A sheet conveyor includes a separation roller, a retard roller forming a nip with the separation roller, and a load application device configured to apply a load to the retard roller. The load application device includes a motor, a first drive train, a second torque limiter isolated from the first drive train, and a controller. The first drive train includes a plurality of gears for transmitting a driving force from the motor to the retard roller, a first torque limiter, and a clutch disposed between the motor and the first torque limiter. The second torque limiter is configured to communicate with the retard roller. The controller is configured to, during conveyance of a sheet, control the clutch to allow transmission of the driving force from the motor for a predetermined time period and to interrupt transmission of the driving force from the motor after expiration of the predetermined time period.

A paper separation mechanism, comprising a separation roller assembly having a separation roller, a torque limiter connected to the separation roller, and a separation gear arranged between the separation roller and the torque limiter; a transmission gear assembly having a first transmission gear which is able to mesh or separate with the separation gear, a second transmission gear meshed with the first transmission gear, and a connecting part connected the first transmission gear and the second transmission gear; and a motor connected to the transmission gear assembly for applying forward or reverse torque; wherein when the motor is applying the forward torque, the connecting part rotates forward to mesh the first transmission gear with the separation gear; and when the motor is applying the reverse torque, the connecting part rotates reverse to separate the first transmission gear with the separation gear.

A paper separation mechanism, comprising a separation roller assembly having a separation roller, a torque limiter connected to the separation roller, and a separation gear arranged between the separation roller and the torque limiter; a transmission gear assembly having a first transmission gear which is able to mesh or separate with the separation gear, a second transmission gear meshed with the first transmission gear, and a connecting part connected the first transmission gear and the second transmission gear; and a motor connected to the transmission gear assembly for applying forward or reverse torque; wherein when the motor is applying the forward torque, the connecting part rotates forward to mesh the first transmission gear with the separation gear; and when the motor is applying the reverse torque, the connecting part rotates reverse to separate the first transmission gear with the separation gear.

A sheet conveying apparatus includes a tray having a plurality of sheets, a feeder to successively convey sheets stacked on the tray, a controller, and a double-feed sensor to detect double feed when the feeder conveys a plurality of sheets in an overlapping manner. When a double-feed length, which corresponds to a length, in a conveyance direction of the sheet, of a region in which the double feed has been detected by the double-feed sensor, is larger than a predetermined distance, the controller determines that the double feed has occurred. When the double-feed length is smaller than the predetermined distance and a sheet size is smaller than a predetermined size, the controller determines that the double feed has occurred. When the double-feed length is smaller than the predetermined distance and the sheet size is larger than the predetermined size, the controller determines that the double feed has not occurred.

An image forming apparatus includes a sheet container accommodating a recording medium therein, a sheet separating feeder including a sheet feeding body and a sheet separating body, an image forming part, and a bend applier. The sheet feeding body feeds the recording medium along with a surface movement thereof while the recording medium contacting the surface thereof. The sheet separating body forms a sheet separation nip region with the sheet feeding body and sandwiches the recording medium in the sheet separation nip region. The sheet separating feeder separates and feeds the recording medium contacting the sheet feeding body. The image forming part forms an image on the recording medium. The bend applier having a leading end of an elastic material contacts and bends the recording medium before the sheet separation nip region and generates a wrinkle extending on the recording medium in a sheet conveying direction.

A mail processing system utilizes a conveyor to shingle or de-shingle mailpieces as they move through the processing system and utilizes belts to move the mailpieces. A first shingling conveyor moves a first mailpiece to overlap with a second mailpiece to create shingled mailpieces. A second shingling conveyor moves a first mailpiece away from a second mailpiece to de-shingle them to create singulated mailpieces. A camera takes images of the mailpieces in the conveyor and image analysis software is used to determine dimensional aspects of the mailpieces that are used to control the belt speeds to move mailpieces with respect to each other. A mail processing system may include a mail processing station that scans addresses, applies postage and/or weighs the mailpieces. Mail may be de-shingled prior to being weighed and then re-shingled for subsequent processing, or mail may be shingled prior to passing through a scale if weighing is not necessary.

A sheet processing apparatus is described. The sheet processing apparatus includes a housing section, a conveyance mechanism and a controller. The housing section accommodates a sheet. The conveyance mechanism conveys the sheet accommodated in the housing section to a predetermined position at the downstream side in a sheet conveyance direction. The controller controls the conveyance mechanism to remove a needle-free binding section of a sheet bundle if a conveyance jam of the sheet occurs.

A scanner includes a reading unit that reads an image of a paper, a medium feeding portion that is capable of selecting a first feeding mode in which a separation feeding for separately feeding a paper bundle in which a plurality of sheets of paper is overlapped with each other is performed and a second feeding mode in which a non-separation feeding for collectively feeding the paper bundle without separating is performed, and a pair of first transporting rollers and a pair of second transporting rollers that transport the paper fed by the medium feeding portion, in a case in which the medium feeding portion feeds the paper in the second feeding mode, a first driven roller and a second driven roller respectively constituting the pair of first transporting rollers and the pair of second transporting rollers are driven in a rotation direction where the paper is transported.

A scanner includes a reading unit that reads an image of a paper, a medium feeding portion that is capable of selecting a first feeding mode in which a separation feeding for separately feeding a paper bundle in which a plurality of sheets of paper is overlapped with each other is performed and a second feeding mode in which a non-separation feeding for collectively feeding the paper bundle without separating is performed, and a pair of first transporting rollers and a pair of second transporting rollers that transport the paper fed by the medium feeding portion, in a case in which the medium feeding portion feeds the paper in the second feeding mode, a first driven roller and a second driven roller respectively constituting the pair of first transporting rollers and the pair of second transporting rollers are driven in a rotation direction where the paper is transported.

Provided are: a sheet feed device that is capable of suppressing the occurrence of a sheet feeding fault by changing the pressing contact force of a retard roller against a feed roller; and an image formation device equipped with the same. This sheet feed unit (50) is provided with: a pickup roller (29); a feed roller (31); a retard roller (32); a holding member (40) that holds the retard roller (32); a first biasing member (42) that biases the holding member (40); and a pressing contact force changing mechanism (60) that changes the pressing contact force of the retard roller (32) against the feed roller (31). The pressing contact force changing mechanism (60) has: a rotary shaft (61) disposed parallel to the axial direction of the retard roller (32); a cam member (70) that rotates with the rotary shaft (61); and a movable member (80) that contacts the cam member (70), moves in the axial direction in conjunction with the rotation of the cam member (70), and changes the biasing force generated by the first biasing member (42).