JPH0129047B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a thin transformer used as a general power transformer.

Structure of conventional example and its problems Conventionally, as shown in Figs. 1 and 2, the manufacturing method of a thin transformer is to form a bobbin-shaped transformer in which a rectangular column core 1 made of laminated strips of iron core is wound with a coil 2. The prismatic core 1 is inserted into an insulator 3 such that both ends of the prismatic core 1 protrude from both ends of the insulator 3. The prismatic core 1 is sandwiched between the two frame-shaped cores 4, 5, and the frame-shaped cores 4, 5 and the prismatic core 1 constitute a Japanese-shaped magnetic circuit.

Then, the frame-shaped cores 4, 5 and the prismatic core 1 are joined by fitting the clamps 6, 7 having a U-shaped cross section to the outside of the frame-shaped cores 4, 5.

However, with this manufacturing method, there may be variations in the dimensions of the prismatic core 1 and the frame-shaped cores 4, 5, or variations in the dimensions and spring strength of the fasteners 6, 7. Therefore, the prismatic core 1 and the frame cores 4 and 5
There may be a gap at the joint. As a result, there are problems in that the excitation current, leakage magnetic flux, and loss of the transformer increase, and furthermore, vibration and humming noise increase.

OBJECTS OF THE INVENTION In view of the above-mentioned drawbacks, the present invention provides a method for manufacturing a thin transformer in which each core is securely joined without creating any gaps.

Structure of the Invention In order to achieve the above object, the present invention involves bonding a prismatic core and a frame-shaped core with an adhesive, applying bonding pressure to the prismatic core and frame-shaped core by mechanical pressure, and then After passing a direct current through the coil wound around the prismatic core to generate an electromagnetic attraction force between the prismatic core and the frame-shaped core, the mechanical pressure is released, and after the adhesive has hardened, the coil is This was a method of cutting off the direct current that was flowing.

With this manufacturing method, regardless of variations in the dimensions of the prismatic core and frame core, each core can be reliably joined, and a transformer with sufficient strength can be manufactured. no longer needed. Moreover, since mechanical pressure is not required after direct current is passed through the coil, it is possible to manufacture thin transformers using inexpensive equipment.

DESCRIPTION OF THE EMBODIMENTS As shown in FIG. 3, a prismatic core 8 made of laminated strips of iron core is inserted into a bobbin-shaped insulator 10 around which a coil 9 is wound. Fix it so that both ends stick out. Then, a prismatic core 8 is placed between two frame-shaped cores 11 and 12 having a required cross-sectional area. The prismatic core 8 and the frame cores 11, 12 are the prismatic core 8 and the frame cores 11, 12.
12 to form a Japanese character shape, and are fixed by adhesives 13 to 16.

The prismatic core 8 and frame-shaped cores 11, 12, which are bonded by adhesives 13 to 16, are mechanically pressed (approximately 50 to
100Kg). The adhesives 13-16 are then evenly distributed at the joint between the prismatic core 8 and the frame cores 11, 12. Next, as shown in Figure 5, the coil 9
Lead wires 19 and 20 are drawn out from the coil 9, and a DC current is applied to the coil 9 by a power source 21. By passing DC current through the coil 9, electromagnetic force (approx. 20 to 50 AT) is generated.
occurs, and even after the mechanical pressure is released, the prismatic core 8 and the frame-shaped cores 11 and 12 remain reliably joined because of mutual attraction force. Then, after the mechanical pressure is released, a direct current may be passed through the coil 9 until the adhesives 13 to 16 are cured.

Adhesives 13 to 16 are used to bond the prismatic core 8 and the frame cores 11 and 12, and the bonding is ensured by mechanical pressure and electromagnetic attraction. , 12, it is possible to manufacture a transformer with stable characteristics and no gaps. In particular, in a magnetic circuit in which a prismatic core 8 is sandwiched between upper and lower frame cores 11 and 12, the number of joints increases, resulting in high magnetic resistance and poor efficiency. By ensuring the bonding, the characteristics can be significantly stabilized and the efficiency can be improved. In addition, it has sufficient strength due to reliable bonding, and also has low excitation current and leakage magnetic flux.
It is possible to manufacture a transformer that suppresses increases in loss, vibration, and humming noise.

Effects of the Invention As described above, the present invention applies mechanical pressure to a prismatic core and a frame-shaped core that are bonded together with an adhesive, and then applies a direct current to a coil wound around the prismatic core.
By joining the prismatic core and frame core using electromagnetic attraction until the adhesive hardens, the gap between the cores can be maintained even if the dimensions of the prismatic core or frame core vary. Therefore, an efficient transformer with stable characteristics can be manufactured without the need for fasteners as in the past.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of a transformer manufactured by a conventional thin transformer manufacturing method, FIG. 2 is a perspective view of the same transformer, and FIG. 3 is a thin transformer manufacturing method according to an embodiment of the present invention. Figure 4 is a partially sectional front view showing a state in which mechanical pressure is applied to the transformer, and Figure 5 is a state in which direct current is flowing through the coil of the transformer. FIG. 8...Prismatic core, 9...Coil, 10...Insulator, 11, 12...Frame-shaped core, 13-16...Adhesive.

Claims (1)

[Claims] 1 Wrap a coil around a prismatic core via an insulator,
The prismatic cores are bonded to opposing central parts of two frame-shaped cores having a required cross-sectional area so that the prismatic cores and the frame-shaped cores form a magnetic circuit in the shape of a Japanese character. After that, mechanical pressure is applied to the prismatic core and frame-shaped core, and then a direct current is passed through the coil wound around the prismatic core to bond the prismatic core and frame-shaped core together. After generating an attractive force by electromagnetic force, the mechanical pressure is released, and after the adhesive has hardened, the direct current flowing through the coil is cut off, and the thin film core is bonded to the prismatic core and the frame-shaped core. A method of manufacturing transformers.