Patent ID: 9122188
Filing Date: 2015-09-01
Classification: G03G

Abstract:
1. An image forming apparatus, comprising: a rotatable photosensitive member; a corona charging device having an opening portion opposed to the photosensitive member and configured to charge the photosensitive member; a toner image forming portion configured to form a toner image on the photosensitive member charged by the corona charging device; a sheet-shaped shield member provided on the corona charging device and configured to open and close the opening portion; a moving portion having a drive source configured to generate a driving force by a signal input to the drive source, the moving portion configured to move the shield member between a closed position at which the shield member closes the opening portion and an open position at which the shield member opens the opening portion by the driving force of the drive source; a detecting portion configured to detect a state in which the shield member is in the open position; a switch configured to activate the image forming apparatus by an operator's manipulation; and a control portion configured to control the photosensitive member to allow the photosensitive member to rotate when the detecting portion detects the state in which the shield member is in the open position and to prevent the photosensitive member from rotating when the detecting portion does not detect the state in which the shield member is in the open position, wherein the control portion operates in a mode for operating the moving portion to move the shield member in a direction for closing the opening portion in a case where the detecting portion does not detect the state in which the shield member is in the open position when the image forming apparatus is turned off by previous manipulation of the switch and where the detecting portion detects the state in which the shield member is in the open position when the image forming apparatus is activated by a manipulation of the switch subsequent to the previous manipulation, and the control portion operates the moving portion to move the shield member in a direction for opening the opening portion when the detecting portion becomes unable to detect the state in which the shield member is in the open position within a predetermined period in which the moving portion is being moved in the direction for closing the opening portion in the mode, and thereafter the control portion allows the photosensitive member to rotate when the detecting portion detects the state in which the shield member is in the open position.