JPH0710500Y2 - Shield case for photo detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a shield case for a light receiving device used in a light receiving unit of a remote control device for home electric appliances.

<Prior Art> As shown in FIG. 4, a shield case of a conventional light receiving device has an electric component (resistor 3a, IC3
b and the connector 4) are mounted and wiring is performed. The shield case body 5 that electromagnetically shields the light receiving element 1 and the circuit board 2 is provided with a positioning piece 6 and a lifting prevention piece 7 for holding and fixing the circuit board 2.

The positioning piece 6 prevents rattling of the circuit board 2 in the A direction (front-back direction), and the lifting prevention piece 7
Is for preventing the circuit board 2 from rising in the B direction (upward) after the positioning.

In the figure, reference numerals 8 and 9 denote front and rear mounting pieces for positioning the end portion of the circuit board 2, and reference numeral 10 denotes a fall prevention piece for preventing the light receiving element 1 from falling backward.

<Problems to be Solved by the Invention> In the shield case of the conventional light receiving device described above, when the circuit board 2 is inserted into the main body 5, various electric components 3a, 3b, 4 are mounted on the circuit board 2. For automatic mounting, the shape is complicated and it is inserted manually.

When the circuit board 2 is manually attached to the main body 5, the circuit board 2
Before passing over the positioning piece 6 and the anti-floating piece 7 protruding inside the main body 5, the circuit board 2 is first inserted from the positioning piece 6 side of the light receiving window 11 side with a small protruding amount with almost no load. . At this time, the circuit board 2 is held by the front mounting piece 8. Further, if the circuit board 2 is continuously pressed with a finger, the rear surface 5a of the main body 5 expands due to its elastic deformation, and the rear end of the circuit board 2 is inserted between the prevention piece 7 and the rear mounting piece 9.

After the circuit board 2 is inserted, the front and rear positioning pieces 6 are pressed in the direction A in FIG. 4 to prevent the rattling in the horizontal direction, and the floating prevention piece 7 is elastically restored. It is supported and fixed to the main body.

However, since the circuit board 2 is manually inserted into the shield case body 5 as described above, the following problems occur.

(1) Before the circuit board 2 is inserted between the positioning piece 6 and the front mounting piece 8, the light receiving element 1 prevents the light receiving element 1 from collapsing on the bottom surface of the body.
In some cases, the lead 12 of the light receiving element 1 may be bent and the circuit board 2 may not be sufficiently inserted in a normal state.

(2) The positioning piece 6 prevents rattling of the circuit board 2 in the horizontal direction, but since the shape of the positioning piece 6 is a substantially V shape with a small amount of protrusion, it is not sufficient as a structure for preventing the circuit board 2 from rising. When the connector 4 is pushed in the direction C (rearward), the circuit board 2 floats up with its rear end as a fulcrum,
The circuit board 2 may not be positioned in a normal state.

In view of the above problems, it is an object of the present invention to provide a shield case for a light receiving device that prevents the leads of the light receiving element from bending and prevents the circuit board from rising.

<Means for Solving the Problem> The problem solving means according to the present invention is, as shown in FIGS. 1 to 3, a shield case main body 22 for electromagnetically shielding a circuit board 21 on which a light receiving element 20 is mounted, and a main body 22. For the light receiving window 23 arranged on the front surface 22a, the front mounting piece 24 for the circuit board formed to project from the inner wall of the front surface 22a of the main body 22, and the circuit board formed to project from the inner wall of the rear surface 22b of the main body 22. A rear mounting piece 25, a positioning piece 26 arranged above the front mounting piece 24 for positioning the circuit board 21 in the front-rear direction, and a circuit board 21 arranged above the rear mounting piece 25. In the shield case of the light receiving device, the positioning is performed in the shield case of the light receiving device including the rising prevention piece 27 that prevents the rising of the light receiving element and the falling prevention piece 28 that protrudes inward from the bottom surface of the main body 22 and prevents the light receiving element 20 from falling backward. Piece
An inclined guide piece 29 for guiding the rear end of the circuit board 21 so that the rear end of the circuit board 21 is first interposed between the rear mounting piece 25 and the lifting prevention piece 27 when the circuit board 21 is mounted is provided near the 26. The guide piece 29 is
It is formed so as to project from the positioning piece 26 and have a larger projecting dimension or projecting angle than the floating prevention piece 27.

<Operation> In the means for solving the above problems, when the circuit board 21 having the light-receiving element 20 or the like mounted therein is inserted into the main body 22, the circuit board 21 is held horizontally and pressed downward, so that the front and rear surfaces 22a of the main body 22 are twenty two
When b is pushed out by its elastic deformation and the circuit board 21 is further pushed downward, the prevention piece 27 is smaller than the protruding amount of the guide piece 29, so that the circuit board 21 first comes to the main body 22 on the prevention piece 27 side. The rear surface of the circuit board 21 is pushed open, and the rear end of the circuit board 21 is sandwiched between the rear mounting piece 25 and the prevention piece 27 to prevent the circuit board 21 from rising (FIG. 2 (b)).

Next, when the circuit board 21 is further pushed downward, the circuit board 21 spreads the front surface 22a of the main body 22 and goes beyond the lowermost end portion of the guide piece 29, and between the guide piece 29 and the front placing piece 24. And the circuit board 21 is prevented from being lifted (FIG. 2 (c)).

In this way, the guide piece 29 protrudes from the positioning piece 26 and is formed to have a larger projecting dimension or projecting angle than the floating prevention piece 27, so that the circuit board 21 is connected to the prevention piece 27 and the rear mounting piece 25 first. It is possible to control the insertion degree of the circuit board 21 so that the circuit board 21 is inserted between them.

Therefore, when the light receiving element 20 is inserted, the circuit board 21 can be inserted in a normal state without coming into contact with the falling prevention piece 28 and bending the leads of the light receiving element 20.

In addition, since the prevention piece 27 and the guide piece 29 are located above the circuit board 21 due to elastic restoration of the main body etc. after the circuit board 21 is mounted,
The circuit board 21 is sandwiched between the prevention piece 27 and the rear mounting piece 25 at one end and between the guide piece 29 and the front mounting piece 24 at the other end to prevent the circuit board 21 from floating, and thus is in a normal state. The circuit board 21 can be positioned with.

<Embodiment> An embodiment of the present invention will be described below with reference to FIGS. 1 and 2 (a).
A description will be given based on (b) and (c).

FIG. 1 is a sectional view of a shield case of a light receiving device showing an embodiment of the present invention, and FIGS. 2 (a) to 2 (c) are sectional views showing a procedure for mounting a circuit board 21 on a shield case body. Is.

As shown in the figure, the shield case of the light receiving device of the present invention includes a shield case body 22 for electromagnetically shielding the circuit board 21 on which the light receiving element 20 is mounted, a light receiving window 23 arranged on the front surface 22a of the body 22, and a body. A front mounting piece 24 for a circuit board that is formed to project from the inner wall of the front surface 22a of 22, a rear mounting piece 25 for a circuit board that is formed to project from the inner wall of the rear surface 22b of the body 22, and the front mounting piece. A positioning piece 26 arranged above 24 for positioning the circuit board 21 in the front-back direction, and a lifting prevention piece 27 arranged above the rear mounting piece 25 for preventing the circuit board 21 from rising. A tilt-preventing piece 28 that protrudes inward from the bottom surface of the main body 22 and prevents the light-receiving element 20 from tilting backward.

Then, in the vicinity of the positioning piece 26, when the circuit board 21 is mounted, the rear end of the circuit board 21 comes first with the rear mounting piece 25 and the lifting prevention piece.
An inclined guide piece 29 is provided for guiding so as to be interposed between the inclined guide pieces 29 and 27. The guide piece 29 is formed so as to protrude from the positioning piece 26 and have a larger projecting dimension or projecting angle than the floating preventing piece 27.

As shown in FIG. 1, the shield case body 22 is formed into a box-like shape with its upper surface opened by bending a single elastically deformable metal plate.

The front mounting piece 24 is arranged above the light receiving window 23, the rear mounting piece 25 is arranged at a position corresponding to the front mounting piece 24 on the rear surface 22b of the main body 22, and these are arranged on the circuit board. 21 to body 22
It keeps it from falling inside.

The positioning piece 26 is formed in a substantially V shape for pressing the circuit board 21 in the A direction, and is arranged above the front mounting piece 24.

The lifting prevention piece 27 is arranged at a position corresponding to the positioning piece 26 on the rear surface 23b of the main body 22. The prevention piece 27
Is an inclined portion 27a for guiding the circuit board 21 to the rear mounting piece 25,
After mounting the circuit board 21, the lower end pressing portion 27b for preventing the circuit board 21 from floating is formed into a substantially L shape.

The fall prevention piece 28 is provided on the bottom surface of the main body 22 with the light receiving element 20.
It is placed in a position that prevents it from falling backwards.

The guide piece 29 is formed in a substantially L shape from an inclined portion 29a that guides the circuit board 21 to the front mounting piece 24 and a pressing portion 29b that prevents the mounting circuit board 21 of the circuit board 21 from floating. Then, the inclination angle of the inclined portion 29a of the guide piece 29 is determined by the rising prevention piece 27
Is set to be larger than the inclination angle of the inclined portion 27a of the pressing portion 29b.
The distance from the front surface 22a of the body 22 of the
It is set to be longer than the distance between the pressing portion 27b and the rear surface 22b of the main body 22. Here, the tilt angle refers to the protrusion angle,
The separation distance refers to the protruding dimension.

The circuit board 21 includes a resistor 40, an IC 41 and a connector.
Electrical components such as 42 are mounted together with the light receiving element 20.

In the above configuration, the circuit board 21 is connected to the shield case body 22.
The procedure for inserting into the above will be described with reference to FIGS. 2 (a) to 2 (c).

A circuit board on which the light-receiving element 20 and the like are mounted as shown in FIG.
When the 21 is inserted into the main body 22 without load, the circuit board 21
The inclined portion 27a of 27 and the inclined portion 29a of the guide piece 29 are held substantially horizontally at their upper portions.

Next, when it is pressed down with respect to the surface of the circuit board 21 with a finger and inserted, the front and rear surfaces 22a and 22b of the main body 22 are expanded by the elastic deformation. When the circuit board 21 is further pushed downward, the prevention piece 27 is smaller than the protruding amount of the guide piece 29, so the circuit board 21 first spreads the rear surface of the main body 22 on the prevention piece 27 side, and the circuit board 21 is Continue to spread until the bottom end of the prevention piece 27 is crossed. When the circuit board 21 has passed the lowermost end of the prevention piece 27, the rear surface of the main body 22 is restored to its original shape. At this time, the end of the circuit board 21 on the prevention piece 27 side is sandwiched between the rear mounting piece 25 and the prevention piece 27, and is held so as to prevent the circuit board 21 from floating (see FIG. 2 (b). )).

Next, when the circuit board 21 inserted between the rising prevention piece 27 and the rear mounting piece 25 is continuously pushed further downward, the circuit board 21 pushes the front surface 22a of the main body 22 and spreads the circuit board 21. Continue pushing and spreading until it goes beyond the lowermost end of the guide piece 29. Then, when the circuit board 21 exceeds the lowermost end of the guide piece 29, the front surface 22 of the main body 22 is
The a is returned to its original shape by the restoration deformation, and the circuit board 21 is sandwiched between the guide piece 29 and the front mounting piece 24 and held so that the circuit board 21 is prevented from rising (see FIG. 2 ( c)).

At this time, since the positioning piece 26 is provided in the vicinity of the guide piece 29, rattling between the main body 22 and the circuit board 21 does not occur.

As described above, in this embodiment, the guide piece 29 projects from the positioning piece 26 and is formed to have a larger projecting dimension or projecting angle than the floating prevention piece 27.
The insertion degree of the circuit board 21 can be controlled so that the circuit board 21 is inserted between the rear mounting piece 25 and the rear mounting piece 25.

Therefore, the circuit board 21 can be positioned in a normal state without coming into contact with the falling prevention piece 28 when the light receiving element 20 is inserted and bending the leads of the light receiving element 20.

In addition, since the prevention piece 27 and the guide piece 29 are located above the circuit board 21 due to elastic restoration of the main body etc. after the circuit board 21 is mounted,
The circuit board 21 is sandwiched between the prevention piece 27 and the rear mounting piece 25 at one end and between the guide piece 29 and the front mounting piece 24 at the other end to prevent the circuit board 21 from floating, and thus is in a normal state. The circuit board 21 can be positioned with.

In addition, when the circuit board 21 is attached, it is not necessary to insert the circuit board 21 while keeping it horizontal, and it is not necessary to use nerves in manual work, so that the operation is simple and the production efficiency is improved.

It should be noted that the present invention is not limited to the above embodiments, and it goes without saying that many modifications and changes can be made to the above embodiments within the scope of the present invention.

For example, the positioning piece, the lifting prevention piece, and the guide piece do not have to be substantially V-shaped or L-shaped, respectively. For example, as shown in FIG. 3, the prevention piece 27 is a flat plate having an angle with the side surface of the main body 22. May be

Further, in the above embodiment, the positioning piece 26, the prevention piece 27 and the guide piece 29 may be elastic instead of giving elasticity to the main body.

<Effect of Device> As is apparent from the above description, according to the present invention, in the shield case of the light receiving device, the rear end of the circuit board comes up first with the rear mounting piece near the positioning piece when the circuit board is mounted. An inclined guide piece that guides so as to be interposed between the prevention piece and the prevention piece is provided, and the guide piece is formed so as to protrude from the positioning piece and have a larger protruding dimension or protruding angle than the floating prevention piece. The insertion condition of the circuit board can be controlled so that it is inserted between the prevention piece and the rear mounting piece first. The circuit board can be positioned in this state.

After mounting the circuit board, the circuit board has its rear end sandwiched between the lifting prevention piece and the rear mounting piece, and its front end sandwiched between the guide piece and the front mounting piece. Can be prevented and positioning can be performed in a normal state.

Further, when the circuit board is attached, it is not necessary to insert the circuit board while keeping it horizontal, and it is not necessary to use nerves in manual work, so that the operation is simple and the production efficiency is improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a shield case of a light receiving device showing an embodiment of the present invention, and FIGS. 2 (a) to 2 (c) are sectional views showing a procedure for mounting a circuit board on a shield case body.
FIG. 3 is a sectional view of a shield case showing another embodiment of the present invention, and FIG. 4 is a sectional view of a shield case of a conventional light receiving device. 20: Light receiving element, 21: Circuit board, 22, 22a, 22b: Shield case body, 23: Light receiving window, 24, 25: Front / rear mounting piece, 26: Positioning piece, 27: Lifting prevention piece 28: Fall prevention piece , 29: Information piece.

Claims (1)

[Scope of utility model registration request] 1. A shield case main body for electromagnetically shielding a circuit board on which a light receiving element is mounted, a light receiving window arranged on the front surface of the main body, and a front part for a circuit board formed to project from an inner wall of the front surface of the main body. A mounting piece, a rear mounting piece for a circuit board formed to project from the inner wall of the rear surface of the main body, and a positioning piece arranged above the front mounting piece for positioning the circuit board in the front-rear direction. A lift preventing piece arranged above the rear mounting piece for preventing the circuit board from rising, and a fall preventing piece protruding inward from the bottom surface of the main body for preventing the light receiving element from falling backward. In the shield case of the light receiving device, an inclined guide piece is provided near the positioning piece so as to guide the rear end of the circuit board so that the rear end of the circuit board is first interposed between the rear mounting piece and the floating prevention piece when the circuit board is mounted. The guide piece is provided with a positioning piece. The shield case of the light receiving device characterized by its projecting dimension or projecting angle is larger than preventing piece only protrudes One lifting.