Abstract: A lock mechanism is shown having a latch bolt movable between retracted and extended positions, which latch bolt is operated by rotation of a lock cylinder at one side and a turn piece at the opposite side. A manually movable latching member operable from said opposite side of the lock mechanism is movable between a first position where operation of the latch bolt by the turn piece is prevented, and a second position where operation of the latch bolt by the turn piece is permitted. A combination lock operable from said opposite side of the lock mechanism may be used to lock the latching member in the first position thereof wherein operation of the latch bolt by the turn piece is prevented. With the combination lock set to the lock-open combination, movement of the latching member between said first and second position is permitted.

Abstract: A deadbolt lock mechanism of the single cylinder type is disclosed having a latch bolt which is movable between extended and retracted positions by a cylinder lock at one side thereof or by rotation of a thumbturn at the other side. With the latch bolt in the retracted position, the thumbturn is axially movable between operative and inoperative positions. In the operative axial position of the thumbturn, the thumbturn is operatively coupled to the latch bolt for operation thereof. In the inoperative axial position of the thumbturn, the thumbturn not only is operatively uncoupled from the latch bolt but also is prevented from rotation.

Abstract: A deadbolt lock mechanism of the single cylinder type is disclosed having a latch bolt which is movable between extended and retracted positions by means of a lock cylinder at one side thereof. A thumbturn, together with manually movable coupling control means for controlling the coupling between the thumbturn and latch bolt are located at the other side of the mechanism. In the bolt retracted position, the coupling control means is movable between coupling enabling and disabling positions to condition the coupling for operation of the latch bolt by the thumbturn in the enabling position thereof, and for disabling such latch bolt operation by the thumbturn in the disabling position. Consequently, the latch bolt is operable by the lock cylinder in any position of the thumbturn and coupling control means, whereas the thumbturn is enabled for operation of the latch bolt only when the coupling control means has been moved into enabling position.