Patent ID: 8032049

Claim:
An image forming device comprising: housing: a duct, through which air in the housing is caused to flow; a detection portion arranged outside the duct to be displaced according to the presence of, or movement of a detected body; an operating portion that can be displaced in the duct; a detection element arranged in the duct to detect displacement of the operating portion; and a transmission portion that transmits displacement of the detection portion to the operating portion through an opening formed on the duct, wherein the duct includes an intake portion, through which air is sucked, an exhaust portion, through which air is discharged, a first chamber, in which the intake portion is positioned, a second chamber, in which the detection element and the operating portion are positioned, and a prevention member that prevents foreign matters from moving to the second chamber from the first chamber while permitting ventilation of the first chamber and the second chamber.