JP2005276994A - Bobbin structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bobbin structure where rattling is prevented without adding a work process at the time of assembling. <P>SOLUTION: A core 1 is stored in a bobbin 20 so that it is sandwiched with a base 3 constituting a core storage body 2 in a core storage 21 and a ceiling 11 constituting a cover body 10. Parts to be engaged 7a and 7b and engagement parts 15a and 15b are formed so that they are not mutually restrained and fixed. A polymerization part 31 can freely slide in accordance with the height of the core 1. Thus, the tolerance of the core 1 is absorbed and the core 1 is prevented from being exposed from the gap 30 of the bobbin 20. A creeping distance of the polymerization part 31 at the time of holding the core 1 is made to become not shorter than a distance obtained by adding the tolerance of the core 1 to an arbitrary creeping distance providing necessary insulating withstand pressure. Thus, a sufficient insulating distance considering the tolerance of the core is secured. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a core bobbin structure used in a common mode choke coil or the like for suppressing noise in electronic equipment.

  In order to suppress common mode noise of electronic equipment, a common mode choke coil as disclosed in Patent Document 1 is widely used. A common mode choke coil is a bobbin formed by covering a doughnut-shaped (thick annular) core such as a toroidal core with an insulating member, and a plurality of windings are wound around the bobbin. A separator for partitioning the windings is mounted.

FIG. 3 is an exploded perspective view showing such a conventional bobbin structure. In the figure, reference numeral 1 denotes a donut-shaped core formed by firing a magnetic material. Reference numeral 2 denotes a double cylindrical core container having an annular bottom 3 made of, for example, a resin material having insulating properties. A recess 4 is provided in accordance with the shape of the core 1, and the side periphery of the core container 2 is provided. The outer wall 5 and the inner wall 6 that form the surface are formed with mated portions 7 a and 7 b that are reduced in thickness so that the inside is stepped at the opening end of the recess 4. 10 is a double cylindrical lid body having an annular ceiling portion 11 made of, for example, a resin material having insulating properties, like the core housing body 2, and a recess 12 is provided in accordance with the shape of the core 1. The outer wall 13 and the inner wall 14 that form the side peripheral surface of the lid body 10 are formed with fitting portions 15a and 15b that are reduced in thickness so that the outside is stepped at the opening end of the recess 12. As shown in FIG. 4, the fitted portions 7 a and 7 b of the core housing 2 and the fitting portions 15 a and 15 b of the lid body 10 are formed to be fitted, and the core housing body 2 and the lid body 10 To form a bobbin 20 that accommodates the core 1. Inside the bobbin 20, there is provided a hollow core housing portion 21 composed of the concave portion 4 of the core housing body 2 and the concave portion 12 of the lid body 10, and the core 1 is just fit in the core housing portion 21. .
JP 11-176669 A

  However, in the conventional bobbin structure as described above, when the core 1 is accommodated in the core accommodating portion 21 of the bobbin 20, a gap is generated between the core 1 and the bobbin 20 inner surface. There was a problem that vibration sound was generated. Since the core 1 is formed by firing a magnetic material, the dimensional error (tolerance) at the time of manufacture is larger than that of the resin bobbin 20. Therefore, the core accommodating part 21 of the bobbin 20 must be formed with the maximum dimension in consideration of the dimensional error of the core 1, and when the core 1 is accommodated, a gap is inevitably generated. For example, when the height dimension of the core 1 is a ± 0.5 mm, the outer shape is b ± 0.7 mm, and the inner diameter is c ± 0.5 mm, the core housing portion 21 of the bobbin 20 is positioned in the height direction of the bobbin. It must be designed so that the minimum value is a + 0.5 mm, the minimum outer shape is b + 0.7 mm, and the maximum inner diameter is c−0.5 mm.

  As a means for solving such a problem, an elastic agent such as silicone is injected into the concave portion 4 of the core container 2 and the concave portion 12 of the lid body 10 so that there is no gap between the core 1 and the inner surface of the bobbin 20. However, since a step of injecting silicone is required, there is a problem that the number of man-hours during assembly increases.

  In view of the above problems, an object of the present invention is to provide a bobbin structure that prevents rattling without adding a work process during assembly.

  In the bobbin structure according to claim 1 of the present invention, in the bobbin structure in which the core is housed in the core housing portion formed by fitting the fitting portion of the lid and the fitted portion of the core housing body, The minimum height dimension value of the core housing portion is set to be equal to or less than the minimum height dimension value of the core, and the creeping distance of the overlapping portion where the fitting portion and the fitting portion overlap is between the core and the bobbin outside. The length is equal to or longer than the required insulation distance plus the tolerance of the core.

  If it does in this way, a core will be in the form clamped by a core container and a cover body by making the height dimension of a core accommodating part into below the minimum height dimension which considered the tolerance of the core. Even if tolerance occurs in the core, by allowing the overlapping portion where the fitting portion and the fitted portion overlap to be slidable according to the height of the core, the tolerance of the core can be absorbed, Shaking can be prevented. On the other hand, the creeping distance of the overlapping portion is required between the core and the outside of the bobbin such as the winding in order to prevent the overlapping portion from becoming too short and lowering the dielectric strength between the winding and the core. By setting the length to be equal to or longer than the length obtained by adding the core tolerance to the insulation distance, a necessary insulation distance can be ensured between the winding and the core even if the core has a tolerance.

  According to the bobbin structure of the first aspect of the present invention, it is possible to prevent the core from rattling without adding an operation process when assembling the bobbin.

  Hereinafter, a preferred embodiment of a bobbin structure according to the present invention will be described together with a manufacturing method thereof with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the same location as a prior art example, and since description of a common part overlaps, it abbreviate | omits as much as possible.

  FIG. 1 is an exploded perspective view showing a bobbin structure in the present embodiment. In the figure, reference numeral 1 denotes a donut-shaped core formed by firing a magnetic material. Reference numeral 2 denotes a double cylindrical core container having an annular bottom 3 made of, for example, a resin material having insulating properties. A recess 4 is provided in accordance with the shape of the core 1, and the side periphery of the core container 2 is provided. The outer wall 5 and the inner wall 6 that form the surface are formed with mated portions 7 a and 7 b that are reduced in thickness so that the inside is stepped at the opening end of the recess 4. 10 is a double cylindrical lid body having an annular ceiling portion 11 made of, for example, a resin material having insulating properties, like the core housing body 2, and a recess 12 is provided in accordance with the shape of the core 1. The outer wall 13 and the inner wall 14 that form the side peripheral surface of the lid body 10 are formed with fitting portions 15a and 15b that are reduced in thickness so that the outside is stepped at the opening end of the recess 12. As described above, the basic structure of the bobbin is almost the same as the conventional example shown in FIGS.

  In this embodiment, as shown in FIG. 2, the inside of the bobbin 20 is formed with a hollow core housing portion 21 composed of the recessed portion 4 of the core housing body 2 and the recessed portion 12 of the lid body 10. Since the height of the accommodating portion 21 is designed to be equal to or less than the minimum dimension value considering the tolerance of the core 1, the fitted portions 7a and 7b of the core accommodating body 2 as in the conventional example shown in FIG. In a state where the fitting portions 15a and 15b are in contact with each other, the core 1 cannot be accommodated. Specifically, for example, when the dimension in the height direction of the core 1 is a ± 0.5 mm, the core container 2 wall surface height d, the lid body 10 wall surface height e, the fitted portion 7a (fitting) in FIG. If the joint portion 15a) is assumed to be height f, the height d + e + f of the core housing portion 21 is designed to satisfy d + e + f ≦ a−0.5. Therefore, when the core 1 having a large tolerance is accommodated in the core accommodating portion 21, the core 1 cannot be completely accommodated in the core accommodating portion 21, and a gap 30 is always generated between the core accommodating body 2 and the lid body 10. Since the gap 30 is always generated, the core 1 comes into close contact with the bottom 3 constituting the core housing 2 and the ceiling 11 constituting the lid 10, and by attaching a winding, a separator, or the like, It is pinched and fixed without rattling. That is, the core accommodating portion 21 accommodates the core 1 by the bottom portion 3 constituting the core accommodating body 2 and the ceiling portion 11 constituting the lid body 10.

  Here, it should be noted that the fitted portions 7a and 7b and the fitted portions 15a and 15b are formed relatively higher (longer) than the conventional example shown in FIGS. The fitted portions 7a and 7b and the fitted portions 15a and 15b are formed relatively high, and the fitted portions 7a and 7b and the fitted portions 15a and 15b are not locked and fixed to each other. It is formed as follows. This is because the overlapping portion 31 where the fitted portions 7a and 7b and the fitting portions 15a and 15b overlap is made to be slidable, so that the tolerance of the core 1 is absorbed, and the core 1 is the bobbin 20 This is to prevent exposure from the gap 30. Since the winding is wound around the bobbin 20, it is necessary to secure an insulation distance between the winding and the core 1 according to the voltage applied to the winding. Since the core 1 is covered so as not to be exposed from the bobbin 20 having insulation (high withstand voltage) as described above, the insulation distance between the winding and the core 1 is the creepage distance x + y ( The sum of the distance x in the thickness direction and the distance y in the height direction). Therefore, the to-be-fitted parts 7a and 7b and the fitting parts 15a and 15b are required to have a creepage distance x + y of the overlapping part 31 when the core 1 is accommodated between the core 1 and the outside of the bobbin 20 such as a winding. It is configured to be equal to or greater than the distance obtained by adding the tolerance of the core 1 to the insulation distance. By doing so, a sufficient insulation distance is secured in consideration of the core tolerance.

  As described above, in this embodiment, the core 1 is attached to the core housing portion 21 formed by fitting the fitting portions 15a and 15b of the lid 10 and the fitted portions 7a and 7b of the core housing body 2. In the structure of the bobbin 20 accommodated, the minimum height dimension value (d + e + f) of the core accommodating part 21 is set to be equal to or less than the minimum height dimension value (a-tolerance) of the core 1 and the fitting parts 15a and 15b are fitted. The creepage distance x + y of the overlapping portion 31 where the joining portions 7a and 7b overlap is configured to be equal to or longer than the length obtained by adding the tolerance of the core 1 to the insulation distance required between the core 1 and the outside of the bobbin 20. .

  In this manner, the core 1 is sandwiched between the core container 2 and the lid 10 by setting the height of the core container 21 to be equal to or less than the minimum height considering the tolerance of the core 1. Become. Even if there is a tolerance in the core 1, the overlapping portion 31 where the fitting portions 15 a and 15 b and the fitted portions 7 a and 7 b overlap is made to be slidable according to the height of the core 1. Can be absorbed, so rattling can be prevented. On the other hand, in order to prevent the overlapping portion 31 from becoming too short and lowering the withstand voltage between the winding and the core 1, the creepage distance x + y of the overlapping portion 31 is set to the outside of the bobbin 20 such as the core 1 and the winding. By setting the length to be equal to or longer than the length of the insulation distance required for the core 1 plus the tolerance of the core 1, the necessary insulation distance is ensured between the winding 1 and the core 1 even if the core 1 has a tolerance. be able to. Therefore, the shakiness of the core 1 can be prevented without adding a work process when the bobbin 20 is assembled.

  In addition, this invention is not limited to the said Example, It can change in the range which does not deviate from the meaning of this invention. The shape of the core or bobbin is not limited to an annular shape, and may be any shape such as a rod shape, an arch shape, or a square shape.

It is a disassembled perspective view of the bobbin which has the bobbin structure in 1st Example of this invention. FIG. 2 is a longitudinal sectional view of the bobbin. It is a disassembled perspective view of the bobbin which has the bobbin structure in a prior art example. FIG. 2 is a longitudinal sectional view of the bobbin.

Explanation of symbols

1 core 2 core container 7a, 7b mated part
10 Lid
15a, 15b Fitting part
20 bobbins
21 Core housing
31 Superposition part

Claims (1)

In the bobbin structure in which the core is housed in the core housing portion formed by fitting the fitting portion of the lid body and the fitted portion of the core housing body, the minimum height dimension value of the core housing portion is determined. The creepage distance of the overlapped portion where the fitting portion and the fitted portion overlap is equal to or less than the minimum height dimension value of the core and the insulation distance required between the core and the outside of the bobbin. A bobbin structure characterized by being configured to be longer than the length plus tolerance.

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