JPH073807B2 - Manufacturing method of mold type transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a method for manufacturing a molded transformer provided with a wound core made of an amorphous magnetic alloy ribbon.

(Prior Art) In recent years, there has been a demand for low loss in molded transformers, and as a material for wound cores provided in transformers in accordance with this requirement, amorphous magnetic alloy thin films excellent in iron loss and exciting current characteristics have been used. Attempts have been made to use obi. Among the amorphous magnetic alloy ribbons, iron-based amorphous magnetic alloy ribbons are used for transformer cores, but these iron-based amorphous magnetic alloy ribbons have the property of easily rusting. Moreover, the generated rust has a drawback that it deteriorates the magnetic properties and durability of the amorphous magnetic alloy ribbon. For this reason, when manufacturing a molded transformer equipped with a winding core made of amorphous magnetic alloy ribbon, rust-prevention treatment should be applied to the winding core to prevent rust from occurring in the amorphous magnetic alloy ribbon. is necessary. As a method of manufacturing a molded transformer, there is a method of combining a molded coil formed by impregnating a coil element with resin and hardening it, and a wound core. There is a problem that it is hidden by and cannot be subjected to anticorrosion treatment.

In order to deal with this problem, a wound iron core impregnated with a synthetic resin as disclosed in Japanese Examined Patent Publication No. 52-25127 is divided into two, and then the divided iron cores are joined in a state where each divided surface is joined. A method of manufacturing by a so-called C-cut core method in which a rust preventive paint is applied to the outer surface, the wound iron core is then divided, an adhesive is applied to the divided surface, and the wound iron core is assembled to a mold coil using this as a joint surface. There is.

(Problems to be Solved by the Invention) However, when this C-cut core manufacturing method is applied to a mold type transformer having a wound iron core made of an amorphous magnetic alloy ribbon having high stress sensitivity, the following results are obtained. Problems arise.
When the wound core is impregnated with the synthetic resin in order to divide the wound core into two parts, the synthetic resin penetrates between the amorphous magnetic alloy thin ribbon layers of the wound core. Since a force acts on the amorphous magnetic alloy ribbon when the invading synthetic resin is cured and shrunk, there is a problem that the magnetic characteristics of the amorphous magnetic alloy ribbon, that is, the magnetic characteristics of the wound core are deteriorated.

The present invention has been made in view of the above circumstances, and provides a method for manufacturing a molded transformer capable of performing rustproofing treatment on a wound iron core made of an amorphous magnetic alloy ribbon without deteriorating the magnetic characteristics. Especially.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above-mentioned object, a method for manufacturing a molded transformer according to the present invention includes a winding body formed by winding an amorphous magnetic alloy ribbon. A plurality of amorphous magnetic alloy ribbons are cut and developed to form a laminated body, and then the laminated body is bent into a rectangular shape to form a wound iron core. Rust-preventive coating is applied to the surface of the other part of the winding core except the yoke part where the end face joint part where both end faces are butt joined is located, and the yoke part where the end face joint part of the winding core is located is opened. The molded coil is fitted to the leg portion of the winding core, the yoke portion of the winding core is then closed, and rust preventive paint is applied to the yoke.

(Function) Since the legs of the wound core to which the molded coil is fitted are subjected to rust prevention treatment, and then the molded coil is fitted to the wound core,
Rust prevention can be applied to the entire surface of the wound core without being constrained by the mounting of the mold coil, and since a rust preventive paint is applied as the rust preventive treatment, the rust preventive treatment affects the magnetic characteristics of the wound core. Never.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

First, as shown in FIG. 2, the amorphous magnetic alloy ribbon 1 is wound in a toroidal shape to form a wound body 2.

Next, a predetermined portion of the wound body 2 is axially cut by a means such as a grindstone or a laser, and one end of this cut portion is maintained at a right angle with respect to the side surface of the wound body 2 and the amorphous magnetic The alloy ribbon 1 is developed on a plane by utilizing its elastic restoring force. As a result, as shown in FIG. 3, a large number of amorphous magnetic alloy ribbons 1 are laminated to form a laminated body 3 in the form of an isosceles trapezoid whose one end face is a right angle.

Next, as shown in FIG. 4, the laminated body 3 is divided into a plurality of laminated blocks 3A, 3B, 3C, 3D, 3E each having a stacking thickness t with a predetermined plurality (for example, about 200 sheets) as one block, and divided. The laminated blocks 3A, ..., 3E described above are sequentially re-stacked in a stepwise manner in the longitudinal direction of the ribbon by lengths of 3 / 2πt while maintaining the right angle at one end thereof.

Next, as shown in FIG. 5, a rectangular winding frame 4 having an upper lid 5 whose one end can be opened is prepared, and this winding frame 4 is positioned at the uppermost layer of the laminated body 3, that is, the innermost peripheral layer of the winding core. Laminated block 3E
Placed on the upper surface of. Then, the laminated blocks 3A to 3E of the laminated body 3 are bent and wound along the outer peripheral shape of the winding frame 4, and both end faces of the laminated blocks 3A to 3E are abutted and joined as shown in FIG. Thus, the wound iron core 6 is formed. This winding iron core 6 is an oblique butt lap joint type in which the joints at both ends of each laminated block 3A to 3E are diagonally overlapped and joined, and the joints at both ends are located corresponding to the upper lid 5 of the bobbin 4. ing.

The wound iron core 6 constructed in this way has a temperature of 360 to 400 ° C.
Annealing is performed under the condition of ~ 2 hours. By this annealing, the magnetic properties of the amorphous magnetic alloy ribbon 1 are recovered and the magnetic properties of the wound iron core 6 are improved.

Then, as shown in FIG. 7, rust-proof treatment is applied to the entire surface of the other portions, that is, the lower yoke portion of the winding iron core 6 and the leg portions on both sides, except for the upper yoke portion having the end face joint portion of the winding iron core 6. This rust-proof treatment is performed by applying a rust-preventive paint 7 such as a room temperature curing type epoxy modified alkyd paint by a method such as spraying or brushing using a spray nozzle 9 as shown in the drawing. The coating material 7 applied to the surface does not penetrate between the layers of the amorphous magnetic alloy ribbon 1 of the wound iron core 6.

Then, as shown in FIG. 8, the upper yoke portion of the wound iron core 6 is opened from the end face joint portion and vertically erected, and the coil material is impregnated with resin in a separate step and cured to produce a molded coil.
8 and 8 are fitted into the leg portions on both sides of the winding core 6, respectively, and then the upper yoke portion of the winding core 6 is horizontally bent again to close the end face joint portion.

Thereafter, as shown in FIG. 1, the upper yoke portion of the wound core 6 which has not been subjected to the rust preventive treatment is subjected to the rust preventive treatment. This rust preventive treatment is performed by spraying a rust preventive paint 7 such as an epoxy modified alkyd paint by spraying or brushing using a spray nozzle 9 as shown in the same manner as the rust preventive treatment of other parts of the winding core 6. Even in this upper yoke portion, the rust preventive paint 7 is prevented from penetrating between the layers of the amorphous magnetic alloy ribbon 1. As a result, the entire surface of the wound iron core 6 is completely covered with the rust preventive paint 7, and the rust preventive paint 7 adheres only to the surface of the wound iron core 6, so that the rust preventive paint 7 cures and shrinks. Almost no stress is applied, and the magnetic characteristics are not deteriorated.

[Effects of the Invention] As described above, according to the method for manufacturing the molded transformer of the present invention, the rust preventive paint is applied to the surface of the wound core before and after mounting the molded coil. The entire surface of the can be reliably subjected to anticorrosion treatment, and there is no fear of deteriorating the magnetic characteristics of the wound core.

[Brief description of drawings]

The drawings show one embodiment of the manufacturing method of the present invention, FIG. 1 is an explanatory view showing a molded transformer, FIG. 2 is an explanatory view showing a wound body of an amorphous magnetic alloy ribbon, and FIG. Is an explanatory view showing a state where the winding body of FIG. 1 is cut and expanded, FIG. 4 is a configuration diagram showing a laminated body composed of a plurality of laminated blocks, and FIG. FIG. 6 is an explanatory view showing a case of molding, FIG. 6 is an explanatory view showing a wound iron core, FIG. 7 is an explanatory view showing a step of applying anticorrosion treatment to legs and a lower yoke portion of the wound iron core, and FIG. 8 is a molded coil. It is explanatory drawing which shows the method of mounting to a winding iron core. 1 ... Amorphous magnetic alloy ribbon, 3 ... Laminated body, 6 ... Winding iron core, 7
… Rust preventive paint, 8… Molded coil.

Front page continued (72) Inventor Kazuo Yamada 2121 Nao, Asahi-machi, Mie-gun, Mie Prefecture Mie Factory, Toshiba Corporation (72) Eiji Shimomura 2121 Nao, Asahi-cho, Mie-gun, Mie Prefecture Toshiba Mie, Inc. In the factory (56) Reference JP-A-58-38151 (JP, A) JP-A-49-120127 (JP, A) JP-A-62-98709 (JP, A)

Claims (1)

[Claims] 1. A laminated body formed by laminating a large number of amorphous magnetic alloy ribbons by cutting and rolling a wound body formed by winding an amorphous magnetic alloy ribbon. After forming a wound iron core by bending the end of the amorphous magnetic alloy ribbon into a butt joint, the surface of the wound iron core other than the yoke portion where the end face joint is located is rustproof. Apply paint, then open the yoke part where the end face joint part of the winding core is located, fit the mold coil to the leg part of the winding core, and then close the yoke part of the winding core to this yoke. A method of manufacturing a molded transformer, which comprises applying an anticorrosive paint.