JPH1041141A - Transformer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transformer whose floating capacity is small and which can increase coupling without using relay terminals. SOLUTION: A transformer is formed by stacking primary and secondary windings and combining a core 4 from upside and downside. Primary windings include a first winding circuit consisting of two or more winding coils which need balance. Each winding coil of the first winding circuit is comprised of flat coils 3b and 3d. The secondary windings include a second winding circuit consisting of two or more winding coils. Each winding coil of the second winding circuit is comprised of flat coils 3a and 3c. The flat coils 3b and 3d of the first winding circuit and the flat coils 3a and 3c of the second winding coil are stacked with a space in between in a direction crossing the plane of the flat coil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a transformer,
More specifically, the present invention relates to a transformer used in electronic equipment such as a pulse transformer for communication and a power transformer having the same voltage output of plus and minus.

[0002]

2. Description of the Related Art Conventionally, this type of transformer has a configuration in which a winding is wound on a winding frame having flanges at both ends, and the next winding is wound around the previously wound outer periphery.

FIG. 8 is a perspective view showing an example of a conventional transformer. In FIG. 8, a transformer 50 is configured such that a winding 53 is applied to a bobbin 52 having pin terminals 51 implanted at both ends of a lower flange, and an E-type and an I-type core or an E-type and an E-type core are mounted. It had.

FIG. 9 is a circuit diagram of the transformer shown in FIG. Referring to FIG. 8, a pair of first and second primary windings P1 and P2 and a pair of first and second secondary windings S1 and S2 are provided via a core 54. Have been. Reference numerals 55a and 55b in the figure are relay terminals for division.

FIG. 10 is a schematic sectional view showing an example of the configuration of the winding of the transformer shown in FIG. Referring to FIG.
The first and second primary windings P1, P2, and the first and second secondary windings S on the first and second primary windings P1 and P2 in this order from the inside of the second winding portion 56.
1, S2, and further thereon, the first and second primary windings P1, P2 are wound again.

FIG. 11 is a diagram showing another example of the winding of the transformer shown in FIG. Referring to FIG. 11, a first secondary winding S1, a first primary winding P1, and a second secondary winding on the first secondary winding S1, are sequentially arranged from the inside to the winding portion 56 of the bobbin 52. A second primary winding P2 is sequentially wound on the line S2.

[0007]

In the prior art transformer, for example, if there are two windings that need to be balanced, a bifilar winding 2 having the same winding structure is used.
This simultaneous winding is performed.

Further, if good coupling is required between the relationship between the winding requiring the balance and the other windings (primary and secondary windings), the conventional technique will be described with reference to FIG. As shown in (1), one of the windings is divided by half the number of turns, and a sandwich winding sandwiching the other winding is performed.

The problem here is that, as shown in FIG. 9, if the winding is divided while maintaining the bifilar winding, the terminals 55a and 55b for relaying are required, and extra terminals are required. Otherwise, it cannot be split.

Further, as shown in FIG. 11, when the bifilar winding is stopped, a difference in length of the winding occurs between the upper winding and the lower winding, and the balance is deteriorated. The bifilar winding is
Since the two wires are in close contact, the stray capacitance in the two windings increases, affecting the characteristics. Specifically, it has the disadvantage that the self-resonant point is lowered and the usable band is narrowed.

Accordingly, it is an object of the present invention to provide a transformer having a small stray capacitance and capable of increasing the coupling without using a relay terminal.

[0012]

According to the present invention, in a transformer having primary and secondary windings stacked on top of each other and combined with a core from above and below, the transformer of the primary and secondary windings is provided. At least one of them includes a first winding circuit composed of two or more winding coils that need to be balanced,
A transformer, wherein each of the winding coils of the first winding circuit is formed of a planar coil, and each of the planar coils is stacked apart from each other in a direction intersecting a plane formed by the planar coil. Is obtained.

According to the present invention, in the transformer, the other of the primary winding and the secondary winding is connected to a secondary winding.
A second winding circuit comprising at least two winding coils, wherein each of the winding coils of the second winding circuit comprises a planar coil, and wherein the first winding circuit and the second winding circuit A transformer is obtained in which the planar coils of the line circuit are alternately stacked and stacked in a direction intersecting the plane of the planar coil.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a transformer according to an embodiment of the present invention. Referring to FIG. 1, the transformer 10 includes:
A bobbin 2 having pin terminals 1 planted at both ends of a lower flange, a plurality of planar coils 3a, 3b, 3c, 3d, which are winding coils wound around a winding portion of the bobbin; And an EI-type core 4 attached to the EI type. More specifically, the core 4 includes a magnetic leg penetrating the plane coils 3a, 3b, 3c, 3d in the axial direction, and the plane coils 3a, 3b, 3d.
An E-shaped core having magnetic legs covering both sides of c and 3d, and an I-shaped core attached to the end of the magnetic legs of the E-shaped core. The first coils are configured by the planar coils 3b and 3d, and the second coils are configured by the planar coils 3a and 3c.

FIG. 2 is a diagram showing a circuit configuration of the transformer of FIG. As shown in FIG. 2, a first winding circuit is provided via a core 4, and the first winding circuit is divided into a pair of first and second primary windings P1, P2. Are the planar coils 3b and 3d.

Further, a second winding circuit is provided opposite to the first winding circuit via the core 4, and the second winding circuit includes a pair of divided first and second winding circuits. 2 are planar coils 3a and 3c, which are the secondary windings S1 and S2.

FIG. 3 shows the bobbin 4 of the transformer shown in FIGS.
FIG. 3 is a cross-sectional end view mainly showing a plane coil. As shown in FIG. 3, the planar coil uses a self-bonding wire or the like and has a shape that spreads out of the winding. Such winding portions are sequentially arranged from the top in the axial direction of the bobbin 3 in the order of a planar coil 3a as the first secondary winding S1, a planar coil 3b as the first primary winding P1, and a second coil 3b. The planar coil 3 which is the secondary winding S2
c and the planar coil 3d which is the second primary winding P2 are arranged at predetermined intervals in the axial direction.

In particular, the first and second parts needing a balance.
Planar coils 3b, 3d forming primary windings P1, P2
Are configured such that their outer dimensions and thickness are substantially the same.

Referring to FIGS. 1 to 3, the stacking order is such that another planar coil is sandwiched between the planar coils that need to be balanced. The core 4 is incorporated into the transformer from above and below. As described above, the first and second primary windings P1 and P2 that need to be balanced are used.
Has the same wire winding length and path, and balance is maintained regardless of the distance between the two coils.

The other first and second primary windings S
1, S2 is improved by being incorporated between the windings and by coupling in the plane area of the planar coil.

FIG. 4 shows an example in which the transformer of FIG. 1 is used for transmitting and receiving AMI codes. As shown in FIG. 4, adjacent one ends of the primary windings P1 and P2 are connected, and voltages having opposite polarities are input to the other ends. As described above, in the AMI code, a balance is required to make the pulse waveforms of the primary windings P1 and P2 the same.

FIG. 5 shows an example in which a transformer is used for phantom power supply. In FIG. 5, the primary windings P1 and P2 need to be balanced so that an unbalanced current is not generated and a load is not placed on the core of the transformer. Further, the coupling allows a wider frequency band to be transmitted.

FIG. 6 is a diagram showing the longitudinal current unbalance characteristic indicating the degree of balance of the transformer in FIG. 1, and also shows the characteristic of the transformer according to the prior art. As shown in FIG. 6, the transformer according to the embodiment of the present invention clearly has a lower longitudinal current imbalance than that according to the prior art, and this tendency is particularly remarkable on the high frequency side.

FIG. 7 is a diagram showing the insertion loss band as a measure of the degree of coupling of the transformer of FIG. 1, and also shows the characteristics of the transformer according to the prior art. As shown in FIG. 7, the transformer according to the embodiment of the present invention has a smaller insertion loss than that according to the prior art, and particularly, a large difference appears on the high frequency side.

As described above, in the transformer according to the embodiment of the present invention, the balance can be maintained by manufacturing the coils of the winding circuit requiring the balance into the same size and shape as the planar coil. Since this balance is not affected by the stacking position order, the coupling can be enhanced by the stacking order with other windings, that is, by alternately stacking.

[0027]

As described above, according to the present invention, it is possible to provide a transformer in which balance and coupling are simultaneously improved without increasing the number of terminals.

[Brief description of the drawings]

FIG. 1 is a diagram showing a transformer according to an embodiment of the present invention.

FIG. 2 is a diagram showing a circuit configuration of the transformer of FIG.

FIG. 3 is a sectional end view mainly showing a bobbin and a winding of the transformer of FIGS. 1 and 2;

FIG. 4 is a diagram showing an example in which the transformer of FIG. 1 is used for transmitting and receiving AMI codes.

FIG. 5 is a diagram showing an example in which the transformer of FIG. 1 is used for phantom power supply.

FIG. 6 is a diagram showing a longitudinal current unbalance characteristic indicating a degree of balance of the transformer according to the embodiment of the present invention, and also shows a result of the prior art.

FIG. 7 is a diagram showing a band of insertion loss as an indicator of the degree of coupling of the transformer according to the embodiment of the present invention, and also shows the characteristics of the transformer according to the related art.

FIG. 8 is a perspective view showing an example of a conventional transformer.

FIG. 9 is a circuit diagram of the transformer of FIG. 8;

FIG. 10 is a schematic cross-sectional view showing one configuration example of a winding of the transformer of FIG.

FIG. 11 is a diagram showing another example of the winding of the transformer of FIG. 9;

[Explanation of Signs] 1 pin terminal 2 bobbin 3 winding 3a, 3b, 3c, 3d plane coil 4 core 10 transformer 50 transformer 51 pin terminal 52 bobbin 53 winding 54 core 55a, 55b relay terminal 56 winding part

Claims (2)

[Claims] 1. A transformer comprising primary and secondary windings stacked on top of each other and combined with a core from above and below, wherein at least one of the primary and secondary windings needs to be balanced. A first winding circuit comprising two or more winding coils, wherein each of the winding coils of the first winding circuit comprises a planar coil, and each of the planar coils comprises a plane coil forming the planar coil. A transformer characterized by being stacked apart from each other in a direction intersecting with. 2. The transformer according to claim 1, wherein the other of the primary winding and the secondary winding includes a second winding circuit including two or more winding coils. Each of the winding coils of the second winding circuit is formed of a plane coil, and each of the first winding circuit and the plane coil of the second winding circuit crosses the plane of the plane coil. A transformer characterized by being alternately stacked in a direction.