Abstract: A sheet feeder, which can be included in an image forming apparatus, includes a rotary body to contact and feed a recording medium to a downstream side along a sheet conveying path, a friction body disposed facing and contacting the rotary body with the sheet conveying path interposed therebetween, the friction body forming a separation nip region with the rotary body, a receiver to support the friction body at a position opposite to the separation nip region, and multiple projections to guide the recording medium toward the separation nip region. Each of the multiple projections extends toward the rotary body at respective axial ends of the rotary body and has a top face disposed upstream from the separation nip region in a sheet conveying direction between an outer circumferential surface of the rotary body and a surface of the friction body.

Abstract: A sheet feeder includes a feeding member to contact a sheet and feed the sheet downstream in a sheet conveyance direction, a friction pad disposed facing the feeding member to contact the feeding member, and a receiving table including a pad mount to hold a side of the friction pad opposite a nip between the friction pad and the feeding member. The friction pad includes a fixed range secured to the pad mount upstream from the nip and a movable range extending downstream the nip in the sheet conveyance direction. A first friction force of the pad mount to act on the movable range of the friction pad is smaller than a second friction force of the sheet to act on the movable range of the friction pad.

Abstract: A feeding device includes a paper feed tray, a detector on an image forming apparatus main body, a control member rotatably supported by the paper feed tray, and spacers. The detector includes movable pieces and contact points corresponding to the movable piece, and switches each contact point by the position of the corresponding movable piece. The control member includes a control surface formed on its outer circumferential surface with projecting and recessed portions. The projecting and recessed portions are disposed in a pattern corresponding to rotation angles in an area of the control surface facing the movable pieces. Controlling the positions of the movable pieces according to the pattern encodes paper size. Each movable piece is lined in the circumferential direction facing the control surface. The outer circumferential surface of the projecting portions is formed in a cylindrical surface shape centering around the rotational axis of the control member.

Abstract: An image forming apparatus includes an image bearer, an image forming unit, an intermediate transfer member, a secondary transfer member, an image detector, a computing device, and a conveyor device. The computing device calculates a traveling speed of the intermediate transfer member based on detection information provided by the image detector. The conveyor device continuously transports to a secondary transfer portion a plurality of recording media one by one at a predetermined interval between successive recording media. The image forming unit forms a test image at a space between successive recording-medium contact regions of the intermediate transfer member at which the recording medium contacts the intermediate transfer member. A travel distance of the intermediate transfer member from the detection position on the intermediate transfer member to the secondary transfer portion in a traveling direction thereof is shorter than the space between the successive recording-medium contact regions.

Abstract: A sheet feeding device, which is incorporated in an image forming apparatus, includes a sheet container that contains a sheet therein, an outer end part connectable to the sheet container, a sheet feeding member, a swing shaft, a sheet loading member supported by the swing shaft to swing according to an amount of sheets loaded on the loading surface, a rotary shaft, and a sheet amount indicator being rotatably supported by the rotary shaft and having a contact end contacting the sheet loading member swinging according to a remaining amount of sheets and a sheet amount display end moving in a given display range visible from the outside of the sheet feeding device. The sheet loading member has a sloped surface sloped to a loading surface of the loading member and disposed at a portion where the contact end of the sheet amount indicator contacts the loading surface.

Abstract: An image forming apparatus includes an image forming unit, first and second rotary shafts, a drive source to rotate at a predetermined low velocity and a predetermined high velocity, a first rotary transmitter connected between the drive force and the first rotary shaft, a second rotary transmitter connected between the drive force and the second rotary shaft, and a drive block member connected between the drive source and the second rotary shaft to block transmission of the drive force to the second rotary shaft when the drive source rotates at the predetermined high velocity. When the drive source rotates at the predetermined low velocity, the drive source drives the second rotary shaft using a difference in torque between an upper limit in high velocity rotation and an upper limit in low velocity rotation greater than the upper limit in high velocity rotation.

Abstract: A base plate is selectively attached to a lower surface of a main body of an image forming apparatus or to an optional sheet feeder attachable to the main body.

Abstract: A sheet inverting device includes a loop pathway including an entrance slot to which a recording medium is conveyed and an exit slot from which the recording medium is conveyed, the loop pathway forming a loop shape to convey the recording medium therethrough in a forward direction defined by a sheet conveyance direction in which the recording medium is conveyed from the entrance slot travels, and a redirectable sheet conveyance member to convey the recording medium traveling through the loop pathway in the forward direction and a reverse direction that is the reverse of the forward direction. The exit slot is configured to convey the recording medium that is conveyed by the redirectable sheet conveyance member in the reverse direction outside the sheet inverting device therethrough.

Abstract: A paper output tray, which can be included in a paper output unit in an image forming apparatus, includes a tray body, a paper support extension slidably attached to the tray body and arranged switchable between a stored state in which the paper support extension is stored in the tray body and an extended state in which the paper support extension is pulled out to extend from the tray body, and a stopper rotatably attached to the paper support extension and arranged switchable between a folded state in which the stopper is folded to the paper support extension and a standing state in which the stopper is raised from the paper support extension. With the paper support extension in the stored state and the stopper in the folded state, the stopper overlaps an outer surface of the tray body.

Abstract: A feeding device includes a paper feed tray, a detector on an image forming apparatus main body, a control member rotatably supported by the paper feed tray, and spacers. The detector includes movable pieces and contact points corresponding to the movable piece, and switches each contact point by the position of the corresponding movable piece. The control member includes a control surface formed on its outer circumferential surface with projecting and recessed portions. The projecting and recessed portions are disposed in a pattern corresponding to rotation angles in an area of the control surface facing the movable pieces. Controlling the positions of the movable pieces according to the pattern encodes paper size. Each movable piece is lined in the circumferential direction facing the control surface. The outer circumferential surface of the projecting portions is formed in a cylindrical surface shape centering around the rotational axis of the control member.

Abstract: An image forming apparatus includes an image forming unit forming an image on a sheet transported along a transport path in a printing operation; a sheet stacking unit in which the sheet ejected at the end of the transport path is stacked; a sheet detecting unit detecting the presence or absence of the sheet in the transport path; a counting unit counting number-of-sheet data of the sheet detected by the sheet detecting unit; and a control unit controlling the printing operation in accordance with a first print request from a print instructing unit for a print job and based on a count value obtained by the counting unit. The control unit clears the count value in the absence of a next print request from the print instructing unit within a predetermined time after completion of the printing operation.

Abstract: A sheet conveying device includes a holder, a friction member, a rotary conveyance member having an outer circumferential surface and forming a nip area between the outer circumferential surface thereof and the friction member, the rotary conveyance member configured to rotate while contacting the friction member, and separate and convey multiple sheet-like materials one by one at the nip area, and a pair of guides configured to lift an underside of each of the sheet-like materials at a portion facing the friction member, the pair of guides disposed upstream from the nip area in a sheet conveying direction, outside both ends in an axial direction of the rotary conveyance member, separate from the nip area from the axial direction of the rotary conveyance member, and being overlaid with the outer circumferential surface of the rotary conveyance member.

Abstract: A sheet feeder stackable in multiple levels and attachable to an image forming apparatus. The sheet feeder includes a drive source, a drive transmission unit, a first drive coupling unit, a second drive coupling unit, a sheet feed roller, and a grip roller. During operation of multiple sheet feeders stacked in the multiple levels, the drive transmission unit and the first drive coupling unit, both provided to a given sheet feeder of the multiple sheet feeders, are coupled to each other, and the first drive coupling unit of the given sheet feeder is coupled to the grip roller of an adjacent sheet feeder disposed immediately below the given sheet feeder to drive the grip roller of each of the multiple sheet feeders substantially in synchrony.

Abstract: An open/close mechanism can be used for paper trays of an image forming apparatus. The open/close mechanism includes a plate member provided on a side of a housing of the image forming apparatus and configured to pivot upon an axis between an open position and a close position, and a box member that is arranged in the housing beneath the plate member and that can be drawn out of the housing from the side. The open/close mechanism includes also includes a restricting unit that is coupled to the plate member and that abuts against the box member when the box member is set in the housing and when the plate member is in the open position thereby restricting detachment of the box member from the housing.

Abstract: A sheet feeder stackable in multiple levels and attachable to an image forming apparatus. The sheet feeder includes a drive source, a drive transmission unit, a first drive coupling unit, a second drive coupling unit, a sheet feed roller, and a grip roller. During operation of multiple sheet feeders stacked in the multiple levels, the drive transmission unit and the first drive coupling unit, both provided to a given sheet feeder of the multiple sheet feeders, are coupled to each other, and the first drive coupling unit of the given sheet feeder is coupled to the grip roller of an adjacent sheet feeder disposed immediately below the given sheet feeder to drive the grip roller of each of the multiple sheet feeders substantially in synchrony.

Abstract: A sheet transport mechanism that can be incorporated in an image forming apparatus includes a first sheet transport member, a second sheet transport member disposed downstream from the first sheet transport member in a sheet transport direction, a sheet transport path defined by and curved between the first and second sheet transport members and including a downstream section recessed from an upstream section in the sheet transport direction, and a contact member disposed at the downstream section and including a first contact portion to which the leading edge of a sheet contacts to move the contact member in a direction to recess from the sheet transport path and a second contact portion connected to the first contact portion to advance toward the sheet transport path at a position upstream from the first contact portion in the sheet transport direction to contact the surface of the sheet.

Abstract: An image forming apparatus for which a control method is performed includes a recording unit, a conveying device conveying a recording medium to the recording unit, a feeding device supplying the recording medium to the conveying device, a recording medium conveying pathway along which the recording medium travels, and a control device controlling the conveying device and the feeding device. A first partial length of the recording medium conveying pathway extending from the feeding device to the recording unit is shorter than a conveyance direction length of a maximum usable size recording medium. When the leading end of the recording medium is located between the conveying device and the recording unit after the conveying device is driven to convey the recording medium, the control device switches the feeding device from a driven state to a non-driven state to move the feeding device by the recording medium.

Abstract: A sheet feeder incorporatable in an image forming apparatus includes a sheet container to accommodate a sheet, a sheet feeding unit, a sheet conveyance member, a sheet conveying unit disposed downstream from the sheet feeding member in a sheet conveyance direction, and a controller to stop the sheet feeding unit before the sheet abuts against the sheet conveying unit and to resume the driving, and to drive the sheet conveying unit to start while rotating the sheet feeding unit. The controller adjusts a temporary stop period for the driving of the sheet feeding unit before the sheet abuts against the sheet conveying unit, according to a period in which the sheet passes first and second points determined optionally between a standby position determined prior to feeding of the sheet and a temporary stop position located before the sheet abuts against the sheet conveying unit.

Abstract: A sheet feeding device includes a sheet feed cassette, a bottom plate and an end wall mechanism. When the number of recording media sheets decreases, the bottom plate hinged at a trailing edge thereof rises about the hinged end to keep the top sheet of the recording media sheets in contact with a sheet feed roller. The end wall mechanism includes a first urging member, a first pressing member, a support member, and a second pressing member, and aligns and presses the trailing edge of the recording medium. The first pressing member urged by the first urging member and supported by the support member presses the trailing edge of the recording medium. The second pressing member urged by the second urging member moves down due to the weight of the recording medium on the second pressing member and moves up when the number of the recording media sheets decreases.

Abstract: A conveyer includes a first rotating body; a second rotating body pair; and an intermediate rotating body arranged between the first rotating body and the second rotating body pair. A curl of the recording medium is corrected by winding and bending the recording medium around and with the intermediate rotating body at a bent angle formed by a tangent line shared by the intermediate rotating body and the first rotating body, and a line on which such a tangent line of the intermediate rotating body is connected to a nip point of the second rotating body pair. The intermediate rotating body includes an escape mechanism that is capable of causing the intermediate rotating body to escape in a direction to increase the bent angle depending on the width of the recording medium.