Pushbutton switch assembly with interlock structure

Claim 1

In a pushbutton module comprising a molded body portion; a latch bar supported in slideable relation to a face on the body portion; a plurality of pushbuttons resiliently mounted on said body portion; projections on at least two of said pushbuttons and projecting from said face on said body portion; a formation on said latch bar opposite each projection on a pushbutton; at least one pushbutton projection and the related formation interengaging such that actuation of said pushbutton engages the pushbutton projection with the related formation to slide said latch bar from an initial position, the pushbutton formation moving past said formation to permit sliding of said latch bar back to said initial position, said formation engaging with the related pushbutton projection to latch said pushbutton in its actuated position; a further one of said pushbutton projections including a resilient member, said resilient member deflecting and moving past the related formation on said latch bar on actuation of the related pushbutton, release of the pushbutton engaging said resilient member with the related formation to slide said latch bar from the said initial position to release any latched pushbutton, said latch bar slideable to said initial position on release of said resilient member from the related formation on final release of the related pushbutton; and resilient means urging said latch bar to said initial position, the improvement comprising a channel formation formed in an upper surface of an integral projection at a lower part of said face; integral projections at an upper part of said face, and a groove in each integral projection, the grooves in opposition to said channel formation, said latch bar slideably supported at a bottom edge in said channel formation at a top edge in said grooves, said latch bar retained in said slideable relation to said face on said body portion by said channel formation and said grooves.