 2, an insulating framework 8 which is prepared in advance is sleeved on the secondary winding 4 to be used as main insulation between the primary winding 3 and the secondary winding 4, semiconductor crepe paper is arranged on the surface of the insulating framework 8 to carry out shielding treatment, meanwhile, as shown in fig. 3, copper foil is pasted on the outer peripheral surface to be used as an electrostatic shielding layer 10 to form an insulating support, the primary winding 3 is wound outside the insulating support, and the formed primary winding is used for standby. Wherein the iron core 2 of the transformer body is of a split structure and can penetrate into the secondary winding 4. In this embodiment, the insulating frame is formed by vacuum casting using 9001F epoxy resin mixture in the prior art. In other embodiments, other insulating materials can be used, such as 9276 epoxy resin compound in the prior art, and the molding method can also be APG static pressure injection molding.

Forming an outer insulating shell: the outer insulating shell 11 is a shell with the wall thickness of 8mm, is molded by adopting an APG (automatic pressure forming) pressure molding process, is made of flame-retardant epoxy resin 7 used in the integral casting molding in the prior art, is about 35min in the molding process, and can be placed for standby after being produced according to the market order condition.

During molding, a fuse mounting and dismounting opening is reserved at a fuse mounting position, namely an opening at the position of the lowest (according to the direction of the drawing) end of the voltage transformer in fig. 2 for mounting and dismounting the fuse, a corresponding cylindrical mold is inserted into the opening, and liquid silicon rubber can enter between the cylindrical mold and the outer insulating shell 11 during pouring.

Of course, in other embodiments, the wall thickness of the outer insulating shell 11 may be increased or decreased as required, and the wall thickness should meet the insulation requirement and the structural strength requirement of the corresponding voltage class, which can be designed as required by those skilled in the art without creative work. The outer insulating shell 11 is formed by an APG pressure forming process, which has a short forming time, a high production efficiency and a low labor intensity, and in other embodiments, the outer insulating shell 11 may be formed by other forming processes, such as vacuum casting.

Pouring silicone rubber: placing the outer-layer insulating shell 11 in a mode that the bottom opening faces upwards, inserting the wound transformer body into the prepared product shell, enabling the transformer body to be in contact with the inner wall of the top shell on the outer-layer insulating shell 11, and positioning the transformer body by using a positioning tool; then, fixing a primary winding insert 5, installing a die in a dismounting opening of the fuse, forming an annular space between the die and the inner wall of the outer insulating shell, connecting a secondary coil with a secondary lead insert 6, pouring prepared liquid silicon rubber, finally keeping the transformer fixing insert 1 at a fixed position through a corresponding insert positioning tool, and removing the insert positioning tool after the silicon rubber is cured. In this process, the relative positions of the primary winding 3 and the secondary winding 4 do not need to be adjusted.

Curing the silicon rubber: curing at normal temperature, and standing for curing. The silicone rubber adopted in the embodiment is self-adhesive silicone rubber GMX-6117 and a corresponding vulcanizing agent in the prior art, the two components form bi-component silicone rubber, the bi-component silicone rubber is uniformly mixed and stirred, the mixture is poured into a mold cavity, and the curing and molding can be carried out at normal temperature for 3-4 hours.

An outer insulator mounting step: after the curing is completed, the silica gel outer sleeve 12 is sleeved outside the product according to the process requirements, as shown in fig. 4, and the manufacture of the voltage transformer is completed.

By adopting the manufacturing method of the voltage transformer, the whole production process can be controlled to about 4h from installation and molding.

In the above embodiment, the voltage transformer is a voltage transformer with a fuse, and the primary winding insert 5 for connecting with the fuse needs to be provided, in other embodiments, the voltage transformer without the fuse may also adopt the above insulator structure, and the corresponding primary winding insert 5 is used for primary wiring of the voltage transformer.

In the above embodiment, the glue injection port corresponds to the bottom opening of the outer insulating shell 11, and the liquid silicone rubber is injected from the bottom opening of the outer insulating shell 11 during manufacturing; in other embodiments, the glue injection port may also be disposed at other positions, for example, a position corresponding to a side surface or a top surface of the voltage transformer.

In the above embodiments, the liquid silicone rubber is a normal temperature curing type liquid silicone rubber, that is, a liquid silicone rubber capable of being cured and molded at normal temperature, and in other embodiments, other forms of liquid silicone rubber, such as a liquid silicone rubber cured by heating in the prior art, may also be used. Of course, the curing time needs to be considered when selecting the liquid silicone rubber, so that the production efficiency is ensured.

Finally, it should be noted that the above mentioned embodiments are only preferred embodiments of the present invention, and not intended to limit the present invention, and although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made without inventive effort to the technical solutions described in the foregoing embodiments, or equivalents may be substituted for some of the technical features. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. Voltage transformer, including insulator and ware body, its characterized in that:

2. The voltage transformer of claim 1, wherein: the glue injection port of the outer insulating shell is an opening corresponding to the bottom surface of the voltage transformer.

3. The voltage transformer according to claim 1 or 2, characterized in that: and an insulating support is arranged between the primary winding and the secondary winding of the transformer body and used for keeping the primary winding and the secondary winding relatively fixed.

4. The voltage transformer of claim 3, wherein: the insulating support is formed by an insulating framework and an electrostatic shielding layer fixed on the outer side of the outer peripheral surface of the insulating framework.