Patent ID: 6847794

Claim:
An image forming device comprising: a control unit producing power-on and power-off signals to control individual power supplied to functional units activated by supplied power, the power-on signal being an instruction to apply electric power to the functional units while the power-off signal is an instruction to interrupt power supplied to the functional units; and a power supply unit adapted to supply each functional unit with electric power upon receiving the power-on signal and interrupt power supplied to each functional unit upon receiving the power-off signal; wherein the control unit produces an operation start signal to instruct actuation of each of the functional units and sends a respective operation start signal to each unit; each of the functional units produces an operation completion signal to report completion of a task and sends the operation completion signal to the control unit; and the control unit produces the power-on signal to the power supply unit to supply each of the functional units with power before a predetermined time of actuation of the functional unit, and upon receipt of the operation completion signal from a respective of the functional units, the control unit produces the power-off signal to the power supply unit to terminate power supply to the respective functional unit.