To provide a lock cylinder which enables key resetting without using a master key.
The lock cylinder includes a cylinder body 40 having a plug body 40, and a carrier sub-assembly 42 disposed in it. The plug body includes a plurality of spring energizing pins. A carrier assembly includes a plurality of racks engaged with pins to operate the lock cylinder. The racks and the pins move in the transverse direction to unlock the lock cylinder in response to insertion of a first effective key into the lock cylinder. A carrier 90 moves in the longitudinal direction from an operating position to a key resetting position in response to insertion of a tool into an aperture for receiving the tool. The racks are separated from the pins at the key resetting position to enable replacing a second effective key with the first effective key. In a state where the second effective key is in the lock cylinder, the first effective key becomes not used when the plug body is rotated from a receiving position.
CHONG GERALD B
| JPS545360B1 | 1979-03-15 |
Fumiaki Otsuka
Takaki Nishijima