| 摘要 |
PROBLEM TO BE SOLVED: To prevent the insertion of a key into a key inserting port when a knob is placed at positions excepting a LOCK position, SOLUTION: The knob 13 rotatable around the axis of a body 12 is installed into the body 12, and the key inserting port 15, into which the key is inserted, is formed at the outer end section of the knob 13. A shutter 17 is mounted slidably into the knob 13 so as to be able to take the place of opening, where the key inserting port 15 is opened, and the place of closing, where the key inserting port is closed. The shutter 17 is locked at the place of closing when the knob 13 is changed over at positions excepting the LOCK position. |
