A roll sheet, in which a continuous sheet is wound in a roll form, is caused to rotate in a forward direction to supply the sheet to a printing unit. First and second sensors are arranged at positions facing an outer circumferential surface of the roll sheet and deviated in an axis line direction of the roll sheet. Outputs of the first and second sensors are changed in accordance with a distance to a sheet of the roll sheet. A rotation direction of the roll sheet is switched from a forward direction to a reverse direction on the basis of the outputs of the first and second sensors while the roll sheet is being rotated in the reverse direction.

A sheet processing apparatus includes a conveyance portion, a punching portion, a moving portion, a first detecting portion, and a control unit configured to control the conveyance portion, the punching portion and the moving portion, wherein the control unit is configured, for a target position of each of a plurality of holes to be formed to a single sheet, to cause the first detecting portion to execute a detection process, and to execute a moving process of moving the moving portion based on the output value of the first detecting portion corresponding to the target position and a punching process of performing punching to the target position of the sheet by the punching portion after the moving process has been completed.

A post-processing device (200) includes a circulation conveyance path, a zeroth conveyer (R0), and a controller (50). The circulation conveyance path includes a first conveyance path (W1), a second conveyance path (W2), a third conveyance path (W3), a first conveyer (R1), a second conveyer (R2), and a third conveyer (R3). The first and second conveyers convey a preceding sheet (P1) along the first and second conveyance paths. The third conveyer conveys it from the third conveyance path to the first conveyance path. The zeroth conveyer conveys a following sheet (P2) toward the first conveyer. The controller controls the third conveyer to stop the preceding sheet, subsequently controls the zeroth conveyer and the third conveyer to overlay the preceding sheet with the following sheet to form a sheet bundle (Q) having a shift amount (G) between a leading edges of the preceding sheet and the following sheet and strike the leading edges of the preceding sheet and the following sheet against the first conveyer.

An example print medium supplying apparatus includes a print medium transporting device to pick up a print medium loaded in a loading portion and transport the picked-up print medium, a print medium alignment portion to align a leading end of the transported print medium, a first sensor to sense the print medium that passes through a feed roller of the print medium transporting device, and a processor to, based on a measured value with respect to the print medium sensed by the first sensor and a multi-feeding determination reference value corresponding to a sheet of the print medium, detect multi-feeding of the print medium and process the detected multi-feeding by controlling the print medium transporting device and the print medium alignment portion.

An example print medium supplying apparatus includes a print medium transporting device to pick up a print medium loaded in a loading portion and transport the picked-up print medium, a print medium alignment portion to align a leading end of the transported print medium, a first sensor to sense the print medium that passes through a feed roller of the print medium transporting device, and a processor to, based on a measured value with respect to the print medium sensed by the first sensor and a multi-feeding determination reference value corresponding to a sheet of the print medium, detect multi-feeding of the print medium and process the detected multi-feeding by controlling the print medium transporting device and the print medium alignment portion.

A sheet stacking device include a guide unit and a blower. The guide unit receives a downstream end of a sheet in a sheet conveyance direction and guides the sheet downstream in the sheet conveyance direction. The blower blows air toward the sheet guided by the guide unit. A region of the blower from which the air is blown is changeable in response to a size of the sheet.

A conveying device includes a sensor to read a sheet to be conveyed, a first conveyor arranged on an upstream side from the sensor in a sheet conveying direction of the sheet, a second conveyor arranged on a downstream side from the sensor in the sheet conveying direction, and correcting circuitry to correct a distance of the sheet having an error detected when the sensor reads the sheet conveyed by the first conveyor and the second conveyor, to an actual distance. The correcting circuitry uses at least a first correction value correcting a distance read by the sensor when the first conveyor conveys the sheet and a second correction value correcting a distance read by the sensor when the second conveyor conveys the sheet.

A conveying device includes a sensor to read a sheet to be conveyed, a first conveyor arranged on an upstream side from the sensor in a sheet conveying direction of the sheet, a second conveyor arranged on a downstream side from the sensor in the sheet conveying direction, and correcting circuitry to correct a distance of the sheet having an error detected when the sensor reads the sheet conveyed by the first conveyor and the second conveyor, to an actual distance. The correcting circuitry uses at least a first correction value correcting a distance read by the sensor when the first conveyor conveys the sheet and a second correction value correcting a distance read by the sensor when the second conveyor conveys the sheet.

A printing device is provided comprising a camera to capture an image of at least a portion of a print substrate; a controller to determine a location of a portion of a side edge of the print substrate from the image to determine a distance of the print substrate from a predetermined location; and an adjustment apparatus to adjust the entire substrate laterally, relative to the direction of transport of the print substrate, based on the determined location.

A medium transporting apparatus includes a transport belt that has a loop shaped, a cling mechanism that causes the medium to cling to the transport belt, a rotation mechanism that transports the medium by rotating the transport belt, a plurality of detection units that detect an transport direction end of the medium, a controller that corrects a skew of the medium, and a stacker on which the medium transported by the transport belt is stacked, in which the plurality of detection units are arranged at positions that are on an upstream side of the transport belt in the first transport direction and that are different from each other in a width direction, and the controller corrects, according to a result of the detection by the detection units, the skew of the medium in a state of being cling to the transport belt.