Abstract: A lock assembly includes a retaining block having a substantially rectangular recess with a shoulder defining a transition between a wider outer portion and a narrow or inner portion. A door knob shaft having a rectangular cross-section extends through the inner portion of the recess in the retaining block for extending and retracting a striker. A substantially rectangular locking bar engageable with the recess has a shape which corresponds with the recess. The locking bar has a slot at one end for engaging and capturing the door knob shaft to prevent its rotation. When the orientation of the locking bar is reversed, the locking bar rests on the shoulder of the recess and does not engage the door knob shaft.

Abstract: A lock assembly comprising an L-shaped member (30) (120) having a first plate (32) (124) and a second plate (34) (122). Secured within the L-shaped member is a solid block core (50) (140) with openings (54) (64) (74) (90) (146) for receiving portions of lock hardware.