Energy supply for thermal print head of facsimile machine - uses measurement of supply voltage to heating element on print head to determine duration of supply and thus temperature

摘要

The supply to the thermal print head (3) connects a heating element (2) on the head (3) to a source of electric supply (4), for a period determined by the temperature of the head. The activation period starts just before the start of printing, and just after the start of printing of a line the duration of the activation is determined as a function of the voltage supplied by the source. The operation of the print head is controlled by a circuit that processes the measurement signals and determines duration from this data. ADVANTAGE - Removes need for voltage regulator, increasing efficiency in control of temperature of print head, especially for battery powered facsimile machines.