INK JET PRINTER AND METHOD FOR HEAT-INSULATING CONTROL OF PRINTING HEAD THEREFOR

摘要

PROBLEM TO BE SOLVED: To realize a low cost ink jet printing system high in reliability even in low temp. environment and reduced in the change of emitting quantity during printing. SOLUTION: A drive signal is supplied to the energy applying means (emitting heater) arranged in the liquid passage of an ink jet head to apply heat energy to ink to form a bubble and the bubble is allowed to communicate with the open air from an emitting orifice to emit the ink from the emitting orifice to perform printing. A special heater is not provided in heat insulating control and drive pulses having time width insufficient to generate the bubble in the ink are supplied to the emitting heater during a non-printing operation period in proper duties [(a)-(d)] corresponding to a head temp. condition to allow the emitting heater to generate heat to perform the heat insulation of the head. By this constitution, a low cost thermal ink jet printing system is provided not accompanied by the change of emitting quantity during printing.