A plurality of marks (11) equidistantly provided on both side edge parts (1a) of a long medium (1), a plurality of first indicator holes (12) equidistantly given on at least one of the side edge parts (1a), and a plurality of second indicator holes (13) given on at least one of the side edge parts (1a) on a straight line different from a row of the first indicator holes (12) at spacings shorter than spacings of the first indicator holes (12) are provided, and the second indicator holes (13) are each provided to a side of a trailing-end mark (11b), and each gradually comes closer to a leading-end mark (11a) as the long medium (1) runs toward a trailing end.

A sheet delivery system includes: an end section detector which detects a position of an end section of a sheet; an operation robot which holds the end section of the sheet and which conveys the end section of the sheet to a joining unit; a roll driving motor which rotationally drives the standby-side original material roll around a central axis thereof; and a suction roller which is capable of coming into rolling contact with an outer peripheral surface of the standby-side original material roll, and which includes an outer peripheral surface capable of suctioning the end section of the sheet in order to separate the end section of the sheet from the standby-side original material roll. The end section detector is attached at a position which enables detection of the end section of the sheet separated from the standby-side original material roll by the suction roller.

A sheet feeding device that performs sheet feeding by feeding out and cutting a continuous medium includes a carrying part that carries the medium, a detection part that detects a leading edge of the medium and a length over which the medium has been carried, a trailing edge detection part that detects a trailing edge of the medium specified by a user; and a cutting part arranged between the detection part and the trailing edge detection part, and is capable of cutting the medium or forming cuts in the medium (a perforation process). When a minimum length of the medium that is carried by the carrying part is L2, a length from the detection part to the trailing edge detection part is L3, and a length of the medium that is specified by the user is L4, when the trailing edge of the medium is detected, and when L4<L3<L2+L4 is satisfied, the detection part detects a position is L4, and the cutting part forms cuts in the medium at the position.

In an image forming apparatus that the present invention is concerning to, rolled paper is conveyed in a forward conveyance direction for a predetermined period of time, when it is detected that an amount of the rolled paper rolled around a core pipe equals a predetermined amount or less. On the basis of the detection result, a CPU determines the rolled state of the rolled paper with respect to the core pipe and conveys the rolled paper in the forward conveyance direction or a reverse conveyance direction according to the rolled state.

A paper feeding device for rotating a roll paper forward and backward to feed the roll paper includes a roller, a sensor, a support, and processing circuitry. The sensor detects a level difference at an end of the roll paper. On the supports, the sensor and the roller are arranged at positions offset from each other in a circumferential direction of the roll paper with respect to a center of the roll paper. The support supports the sensor and the roller to abut on a surface of the roll paper. The processing circuitry controls rotation of the roll paper based on a sensor signal output from the sensor. The processing circuitry causes the roll paper to rotate in a paper feeding direction, and compares an inclination of a change in the sensor signal with a threshold value to detect a paper tube of the roll paper.

A sensor assembly configured to detect rolled stock on a core includes a sensor configured to detect a first roll of stock unwinding from a core, the stock unwinding from the core of the first roll is supplied as a web of stock, wherein in response to the sensor detecting a first detection configuration, the sensor takes no action and continues to detect the first roll, and wherein in response to the sensor detecting a second detection configuration, the sensor provides a command to a splice assembly to transition to a second roll of stock to replace the first roll of stock.

A sensor assembly configured to detect rolled stock on a core includes a sensor configured to detect a first roll of stock unwinding from a core, the stock unwinding from the core of the first roll is supplied as a web of stock, wherein in response to the sensor detecting a first detection configuration, the sensor takes no action and continues to detect the first roll, and wherein in response to the sensor detecting a second detection configuration, the sensor provides a command to a splice assembly to transition to a second roll of stock to replace the first roll of stock.

A sheet feeder includes a support to support a roll sheet winding a sheet, a sensor that is at a first position on the support and contacts a surface of the roll sheet to detect a level difference at a trailing edge of the roll sheet and output a first signal and a second signal, a roller that is at a second position different from the first position in a circumferential direction of the roll sheet on the support and contacts the surface of the roll sheet to guide the roll sheet, and circuitry to cause the roll sheet to rotate in a sheet feeding direction to feed the sheet, and detect the trailing edge of the roll sheet based on the first signal output from the sensor, and the second signal output from the sensor.