JP2011071320A - Transformer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transformer for achieving high inductance while reducing size and weight. <P>SOLUTION: The transformer 1 includes a pair of magnetic substrates 2. The magnetic substrates 2 each includes a pair of grooves 3 which are formed on one surface 21 and reaching both ends of the magnetic substrate 2, first wirings 4 provided on the grooves 3, and second wirings formed in accordance with the first wirings 4 on sides 22 on both ends of the magnetic substrate 2. The first wirings 4 and the second wirings are electrically connected to each other to form a loop-like coil. The pair of the magnetic substrates 2 are bonded by allowing the grooves 3 to face each other so that the loop-like coils can be magnetically coupled. The first wirings 4 are extended to both ends of the magnetic substrates and electrically connected to the second wirings of the sides, thereby forming the loop-like coils. Thus, a main magnetic flux passing region surrounded by the loop-like coils can be widened up to a size of the magnetic substrates 2 and high inductance can be achieved. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a transformer including a magnetic substrate and a loop coil.

  In recent years, there has been a demand for miniaturization and weight reduction of power supplies used in small and lightweight electronic devices, and there has been a problem of miniaturization and weight reduction of transformers, which are relatively large components in power supply circuits. Accordingly, there is known a transformer in which two magnetic substrates 102 on which loop-like coils 106 as shown in FIG. 7 are prepared and both substrates are joined so that the respective loop-like coils 106 face each other.

  Further, in such a transformer formed by forming a loop-shaped coil on a magnetic substrate, one that suppresses leakage of magnetic flux to the outside by adjusting the position of the loop-shaped coil is known (for example, Patent Document 1).

  However, in the transformer as described above, since the size of the loop coil is suppressed in the magnetic material substrate, it is difficult to achieve high inductance in a small configuration.

JP 2005-317724 A

  The present invention solves the above-described problems, and an object of the present invention is to provide a transformer that can achieve high inductance while reducing the size and weight.

  In order to achieve the above object, a first aspect of the present invention provides a transformer comprising a pair of magnetic substrates and a loop coil, wherein each of the magnetic substrates is provided on one surface and both ends of the substrate. A pair of grooves reaching each other, a first wiring provided in each of the grooves, and a second wiring provided on the side surfaces of both ends of the substrate corresponding to the first wiring, the first wiring and The second wiring is electrically connected to each other to form the loop-shaped coil, and each magnetic substrate is joined with the grooves facing each other so that the loop-shaped coils are magnetically coupled to each other. is there.

  According to a second aspect of the present invention, in the transformer including the first and second magnetic substrates and the loop coil, the first magnetic substrate is provided on one surface and is provided at both ends of the substrate. A pair of reaching grooves, at least a pair of first wirings provided in each of the grooves, and second wirings provided corresponding to the first wirings on both side surfaces of the substrate, The wiring and the second wiring are electrically connected to each other to form at least two loop coils, and the surface of the first magnetic substrate provided with the groove and the second magnetic substrate are face-to-face bonded. The two coils are magnetically coupled.

  According to the first aspect of the present invention, since the first wiring extends to both ends of the magnetic substrate and is electrically connected to the second wiring on the side surface to form the loop-shaped coil, the main magnetic flux passage surrounded by the loop-shaped coil is formed. The region can be widened to the size of the magnetic substrate, and high inductance can be achieved while reducing the overall shape.

  According to the invention of claim 2, since the first wiring extends to both ends of the first magnetic substrate and is electrically connected to the second wiring on the side surface to form the loop-shaped coil, it is surrounded by the loop-shaped coil. The main magnetic flux passage region can be widened to the size of the first magnetic substrate, and high inductance can be achieved while reducing the size as in the first embodiment. Further, it is only necessary to provide a groove in one of the magnetic substrates, and since the positional accuracy of the bonding between the first magnetic substrate and the second magnetic substrate may be low, manufacturing is facilitated.

The perspective view which abbreviate | omitted illustration of the 2nd wiring in the trans | transformer which concerns on embodiment of this invention. (A) is the perspective view which also illustrated the 2nd wiring in the same transformer seen from the A direction of FIG. 1, (b) is the same perspective view seen from the B direction of FIG. The perspective view which showed only the loop-shaped coil in one board | substrate of a pair of magnetic body board | substrates of the transformer. The side view in case one magnetic substrate consists of a some laminated substrate in the same transformer. The perspective view which omitted illustration of the 2nd wiring in the transformer concerning the modification of the above-mentioned embodiment. (A) is the perspective view which also illustrated the 2nd wiring in the same transformer seen from the A direction of FIG. 5, (b) is the same perspective view seen from the B direction of FIG. The perspective view of the magnetic substrate which comprises the conventional transformer.

  A transformer according to an embodiment of the present invention will be described with reference to FIGS. The transformer 1 includes a pair of magnetic substrates 2 and 2. Each of the magnetic substrates 2 includes a pair of grooves 3 provided on one surface 21 and reaching both ends of the magnetic substrate 2, first wirings 4 provided in the grooves 3, and side surfaces on both ends of the magnetic substrate 2. 22 includes a second wiring 5 provided corresponding to the first wiring 4. The first wiring 4 and the second wiring 5 are electrically connected to each other to form a loop coil 6. 1 and 2, one of the loop coils 6 and 6 provided on each of the upper and lower magnetic substrates 2 and 2 is a primary side, and the other is a secondary side. In FIG. 3, only one loop coil 6 on the primary side or the secondary side is shown.

  In the present embodiment, the loop coil 6 is configured with two turns on each of the primary side and the secondary side, but the number of turns is arbitrary. A pad 24 connected to the second wiring 5 is formed on the surface 23 opposite to the surface on which the groove 3 of the magnetic substrate 2 is provided, and is connected to an external wiring (not shown). The pair of magnetic substrates 2 and 2 are joined with the grooves 3 facing each other so that the respective loop-shaped coils 6 are magnetically coupled to each other, whereby the transformer 1 is configured. The bonding between the magnetic substrates 2 is performed by, for example, an adhesive.

  For example, ferrite can be used for the magnetic substrate 2, and copper can be used for the first wiring 4 and the second wiring 5, for example. The groove 3 is formed in the magnetic substrate 2 by counterboring or the like. The first wiring 4 is formed by electroplating, printing, or the like, and the second wiring 5 is formed by electroplating or the like. When the magnetic substrate 2 is not an insulator, the first wiring 4 and the second wiring 5 are insulated and separated by covering the entire surface with an insulating layer such as an oxide film. As shown in FIG. 4, one magnetic substrate 2 may be formed by joining a plurality of laminated substrates 7 with metal thin films 71.

  Next, the function and effect of the transformer 1 configured as described above will be described. In the transformer 1 of the present embodiment, the first wiring 4 extends to both ends of the magnetic substrate 2 and is electrically connected to the second wiring 5 on the side surface 22 to form the loop coil 6. The surrounded main magnetic flux passage region can be widened to the size of the magnetic substrate 2. Thereby, it can be set as high inductance. Further, since the first wiring 4 does not have a loop shape in the surface 21 and extends in one direction along the groove 3, the first wiring 4 extends in the extending direction of the groove 3 when the pair of magnetic substrates 2 are joined. Even if they deviate, the influence of positional deviation can be suppressed to a small level.

(Modification)
A transformer according to a modification of the present embodiment will be described with reference to FIGS. In this modification, the first wiring 4 is not formed on each of the pair of magnetic substrates 2 and 2 as in the above embodiment, but the first wiring 4 and the second wiring 5 are provided only on one magnetic substrate 2. A pair of loop coils 6 is formed. The transformer 1 includes a first magnetic substrate 2a and a second magnetic substrate 2b, and a pair of grooves 3 is formed only on the first magnetic substrate 2a. It is not formed on the substrate 2b. Each groove 3 has two pairs of first wirings 4, and the side surface 22 has a second wiring 5 corresponding to each of the first wirings 4. Each first wiring 4 and second wiring 5 are electrically connected to each other to form two loop-shaped coils 6 including a first loop-shaped coil 6a and a second loop-shaped coil 6b. The first loop coil 6a and the second loop coil 6b are magnetically coupled on the primary side and the secondary side, respectively. The surface of the first magnetic substrate 2a where the groove 3 is provided and the second magnetic substrate 2b are face-to-face joined to form the transformer 1. In this modification, the two loop coils 6a and 6b are each configured with two turns, but the number of turns is arbitrary.

  With this configuration, the main magnetic flux passage region surrounded by each loop-like coil 6 is widened to the size of the first magnetic substrate 2a as in the transformer 1 according to the first embodiment. Can do. Thereby, it can be set as high inductance. Further, the step of providing the groove 3 in the second magnetic substrate 2b is omitted, and the positional accuracy of the bonding between the first magnetic substrate 2a and the second magnetic substrate 2b may be low, so that it is easy to manufacture. . Further, since the pad is formed on one surface, it is easy to join with the external wiring.

  In addition, this invention is not restricted to the structure of the said embodiment, A various deformation | transformation is possible in the range which does not change the meaning of invention. For example, the pair of grooves 3 may not be parallel, and the grooves 3 may not be straight but may be curved.

DESCRIPTION OF SYMBOLS 1 Transformer 2 Magnetic substrate 2a 1st magnetic substrate 2b 2nd magnetic substrate 21 Surface 22 Side surface 3 Groove 4 1st wiring 5 2nd wiring 6 Loop coil

Claims (2)

In a transformer including a pair of magnetic substrates and a loop coil,
Each of the magnetic substrates corresponds to a pair of grooves provided on one surface and reaching both ends of the substrate, a first wiring provided in each of the grooves, and a first wiring on a side surface of both ends of the substrate. A second wiring provided, and
The first wiring and the second wiring are electrically connected to each other to form the loop coil,
Each of the magnetic substrates is joined with the grooves facing each other so that the loop coils are magnetically coupled to each other. In a transformer comprising first and second magnetic substrates and a loop coil,
The first magnetic substrate includes a pair of grooves provided on one surface and reaching both ends of the substrate, at least a pair of first wirings provided in the grooves, and side surfaces on both ends of the substrate. A second wiring provided corresponding to the first wiring,
The first wiring and the second wiring are electrically connected to each other to form at least two loop coils;
A transformer characterized in that a surface of the first magnetic substrate provided with a groove and the second magnetic substrate are face-to-face bonded, and the two coils are magnetically coupled.

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