| 摘要 |
PURPOSE:To prevent an LD from deterioration and breakdown. CONSTITUTION:Safety stitches b, c are closed by shutdown of a front door. Then, a control part 32 recognizes that the front door is closed since a DOOR OPEN signal is low and makes an LDON signal low. A transistor 35 turns on by this signal to supply a drive power source to an LD 34. When the front door has been opened, all safety switches a, b, c are opened. The control part 32 recognizes that the front door has been open since the DOOR OPEN signal becomes high, and makes the LDON signal high to turn a transistor 35 off. |
