transformer

Abstract

To reduce the effects of magnetic fields while suppressing the increase in body size. [Solution] A transformer in which four windings are wound around a core, wherein four of the legs of the core are arranged in a substantially rectangular shape, and each of the four windings is wound around two adjacent legs in different combinations, and the core is provided with a second leg having a larger cross-sectional area than the four legs at a position further away from the center of the rectangle formed by the four legs, and on opposite sides of the center of the rectangle, and the windings wound around the two legs that are close to the second leg are also wound around the second leg in addition to the two legs, and the windings wound around the second leg have a greater transmission power than the windings that are not wound around the second leg.

Description

Technical Field

[0001] The present disclosure relates to transformers.

Background Art

[0002] Patent Document 1 discloses a transformer including a core having leg portions forming a magnetic path, and windings wound around the leg portions of the core.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] However, in the case of a multi DC-DC converter for 4V and 48V voltages, two transformers are required. Integrating the two transformers will cause a problem of mutual magnetic interference between them.

[0005] The present disclosure has been made in view of the above, and its purpose is to provide a transformer that can reduce the influence of magnetic fields while suppressing an increase in size.

Means for Solving the Problem

[0006] The transformer according to this disclosure is a transformer in which four windings are wound around a core, the four legs of the core are arranged in a substantially rectangular shape, the four windings are each wound around two adjacent legs in different combinations, the core has a second leg with a larger cross-sectional area than the four legs located further away from the center of the rectangle formed by the four legs, and the windings wound around the two legs located closer to the second leg are also wound around the second leg in addition to the two legs, and the windings wound around the second leg have a greater transmission power than the windings not wound around the second leg. [Effects of the Invention]

[0007] According to this disclosure, it is possible to reduce the effects of magnetic fields while suppressing an increase in body size. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view showing a transformer according to an embodiment of the present disclosure. [Figure 2] Figure 2 is a side view showing a transformer according to an embodiment of the present disclosure. [Figure 3] Figure 3 is a circuit diagram showing a transformer according to an embodiment of the present disclosure. [Figure 4] Figure 4 is a top view showing a transformer according to an embodiment of the present disclosure. [Modes for carrying out the invention]

[0009] The embodiments of this disclosure will be described below with reference to the drawings. In all the drawings of the embodiments described below, the same or corresponding parts will be denoted by the same reference numerals. Furthermore, this disclosure is not limited to the embodiments described below.

[0010] Herein, in order to explain this embodiment, the disclosed person's diligent research will be described. According to the disclosed person's knowledge, generally, one transformer is required for each auxiliary device, for example, in the case of a 14V and 48V multi-DC converter, two transformers are required. Since transformers adjust the voltage by the number of windings, it is necessary to separate the transformers where there are voltage differences. Also, when multiple auxiliary devices are used, the transformer is usually divided into multiple transformers, increasing its size, so an integrated transformer is considered. However, an integrated transformer confines two magnets in the magnetic material, so they influence each other, and simply integrating two transformers will still result in mutual influence. Furthermore, integrated transformers tend to be large in size in order to avoid magnetic saturation. Therefore, the disclosed person diligently researched and conceived of a transformer that integrates two transformers while increasing the magnetic material area of ​​the pair with the higher transmission power to prevent magnetic saturation. The embodiment described below was devised based on the disclosed person's research described above.

[0011] First, a transformer according to one embodiment of this disclosure will be described. Figures 1, 2, 3, and 4 are a perspective view, a side view, a circuit diagram, and a top view, respectively, of the transformer according to this embodiment.

[0012] As shown in Figures 1 and 2, the transformer 1 according to this embodiment is held by a bobbin 35 provided between a lower housing 10 and an upper housing 40. The magnetic materials 30 and 38 constituting the core have legs that form a magnetic path due to the current flowing through the windings 21, 31, 34, and 37. That is, the magnetic materials 30 and 38 each form rectangular prism-shaped legs. The windings 21, 31, 34, and 37 are arranged to be wound around the rectangular prism-shaped legs of the magnetic materials 30 and 38, respectively. In the transformer 1, the current flowing through the primary windings 21 and 34 generates a magnetic field in the legs (core). Then, the magnetic field generated in the windings 21 and 34 wound around the legs induces an electromotive force in the secondary windings 31 and 37, causing current to flow through the windings 31 and 37. The windings 21, 31, 34, and 37 may be hermetically sealed by a resin member (not shown) filled inside the housing 10 while housed therein.

[0013] In other words, the transformer 1 according to this embodiment is a transformer 1 in which four windings are wound around a core, the core having four legs arranged in a substantially rectangular shape, the four windings each being wound around two adjacent legs in different combinations, the core having two second legs with a larger cross-sectional area than the four legs, located further from the center of the rectangle formed by the four legs, and positioned opposite each other from the center of the rectangle, the windings wound around the two legs located closer to the second legs are also wound around the second legs in addition to the two legs, and the windings wound around the second legs have a greater transmission power than the windings not wound around the second legs.

[0014] Specifically, two transformers are provided within a single enclosure. These two transformers are equipped with four windings. Two pairs of windings are provided, and the winding direction of each pair is offset by 90° to suppress mutual magnetic interference between the two pairs of windings. In addition, the winding with the higher transmission power of each pair is wound in such a way that the area of ​​the magnetic material is larger. Here, the area of ​​the magnetic material increases as the distance from the center of the magnetic material increases. Due to the relationship between magnetoresistance, the magnetic field concentrates in areas where the loop area through which the magnetism (magnetic flux) passes is small, so the area of ​​the magnetic material is increased as the distance from the center increases.

[0015] As shown in Figures 2 and 3, windings 21 and 31 form one pair, and windings 34 and 37 form the other pair. Windings 21 and 31 are wound transversely (in the XY plane) around the center of the magnetic material. Windings 34 and 37 are wound longitudinally (in the XZ plane) around the center of the magnetic material. The surface areas of magnetic materials 30 and 38 are set to be larger as the distance from the center O increases. In Figure 4, the surface area of ​​magnetic material 30 located farther from the center O is set to be larger than the surface area of ​​magnetic material 38 located closer to the center O.

[0016] According to the above-described embodiment of the present disclosure, the four windings are wound around legs in different combinations, making them less susceptible to interference. Furthermore, since the winding with large transmission power is wound such that the area of the magnetic material is increased at a position away from the center of the entire winding, the influence of the magnetic field can be reduced while suppressing an increase in size.

[0017] Although the embodiments of the present disclosure have been specifically described above, the present disclosure is not limited to the above-described embodiments, and various modifications based on the technical idea of the present disclosure and embodiments obtained by combining the mutual embodiments can be adopted. Further effects and modifications can be easily derived by those skilled in the art. Broader aspects of the present disclosure are not limited to the specific details and representative embodiments expressed and described as above. Accordingly, various changes are possible without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Description of Reference Numerals]

[0018] 1: Transformer 10: Lower housing 21, 31, 34, 37: Winding 30, 38: Magnetic material 35: Bobbin 40: Upper housing

Claims

[Claim 1] A transformer in which four windings are wound around a core, Four of the core's legs are arranged in a roughly rectangular shape, and the four windings are each wound around two adjacent legs in different combinations. The core has a second leg, which has a larger cross-sectional area than the four legs, located at a position further away from the center of the rectangle formed by the four legs, and is positioned opposite to the center of the rectangle. The windings wound around the two legs located near the second leg are also wound around the second leg in addition to the two legs. The winding wound around the second leg transmits more power than the winding not wound around the second leg. A transformer characterized by the following features.

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