Method and apparatus for managing the power consumption of a printer

Abstract

An improved printer is provided which includes a print engine control program that minimizes the power consumption of the paper-handling devices to allow for a smaller DC power supply. Some of the paper-handling devices are input paper trays, output paper stackers, and a duplexer, which all preferably contain a microcontroller and an individual electric motor drive. The base printer also contains a microcontroller in the print engine that controls the printer's mechanisms and various subassemblies that are used in the laser electrophotographic printing process. To maintain control of the entire paper path, the print engine sends commands to the paper-handling devices, and these devices send responses to these commands. Most of the printer's paper-handling devices receive their electrical power entirely from the base printer, which is supplied as a DC voltage. The print engine avoids the concurrent running of subsystems in cases where the functionality of the printer is not compromised. These subsystems are instead run sequentially, so their power demands do not overlap, thereby providing a reduced overall power consumption requirement that is being supplied by the printer's DC power supply. Another aspect of the present invention allows the printer to command either all or only certain individual paper-handling devices to place themselves into a 'power saver' mode.