PUSHBUTTON KEY MODULE FOR TELEPHONES

1474298 Mechanical switches NORTHERN ELECTRIC CO Ltd 24 June 1975 [15 July 1974] 26814/75 Heading H1N In a moulded push button module 10, Fig. 1, for attaching to support member 39 of a telephone set, a plurality of push buttons 26 resiliently mounted on guides 12 have projections 45 extending through slots 19 in a face 13 of the module 10 for co-operation with a latch bar 30 slidable in opposed grooves 16 and slots 18 of projections 15, 17 on the face 13. At least one of the projections 45 has a rigid pin 46 for cooperation with a sloping face 34 of the latch bar 29 which moves against a compression spring 38 until the pin 46 is latched in recess 35, any previous operated button being simultaneously released. A further button projection 45 has a resilient arm 47 and projection 48 co-operating with a latch projection 33 with a downwardly facing inclined face 36 arranged whereby on depression of the button 26 the projection 48 yields and rides over the projection 33 but on release of the button 26 the projection 48 engages under the face 36 to slide the latch bar 30 along and release any actuated buttons. The module is attached to the telephone set by screws (not shown) inserted through holes 42 in the support 39 arid engageable in flanges 11 of the module 10. A flange 28 on the support engages projections (50) Fig. 3 (not shown) on the push buttons 26 to retain them in position. Further projections (50) on the buttons engage and operate the switch controls (51).