A medium conveying apparatus includes a floating sensor located on an upstream side of a first roller in the medium conveying direction to detect a floating of the medium placed on a medium tray, a skew sensor located on a downstream side of a second roller in the medium conveying direction to detect a skew of the medium conveyed by the second roller, and a processor to determine whether the floating of the medium has occurred based on an output signal from the floating sensor, determine whether the skew of the medium has occurred based on an output signal from the skew sensor, and determine that a conveyance abnormality of the medium has occurred when the processor determines that the floating of the medium has occurred and the processor determines that the skew of the medium has occurred.

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 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 medium conveying apparatus includes a medium tray, a feed roller to feed media placed on the medium tray in order from the lower side, a brake roller located to face the feed roller, a torque limiter to control a load applied to the brake roller, and a changing member to change a limit value of a torque of the torque limiter according to a height of the media placed on the medium tray.

A medium conveying apparatus includes a driving force transmitting mechanism to transmit a driving force from a first motor to a brake roller and a pair of conveyance rollers located on the downstream side of the brake roller, and a processor to rotate the first motor forward to control so that a medium separated by the brake roller is conveyed by the pair of conveyance rollers, in a separation mode. The processor rotates the first motor backward to perform a feed operation by the brake roller and rotate the pair of conveyance rollers backward until a front edge of the medium passes through a position of the brake roller, and rotates the first motor forward to control so that the medium is conveyed by the pair of conveyance rollers after the front edge of the medium passes through the position of the brake roller, in a non-separation mode.

A medium conveying apparatus includes a setting member to set a torque limiter that defines a maximum torque applied to a brake roller to a first torque limiter or a second torque limiter, a unit including the first torque limiter, the second torque limiter and the brake roller, and a transmission member to transmit a drive force to the first torque limiter. The unit is swingably supported so that a predetermined force acts on the brake roller in a direction away from the feed roller when the driving force is transmitted. A force in a direction in which the brake roller presses the feed roller when the second torque limiter defines the maximum torque applied to the brake roller is greater than the force in the direction in which the brake roller presses the feed roller when the first torque limiter defines the maximum torque applied to the brake roller.

A flexural document pick-up device includes: a feeding path comprised of a upper wall and a lower wall; a input tray arranged upstream to the feeding path; a paper feeding unit arranged partially in the feeding path; a separation roller disposed on the opposite side of the paper feeding unit; a blocking arm disposed upstream to the paper feeding unit; a securing groove arranged on the upper wall; and a guiding unit with the following portions disposed sequentially from downstream to upstream of the feeding direction: a securing section which is secured to the securing groove, a flexure section which is extended from the securing section to the feeding path, a guiding section which is connected to the flexure section and essentially parallel to the feeding path, a lifting section which is connected to the guiding section and a vertex which is arranged on the end of the lifting section.

A medium feeding apparatus capable of switching between a first feeding mode and a second feeding mode, in which in the first feeding mode, when a first detection section positioned downstream of a feeding roller in a medium feeding direction detects passage of a trailing end of a preceding medium in a feeding standby state in which driving of the feeding roller that feeds the medium is stopped, starting the driving of the feeding roller to perform feeding of a succeeding medium, and in the second feeding mode, when a second detection section positioned downstream of the first detection section in the medium feeding direction detects the passage of the trailing end of the preceding medium in the feeding standby state, starting the driving of the feeding roller to perform the feeding of the succeeding medium.

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.