JP3821355B2 - Choke coil and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a choke coil used for a power circuit of an electronic device and the like and a method for manufacturing the choke coil.
[0002]
[Prior art]
An explanatory diagram of a conventional choke coil is shown in FIG. 4, and an assembly explanatory diagram thereof is shown in FIG. As shown in FIGS. 4 and 5, the conventional choke coil has a spacer 5 attached to an I-shaped magnetic core 4 and a conductive plate 21 whose both ends are bent in a U-shape from the side. The choke coil was manufactured by fitting and combining the U-shaped magnetic core 6. Here, the step of attaching the spacer 5 to the I-shaped magnetic core 4 has the effect of improving the DC superposition characteristics by adjusting the gap between the inner wall surface of the U-shaped magnetic core 6 and the I-shaped magnetic core 4. It was essential to get.
[0003]
[Problems to be solved by the invention]
In the conventional choke coil, the lower surface of the U-shaped portion (terminal portion) of the conductive plate 21 whose both ends are bent in a U-shape protrudes from the lower surface of the I-shaped magnetic core 4. When mounted on the circuit board, only the projecting portion is in contact with the circuit board, so that the sitting is poor and rattling occurs. Therefore, the first problem is to suppress the rattling at the time of product mounting. In addition, the gap between the inner wall surface of the U-shaped magnetic core 6 and the I-shaped magnetic core 4 is adjusted by attaching the spacer 5 to the I-shaped magnetic core. Inefficiency is a drawback, and therefore the second challenge is to facilitate the manufacturing process.
[0004]
Accordingly, an object of the present invention is to prevent the rattling at the time of mounting, reduce the spacer, simplify the manufacturing process, reduce the manufacturing cost, and easily assemble the choke coil with excellent mass productivity. And a method of manufacturing the same.
[0005]
[Means for Solving the Problems]
The width of the conductive plate whose both ends are bent in a U shape is equal to or smaller than the width of the I-shaped magnetic core. Furthermore, the height of the inner side surface of the U-shaped magnetic core is approximately equal to the height of the conductive plate bent at both ends to be U-shaped. Both the bottom surface and the bottom surface of the U-shaped magnetic core are in a positional relationship that substantially contacts the circuit board. The adjustment of the inductance gap is performed by cutting one or both side surfaces of the I-shaped magnetic core joined to the U-shaped magnetic core into a concave shape.
[0006]
[Action]
The width of the I-shaped magnetic core is made equal to the width of the conductive plate bent at both ends to be U-shaped, and the height of the inner side surface of the U-shaped magnetic core is set to be U-shaped at both ends. By making the height equal to the height of the conductive plate, the grounding area at the time of product mounting increases, and stable mounting becomes possible. In addition, in the adjustment of the inductance gap, a concave air gap can be provided in advance as an external setup on the I-shaped magnetic core, so that the assembly process is reduced and the working efficiency is improved as compared with the case of attaching a spacer.
[0007]
That is, according to the present invention, a cylindrical body having a substantially rectangular parallelepiped shape and a cylindrical section having a substantially rectangular cross-section, and a portion that penetrates the cylindrical section and is exposed to the outside of the soft magnetic body are substantially perpendicular. In the choke coil formed of a conductive plate bent in the shape, the soft magnetic body is formed by joining an I-shaped magnetic core into an opening of the U-shaped magnetic core , and joining the U-shaped magnetism of the I-shaped magnetic core. A part of one or both of the joint surfaces with the core has a concave air gap, and both ends of the I-shaped magnetic core are bent into a U-shape. The conductive plate is fitted inside the conductive plate, and the height of the conductive plate is substantially the same as the height of the inner side surface of the cylindrical portion of the soft magnetic body . The mounting end surface of the conductive plate on the circuit board and the U-shaped magnetic core This is a choke coil whose open end face is on the same plane .
[0008]
Further, according to the present invention, a cylindrical body having a substantially rectangular parallelepiped shape and a cylindrical portion having a substantially rectangular cross-sectional shape, and a portion that penetrates the cylindrical portion and is exposed to the outside of the soft magnetic body are substantially perpendicular to each other. In the method of manufacturing a choke coil composed of a conductive plate bent in the shape of the I-shaped magnetic core, the soft magnetic body is formed by opposingly joining a U-shaped magnetic core and an I-shaped magnetic core. A concave air gap is formed in a part of one or both surfaces of the joint surface with the U-shaped magnetic core, and then both ends of the conductive plate are bent into a U-shape. the I-shaped magnetic core fitted into and joined by incorporating into the opening of the U-shaped magnetic core, the open end face of the mounting end surface of the circuit board of the conductive plate and the U-shaped magnetic core is flush A choke coil manufacturing method for positioning as described above .
[0009]
Further, the present invention provides a choke coil manufacturing method in which a concave air gap provided on a part of one side surface of the I-shaped magnetic core or a part of both side surfaces is formed by polishing or grinding. Is the method.
[0010]
【Example】
A choke coil and a manufacturing method thereof according to an embodiment of the present invention will be described below.
[0011]
1A and 1B are explanatory views of a choke coil according to the present invention, FIG. 1A is an external perspective view, and FIG. 1B is a partially cutaway view. In FIG. 1, a U-shaped magnetic core 3 and an I-shaped magnetic core 1 are combined to form a substantially rectangular parallelepiped cylindrical body, and the cross-sectional shape of the cylindrical portion is a substantially rectangular shape. Yes.
[0012]
2A and 2B are diagrams showing an I-shaped magnetic core 1 having a concave air gap on the side surface used for the choke coil of the present invention, FIG. 2A is a plan view, and FIG. 2B is a front view. FIG. 2 (c) shows a side view. The I-shaped magnetic core 1 was 20 mm long, 5 mm wide and 2 mm thick.
[0013]
FIG. 3 is an assembly explanatory diagram of the choke coil of the present invention. In the assembly of the choke coil of the present invention, the conductive plate 2 having both ends bent into a U-shape is fitted into the I-shaped magnetic core 1 from the side surface direction. Here, the width of the I-shaped magnetic core 1 and the width of the conductive plate 2 whose both ends are bent in a U-shape are substantially equal, and the distance between the inner walls of the conductive plate 2 bent in the U-shape is as follows. , Approximately equal to the thickness of the I-shaped magnetic core.
[0014]
Next, the cross section whose inner side surface is equal to the height of the conductive plate 2 bent at both ends is U-shaped, the U-shaped magnetic core 3 is connected to both ends where the I-shaped magnetic core 1 is fitted. It fits in the conductive plate 2 bent into the shape. Here, in the conventional choke coil, only the U-shaped portion of the conductive plate 2 whose both ends are bent in the U-shape is the ground surface, and the ratchet occurs. The end face of the conductive plate 2 and the end face of the U-shaped magnetic core 3 are on the same plane, and the area is larger than the ground area of the conventional choke coil, so that very stable mounting is possible.
[0015]
Also, the inductance is adjusted using a concave air gap by cutting one side or both sides of the I-shaped magnetic core 1 into a concave shape. In the example of FIG. 1, the concave air gaps 1a and 1b are formed on both sides by polishing or grinding, but the size, position, etc. can be set as appropriate in order to obtain desired choke coil characteristics. Conventionally, when adjusting with a spacer, work efficiency was deteriorated due to the spacer being displaced in the step of attaching the spacer and in that step. Since a concave air gap can be provided in advance, the assembly process is reduced and the assembly work efficiency is improved.
[0016]
【The invention's effect】
As described above, according to the present invention, a choke coil that is easy to assemble and has excellent mass productivity, which prevents rattling during mounting, reduces spacers, and simplifies the manufacturing process to reduce manufacturing cost. The manufacturing method can be provided.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a choke coil according to an embodiment of the present invention. FIG. 1A is an external perspective view, and FIG. 1B is a partially cutaway view.
FIG. 2 is a diagram showing an I-shaped magnetic core used in a choke coil according to an embodiment of the present invention. 2A is a plan view, FIG. 2B is a front view, and FIG. 2C is a side view.
FIG. 3 is an assembly explanatory diagram of a choke coil according to an embodiment of the present invention.
FIG. 4 is an explanatory diagram of a conventional choke coil. 4A is an external perspective view, and FIG. 4B is a partially cutaway view.
FIG. 5 is an assembly explanatory diagram of a conventional choke coil.
[Explanation of symbols]
1, 4 I-shaped magnetic core 1a, 1b Recessed air gap 2, 21 Conductive plate 3, 6 U-shaped magnetic core 5 Spacer

Claims (3)

A cylindrical body having a substantially rectangular parallelepiped shape and having a cylindrical section having a substantially rectangular cross-section, and a conductive plate that penetrates the cylindrical section and is exposed to the outside of the soft magnetic body is bent at a substantially right angle. In the choke coil, the soft magnetic body is formed by joining an I-shaped magnetic core into an opening of the U-shaped magnetic core, and joining the U-shaped magnetic core to the U-shaped magnetic core. A part of one surface or a part of both surfaces has a concave air gap, and the I-shaped magnetic core is disposed inside the conductive plate bent at both ends in a U-shape. The conductive plate has a height substantially equal to the height of the inner side surface of the cylindrical portion of the soft magnetic body, and the mounting end surface of the conductive plate on the circuit board and the open end surface of the U-shaped magnetic core are the same. A choke coil characterized by being on a flat surface . A cylindrical body having a substantially rectangular parallelepiped shape and having a cylindrical section having a substantially rectangular cross-section, and a conductive plate that penetrates the cylindrical section and is exposed to the outside of the soft magnetic body is bent at a substantially right angle. In the choke coil manufacturing method, when the soft magnetic body is formed by facing and joining a U-shaped magnetic core and an I-shaped magnetic core, the U-shaped magnetic core of the I-shaped magnetic core, A concave air gap is formed on a part of one or both of the joint surfaces, and then both ends are fitted into the inside of the conductive plate bent into a U-shape. the shaped magnetic core joined by incorporating into the opening of the U-shaped magnetic core, positioned as open end surface of the the mounting edge of the circuit board of the conductive plate the U-shaped magnetic cores are coplanar A method for manufacturing a choke coil, characterized in that:   The concave air gap provided on a part of one side surface of the I-shaped magnetic core or a part of both side surfaces is formed by polishing or grinding. Method of manufacturing a choke coil.

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