JP2009206111A - Transformer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transformer which employs a configuration in a thin-thickness shape of low overall height, and can obtain a sufficient creepage distance between, for example, a secondary-side pin terminal and a core to secure a space/creepage distance corresponding to specifications of a safe standard. <P>SOLUTION: A resin-made bobbin 1 is formed in a thin-thickness shape having base plates 6 projected from both ends of a cylinder portion 5 in a flat shape, wherein a plurality of pin terminals 2, ... are embedded in and provided to end surfaces of the base plates, a wire material 3 is wound around the cylinder portion 5, and a core 4 is assembled on the base plates. One of the base plates, for example, to be a secondary side, is provided with a barrier 8 along the array of pin terminals 2, ..., and the barrier 8 is further provided integrally with a projection portion 9 along the array of pin terminals 2, ... At least one of the base plates 6 to be the secondary side is provided on both sides with side walls 7. Thus, the barrier, projection portion, and side walls are thus provided, for example, to the secondary side to obtain a long creepage distance. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a transformer that has a substantially flat plate shape and is thin and downsized. More specifically, the present invention relates to an insulating property between a pin terminal provided on an end surface of a base plate and a core assembled on the base plate. Regarding improvement.

  One of transformers employs a thin shape configuration with a low overall height in applications such as a DC-DC converter. This is because transformers are being made thinner and smaller in the same way as other electronic components. The thin transformer is supposed to be used for so-called surface mounting, and is often formed in the shape of a strip whose longitudinal dimension is extended according to the demand for higher capacity.

  In this type of transformer, the bobbin is formed in a thin shape from a resin or the like. The bobbin is integrally formed by projecting a base plate at both ends of a flat cylindrical portion, and a plurality of pin terminals are embedded in the end surface of the base plate. And it is the structure which assembles a core on a base board while winding a wire around the cylinder part.

  The core is formed from a ferrite material. The core is a single component that is insulated from both the primary side and the secondary side, but is considered as either the primary side or the secondary side when considering insulation according to safety standards. Therefore, it is necessary to improve the insulation between the pin terminal on the secondary side and the core, for example, from the insulation according to the safety standard, and, of course, ensure a sufficient amount of creepage distance as well as sufficient clearance. This is a design requirement.

As a technique regarding the creeping distance between the pin terminal and the core, there are proposals as seen in, for example, Patent Documents 1 and 2. These do not have a thin-shaped configuration, and the bobbin has a structure including a support portion that is positioned so as to project the terminal portion at both ends of the cylindrical portion and protrude downward. And it is the structure of the block shape which winds a wire around an upper cylinder part, and assembles a core to the said cylinder part side.
JP 2002-118023 A JP-A-11-297535

  As described above, thin transformers are often formed in the shape of a strip with an extended longitudinal dimension in response to a demand for higher capacity, and pin terminals are disposed at both ends in the longitudinal direction. The space distance and the creepage distance can be sufficiently secured between the pin terminals on the secondary side and the secondary side. However, the core is located at the center and is adjacent to both the primary side and the secondary side, and is considered to be the primary side, for example. Therefore, for example, there is a problem that the space / creeping distance becomes insufficient between the secondary side and the core due to the adjacent arrangement, and appropriate measures are taken to secure the space / creeping distance corresponding to the safety standard specification. Need.

  The object of the present invention is to solve the above-mentioned problems, and the object of the present invention is to adopt a thin shape configuration with a low overall height, for example, a sufficient creepage distance can be obtained between the pin terminal on the secondary side and the core. An object of the present invention is to provide a transformer capable of ensuring insulation corresponding to the specification of the standard.

  In order to achieve the above-described object, the transformer according to the present invention has a bobbin formed in a thin shape using an electrically insulating material such as a resin, and the bobbin has a base plate attached to both ends of a flat cylindrical portion. In the transformer where a plurality of pin terminals are embedded in the end surface of the base plate and a wire rod is wound around the cylindrical part and the core is assembled on the base plate, the pin terminals are aligned in one of the base plates. A barrier along the (row) is integrally provided, and a convex portion along the row of pin terminals is integrally provided on the barrier (claim 1).

  Also, the bobbin is formed in a thin shape using an electrically insulating material such as resin, and the bobbin is integrally formed by projecting a base plate at both ends of a flat cylindrical portion, and on the end surface of the base plate In a transformer in which a plurality of pin terminals are embedded, a wire rod is wound around a cylindrical portion, and a core is assembled on a base plate, a barrier along an array of pin terminals is integrally provided on one of the base plates, and a pin is further provided on the barrier. A recess is provided integrally along the terminal arrangement direction (claim 2).

  Moreover, it is good to set it as the structure which provides a side wall integrally in both sides about one side of a base board. Furthermore, the core may be configured by combining an I-type core and a B-type core (Claim 4), or may be configured by combining an I-type core and an E-type core (Claim 5).

  With this configuration, in the present invention, for example, on the secondary side, the barrier is located between the pin terminal and the core, and the barrier is provided with a convex portion or a concave portion, so that the creeping distance can be increased. . In addition, when side walls are provided on both sides, a creeping distance can be increased for the side.

  In the transformer according to the present invention, the barrier is located between the pin terminal and the core, and a convex portion or a concave portion is provided on the barrier. Side walls are provided on both sides. Therefore, for example, a sufficient creepage distance can be obtained between the secondary pin terminal and the core. As a result, it is possible to secure a space and creepage distance corresponding to the safety standard specification.

  FIG. 1 shows a preferred first embodiment of the present invention. In this embodiment, the transformer is provided by forming a resin bobbin 1 which is one of electrically insulating materials in a thin shape and embedding a plurality of pin terminals 2 at both ends of the bobbin 1. . The wire 3 is wound around the bobbin 1 and the core 4 is assembled.

  As shown in FIG. 2, the bobbin 1 is formed by forming a cylindrical portion 5 around which the wire 3 is wound into a thin flat strip shape, integrally forming base plates 6 at both ends of the cylindrical portion 5, Pin terminals 2 are embedded in the end face.

  The pin terminals 2 are bent at a portion protruding from the end face of the base plate 6 into a crank shape. And it mounts by making the joining site | part of the front-end | tip of the pin terminal 2 contact the land pattern of a printed circuit board, and soldering. The soldering is generally performed by a reflow heating method.

  The base plate 6 is integrally provided with side walls 7 on both sides. The side walls 7 are barriers that extend the creepage distance for each side portion. Pin terminals 2 project from the end face of the base plate 6 to form terminal portions thereof. Therefore, for example, the barrier 8 is integrally provided on one of the secondary sides. This barrier 8 is formed thick along the row (pinning direction) in which the pin terminals 2. Further, this barrier 8 is integrally provided with a convex portion 9. The convex portion 9 is formed along a line in which the pin terminals 2 are arranged, and serves as a barrier that extends the creeping distance for the portion.

  The core 4 is configured to combine two of an I-type core 41 and a B-type core 42, and the B-type core 42 is assembled from above with the I-type core 41 fitted into the cylindrical portion 5 of the bobbin 1. . The core 4 is not limited to the combination of the I-type core 41 and the B-type core 42 as in the present embodiment. For example, the I-type core and the E-type core may be combined. That is, the structure which makes an I-type core contact the tip part of three legs of an E-type core is taken.

  Such a thin transformer is assembled in an inverter transformer, for example, and is preferably applied to a drive system such as a thin liquid crystal display. In this case, the primary-secondary space / creeping distance is such that the barrier 8 is located between the pin terminals 2 and the core 4 and the protrusion 8 is provided on the barrier 8, so that the creepage distance is increased. Obtainable. Moreover, since the side wall 7 is provided on both sides, a creeping distance can be increased for the side. And the protrusion length of the convex part 9 can be changed suitably, and a creeping distance can be adjusted appropriately.

  Therefore, for example, a sufficient creepage distance can be obtained between the secondary pin terminals 2 and the core 4 and a distance corresponding to the specification of the safety standard can be secured.

  4, 5 and 6 show a second preferred embodiment of the present invention. In this embodiment, the transformer is substantially the same as in the first embodiment, and the resinous bobbin 1 is formed in a thin shape, and a plurality of pin terminals 2 are embedded in both ends of the bobbin 1, The wire rod 3 is wound around the bobbin 1 and the core 4 is assembled. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment, and the description is abbreviate | omitted.

  In the second embodiment, the configuration of the bobbin 1 is varied. That is, for example on the secondary side of the bobbin 1, the barrier 8 has a configuration in which the convex portion 9 is not provided, and the concave portion 10 is integrally provided in the barrier 8. The recess 10 is formed along the row of pin terminals 2... And serves as a barrier that extends the creepage distance for the portion.

  In this case as well, the distance between the primary and secondary sides is the same as in the first embodiment. The barrier 8 is located between the pin terminals 2 and the core 4, and the barrier 8 is provided with a recess 10. Therefore, a long creepage distance can be obtained. Moreover, since the side walls 7 are provided on both sides, the creepage distance can be increased for the sides. And the depth and width | variety of the recessed part 10 can be changed suitably, and a creeping distance can be adjusted appropriately.

  Therefore, for example, a sufficient creepage distance can be obtained between the secondary-side pin terminals 2 and the core 4, and a space and creepage distance corresponding to the safety standard specification can be ensured.

1 is a perspective view showing a first embodiment of a transformer according to the present invention. It is a perspective view which isolate | separates and shows a core about the transformer shown in FIG. FIG. 3 is a cross-sectional view of the transformer shown in FIGS. 1 and 2. It is a perspective view which shows 2nd Embodiment of the trans | transformer which concerns on this invention. FIG. 5 is a perspective view showing a core separated from the transformer shown in FIG. 4. FIG. 6 is a cross-sectional view of the transformer shown in FIGS. 4 and 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bobbin 2 Pin terminal 3 Wire rod 4 Core 5 Cylindrical part 6 Base board 7 Side wall 8 Barrier 9 Convex part 10 Concave part 41 I type core 42 Ro type core

Claims (5)

A bobbin is formed in a thin shape using an electrically insulating material such as resin, and the bobbin is integrally formed by projecting a base plate at both ends of a flat cylindrical portion. In a transformer in which a pin terminal is embedded and a wire is wound around the cylindrical portion and a core is assembled on the base plate,
A transformer, wherein a barrier along the arrangement direction of the pin terminals is integrally provided on one of the base plates, and a convex portion along the arrangement direction of the pin terminals is further provided integrally with the barrier. A bobbin is formed in a thin shape using an electrically insulating material such as resin, and the bobbin is integrally formed by projecting a base plate at both ends of a flat cylindrical portion. In a transformer in which a pin terminal is embedded and a wire is wound around the cylindrical portion and a core is assembled on the base plate,
A transformer characterized in that a barrier along the row of pin terminals is integrally provided on one of the base plates, and a recess along the row direction of the pin terminals is further provided on the barrier.   The transformer according to claim 1, wherein side walls are integrally provided on both sides of one of the base plates.   The transformer according to any one of claims 1 to 3, wherein the core is configured by combining an I-type core and a B-type core.   The transformer according to any one of claims 1 to 3, wherein the core is configured by combining an I-type core and an E-type core.

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