Patent ID: 8265512
Filing Date: 2012-09-11
Classification: G03G

Abstract:
1. A power supply unit for an image forming apparatus comprising: a first control circuit configured to control the image forming apparatus that forms an image on a medium, to be transitioned among plural operation modes including a normal mode in which the image forming apparatus operates at normal power consumption and a power saving mode in which the image forming apparatus operates at other power consumption lower than the normal power consumption; a first power system configured to receive first electric power supplied from a commercial power supply, and supply second electric power to at least the first control circuit; a second power system configured to receive the first electric power supplied from the commercial power supply, and supply third electric power to a load further on a downstream side than the second power system; an electricity storing section provided on a downstream side in a power supplying direction of the second power system and charged by the third electric power from the second power system in the normal mode; a switch configured to turn off and on the first electric power from the commercial power supply to the second power system in association with open and close of a body cover, and generate fourth electric power; a second control circuit to which the fourth electric power is supplied through the switch; a cooling fan controlled by the second control circuit and configured to receive the third electric power supplied by the second power system; and a path switching section driven by the second control circuit and configured to switch, in the power saving mode, an electric power supply path to interrupt the third electric power from the second power system to the cooling fan and supply fifth electric power from the electricity storing section to the cooling fan.