JPS6257207A - Molded coil - Google Patents

Abstract

PURPOSE:To provide an inexpensive molded coil without using a winding mold, a coil supporter and the like, by filling a putty-form resin in an annular groove, which is formed with thin-leaf insulators that are broader than a coil wound around a laminated iron core, and hardening the resin. CONSTITUTION:A prepreg tape 2a, which is the first thin-leaf insulator, is wound around the straight part of a laminated iron core 5 so that the width of the insulator is broader than the height of a coil 1. A prepreg tape 2b, which is the second thin-leaf insulator, is wound around the outer surface of the coil that is wound several times on the prepreg tape 2a so that the tape 2b is broader than the height of coil 1. An annular groove part 1a between the prepregs 2a and 2b wound around the inner and outer surfaces of the coil 1 at both ends surfaces of the coil 1 is filled with a putty shaped resin. The resin is hardened. Thus an inexpensive molded coil, which does not require a coil former, a coil supporter and the like, can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a coil for a resin molded transformer, and particularly to a coil structure suitable for manufacturing at low cost without using a mold.

Background of the invention] The coil of a conventional molded transformer is disclosed in Japanese Patent Application Laid-Open No. 57-1212.
07, as shown in FIGS. 5 and 6, the winding form 10. 7. After winding the prepreg 2 around the flange 11 and winding a coil thereon, the prepreg is wrapped around the outer layer via the spacer 3. After that, the flange 11 and the prepreg are sealed 12, and the liquid resin 7 is poured through the upper part. 1, and hardened to obtain a cylindrical molded coil as shown in FIG. This structure requires a mold during manufacturing, and since it is cylindrical, when combined with an iron core as shown in Figure 8, parts such as a coil support 4 are required to hold the iron core and coil. There was a problem in that it was expensive, but in the past, as mentioned above, a winding form and 7 lunges were required, so a mold had to be made for each model, and the mold cost was high. In addition to this, in the case of products with very short delivery times, a slightly larger mold was used when the mold was not available in time, resulting in material being wasted.

[Purpose of the invention]

An object of the present invention is to provide an inexpensive molded coil that does not require a winding form or coil support during manufacturing.

[Summary of the invention]

The present invention provides a molded coil including a first thin-sheet insulator wound around a laminated iron core, a coil wound on the first thin-sheet insulator, and a second thin-sheet insulator wound around the outer periphery of the coil. the second thin-film insulator and the first thin-film insulator are wound around the outer periphery of the coil and the outer periphery of the iron core, respectively, so as to have a width wider than the height of the coil; It is characterized in that a putty-like resin is filled in an annular groove formed between both end faces and the first thin insulator and the second thin insulator and then hardened.

[Embodiments of the invention]

Embodiments of the present invention will be explained below using FIGS. 1 to 4.

In the molded coil of this embodiment, as shown in FIGS. 1 and 2, a prepreg tape 2a, which is a first thin insulator, is wound around the linear part of the laminated iron core 5 to a width wider than the height of the coil 1. , prepreg tape 3. Wrap the prepreg tape 2b, which is a second thin insulator, to a width wider than the height of the coil 1, and wrap the coil 1 on both end surfaces of the coil 1.
A putty-like resin 8 is filled in an annular groove 1a formed between prepregs 2a and 2b wound around the inner and outer peripheries of the prepreg 8, and then hardened. Note that the prepregs 2a and 2b are not limited to tape shapes, but may be sheet-shaped with a width wider than the height of the coil 1 to reduce the number of winding steps. The method for manufacturing the molded coil of this example will be described below. do.

An iron core 5 made of laminated silicon steel plates cut into short bars is chucked into a winding machine (not shown), and a prepreg tape 2a made of glass or polyester tape coated with semi-cure resin is placed on top of the iron core from the height of the coil 1. The coil 1 is formed by winding the coil conductor a predetermined number of times. Thereafter, the prepreg tape 2b is wrapped around the outer peripheral surface of the coil 1 in the same manner as the lower layer, and the iron core 5 is removed from the winding. 10 to 15 protruding from one end face of the coil
Putty-like resin 8 is stuffed into the annular groove 1a formed between the prepregs of
Dry to remove moisture inside the coil and harden the resin. Next, the putty-like resin 8 is filled in the annular groove 1a on the other end face by turning it over and heating it at 100-150°C for 15-20 minutes.
The molded coil shown in FIG. 3 is obtained by curing and drying for 0 hours.

In this embodiment, the putty-like resin 8 was filled into the groove 1a and hardened on one side at a time, but it is also possible to fill and harden both sides at the same time to shorten the manufacturing time.

To manufacture a transformer using the molded coil of this embodiment, it is only necessary to manufacture other coils in the same manner, connect them to the upper and lower yoke cores 13, and attach the core clamping fittings 6. FIG. 4 is an example of a single-phase transformer using the molded coil of this embodiment.

According to this embodiment, a winding form for the coil is not required, the iron core and the coil are completed as a single unit, and coil supports and bolts and nuts for pressing the coil supports are also unnecessary, reducing the number of sheathing jigs and parts. I can do one thing. Alternatively, putty-like resin may be filled only on one end surface of the coil, and after curing and drying, the other end surface may be filled with liquid resin and cured.

〔Effect of the invention〕

According to the present invention, it is possible to obtain an inexpensive molded coil that does not require a winding form or a coil support.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a molded coil according to an embodiment of the present invention, FIG. 2 is a longitudinal sectional view of a molded coil according to an embodiment of the present invention, and FIG. 3 is a perspective view of a molded coil according to an embodiment of the present invention. 4 is a front view of a transformer using a molded coil according to an embodiment of the present invention, FIG. 5 is a longitudinal sectional view of a conventional molded coil, FIG. 6 is a plan view of a conventional molded coil, and FIG. FIG. 7 is a perspective view of a conventional molded coil, and FIG. 8 is a front view of a transformer using a conventional molded coil. DESCRIPTION OF SYMBOLS 1... Coil, 1a... Annular groove part, 2a... First thin sheet material, 2b... Second thin sheet insulator, 5... Iron core, 8$ 4 Concave 773

Claims (1)

[Claims] A first thin sheet insulator wound around a laminated iron core, a coil wound on the first thin sheet insulator, and a second thin sheet insulator wound around the outer periphery of the coil. The second thin sheet insulator and the first thin sheet insulator are wound around the outer periphery of the coil and the outer periphery of the iron core, respectively, so that the width thereof is wider than the height of the coil, and the second thin sheet insulator and the first thin sheet insulator are wound around the outer periphery of the coil and the outer periphery of the iron core, respectively. 1. A molded coil characterized in that a putty-like resin is filled into an annular groove formed between the thin-film insulator and the second thin-film insulator, and then hardened.