PURPOSE: To open a door, and to improve operability by operating an internal lock handgrip with a privacy lever that moves to a vertical lock position merely by rotating the internal lock handgrip downward.

CONSTITUTION: At the actuation position of the vertical upper part of a privacy lever 14, a person outside a door inserts a tool from an access hole 44 of a handgrip for inserting into a slot 46 of an emergency cylinder 3. At that time, a privacy shaft 16 can be rotated merely counterclockwise for setting the lever 14 to a horizontal non-actuation position. Also, when the lever 14 is at a horizontal position, a lock part 36 is adjacent to the other part of a periphery lock path, and prevents the lever 14 from moving downward. In this case, when a lock assembly body is converted from left-hand application to right-hand one, the lever 14 indicates downward for the handgrip, thus preventing the rotation of an emergency cylinder button in an improper direction. Then, merely by rotating the emergency cylinder 32, the lever 14 is rotated between the positions of the horizontal and vertical actuation, thus preventing the downward rotation of the lever 14 in the right-hand application.