| 摘要 |
<p>PROBLEM TO BE SOLVED: To ensure the steering operation of an automobile even when the power can not be supplied to an electronic circuit, by unlocking a key cylinder by a mechanical key engaged with a tumbler in the key cylinder. SOLUTION: A sleeve 4 is rotatably mounted in a cylinder casing 2, and a key cylinder 1 is rotatably fitted and mounted inside of the sleeve 4. In the normal operation, an existence of key searching switch 11 and a key judging switch 30 are turned on by inserting an electronic key, and an unlocking signal is transmitted to a key cylinder lock solenoid 8 to unlock the sleeve 4. On the other hand, when the power can not be supplied to a control unit, for example, when the battery dies, the tumbler 6 is set in the key cylinder 1 by inserting the mechanical key to be disengaged from the sleeve 4, which enables the key cylinder 1 to freely rotate. Thereby the steering lock can be released to cope with a state of emergency.</p> |
