Abstract: A sheet conveyance device for conveying a recording medium includes a fixed roller, a movable roller, an urging member, and a shock absorber, and an image forming apparatus including the sheet conveyance device. The position of the fixed roller is fixed. The movable roller is disposed opposite the fixed roller to contact the fixed roller, thereby defining a nip. The urging member urges the movable member to contact the fixed roller in the absence of the recording medium in the nip and allows the movable member to separate from the fixed roller by an amount corresponding to a thickness of a recording medium when the recording medium enters the nip. The shock absorber absorbs displacement energy generated when the urging member urges the movable roller to contact the fixed roller again after the recording medium passes through the nip.

Abstract: A sheet positioning device includes a sheet setting plate, first and second regulating members disposed facing each other to move in an orthogonal direction to a sheet conveyance direction to regulate positions of two facing ends of the sheet on the plate by contacting these ends, a driving mechanism to move the first regulating member in the orthogonal direction, first and second contact detectors mounted on the first and second regulating members to detect contact of the two facing ends, and a controller to stop the driving mechanism based on detection results obtained by the first and second contact detectors. The first and second regulating members are used to adjust a position of the sheet to a predetermined position. Respective contact surfaces of the first and second contact detectors with the sheet extend over an entire maximum loadable range in a sheet setting direction on the plate.

Abstract: 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.

Abstract: 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.

Abstract: A sheet positioning device includes a sheet setting plate, first and second regulating members disposed facing each other to move in an orthogonal direction to a sheet conveyance direction to regulate positions of two facing ends of the sheet on the plate by contacting these ends, a driving mechanism to move the first regulating member in the orthogonal direction, first and second contact detectors mounted on the first and second regulating members to detect contact of the two facing ends, and a controller to stop the driving mechanism based on detection results obtained by the first and second contact detectors. The first and second regulating members are used to adjust a position of the sheet to a predetermined position. Respective contact surfaces of the first and second contact detectors with the sheet extend over an entire maximum loadable range In a sheet setting direction on the plate.

Abstract: A sheet conveyance device for conveying a recording medium includes a fixed roller, a movable roller, an urging member, and a shock absorber, and an image forming apparatus including the sheet conveyance device. The position of the fixed roller is fixed. The movable roller is disposed opposite the fixed roller to contact the fixed roller, thereby defining a nip. The urging member urges the movable member to contact the fixed roller in the absence of the recording medium in the nip and allows the movable member to separate from the fixed roller by an amount corresponding to a thickness of a recording medium when the recording medium enters the nip. The shock absorber absorbs displacement energy generated when the urging member urges the movable roller to contact the fixed roller again after the recording medium passes through the nip.

Abstract: A drive force transmitting mechanism includes a first gear rotatably supported by a first shaft element, a first gear holding unit including the first shaft element and a first support element supporting the first shaft element, a second gear rotatably supported by a second shaft element, a second gear holding unit including the second shaft element and a second support element supporting the second shaft element. The second gear holding unit moves relative to the first gear holding unit, to thereby contact and separate the second gear with and from the first gear. A drive force is transmitted from the first gear to the second gear engaged therewith. A movement of the second gear is regulated by abutting the second shaft element against a curved surface of the first support element that curves at a predetermined curvature relative to an axis line of the first shaft element.

Abstract: A drive force transmitting mechanism includes a first gear rotatably supported by a first shaft element, a first gear holding unit including the first shaft element and a first support element supporting the first shaft element, a second gear rotatably supported by a second shaft element, a second gear holding unit including the second shaft element and a second support element supporting the second shaft element. The second gear holding unit moves relative to the first gear holding unit, to thereby contact and separate the second gear with and from the first gear. A drive force is transmitted from the first gear to the second gear engaged therewith. A movement of the second gear is regulated by abutting the second shaft element against a curved surface of the first support element that curves at a predetermined curvature relative to an axis line of the first shaft element.