Image forming apparatus and sheet positioning device using method of sheet positioning

摘要

An image forming apparatus to which a sheet positioning device can be provided to perform a sheet positioning includes an image forming device and a sheet positioning device that includes a sheet setting plate, a pair of side fence units disposed facing each other along opposite sides of the sheet setting plate to move in a lateral direction of the sheet, a moving mechanism to move the pair of side fence units, a contact member to contact and press the sheet, a position detector to detect the position of the contact member, and a controller moving the pair of side fence units when the sheet is placed on the sheet setting plate, halting movement of the pair of side fence units after the contact member has contacted and pressed the sheet, and moving the pair of side fence units again based on detection results obtained by the position detector.

主权项

1. An image forming apparatus comprising:
an image forming device to form an image on a surface of a sheet of recording media; and a sheet positioning device to position the sheet before feeding the sheet to the image forming device, the sheet positioning device including:
a sheet setting plate to accommodate the sheet of recording media set thereon;a pair of side fence units disposed facing each other along opposite sides of the sheet setting plate and configured to move in the lateral direction perpendicular to a conveyance direction of the sheet on the sheet setting plate;a moving mechanism disposed on a back side of the sheet setting plate and configured to move the pair of side fence units in the lateral direction;a contact member disposed to at least one of the pair of side fence units, protruding from a surface of the one of the pair of side fence units toward a center thereof in the lateral direction and configured to contact a lateral end of the sheet and press the sheet in the lateral direction;a position detector to detect the position of the contact member in the lateral direction on the sheet setting plate; anda controller configured to control the moving mechanism to move and stop the pair of side fence units in the lateral direction,the controller configured to:
start the moving mechanism to move the pair of side fence units in the lateral direction for approximate positioning when the sheet is placed on the sheet setting plate;stop the moving mechanism to halt movement of the pair of side fence units after the contact member has contacted and pressed the lateral end of the sheet;allow the position detector to detect the position of the pair of side fence units while the pair of side fences remains stopped; andrestart the moving mechanism to move the pair of side fence units in the lateral direction based on detection results obtained by the position detector for precise positioning of the pair of side fence units.