| 摘要 |
PROBLEM TO BE SOLVED: To prevent a unit device having the same size as that of another unit device, but a different function, from being erroneously inserted into the unit chamber of another unit device. SOLUTION: A notched section 8e is formed on a unit device 7B and a projecting member 11 is provided in a unit chamber 5B. When the unit device 7B is pushed in the unit chamber 5B, the projecting member 11 enters the notched section 8e and the inserting operation of the unit device 7B is permitted. When another unit device is inserted into the unit chamber 5B, the unit device comes into contact with the projecting member 11 and the insertion of the unit device into the unit chamber 5B is inhibited. |
