JPS5840808A - Balanced-balanced type transformer - Google Patents

Abstract

PURPOSE:To eliminate an increase in parallel equivalent capacity and to make a transformer with a reasonal price as well by a method wherein a bobbin used for the transformer is placed in parallel with the axial core of an iron core to divide into two and half each of the primary winding having the reverse winding direction respectively and the similar secondary windings located on the respective primary windings are provided on the bobbin and respective windings are connected in series. CONSTITUTION:The bobbin for a transformer placed in parallel with the axial core of an iron core is divided into two and half each of the primary winding, Ia andIb having the reverse winding direction respectively is wound on the base section of the bobbin respectively. Half each of the secondary winding IIa and IIb having the reverse winding direction in the same way is respectively wound on the primary windings and the ends of the windings of the primary windingsIa andIb are connected in series and those of the secondary windings are also connected in series. In this way, the neutral points of the primary windings and the secondary windings become zero electrical potential. Then, insulators provided between these windings are not required and parallel equivalent capacity against these windings becomes small.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a balanced-to-balanced transformer, and more particularly to a balanced-to-balanced transformer in which both the primary balanced winding and the secondary balanced winding are multilayer windings.

The balanced-balanced type is widely used for purposes such as coupling between circuits and impedance matching, and most of them are constructed as shown in FIG. In Fig. 1, the primary balanced winding 1 and the secondary balanced winding 2 are wound around a devin 3, and there is an insulator such as selvedge paper 4 or insulating tape between the primary balanced winding ml and the secondary balanced winding 2. The structure is such that the . FIG. 2 shows an equinodal circuit for the transformer of FIG. 1. The reason why conventional transformers insert insulating paper 4 as shown in Figure 1 is to reduce the inter-winding capacitance C8 on the wiring shown in Figure 2 and lessen the effect on the parallel equivalent capacitance co. Generally used.

However, from the point of view of winding manufacturability, it is difficult to continuously wind windings using an automatic winding machine aimed at lowering costs, as it involves inserting selvedges between windings, which is a factor that reduces winding efficiency. It has become.

The purpose of the present invention is to enable continuous winding by an automatic winding machine, so that even if supermargins between windings are removed, the parallel equivalent capacitance for each primary and secondary winding does not increase. The object of the present invention is to provide a balanced transformer.

According to the present invention, in a balanced-to-balanced transformer in which both the primary balanced winding and the secondary balanced winding are multilayer windings, the two sections use bins, and the primary winding has a rod in each section of the bin. La and l are wound in opposite directions with different numbers of turns.
It is composed of two windings 1a and 1b, and the winding ends of the windings 1a and lb are connected on the side that is in contact with the secondary winding wound on the upper part, and the upper secondary winding is connected to the upper part of the primary winding. The primary winding is composed of two windings, Ha and I[b, which are wound in opposite directions to each other with the number of turns A in each section of the garlic bottle, and the primary winding is wound at the bottom. A balanced-to-balanced transformer is proposed in which the winding ends are connected on the side in contact with the line.

Embodiments of the balanced-balanced transformer according to the present invention will be described in detail below.

FIG. 3 shows one embodiment of the winding structure of a transformer according to the present invention, in which the devin 11 is divided into two parts, and the primary winding is a rod winding for each division of the devin, and the winding directions are opposite to each other. It consists of two windings la and lb wound so that Connect the wire ends via external terminals. The upper secondary winding is similar to the primary winding, but consists of two windings, la and lb, which are wound in opposite directions to each other, with each rod being wound in each section of the bottle. configure and its Il
The winding ends of each of the windings a and b are connected to the primary winding wound at the lower part (the winding start side in FIG. 3) through external terminals. A circuit diagram of the transformer of FIG. 3 is shown in FIG. Toto (Ia.

It should be noted that although the winding directions of lb, lla, and lb are opposite, since the winding start or winding ends are connected, the direction of the generated voltage is the same. In a transformer configured as shown in Figures 3 and 4, if the windings (a and Ib or la and nb are perfectly balanced, the midpoint will be at zero potential. Therefore, the primary The low potential portions of the winding and the secondary winding are close to each other, and the high potential portions of the secondary winding are distanced from each other.

On the other hand, the distribution of the inter-winding capacitance is large in the portions where the primary winding and secondary winding are close to each other, and becomes small in the portions where the primary winding and the secondary winding are far apart. Therefore, in the balanced-balanced transformer according to the present invention, the potential is low in the adjacent portions where the interwinding capacitance is large, so that the parallel equivalent capacitance for the primary or secondary winding due to the interwinding capacitance is extremely reduced. It is possible to make it smaller.

As explained in detail above, the present invention focuses on the fact that the parallel equivalent capacitance is generated due to the potential difference between the capacitances between the windings.
The adjacent part of the next winding is set to almost zero potential. This allows lI! between the primary and secondary windings! Equilibrium without insertion of edges −
The primary winding caused by the interwinding capacitance of a balanced transformer, 1 m (
This is an improved parallel equivalent capacitance for the secondary winding) and can be applied to transformers manufactured by continuous winding operations using an automatic winding machine to reduce the cost of the transformer. is a curious dog.

[Brief explanation of the drawing]

Figure 1 shows an example of the winding structure of a conventional balanced-balanced transformer.
Fig. 2 is a wiring diagram of the transformer shown in Fig. 1, Fig. 3 is an embodiment of a winding structure of a balanced-balanced transformer according to the present invention, and Fig. 4 is a wiring diagram of the transformer shown in Fig. 3. It is. In FIG. 3, IJ is divided into two bins, 1ml1lb is a primary balanced winding, and Ha and Ilb are secondary balanced windings. Patent applicant Fujitsu Ltd. Patent attorney Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney Yukio Uchida Patent attorney Akira Yamaguchi

Claims (1)

[Claims] In a balanced-to-balanced transformer in which both the primary balanced winding and the secondary balanced winding are multilayer windings, a two-section bobbin is used, and the primary winding has one turn for each section of the debin and the winding direction is different. 7'c I a , I
The windings la and lb have their winding ends connected on the side that is in contact with the secondary winding wound on the upper part, and the upper secondary winding is connected to the upper part of the primary winding. To? Consisting of two windings of II a + nb wound in each section of the bottle with a number of turns of W so that the winding directions are opposite to each other, and the side in contact with the primary winding wound at the bottom. A balanced-balanced transformer characterized in that the winding ends are connected at