GB2275573A

GB2275573A - Attachment device for a push-button switch

Info

Publication number: GB2275573A
Application number: GB9401964A
Authority: GB
Inventors: Tsunesuke Takano
Original assignee: Daiichi Denso Buhin Co Ltd
Current assignee: Daiichi Denso Buhin Co Ltd
Priority date: 1993-02-19
Filing date: 1994-02-02
Publication date: 1994-08-31
Also published as: KR940021298U; DE4404101A1; GB9401964D0; DE4404101C2; CA2115283A1; JPH0664334U; CN1092552A

Abstract

A device for attaching a push-button switch (4) to an insulating base member (1) comprises a pair of opposed, locking pieces (2) integrally formed with so as to upstand from the base member (1) and resiliently movable relative to one another, a hole (3) being formed in the base member (1) between the locking pieces (2) to receive therein the push-button (4a) of the switch (4), the hole (3) being slightly larger than the push-button (4a). The device further comprises an insulating plate (6) in which are formed holes (6a) to receive therethrough electrical connection terminals (5) on the side of the switch (4) opposite the push-button (4a), the insulating plate (6) including projections (6b) on opposed edges thereof which locate by a snap fit into locking formations (2a) formed in the locking pieces (2) in opposition to the resiliency of the locking pieces (2), whereby the switch (4) is securely retained between the base member (1) and the insulating plate (6). <IMAGE>

Description

ATTACHMENT DEVICE FOR A PUSH-BUTTON SWITCH The present invention relates to an attachment device for push-button switches such as switches used to turn interior lamps on and off in automobiles and so forth.

An example of an attachment device for this type of operating part is described in U.M. Laid-open gazette 4-25125 which was previously proposed by the present applicant.

In this prior art, in addition to providing a hole in an attaching body formed from plastic, a pair of locking ledges are provided protruding from the surface of said attaching body on both sides of this hole in a device that attaches an operating part such as a push-button switch and so forth to an attaching body. In addition, a pair of locking edges, hood and locking wall are formed on the surface of an attaching body near the edge of said hole. Together with the edge of a flange of the operating part inserted between the lower surface of said hood between these locking ledges and the surface of the attaching body being locked by said pair of locking ledges and said locking wall, the operating knob of the operating part is exposed on the opposite surface of the attaching body via said hole.

Although the above-mentioned prior art allows a pushbutton switch to be attached to the locking ledges and hood of a base with its flange without using a means of fastening, it has the shortcoming of being unable to be applied to pushbutton switches of the box type which do not have a flange.

It would be desirable, in order to eliminate the abovementioned disadvantages of the prior art, to be able to attach a push-button switch not having a flange to a plastic base in a single operation without using a means of fastening, and to prevent indiscriminate operation.

According to the present invention there is provided a device for attaching a push-button switch to an insulating base member comprising a pair of opposed locking pieces integrally formed with, to upstand from, the base member and resiliently movable relative to one another, and, between said locking pieces, a hole through the base member slightly larger than the push-button of the switch and through which the pushbutton extends with the switch located on the base member between the locking pieces, the device further comprising an insulating plate through which are formed holes each adapted to receive therethrough an associated electrical connection terminal formed on the side of the switch opposite to the push-button thereof, the insulating plate including projections on opposed edges thereof for snap fit co-operation with corresponding receiving means provided in the locking pieces in opposition to the resiliency between said locking pieces.

Preferably the locking pieces are each provided with a bevelled surface thereon inclined towards the receiving means to guide the associated projection on the insulating plate into snap-fit co-operation with said receiving means.

Conveniently the insulating plate comprises a printed circuit board, the electrical connection terminals on the switch extending through holes formed in the conducting portions of the board and being secured, for example by soldering, to said conducting portions.

As the top and the bottom of the switch, considered in the direction of pushing of the push-button, are supported by being gripped between the inner surface of the base member and the inner surface of the insulating plate, the switch itself cannot move indiscriminately in the direction of pushing.

Furthermore, other undesired movement of the switch in other directions is restricted by appropriate insertion of the push-button into the hole in the base member, and by insertion of the connection terminals into associated holes in the insulating plate which is itself fixed in position by resilient co-operation with the locking pieces.

By way of example only, an embodiment of the invention will now be described in greater detail with reference to the accompanying drawings of which: Fig. 1 is an exploded perspective view showing a first embodiment of the present invention.

Fig. 2 is a longitudinal sectional view showing a second embodiment of the present invention.

Fig. 3 is a perspective view showing a third embodiment of the present invention.

Firstly, as shown in Figs. 1 and 2, the basic composition of the present invention consists of inserting operating piece 4a of push-button switch 4 into hole 3 of plastic base 1 between a pair of resilient locking pieces 2 integrally provided on the rear surface of said base 1 along internal pieces la.

As shown in Fig. 1, in the present embodiment, since resilient locking piece 2 forms a box composed of four walls 2 and 2', the resilient efficiency of resilient locking piece 2 is extremely large in comparison with that composed of a pair of resilient locking pieces 2.

Next, connection terminals 5 provided protruding from the opposite surface of operating piece 4a of this push-button switch 4 are inserted through holes 6a of insulating plate 6, spreading open projections 6b provided on both sides of this insulating plate 6 in opposition to the resiliency of said resilient locking pieces 2. Said projections 6b are locked by making resilient contact with locking ledges 2a to hold push-button switch 4 between this insulating plate and base 1, thus composing the attachment device for a push-button switch according to the present invention.

Furthermore, one of the pair of resilient locking pieces 2 may be a fixed piece absent of resiliency having locking edge 2a. In addition, as shown in Fig. 2, guiding bevelled surfaces 2b of dimensional difference d may be provided inclined towards the inside in locking ledges 2a of said resilient locking pieces 2, thus facilitating insertion of projections 6b of said insulating plate 6 between locking ledges 2a.

Tn addition, the bottom of push-button switch 4 may be supported with base projections la.

Moreover, as shown in Fig. 3, by using a printed circuit board for insulating plate 6, inserting connection terminals 5 of push-button switch 4 through holes 6a provided in the conducting land portions 6c of said insulating plate 6, and connecting and securing these connection terminals at soldered portions 6d to said conducting land portions 6c, push-button switch 4 and printed circuit board 6 can be simultaneously attached to base 1.

At the time of use, if the operating piece 4a of pushbutton switch 4 is operated in the same manner as ordinary push-button switches, the electrical continuity between connection terminals 5 can be controlled, thereby allowing the push-button switch to be used as a self-returning or double push type switch.

The operation of push-button switch 4 can be facilitated by providing cover 4b on operating piece 4a.

In addition, the guiding bevelled surfaces provided in the locking ledges serve to promote smooth fitting of the projections of the insulating plate.

The present invention offers the advantages described below as a result of having the composition as explained above.

Since both sides in the direction of pushing operation of push-button switch 4 attached to base 1 ar supported by being pinched between the surface of base 1 and the inner surface of insulating plate 6, push-button switch 4 itself cannot move indiscriminately in its direction of pushing operation, thus offering a first advantage of the present invention of offering reliable and easy operation.

In addition, since other unnecessary movement of pushbutton switch 4 can be restricted by appropriately inserting its operating piece 4a into hole 3 of base 1 and by inserting connection terminals 5 provided protruding from the opposite side into holes 6a of insulating plate 6 fixed in position with resilient locking pieces 2 with respect to base 1, pushbutton switch 4 does not move indiscriminately in any direction, thus offering a second advantage of the present invention of, in addition to protecting the operating piece from external force, being able to maintain the prescribed position of the push-button switch for an extended period of time as a result being strongly resistant to external disturbance even when used by installing in moving bodies such as passenger cars and so forth.

Claims

1. A device for attaching a push-button switch to an insulating base member comprising a pair of opposed locking pieces integrally formed with, to upstand from, the base member and resiliently movable relative to one another, and, between said locking pieces, a hole through the base member slightly larger than the push-button of the switch and through which the push-button extends with the switch located on the base member between the locking pieces, the device further comprising an insulating plate through which are formed holes each adapted to receive therethrough an associated electrical connection terminal formed on the side of the switch opposite to the push-button thereof, the insulating plate including projections on opposed edges thereof for snap fit co-operation with corresponding receiving means provided in the locking pieces in opposition to the resiliency between said locking pieces.

2. A device as claimed in claim 1 in which the locking pieces are each provided with a bevelled surface thereon inclined towards the receiving means to guide the associated projection on the insulating plate into snap-fit co-operation with said receiving means.

3. A device as claimed in claim 1 or claim 2 in which the insulating plate comprises a printed circuit board, the electrical connection terminals on the switch extending through holes formed in the conducting portions of the board and being secured, for example by soldering, to said conducting portions.

4. A device as claimed in any one of claims 1 to 3 in which the locking pieces form two opposed walls of a box the other walls of which are integral with said locking pieces and with the base member.

5. A device for attaching a push-button switch to an insulating base member substantially as described with reference to and as illustrated by the accompanying drawings.