GB1374544A - Electric pushbutton switches - Google Patents

Abstract

1374544 Retractive switches OAK INDUSTRIES Inc 14 Dec 1972 [10 Aug 1972] 57665/72 Heading H1N A retractive push-button switch, Figs. 4 and 7, comprises an insulating base 20 having a number of sides 24 together with internal ribs 50 forming a chamber within which a movable resilient contact arm 44 associated with a terminal 36 can be brought into engagement with contact 42 of a terminal 34 by means of a protuberance 54 on the underside of an insulated push button 22 acting on the contact arm, via an upwardly directed tongue 48, against the action of spring 56, the push-button being telescopically mounted with respect to the base. The terminals extend outwardly of the base through openings 38, 40 and the arrangement of the tongue 48 gives an effective length to the contact arm greater than both its actual length and the distance between the terminals. Button 22 which masks the base and has the same general configuration, with the option of an outwardly extending skirt (Fig. 8, not shown), is retained on the base by lugs 64 (Fig. 6) which are snapped over outwardly extending hooks 62, and is guided by mating rails 60 formed within each side of the button engaging in slots 58 in each side of the base. In a modified form (Figs. 9-13, not shown) the button is effectively twice the size of that already described and the snap-on telescopic assembly and guide means are located with respect to outwardly extending wing portions of the base. The contacts can be of the break type. A plurality of switches may be mounted together to form a keyboard inchiding a printed circuit board 16 (Figs. 1 and 2, not shown) with the switch terminals extending through and being soldered thereto, the assembly being stiffened by the provision of a rebate 30 around the switch base (Fig. 6) which fits within openings in a metal or similar plate 32 and which is spaced from the printed circuit board by feet 28.