| 摘要 |
PURPOSE:To compensate the temperature of a photosensitive body with a simple and an inexpensive constitution and to obtain a high printing quality by changing the electrifying voltage of an electrifier in accordance with the shape change of a temperature detecting means which detects the temperature of a photosensitive member. CONSTITUTION:When the surface temperature of a photosensitive drum 1 is kept constant, a voltage proportional to the voltage of an electrifier 4 outputted from a terminal 95 is outputted, and this signal is shunted by resistances R1 and R2 and a variable resistor 4. A signal control circuit 8 outputs a signal in accordance with the shunted current, and a voltage generating circuit 9 generates the voltage of an electrifier 6 in accordance with this signal, and this voltage is kept constant. When the temperature of the photosensitive drum 1 is low, the shape of a temperature change detecting member 2 is changed, and the resistance value of the variable resistor 4 is changed, and the current value outputted from a terminal 82 is changed, and the output HV of the voltage generating circuit 8 raises the voltage of the electrifier 6. Thus, the electrifying potential is approximately constant and an excellent printing quality is obtained independently of the change of temperature. |
