1480678 Retractive switches NORTHERN TELECOM Ltd 11 June 1975 [14 June 1974] 25060/75 Heading H1N A switch assembly comprises a plurality of rectangular side-by-side actuating buttons 12 pivotally mounted in an aperture 30 in a housing 10 by means of a shaft 37 passing through the buttons 12 and through two ribs 34, 35 extending along opposite sides of the aperture 30, each button 12 being biased into a non-operative position and having locating means 17 to locate it relative to the housing 10. A telephone 10 is provded with three flush mounted buttons 12, each of which has strengthening ribs 24 and a pair of spaced ribs 23 which contact a plunger 51. When a button 12 is depressed against the action of a spring 55, the plunger 51 actuates contacts 54. A projection 17 on each button 12 is biased by the spring 55 into engagement with a lip 31 on the telephone cover 10. The function of each button 12 is identified by an indicator fitted into a recess 21. Each button 12 has spaced bosses 18 which contact the lower portion of the shaft 37, the upper portion of which is contacted by a button portion (60) (Fig. 5, not shown) between the bosses 18.
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