JPH0322510A - Manufacturing method of resin molded coil - Google Patents

Abstract

PURPOSE:To contrive both miniaturization of a machine and reduction in the quantity of resin by a method wherein a semihardened sheet insulator is formed, an outside frame is attached to the outer circumference of the insulating layer, and casting resin is filled in the groove part to be formed. CONSTITUTION:After an inner circumference insulating material 2 has been wound and fixed to a bobbin 1, an interlayer insulating material 3 and a sheet-like conductor, on which a rising plate 3 is attached, are wound around together, the rising plate 3 is attached and fixed to the finishing end of winding of the sheet-like conductor, and a coil 4 is formed. Then, an outer circumferential insulating material 5 is wound on the outer circumference coil winding 4, a shaping frame 6 is attached to the outer circumference of the insulating material 5, the external form is shaped up, a shaping frame 6 is attached to the outer circumference of the insulating material 5, and the external form is shaped up. Then, the end face where a rising plate 3 is coming out is faced downward, molding resin is filled up on the upper end face, and after the resin has been hardened, the end face is reversed, molding resin is filled up and hardened on the end face of the other coil, and the resin is hardened. After the abovementioned processes have been finished, the shaping frame 6 and the bobbin 1 are removed, and the manufacture of the molded coil is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a resin molded coil.

Conventional technology The conventional method for manufacturing a molded coil is to arrange an insulating material on the inner and outer peripheral surfaces of a coil body made of an interlayer insulating material and a conductor, and then place the coil body in a mold and inject molding resin. There is a method of disposing an insulating material on the inner peripheral surface and outer peripheral surface of the coil body, and then filling the ends of the coil with molding resin.

A schematic cross-sectional view of a molded coil manufactured using the latter method is shown in FIG. 2, and a conventional method for manufacturing a molded coil will be explained based on it.

The inner circumferential insulating material 12 is wound around the winding core 11, and the interlayer insulating material 1
7 and the conductor 18 a predetermined number of times to form a coil body, an outer insulating material 19 is wound and fixed around the outer periphery, the upper end surface of the coil body is sealed, and the end portion is filled with molding resin. The coil body is then cured, turned over, and the other unfilled end face of the coil body is filled with molding resin and cured. As the inner circumferential insulating material 12 and the outer circumferential insulating material 19, a polyethylene terephthalate film or a polyethylene terephthalate nonwoven fabric or an aromatic polyamide nonwoven fabric bonded thereto is used. Furthermore, as mold resin,
Epoxy resins are widely used. 20 is a mold resin layer, and 21 is an outer peripheral mold resin layer.

In the conventional resin mold manufacturing method described above, ``After the first coil end mold resin is filled and hardened, it is reversed and the other coil end is filled with the second mold resin, and during the curing process, the coil outer periphery The resin also penetrates to form the outer peripheral mold resin layer 21.

Problems to be Solved by the Invention However, in the above conventional manufacturing method, after the second molding resin is filled into the end of the coil, a part of the molding resin invades the outer periphery of the coil during the curing process, resulting in an increase in the outer diameter. Moreover, the amount of mold resin used also increases. Also,
In the case of a conventional structure, peeling may occur at the interface between the inner and outer insulating materials 12.19 and the molded resin layer 20 during a thermal aging heat cycle test, so although it is sufficient in terms of reliability, do not have.

Means for Solving the Problems In order to solve the above problems, the method for manufacturing a resin molded coil of the present invention includes a first insulating layer formed by winding a semi-hardened sheet 1 insulator around a winding core. a second step of winding an interlayer insulating material and a conductor on the first insulating layer to form a coil body; and a third step of forming a semi-cured sheet-like insulating layer on the coil body. The fourth step is to attach an outer frame to the outer periphery and tighten the outer periphery. and a fifth step of filling a molding resin into the groove formed by the end face of the coil body and the first and second sheet-like insulating layers, and hardening the resin.
and a sixth step of removing the outer frame and the winding core at the outer periphery of the coil after the resin is cured.

Effects According to the method for manufacturing a resin molded coil described above, the mold resin is cured with the outer periphery tightened by the outer frame, so that there is no intrusion of the resin into the outer periphery. In addition, a semi-cured sheet insulator is used for at least the side of the inner circumferential material and the outer circumferential material of the coil that are in contact with the molding resin, and because it hardens with the curing of the molding resin, it is easy to form an integral structure.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1(a) is a schematic perspective view of a resin molded coil in a manufacturing process according to an embodiment of the present invention. FIG. 1(b) is a partially schematic sectional view showing a state in which both end faces of the coil body are filled with molding resin and hardened.

In the figure, after the inner insulating material 2 is wound and fixed around the winding core 1, the interlayer insulating material 7 and the sheet-like conductor to which the rising plate 3 is attached are wound together, and the rising plate 3 is placed at the end of the winding of the sheet-like conductor. are attached and fixed to form the coil body 4. Next, an outer periphery insulating material 5 is wound and attached to the outer periphery, and a shaping frame 6 is further attached to the outer periphery to shape the outer shape. Next, with the end surface where the rising plate 3 is exposed facing down, the upper end surface is filled with molding resin and cured, and then the coil is turned over and the other end surface of the coil is filled with molding resin and cured.

After the above steps are completed, the shaping frame 6 and the winding core 1 are removed to complete the production of the molded coil. The above-mentioned inner circumferential insulating material 2 is made by laminating a semi-cured epoxy resin-impregnated glass cloth and a polyester film so that the semi-cured epoxy resin-impregnated glass cloth is in contact with the molding resin for molding the coil end. Although other sheet-like materials are practical, the aforementioned materials are suitable when used in environments with severe heat cycling. Furthermore, as a mold resin, fillers such as quartz are added to the basic resin composition, which is made by adding reaction catalysts such as acid anhydride curing agents and tertiary amines to ordinary epoxy resin.
-70% by weight is used. However, when the end face of the coil that does not protrude from the riser plate 3 is molded with resin, a material containing several percent of colloidal silica or the like 5 6 to give thixotropic properties is used to prevent resin leakage. The shaping frame 6 may be made of an iron plate formed into the outer shape of the coil, or a rubber sheet or fer 1 etc. may be attached to the part facing the straight part of the coil so that sufficient pressure can be applied. is also possible.

Effects of the Invention As described above, in the present invention, since the resin is filled and hardened while being suppressed from the inner and outer peripheries of the coil, there is almost no resin intrusion into the outer periphery of the coil, improving dimensional accuracy and downsizing the equipment. will be realized. Moreover, the amount of resin is also reduced. Furthermore, by using glass cloth impregnated with semi-cured epoxy resin on at least the side of the inner and outer insulating materials in contact with the mold resin, and by using the epoxy resin as the mold resin, the mutual adhesion between them is improved and thermal aging is prevented. Withstands heat cycling and use under harsh cold and heat conditions.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view of a molded coil in the manufacturing process according to an embodiment of the present invention, FIG. 1(b) is a partially cutaway schematic sectional view of the molded coil, and FIG. 2 is a perspective view of the molded coil in the manufacturing process according to an embodiment of the present invention. It is a partially cutaway schematic sectional view of the molded coil in the middle of the manufacturing process. 1... Winding core, 2... Inner periphery insulating material, 4
... Coil body, 5 ... Outer insulating material,
6... Frame for shaping, 7... Interlayer insulation material, 8... Sheet-like conductor, 9... Molding resin layer.

Claims (2)

[Claims] (1) A first step of winding a semi-cured sheet insulator around a winding core to form a first insulating layer, and winding an interlayer insulating material and a conductor on the first insulating layer to form a coil body. a second step of forming a semi-cured sheet-like insulating film on the coil body; a fourth step of attaching an outer frame to the outer periphery of the coil body and tightening the outer periphery; a fifth step of filling and curing a casting resin into the groove portion formed by the end surface of the coil body and the first and second sheet-like insulating layers; A method for manufacturing a resin molded coil, comprising a sixth step of removing. (2) The method for manufacturing a resin molded coil according to claim (1), wherein the semi-cured sheet insulator is a porous material impregnated with a semi-cured epoxy resin, and the casting resin is an epoxy resin.