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

Example implementations relate to adjusting print medium retrieval. For example, a system may include a printing device that may have a pick roller attached to a pick arm and a servomotor to apply torque to the pick roller. The system may further include a controller associated with the servomotor to determine a measured position of the servomotor relative to an intended position of the servomotor in a particular time frame during the print medium retrieval. The controller may further determine adjustment of the print medium retrieval based on comparison of a pulse width modulation (PWM) magnitude in adjacent time frames.

Example implementations relate to adjusting print medium retrieval. For example, a system may include a printing device that may have a pick roller attached to a pick arm and a servomotor to apply torque to the pick roller. The system may further include a controller associated with the servomotor to determine a measured position of the servomotor relative to an intended position of the servomotor in a particular time frame during the print medium retrieval. The controller may further determine adjustment of the print medium retrieval based on comparison of a pulse width modulation (PWM) magnitude in adjacent time frames.

In one example, a torque control system for a sheet media pick mechanism to move a top sheet of media from a stack of media sheets into a nip between a pick roller and a separator roller. The torque control system includes a sensor to sense a number of consecutive pick failures and a controller operatively connected to the sensor to reduce a torque applied to the separator roller during a pick attempt after each pick failure in an amount corresponding to the number of consecutive pick failures sensed by the sensor.

In one example, a torque control system for a sheet media pick mechanism to move a top sheet of media from a stack of media sheets into a nip between a pick roller and a separator roller. The torque control system includes a sensor to sense a number of consecutive pick failures and a controller operatively connected to the sensor to reduce a torque applied to the separator roller during a pick attempt after each pick failure in an amount corresponding to the number of consecutive pick failures sensed by the sensor.

A medium processing device includes a processor, a feed roller, a motor, a motive force transmission gear that transmits motive force of the motor to the feed roller, a switching unit that is configured including a main gear and a sub gear that meshes with the main gear and moves in planetary motion around the main gear, and that switches accompanying rotation direction switching of the main gear between a meshed state and a disengaged state between the sub gear and the motive force transmission gear, a load detection unit that detects load of the motor, and a controller. The controller controls the motor and the processor according to the load detected by the load detection unit at switching of the sub gear from the disengaged state to the meshed state.

A medium processing device includes a processor, a feed roller, a motor, a motive force transmission gear that transmits motive force of the motor to the feed roller, a switching unit that is configured including a main gear and a sub gear that meshes with the main gear and moves in planetary motion around the main gear, and that switches accompanying rotation direction switching of the main gear between a meshed state and a disengaged state between the sub gear and the motive force transmission gear, a load detection unit that detects load of the motor, and a controller. The controller controls the motor and the processor according to the load detected by the load detection unit at switching of the sub gear from the disengaged state to the meshed state.

A web transporting method includes a drive roller (Gd), N (where N is an integer of 1 or greater) driven rollers (Gn) which nip a wound portion of a web between the drive roller and the driven rollers, and a tension application unit which applies a tension Tl to a portion of the web which is one side of the wound portion and applies a tension Th which is higher than the tension Tl to a portion of the web which is opposite the one side of the wound portion, in which an angle 0, an angle (n), a load P(n), a static friction coefficient 0, and a static friction coefficient (n) satisfy a predetermined relational expression (expression 1).

A web transporting method includes a drive roller (Gd), N (where N is an integer of 1 or greater) driven rollers (Gn) which nip a wound portion of a web between the drive roller and the driven rollers, and a tension application unit which applies a tension Tl to a portion of the web which is one side of the wound portion and applies a tension Th which is higher than the tension Tl to a portion of the web which is opposite the one side of the wound portion, in which an angle 0, an angle (n), a load P(n), a static friction coefficient 0, and a static friction coefficient (n) satisfy a predetermined relational expression (expression 1).

A method is provided for supplying a corrugated board article or a paperboard sheet article from a feeder apparatus for receipt by an article processing host machine. The method includes feeding the article to a feeder apparatus including a sheet supporting feed table surface having a feed end and a delivery end, feed elements, and a control surface selectively movable between a covering state and an exposing state. In the exposing state the feed elements are exposed to contact and drive the article along the sheet supporting feed table. The control surface is selectively movable to an angled state to selectively angle the control surface to consecutively conceal the respective feed elements as the article moves over the feed elements.