| 摘要 |
PURPOSE:To prevent deterioration in precision caused by the thermal expansion of each part of a device by constituting the device with an air purifying means, an insulation wall provided between a heat source and an optical unit, and a ventilating path exhausting the polluted air from the inside to the outside of a frame body whose one part or whole part is the insulation wall. CONSTITUTION:This device is constituted with the air purifying means 11 purifying the polluted air in the frame body and exhausting it outside the frame body, the insulation wall 13 provided between the heat source 9 and the optical unit 3, and the ventilating path 12 exhausting the polluted air from the inside to the outside of the frame body whose one part or whole part serves as the insulation wall 13. Therefore, the polluted air incorporating ozone generated on an electrifier 2 and a transfer unit 5 is led in the direction of the C to an ozone filter 10 through the ventilating path 12. However, at this time, the polluted air takes the heat from the insulation wall 13, and is finally exhausted, so that the heat from a fixing unit 9 is hardly transmitted to an exposing part 3. Thus, the deterioration in the precision of each part caused by the thermal expansion of the part can be prevented. |
