Disclosed herein is a method of managing a printing apparatus including a thermal print head. The method of managing a printing apparatus includes: starting, by the controller of a printing apparatus, the cleaning of a thermal print head when a predetermined condition is satisfied; selecting, by the controller, a cleaning method based on at least one the satisfied condition and previously stored information; and cleaning, by the controller, the thermal print head by driving at least one of heating elements, included in a plurality of recording elements constituting the thermal print head, according to the selected cleaning method.

Disclosed herein is a method of managing a printing apparatus including a thermal print head. The method of managing a printing apparatus includes: starting, by the controller of a printing apparatus, the cleaning of a thermal print head when a predetermined condition is satisfied; selecting, by the controller, a cleaning method based on at least one the satisfied condition and previously stored information; and cleaning, by the controller, the thermal print head by driving at least one of heating elements, included in a plurality of recording elements constituting the thermal print head, according to the selected cleaning method.

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.

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.

Disclosed herein is a method of managing a printing apparatus including a thermal print head. The method of managing a printing apparatus includes: starting, by the controller of a printing apparatus, the cleaning of a thermal print head when a predetermined condition is satisfied; selecting, by the controller, a cleaning method based on at least one the satisfied condition and previously stored information; and cleaning, by the controller, the thermal print head by driving at least one of heating elements, included in a plurality of recording elements constituting the thermal print head, according to the selected cleaning method.

A roller module includes a roller, a magnetic bearing, a permanent magnet, at least one pair of magnetic coring, and a plurality of gap sensors. The roller has a protrusion and has a cylindrical shape. The protrusion is formed at both outer surfaces of the roller with a stepped portion and has the cylindrical shape. The magnetic bearing is formed at the roller. The permanent magnet is formed at the roller. At least one pair of magnetic coring covers an outer circumference of the protrusion. The gap sensors are formed along an axial direction and a radial direction of the roller.

A roller module includes a roller, a magnetic bearing, a permanent magnet, at least one pair of magnetic coring, and a plurality of gap sensors. The roller has a protrusion and has a cylindrical shape. The protrusion is formed at both outer surfaces of the roller with a stepped portion and has the cylindrical shape. The magnetic bearing is formed at the roller. The permanent magnet is formed at the roller. At least one pair of magnetic coring covers an outer circumference of the protrusion. The gap sensors are formed along an axial direction and a radial direction of the roller.

Disclosed herein is a method of managing a printing apparatus including a thermal print head. The method of managing a printing apparatus includes: starting, by the controller of a printing apparatus, the cleaning of a thermal print head when a predetermined condition is satisfied; selecting, by the controller, a cleaning method based on at least one the satisfied condition and previously stored information; and cleaning, by the controller, the thermal print head by driving at least one of heating elements, included in a plurality of recording elements constituting the thermal print head, according to the selected cleaning method.

Disclosed herein is a method of managing a printing apparatus including a thermal print head. The method of managing a printing apparatus includes: starting, by the controller of a printing apparatus, the cleaning of a thermal print head when a predetermined condition is satisfied; selecting, by the controller, a cleaning method based on at least one the satisfied condition and previously stored information; and cleaning, by the controller, the thermal print head by driving at least one of heating elements, included in a plurality of recording elements constituting the thermal print head, according to the selected cleaning method.

An adjuster for first and second print rollers carried on respective first and second supports has a first spindle extending along and rotatable about an axis between the supports and formed with a pair of axially spaced screwthreads of the same hand but of different pitches. One of the screwthreads is threaded into the first support and the other into a first nut rotatable about the axis and axially fixed in the second support. A mechanism serves for either arresting the nut against rotation relative to the second support and or rotating the nut relative to the second support.