JPH07326882A - Shielding case - Google Patents

Abstract

PURPOSE:To provide a shielding case which is low in cost and capable of accurately positioning and fixing a printed board. CONSTITUTION:A shielding case which houses a printed board mounted with electronic parts is equipped with a case main body 4, wherein a U-shaped frame 1 and a pair of lids 2 and 3 are assembled into the case main body 4 of integral structure and possessed of an open side 5 which serves as a board insertion opening 5. Board insertion guides 6 extending inwards respectively are provided to the frame 1 of the case main body 4 at several spots, and the printed boards are joined to the guides 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield case used for housing a printed circuit board on which electronic parts are mounted.

[0002]

2. Description of the Related Art Generally, many of module components (for example, electronic tuners) incorporated in home TVs and VTRs house a printed circuit board on which various electronic components are mounted in a shield case to generate an external magnetic field or an external electric field. It is shielded from the influence of. The shield case has a square box structure, and tinplate is often used as the material.

In a conventional shield case, a box-shaped frame body and a pair of lid bodies are assembled together to form a box-shaped case body, and a printed circuit board is housed inside the case body. Further, a stator is integrally provided on the case body, and by inserting the terminals of the printed circuit board together with the stator into the mother board, the entire case including the printed circuit board is supported by the mother board. It was

[0004]

However, in the conventional shield case, the frame body constituting the case body and the pair of lid bodies have separate structures, that is, so-called 3
Because of the peace structure, there were the following problems. (1) Since the mold for molding the frame and the mold for molding the lid are separately required, the equipment cost (initial cost) is high and the case cost is high. Furthermore, since it is necessary to assemble the frame body and the lid body, which are molded by separate molds, into one body, it takes time to assemble the case. (2) Since the substrate cannot be attached after the lid is attached to the frame, the substrate is inevitably attached with the frame alone. However, since the rigidity of the frame body is extremely low, it is difficult to accurately position the printed circuit board due to deformation of the frame body or wobbling of the board. Therefore, relative displacement occurs between the stator of the shield case and the terminals of the printed circuit board, and even if the shield case is attached to the mother board, the terminals of the printed circuit board may be caught on the mother board. I was invited.

The present invention has been made to solve the above problems, and an object thereof is to provide a shield case which is inexpensive and can position and fix a printed circuit board with high accuracy.

[0006]

The present invention has been made to achieve the above object, and in a shield case for accommodating a printed circuit board on which electronic components are mounted, a U-shaped frame and a pair of lids. A case body is integrally formed in a box shape while opening one side by and the opening portion is used as a substrate insertion port. The frame body of the case main body is provided with a plurality of guide portions for inserting the board in a state of protruding inward, and the printed board can be joined to the guide portions.

[0007]

In the shield case of the present invention, since the case body is integrally molded in a box shape by the U-shaped frame body and the pair of lid bodies, only one type of die is required for manufacturing the case body. Become. Further, when mounting the printed circuit board, the printed circuit board is inserted into the case body integrally formed in the box shape through the board insertion port. At that time, the insertion position of the printed circuit board is regulated by the guide portion, and the printed circuit board is joined to the guide portion under the regulated state.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a diagram for explaining an embodiment of a shield case according to the present invention, and FIG. 2 is a development view thereof. As shown in the figure, in the shield case of the present embodiment, the case body 4 is integrally formed in a box shape by the frame body 1 having a U-shape and the pair of lid bodies 2 and 3. The case body 4 has one opening corresponding to the outer diameter of a printed circuit board (not shown), and the opening portion is provided with a board insertion port 5
I am trying.

The frame body 1 of the case body 4 is provided with a plurality of guide portions 6 for inserting a substrate at four locations (four locations in the illustrated example). These guide portions 6 are formed in a bow shape, for example, as shown in the drawing, with a part of the frame 1 protruding inward. Furthermore, the individual guide portions 6 are
It is composed of a pair of guide pieces 6a, 6b, and a gap corresponding to the thickness dimension of a printed circuit board (not shown) is secured between these guide pieces 6a, 6b. The shape of the guide pieces 6a and 6b is not limited to the above-mentioned bow shape, but various shapes such as a trapezoid and a triangle can be adopted.

Of the pair of lids 2 and 3 described above,
Ears 2a are formed on both sides of the one lid 2, respectively. The individual ears 2a are bent at right angles to the frame 1 side at both ends of the lid 2 and fixed to the frame 1 by soldering. As means for fixing the ears 2a of the lid body 2 to the frame body 1, besides the soldering described above, for example, although not shown, a small hole is formed on the frame body 1 side and the small hole is engaged with the small hole. A small protrusion that can be fitted is formed on the ear portion 2a side, and the ear portion 2a bent at a right angle in advance is covered on the outside of the frame body 1, and at the same time, the small protrusion of the ear portion 2a is locked in the small hole of the frame body 1. Various means are conceivable such as fixing both.

On the other hand, notches 3a are formed on both sides of the other lid 3, corresponding to the locations where the guides 6 are arranged near the board insertion port 5. These notches 3a are for facilitating the soldering work when fixing a printed circuit board (not shown) to the case body 4 by soldering.

Further, bifurcated stators 7 extend integrally from both ends of the U-shaped frame body 1, and the case body 4 has a mother board (not shown) via these stators 7. It will be implemented in. That is, a slit hole into which the stator 7 of the case body 4 can be inserted is preliminarily formed in the mother board (not shown) on which the shield case is mounted, and the stator 7 is inserted into the slit hole. The entire case is supported by the mother board.

In addition, a window 8 is formed in the frame body 1 of the case body 4.
Has been drilled. The window portion 8 is for confirming whether or not a printed circuit board (not shown) is inserted in a prescribed position, and is separated from the frame body by a distance substantially the same as the distance from the lid body 3 to the guide portion 6. 1 is drilled. The shape of the window 8 is not limited to the round hole as shown in the figure, and may be, for example, a square hole or a triangular hole. Further, the formation location is not limited to one location and may be formed in a plurality of locations. Good.

Next, the procedure for attaching the printed circuit board to the shield case having the above structure will be described. First, as shown in FIG. 3, the printed board 10 on which various electronic components are mounted is inserted into the case from the board insertion opening 5 of the case body 4 as indicated by an arrow in the figure. At this time, as shown by the alternate long and short dash line in the figure, the printed circuit board 1 is provided between the guide pieces 6a and 6b of the guide portion 6 formed on the frame body 1.
The printed circuit board 10 is inserted so that both end portions of 0 are fitted.

By the way, the printed circuit board 1 is attached to the case body 4.
In order to suppress the rattling of the printed circuit board 10 as much as possible and to position the printed circuit board 10 with high accuracy with 0 inserted, the gap between the guide pieces 6a and 6b of the guide portion 6 is set to be substantially the same as the thickness dimension of the printed circuit board 10. Must be set to. However, on the other hand, in order to facilitate the insertion of the printed circuit board 10 into the case body 4, contrary to the above, the guide piece 6a, the gap having a sufficient margin with respect to the thickness dimension of the printed circuit board 10, It is necessary to set between 6b.

Therefore, in this embodiment, in order to eliminate the above-mentioned inconvenience, the guide portion 6 formed near the board insertion port 5 is formed.
3, the one guide piece 6b corresponding to the component mounting surface of the printed circuit board 10 is attached to the lid body 2, as shown in FIG.
Printed circuit board 1
A large opening degree θ of the guide portion 6 with respect to 0 is secured. Therefore, insertion of the printed circuit board 10 is facilitated as much as the degree of opening θ of the guide portion 6 is secured.
At the same time, by setting the minimum gap G between the guide pieces 6a and 6b to be substantially the same as the thickness dimension of the printed circuit board 10, it is possible to suppress rattling of the printed circuit board 10 in the inserted state as much as possible.

Next, as shown in FIG. 4, each guide portion 6
While the both ends of the printed circuit board 10 are still fitted between the guide pieces 6a and 6b, the tip of the printed circuit board 10 is abutted against the frame 1 of the case body 4. At this point, the case body 4
On the other hand, whether or not the printed circuit board 10 is inserted in the proper position is confirmed through the window 8.

Here, in the case structure of this embodiment,
When both end portions of the printed circuit board 10 are properly fitted and inserted into all the guide portions 6, in other words, when the printed circuit board 10 is inserted in the regular position, the window portion for position confirmation as shown in FIG. 8 is closed at the tip of the printed circuit board 10. On the other hand, as shown in FIG. 6, when both ends of the printed circuit board 10 are inserted in a state where they are separated from any of the guide parts 6, in other words, the printed circuit board 10 is inserted.
If is not inserted in the proper position, the window 8 is not blocked by the printed circuit board 10 but is open.

Therefore, when confirming the insertion position of the printed circuit board 10 through the window 8, if the window 8 is closed at the tip of the printed circuit board 10, the printed circuit board 1
It can be determined that 0 is inserted in the proper position, and if the window 8 is not closed, the printed circuit board 10
It can be determined that is not inserted in the regular position. As a result, it is of course possible to easily confirm that the printed circuit board 10 has been inserted in the proper position, and even when the printed circuit board 10 is detached from the guide portion 6 at the back side of the case, which is difficult to confirm, the printed circuit board 10 can be easily inserted. Positional defects can be reliably detected and the position can be corrected before the substrate is joined.

Subsequently, the land portion 11 provided on the back surface of the printed circuit board 10 (the surface opposite to the component mounting surface) and the guide portion 6 (guide piece 6a) of the case body 4 are joined by soldering. In the shield case of this embodiment,
Notches 3a are formed at both ends of the lid body 3 corresponding to the positions where the guide portions 6 are arranged near the board insertion port 5. Therefore, when the case body 4 and the printed circuit board 10 are soldered, the soldering iron can be pressed against the joint portion through the cutout portion 3a, so that the soldering work and the subsequent soldering inspection can be easily performed. it can.

By the way, if the guide portion 6 is made too large, not only the rigidity of the frame 1 is reduced, but also
At the time of soldering, heat diffusion to the case body 4 becomes remarkable, and the solderability deteriorates. Therefore, in consideration of solderability between the case body 4 and the printed circuit board 10, it is preferable to form the guide portion 6 by projecting the guide pieces 6a and 6b as narrow as possible. Also, printed circuit board 1
Since the land portion 11 of 0 is joined to the guide portion 6 of the case body 4 by soldering, the case body 4 can be used as a grounding terminal by designing the land portion 11 as a ground on the wiring pattern. It is possible.

As described above, in this embodiment, since the case body 4 is integrally molded in a box shape by the U-shaped frame body 1 and the pair of lid bodies 2 and 3, one kind of metal is used in the manufacture thereof. A mold is sufficient, and two types of dies for a frame and a lid are not required unlike the conventional case. Further, when the printed circuit board 10 is inserted into the case body 4 integrally formed in a box shape, the insertion position of the printed circuit board 10 is regulated by the guide portion 6, and the printed circuit board 10 can be joined to the case body 4 in this state. Therefore, the relative displacement between the stator 7 of the case body 4 and the terminals 12 (see FIG. 7) of the printed circuit board 10 hardly occurs.

In the case structure of the present embodiment, the guide portions 6 are formed at four positions of the frame body 1 constituting the case body 4, but the present invention is not limited to this, and is shown in FIG. 8, for example. As described above, the guide portions 6 are formed at three locations on the frame body 1, or the guide portions 6 are formed at five or more locations (not shown). It is preferable to appropriately set the size in consideration of the sizes of the case body 4 and the printed circuit board 10.
Further, as for the joint portion of the printed circuit board 10 to the case body 4, not only is the arbitrary guide portion 6 selected as in the present embodiment and the printed circuit board 10 is joined thereto, but also all the guide portions 6 are joined. The printed circuit board 10 may be joined.

[0024]

As described above, according to the present invention,
Since the case body is integrally molded into a box shape with a U-shaped frame and a pair of lids, it is now possible to use only one type of mold, which conventionally required two types of mold. .
Therefore, the equipment cost for manufacturing the shield case can be reduced by that much, and the case cost can be reduced. Further, in the past, since the frame body and the lid body had separate structures, it was necessary to assemble them, but in the present invention, since both are integrally molded, such assembly work becomes unnecessary, and the case You can save money at a low price.

In addition, according to the present invention, when the printed board is inserted into the case body integrally formed in the box shape through the board insertion opening, the insertion position of the printed board is regulated by the guide portion. It is possible to bond the substrate to the case body while accurately positioning the substrate. This greatly improves the relative positional accuracy between the stator of the case body and the terminals of the printed circuit board.Therefore, when attaching the shield case housing the printed circuit board to the mother board, The terminals on the printed board can be smoothly inserted into the mother board.

[Brief description of drawings]

FIG. 1 is a diagram illustrating an embodiment of a shield case according to the present invention.

FIG. 2 is a development view of the shield case shown in FIG.

FIG. 3 is a diagram (No. 1) for explaining the procedure for mounting the printed circuit board.

FIG. 4 is a diagram (part 2) explaining a procedure for mounting the printed circuit board.

FIG. 5 is a view (No. 3) for explaining the procedure for mounting the printed circuit board.

FIG. 6 is a diagram illustrating a defective insertion of a printed circuit board.

FIG. 7 is a view (No. 4) for explaining the procedure for mounting the printed circuit board.

FIG. 8 is a diagram illustrating a modified example.

[Explanation of symbols]

 1 Frame 2, 3 Lid 4 Case Main Body 5 Board Insertion Port 6 Guide 8 Window 10 Printed Circuit Board

Claims (2)

[Claims] 1. A shield case for accommodating a printed circuit board on which an electronic component is mounted is integrally formed in a box shape with one end opened by a U-shaped frame and a pair of lids, and the opening is inserted into the board. A case body having a mouth is provided, and a guide portion for inserting a board is formed at a plurality of positions in the frame body of the case body so as to project inward, and the printed board can be joined to the guide portion. This is a shield case. 2. The shield according to claim 1, wherein a window portion for confirming whether or not the printed circuit board is inserted in a prescribed position is formed in the frame body of the case main body. Case.