Fixing Heater Duty Control for Sheet-Feed Power Reduction

The control unit calculates the transport time from the sheet feeding position to the fixing nip in advance, and starts the temperature control at a timing that ensures the fixing heater reaches the target temperature exactly when the paper sheet arrives at the fixing nip, rather than starting control at a fixed print start instruction timing

The control unit dynamically adjusts the temperature control timing and power supply amount based on the transport time parameter, which varies depending on the sheet feeding position. By changing the control parameters adaptively, the system avoids unnecessary heating while ensuring the target temperature is reached at the correct moment

Instead of using a high-power resistor that requires high current, the system uses a lower-power resistor and applies periodic power supply control. The control unit supplies power in cycles, allowing the fixing heater to accumulate heat gradually and reach the target temperature without requiring high instantaneous current

The system changes the resistance parameter by selecting a resistor with higher resistance value, and compensates for the slower heating rate by adjusting the power supply timing and duration through control algorithms, achieving the desired heating performance with lower current requirements