JP2002100847A - Fixing structure of printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing structure of printed wiring board which can fix a plurality of printed wiring boards, without using fixtures such as setscrews. SOLUTION: Electronic components 3 are mounted on printed wiring boards 1, 2 disposed in a plurality of stages, and the wiring boards 1, 2 are interconnected via connectors 5, 6 thus forming a printed wiring board fixing structure. A plurality of fixtures 7 are erected on the printed wiring board at the lower stage, support pieces 7d are projectingly mounted on the tops of the fixtures 7 and plastically deformed and locked to the peripheral edge of the upper stage printed wiring board 2, thereby fixing the upper and lower printed wiring boards 1, 2. Thus a plurality of printed wiring boards 1, 2 can be fixed, without having to use fixtures such as setscrews, for reducing assembling man-hours and improve its productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for fixing a printed wiring board used in electronic equipment and the like.

[0002]

2. Description of the Related Art A large number of electronic components such as ICs, LSIs, diodes, resistors, capacitors, and LEDs are mounted on a printed wiring board used in conventional electronic devices and the like. Are connected by the circuit pattern formed in the first pattern.

In recent years, as electronic devices and the like have become smaller, printed wiring boards on which electronic components are mounted have also been required to be smaller and have higher densities.

However, since the number of electronic components that can be mounted on one printed wiring board is limited by itself, conventionally, a plurality of printed wiring boards have been combined to realize a small and high-density printed wiring board. In order to compactly store a plurality of printed wiring boards in a housing of an electronic device or the like, a printed wiring board fixing structure as shown in FIG. 7 has been conventionally employed.

That is, a plurality of spacers b are erected on the lower printed wiring board a, and the upper printed wiring board c is placed on these spacers b, and each of the printed wiring boards a,
The printed circuit boards a and c are electrically connected to each other by connectors e and f, while the space between c and the spacer b is fixed with a fixing tool d such as a screw.

[0006]

However, in the above-mentioned conventional structure for fixing a printed wiring board, a space for installing a spacer b on the printed wiring boards a and c and a mounting hole for inserting a fixing tool d are provided. The circuit patterns cannot be formed in these spaces and mounting holes, which hinders the miniaturization and high density of the printed wiring boards a and c.

[0007] Further, since a plurality of fasteners d are required to assemble the printed wiring boards a and c and the spacers b, a large number of man-hours are required for the assembling work, resulting in poor productivity. There is also.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and provides a printed wiring board fixing structure capable of fixing a plurality of printed wiring boards without using fixing tools such as screws. It is an object of the present invention to facilitate the miniaturization and high density of a printed wiring board and to improve the productivity.

[0009]

In order to achieve the above object, a printed wiring board fixing structure according to the present invention comprises a plurality of printed wiring boards on which electronic components are mounted, and a connector between each printed wiring board via a connector. A fixed structure of printed wiring boards connected to each other by connecting a plurality of fixing members to the lower printed wiring board, and plastically deforming a support piece protruding above the fixing member to form an upper printed wiring board. The upper printed wiring board is fixed to the lower printed wiring board by being locked to the peripheral portion of the printed wiring board.

According to the above-mentioned structure, the number of assembling steps can be greatly reduced as compared with the conventional fixing structure in which the spacer is fixed to the printed wiring board by the fixing tool. Since there is no need to provide a space for installing a spacer on the board or a mounting hole for inserting a fastener, the printed wiring board can be easily reduced in size and density.

In order to achieve the above object, according to the present invention, there is provided a printed wiring board fixing structure in which a support member is provided on an upper portion of a fixing member in a plurality of upper and lower stages, and a lower support member is previously printed on an upper stage. The fixing member is formed by bending the wiring member toward the wiring board.

According to the above configuration, when assembling the upper printed wiring board, the support piece protruding above the fixing member does not hinder the assembling work of the upper printed wiring board. Since the upper printed wiring board is sandwiched and supported by the upper and lower support pieces of the fixing member from above and below, even when the fixing member is installed at a position distant from the connector, the upper printed wiring board may bend vertically. Therefore, even when the size of the upper printed wiring board is large, the upper printed wiring board can be reliably fixed with a small number of fixing members.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the drawings shown in FIGS.

FIG. 1 is a perspective view showing a state in which printed wiring boards 1 and 2 provided in two stages are fixed, FIG. 2 is a side view thereof, and FIG.
FIG. 4 is an explanatory view of an operation at the time of fixing, and FIG.

The printed wiring board 1 provided at the lower stage is formed larger than the printed wiring board 2 at the upper stage, and electronic components 3 such as ICs and resistors are mounted on the printed wiring boards 1 and 2, respectively. , Between these electronic components 3
They are connected by a circuit pattern 4 formed on each of the printed wiring boards 1 and 2.

The printed wiring boards 1 and 2 are provided with, for example, two connectors 5 and 6 for electrically connecting the printed wiring boards 1 and 2 with each other.

The connectors 6 provided on the upper printed wiring board 2 are mounted on the lower surfaces at both ends of the printed wiring board 2 and are fitted from above into the connectors 5 provided on the upper surface of the lower printed wiring board 1. A gap corresponding to the height H of each of the connectors 5 and 6 is formed between the lower printed wiring board 1 and the upper printed wiring board 2. The electronic component 3 mounted on the printed wiring board 1 and the electronic component 3 and the circuit pattern 4 mounted on the upper printed wiring board 2 do not come into contact with each other.

On the other hand, a pair of fixing members 7 are provided between the printed wiring boards 1 and 2 so as to be located, for example, on a diagonal line of the upper printed wiring board 2.

As shown in FIG. 4, these fixing members 7 are formed of a metal plate such as a copper plate elongated in the vertical direction, and have a pair of legs 7a projecting from the lower ends.

Hooks 7b are provided at the ends of the legs 7a so as to protrude in the lateral direction. When the legs 7a are inserted from above into the elongated mounting holes 1a formed in the lower printed wiring board 1. Each hook 7b is locked from the lower surface to the periphery of the mounting hole 1a so that the leg 7a does not come off from the mounting hole 1a. When the fixing member 7 is attached to the plate 1, a fall prevention piece 7c for preventing the fixing member 7 from falling or tilting is formed to be bent substantially at a right angle.

On the upper end side of the fixing member 7, a pair of support pieces 7d and 7e for supporting the upper printed wiring board 2 are vertically provided so as to be separated from each other.

A gap 7f slightly larger than the thickness t of the printed wiring board 2 is formed between the support pieces 7d and 7e so that the upper printed wiring board 2 can be sandwiched from above and below. The side support piece 7e is previously
It is bent almost at a right angle in the same direction.

Next, the operation of the above-structured printed wiring board fixing structure will be described.

As in the prior art, the printed wiring boards 1 and 2 are manufactured through the printed wiring board manufacturing steps (steps S1 to S9) shown in FIG. 6 and then are assembled through the assembling steps (steps S10 to S17). Although it is incorporated in a housing (not shown) of a device or the like, the manufacturing process of the printed wiring boards 1 and 2 is the same as the conventional one, so that the description thereof will be omitted, and only the assembly process will be described.

In step S10 shown in FIG. 6, the electronic components 3 are mounted on each of the printed wiring boards 1 and 2 by the automatic component mounting machine, and the electronic components 3 which cannot be mounted by the automatic component mounting machine are manually printed in step S11. It is mounted on wiring boards 1 and 2.

When the mounting of the electronic component 3 is completed, the fixing member 7 is attached to the lower printed wiring board 1 in step S12.

The fixing member 7 is attached by inserting the leg 7a of the fixing member 7 into the mounting hole 1a formed in the lower printed wiring board 1 while elastically deforming the leg in the width direction.
After the insertion, the hook 7b protruding from the leg 7a is locked from below on the periphery of the mounting hole 1a, so that the fixing member 7 does not come off the printed wiring board 1.

After the fixing member 7 is attached to the printed wiring board 1, soldering processing of each electronic component 3 is performed in step S13. At this time, the leg 7a of the fixing member 7 also includes the frame ground (FG) of the printed wiring board 1. Soldered to, for example.

After the soldering of the fixing member 7 is completed as described above, the connector 6 mounted on the upper printed wiring board 2 is connected to the lower printed wiring board 1 in step S14.
When the two printed wiring boards 1 and 2 are electrically connected to each other from above, the periphery of the upper printed wiring board 2 passes through the unsupported upper support piece 7d. As shown in FIG. 3, the upper support piece 7e is placed on the lower support piece 7e.
As shown in FIG. 1, d is bent substantially at right angles to the printed wiring board 2 side and plastically deformed, and the upper printed wiring board 2 is sandwiched between the upper supporting piece 7d and the lower supporting piece 7e from above and below. By supporting, the upper printed wiring board 2 is fixed to the lower printed wiring board 1.

Thus, the upper printed wiring board 2 can be fixed without providing a space for providing a spacer on the upper printed wiring board 2 or a mounting hole for inserting a fixing tool.
Since the fixing is completed only by bending the upper supporting piece 7d of the fixing member 7, the number of assembling steps can be greatly reduced as compared with the case where the fixing member 7 is fixed with a conventional fixing tool.

As described above, the lower printed wiring board 1
After fixing the upper printed wiring board 2 to
After the inspection in step S16, the printed wiring boards 1 and 2 are assembled in a housing of an electronic device or the like in step S17 to complete the assembling process.

Since the upper printed wiring board 2 is supported on the lower printed wiring board 1 by the connectors 5 and 6, when the fixing member 7 is installed near the connectors 5 and 6, FIG. , The lower support piece 7e may be omitted.

Further, in the above embodiment, the case where a pair of fixing members 7 are provided on the diagonal line of the upper printed wiring board 2 has been described. It goes without saying that three or more printed wiring boards may be provided according to the weight and the like, and the present invention can be applied to a case where three or more printed wiring boards 1 and 2 are provided.

Further, when the support pieces 7d and 7e of the fixing member 7 interfere with the circuit pattern 4 formed on the printed wiring board 2, the circuit pattern 4 is formed in advance so as not to contact the support pieces 7d and 7e. Alternatively, it is necessary to interpose an insulating sheet or the like between the circuit pattern 4 and the support pieces 7d and 7e so that the circuit pattern 4 does not contact the support pieces 7d and 7e.

Further, at the upper end of the fixing member 7, FIG.
As in the modification shown in FIG. 7, a tongue-shaped support piece 7g is protruded, and this support piece 7g is inserted into a slit 2a formed in the upper printed wiring board 2. Then, the support piece 7g is twisted and plastically deformed. By deforming, the upper printed wiring board 2 may be fixed.

In this case, it is necessary to provide a slit 2a in the upper printed wiring board 2, but it requires little installation space as compared with a conventional one in which a mounting hole for inserting a fixture is opened. It is unlikely to be an obstacle to conversion.

[0037]

As described in detail above, according to the present invention, a plurality of fixing members are erected on a lower printed wiring board, and a support piece projecting above the fixing member is plastically deformed to form an upper printed wiring board. Since the upper printed wiring board is fixed to the lower printed wiring board by being locked to the peripheral edge of the board, it is assembled compared to the conventional fixing structure where the spacer is fixed to the printed wiring board by the fixing tool. The man-hours can be significantly reduced, improving productivity and
Since there is no need to provide a space for installing a spacer on the upper printed wiring board or a mounting hole for inserting a fixing member, the printed wiring board can be easily reduced in size and density.

Further, since a support piece is projected from the upper part of the fixing member over a plurality of upper and lower stages and the lower support piece is bent in advance toward the upper printed wiring board side, thereby forming the fixing member. When assembling the upper printed wiring board,
Since the support piece protruding above the fixing member does not interfere, the assembly work of the upper printed wiring board can be easily performed, and the upper printed wiring board is vertically moved by the upper and lower support pieces of the fixing member. Because it is more sandwiched and supported, even when the fixing member is installed at a position distant from the connector, it is possible to prevent the upper printed wiring board from bending in the vertical direction, and thereby the size of the upper printed wiring board Is large, it is economical because the upper printed wiring board can be securely fixed with a small number of fixing members.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a fixing structure of a printed wiring board according to an embodiment of the present invention.

FIG. 2 is a side view showing a fixing structure of the printed wiring board according to the embodiment of the present invention.

FIG. 3 is a perspective view showing a main part of a fixing structure for a printed wiring board according to an embodiment of the present invention.

FIG. 4 is a perspective view of a fixing member used for a printed wiring board fixing structure according to an embodiment of the present invention.

FIGS. 5A and 5B are perspective views showing modified examples of a fixing member used for a printed wiring board fixing structure according to an embodiment of the present invention.

FIG. 6 is a process chart showing a manufacturing process and an assembling process of the printed wiring board used for the printed wiring board fixing structure according to the embodiment of the present invention.

FIG. 7 is a perspective view showing a conventional printed wiring board fixing structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed wiring board 2 Printed wiring board 3 Electronic component 5 Connector 6 Connector 7 Fixing member 7d Supporting piece 7e Supporting piece

Claims (2)

[Claims] 1. A printed wiring board fixing structure in which a plurality of printed wiring boards on which electronic components are mounted are provided, and the printed wiring boards are connected to each other via a connector. A plurality of fixing members are erected, and a support piece protruding above the fixing member is plastically deformed and locked to a peripheral portion of the upper printed wiring board, so that the upper printed wiring board is lower than the lower printed wiring board. A fixed structure for a printed wiring board, wherein the printed wiring board is fixed. 2. The fixing member is formed by projecting a support piece over a plurality of upper and lower steps on the upper part of the fixing member, and bending the lower support piece in advance to an upper printed wiring board side. The printed wiring board fixing structure according to claim 1, wherein: