| 摘要 |
At least one of first and second actuator driving devices is supplied with electric power securely. When failure occurs in any one of main power line, auxiliary power line, first and second power supply lines and first and second relays, the first to third relays are controlled to be opened and closed so that failure part is separated or failure part is isolated from part where failure does not occur or supply of electric power to failure part is cut off or electric power is supplied to part to which electric power cannot be supplied.
|
