JPH03241721A - Manufacture of printed coil - Google Patents

Abstract

PURPOSE:To easily obtain an exposed terminal part by projecting the conductor of the terminal part from an insulating board, and further removing the insulator from the unnecessary part. CONSTITUTION:A hole 3 larger than a terminal part is opened by punching the necessary part of an insulating board 1 with a die or by another method, and conductors 2 are provided at both sides of the insulating board 1 by the method of adhesion, laminating or the like. Next, leaving the conductor parts 2-1 to cover the holes and the conductor circuits 2-2, the conductors are removed by etching. Then, a printed coil is made by physically stamping out the terminal parts 4, the conductor circuits 2-2, the insulating board for holding them, and some peripheral parts with a die, or by another method. In this printed coil being obtained by this, the insulating board 1 does not exists in the terminal part, and an exposed terminal part can easily be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a printed coil used in manufacturing transformers and the like.

[Conventional technology and its problems]

For the reliability of soldering, it is preferable that unnecessary insulators are not present in the terminal portion of the printed coil and only the conductor portion is exposed.

As a method for exposing the conductor, for example, Japanese Patent Laid-Open No. 1999
A method of making a hole in an insulating substrate and a conductor pasted together as described in Publication No. 0591, Utility Model Application No. 63-14697
As described in Japanese Patent No. 5, a method is known in which cut grooves are provided on the side surfaces of a laminated portion of an insulator and a conductor.

In the above method, since the conductors are connected to each other via solder, peeling may occur at the interface between the conductor and the solder when a strong force is applied. Therefore, it is desired to connect conductors even more strongly.

[Means for solving problems]

In order to solve such problems, we have discovered that a stronger connection can be achieved by making the conductor of the terminal part protrude from the insulating substrate and connecting the protruding terminal, and we are currently applying for the invention.

As a result of further studies, the inventors of the present invention discovered that if the unnecessary portions of the insulator were removed in advance, the insulating substrate would not be interposed in the terminal area, and thus an exposed terminal area could be easily obtained. This led to the invention.

That is, the present invention is a method for manufacturing a printed coil having a terminal portion protruding from an insulating substrate, which includes (a) providing a conductor on an insulating substrate having a hole larger than the terminal portion; (b) a conductor covering the hole. (c) a step of physically cutting the conductor, leaving at least the terminal portion, the conductor circuit, and the insulating substrate holding them; This is a characteristic feature.

The present invention will be specifically explained below with reference to the drawings.

FIGS. 1(a) to 1(d) schematically show the steps of the present invention. First, as shown in FIG. 1(a), an insulating substrate 1
A hole 3 larger than the terminal part is created by punching out a predetermined location using a mold, and as shown in FIG. 1(b), the adhesive and
Conductors 2 are placed on both sides of the insulating substrate 1 by a method such as lamination.
will be established. Next, as shown in FIG. 1(c), the conductor is removed by etching, leaving the conductor portion 2-1 covering the hole and the conductor circuit 2-2. Thereafter, as shown in FIG. 1(d), the parts other than the terminal part 4, the conductor circuit 2-2, the insulating substrate l holding them, and some peripheral parts are physically punched out (for example, by punching them out with a die). A printed coil is produced by cutting.

In addition, after providing conductors on both sides of the insulating substrate and before etching unnecessary conductors, or after etching unnecessary conductors and before physically cutting the unnecessary parts, conductors at the terminals can be spotted with each other. If joined using methods such as welding,
This is preferable because it can be bonded in a state free of dust and other impurities.

Furthermore, if necessary, holes may be similarly provided in the upper and lower pattern connection portions of the conductor circuit, or the connection portions may be joined by spot welding.

As another aspect of the present invention, for example, as shown in FIG. 2, the terminal portion 4 may be formed only on one side.

The insulating substrate used in the present invention may be a commonly used film-like substrate made of synthetic resin such as polyimide, epoxy resin, polyester, polyamide, urethane resin, acrylic resin, polyphenylene sulfide, fluorine resin, or polyethylene; A fibrous base material such as a glass nonwoven fabric impregnated with a synthetic resin can be used. This insulating substrate generally has a thickness of 10-odd micrometers to 1 mm, although it varies depending on the purpose and use of the insulating substrate.

The conductors provided on both sides of the insulating substrate are usually made of copper, aluminum, or the like with a thickness of about several μm to 500 μm. Furthermore, after producing the printed coil, it can be plated with other metals such as gold or solder.

〔Example〕

The present invention will be explained below with reference to Examples.

Example 1 A hole larger than the terminal portion and a hole larger than the upper and lower pattern connection portions were provided at appropriate locations on a 150 μm thick insulating substrate made of glass nonwoven fabric impregnated with B-stage epoxy resin.
Copper foil with a thickness of 35 μm is laminated on both sides of the insulating board,
The epoxy resin was dried. Next, a photoresist was provided on both sides of the film, exposed to ultraviolet light through a negative film on which a circuit pattern was drawn, and developed with a sodium carbonate solution to form a photoresist mask on the circuit pattern. Thereafter, parts other than the conductor part covering the hole where the mask was provided, the part connecting the conductor circuit part and the image part were etched with a ferric chloride solution, and the resist was removed with a sodium hydroxide solution. Then, the conductors of the terminal part and the upper and lower pattern connection parts are joined by spot welding, and the core window part is punched out using a mold, and the parts other than the terminal part are coated with epoxy resin adhesive on one side.
A 5 μm polyimide film was placed, pressed and heated to adhere and cure to form an insulating layer. Finally, the outer shape was punched out and molded to produce a printed coil.

Example 2 A hole larger than the terminal portion and a hole larger than the upper and lower pattern connection portions were provided at appropriate locations on an insulating substrate made of a 125 μm thick polyethylene terephthalate film having a polyester adhesive on both sides, and a 300 μm thick insulating substrate was formed on both sides of the insulating substrate. )
tm copper foil was pasted together using a real press. Then,
A resist was provided in a desired shape by screen printing, and portions other than the conductor portion covering the hole where the resist was provided, the portion connecting the conductor circuit portion and the image portion were etched, and the resist was removed with a trichloroethane solution. Then, the conductors of the upper and lower pattern connection parts are joined by spot welding, the core window part, the terminal part and the outer shape are punched out using a mold, and a polyester face is applied to the parts other than the terminal part and hardened to form an insulating layer. Finally, the upper and lower conductors of the terminal portion were spot welded to fabricate Pudding 1 to coil.

Example 3 A hole larger than the terminal portion and a hole larger than the upper and lower pattern connection portions were provided at appropriate locations on an insulating substrate with epoxy resin adhesive applied on both sides of a 75 μm thick polyimide film, and the thickness was A 140 μm copper foil was laminated. Next, a circuit pattern was prepared in the same manner as in Example 1, and then the conductors at the upper and lower pattern connecting portions were joined by spot welding, and the terminal portions were punched out using a die. Thereafter, an insulating layer was formed in the same manner as in Example 1, and only the surface of the terminal portion was etched with a dilute hydrochloric acid aqueous solution, and then solder plated thereon. Finally, the core window and outer shape were punched out using a die to produce a printed coil.

In each of the examples, it was possible to obtain a printed coil in which the conductor of the terminal portion was exposed and there was no intervening insulating substrate.

If you use a printed coil like the one above, the contact area between the solder and the terminal will be large during soldering in the post-process, making it possible to perform highly reliable soldering. When attaching pins to the terminals, spot welding allows for a strong connection.Furthermore, when attaching pins to the terminals, the solder that connects the pins to the terminals comes in contact over a wide area, making for highly reliable connections. .

〔Effect of the invention〕

As described above, the present invention manufactures a printed coil having a terminal portion protruding from an insulating substrate by a specific method, so that the obtained printed coil does not have an insulating substrate interposed in the terminal portion, and the exposed terminal portion is easily removed. That's what you get.

[Brief explanation of drawings]

FIGS. 1(a) to (d) are perspective views showing an outline of the steps of the manufacturing method of the present invention, and FIG. 2 is a perspective view showing a part of another example of the printed coil obtained by the present invention. . 1... Insulating substrate 2... Conductor 2-1... Conductor part covering the hole 2-2... Conductor circuit 3... Hole larger than the terminal part 4... Terminal part

Claims (2)

[Claims] (1) A method for manufacturing a printed coil having a terminal portion protruding from an insulating substrate, comprising: (a) providing a conductor on an insulating substrate having a hole larger than the terminal portion; (b) a conductor portion covering the hole; A print characterized by comprising: a step of etching the conductor while leaving the conductor circuit portion; and (c) a step of physically cutting the other part, leaving at least the terminal portion, the conductor circuit, and an insulating substrate holding them. How to manufacture coils. (2) The method for manufacturing a printed coil according to claim 1, wherein the step (b) or (c) is performed after the conductors on both sides provided in the portion corresponding to the hole larger than the terminal portion are joined. .