JPS5891612A - Manufacture of resin molded coil - Google Patents

Abstract

PURPOSE:To manufacture the resin molded coil having no fear of leakage of resin irrelevant to weight and volume of the coil by a method wherein the lower end face of the coil is supported by a plate part of hanger, and moreover a material of the same quality with the adhering face is used as the leakage preventing seal. CONSTITUTION:A conductor is wound around a cylindrical spool 1' consisting of a material having a large coefficient of thermal expansion to form the coil 2, and an outside circumferential insulating layer 3 is applied to the outside circumferential surface thereof. The coil 2 thereof is heated in a drying furnace to make the spool 1' to expand, and to enlarge the inside diameter of the coil 2, while the lower end face of the coil 2 is provided on the plate part 603 of the hanger 6 consisting of a rod part 602 to be inserted in a hollow part of the spool 1' and the plate part 603 interposing a cushion material 7 and a sheet material 8 between them. Then after the coil 7 is cooled to form a gap between the inside circumferential face thereof and the outside circumferential face of the spool 1', a cover 9 is tightened to the spool 1' by a tightening tool. After then, the leakage preventing seal is applied between the outside circumferential insulating layer 3 and the sheet material 8 mentioned above, and resin is impregnated from the upper end face of the coil 2 and the gap.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a resin molded coil, and particularly relates to a method of manufacturing a resin molded coil in which the resin molded coil is impregnated with a resin composition without using a mold. It is something.

Conventionally, the method of manufacturing resin molded coils used in dry type transformers, etc. is to place the bare coil in a mold, pour a resin composition such as epoxy resin into the surrounding area and inside the bare coil, and then harden it. It is used. However, this conventional manufacturing method has the disadvantage that it requires a large amount of labor and expense for mold release, assembly, disassembly after resin hardening, and maintenance of the row number ζ molds. Ta. For this reason, in an attempt to obtain a coil that does not use a mold and has the same performance as a coil manufactured using a manufacturing method that uses a mold, conventional methods such as those shown in Figure 1 have been used. □Eh.

FIG. 1 is a partial side view showing a conventional method of manufacturing a resin molded coil. As shown in FIG. 1, the winding core (1) is made of synthetic resin having a large coefficient of thermal expansion and has a cylindrical shape. The coil (2) is constructed by alternately winding a conductor and a base material around the core (1).

The outer peripheral insulating layer (3) is formed by winding a nonwoven fabric, such as aromatic polyamide, with poor impregnability around the outer periphery of the coil (2),
Moreover, the width is wider than the width of the coil (2). The end face seal (4) is constructed by applying a putty-like resin made of an epoxy resin mixture to the lower end face of the coil (2) and then hardening it in a drying oven. Leakproof seal (5)
A seal is used to close the gap between the winding core (1) and the coil (2), and a silicone adhesive, for example, is applied to the winding core (1) and the end face seal (
4) It is formed by coating between.

Next, the manufacturing and usage method shown in FIG. 1 will be explained. First, a coil (2) is constructed by alternately winding a conductor and a base material around a core (1) made of synthetic resin with a large coefficient of thermal expansion.
An aromatic polyamide nonwoven fabric having poor impregnability, for example, is wound around the outer periphery of the coil (2) to a width wider than that of the coil (2), and the end portion of the winding is sealed to form an outer peripheral insulating layer (3). Next, a putty-like resin made of a mixture of epoxy resin is applied to the lower end surface of the coil (2) and cured in a drying oven to seal (
4) Form. At this time, the winding core (1) expands due to thermal expansion, expanding the inner diameter of the coil (2). Next, this is cooled to create a gap between the outer circumferential surface of the winding core (1) and the inner circumferential surface of the coil (2), and the lower end surface of this gap is bonded with, for example, silicone adhesive. to form a leakproof seal (5). The winding core (1) expands in the drying oven and expands the inner diameter of the coil (2), and as it returns to room temperature, it contracts and becomes the first winding core (
A gap is created between the outer peripheral surface of coil (1) and the inner peripheral surface of coil (2). In this case, since the leakproof seal (5) is made of highly elastic rubber, it follows the contraction of the winding core (1) and maintains its sealing effect. The winding core (1) and coil (2) configured in this way are installed in a resin layer (not shown) so as not to damage the leak-proof seal (5), and the upper end surface of the coil (2) is From the side, apply an insulating resin for impregnation including an ultraviolet curable resin to the core (1), the outer insulating layer (3), and the end seal (4).
and a leak-proof seal (5) to impregnate it under pressure. After this pressure impregnation, the winding core (1) and the coil (2) are taken out from inside the resin layer (not shown), and the coil outer insulating layer (31) is irradiated with ultraviolet rays from an ultraviolet irradiation device (not shown). The surface of the insulating layer (3) is hardened. This is placed in a drying oven and heated to harden to complete the molded coil. Note that the outer peripheral surface of the winding core (1) and the coil (
2) The reason for creating a gap ^ between the core (1) and the inner circumferential surface is to expand the coil (2) by expanding the core (1) and increase the density inside the coil (2), and to increase the density inside the coil (2). The objective is to shorten the impregnation time by impregnating the resin from the gaps during impregnation.

However, when a coil is manufactured by the conventional method as described above, when a gap A is generated between the winding core (1) and the coil (2), the coil is attached to the leak-proof seal (5). Due to the overlapping of (2), a tensile force is exerted, and the adhesive force on the core (1) side is weak, which may cause peeling or resin leakage due to damage. In addition, when manufacturing a large coil using the same method, the weight of the coil (2) cannot be supported by the leak-proof seal (5) alone, resulting in resin leakage or the coil (2) tJL winding core (1). There was a drawback that it fell off.

This invention eliminates the drawbacks of the above-mentioned conventional ones, and the coil (2
) It is an object of the present invention to provide a method for manufacturing a resin molded coil without using a mold and without fear of resin leakage, regardless of the weight and size of the coil. An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a side sectional view showing an embodiment of the method for manufacturing a resin molded coil according to the present invention.

In the figure, the same parts as in FIG. 1 are given the same reference numerals. In FIG. 2, the winding core (1') is made of a synthetic resin having a large coefficient of thermal expansion and has a cylindrical shape.

The hanging tool (6) is made of metal, and includes a rod part (602) that is inserted through the hollow part of the winding core (1') and has a threaded part (601) at one end on the upper end surface side of the coil (2); The central part is attached to the other end of the rod part (602) and the coil (2
) and a plate portion (603) that supports the lower end surface of the coil (603) and has a diameter larger than the diameter of the coil (2). The cushioning material (7) is made of, for example, RL silicone rubber, and is installed between the plate portion (803) and the lower end surface of the coil (2). The sheet material (8) is made of, for example, the same material as the outer peripheral insulating layer (3) or a material with good adhesive properties, and after applying a release agent on the surface of the cushion material (7), it is The lid (9) is installed between the lower end surfaces of the coil (2).The lid (9) has an outer diameter comparable to that of the winding core (1'), and has a rod part (602)' in its center. A through hole (901) is inserted through the hole, and one or more ventilation holes (902) are provided near the center of the hole.The eye nut (10) is screwed into the threaded portion (601). , Itabe (
603), lid (9), and tension material (7)
The winding core (II) is tightened and fixed through the plate portion (803), and the lower end surface of the coil (2) is supported through the plate portion (803). The leak-proof seal (5-) is made of, for example, a fast-curing epoxy adhesive and is applied to close the gap between the outer peripheral insulating layer (3) and the sheet material (8).

Next, this manufacturing method will be explained. First, a coil (2) is constructed by alternately winding a conductor and a base material around a winding core (one core), and then a coil (2) of an impregnating impression 1 (for example, an aromatic polyamide nonwoven fabric) that is wider than the coil (2) is formed. The coil (2) is wound around the outer peripheral surface of the coil (2) so as to be aligned with the lower end surface of the coil (2), and the winding end portion is sealed to form an outer peripheral insulating layer (3).

Next, this is heated in a drying oven to expand the core (1') and enlarge the inner diameter of the coil (2). Next, place the cushioning material (7) on the plate part (603) of the hanging tool (6), and
After applying the bm agent to the top surface of the cushion material (7), the sheet material (8) is placed, and the rod portion (602) is inserted through the hollow portion of the cylindrical winding core (II) to close the coil (2). ) to the board (
603). Next, after the winding core (1') and the coil (2) have cooled down, the lid (9) is installed on the upper end surface of the coil (2), and the eye nut (10) is attached to the threaded part (601) of the winding core (II). ) is tightened to the extent that it does not move. In this case, since the lid (9) is provided with a ventilation hole (90'2), it can be easily tightened. Also, at this time, a gap A is generated between the inner circumferential surface of the coil (2) and the outer circumferential surface of the winding core (1'). Since the coil (2) may shift due to the generation of this gap, the position of the coil (2) is adjusted so that the gap A force f is uniform over the entire circumference, and a leak-proof seal (5I) is applied. In this case, use the leak-proof seal (5') K, the adhesive 4 to be used, and the winding core (1').
), there is no need for a rubber-like adhesive as in the conventional example, and a fast-curing epoxy adhesive is used. The winding core (1') and coil (2) constructed in this manner are impregnated with resin in the same manner as explained in the conventional example, and after hardening the surface of the coil (2) by ultraviolet curing, The molded coil is completed by heating and curing in a drying oven.

This invention is configured as described above, and even if the coil (2) becomes larger and heavier, the plate portion (603) of the hanging device (6)
Since the lower end surface of the coil (2) is supported by
This improves work efficiency such as transportation and improves safety. In addition, epoxy adhesive is used as a leak-proof seal (5').
The adhesive surface, that is, the outer peripheral insulating layer (3) and the sheet material (8)
Since the materials are the same, adhesiveness is improved. Furthermore, the coil (2) has a plate portion (6) having a larger diameter than the diameter of the coil (2).
03), so there is no risk of damage (and the resin will not leak from the outer periphery of the coil (2).Furthermore, the winding core (1') is made into a cylindrical shape. A lightweight, inexpensive, and highly reliable resin molded coil can be obtained.

In addition, by making the winding core (1') cylindrical, the winding core (1') is shaped like a cylinder.
1'), but the 1st roll core (1') is fastened to the plate part (603) with an eye nut (10) via the cushion material (7) right side and the sheet material (8). Therefore, no resin flows into the core (1') during impregnation. Furthermore, as the core (1') expands in the axial direction due to heating during curing, the clamping force further increases. ) There is no risk of it flowing into the interior. Furthermore,
The present invention is not limited solely to the method of moxibustion of transformer coils.

, m1o*'5"c"*"A"0°i, mm1
Even a large coil can be manufactured without worrying about ATVV, and it has the effect of obtaining an inexpensive and highly reliable resin molded coil.

[Brief explanation of drawings]

FIG. 1 is a partial side sectional view showing a conventional method for manufacturing a resin molded coil, and FIG. 2 is a side sectional view showing an embodiment of the method for manufacturing a resin molded coil according to the present invention. In the diagram, (II) is the winding core, (2) is the coil, (3)
is the outer insulating layer, (5') is the leak-proof seal, (6) is the hanging ^, (601) is the screw part, (602) is the rod part, (6
03) is a plate part, (7) is a cushion material, (8) is a sheet material, (9) is a lid, (901) is a through hole, (902) is a ventilation hole, and (10) is an eye nut. Identical parts and equivalent parts in each figure are marked with the same numerals and a dash is added to the same numerals. I Procedural Amendment (Voluntary) May-April 5, 1939 Mr. Commissioner of the Patent Office 1, Indication of Case Patent No. 1il 1986-190222
No. 2, Name of the invention Method for manufacturing a resin cold coil 3, Person making the amendment 5, Detailed description of the invention in the specification subject to amendment 6, Contents of the amendment (1) Part 5 of the specification, page 15 line and page 6, line 1: “
The words ``resin layer'' are corrected to ``impregnation tank.'' (2) On the same page 5, line 17 to line 1g, line 19, “, core (1)
``In a tank composed of 11 and 11'' is deleted. that's all

Claims (1)

[Claims] 1. A first step of forming a coil by winding a conductor around a cylindrical winding core made of a material with a large coefficient of thermal expansion, and a second step of forming an outer peripheral insulating layer on the outer peripheral surface of the coil. step, the coil is heated in a drying oven to expand the core and increase the inner diameter of the coil; The plate part number ζ of the hanging device is composed of a plate part whose central part is attached to the other end of the rod part, and the plate part number ζ is attached to the bottom of the coil through a cushion material and a sheet material applied on the surface of the cushion material. A third step of installing an end face, after cooling the coil and forming a gap between the inner circumferential surface of the coil and the outer circumferential surface of the winding core. a fourth step of tightening a lid installed on the upper end surface of the winding core to the winding core with a fastener screwed into the threaded portion; a sixth step of applying a leak-proof seal between the outer peripheral insulating layer and the sheet material; A method for producing a resin-molded coil, comprising the following steps: a step and a sixth step of impregnating resin from the upper end surface of the coil and the gap. 2. The method of manufacturing a resin molded coil according to claim 1, wherein a through hole is provided in the center of the lid for inserting the rod portion therethrough, and a ventilation hole is provided in the lid. The method for manufacturing a resin molded coil according to claim 1, wherein the outer peripheral insulating layer and the sheet material are made of the same material. 4. The method for manufacturing a resin molded coil according to claim 1, wherein the leak-proof seal is applied with a fast-curing epoxy adhesive. 5. Release the sheet material onto the surface of the cushioning material II &
A method for manufacturing a resin molded coil according to claim 1, which is performed after the resin molding is performed. 6. The method for manufacturing a resin molded coil according to claim 1, wherein the diameter of the plate portion of the hanging tool is larger than the diameter of the coil.