GB2130805A

GB2130805A - Spacer for spacing apart wiring boards

Info

Publication number: GB2130805A
Application number: GB08232445A
Authority: GB
Inventors: Kazuhiro Matsui
Original assignee: Kitagawa Industries Co Ltd
Current assignee: Kitagawa Industries Co Ltd
Priority date: 1982-11-12
Filing date: 1982-11-12
Publication date: 1984-06-06
Also published as: FR2536237B1; GB2130805B; FR2536237A1

Abstract

A spacer for spacing apart printed circuit boards, having an upper substrate 1 at the centre of which a coupling hole 5 is formed, a lower substrate 2 which is disposed opposite to the upper substrate 1, a plurality of support members 3 bridging between the upper and the lower substrates 1 and 2 so as to provide a space therebetween, a curved plate 6 and a head 10. The spacer 20 spaces apart two boards A and B and a further spacer 20' can be connected to the spacer 20. <IMAGE>

Description

SPECIFICATION Spacerforspacing apart wiring boards and assembled structure thereof The present invention relates to an improvement of a spacer for spacing apart wiring boards, such as print circuit boards, to provide a suitable space between the wiring boards and for fixing the wiring boards when using a plurality of wiring boards or print circuit boards in a stacked condition, and the invention also relates to an assembled structure thereof.

Heretofore, in electronic apparatuses, when mounting a wiring board or boards on a chassis or when mounting another wiring board or boards on one wiring board, support members are used which are secured between the wiring boards and a chassis or between the wiring boards by screws so that a number of assembly processes are required for the operations of mounting the wiring boards and also there is a disadvantage in that it is expensive in mounting such parts as a large number of parts are used.

As an improvement for overcoming these disadvantages, a spacer such as disclosed in the United States Patent 3,836,703 has been proposed, which is integrally formed by using synthetic resin and which can be secured on a chassis or a wiring board in one touch by using the resiliency of the synthetic resin and by snap-fitting the same.

Although there were, to be sure, some improvements in the reduction of the number of mounting steps and the cost thereof in the spacer disclosed in the patent compared with the one in which screws and support members are used, it had also a drawback that it had a small mechanical strength against a load applied to the board in the horizontal direction or a load applied due to twisting because of its rectangular form with substrates placed in opposite to each other, by two side plates tying or bridging the substrates in order to retain the space between the wiring boards mutually, thus resulting in a tendency for the support members to fall down due to only a small load applied thereto.

According to the present invention there is provided a spacer for spacing apart wiring boards comprising an upper substrate having a flange portion at the center of which a coupling hole is formed which extends through said upper substrate; a lower substrate disposed opposite to said upper substrate; a plurality of support members extending between said upper and lower substrates and a space being formed therebetween; a resilient coupling member having a plurality of link pieces and a stem plate; and a resilient plate formed between one side of said lower substrate and one end portion of said link pieces and said stem plate, all constructing elements including said upper substrate, said lower substrate, the plurality of said support members, and said resilient plate push piece being integrally formed in one piece.

According to the present invention in another aspect there is provided an assembled structure of wiring boards or print circuit boards, and a plurality of spacers according to the invention, comprising a first wiring board or print circuit board having a mounting hole the diameter of which is slightly larger than that of the flange portion of a spacer; a second wiring board or print circuit board having a similar mounting hole; a first spacer coupled between said first and second boards with the portion thereof inserted into a mounting hole of the first board, the flange portion of the first spacer being inserted into the mounting hole of the second board; and a second spacer, the head like portion of the second spacer being inserted into the coupling hole of the first spacer through the mounting hole of the second board.

An embodiment of the invention will now be described, by way of an example, with reference to the accompanying drawings, in which:~ Figure 1 is an elevational view of a spacer constituting one embodiment according to the present invention, Figure 2 is a side view of the spacer according to the present invention partially broken away to reveal a cross-section, Figure 3 is a plan view of the spacer according to the present invention, Figure 4 is a bottom view of the spacer according to the present invention, Figure 5 is an elevational view of the spacer according to the present invention and the wiring boards or print circuit boards in a mounted condition, and Figure 6 is a cross sectional view of the spacer taken along the line A-A indicated in Figure 1.

Referring to Figures 1, 2, 3 and 4, an embodiment of a spacer according to the present invention mainly comprises an upper substrate 1 and a lower substrate 2 which are disposed opposite to each other with a predetermined distance therebetween, a plurality of support members 3 in the shape of plate respectively (in this embodiment, four support members) which tie or bridge the upper substrate 1 and the lower substrate 2, a flange portion 4, a resilient plate 6 shaped in the form of an arc or bow shape in cross-section, and a resilient coupling member 10 with thin linkage members 9 which are also in the form of small arc, respectively.

The flange portion 4 formed on the upper surface of the upper substrate 1 is to be inserted into a mounting hole formed on a wiring board or print circuit board to be mounted thereto as described later. A coupling hole 5 is formed in the centre of the flange portion 4, the detail of which is shown in Figure 2. The inner space surrounded by the support members 3 is substantially larger than the diameter of the coupling hole 5 and it has a suitable space larger than that of the resilient coupling member 10 so as not to restrain the expansion of the resilient coupling member 10.

The resilient plate 6 in the form of arc is provided generally at the center portion of the bottom of the lower substrate 2. Also, a plurality of circular notches 7 are formed on opposite sides of the link portions of the resilient plate 6 and the lower substrate 2. The root portion of the plate 6 is formed thin so as to be easily flexible.

The outer shape of the resilient coupling member 10 has generally a V-shaped head or an arrowhead like shape made of synthetic resin with a good resiliency so as to easily enable the head to be inserted into the mounting hole of the wiring board or print circuit board. A stem 8 is formed in the centre of the resilient coupling member 10, which is formed rather thick and is integrally formed with the resilient coupling member 10 made of the synthetic resin. The right and left end portions of the resilient coupling member 10 are each provided with a thin link member 9 in a curved arc shape. All the constructing elements described above are integrally formed in one piece from a synthetic resin.

Figure 5 shows the spacer according to the present invention mounted between two wiring boards or print circuit boards A and B. The mounting of the spacer on the print circuit boards can be performed as follows; First of all, the resilient coupling member 10 of the spacer 20 in accordance with the present invention is inserted by the application of pressure into a mounting hole 11 in the circuit board A. However, in this case as the diameter of the mounting hole 1 1 is slightly smaller than the maximum diameter R of the resilient coupling member 10 as shown in Figure 4, the right and left end portions of the resilient coupling member 10 in the position indicated in Figure 5 are flexed toward the inner side thereof respectively, due to the insertion by pressure while the both end portions of the resilient plate 6 are flexed toward the upper side thereof, respectively.As a result, the print circuit board A is resiliently fixed between the right and left upper end portions or edges of the resilient plate push piece 6. In this case, since the right and left end portions of the resilient coupling member return to the external side thereof by the resilient force of the thin link piece 9 shown in Figure 1, the resilient fixation of the print circuit board A can be carried out extremely securely.

Next, after inserting or fitting the flange portion 4 (see Figures 1 and 2) of the spacer into a mounting hole 11' of the other print circuit board B, a second spacer 20' having the portions 2', 3', 6' etc. may be inserted by the application of pressure into the coupling hole 5 of the first fitted spacer 20. At this time, the resilient coupling member 10' of the second spacer 20' is resiliently fixed with the coupling hole 5 of the first fitted spacer 20 while the resilient plate push piece 6' pushes down on the upper surface of the print circuit board B, thus fixing or securing the print circuit board B. In this manner, a plurality of wiring boards or print circuit boards can be successively stacked by mounting a plurality of spacers according to the present invention with each suitable space which is determined by the actual length of the spacer used.

Finally, when securing the last print circuit board, a cap member for the spacer having only the resilient plate push plate 6 and the resilient coupling member 10 is used for fixing or securing the final stage print circuit board.

As described in the foregoing, the spacer for securing the wiring boards or the print circuit boards is constructed in such a manner that the spacer mainly comprises an upper substrate at the center of which a coupling hole is formed, an lower substrate which is provided opposite to the upper substrate, a plurality of support members bridging between the upper and the lower substrates so as to retain a space therebetween, with the result that the mechanical strength against the load applied to the wiring boards or print circuit boards thus mounted in the horizontal direction and/or the load applied in the direction of twisting is extremely large, thus enabling the spacer according to the present invention not to be easily collapsed even if these large loads are applied thereto, unlike the conventional these kinds of spacers.

Moreover, when the right and left edge portions of the resilient coupling member in the form of a missile like head as shown in the drawings and described in the foregoing about the embodiment according to the present invention are coupled or engaged with the mounting hole of one print circuit board through the thin coupling pieces in the form of arc, a secured snap-fitting is obtained so that the spacer according to the present invention is strong against vibrations applied to the boards as well as the repeated loads, thus making disengagement of the spacer or spacers difficult.

In the foregoing embodiment according to the present invention, although the resilient coupling member is shown in the form of a V-shaped head, it may be any other similar shapes or it may be the one without the link piece.

Furthermore, in the spacer according to the present invention, even if the thickness of the wiring boards or print circuit boards may be changed in some degree, it can securely fix the boards by utilizing the resilient force applied in the upper and lower directions of the arc like resilient plate push piece as well as another resilient force applied in the right and left direction of the resilient coupling member.

Claims

1. A spacer for spacing apart wiring boards comprising an upper substrate having a flange portion at the center of which a coupling hole is formed which extends through said upper substrate; a lower substrate disposed opposite to said upper substrate; a plurality of support members extending between said upper and lower substrates and a space being formed therebetween; a resilient coupling member having a plurality of link pieces and a stem plate; and a resilient plate formed between one side of said lower substrate and one end portion of said link pieces and said stem plate, all constructing elements including said upper substrate, said lower substrate, the plurality of said support members, and said resilient plate push piece being integrally formed in one piece.

2. A spacer as claimed in claim 1, in which said upper substrate and said lower substrate each have a circular shape, the diameter of said upper substrate being larger than that of said lower substrate.

3. A spacer as claimed in claim 1 or claim 2, in which all of said elements are integrally formed in one piece from a synthetic resin.

4. A spacer as claimed in any preceding claim, in which said resilient coupling member has an arrow-head shape or substantially V-shaped head.

5. A spacer as claimed in any preceding claim, in which the space formed and surrounded by said support members is substantially larger than the diameter of the coupling hole.

6. A spacer as claimed in any preceding claim, in which said resilient plate has a bow-shaped or curved cross-section so as to provide a firm securing force to a wiring board when mounted due to the resiliency of the plate.

7. A spacer as claimed in any preceding claim, in which circular notches are formed on each side of a linking portion between the resilient plate and one side of the lower substrate, the root portion of the resilient plate being comparatively thin so as to allow the portions to be flexible.

8. A spacer as claimed in any preceding claim, in which the number of the support members is four.

9. A spacer as claimed in any preceding claim, in which the diameter of said coupling hole formed in the flange portion is slightly smaller than the maximum dimension of said resilient coupling member so as to enable the portion of another similar spacer to be inserted into the coupling hole of a first spacer through a mounting hole of the wiring boards to be mounted when a plurality of wiring boards are stacked.

10. A spacer for spacing apart wiring boards, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

11. An assembled structure of wiring boards or print circuit boards, and a plurality of spacers according to the invention, comprising a first wiring board or print circuit board having a mounting hole the diameter of which is slightly larger than that of the flange portion of a spacer; a second wiring board or print circuit board having a similar mounting hole; a first spacer coupled between said first and second boards with the portion thereof inserted into a mounting hole of the first board, the flange portion of the first spacer being inserted into the mounting hole of the second board; and a second spacer, the head like portion of the second spacer being inserted into the coupling hole of the first spacer through the mounting hole of the second board.

12. An assembled structure as claimed in claim 1 1, in which a plurality of wiring boards or printing circuit boards N (where N = 2, 3 4... k) and are stacked by a plurality of N-l stage spacers.

13. An assembled structure substantially as hereinbefore described with reference to and as illustrated in Figure 5 of the accompanying drawings.