JPS6142405B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a molded transformer in which both the primary and secondary coils are charged to a high voltage potential, or one of them is charged to a high voltage potential and the other is charged to a particularly high voltage potential.

As shown in Fig. 1, this type of transformer generally has a coil 1 with a relatively high potential on the outside.
A frame 6 is arranged concentrically around the core leg 3 with the coil 2 having a lower potential inside, and both coils 1 and 2 are fixed to the core leg 3 and a yoke (not shown) by common coil receivers 4 and 5. Supported by However, in this structure, the terminal 7 of the inner coil 2 comes out at the top or bottom of the coil. In any case, the height of the core leg 3 and the diameter of the coil 2 must be greater than necessary to ensure sufficient insulation distances D ₁ and D ₂ between the terminal 7 and the frame 6 and between the terminal 7 and the core leg 3 to withstand high voltage. Therefore, the transformer became large and expensive. In addition, the coils 1 and 2 had to be manufactured separately, and therefore two types of coil casting operations and two types of molds were required, making the coils even more expensive.

The present invention has been made in view of these points, and it is an object of the present invention to eliminate the above-mentioned drawbacks and provide a compact, inexpensive molded transformer whose inner coil has a potential higher than high voltage. This object is achieved according to the invention by the following configuration.

In other words, the primary and secondary windings, which are embedded in resin and configured as cylindrical high-voltage windings, are arranged above and below the core leg in the axial direction, and the external connection terminals of both windings are connected to the outside. An auxiliary winding formed by winding a band-shaped conductor having a width corresponding to at least the total height of both windings in the axial direction is disposed between the high-voltage molded coil drawn out in the opposite direction and the iron core leg.

FIG. 2 is a structural diagram of an embodiment of the present invention, and the same reference numerals indicate those having the same functions as those described above. Primary winding (extra high voltage or high voltage) 21 and secondary winding (high voltage) 2
2 are formed into a cylindrical shape, arranged concentrically and vertically in the axial direction, and embedded in a resin 23 to form a molded coil 24 and supported by a frame 6 via a coil support 25. Then, the external connection terminals 26 and 27 are each pulled out to the outside of the coil 24, and are spaced apart from each other and placed at a location where a sufficient insulation distance can be secured from structures such as the frame 6 and the core legs 3.
Moreover, the primary winding 21 and the secondary winding 22 may be turned upside down. Furthermore, an auxiliary winding 28 is disposed between the molded coil 24 and the core leg 3, and is supported by the frame 6. There is.

As is well known, when the primary and secondary windings are arranged one above the other in the axial direction, the magnetic coupling between the two windings is poor and the impedance becomes excessive. However, by adding the auxiliary winding 28 as described above, the magnetic coupling between the primary and secondary windings becomes very good through the winding, and there is no problem at all as a transformer. Further, as mentioned above, the band-shaped conductor 28A having a width corresponding to the total height of both windings 21 and 22 in the axial direction is used for the auxiliary winding 28 as shown by the arrows in FIGS. 2 and 3.
Current flows in opposite directions to the upper and lower sides of the primary and secondary windings, which have opposite current directions, and circulates within the strip-shaped conductor 28A without the need for special split windings and connecting leads. Therefore, there is an advantage that the winding 28 can be made small.

In addition, if a terminal is put out from the strip-shaped auxiliary winding 28 and the auxiliary winding 28 has the necessary capacity, the strip-shaped auxiliary winding 28
can be a tertiary winding and can be used as a three-winding transformer. In this case, since the voltage of the tertiary winding is low, there is no need to increase the height of the core or increase the diameter of the winding for its terminals.

FIG. 4 is a structural diagram of another different embodiment of the present invention, in which the primary winding 21 and the secondary winding 22 are connected to a resin 23.
separate molded coils 41 and 42.
The structure is the same as that shown in FIG. 2 except that both molded coils are stacked one above the other in the axial direction. This is applied when the mold coils 41 and 42 are too large to be handled or when there is a limit to the amount of molding in the resin casting furnace.

As is clear from the above description, the primary winding 21 and the secondary winding 22, each configured as a cylindrical high voltage winding embedded in the resin 23, are disposed above and below the core leg 3 in the axial direction, and both At least both of the windings 21, 2 are placed between the iron core leg 3 and the high-voltage molded coils 24, 41, 42, which are formed by pulling out the external connection terminals 26, 27 of the windings, respectively, to the outside.
By disposing an auxiliary winding in which a band-shaped conductor having a width corresponding to the total height in the axial direction of 2 is wound, a small and inexpensive high-voltage molded transformer can be obtained. In addition, the positions of the terminals 26 and 27 are not limited as in the case where the conventional coils 21 and 22 are placed inside and outside, and they can be pulled out to any convenient side, so the interphase lead wires that connect them can also be placed. It is easy to install and can contribute to improving quality. Furthermore, the auxiliary winding 28 can be used as a tertiary winding. In this case, the range of use of the transformer can be further expanded.

[Brief explanation of the drawing]

FIG. 1 is a structural explanatory diagram of a conventional high-voltage molded transformer, and FIGS. 2, 3, and 4 are structural explanatory diagrams of a high-voltage molded transformer according to an embodiment of the present invention, respectively.
FIG. 2 is a diagram showing the current direction of a strip winding and another diagram illustrating a different structure. 3: Iron core, 21: Primary winding, 22: Secondary winding,
23: Resin, 24, 41, 42: High voltage molded coil, 26, 27: Connection terminal, 28: Auxiliary winding,
28A: Band-shaped conductor.

Claims (1)

[Claims] 1. A primary winding and a secondary winding each configured as a cylindrical high voltage winding embedded in a resin are disposed above and below in the axial direction of the core leg, and both windings are connected to the outside. An auxiliary winding made of a band-shaped conductor having a width corresponding to at least the total height of both windings in the axial direction is arranged between the high-voltage molded coil and the iron core leg, each of which has a connecting terminal drawn outward. Features: High voltage molded transformer. 2. A high-voltage molded transformer according to claim 1, characterized in that the primary winding and the secondary winding are integrally molded with resin with a predetermined axial distance between them. vessel. 3. The transformer according to claim 1, characterized in that the primary winding and the secondary winding are each configured as separate molded coils, and both molded coils are stacked vertically in the axial direction. High voltage molded transformer. 4. The high voltage molded transformer according to claim 1, wherein the auxiliary winding is a tertiary winding of the transformer.