Foreclosure prevention device of thumb turn lock of the room door

摘要

PROBLEM TO BE SOLVED: To prevent lockout when closing a door, to enable easy locking, to facilitate assembling by effectively utilizing a space in a lock box.;SOLUTION: An operating rod 15A of a latch 11 is horizontally disposed in the central part of an internal space of a lock box 5. A latch cam 70A whose tip is engaged with the operating rod is rotatably installed at either the upper side or the lower side of the internal space on the basis of the operating rod. At the opposite side of the latch cam, a release component 31A for a thumb-turn top joint 50A and a lock piece 60A for the latch cam are installed from the front 7 side toward the back wall 8a side of the lock box. When an interior door is closed, the latch touches the edge of a door frame and moves backward to cooperatively rotate the release component according to the backward movement of the operating rod, thereby displacing the rotational position of a driving arm of the thumb-turn top joint, and rotating the lock piece for the latch cam to release one engaging part 65A of the lock piece from the engaged part 73A at the tip of the latch cam.;COPYRIGHT: (C)2010,JPO&INPIT