JPH0442895Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Field of Industrial Application) The present invention relates to a coil for a molded transformer, and particularly relates to an improvement of the main insulator.

(Prior art) The coil of a three-molded transformer, which is generally molded from synthetic resin, is synthesized by providing a main insulator formed by overlapping or continuously winding a certain number of thin sheets of insulating material between the high-voltage coil and the low-voltage coil. It was cast in one piece using resin.

However, in such a configuration, especially when cast with a high viscosity synthetic resin, such as a synthetic resin containing a filler, it is difficult for the synthetic resin to impregnate between the high voltage coil and the main insulator or between the low voltage coil and the main insulator. Bubbles may remain in this portion, and in this case, there are drawbacks such as deterioration of partial discharge characteristics.

As a method to solve the above-mentioned drawbacks, corrugated insulation spacing plates are interposed on both the outer and inner peripheries of the main insulator, which is made by stacking or continuously winding a certain number of thin sheets of insulating material between the high-voltage coil and the low-voltage coil. This creates a constant gap between the high-voltage coil and the main insulator and between the low-voltage coil and the main insulator, making it easy to impregnate this area and prevent air bubbles even when casting high-viscosity synthetic resin. Coil configurations are being considered that do not leave any residue.

(Problem to be solved by the invention) However, in the above-described coil configuration, since the main insulator 3 meanders along the wave surface of the corrugated insulation spacing plate inserted on the inner circumferential side, the sheet of thin insulation material A void is generated in the main insulator layer formed by laminating the main insulator. When casting with high viscosity synthetic resin, the synthetic resin is difficult to impregnate into the voids generated in the main insulating layer, forming air bubbles, etc., reducing partial discharge characteristics, and eventually damaging the insulation. This is undesirable as it leads to destruction.

The present invention solves the above problems and provides a coil for a molded transformer that eliminates the unimpregnated portion of synthetic resin, eliminates the formation of bubbles, and improves partial discharge characteristics and dielectric breakdown characteristics. purpose.

[Structure of the invention] (Means for solving the problems) The coil of the molded transformer according to the invention has a main insulator formed by winding and laminating sheets of thin insulating material between a high voltage coil and a low voltage coil. In a coil configuration in which corrugated insulation spacing plates are interposed on both the inner and outer circumferential sides of the coil, a plate-shaped insulating plate is inserted between the main insulator and the corrugated insulation spacing plate inserted on the inner circumference side of the main insulator. It is something.

(Function) The plate-shaped insulating plate prevents the main insulator from waving and meandering along the wave surface of the corrugated insulating spacing plate inserted on the inner circumferential side.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

Fig. 1 is a sectional view showing a coil of a molded transformer according to the present invention, Fig. 2 is a sectional view of a main part taken along the - line in Fig. 1, and Fig. 3 is a main part of the main insulator shown in Fig. 1. FIG.

A corrugated insulating spacing plate 2a is applied to the outer peripheral surface of the low-voltage coil 1 over the entire circumference of the low-voltage coil 1, and a plate-shaped insulating plate 3 is applied thereon over the entire circumference. Furthermore, a sheet of thin insulating material is wound and laminated thereon to form the main insulator 4. A corrugated insulation spacing plate 2b is applied all around the outer circumference of the main insulator 4, and a high-voltage coil 5 is wound thereon to form a coil body, and this coil body is made of synthetic resin 6, etc. to obtain a molded transformer coil.

In the coil of the molded transformer constructed in this manner, as shown in FIG. Since the main insulator 4 is uniformly wound and laminated over the entire outer circumferential surface, no voids are generated in the laminated portion of the main insulator 4, and when the synthetic resin 6 is cast, the resin is not impregnated and air bubbles etc. There will be no remaining. Therefore, partial discharge does not occur, and partial discharge characteristics and dielectric breakdown characteristics are improved.

[Effects of the invention] As described above, according to the invention, the main insulator formed by winding and layering a sheet of thin insulation material inserted between the high-voltage coil and the low-voltage coil is uniformly laminated, and the high-viscosity synthetic resin When molded, no voids are created where the resin is not impregnated, and no air bubbles remain, so it is possible to obtain a molded transformer coil with good partial discharge characteristics and dielectric breakdown characteristics.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a coil of a molded transformer of the present invention, FIG. 2 is a sectional view taken along the line -- in FIG. DESCRIPTION OF SYMBOLS 1...Low voltage coil, 2a, 2b...Corrugated insulation spacing plate, 3...Plat-shaped insulating plate, 4...Main insulator, 5...
...High voltage coil, 6...Synthetic resin.

Claims (1)

[Scope of utility model registration request] A coil body consisting of a main insulator made by winding and laminating sheets of thin insulating material between a high-voltage coil and a low-voltage coil, and corrugated insulating spacing plates arranged on both sides of the inner and outer peripheries of this main insulator. A molded transformer coil integrally cast with synthetic resin, characterized in that a plate-shaped insulating plate is interposed between the main insulator and a corrugated insulating spacing plate provided on the inner peripheral surface of the main insulator. Molded transformer coil.