| 摘要 |
PURPOSE:To obtain a power controlling method which prevents an excessive current, by dividing the half cycle of power supply and supplying power to a lamp in the first half of the half cycle and supplying power to a fixing heater in the latter half. CONSTITUTION:By a phase controlling circuit using a triac, power is supplied to an exposure lamp in the first half of the half cycle from a zero crossing point to a phase angle theta1, and power is supplied to one fixing heater in the latter half from the phase angle theta1 to pi. Since the load rate is 100% and the exposure lamp and the fixing heater have the same capacity, the current becomes sine waves, and radio noise is not radiated because higher harmonic components are not included. Another fixing heater is controlled independently of the phase control of the exposure lamp to make the fixing temperature constant. |
