Ink jet printer having driver circuit for generating warming and firing pulses for heating elements

摘要

An ink jet printing apparatus is provided comprising a print cartridge including at least one resistive heating element in at least one ink-containing chamber having an orifice. The apparatus further includes a driver circuit, electrically coupled to the print cartridge, for applying to the resistive heating element warming and firing pulses separated by a delay period. The warming pulse causes the resistive heating element to warm a portion of the ink adjacent to the heating element and the firing pulse causes the resistive heating element to produce a vapor bubble in the chamber which causes a droplet of ink to be ejected from the chamber orifice.