JPH02123797A - Fixing structure of circuit substrate - Google Patents

Abstract

PURPOSE:To obtain interchangeability on mounting even with a small circuit substrate by screwing and fixing a fitting engaging and holding the edges of both surfaces of the engaging hole of the circuit substrate and both protrusions of the fitting to the sidewall internal surface of a housing case. CONSTITUTION:A fitting 2 interlinking and holding the edges 3a-1 of both surfaces of the engaging hole 3a of a circuit substrate 3 and both protrusions 2a-1 of the fitting 2 is screwed and fastened to the sidewall internal surface of a housing case 1. Consequently, the fitting can be sustained while forming clearances among the internal surfaces of both bent pieces 2a of the fitting 2 and the surface of the circuit substrate 3, and a wiring pattern region can be shaped up to a section near by the engaging hole 3a of the circuit substrate 3. Spaces among the mounting surface of the fitting 2 and the protrusions 2a-1 are changed, or the position of the boring of the engaging hole 3a of the circuit substrate 3 is altered as the fitting 2 is left as it is, thus also intalling a circuit substrate having different outside dimensions. Accordingly, interchangeability on mounting can be acquired.

Description

[Detailed Description of the Invention] [Summary] Regarding the fixing structure of the circuit board stored in the storage case, it is possible to design an efficient wiring pattern and provide mounting compatibility with a circuit board whose external size is relatively small. The purpose of the present invention is to provide a mounting tool for forming a screw hole in a base piece that connects a protrusion and both bent pieces on the inner surface of both bent pieces of a spring plate that bends in a U-shape, and a fitting that is inserted between the two bent pieces and engages with the protrusion. The circuit board is made up of a circuit board with a mating engagement hole bored in its edge, and the fixture is held by engaging the edges on both sides of the circuit board's engagement hole with both protrusions of the fixture. It is configured to be fixed to the case by tightening screws on the inside of the side wall.

(Industrial Application Field) The present invention relates to a structure for fixing a circuit board to be stored in a storage case.

In electronic and communication equipment, when storing and fixing circuit boards in storage cases, the fixing means does not interfere with the high-density wiring of the circuit boards, and it is easy to fix the circuit boards and replace them after fixing, and the external dimensions are small. There is a need for a fixing structure that is compatible in mounting with different circuit boards.

[Conventional technology]

Conventionally, as shown in FIG. 5(a), a side sectional view and a plan view of the main part of [bl], a circuit board 13 is attached to a mounting fixture 12 having a threaded hole 12a integrally fixed to the inner surface of a side wall 11a of a storage case 11. The mounting screws 14 are inserted into mounting holes 13a drilled at the four corners of the holder and are tightened.

[Problem to be solved by the invention]

However, according to the above-mentioned fixing structure, the fifth
As shown by the diagonal lines in Figure (b), the area occupied by the periphery of the mounting screw or the contact part of the fixture is large (this may cause problems such as the reduction of the effective area of the circuit board and the inability to design an efficient wiring pattern). There is a problem in that circuit boards of different sizes, that is, circuit boards with different mounting hole positions, cannot be replaced as is.

In view of the above-mentioned problems, it is an object of the present invention to provide a circuit board fixing structure that allows efficient wiring pattern design and is compatible with mounting even circuit boards having a relatively small external size.

[Means to solve the problem]

In order to achieve the above object, in the circuit board fixing structure of the present invention, a projection is provided on the inner surface of the double-folded piece of the spring plate bent in a U-shape, and a screw hole is provided in the base piece that connects the double-folded piece. and a circuit board having an engagement hole bored at its edge to be inserted between the two bent pieces and engaged with the protrusion, and the edges of both sides of the engagement hole of the circuit board are connected to the edges of the attachment tool. The fixture, which engages and holds both the protrusions, is configured to be screwed and fixed to the inner surface of the side wall of the storage case.

[Function] The protrusion of the fixture springs into engagement with the edge of the screen of the retaining hole of the circuit board, thereby creating a gap between the inner surface of the double-folded piece of the fixture and the surface of the circuit board. Since the wiring pattern can be held in the vicinity of the engaging hole of the circuit board, it is possible to make the wiring pattern area close to the engaging hole of the circuit board. In addition, by changing the distance between the mounting surface of the fixture and the protrusion, or by leaving the fixture as is and changing the drilling position of the engagement hole on the circuit board, mounting compatibility can be achieved with circuit boards with different external dimensions. can have.

(Example) The gist of the present invention will be explained in detail below based on the example shown in the drawings.

As shown in the exploded perspective view of the main parts in FIG. 1, the circuit board 3 is held between the fixtures 2 and fixed to the storage case 1 with mounting screws 4.

The mounting tool 2 is a bi-folded piece 2 of a metal spring plate bent into a U-shape.
A projection 2a-1 is formed by cutting the central part of the center part inward in an arcuate shape and protruding from the inner surface, and the base piece 2b that connects both bent pieces 2a is provided with a screw as shown in the rear perspective view of FIG. hole 2b
-1 is provided. The outer surface of the base piece 2b serves as a mounting surface. The interval between both bent pieces 2a is made larger than the board thickness T of the circuit board 3.

The circuit board 3 has a rectangular engagement hole 3a in its edge portion, into which the protrusion 2a-1 of the fixture 2 is fitted and secured. Square engagement hole 3
As shown in the enlarged side sectional view of the main part in Fig. 3, the dimension a is such that the edges 3a-1 on both sides of the engagement hole 3a and both protrusions 2a-1 abut and engage at the intermediate point (■) of the arcuate shape. The long side dimension A is determined as follows, and the short side dimension B is made slightly larger than the cutting width W of the protrusion 2a-1. That is, since the protrusion 2a-1 and the edges 3a-1 on both sides of the retaining hole 3a are elastically engaged, the apexes of both protrusions 2a-1 are prevented from coming into contact with each other during engagement.

To store and secure the circuit board 3 in the storage case L, first,
Place the circuit board 3 between both protrusions 2a-1 of the fixture 2.
1, both protrusions 28-1 are fitted into the engagement hole 3a, and engaged with the edges 3a-1 on both sides of the engagement hole 3a. Next, put the circuit board 3 into the storage case 1,
Align the threaded hole 2b-1 of the fixture 2 with the bow of the mounting hole 1a drilled in the side wall 1a of the storage case 1, and secure it by tightening the mounting screw 4 from the outside.

4(a) and 4(b) are a perspective view and a side sectional view showing the fixed state after assembly.

If a circuit board with small external dimensions is to be attached, it is possible to replace it with a smaller circuit board by using a fixture with a larger distance between the mounting surface of the fixture and the protrusion. Or, conversely, in advance, use large-spaced fittings,
In other words, fix the circuit board with a fixture with the protrusions and engagement holes shifted inward, and if you are replacing a circuit board with a larger external dimension, drill the engagement holes at positions that match the protrusions of the fixture. By preparing a circuit board prepared in advance, the circuit board can be replaced without changing the fixture.

In this manner, the present invention elastically engages the protrusion of the fixture with the edges on both sides of the engagement hole of the circuit board, thereby achieving
The circuit board can be held without wobbling, and a gap is ensured between the inner surfaces of the two bent pieces of the fixture and both surfaces of the circuit board, so that the wiring pattern can be formed close to the engagement hole.

Furthermore, by changing the distance between the mounting surface of the fixture and the protrusion, it is possible to provide mounting compatibility with circuit boards having different external dimensions.

In addition, since the mounting bracket is screwed from the outside of the storage case, multiple circuit boards can be arranged and fixed at intervals, and any circuit board can be easily attached or detached by removing the mounting screws. can.

Furthermore, if the side wall of the storage case is opened, the mounting tool has elasticity, so the circuit board can be inserted or removed directly in the direction of the curved surface of the protrusion, making it even easier to replace any circuit board in the event of a failure. becomes.

(Effects of the Invention) As detailed above, according to the present invention, high-density wiring can be achieved by efficiently expanding the area of the wiring pattern, and the circuit board can be easily fixed and replaced after being fixed. ,
It also allows for compatibility with circuit boards of different dimensions,
This has extremely useful effects in industry, such as being able to provide electronic and communication equipment that is inexpensive and easy to maintain.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of an embodiment of the present invention, FIG. 2 is a rear perspective view of the fixture shown in FIG. 1, FIG. 3 is an enlarged side sectional view of the main part of the engagement hole shown in FIG. 4(al) and (b) are a perspective view and a side sectional view showing the fixed state after assembly in FIG. 1, and FIG. 5(b) is a side sectional view and a plan view of the main part according to the prior art. In the figure, 1 is a storage case, 2b is a base piece, 1a is a side wall, 2b-1 is a punching hole, 2 is a fixture, 3 is a circuit board, 2a is a bent piece, 3
28-1 is a protrusion, and 3a-1 is an edge. ! ! / Fixture 2 Front perspective view fa) Perspective view and side sectional view showing the fixed state after assembly in Figure 1 and side sectional whistle 4 Figure (Part 1) Side sectional view bl tI11 sectional view Principal part 1111 sectional view and plane according to prior art 1st 5th
Diagram (Part 1)

Claims (1)

[Claims] A base piece (2) connecting the protrusion (2a-1) and the two bent pieces (2a) is attached to the inner surface of the two bent pieces (2a) of the spring plate that bends into a U-shape.
b) A mounting tool (2) having a screw hole (2b-1) on the edge; Circuit board drilled in the part (3)
edges (3a-1) on both sides of the engagement hole (3a) of the circuit board (3) and both protrusions (2) of the mounting tool (2).
A fixing structure for a circuit board, characterized in that the fixture (2) that engages and holds the circuit board (a-1) is fixed to the inner surface of the side wall (1a) of the storage case (1) by screwing.