To provide a lock device for an interior door, enabling unlocking of a thumb turn lock from the outside in a case of an emergency inside the door or misoperation disabling unlocking from the inside.
A lock device for an interior door having a thumb turn lock 1, locked/unlocked by thumb turn operation, which causes extension/retraction of a dead bolt 3 from a door side end surface, comprises: a door-inside thumb turn lever 4 on an interior surface of an interior door A for operating the thumb turn lock 1; and a door-outside thumb turn lever 2 on an outside surface of the interior door A for operating the thumb turn lock 1. The door-outside thumb turn lever 2 includes a knob 21 and an engaging part 22 for operating the thumb turn, and is configured to be detachable from the thumb turn lock 1.
Daisuke Nagano
Kentaro Fujii