To provide a cylinder lock which is small in size, low in cost, has a changeable key code, and allows the owner to release locking even if foreign matter is inserted into a keyhole to disable key operation, or a key is broken or lost.
If the authentic key for releasing the cylinder lock is broken or the like, a projection at a front tip 751a of a jig 751 is fitted into a recess formed in a front portion 200a of a front external cylinder 200, and a grip portion 751c of the jig 751 is rotated along arrows 521, 522 with a sufficiently strong force. Thus the front external cylinder 200 is broken at a location of a notch 701 formed in a peripheral surface of the front external cylinder 200, and the front portion 200a is separated from a rear portion 200b. Thereafter, by taking an internal cylinder out of the external cylinder 200, and taking a side bar out of the internal cylinder, the cylinder lock can be released without the authentic key. The lock is applicable to the cylinder lock.
GOTO KENICHI
SHIODA KOJI
| JPH07269189A | 1995-10-17 | |||
| JP2005040414A | 2005-02-17 |
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