JP2013055090A - Electromagnetic wave shielding housing and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic wave shielding housing which is not easily disassembled and shields electromagnetic waves, and to provide a manufacturing method of the electromagnetic wave shielding housing.SOLUTION: An electromagnetic wave shielding housing 1 includes: a metal cup shaped case 2 having an opening 22; a metal cover 3 covering the opening 22; a snap-fit mechanism 4 which has an engaging protrusion part 40 disposed at one of the case 2 and the cover 3 and an engaged recess part 41 disposed at the other of the case 2 and the cover 3 and fixes the case 2 to the cover 3 by engaging the engaging protrusion part 40 with the engaged recess part 41; and an adhesion part 5 adhering the case 2 to the cover 3. The engaging protrusion part 40 engages with the engaged recess part 41 leaving permanent deformation occurring during the engagement.

Description

  The present invention relates to an electromagnetic wave shielding casing that accommodates, for example, a circuit board on which electronic components are mounted, and a method for manufacturing the same.

  Patent Document 1 discloses an electronic device including a lower case and an upper case. An engagement hole is formed in the side wall of the upper case. On the other hand, an engaging protrusion is formed on the side wall of the lower case. The lower case and the upper case are fixed by the engagement protrusion engaging with the engagement hole. A plurality of urging force generating portions project from the upper edge of the side wall of the lower case. When the lower case and the upper case are fixed, the urging force generator elastically contacts the lower surface of the upper bottom wall of the upper case. The urging force of the urging force generator acts in a direction that separates the lower case and the upper case. The urging force presses the lower end of the engagement protrusion against the lower edge of the engagement hole. Further, rattling between the lower case and the upper case is suppressed.

  The lower case and the upper case are both made of SUS304. For this reason, a magnetic shield is formed by the lower case and the upper case. Therefore, the mounting substrate inside the electronic device can be protected from magnetism. For example, unintentional erasure of information in the flash memory can be suppressed.

JP 2010-258042 A

  However, in the case of the electronic device described in Patent Document 1, the lower case and the upper case are fixed only by a so-called snap-fit mechanism using a claw fitting between the engagement protrusion and the engagement hole. When the lower case and the upper case are fixed using the snap-fit mechanism, the engagement protrusion needs to protrude through the hole edge (or ride up) of the engagement hole and protrude into the engagement hole. At this time, at least one of the engagement hole and the engagement protrusion needs to be elastically deformed.

  Here, if the lower case and the upper case are made of resin, the engagement holes and the engagement protrusions are easily elastically deformed. For this reason, an engagement protrusion can be firmly engaged with an engagement hole. However, the lower case and the upper case of the electronic device described in Patent Document 1 are both made of SUS304. For this reason, the lower case and the upper case are not easily elastically deformed and are easily plastically deformed. Therefore, permanent distortion tends to remain at the time of engagement, and it is difficult to firmly engage the engagement protrusion with the engagement hole. Therefore, the electronic device described in Patent Document 1 is easily disassembled.

  In Patent Document 1, there is no description regarding plastic deformation and permanent distortion of the lower case and the upper case. On the other hand, paragraph [0020] of Patent Document 1 describes that since the urging force generating portion is bent, that is, in an elastically deformed state, an urging force is generated to return to the original shape.

  It is thought that this is intended to elastically deform the urging force generating portion by reducing the thickness of the lower case and the upper case as much as possible and selecting a material of SUS304. The working accuracy of the upper case has to be considerably increased, which makes the manufacturing costs very high.

  The electromagnetic wave shielding casing and the manufacturing method thereof according to the present invention have been completed in view of the above problems. An object of the present invention is to provide an electromagnetic wave shielding casing that is difficult to decompose and shields electromagnetic waves, and a method for manufacturing the same.

  (1) In order to solve the above problem, an electromagnetic wave shielding casing of the present invention is made of a metal and has a bottomed cylindrical case having an opening, a metal and a cover that covers the opening, An engaging convex portion disposed on one of the case and the cover, and an engaged concave portion disposed on the other of the case and the cover, the engaging convex portion and the engaged concave portion A snap-fit mechanism that fixes the case and the cover by engaging with each other, and an electromagnetic wave shielding housing in which an electronic component is accommodated, and further comprising the case and the cover. It has an adhesive part to be bonded, and the engaging convex part and the engaged concave part are engaged with each other while leaving a permanent distortion generated at the time of engagement. Here, the “engaged recess” includes not only a bottomed recess but also a bottomless hole.

  The electromagnetic wave shielding casing of the present invention includes a metal case and a cover. Metal is a conductor. For this reason, at least one of the electric field shield that shields the electric field and the electromagnetic shield that shields the electric field and the magnetic field by the eddy current due to the magnetism of the electromagnetic wave flowing through the conductor can protect the electronic components inside the housing. it can. When the case and the cover are made of a magnetic material, the electronic components inside the housing can be protected by a magnetic field shield that shields the magnetic field.

  The metal case and cover have higher dimensional accuracy than the resin case and cover. That is, when the case and the cover are made of resin, molding defects such as “shrinkage” and “warp” are likely to occur during molding. In contrast, when the case and the cover are made of metal, molding defects such as “shrinkage” and “warp” are less likely to occur during molding. Thus, the metal case and cover have higher dimensional accuracy than the resin case and cover. Further, the metal case and cover have higher strength than the resin case and cover.

  Moreover, the electromagnetic wave shielding housing of the present invention allows permanent distortion to remain due to plastic deformation during engagement between the engaging convex portion and the engaged concave portion. Permanent distortion tends to remain, for example, around the engaging convex portion, the engaging convex portion, the engaged concave portion, and the engaged concave portion. If the permanent distortion remains, it is difficult to firmly engage the engaging convex portion and the engaged concave portion. Therefore, the case and the cover are easily disassembled.

  However, the electromagnetic wave shielding casing of the present invention includes not only a snap-fit mechanism but also an adhesive portion. For this reason, a case and a cover can be fixed firmly. That is, the case and the cover are difficult to disassemble. Further, the case and the cover can be temporarily assembled by the snap fit mechanism until the case and the cover are bonded by the bonding portion. For this reason, the fixing position of the case and the cover is difficult to shift.

  (2) Preferably, in the configuration of the above (1), the engaging convex portion is disposed on a side wall of the case, the engaged concave portion is disposed on a side wall of the cover, and the engaging convex portion is disposed on the side wall of the case. It is better to have a configuration in which a slit is disposed at least one of the periphery of the engaging convex portion and the periphery of the engaged concave portion on the side wall of the cover.

  According to this configuration, when the engaging convex portion and the engaged concave portion are engaged, the load is not easily transmitted between adjacent portions adjacent to each other via the slit. For this reason, when one adjacent part deform | transforms, the other adjacent part is hard to restrain the said deformation | transformation. Therefore, the engagement convex portion and the engagement concave portion can be easily engaged with each other regardless of the metal case and cover that are not easily elastically deformed.

  Further, according to this configuration, stress is likely to concentrate around the base in the longitudinal direction of the slit when the engaging convex portion and the engaged concave portion are engaged. For this reason, the periphery of the slit in the longitudinal direction tends to be locally deformed. Also in this point, the engaging convex portion and the engaged concave portion can be easily engaged.

  (3) Preferably, in the configuration of (1) or (2), the engaging convex portion is disposed on a side wall of the case, and the engaged concave portion is disposed on a side wall of the cover. The thickness of at least one of the periphery including the engaging projection on the side wall of the cover and the periphery including the engaged recess on the side wall of the cover is the thickness of the portion other than the periphery of the side wall of the case. It is better to have a configuration in which the thickness is thinner than the thickness of the portion other than the periphery of the side wall of the cover.

According to this configuration, at least one of the following (A) and (B) is secured.
(A) The thickness of the periphery including the engaging convex part in the side wall of the case is formed thinner than the thickness of the part other than the periphery of the side wall of the case.
(B) The thickness of the periphery including the engaged recess in the side wall of the cover is thinner than the thickness of the portion other than the periphery of the side wall of the cover.

  In the case of (A), the surrounding wall thickness including the engaging convex portion can be made thin enough to allow plastic deformation. In the case of (B), the surrounding wall thickness including the engaged recess can be made thin enough to allow plastic deformation.

  According to this configuration, stress tends to concentrate on the thin portion (in the case of (A), the periphery including the engaging convex portion. In the case of (B), the periphery including the engaged concave portion). For this reason, the said thin part tends to deform | transform locally. Therefore, the same effect as the structure provided with the slit can be obtained.

  Of course, you may provide the said slit and a thin part suitably combining in the case side and the cover side.

  (4) In order to solve the above-described problem, an electromagnetic wave shielding casing manufacturing method of the present invention is an electromagnetic shielding casing manufacturing method according to any one of the above (1) to (3), A part preparing step for preparing the cover and the snap-fit mechanism, and the case and the cover are fixed by the snap-fit mechanism in a state where the adhesive portion is interposed between the case and the cover. It has a temporary assembly process and a bonding process for bonding the case and the cover by the bonding section.

  According to the temporary assembly process of the manufacturing method of the electromagnetic wave shielding casing of the present invention, the case and the cover can be fixed in an unbonded state by the snap-fit mechanism. Further, according to the bonding step, the case and the cover can be fixed in an bonded state, that is, bonded by the bonding portion.

  As described above, the method for manufacturing an electromagnetic wave shielding casing according to the present invention temporarily fixes the case and the cover with a snap-fit mechanism (temporary assembly process), and forms an adhesive portion in this state (adhesion process). The case and the cover are assembled. According to the temporary assembly process of the manufacturing method of the electromagnetic wave shielding casing of the present invention, the fixing position between the case and the cover is difficult to shift. Moreover, according to the adhesion process of the manufacturing method of the electromagnetic wave shielding housing of the present invention, the case and the cover can be firmly fixed.

  ADVANTAGE OF THE INVENTION According to this invention, it is hard to decompose | disassemble and can provide the electromagnetic wave shielding housing | casing which can shield electromagnetic waves, and its manufacturing method.

It is a perspective view of the electromagnetic wave shielding housing of the first embodiment. It is a disassembled perspective view of the electromagnetic wave shielding housing. It is the III-III direction sectional drawing of FIG. FIG. 4 is an enlarged view in a frame IV of FIG. 3. It is sectional drawing of the snap fit mechanism vicinity in the pre-assembly process of the manufacturing method of the electromagnetic wave shielding housing | casing. It is sectional drawing of the snap fit mechanism vicinity in the latter stage of the temporary assembly process. It is sectional drawing of the snap fit mechanism vicinity of the electromagnetic wave shielding housing | casing of 2nd embodiment. It is a schematic diagram which shows the variation of a snap fitting mechanism.

  Hereinafter, embodiments of the electromagnetic wave shielding casing and the manufacturing method thereof according to the present invention will be described.

<First embodiment>
[Configuration of electromagnetic shielding case]
First, the configuration of the electromagnetic wave shielding casing of this embodiment will be described. In FIG. 1, the perspective view of the electromagnetic wave shielding housing | casing of this embodiment is shown. FIG. 2 is an exploded perspective view of the electromagnetic wave shielding casing. FIG. 3 shows a cross-sectional view in the III-III direction of FIG. FIG. 4 shows an enlarged view in the frame IV of FIG. In addition, in FIG. 4, the slit 35 is shown with a dashed-dotted line.

  As shown in FIGS. 1 to 4, the electromagnetic wave shielding housing 1 includes a case 2, a cover 3, a snap fit mechanism 4, and an adhesive portion 5.

  The case 2 is made of an aluminum alloy and has a bottomed cylindrical shape that opens upward. Case 2 is an integral object. The case 2 includes a bottom wall portion 20, four side wall portions 21, an opening portion 22, and a groove portion 23. The bottom wall portion 20 has a rectangular plate shape. The four side wall portions 21 protrude upward from the four edges of the bottom wall portion 20. The opening 22 is disposed on the upper edge of the four side wall portions 21. The opening 22 has a rectangular frame shape. The groove 23 is recessed in the opening 22. The groove 23 is arranged in a rectangular ring shape along the opening 22. Inside the case 2, a circuit board 90 on which electronic components are mounted is disposed.

  The cover 3 is made of an aluminum alloy and has a bottomed cylindrical shape that opens downward. The cover 3 is a single piece. The cover 3 covers the case 2 from above and from the outside in the horizontal direction.

  The cover 3 includes an upper bottom wall portion 30, four side wall portions 31, an opening portion 32, a rib 33, a guide portion 34, and a total of eight slits 35. The upper bottom wall portion 30 has a rectangular plate shape. The upper bottom wall portion 30 faces the bottom wall portion 20 of the case 2 in the vertical direction. The four side wall portions 31 protrude downward from the four edges of the upper bottom wall portion 30. The four side wall portions 31 are disposed outside the four side wall portions 21 of the case 2 in the horizontal direction. The opening 32 is disposed at the lower edge of the four side wall portions 31. The opening 32 has a rectangular frame shape. The rib 33 protrudes from the lower surface of the upper bottom wall portion 30. The ribs 33 are arranged in a rectangular ring shape along the outer edge of the upper bottom wall portion 30. The rib 33 is accommodated in the groove 23 of the case 2. The guide part 34 is disposed inside the opening part 32 in the horizontal direction. The guide portion 34 is arranged in a rectangular ring shape along the opening portion 32. The guide portion 34 has a slope shape that inclines inward in the horizontal direction when going from the bottom to the top. A total of eight slits 35 are arranged on the two side wall portions 31 at the front and rear, respectively. The slit 35 opens at the lower end (that is, the opening 32) of the side wall 31. The slit 35 extends in the vertical direction. On the front side wall portion 31, a deforming portion 310 is arranged by being partitioned by a pair of left and right slits 35. Two deforming portions 310 are arranged apart from each other in the left-right direction. Similarly, two two deforming portions 310 are also arranged on the rear side wall portion 31.

  The adhesive portion 5 is obtained by curing an epoxy or acrylic adhesive. The bonding portion 5 is interposed between the groove portion 23 of the case 2 and the rib 33 of the cover 3. The case 2 (opening 22) and the cover 3 (upper bottom wall 30) are bonded by the bonding portion 5. Further, the bonding portion 5 suppresses the generation of a gap between the case 2 and the cover 3.

  The snap fit mechanism 4 includes a total of four engagement convex portions 40 and a total of four engaged holes 41. The engaged hole 41 is included in the concept of the “engaged recess” of the present invention. A total of four engaged holes 41 are arranged on the two side wall portions 31 on the front and rear sides of the cover 3 two by two. Specifically, the engaged hole 41 is disposed in the deformable portion 310. The engaged hole 41 penetrates the deformable portion 310 in the horizontal direction. The cross section in the direction perpendicular to the hole axis of the engaged hole 41 has a rectangular shape.

  A total of four engaging projections 40 are provided so as to protrude from the outer surface of the two side wall portions 21 of the front and rear of the case 2. The engaging convex portion 40 is inserted into the engaged hole 41 from the inner side in the horizontal direction. The engaging convex part 40 and the to-be-engaged hole 41 are engaged in the up-down direction.

[Method of manufacturing electromagnetic shielding casing]
Next, the manufacturing method of the electromagnetic wave shielding housing of this embodiment will be described. The manufacturing method of the electromagnetic wave shielding casing of the present embodiment includes a component preparation process, a temporary assembly process, and an adhesion process.

  In the component preparation step, first, the case 2 and the cover 3 are produced by die casting. Further, an engaged hole 41 is formed in the cover 3. Further, the engaging convex portion 40 is formed on the case 2. The engaged holes 41 and the engaging protrusions 40 are formed by machining such as cutting after the case 2 and the cover 3 are formed by die casting. From the beginning, the engaged holes 41 and the engaging protrusions 40 are formed by die casting. The part 40 can also be formed. Next, the groove 23 of the case 2 is filled with a liquid adhesive. Note that the adhesive portion 5 is obtained by curing the adhesive.

  FIG. 5 shows a cross-sectional view of the vicinity of the snap-fit mechanism in the pre-stage of the temporary assembly process of the method for manufacturing an electromagnetic wave shielding casing of the present embodiment. FIG. 6 shows a cross-sectional view of the vicinity of the snap-fit mechanism in the latter stage of the temporary assembly process. 5 and 6 correspond to FIG.

  In the temporary assembly process, first, the circuit board 90 is mounted inside the case 2. Next, as shown in FIG. 5, the cover 3 is brought relatively close to the case 2 so as to cover the opening 22 of the case 2. When the opening 32 of the cover 3 is close to the opening 22 of the case 2, the guide portion 34 is in sliding contact with the outer edge of the opening 22. For this reason, the cover 3 is guided to the outside in the horizontal direction of the case 2 without the opening 32 of the cover 3 hitting the opening 22 of the case 2. Subsequently, the inner surface of the side wall portion 31 of the cover 3 slides on the outer surface of the side wall portion 21 of the case 2. Then, the guide part 34 reaches the engaging convex part 40. As shown in FIG. 6, when the guide portion 34 comes into contact with the upper end portion of the engaging convex portion 40, a load on the outer side in the horizontal direction (frontward in FIG. 6) acts on the guide portion 34, that is, the deformed portion 310.

  Here, as shown in FIGS. 1 and 2, a pair of slits 35 are arranged on the left and right sides of the deformable portion 310. That is, the gap between the deformable portion 310 and the portion of the side wall portion 31 adjacent to the deformable portion 310 is blocked by the slit 35. For this reason, the deformation of the deformation portion 310 is not restricted at all by the portion of the side wall portion 31 adjacent to the deformation portion 310.

  Therefore, as shown by a white arrow in FIG. 6, the deforming portion 310 swings forward around the base in the longitudinal direction of the slit 35. Due to the swinging, the portion of the deformable portion 310 below the engaged hole 41 gets over the engaging convex portion 40 relatively. Here, the deforming portion 310 accumulates an elastic force that moves backward by rocking forward. For this reason, when the engaged hole 41 reaches the engaging convex portion 40 due to the elastic force, the deformable portion 310 swings backward around the longitudinal root of the slit 35. Due to the swinging, the engaging convex portion 40 is relatively engaged with the engaged hole 41.

  In addition, when the engaging convex portion 40 is relatively engaged with the engaged hole 41, the rib 33 of the cover 3 enters the groove portion 23 of the case 2. For this reason, a zigzag gap is defined between the rib 33 and the groove 23. The liquid adhesive 5a shown in FIG. 6 flows into the gap.

  Thus, in the temporary assembly step, the case 2 and the cover 3 are fixed by engaging the engagement convex portion 40 of the snap fit mechanism 4 with the engaged hole 41. Further, the liquid adhesive 5a shown in FIG. 6 is caused to flow into the zigzag gap between the rib 33 and the groove 23.

  In the bonding step, as shown in FIGS. 6 and 4, the liquid adhesive 5 a is cured in a zigzag gap between the rib 33 and the groove 23. Then, a solid adhesive portion 5 is formed. That is, the gap is sealed around the entire circumference by the bonding portion 5. In addition, the case 2 and the cover 3 are firmly bonded.

[Function and effect]
Next, the effect of the electromagnetic wave shielding casing and the manufacturing method thereof according to the present embodiment will be described. The electromagnetic wave shielding casing 1 of this embodiment includes a case 2 and a cover 3 made of aluminum alloy. For this reason, the circuit board 90 inside the housing is protected by at least one of an electric field shield that shields the electric field and an electromagnetic shield that shields the electric field and the magnetic field by the eddy current due to the magnetism of the electromagnetic wave flowing through the conductor. Can do.

  The aluminum alloy case 2 and the cover 3 have higher dimensional accuracy than the resin case 2 and the cover 3. That is, when the case 2 and the cover 3 are made of resin, molding defects such as “shrunk” and “warp” are likely to occur during molding. On the other hand, when the case 2 and the cover 3 are made of an aluminum alloy, molding defects such as “shrinkage” and “warp” hardly occur during molding. Thus, the aluminum alloy case 2 and the cover 3 have higher dimensional accuracy than the resin case 2 and the cover 3. The aluminum alloy case 2 and the cover 3 are higher in strength than the resin case 2 and the cover 3.

  Further, the electromagnetic wave shielding casing 1 of the present embodiment allows permanent distortion to remain due to plastic deformation during engagement of the engaging convex portion 40 and the engaged hole 41. That is, as shown in FIG. 4, permanent deformation remains in the deformable portion 310 by an angle θ with respect to a state in which the deformed portion 310 is moved back elastically (shown by a dotted line in FIG. 4). If the permanent distortion remains, it is difficult to firmly engage the engagement convex portion 40 and the engaged hole 41. Therefore, the case 2 and the cover 3 are easily disassembled.

  However, the electromagnetic wave shielding casing 1 of the present embodiment includes not only the snap fit mechanism 4 but also the adhesive portion 5. For this reason, the case 2 and the cover 3 can be firmly fixed. That is, the case 2 and the cover 3 are difficult to disassemble. Further, the case 2 and the cover 3 can be temporarily assembled by the snap-fit mechanism 4 until the case 2 and the cover 3 are bonded by the bonding portion. For this reason, the fixing position of case 2 and cover 3 is hard to shift.

  Further, according to the electromagnetic wave shielding casing 1 of the present embodiment, as shown in FIGS. 1 and 2, a pair of slits 35 extending in the vertical direction are disposed on the left and right sides of the engaged hole 41. For this reason, the deformation | transformation part 310 tends to deform | transform. Therefore, despite the case 2 and the cover 3 made of aluminum alloy that are not easily elastically deformed, the engaging convex portion 40 and the engaged hole 41 can be easily engaged.

  Further, according to the electromagnetic wave shielding casing 1 of the present embodiment, stress is likely to be concentrated around the upper end of the slit 35 (near the upper end of the deforming portion 310) when the engaging convex portion 40 and the engaged hole 41 are engaged. . For this reason, the periphery of the upper end of the slit 35 (near the upper end of the deformation portion 310) is likely to be locally deformed. Also in this respect, the engaging convex portion 40 and the engaged hole 41 can be easily engaged.

  Further, according to the electromagnetic wave shielding housing 1 of the present embodiment, the slit 35 is disposed only in the cover 3, and the slit 35 is not disposed in the case 2. For this reason, at the time of assembling the electromagnetic wave shielding housing 1, the deformed portion 310 of the cover 3 is deformed on the initiative rather than the side wall portion 21 of the case 2. Therefore, the permanent distortion hardly remains in the case 2 after the assembly of the electromagnetic wave shielding casing 1. Therefore, the volume inside the case 2 is difficult to change. In addition, it is difficult for the circuit board 90 inside the case 2 to be subjected to a load due to permanent distortion. In addition, permanent distortion hardly remains in portions other than the deformed portion 310 of the cover 3.

  Further, according to the electromagnetic wave shielding casing 1 of the present embodiment, a zigzag gap is defined between the rib 33 and the groove 23 as shown in FIG. An adhesive portion 5 is disposed in the gap. For this reason, the adhesion part 5 extends redundantly in a zigzag shape. Therefore, compared with the case where the adhesion part 5 is extended linearly, gas, a liquid, a foreign material, dust, etc. cannot enter the case 2 from the outside through a gap. Thus, the electromagnetic wave shielding casing 1 of the present embodiment has high sealing performance.

  Further, according to the electromagnetic wave shielding casing 1 of the present embodiment, as shown in FIG. 4, the ribs 33 are accommodated in the grooves 23 in the vertical direction. For this reason, the side wall part 21 is hard to fall down in the horizontal direction.

  Further, according to the electromagnetic wave shielding casing 1 of the present embodiment, as shown in FIGS. 5 and 6, when engaging the engaging convex portion 40 and the engaged hole 41, the guide portion 34 is an opening of the case 2. The portion 22 is in sliding contact. For this reason, it is easy to externally fit the cover 3 to the case 2. Further, when engaging the engaging convex portion 40 with the engaged hole 41, the guide portion 34 is in sliding contact with the engaging convex portion 40. For this reason, the lower part of the deformation part 310 can easily get over the engagement convex part 40.

  Moreover, the manufacturing method of the electromagnetic wave shielding housing 1 of the present embodiment includes a temporary assembly process and an adhesion process. According to the temporary assembly process, the case 2 and the cover 3 can be fixed in a non-adhered state by the snap-fit mechanism 4. Further, according to the bonding process, the case 2 and the cover 3 can be fixed in an adhesive state, that is, bonded by the bonding portion 5.

  As described above, in the method of manufacturing the electromagnetic wave shielding casing 1 according to this embodiment, the case 2 and the cover 3 are temporarily fixed by the snap-fit mechanism 4 (temporary assembly process), and the adhesive 5a is cured in this state. By forming the adhesion part 5 (adhesion process), the case 2 and the cover 3 are firmly fixed. According to the manufacturing method of the electromagnetic wave shielding casing 1 of the present embodiment, the temporary fixing position between the case 2 and the cover 3 is difficult to shift when the adhesive 5a is cured. For this reason, the case 2 and the cover 3 can be firmly fixed by the bonding portion 5.

<Second embodiment>
The difference between the electromagnetic shielding case and the manufacturing method thereof of the present embodiment and the electromagnetic shielding case and the manufacturing method of the first embodiment is that the engaging convex portion is the cover and the engaged concave portion is the case. It is a point that is arranged. Here, only differences will be described.

  In FIG. 7, sectional drawing of the snap fit mechanism vicinity of the electromagnetic wave shielding housing | casing of this embodiment is shown. In addition, about the site | part corresponding to FIG. 4, it shows with the same code | symbol. As shown in FIG. 7, the engaging convex portion 40 protrudes from the inner surface in the horizontal direction of the deformable portion 310 of the side wall portion 31 of the cover 3. Further, the engaged recess 42 is provided in the horizontal outer surface of the side wall 21 of the case 2.

  The electromagnetic wave shielding casing and the manufacturing method thereof according to the present embodiment and the electromagnetic wave shielding casing and the manufacturing method according to the first embodiment have the same functions and effects with respect to parts having common configurations. According to the electromagnetic wave shielding casing of the present embodiment, the engaged recess 42 is covered by the side wall portion 31 from the outside in the horizontal direction. For this reason, it is hard to interfere with the snap fit mechanism 4 of the electromagnetic shielding case after assembly from the outside. Therefore, the electromagnetic wave shielding housing is difficult to disassemble. The engaged recess 42 is bottomed. For this reason, gas, liquid, foreign matter, dust or the like does not enter the case 2 from the outside via the engaged recess 42.

<Others>
The embodiment of the electromagnetic wave shielding casing and the manufacturing method thereof according to the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. Various modifications and improvements that can be made by those skilled in the art are also possible.

  FIG. 8 schematically shows a variation of the snap fit mechanism. In addition, about the site | part corresponding to FIG. 4, FIG. 7, it shows with the same code | symbol. As shown in FIG. 8A, the engagement convex portion 40 may be conical. Further, the cross section of the engaged recess 42 may be conical. As shown in FIG. 8B, the engagement convex portion 40 may be a partial spherical shape. As shown in FIG. 8C, the engaging convex portion 40 may be formed by stamping from the inner surface of the side wall portion 21 by press molding.

  The material of the case 2 and the cover 3 is not particularly limited. In the case of a non-magnetic material such as austenitic stainless steel, aluminum, copper, and brass, as in the above embodiment, an electric field shield that shields the electric field, and an eddy current due to magnetism of electromagnetic waves flows through the conductor, thereby The circuit board 90 inside the housing can be protected by at least one of the electromagnetic shields that shields.

  In the case of magnetic material such as nickel, iron, cobalt, gadolinium, austenitic / ferritic stainless steel, ferritic stainless steel, martensitic stainless steel, precipitation hardened stainless steel, The circuit board 90 inside the housing can be protected.

  The method for forming the case 2 and the cover 3 is not particularly limited. For example, it can be produced by a method such as die casting, forging or cutting.

  Moreover, the position, the number of arrangement | positioning, and magnitude | size of (engagement convex part 40-to-be-engaged hole 41) group are not specifically limited. For example, what is necessary is just to arrange | position in the position (FIG. 1 demonstrates) the front side wall part 31 and the back side wall part 31, or the left side wall part 31 and the right side wall part 31 which oppose each other. Moreover, the position, the number of arrangement | positioning, and length of the slit 35 are not specifically limited.

  In addition, the position, the number of arrangement, and the type of the bonding portion 5 are not particularly limited. For example, the adhesive portion 5 may be disposed between the outer surface of the adjacent side wall portions 21 and the inner surface of the side wall portion 31. The adhesive 5a for the bonding part 5 may be in the form of gel or clay in addition to liquid. A double-sided tape may be disposed as the bonding portion 5.

  Moreover, you may arrange | position a positioning pin in one side among the bottom wall part 20 of case 2, and the upper bottom wall part 30 of the cover 3, and a pin insertion hole in the other, respectively. If it carries out like this, position alignment with case 2 and the cover 3 can be performed by inserting a positioning pin in a pin insertion hole in a temporary assembly process.

  Moreover, the use of the electromagnetic wave shielding casing 1 is not particularly limited. For example, it can be used as a casing of an ECU (engine control unit) of a vehicle, a casing of a hard disk of a computer, or the like.

1: Electromagnetic wave shielding housing, 2: Case, 3: Cover, 4: Snap fit mechanism, 5: Adhesive part, 5a: Adhesive.
20: bottom wall part, 21: side wall part, 22: opening part, 23: groove part, 30: upper bottom wall part, 31: side wall part, 32: opening part, 33: rib, 34: guide part, 35: slit, 40: engaging convex part, 41: engaged hole (engaged recessed part), 42: engaged recessed part, 90: circuit board, 310: deformed part.

Claims (4)

A bottomed cylindrical case made of metal and having an opening,
A cover made of metal and covering the opening;
An engaging convex portion disposed on one of the case and the cover, and an engaged concave portion disposed on the other of the case and the cover, the engaging convex portion and the engaged portion A snap-fit mechanism for fixing the case and the cover by engaging the recess;
An electromagnetic shielding housing in which electronic components are housed,
Furthermore, an adhesive part for adhering the case and the cover is provided,
The electromagnetic wave shielding housing, wherein the engaging convex portion and the engaged concave portion are engaged with each other while leaving a permanent distortion generated at the time of engagement. The engaging protrusion is disposed on a side wall of the case,
The engaged recess is disposed on a side wall of the cover;
The electromagnetic wave shielding housing according to claim 1, wherein a slit is disposed at least on one of a periphery of the engaging convex portion on the side wall of the case and a periphery of the engaging concave portion on the side wall of the cover. The engaging protrusion is disposed on a side wall of the case,
The engaged recess is disposed on a side wall of the cover;
The thickness of at least one of the periphery including the engaging protrusion on the side wall of the case and the periphery including the engaged recess on the side wall of the cover is a portion other than the periphery of the side wall of the case The electromagnetic shielding casing according to claim 1 or 2, wherein the electromagnetic shielding casing is formed thinner than a thickness of the cover or a thickness of a portion other than the periphery of the side wall of the cover. It is a manufacturing method of the electromagnetic wave shielding case according to any one of claims 1 to 3,
A component preparation step of preparing the case, the cover, and the snap-fit mechanism;
A temporary assembly step of fixing the case and the cover by the snap-fit mechanism in a state where the adhesive portion is interposed between the case and the cover;
A bonding step of bonding the case and the cover by the bonding portion;
The manufacturing method of the electromagnetic wave shielding housing | casing which has this.

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