A bi-directional paper pickup mechanism includes a pickup roller, a fastening structure, an input shaft, a first ratchet element, a second ratchet element, an actuating unit, a first transmission rotor and a second transmission rotor. The pickup roller has an inner space. The fastening structure is disposed in the inner space. The input shaft is accommodated in the inner space, and one end of the input shaft is pivotally connected to the fastening structure. The first ratchet element is mounted around the input shaft. The second ratchet element is mounted around the one end of the input shaft. The actuating unit is fastened around a middle of the input shaft to synchronously rotate with the input shaft. The first transmission rotor is mounted around the one end of the input shaft. The second transmission rotor is mounted around the other end of the input shaft.

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 printing medium feeding device includes a loading unit into which a printing medium is loaded, a pickup roller which picks up the loaded printing medium, a retard roller, a forward roller engaged with the retard roller to feed the picked-up printing medium in a first direction, a torque limiter to apply torque in a second direction opposite to the first direction to the retard roller, and a processor. The processor controls driving of the forward roller by generating a pre-driving signal to change a torque state of the torque limiter to an effective torque state for preventing multi-feeding of printing media and controls driving of the forward roller by generating a driving signal to feed the printing medium in the first direction.

A liquid ejection apparatus includes a conveying unit, a winding unit, a printing unit, and a rotation control unit. The conveying unit is configured to intermittently convey a printing medium by a predetermined feed amount. The winding unit is configured to wind the printing medium conveyed by the conveying unit. The printing unit is configured to perform printing on the conveyed printing medium. The rotation control unit is configured to control the winding unit to rotate in a winding direction at a predetermined timing after the conveying unit has started to convey the printing medium intermittently, and then cause the winding unit to rotate in a reverse direction opposite to the winding direction.

A sheet conveyance device, an image forming apparatus, and a sheet conveying method that convey a sheet in a predetermined sheet conveyance direction make a surface moving speed of a driven roller higher than a surface moving speed of a drive roller when a rotational driving force from the drive roller is transmitted to the driven roller, and by a one-way clutch that is provided at any place in a drive transmission path from the drive roller to the driven roller, restrict relative rotation of the driven roller in a first rotation direction, which is the sheet conveyance direction, with respect to the drive roller while allowing relative rotation of the driven roller in a second rotation direction, which is a direction opposite to the first rotation direction, with respect to the drive roller.

A sheet feeding apparatus includes a sheet stacker to stack at least one sheet; a sheet feed roller disposed at one side of the sheet stacker and to feed a sheet fed from the sheet stacker; a multi-feed prevention roller disposed to face the sheet feed roller and to prevent multi-feed of the sheet fed from the sheet stacker; a magnetic torque limiter disposed coaxially with the multi-feed prevention roller; a hall sensor disposed at one side of the magnetic torque limiter and to detect rotation of the magnetic torque limiter; and a controller configured to rotate the sheet feed roller in a state in which the sheet feed roller and the multi-feed prevention roller are in contact with each other without a sheet and to identify a lifetime of the multi-feed prevention roller by using a signal output from the hall sensor.

In a storage operation, a first tape and a second tape are wound around a drum with a paper sheet sandwiched therebetween to store the paper sheet, the first tape being positioned outside the paper sheet in a radial direction of the drum. In a feeding operation, the first tape is wound around a first reel, and the second tape is wound around a second reel to feed the paper sheet from the drum. In at least one of the storage operation or the feeding operation, greater tension acts on the first tape than on the second tape.

A sheet conveyor includes a drive roller, a retard roller forming a nip with the drive roller, a first torque limiter disposed coaxially with the retard roller and communicating with the retard roller, a first gear disposed coaxially with the retard roller, a drive train including a plurality of gears for receiving a driving force from the first gear, a second torque limiter, and an arm member including a contact portion located downstream of the drive roller in the conveyance direction. The arm member is movable between a first arm position to allow transmission of the driving force to the second torque limiter and a second arm position to interrupt transmission of the driving force to the second torque limiter. The arm member is configured to, as the sheet conveyed by the drive roller contacts the contact portion, move from the first arm position to the second arm position.

A document conveyance apparatus includes a feed roller, a first and a second conveyance rollers, a conveyance shaft, an arm portion rotatably moving the feed roller to a standby position to a feeding position, a transmission portion transmitting rotation of the conveyance roller shaft to the arm portion, and a torque limiter. The feed roller and the first conveyance roller rotate in a conveyance direction when the conveyance roller shaft rotates in a first direction, and the feed roller moves from a feeding position to a standby position when the conveyance roller shaft rotates in a second direction. When a document fed by the second conveyance roller moves through a nip portion, a transmission portion does not transmit rotation of the first conveyance roller rotated in the second direction by the separation roller to an arm portion by operation of the torque limiter.

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.