Dual backset latch

In a latch construction for mounting in doors and the like of the general type having a bolt longitudinally reciprocating in a door mounted housing between a forward extended position projecting from a door edge and a rearward retracted position substantially fully within the door edge, latch operating means in said housing having a longitudinally forward end operably connected to said bolt and longitudinally rearward end operably connected to an actuation means, said actuating means being rotatable about a transverse axis to displace said operating means to reciprocate said bolt, the longitudinal distance between the door edge and said transverse axis of said actuating means constituting backset, the improvement comprising:

• plural mutually intersecting cam means within said housing interposed between said actuation means and said latch operation means and operable in rotation within said housing about parallel but offset relative to said door edge transverse axes for alternatively connecting said actuating means with different backset to said operating means and for converting the rotary action of said actuating means to the reciprocating action of said operating means and thereby reciprocate said bolt;
• each of said intersecting cam means comprises a disc having opposed protruding cam surfaces;
• each of said intersecting cam means further comprising a disc having a spindle slot extending through one edge of said disc;
• a first forward cam means having opposed first protruding cam surfaces disposed towards its forward side and a first spindle slot disposed towards its rear side;
• a second rear cam means having opposed second protruding cam surfaces disposed towards its forward side and a second spindle slot intersecting said second cam surface;
• said first spindle slot on said forward cam intersects and forms an offset continuation of said second spindle slot on said second rear cam;
• said protruding cam surfaces on said forward cam means and said protruding cam surfaces on said rear cam means cooperate with a plurality of latch bosses formed on said latch operating means whereby rotation of either am means in either direction retracts said latch operating means;
• and
• said latch operating means is interspaced between said cam means and being provided with an elongated slot to permit spindles on said actuating means to pass through and operate said cam means at one of two predetermined backset positions.