JPH0260201B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a method of manufacturing a lightweight and ultra-thin transformer. <Prior art and its problems> The small transformer 1 that has been manufactured in the past has a primary winding 3, a winding bobbin 2, and a winding bobbin 2 as shown in FIG. 1B.
Wind the secondary winding 4, solder the beginning and end of the primary winding to the primary terminals 3a, 3a', and the beginning and end of the winding of the secondary winding to the secondary terminals 4a, 4a', respectively. C in the center hole 2a of the bobbin 2 in Fig. 1.
The central convex portion 5a of the silicon steel plate iron core 5 formed into an E shape as shown in FIG. The cores 6 are joined alternately in a laminated manner to close the magnetic path, and the iron cores 5 and 6 are fixed with tape, metal fittings, metal bands, etc. 7, and then insulating varnish, wax, resin, etc. After impregnation, a small transformer 1 as shown in FIG. 1A was completed. In addition, for other small transformers 1 , the iron core to be used may be E/I type as shown in FIG. 1D, or
A ferrite core molded into an E/E shape may also be used. However, in the case of such a conventional small transformer 1 , which uses a large number of silicon steel plates, the cores must be inserted and stacked one by one, which requires a lot of man-hours and skill. Along with small transformers using ferrite cores, satisfactory characteristics as a transformer cannot be obtained unless the size of the core satisfies a certain level of height and volume considering the shape of the core. Therefore, all of these components are fairly tall components used in printed wiring boards, and are difficult to make thin, such as amplifiers, high frequency boosters, interphones, etc., which require ultra-thin components. It has the disadvantage that it cannot be used as a low-frequency or high-frequency transformer for office machinery, a power transformer, etc. <Object of the present invention> The present invention was made in view of the drawbacks of the above-mentioned conventional small transformers, and is applicable to amplifiers, high frequency boosters, interphones, and office equipment that require ultra-thin transformers. The purpose of the present invention is to provide an ultra-thin transformer that can be used as low-frequency and high-frequency transformers, power transformers, and the like. <Structure of the present invention> Therefore, the present invention has a central hole, and the upper and lower plates of the bobbin for winding the winding wire have concave notches in the portions where the upper and lower cores are fitted, and the fitting portions are formed. An ultra-thin bobbin, a roughly U-shaped silicon steel core having a desired area, a plurality of sheets stacked one on top of the other, each having a front edge bent inward, the front edges interlocking with each other alternately; The inwardly bent front edge of the core of this silicon steel plate is inserted into the center hole of the bobbin from the left and right sides.
This is an ultra-thin transformer characterized by a structure in which two cores are inserted and the cores are mechanically pressed and clamped or bonded with adhesive. <Embodiments of the present invention> Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 2A is a perspective view showing the bobbin 10 of the ultra-thin transformer according to the present invention, and FIG. 2B is a perspective view of the bobbin 10 .
It is a sectional view taken along the B line. In the figure, the bobbin 10 is connected to upper and lower bobbin plates 12.
a, 12a' are joined by a support frame 13, and a hole 1 into which the core is fitted is provided in the center of the bobbin 10 .
1 will be provided. Furthermore, the upper and lower bobbin plates 1 of the bobbin 10
2a, 12a' are provided with recessed notch fitting portions 12b, 12b' into which a flat surface portion of the core, which will be described later, is fitted into the central hole 11. Upper/lower bobbin plate 12
A coil primary winding and a secondary winding 17 are wound in a space 12c surrounded by a and 12a'. The winding start and winding end of each winding are terminals 14a and 14b.
... is soldered to complete the process of producing the ultra-thin bobbin 10 . Next, the core 15 is made by overlapping a plurality of silicon steel plates as shown in FIG. 3B to obtain a desired area 15a,
15b, 15b', and have a U-shape, the tip of which is bent inward.
Molded to hold. Core 15 is bobbin 10
Notch fitting portions 12b provided on the upper and lower bobbin plates,
The front edge portions 16a and 16b are shaped to be open so as to fit into the front edge portion 12b'. In addition, the front edges 16a and 16b bent inward are fitted onto the bobbin 10 as shown in FIG. However, the joint surface 16 of these front edges 16a, 16b
c may be flat as shown in FIG. 3B, or may have a shape in which the joining surfaces are shifted one by one and interlocked as shown in FIG. 3A. The ultra-thin transformer according to the present invention is completed as shown in the completed diagram shown in FIG. 5 by the assembly method shown in FIG. 4. That is, after the core 15 on one side in one direction is placed on the bobbin 10 around which the primary winding and the secondary winding 17 are wound, mechanical pressure is applied and the core 15 is clamped or bonded with an adhesive.
The core 15 on one side in the other direction (on the left side in the drawing) is placed by mechanically applying pressure and clamping or by adhering with an adhesive to complete the arrangement. Thereafter, the core 15 is fixed with a metal band or the like, and the coil is impregnated with varnish, wax, resin, etc. to complete the coil. <Effects of the Present Invention> The ultra-thin transformer of the present invention can obtain even better transformer characteristics by using a unidirectional magnetic material. Furthermore, since the core of the embodiment of the present invention has a U-shape with only one cut and opening, it is possible to obtain an efficient transformer with less loss of magnetic permeability, and the core packing work can be simplified. It has the advantage of being simple. The ultra-thin transformer completed in this way has a thickness of
A transformer with a width of 4.2 m/m, a width of 35 m/m, and a width from front to back of 22 m/m was obtained. Therefore, it has become possible to fully use it as an ultra-thin transformer for amplifiers, high-frequency boosters, interphones, and low-frequency and high-frequency power supplies for office machinery that require ultra-thin components. .

[Brief explanation of drawings]

Fig. 1A is a perspective view for explaining a conventional small transformer, Fig. 1B is a sectional view taken along the line A-A in Fig. 1A, and Figs. 1C and D are used in a conventional small transformer. FIGS. 2A and 2B are perspective views and BB line sectional views for explaining the bobbin used in the ultra-thin transformer of the present invention,
3A and 3B are perspective views for explaining the core used in the ultra-thin transformer of the present invention, FIG. 4 is an assembly diagram for explaining the method of assembling the ultra-thin transformer of the present invention, FIG. 5 is a perspective view showing a completed ultra-thin transformer according to the present invention. 1...Small transformer, 2...Small bobbin, 3,4
...Primary and secondary windings of small transformers, 5, 6...Core of small transformers, 7...Fixing metal fittings of small transformers, 8, 9...Ferrite cores, 10...For ultra-thin transformers Bobbin, 11...Central hole, 12...
Upper and lower bobbin plates, 13... Support frame, 14... Terminal, 15... Ultra-thin transformer core, 16... Front edge of core, 17... Winding wire.

Claims (1)

[Claims] 1. A bobbin having a central hole for winding a winding wire, and a plurality of silicon steel plates having a desired area and having a front edge bent inward and formed into a U-shaped cross section. A method for manufacturing an ultra-thin transformer, comprising stacking cores and fitting the front edge of the core into the center hole of the bobbin. 2. The method of manufacturing an ultra-thin transformer according to claim 1, wherein the inwardly bent front edges of the silicon steel plate core are arranged to interlock alternately. 3. Manufacturing the ultra-thin transformer according to claim 1, wherein two cores are fitted into the central hole of the bobbin, facing each other from both the left and right sides. Method. 4. The front edge of the core to be fitted into the central hole of the bobbin is first shaped to be slightly open, and after the core is inserted, mechanical pressure is applied and the core is clamped or bonded with an adhesive. A method for manufacturing an ultra-thin transformer according to claim 1, characterized in that: