JP2917758B2 - Printed circuit board housing box with vibration parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board housing box for mounting a vibration component.

[0002]

2. Description of the Related Art FIG. 5 shows an example of the prior art of a housing box for housing and holding a printed circuit board on which a buzzer is mounted (hereinafter also referred to as a printed circuit board housing box mounting a vibration component or simply a housing box).
Shown in After the printed circuit board 100 is pressed into the case 102, the cover 103 is attached to the opening of the case 102. The printed circuit board 100 is sandwiched between the inner wall surface of the case 102 and the inner surface of the cover 103. 101 is a connector.

FIG. 6 shows another prior art. After the printed circuit board 200 is pressed into the case 202, the cover 203 is attached to the opening of the case 202. Printed circuit board 200
Is pressed by the inner wall surface of the case 202. 201 is a connector.

[0004]

However, in the above-mentioned conventional printed circuit board storage box with a vibration component, the vibration between the printed circuit boards 100, 200 and the cases 102, 202 is caused by the vibration of the buzzer mounted on the printed circuit boards 100, 200. However, there is a disadvantage that unpleasant chatter vibration occurs.

The cause of the chatter is that the printed circuit board 1
There is a minute gap (clearance) between the periphery of 00, 200 and the case 102, 202, and the printed circuit board 1
The vibration of the printed circuit board 10
This is because the peripheral edges of 0 and 200 repeatedly contact the inner wall surfaces of the cases 102 and 202. Of course, the printed circuit board 10
When the clearance between the peripheral edge of 0, 200 and the case 102, 202 is almost 0, and the printed circuit boards 100, 200 are pushed into the cases 102, 202 with a strong pushing force, the printed circuit boards 100, 200 become 2
02 will be strongly pressed by the inner wall surface, and chatter will be reduced or prevented. However, in this case, the work of pushing the printed circuit boards 100 and 200 becomes extremely difficult, and the adoption thereof becomes practically impossible.

[0006] In addition, it is conceivable to connect the printed boards 100 and 200 to the screw holes provided in the cases 102 and 202 with screws, but there is a disadvantage in that the structure, the process and the material cost are increased. The present invention has been made in view of the above problems, and can prevent chatter between a printed circuit board on which a vibration component is mounted and a case for accommodating and supporting the printed circuit board while avoiding complicated structures and processes. It is an object of the present invention to provide a printed circuit board housing box equipped with a vibration component.

[0007]

According to a first aspect of the present invention, there is provided a printed circuit board storage box for mounting a vibration component , wherein a peripheral edge of the printed circuit board on which the vibration component is mounted is held on an inner wall surface and the printed board is mounted.
Of the printed circuit board housing in the thickness direction of the main surface of the circuit board.
A case having a printed circuit board accommodation hole for, before Symbol printed vibration component mounting printed circuit board accommodating box and a lid for closing the substrate accommodation hole, projecting from the inner wall surface of the case to the surface direction of the printed circuit board periphery of or the printed circuit board is pressed against the peripheral edge of the printed circuit board Te
Projecting in the direction of the surface of the printed circuit board from the case
A plurality of support protrusions having a tapered shape pressed against the inner wall surface of the printed circuit board;
A plurality of support protrusions having a tapered shape in contact with a surface;
Protruding from the lid provided detachably on the
Tapered shape that contacts the other main surface of the printed circuit board
And characterized in that:

[0008]

A printed circuit board mounted with a vibration component according to the second invention.
The box is a printed circuit board housing box according to claim 1.
At the front of the case projecting from the periphery of the lid
Equipped with a plurality of support projections with a tapered shape that contacts the inner wall surface
It is characterized by:

[0010]

According to the present invention, the periphery of the printed circuit board on which the vibrating component is mounted is pressed into contact with a plurality of support projections having a tapered shape projecting from the inner wall surface of the case. Or
A plurality of support projections having a tapered shape projecting from the periphery of the printed board on which the vibration component is mounted are pressed against the inner wall surface of the case.

According to this configuration, the following operation and effect can be obtained. First of all, compared with the conventional case where the printed circuit board is pushed in while the peripheral surface of the printed circuit board is in contact with the entire inner wall surface of the case, the printed circuit board is contacted with the peripheral edge of the printed circuit board only in contact with the tapered support protrusions. Since the pushing is performed, the printed board can be pushed into the case by the elastic deformation or the plastic deformation of the supporting projection even if there is no clearance between the supporting projection and the peripheral edge of the printed board. In this case, even if the pressing force as a whole is relatively small, the surface pressure applied to the support protrusion is large, and the above-described elastic deformation or plastic deformation of the support protrusion is realized, and the printed board can be strongly supported, Since there is no clearance, it is possible to reduce vibration of the printed board after being pushed in, and to prevent chattering noise from being generated due to the periphery of the printed board coming into contact with the inner wall surface of the case due to the vibration of the printed board.

In addition, even if the printed circuit board vibrates due to the driving of the vibrating parts, the vibration energy is only transmitted to the case through the small-sized support protrusions. The transmission efficiency is low, and it is possible to satisfactorily prevent large noise from leaking to the outside due to chatter resonance of the case. The support projections provided on the peripheral edge of the PCB
If the work for the effect is the same as above.

The tip of the support projection has a warhead shape or a semi-cylindrical shape and is substantially in point or line contact with the printed circuit board. With this configuration, even if the support protrusions that are in contact with the inner wall surface of the printed circuit board or the case are formed firmly as a whole, the contact area of the distal end portions of the support protrusions can be reduced. To a further <br/>, to case the print has a plurality of support projections in tapered contact on one main surface of the substrate, lid plurality of support projections in tapered contact the other main surface of the printed circuit board Having. With this configuration, the printed circuit board is pressed against both the main surface and the entire periphery by the support protrusions, and the excellent chatter reduction effect is exhibited for the same reasons as described above.

[0014]

The present invention will be specifically described below with reference to examples. FIG.
FIG. 2 is a plan view of the printed circuit board housing box (housing box) of this embodiment when viewed from the printed circuit board housing hole side of the case without a cover. FIG. 2 shows the housing box from the bottom side of the case. FIG. 3 is a longitudinal sectional view, and FIG. 4 is a plan view showing a state where a lid is fitted in a case.

The printed circuit board 1 is held and accommodated in a thin, shallow, rectangular box-shaped case 2 made of resin at a predetermined distance from the bottom 22 in parallel with the bottom 22. In addition,
The printed circuit board 1 includes an IC, a resistor, a capacitor,
A semiconductor component such as a diode and a buzzer (vibrating component in the present invention) 9 are mounted. And this buzzer 9
The acoustic vibration output from the case 2 is output to the outside through a sound emission hole (not shown) opened in the case 2.

The lid 3 is made of a square flat thin plate made of resin, and two fitting claws 31 are formed on two opposite sides thereof. As shown in FIG.
The cover 3 is fixed to the case 2 by being fitted into the receiving hole 23 opened in the wall portion 21 of FIG. An appropriate number of support protrusions 32 are provided on four sides forming a peripheral edge of the lid 3 in a surface direction thereof,
The support projection 32 is pressed against the inner wall surface of the case 2 to fix the lid 3. The height of the support projection 32 is about 0.5 mm, which is a size sufficient to prevent the peripheral edge of the lid 3 from contacting the inner wall surface of the case 2 due to the resonance vibration of the case 2 and the lid 3.

Next, the support structure of the printed circuit board 1 will be described. An appropriate number of support protrusions 4 project from the inner wall surface of the case 2 to each of the four sides forming the periphery of the printed circuit board 1, and the tips of the support protrusions 4 are pressed against the periphery of the printed circuit board 1. I have. Further, as shown in FIG.
The rib-shaped support protrusions 5 are bulged from the bottom 22 of the case 2 along the inner wall surface of the case 2, and the tips of the support protrusions 5 are located on the inner main surface 15 of the printed circuit board 1. It is pressed.

Further, as shown in FIG. 3, a conical support projection 6 is vertically provided from the back main surface of the lid 3 immediately above each support projection 5 with the printed circuit board 1 interposed therebetween. When the printed circuit board 1 is fixed to the case 2, both ends of the support protrusions 5 and 6 are pressed against both sides of the printed circuit board 1. Note that the clearance between both ends of the support protrusions 5 and 6 in the pinching direction is equal to or less than the thickness of the printed circuit board 1, and the lid 3 or the case 2 is elastically deformed during pinching.

The first important point here is that the tip 41 of each support projection 4 projecting in the surface direction of the printed board 1 is formed in a semi-cylindrical shape (including a semi-cylindrical shape and a triangular prism shape). For this reason, the tip surface of the support protrusion 4 comes into line contact with the peripheral edge of the printed circuit board 1 in the vertical direction. Microscopically, surface contact occurs due to deformation of the distal end surface of the support projection 4, but macroscopically, it can be regarded as line contact.

By doing so, the effect of reducing chatter described above can be obtained. The second important thing is that the tip 51 of each support projection 5 projecting in the direction perpendicular to the surface of the printed circuit board 1 is formed in a semi-cylindrical shape (including a semi-cylindrical shape and a triangular prism shape). Support projections 5
Is in line contact with the surface 15 of the printed circuit board 1 in the horizontal direction. Microscopically, surface contact occurs due to deformation of the distal end surface of the support protrusion 5, but macroscopically, it can be regarded as line contact.

By doing so, the effect of reducing chatter described above can be obtained. A third important point is that the support projection 4 is formed integrally with the support projection 5 on the support projection 5. This facilitates mold processing and mold release after molding.

A fourth important point is that the tip of the conical support projection 6 suspended from the lid 3 is pressed against the surface 16 of the printed circuit board 1. Means that the printed circuit board 1 is substantially in point contact. By doing so, the above-described chatter reduction effect can be achieved.

In the above embodiment, the tip portions 41 and 51 of the support projections 4 and 5 are formed in a semicylindrical shape.
Conical or hemispherical). Further, the support protrusion 4 may be provided on the peripheral side of the printed circuit board 2.

[Brief description of the drawings]

FIG. 1 is a plan view of a case in which a printed circuit board housing box with a vibration component according to the present embodiment is viewed from a printed circuit board housing hole side without a lid.

FIG. 2 is a partially broken plan view of the case of the storage box of FIG. 1 as viewed from the bottom side.

FIG. 3 is a longitudinal sectional view of the storage box of FIG. 1;

FIG. 4 is a plan view showing a state where a lid is fitted into a case.

FIG. 5 is a perspective assembly view of a conventional printed circuit board housing box mounted with vibration components.

FIG. 6 is a perspective assembly view of a conventional printed circuit board housing box mounted with vibration components.

[Explanation of symbols]

1 is a printed circuit board, 2 is a case, 3 is a cover, 4, 5, and 6 are support projections, and 9 is a buzzer (vibrating part).

Claims (2)

(57) [Claims] 1. A printed circuit board on which a vibration component is mounted
Hold on inner wallTogether with the main surface of the printed circuit board
Pre-printing for accommodating the printed circuit board in the thickness direction of
With a printed circuit board accommodation holeCase and,PreviousPrinted circuit board
Vibrating component mounted printed circuit board having a lid for closing the hole
In the storage box, a surface direction of the printed circuit board from the inner wall surface of the case
Projected tohandPressed against the periphery of the printed circuit boardKamata
Is the side of the printed circuit board from the periphery of the printed circuit board
And is pressed against the inner wall surface of the case.Destination
A plurality of support projections in a thin shape,Protruding from the case and on one main surface of the printed circuit board
A plurality of support protrusions with a tapered shape to abut, Projecting from the lid detachably provided on the case;
To make contact with the other main surface of the printed circuit board.
Support projections,  A printed circuit board mounted with vibration components characterized by having
Box. 2. The printed circuit board according to claim 1, wherein
In the storage box, the inner wall surface of the case is provided so as to protrude from the peripheral edge of the lid.
Features a plurality of support projections with a tapered shape that abuts
Printed circuit board housing box with vibration components.