Patent ID: 8843017
Filing Date: 2014-09-23
Classification: G03G

Abstract:
1. An image forming apparatus, comprising: a sheet feeding unit for housing a stack of sheets and supplying a sheet at a time of printing, the sheet feeding unit including a dehumidification heater; a humidity sensing element for sensing humidity; a dehumidification heater switching unit settable to maintain an ON state in which energization of the dehumidification heater is performed, or an OFF state in which the energization of the dehumidification heater is cut off; a control unit for recognizing the humidity based on an output of the humidity sensing element at a start of supply of power, for bringing the dehumidification heater switching unit into the ON state when the recognized humidity is equal to or greater than a predetermined reference value, and for bringing the dehumidification heater switching unit into the OFF state when the recognized humidity falls below the predetermined reference value; and a power supply unit for making a transition from a power saving mode, in which the supply of power to the control unit is stopped, to a normal mode, in which the supply of power to the control unit is performed when a recovery condition is met, for making a transition from the normal mode to the power saving mode when a transition condition is met, and for temporarily resuming the supply of power to the control unit in the power saving mode after the supply of power to the control unit was stopped, wherein: the control unit determines whether or not the recognized humidity is equal to or greater than a first threshold value which is larger than the predetermined reference value; and in the power saving mode, the power supply unit resumes the supply of power to the control unit in a first cycle when a latest humidity recognized by the control unit is equal to or greater than the predetermined reference value and less than the first threshold value, and resumes the supply of power to the control unit in a second cycle, which is longer than the first cycle, when the latest humidity recognized by the control unit is equal to or greater than the first threshold value.