A printing apparatus 10 includes support member 12 that supports a core body Ra of a roll medium R, a transport mechanism 17 that transports the print medium S drawn out from the roll medium R, a first accommodation sidewall 27 and a second accommodation sidewall 28 arranged in a width direction, a print head 22, and a trailing edge detection section 60 that detects that all of the print medium S that is drawable out from the roll medium R has been drawn out by the transport mechanism 17, wherein the first accommodation sidewall 27 has groove 50, and the roll medium R is accommodated in an accommodation section 11 by engaging the support member 12 with the groove 50 and the trailing edge detection section 60 detects that the support member 12 is separated from an engagement surface 52 of the groove 50.

A rebel printer includes an estimation unit that estimates a remaining amount of a roll sheet based on R=PF/(π.Math.REV) (Equation (1)). A first measurement unit resets the measured cumulative rotation amount each time the remaining amount of the roll sheet is estimated or each time the remaining amount of the roll sheet is estimated multiple times, A second measurement unit resets the measured cumulative conveyance amount each time the remaining amount of the roll sheet is estimated or each time the remaining amount of the roll sheet is estimated multiple times, and the estimation unit performs a filter process on A diameter of the roll sheet calculated using the Equation (1), and estimates the diameter subjected to the filter process as the remaining amount of the roll sheet.

According to an embodiment, a printer includes a drop portion that catches, in a case where a diameter of a roll of paper stored in a holder becomes small, the roll of paper that falls from the holder. The printer further includes a plurality of support rollers that are arranged so as to sandwich an inlet of the drop portion and rotatably support the roll of paper PR stored in the holder. At least one of the plurality of support rollers is a short-width roller whose width in an axial direction of a shaft is shorter than a paper width of the roll of paper PR, and a void is provided at a non-shaft arrangement part provided at an extension portion of the short-width roller in the axial direction.

A printing apparatus includes a roll paper compartment 15 having a first placement surface 27 on which an outer peripheral surface Ra of a roll paper R around which a recording paper P is wound is placed and accommodating the roll paper R, a thermal head 67 performing printing on the recording paper P pulled out from the roll paper R accommodated in the roll paper compartment 15, a first projecting/retracting portion 77 provided to be configured to project from or retract into the first placement surface 27, pressed by the roll paper R of which the outer peripheral surface Ra is placed on the first placement surface 27 and retracting into the first placement surface 27 when a diameter of the roll paper R is larger than a predetermined diameter, and released from the pressure by the roll paper R and protruding from the first placement surface 27 when the diameter of the roll paper R is smaller than the predetermined diameter, and a detection section detecting projection and retraction of the first projecting/retracting portion 77.

A printing apparatus includes a first projecting/retracting portion located at a first pressing position when a diameter of a roll paper R is larger than a first diameter and located at a first release position when the diameter of the roll paper R is smaller than the first diameter in a case where the printing apparatus is installed in a first posture, a second projecting/retracting portion located at a second pressing position when the diameter of the roll paper R is larger than a second diameter and located at a second release position when the diameter of the roll paper R is smaller than the second diameter in a case where the printing apparatus is installed in a second posture, and a detection section having a single sensor and detecting a displacement of the first projecting/retracting portion and a displacement of the second projecting/retracting portion by the sensor.

A sheet feed cassette monitor includes an actuator with another end portion, a detecting circuit, a plurality of protrusions, a signal monitoring circuit, and a signal determining circuit. When the one end portion is in contact with a paper sheet, the other end portion swings in a first direction. When the one end portion is not in contact with the paper sheet, the other end portion swings in a second direction opposite direction to the first direction. The detecting circuit detects the swinging of the other end portion on the actuator. The plurality of protrusions are convexly installed in an asymmetric manner with respect to a putting-in/taking-out direction of the feed cassette. The signal determining circuit determines a presence/absence state of the paper sheet housed in the sheet feed cassette and an open/close state of the sheet feed cassette based on a pattern of change in the monitored signal.

According to the embodiment, a printer includes a feeding device, a mark detector device, and a controller device. The feeding device feeds an elongated recording medium. A bar-shape mark having a predetermined length is successively formed from a rear end of the recording medium. The mark detector device detects presence/absence of the mark on a feeding path of the feeding device. The controller device recognizes that the recording medium is in a near-end status based on a mark detection result of the mark detector device.

A printer includes a printer body and a lid. The printer body includes a recording paper holder configured to accommodate a roll of recording paper and a projection provided on a bottom surface of the recording paper holder that contacts the recording paper. The lid is attached to the printer body to be opened and closed relative to the printer body.

In some examples, a non-transitory machine readable medium can include instructions executable by a processing resource to assert a low print media level notification responsive to determination that a first amount of print media in a media receptacle of an imaging device is less than a set value, detect a second amount of print media in the media receptacle of the imaging device, compare the detected second amount of print media to a print media threshold that is based on the set value and a selectable print media value, and maintain the low print media level notification responsive to a determination that the detected second amount of print media is less than the print media threshold.

An image forming system includes an image forming apparatus, a first conveyance path, a sheet feeding unit, a sheet post-processing unit, and a controller. The image forming apparatus has a first feed portion, and an image forming portion. The sheet feeding apparatus has a sheet stacking portion, a second feed portion, a relay conveyance portion, and a remaining amount detecting portion. When, during continuous printing, the existing number of recording sheets present in a conveyance passage from a confluence portion to the first feed portion is more than the constituting number of recording sheets contained in one bundle of sheets and in addition the sensing result of the remaining amount sensor is equal to or less than a predetermined amount, the controller controls first feed portion such that the existing number of the recording sheets is less than the constituting number of recording sheets.