Thermal printing apparatus
AssigneeNCR Canada Ltd - NCR Canada Ltee
InventorsTrevor A. Calnek, John E. Bray
Life of this patent
Estimating the term…
Abstract
Thermal printing apparatus includes a magnetic core having a gap, an electromagnetic coil mounted on the core for generating an electromagnetic field in the core and through the gap, a rotatably mounted cylindrical thermal print head having type characters on its periphery and located partially within the gap in the magnetic core, and a mechanism for rotating the print head to locate a selected type character in printing position in cooperative relation to a pressure element. The magnetic field generates circulating currents in the print head for heating it to a temperature necessary for causing heat-sensitive ink to be transferred from a ribbon to a record medium, both of which are positioned between the print head and the pressure element.
Claims3
Printing apparatus comprising
- support means;
- a magnetic core having a gap therein and having a slot in said core which extends through the gap, and mounted on said support means;
- a coil mounted on said core and capable of generating a magnetic field in said core which extends through said gap;
- a rotatable cylindrical thermal print head including an annular element of high conductivity material having a plurality of print characters arranged on the periphery thereof and fixed to a central hub of nonconductive material, said print head being located at least partially within the gap of said magnetic core;
- shaft means disposed within the slot in said magnetic core for rotatably mounting said print head on said support means in operative relation to the gap of said magnetic core;
- motor means mounted on said support means and operatively coupled to said shaft means for moving said print head to position a selected character for printing;
- and
- means to energize said coil to generate an electromagnetic field in said magnetic core, said electromagnetic field generating circulating currents in said annular element to heat said print head to a temperature suitable for thermal printing.
Dependencies are inferred from the claim text.