JPH10326988A - Attaching structure of electronic components - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability of the performance of an electromagnetic shield, by improving the easiness of assembling reducing the number of components and equalizing the contacting clamp pressure among each of members. SOLUTION: In storing a printed circuit board 20 electromagnetically shielded inside a shielded case 10 tightly covered with a shield cover 30, the shield case 10 is provided with a ground contacting surfaces 12 of a frame form along the peripherals of a case main body 11, and cover inserting grooves 15 with the cross sections of recessed form arranged to a pair of the outer parts of the side walls of the case main body 11. A case cover 30 is formed by bending inward an inserting part 32 latching the cover inserting grooves 15 of the case main body 11 and sliding through it. A grounding panel 40 has a flat plate form of a similar size and can be assembled on the inner side of the case cover 30, ground contacting flanges 42 are formed by bending inward it along each of the peripherals of it, and the crest parts formed by bending the ground contacting flanges 42 are brought on line contact with the ground contacting surface 12 on the upper surface of the case main body 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure in which electronic components such as a printed circuit board are shielded by electromagnetic waves and housed in a housing case, particularly in a wireless communication device.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional example of this type of mounting structure. The device housing in the radio section includes a shield case 1 and a shield cover 2 for storing the internally mounted components in a state where the components are shielded from electromagnetic waves. For example, a printed circuit board 3 as a component to be shielded and a flat ground having substantially the same shape as this. The panel 4 is stored.

[0005] The printed circuit board 3 includes a plurality of mounting bolts 5.
By this, it is fastened and fixed to the shield case 1. The mounting bolt 5 has a male screw portion 5b formed continuously with one end of a head portion 5a having a hexagonal cross section, and a female screw portion 5c is formed in the head portion 5a.

Accordingly, as shown in an assembly sectional view of FIG. 6, the printed circuit board 3 is first fastened and fixed to the shield case 1 by such mounting bolts 5. After fixing the board, the female screw 5c of the head 5a protruding from the upper surface of the printed board 3
The shield cover 2 and the ground plate 4 inside the shield cover 2 are fixed to the shield case 1 and closed by screwing the cover set screw 6 directly into the shield case 1.

[0005]

The conventional mounting structure shown in FIGS. 5 and 6 has the following problems to be solved.

One problem is that the number of parts is complicated and diversified, and there is a problem that the manufacturing cost including the parts cost and the number of assembly steps rises.

One is a structure in which a flat flexible grounding panel 4 is interposed between the printed circuit board 3 and the inside of the shield cover 2, so that the shield cover 2 rises due to its elasticity. As a result, positioning during assembly is difficult. In addition, there is a problem that the contact pressure with respect to the shield case 1 cannot be maintained uniformly due to its elasticity. That is, at the time of fastening with the mounting bolt 5 and the cover set screw 6, depending on the level of the tightening force of these two fastening members, the torque balance is lost and the contact pressure between the periphery of the fastening part and the fastening part becomes uneven. .

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a mounting structure for accommodating electronic parts such as a printed circuit board in an equipment casing by shielding them from electromagnetic waves. It is an object of the present invention to provide an electronic component mounting structure that can realize a uniform and uniform contact fastening pressure between members, thereby improving the reliability of electromagnetic wave shielding.

[0009]

SUMMARY OF THE INVENTION The electronic component mounting structure according to the present invention is designed so that when a printed circuit board, which is a flat electronic component, is housed in an electromagnetic wave shielded manner, the printed circuit board extends along the edge of a planar rectangular case body. A housing case having a frame-shaped ground contact surface formed therein and having cover insertion grooves each having a concave cross section on two outer sides of the opposing side walls of the case main body; and closing the case main body from a planar direction. It is a flat plate shape of almost the same size as possible, and an insertion portion which is slidable from one side into the cover insertion groove of the housing case along two opposing edges of the edge is provided by being bent inward. A case cover in which the mounting flange is bent inward along the other two opposing edges perpendicular to the insertion portion, and a plate of substantially the same size that can be assembled inside the case cover, A grounding flange which is bent inward along the edge to provide a grounding flange, and the grounding flange is formed so as to be in line contact with each of the frame-shaped grounding contact surfaces of the housing case. .

In this case, the grounding flange can be linearly contacted over substantially the entire length of one side of the frame-shaped ground contact surface on the mountain fold side of the bending, and the mountain fold side of the bending is the ground contact side. It has a spring shape that can elastically contact the surface.

[0011] Therefore, assembling electronic components such as a printed circuit board, a case cover, and a grounding panel for electromagnetic wave shielding to the housing case is based on insertion. Therefore, the number of parts is reduced, and the assembling work is reduced accordingly.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As a preferred embodiment of an electronic component mounting structure according to the present invention, a case of a printed circuit board used for a wireless communication device will be described in detail with reference to the drawings.

FIG. 1 is an exploded perspective view of a radio unit constituting a part of a high-density mounting unit for mounting a printed circuit board 20 by shielding electromagnetic waves. In other words, the shield cover 30 of the case cover according to the present invention includes the shield case 10 of the housing case according to the present invention for mounting the printed circuit board 20 in an electromagnetic wave shield and sealing the printed circuit board 20 after mounting. Is fastened to the shield case 10 and fastened together with the grounding panel 40 incorporated therein.

The shield case 10 has a case main body 11 formed in a planar rectangular shape, and a ground contact surface 12 is formed along the edge of the case main body 11 in a frame shape. A stepped portion 13 which is lower by one step is provided along the inside of the frame-shaped ground contact surface 12, and the frame-shaped stepped portion 13 is capable of receiving and supporting the printed circuit board 20 from above in the vertical direction. The stepped portion 13 is provided with a plurality of tap screws 14 for mounting the board using female threads, and the printed board 20 is fastened and fixed with the mounting screws 23 with the tap screws 14.

Further, the case body 1 of the shield case 10
1 is provided with a cover insertion groove 15 having a concave cross section over the entire external length of the two side walls facing back to back. That is, the shield cover 30 can be slid into the pair of parallel cover insertion grooves 15 on both sides by guiding the shield cover 30 from the groove ends, and the insertion allows the shield cover 30 to be temporarily assembled to the case body 11.

The printed circuit board 20 includes a main body 2.
Around the flat plate 1, mounting holes 22 are formed by the same number of through-holes (commonly called stupid holes) or tap screws at the same positions as the tap screws 14 provided on the shield case 10 side.
Fixed by

On the other hand, in the shield cover 30, an insertion portion 32 having a U-shaped cross section is provided along two opposing edges of the flat main body 31 by being bent inward. The pair of opposed insertion portions 32 are connected to the shield case 1.
By engaging with the cover guide groove 15 provided on the 0 side, the shield cover 30 can be temporarily assembled to the shield case 10 and set. In addition, a panel mounting flange 33 is provided by being bent inward along another opposing edge of the main body 31 orthogonal to the pair of opposing insertion portions 32. A grounding panel 40 is fastened to the inside of the panel mounting flange 33 and can be fixed to the shield case 10. The earth mounting flange 33 is provided with several mounting holes 34, and the mounting screws 35 are connected to the mounting holes 34.
And fastened together with the inner ground panel 40. Therefore, in this case, the case body 1 of the shield case 10
One side wall 16 is provided with a mounting screw hole 17 for final tightening of the cover.

In the grounding panel 40, as shown in FIGS. 4 (a) and 4 (b) which are single parts, two opposing grounding flanges 42 bent inward along four edges of the flat plate. And two opposing grounding flanges 44 are provided. These grounding flanges 42 and 44 are formed into a cross-sectional shape that makes line contact with the frame-shaped ground contact surface 12 on the shield case 10 side at the mountain-folded portions 42a and 44a and that can be contacted with spring-like elasticity. The pair of grounding flanges 42 on one side also serve as mounting flanges, and the panel mounting flange 33 on the shield cover 30 side.
And a mounting hole 43 for fastening with the mounting screw 35 is formed.

With the above-described components, assembly is performed as in the following example. First, the printed circuit board 20 is fixed in the shield case 10 by the mounting screw 23.

On the other hand, on the shield cover 30 side, a ground panel 40 is incorporated inside.

As shown in FIG. 3, the shield cover 30 in which the grounding panel 40 is incorporated is guided by the insertion portions 32 on both sides into the pair of cover insertion grooves 15 on the shield case 10 side and slid. Then, the temporary assembly is completed.

Next, the mounting screw 35 is screwed into the mounting hole 34 of the panel mounting flange 33 with respect to the shield cover 30 temporarily assembled in the shield case 10 and closed, so that the grounding flange 42 of the inner grounding panel 40 is formed. Screw it into the mounting hole 43 as well. Thus, the panel mounting flange 33 of the shield cover 30 and the grounding flange 42 of the grounding panel 40
Are the mounting screw holes 17 in the side wall 16 in the case body 11.
Will be tightened together. That is, the shield cover 30 and the grounding panel 40 are fixed to the shield case 10 by screw tightening.

In such an assembly, each of the mountain-folded portions 42a, 44a of the grounding flanges 42, 44 of the grounding panel 40 is in a planar shape as in the prior art with respect to the grounding contact surface 12 on the upper surface of the frame on the shield case 10 side. But not in a line. By such a linear contact, the shield cover 30 can be easily and uniformly connected to the shield case 10.

[0024]

As described above, the mounting structure of the electronic component according to the present invention is not limited to the housing case, the case cover for closing the housing case, and the structure in which the flat electronic component such as the printed board is housed therein. Therefore, in the structure related to the electromagnetic wave shield, when a flat panel for grounding is mounted inside the cover, the components are inserted into each other. Points are reduced,
It is very advantageous in terms of cost.

Further, the disadvantage that the ground panel mounted for electromagnetic wave shielding is brought into contact with the housing case as in the prior art by floating contact can be eliminated by line contact and elastic contact. On the other hand, there is an effect that the assemblability of the case cover is significantly improved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an electronic component mounting structure according to the present invention.

FIG. 2 is a side cross-sectional view showing a form in which a shield cover is inserted into a shield case, which is a main part of the present embodiment.

FIG. 3 is a partially sectional front view showing an operation of inserting a shield cover into the shield case.

FIGS. 4 (a) and 4 (b) are views taken along lines AA and B-B in FIG.
It is each sectional drawing of the grounding panel by the B line.

FIG. 5 is an exploded perspective view showing a conventional mounting structure.

FIG. 6 is a partially sectional view of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Shield case (casing case) 11 Case main body 12 Ground contact surface 15 Cover insertion groove 17 Cover joint fastening mounting hole 20 Printed circuit board (flat electronic component) 23 Board mounting screw 30 Shield cover (case cover) 32 Insert Part 33 Panel mounting flange 40 Grounding panel 42, 44 Grounding flange 42a, 44a Mountain fold part that makes line contact

Claims (5)

[Claims] 1. A frame-shaped ground contact surface formed along an edge of a planar rectangular case main body for accommodating a flat electronic component, and two framed opposing side walls of the case main body. A housing case provided with a cover insertion groove having a concave cross-section, and a flat plate of substantially the same size capable of closing the case body from a planar direction, and along the two opposing edges of the housing case, A case cover in which an insertion portion that can be engaged by sliding into the cover insertion groove from one side is bent inward, and a plate of approximately the same size that can be assembled inside the case cover, A grounding flange is provided by being bent inward along the line, and the grounding flange is formed so as to be in line contact with each of the frame-shaped ground contact surfaces of the housing case. Mounting structure of an electronic component, characterized. 2. The grounding flange according to claim 1, wherein each of said grounding flanges has a shape capable of linearly contacting substantially the entire length of a corresponding side of said frame-shaped grounding contact surface on the mountain-folding side of the bending. 2. The mounting structure of the electronic component according to 1. 3. The mounting of an electronic component according to claim 1, wherein each of the grounding flanges has a spring shape such that a mountain-folding side of the bending can elastically contact the corresponding ground contact surface. Construction. 4. The mounting of an electronic component according to claim 1, wherein the case cover is coupled to the side wall of the case body by fastening together with the inner ground panel. Construction. 5. The electronic device according to claim 1, wherein said housing case and said case cover closing said housing enable electromagnetic wave shielding, and said electronic component mounted inside is a printed circuit board. The mounting structure of the electronic component according to 1.