Door latch assembly with backset adjustment

A latch assembly having a backset adjustment for mounting within a bore extending in from a side edge of a door and operable by a handle or keylock on a side of the door, the handle or keylock positioned on a rotational axis, the latch assembly comprising:

• a casing assembly for mounting in the bore of a door, the casing assembly having a bolt assembly longitudinally reciprocal therein between a retracted position and an extended position;
• the bolt assembly including a bolt with a cylindrical aperture therein, the bolt rotatable and reciprocal relative to a non-rotational cylindrical bolt adjuster and having a sliding fit thereon, a groove extending for at least 180.degree. around the surface of the bolt adjuster, the bolt having an internal projection engageable in the groove of the bolt adjuster;
• a bolt extension connected at one end to the bolt adjuster and reciprocal with the bolt assembly;
• a cam actuating means connected to the other end of the bolt extension, the cam actuating means having a pivot connection coaxial with the rotational axis of the handle or keylock;
• the casing assembly including a rear casing with a back portion containing retaining means for rotatably constraining the cam actuating means, the back portion of the rear casing integral with a front hollow cylindrical portion with a non-helical substantially serpentine shaped slot extending about a portion of the circumference thereof;
• a forward hollow cylindrical casing rotatable and slidable about the front portion of the rear casing, the forward casing having an internal protrusion engageable in the non-helical substantially serpentine shaped slot of the front portion of the rear casing;
• and
• the forward casing engaging the bolt with the forward casing and bolt simultaneously rotatable through significantly different patterns of movement at least 180.degree. to change the backset.