| 摘要 |
PURPOSE:To eliminate fogs by obtaining light output necessary for image exposure from a flurescent lamp and achieve the improvement in copying efficiency by performing perliminary lighting of the fluorescent lamp and detecting and controlling the warm-up time of the fixing device. CONSTITUTION:When a main switch S is turned ON, warming-up of the heater H of a fixing device 1 is started and at the same time power is also supplied to the filament of a fluorescent lamp 5. After lapse of set time, the fluorescent lamp 5 is lighted. After starting of the lighting, a switch S closes to send the signal of warm- up completion to a control circuit 3. Next, the warm-up require time is compared with the preset time in the control circuit 3 and when it is shorter, the fluorescent lamp is put out and when it is longer, it is put out after its lihgting is further continued for a speciried time. Because of this, the tube wall temperature of the flourescent lamp becomes relatively high and therefore even if copying is not done immediate after completion of preliminary lighting, the tube wall does not cool down to 20 deg. or under, hence picture quality free from fogs may be obtained even if copying is done any time after this. |
