JP2571825Y2 - Flat transformer - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a flat transformer having a low board mounting height when mounted on a board, in which a coil conductor is formed on a primary side coil, a thin resin board having rigidity, and a front and back two-layer structure. The present invention relates to a flat transformer using a primary coil having a structure that can be easily fitted to a coil bobbin.

[0002]

2. Description of the Related Art Conventionally, in this type of flat transformer,
As shown in FIG. 4, a flat coil 4 corresponding to a primary coil
Is usually formed by spirally winding an adhesive-coated conductor. However, it is difficult to manufacture such a conventional primary coil by winding an insulated copper wire having a circular cross section in a plane. However, there is a drawback that the electrical characteristics also vary greatly.

[0003]

In the present invention, the primary coil is not formed in a flat plate shape by using an adhesive-coated electric wire.
A spiral conductor that is wound in the same direction on both sides of the board around the center frame of the coil bobbin where the center magnetic leg of the magnetic core is inserted on both sides of the hard and thin resin insulation board, and formed at the center of the spiral The two-sided through-holes that pass from the front surface to the back surface of the substrate connecting the spirals on the front and back sides are integrally connected by conductors filling the two-sided through-holes to form a primary-side coil. The secondary coil is formed.

[0004]

In order to form a primary coil, for example, a copper foil, which is a good electrical conductor, is attached to both surfaces of a resin insulating substrate made of a hard and thin electric insulating material, and a spiral coil is formed on the coil bobbin. A spiral coil is formed by etching or plating a copper plate that has been previously glued to the substrate so that the coil on the front surface and the coil on the back surface are wound in the same direction around the center frame. Then, the conductors of the spiral coils on the front and back sides are connected by the conductors filled in the through-holes on both sides to form a primary side coil.

That is, according to the present invention, a mounting terminal is provided at each end, and a center magnetic leg of a magnetic core is inserted into the center where pin terminals for connecting terminals of a primary coil and a secondary coil are integrally formed with the mounting terminal. A coil bobbin made of a resin molded body provided with a central frame, a secondary coil made of a U-shaped flat copper plate with an insulating film interposed on both sides, and a primary coil made by winding a copper wire many times into the coil bobbin. In a flat transformer that is laminated and assembled with split magnetic cores from both upper and lower surfaces,
The spiral coil is formed by winding or winding the spiral coil on the both surfaces of the hard resin insulating substrate in the same direction on both sides of the hard resin insulating substrate. A flat transformer characterized by being connected to a double-sided through-hole formed in the center of the hard resin insulating substrate and filled with a double-sided through-hole integrated with a spiral conductor formed on the front and back sides.

[0006]

[Function] Since the spiral conductor formed on both sides of a resin insulating substrate made of a hard and thin electric insulating material made of glass epoxy resin or the like, the spiral conductor on the substrate surface is to be bent with a small curvature. The spiral coil on the front side and the spiral coil on the back side have the same winding direction, and when a current flows through the coil, the magnetic fields created by the spiral coils on the front and back sides are wound in directions that urge each other, The connection of the spiral coil on the front and back is made by providing holes penetrating on the front and back surfaces of the board at the center of the spiral, filling the holes with conductors and integrally forming and connecting with the conductors of the coils formed on both the front and back of the board The primary coil can be easily handled and has high reliability without causing cracks in the conductor.

[0007]

FIG. 2 shows a primary coil of a flat transformer according to the present invention, in which spiral conductors 8 are formed on both sides of a resin insulating substrate 6 which is hard and thin but has little flexibility. The coil bobbin shown in FIG. The spiral conductor 8 is formed on the front surface and the back surface of the resin insulating substrate 6 with a center hole 17 passing through the center frame 16 of the center 5 as a center. The spiral conductors 8 formed on the front and back surfaces of the resin insulating substrate 6 are filled with the conductors and connected to the through-holes 7 on both sides at the center of the spiral.
Both ends of the spiral conductor are connected to pin terminals 15 attached to both ends of the coil bobbin 5 by connecting portions 9 and 10. FIG. 1 is an exploded perspective view of the flat transformer according to the present invention, in which a mounting terminal 13 for mounting on a board at both ends and a coil bobbin 5 to which a pin terminal 15 implanted integrally with the mounting terminal 13 are attached. The secondary coil copper plate 3 electrically insulated on both sides by the film 14 and the primary coil 2 configured in the same manner as shown in FIG. 2 are laminated, and the end of the conductor of each coil is connected to the pin terminal of the coil bobbin. 15 and connect
The magnetic core 1 is inserted and assembled into the central frame 16 of the coil bobbin 5 and the central hole 17 of the primary coil from both the upper and lower directions of the coil bobbin, and the outer periphery is fixed with one-sided adhesive tape. I do. FIG. 3 is a plan view of the completed flat transformer according to the present invention.

[0008]

[Effect of the Invention] A flat transformer in which a primary coil formed by spirally forming an adhesive-coated copper wire and a secondary coil formed of a U-shaped flat copper plate are laminated on a coil bobbin and a divided magnetic core is assembled and formed. Conventionally, the primary coil formed by spirally forming an adhesive-coated copper wire into a coil is formed on both sides of a hard and less flexible resin-insulated substrate by a spiral coil in the same winding direction on both sides of the substrate around the center hole. The spiral coil formed on both sides is formed into a primary coil in which a conductor is filled and connected to the through holes at both sides at the center of the spiral, thereby incorporating a highly reliable primary coil which is easy to manufacture. Flat transformers can now be provided.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a flat transformer according to the present invention.

FIG. 2 is an external perspective view of a primary coil of the flat transformer according to the present invention.

FIG. 3 is a plan view of the flat transformer according to the present invention;

FIG. 4 is an exploded external perspective view of a conventional flat transformer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic core 1a Central magnetic leg 2 Primary coil 3 Secondary coil copper plate 4 Flat coil 5 Coil bobbin 6 Resin insulating substrate 7 Double-sided through hole 8 Spiral conductor 9, 10 Connection part 11 Flat coil connection part 12 For magnetic core fixing Tape 13 Mounting terminal 14 Insulating film 15 Pin terminal 16 Center frame 17 Center hole

Claims (1)

(57) [Scope of request for utility model registration] 1. A mounting terminal on both ends, and one mounting terminal
An insulating film is interposed on both sides of a coil bobbin made of a resin molded body having a center frame into which a center magnetic leg of a magnetic core is inserted at the center where a pin terminal for connecting a terminal of the secondary coil and a terminal of the secondary coil is planted. In a flat transformer formed by laminating a secondary coil composed of a U-shaped flat copper plate and a primary coil formed by winding a copper wire many times on the coil bobbin and assembling a split magnetic core from both upper and lower surfaces, The spiral coil formed by winding or winding the spiral coil on both surfaces of the hard resin insulating substrate in the same direction on the both sides of the hard resin insulating substrate is formed by etching or plating the conductive foil made of a good conductor. A flat truss formed by connecting to a double-sided through-hole penetrating the hard resin insulating substrate formed at the center by a conductor filling a double-sided through-hole integrated with a spiral conductor formed on the front and back sides. Nest.