Method and apparatus for controlling temperature of a laser printer fuser with faster response time

摘要

An improved laser printer is provided that keeps its fuser at a standby temperature that is somewhat raised above the ambient temperature, which allows the printer to operate more quickly (to begin printing the first page) when a print job arrives at the printer. The time needed to raise the fuser's temperature is minimized, so that other printer operations become the determining factor in the time to first print parameter. The electrical energy that energizes the fuser is provided in a form that prevents light flicker, by use of AC waveform phase control, or by use of integer half cycle control. The present invention uses closed-loop feedback control, and the type of controller is a PID controller.