JPH09251916A - Transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transformer which has high working efficiency, low costs, high reliability and can be made thin. SOLUTION: The transformer has a pair of cores 14, each having approximately E-shaped section having magnetic legs 17 at both ends of the long axis of a rectangular plate and center magnetic leg at the center around which a terminal part 2 is disposed. A coil is embedded in a coil bobbin 4 held with holders 20 formed outwards from the four corners of the core 14. Grooves are cut into the terminal part 2 of the coil to position the holder and fix it to a hold part 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer used for various electronic devices.

[0002]

2. Description of the Related Art As an example of the structure of a conventional transformer of this type, a pair of substantially rectangular parallelepiped convex magnetic legs are provided at both ends of a rectangular plate, and a columnar central magnetic leg is provided at the center. A pair of rectangular cores are used to face each other, a pair of rectangular parallelepiped terminal blocks provided with flat terminals and a coil bobbin in which a copper wire is wound and an annular coil is embedded are directly connected to the magnetic leg. There is one that is stored in the space formed by the central magnetic leg and the core is fixed with tape.

[0003]

However, when the dimensions are reduced to a certain extent or less, it is very difficult to fix the core with the tape, the working efficiency is poor, and the reliability of the transformer is lowered. Further, the thickness of the tape affects the outer dimensions to increase the dimensions, which is an obstacle to thinning. Also, the tape used as the core fixing tape is
Since it is a heat-resistant tape and uses polyimide that can withstand the heat of reflow solder, it has the drawback of being expensive.

The technical problem of the present invention is that work efficiency is high,
It is an object of the present invention to provide an inexpensive and highly reliable transformer that can be thinned.

[0005]

According to the present invention, there is provided a coil bobbin in which a coil is embedded in a space formed by combining a pair of magnetic leg sides having cores having magnetic legs at both ends and a central portion of a plate-shaped substrate. A transformer held by a holder in which a coil terminal is engaged so as to be located at an open portion of the core, wherein the core has protrusions at four corners, the coil bobbin has grooves in the terminal portion, and the holder is By engaging the protrusion and the groove,
A transformer characterized by holding a core and positioning a coil bobbin is obtained.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to examples and drawings.

The transformer of the present invention, as shown in FIG.
When magnetic legs 17 are formed at both ends of a rectangular plate-shaped long axis and a cylindrical central magnetic leg 18 is formed at the center, when the center of the long axis is cut,
A pair of cores 14 having a substantially E-shaped cross section are used in combination. The core 14 has an annular recess 22 formed around the central magnetic leg 18. Since both ends of the core 14 in the direction orthogonal to the long axis are open, the terminal portion connected to the coil is exposed and the bobbin in which the coil is embedded is enclosed in the recess of the core. It has become. The core 14 has holding portions 15 protruding outward from the four corners so as to be orthogonal to the long axis.

Further, as shown in FIG. 1 (c), the coil bobbin 4 used in the transformer of the present invention is provided with terminal blocks 3 at both ends in the major axis direction, and terminals 2 are formed on the side surfaces thereof. In addition, the groove 15 for fixing the holder in the center of the terminal block 3
Are provided as a pair. Further, the coil bobbin 4 is formed with an annular coil embedding portion 10 having a central hole 12 at the center.

As shown in FIG. 3, the holder 20 used in the transformer of the present invention has holding cylinders 21 at both ends for holding the holding portions of the core. In addition, a fixing portion 23 corresponding to the groove of the core is provided at the center.

The transformer of the present invention is manufactured as follows.

First, as shown in FIG. 1A, a ring-shaped coil 9 made of a copper wire 8 wound a predetermined number of times is set on a lead frame 11 having four terminal portions 6 formed thereon. , The terminal portion 7 of the coil 9 is soldered.

As shown in FIG. 1 (b), the coil 9 and the terminal portion 7 of the coil 9 and the terminal portion 6 of the lead frame are connected and molded together with the terminal block 3 so as to be embedded.

Next, the AA portion of FIG. 1 (b) is separated from the lead frame to obtain a coil bobbin 4 as shown in FIG. 1 (c).

Further, as shown in FIGS. 1D and 1E, the terminal portion 2 separated from the vicinity of both ends of the back surface 13 of the coil bobbin 4 is bent so as to enclose the terminal base 3, It is molded in a U shape.

Next, the coil bobbin 4 is installed in the recess 22 so that the terminal block of the coil bobbin is located at the open end of the recess 22 of the core 14 shown in FIG.

Finally, the fixing portion 23 shown in FIG.
It is installed in the groove 5 to position the terminal block. In the holder 20, the holding portion 21 is expanded outward and fitted into the holding portion to fix the core, and the transformer of the present invention in FIG. 4A is completed.

[0017]

As described above, according to the present invention, the step of fixing the core by the tape is eliminated, the working efficiency is improved, the holder is not larger than the thickness of the core, and the expensive tape is used. Since there is no need to use the transformer, it is possible to provide a thin transformer that has good workability, is inexpensive, and is highly reliable.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a coil bobbin and a coil used in a transformer of the present invention. FIG. 1A is a plan view showing a coil used in the transformer of the present invention. FIG.1 (b) is a top view which shows the coil bobbin used for the transformer of this invention. FIG.1 (c) is a perspective view which shows the coil bobbin used for the transformer of this invention. FIG. 1D is a front view showing a coil bobbin used in the transformer of the present invention. FIG. 1 (e)
[Fig. 3] is a side view showing a coil bobbin used in the transformer of the present invention.

FIG. 2 is an explanatory diagram showing a core used in the transformer of the present invention. FIG. 2A is a plan view showing a core used in the transformer of the present invention. FIG. 2B is a bottom view showing the core used in the transformer of the present invention. FIG. 2C is a side view showing the core used in the transformer of the present invention.

FIG. 3 is a perspective view showing a holder used in the transformer of the present invention.

FIG. 4 is an explanatory diagram showing a transformer of the present invention. FIG. 4 (a)
FIG. 3 is a perspective view of the transformer of the present invention. FIG.4 (b) is the elements on larger scale of the transformer of this invention.

[Explanation of reference numerals] 1 transformer 2 terminal portion 3 terminal block 4 coil bobbin 5 groove 6 terminal portion (of lead frame) 7 terminal portion 8 copper wire 9 coil 10 coil embedding portion 11 lead frame 12 center hole 13 back surface 14 core 15 holding portion 16 magnetic joint 17 magnetic leg 18 central magnetic leg 19 chevron 20 holder 21 holding part 22 recess 23 fixing part

Claims (1)

[Claims] 1. A coil bobbin having a coil embedded in a space formed by combining a pair of magnetic leg sides having magnetic legs at both ends and a central portion of a plate-shaped substrate, and a coil terminal located at an open portion of the core. , The core is provided with protrusions at four corners, the coil bobbin is provided with a groove in a terminal portion, and the holder is engaged with the protrusion and the groove, A transformer characterized by holding a core and positioning a coil bobbin.