JPH03283413A - Iron core for stationary induction apparatus - Google Patents

Abstract

PURPOSE:To make it possible to easily insert a coil into a U-shaped iron core unnecessitating the cutting of thin and hard magnetic material by a method wherein continuously-wound magnetic material is formed into U-shape and I-shape without cutting the magnetic material sheet by sheet, and both ends of the I-shaped core are butt together to both open ends of the U-shaped core. CONSTITUTION:A magnetic material 3 is wound on a coil frame 5 from a spool 4 gradually, and a roundly-wound core 6 is formed. The roundly-wound core 6 is taken off from the coil frame 5, and after the roundly-wound core 6 has been inserted between a recessed mold 7 and a protruding mold 8, pressure is applied from above the protruding mold 8, and the roundly-wound core 6 becomes a U-shaped core 1. After the roundly-wound core 6 has been inserted between the upper press-plate 11 and the lower press-plate 12, pressure is applied from above the press-plate 11, and the roundly-wound core 6 becomes an I- shaped core 2. A U-shaped core 1, on which magnetic material 3 is continuously wound in U-shape, and an I-shaped core 2, on which a magnetic material 3 is continuously wound in I-shape, are butt-together in the direction where the laminated surfaces of both cores are brought into contact with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to an iron core for a stationary inductor such as a transformer using an amorphous magnetic material or a thin magnetic material having a thickness of 100 (μm) or less.

"Prior Art" An embodiment of a stationary inductor core using a conventional amorphous magnetic material or a monomagnetic material having a thickness of 100 (μm or less) will be described with reference to FIGS. 5 and 6.

FIG. 5(a) is a front view of the step lap cut type wound core. The step lap cut type wound core 13 is formed by winding the magnetic material 3, and the magnetic material 3 has a seam 14 at every turn. . FIG. 5(b) is an enlarged view of the seam 14, in which the position of the seam is sequentially moved in a stepwise manner in order to improve the magnetic properties.

Although not shown in the drawings, the step-lap cut type wound core is manufactured by (1) cutting the magnetic material one by one in varying lengths from the inside of the core to the outside; ■The cut surfaces of the cut magnetic material are shifted one by one and wound into a circular winding form. ■
Remove the circular former and insert the rectangular mold into the core.

■Annealing the iron core together with the mold. ■After annealing is complete, remove the mold.

It is done in this process.

Figure 6 is a front view and a side view of the stacked core.
5 is formed by stacking magnetic materials 3a and 3b of different sizes.

Although not shown in the figure, the production of this stacked iron core involves (1) cutting the magnetic material one by one; ■Annealing the cut magnetic material. ■Stack the magnetic materials one by one after annealing. It is done in this process.

``Problems to be Solved by the Invention'' In the case of a step lap cut type wound core as shown in Fig. 5, it is necessary to cut a thin, hard magnetic material at one point per turn, changing the length. Furthermore, since it is necessary to shift the cutting points of the cut magnetic material and wind it onto a winding form, cutting and shifting the thin and large number of magnetic materials requires a great deal of labor and expensive automatic cutting equipment. In addition, when inserting a coil (not shown) after the core is completed, the cutting point is opened once, so with materials that are extremely brittle after annealing, such as amorphous magnetic materials, the core may be damaged or the magnetic properties It often made things worse.

In the case of the stacked core shown in Figure 6, the number of cutting points per circumference of the core is 4.
It took a lot of effort to cut a very large number of pieces of magnetic material and stack them one by one. Additionally, the magnetic properties were also poor because there were four joints in the iron core.

"Means for Solving the Problem" In the present invention, without cutting the magnetic material one by one, continuously wound magnetic material is formed into a U-shape and a single-shape,
Both ends of the single-shaped core are brought into contact with the open ends of the U-shaped core to provide the core of the stationary inductor.

"Function" According to the present invention, an iron core for a stationary inductor can be obtained by continuously winding and molding a magnetic material. Further, an expensive automatic cutting device is not required, and the labor required for manufacturing is also reduced.

In addition, since the coil can be inserted into the core without opening the cut surface as in the case of a step-lap cut core, the core will not be damaged or the magnetic properties will not deteriorate.

Furthermore, there are only two joint surfaces of the iron core.

The magnetic properties do not deteriorate as with stacked iron cores.

"Embodiment" An embodiment of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a front view and a side view of the iron core of the present invention, showing a U-shaped iron core 1 in which magnetic material 3 is continuously wound in a U-shape, and a ■-shaped iron core in which magnetic material 3 is continuously wound in a 1-shape. 2 are butted against each other in the direction in which the laminated surfaces of both cores are in contact with each other.

FIG. 2 shows another embodiment of the iron core of the present invention, showing a front view and a side view.
, 2b are butted together.

FIG. 3 shows an embodiment of the method for manufacturing a U-shaped core according to the present invention, in which the magnetic material 3 is sequentially wound onto a winding form 5 from a spool 4 in a circular winding step to form a round-wound core 6. The round-wound core 6 is removed from the winding form 5 in the zero-turning form removal process. ■After the round-wound core 6 is inserted between the concave mold 7 and the convex mold 80 in the forming process, the convex mold 8
The round-wound core 6 becomes a U-shaped core 1 by being pressurized from above.

(2) In the mold fixing step, the concave mold 7 and the convex mold 8 are fixed with tightening bolts 9 so as to maintain the shape of the U-shaped core 1. ■During the annealing process, the U-shaped core 1 remains fixed between the concave mold 7 and the convex mold 8 in the annealing furnace lO.
It is annealed inside. ■In the mold removal process, the concave mold 7 and convex mold 8 are removed, and the U-shaped core 1 is completed.

FIG. 4 shows an embodiment of the method for manufacturing an I-shaped core according to the present invention, and the round winding process and the zero-roll demolding process are the same as in FIG. (2) After the round-wound core 6 is inserted between the upper holding plate 11 and the upper holding plate 12 in the forming process, pressure is applied from the upper part of the upper holding plate 11, and the round-wound iron core 6 becomes the I-shaped iron core 2. ■
In the mold fixing step, the upper presser plate 11 and the upper presser plate 12 are fixed using the tightening bolts 9 so as to maintain the shape of the I-shaped core 2. ■
In the annealing process, the I-shaped core 2 is annealed in the annealing furnace 10 while the upper presser plate 11 and the upper presser plate 12 are fixed. (2) In the mold removal step, the upper presser plate 11 and the upper presser plate 12 are removed to complete the I-shaped core 2.

"Effects of the Invention" According to the present invention, the iron core for a stationary inductor has the following effects.

(1) Since there is no need to cut thin, hard magnetic materials, there is no need for expensive automatic cutting equipment.

(2) Work can be done continuously without cutting, so
The labor required for manufacturing the core can be reduced.

(3) Because the coil can be easily inserted into the U-shaped core,
Unlike step-lap cut iron cores, opening the core does not cause damage or deteriorate magnetic properties.

(4) Since the core has only two joint surfaces, it has better magnetic properties than stacked cores. Furthermore, if a plurality of I-shaped cores are arranged in a U-shaped core as shown in FIG. 2, the magnetic properties are further improved.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the core structure of the present invention, and FIGS. 3 and 4 show an embodiment of the method of manufacturing the core of the present invention. 5 and 6 are examples of core structures according to the prior art. Below 1... U-shaped core, 2.2a, 2b... I-shaped core, 3.3a, 3b... Magnetic material, 4...
Winding reservoir, 5... Winding form, 6... Round wound core, 7.
... Concave type, 8... Convex type, 9... Tightening bolt,
10...Annealing furnace, 11...Upper holding plate 12...
・・Upper holding plate, 13・・・・Step lap cut iron core, 14・・・・
Seam, 15...This is a stacked iron core.

Claims (3)

[Claims] (1) An amorphous magnetic material or a thin magnetic material with a thickness of 100 (μm or less) is used, and this magnetic material is continuously wound in a U-shape and an I A closed magnetic circuit is formed by abutting the core laminated surfaces of both ends of the I-shaped core against the core laminated surfaces of the open ends of the U-shaped core. Features of the core for stationary inductors. (2) a step of winding the magnetic material onto a former to form a round-wound core;
A step of removing the round-wound core from the winding form, and inserting the round-wound core into a mold having a concave mold surrounded on at least three sides and a convex mold that can be inserted into the concave mold so that the inner peripheral surfaces of the round-wound core are in close contact with each other. A patent characterized by having the steps of pressing and forming into a U-shape, fixing the mold and iron core so that they do not separate, annealing the iron core while it is inserted in the mold, and removing the mold. A method for manufacturing a U-shaped iron core as set forth in claim (1). (3) The process of winding the magnetic material onto a winding form to form a round-wound core, the process of removing the round-wound core from the winding form, and the process of attaching upper and lower press plates to the outer peripheral surface of the round-wound core so that the inner peripheral surfaces of the round-wound core are in close contact with each other. It is characterized by the following steps: a step of pressurizing the iron core through the presser plate and forming it into an I-shape, a step of fixing the holding plate and the iron core so that they do not separate, a process of annealing the iron core while being held by the holding plate, and a process of removing the holding plate. A method for manufacturing an I-shaped iron core as set forth in claim (1).