A sheet conveying device includes a conveying roller configured to convey a sheet and a plurality of driven rotating units. The conveying roller includes a plurality of roller portions disposed at positions opposite to the driven rotating units. Each of the roller portions has three or more annular grooves arranged side by side. Each of the driven rotating units includes three or more driven rotating bodies that are disposed at positions opposite to the annular grooves, respectively. A plurality of convex portions and a plurality of concave portions are alternately provided on an outer edge of each of the driven rotating bodies. The driven rotating bodies include two first rotating bodies positioned at both ends and one or more second rotating bodies located between the first rotating bodies and having an outer diameter smaller than the outer diameter of the first rotating bodies.

A sheet conveying device includes a conveying roller configured to convey a sheet and a plurality of driven rotating units. The conveying roller includes a plurality of roller portions disposed at positions opposite to the driven rotating units. Each of the roller portions has three or more annular grooves arranged side by side. Each of the driven rotating units includes three or more driven rotating bodies that are disposed at positions opposite to the annular grooves, respectively. A plurality of convex portions and a plurality of concave portions are alternately provided on an outer edge of each of the driven rotating bodies. The driven rotating bodies include two first rotating bodies positioned at both ends and one or more second rotating bodies located between the first rotating bodies and having an outer diameter smaller than the outer diameter of the first rotating bodies.

A system and method for feeding a ribbon of un-lined label stock to a printer includes first and second, abutting rollers that cooperatively remove label stock from a roll. An optical sensor is disposed in a ribbon path between the rollers and the printer. The optical sensor determines a slackness level of the ribbon between rollers and the printer. Speed of a drive roller drive motor is increased when the slackness level is below a prescribed threshold. Speed of the drive roller motor is decreased when the slackness level is above a prescribed threshold.

Disclosed herein is a device for fixing a platen roller for a printing apparatus. The device includes: a fixing frame installed in the housing of the printing apparatus; roller bearings respectively coupled to both ends of the platen roller in the longitudinal direction of the platen roller, and configured to allow the platen roller to be rotated; bearing holders installed on the fixing frame, and configured to provide coupling portions for the roller bearings and to allow the roller bearings to enter and exit in a horizontal direction corresponding to the longitudinal direction of the platen roller; and a locking part configured to fix the platen roller and the roller bearings to the bearing holders in the state of preventing the horizontal movement of the platen roller and the roller bearings while restraining at least one of the both ends of the platen roller to the bearing holder.

A print device comprises a media pickup assembly to feed print media, from a print media stack of an input tray, into a media loading path for printing. The media pickup assembly (106) includes a pickup roller (110) mounted on a rotatable shaft (108) and may include an outer surface (112) to be in contact with the print medium and a slot (114) comprising lateral walls (404) extending from the outer surface towards a central longitudinal axis of the pickup roller. Each lateral wall has an edge meeting the outer surface (112). The edge (408) creates a surface contact between the print media and the pickup roller, to allow the pickup roller (110) to push the print media into the media loading path. A distance between the edge (408) of one lateral wall (404-1) and the edge of another lateral wall (404-2) is in a range of about 2 mm to 3 mm. The distance defines a width of the slot (114).

A print device comprises a media pickup assembly to feed print media, from a print media stack of an input tray, into a media loading path for printing. The media pickup assembly (106) includes a pickup roller (110) mounted on a rotatable shaft (108) and may include an outer surface (112) to be in contact with the print medium and a slot (114) comprising lateral walls (404) extending from the outer surface towards a central longitudinal axis of the pickup roller. Each lateral wall has an edge meeting the outer surface (112). The edge (408) creates a surface contact between the print media and the pickup roller, to allow the pickup roller (110) to push the print media into the media loading path. A distance between the edge (408) of one lateral wall (404-1) and the edge of another lateral wall (404-2) is in a range of about 2 mm to 3 mm. The distance defines a width of the slot (114).

A heating roller for a wet ink-based image forming apparatus includes a roller having a contact surface to contact a print medium having wet ink deposited thereon by wet ink-based image forming apparatus. The heating roller conductively heats the print medium and dries and flattens the print medium. The heating roller includes a heating element embedded along the roller. The heating element rotates with the roller as the roller rotates. The heating element generates and conducts heat to the contact surface so as to conductively heat the print medium through the contact surface when the contact surface contacts the print medium.

A heating roller for a wet ink-based image forming apparatus includes a roller having a contact surface to contact a print medium having wet ink deposited thereon by wet ink-based image forming apparatus. The heating roller conductively heats the print medium and dries and flattens the print medium. The heating roller includes a heating element embedded along the roller. The heating element rotates with the roller as the roller rotates. The heating element generates and conducts heat to the contact surface so as to conductively heat the print medium through the contact surface when the contact surface contacts the print medium.

In order to enable a sheet to be properly guided to a nip portion in performing folding processing, a sheet processing apparatus for performing folding processing on a sheet is provided with a rotating body pair which nips the sheet by a nip portion to rotate, and thereby draws the sheet to perform folding processing, a folding blade that pushes the sheet to the nip portion of the rotating body pair, and a blade guide member including a guide portion for pushing the sheet to the nip portion when the folding blade pushes the sheet to the nip portion, where the folding blade and blade guide member are relatively shifted so that a distance from a push front edge portion to the guide portion when the folding blade pushes the sheet to the nip portion is longer than a distance from the front edge portion to the guide portion.

In order to enable a sheet to be properly guided to a nip portion in performing folding processing, a sheet processing apparatus for performing folding processing on a sheet is provided with a rotating body pair which nips the sheet by a nip portion to rotate, and thereby draws the sheet to perform folding processing, a folding blade that pushes the sheet to the nip portion of the rotating body pair, and a blade guide member including a guide portion for pushing the sheet to the nip portion when the folding blade pushes the sheet to the nip portion, where the folding blade and blade guide member are relatively shifted so that a distance from a push front edge portion to the guide portion when the folding blade pushes the sheet to the nip portion is longer than a distance from the front edge portion to the guide portion.