JPH0553296U - Box type noise filter case - Google Patents

Abstract

(57) [Abstract] [Purpose] To form a box-shaped noise filter housed in a thin metal case made of a good conductor, without causing solder connection between the case body and lid, solder flow may occur in the filter circuit. It is a box-type noise filter case that can be assembled without any need. [Structure] A lower projection 5 for positioning the lower surface of the lid and an upper projection 4 for engaging the lid 1 with the case body 3 are attached to the inside of the upper portion of the case body 3 for housing the noise filter circuit 10, and the lid 1 is elastic. And a hole 2 that engages with the upper protrusion 4 is provided in a flange 8 that is made of a good metal conductive material and that has an opening.
The case 2 and the lid 1 are engaged with each other by engaging the hole 2 with the protrusion 4 and positioning by the lower protrusion.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to the structure of a box-type noise filter case of a box-type noise filter for the purpose of preventing electromagnetic noise inserted into a power supply circuit.

[0002]

[Prior Art]

 Conventionally, this type of noise filter case has been tin-plated or solder-plated on a copper plate for the purpose of removing external electromagnetic noise from the noise filter circuit inside the case and shielding the electromagnetic noise from the filter circuit to the outside. A resin filter is used for the noise filter in the metal case and the one that allows the electromagnetic noise characteristics from the device characteristics. The case of the noise filter in the metal case is the case body 3 and lid shown in Fig. 3. 1 is soldered and the case body 3 and the lid 1 are fixed at the soldering part, so that the solder flows into the noise filter circuit, and the man-hours required to remove the flux adhering to the case However, there was a drawback that it was expensive and expensive.

[0003]

[Problems to be solved by the device]

 In order to eliminate these drawbacks, the present invention has an object to provide a structure for fixing a lid to a case body in a noise filter case without soldering the case body and the lid.

[0004]

[Means for Solving the Problems]

 In the case of a small case, the metal case body used for the box-type noise filter (hereinafter referred to as the case) has a protrusion on the inside of the case. In a small case, a minimum of 2 pieces on each side, 4 pieces in total, 4 pieces in total, 8 pieces on both sides. Providing protrusions arranged in parallel on the bottom of each piece, contacting in the length direction of the case and bending the end face, there are multiple holes on the side of the elastic metal plate with the shape that opens upward It is characterized in that the end portion having elasticity is contact-fixed to the inner end surface of the case body to fix the case body and the lid without soldering by providing the portions.

That is, the present invention is a case for a box type noise filter, which comprises a case body and a lid made of an electrically conductive thin metal plate, faces inward toward the upper part of the case body, and is parallel to the side surface to the lower surface. And the lower side has a higher height than the side surface and the upper and lower sides have a plurality of protrusions on both sides, and the elastic upper and lower sides of the flat plate are in contact with and bent along the inner wall of the case body. An open collar is provided, and a lid provided with a hole for contacting the lower surface of the case body with the lower surface and engaging with the upper protrusion is formed so as to be fitted and fixed to the case body. It is a characteristic box-type noise filter case.

[0006]

[Action]

 In the case of a box-type noise filter case that uses a metal case, conventionally, the contact surface between the case and the lid is soldered, and the noise filter circuit is completely wrapped with a metal conductor to prevent the radiation noise of electromagnetic noise to the noise filter circuit. The radiation noise of the electromagnetic noise from the noise filter circuit was removed, but when the filter case body and the lid are made of a good electrically conductive material, the electromagnetic shielding effect can be achieved without soldering between the case body and the lid. Because of the large size, this is a device that was developed this time, and it has a two-tiered lower projection on the top of the case body, which is parallel to the bottom of the case body, and has a brim with an opening bent upward along the longitudinal direction. The lower surface of the lid made of a body plate is aligned, and a hole that fits into the protrusion of the upper case of the case provided inside the case body is provided at the position of the protrusion of the upper collar of the case body of the flange of the lid. After the parts that form the noise filter are housed in the filter case body, when engaging the holes on both sides of the lid with the protrusions of the filter case body, the tip of the brim of the lid folded over the lid is the filter. The filter case body and the lid are in close contact with the inner surface of the case body, and the filter case body and the lid are in surface contact with each other at the flange part, and they are fitted and fixed, resulting in a large electromagnetic interference effect. No soldering is required at the joint part.

[0007]

【Example】

 An embodiment of the present invention will be described with reference to the drawings. 1 is an exploded perspective view of a box type noise filter case according to the present invention, and FIG. 2 is an external perspective view of a box type noise filter using the box type noise filter case according to the present invention. In the case of the box type noise filter case according to the present invention shown in FIG. 1, two upper projections 4 are provided on the metal case body 3 of electrically conductive material, one on one side of the case body, and a total of four locations on both sides. Lower protrusions 5 are provided below the upper protrusion 4 in parallel to the bottom surface and higher than the case surface, so that two lower protrusions 5 are formed on each side, for a total of four positions. On the other hand, a lid 1 provided with four holes 2 engaging with the upper protrusions 4 is provided on a brim 8 which is formed by bending both ends of the flat plate along the inner side of the case body 3 so that the tips are opened upward. The upper protrusion 4 is inserted into the hole 2 by covering it with the side, and the lid 1 and the case body 3 are fixed. FIG. 2 shows a box type noise filter using the box type noise filter case of the present invention in which the assembly is completed and the lid 1 and the case body 3 are fixed. In FIGS. 1 and 2, the lower protrusion determines the depth at which the lid is attached to the inside of the case body when the lid is attached to the case body, and the upper protrusion 4 and the hole 2 of the lid 1 define the case body 3 And the lid 1 are fitted together. In the embodiment of the present invention, four upper protrusions and four lower protrusions are provided, but in the case body and lid of a large box noise filter, many upper protrusions 4 and lower protrusions 5 are provided. The provided lid 1 and the case body 3 are fitted and fixed.

[0008]

[Effect of the device]

 As described above, the lower projection for positioning the lower surface of the lid according to the present invention and the case main body having the upper projection engaging with the hole formed in the collar of the lid are provided with an upper lid that is elastic and open to the case main body. The box type has the advantage that it can be easily fixed and the solder that was used to fix the case body and lid to each other is no longer necessary, eliminating the flow of solder to the filter circuit and facilitating assembly. It is now possible to provide a noise filter case.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a box type noise filter case according to the present invention.

FIG. 2 is a perspective view showing the external appearance of the box-type filter according to the present invention.

FIG. 3 is an exploded perspective view of a conventional box-type noise filter case.

FIG. 4 is an external perspective view of a conventional box-type noise filter.

[Explanation of symbols]

 1 lid 2 hole 3 case body 4 upper protrusion 5 lower protrusion 6 terminal 7 soldering portion 8 collar 10 noise filter circuit

Claims (1)

[Scope of utility model registration request] 1. A box type noise filter case comprising a case body and a lid made of an electrically conductive thin metal plate, which faces inward toward the upper portion of the case body and is aligned parallel to the lower surface on the side surface. Then, the lower side is higher than the side surface and the case main body is provided with a plurality of protrusions on both sides in upper and lower two steps, and both sides of the elastic flat plate are in contact with the inner wall of the case main body and the upper side opened is open. A lid is provided so that a lower surface of the case body is in contact with the lower projection of the case body and a hole is provided in the flange for engaging with the upper projection, and the lid is formed so as to be fitted and fixed to the case body. Box type noise filter case.