Low voltage nozzle assembly for an inkjet printer
View Patent ↗A nozzle assembly for an inkjet printhead is disclosed. The nozzle assembly includes an inkjet nozzle having an actuator for ejecting an ink droplet from the inkjet nozzle when a resistive element of the actuator is heated by an electrical current. A drive transistor provides an energy pulse to the resistive element of the actuator, and control logic controls the drive transistor. The voltage of the energy pulse is less than 10 V.
1. A nozzle assembly for an inkjet printhead, said nozzle assembly comprising:
an inkjet nozzle having an actuator for ejecting an ink droplet from said inkjet nozzle when a resistive element of said actuator is heated by an electrical current;
a drive transistor for providing an energy pulse to said resistive element of said actuator; and
control logic for controlling said drive transistor,
wherein the voltage of said energy pulse is less than 10 V.
2. The nozzle assembly as claimed in claim 1 , wherein said drive transistor, control logic and said inkjet nozzle covers an area of less than 20,000 μm 2 .
3. The nozzle assembly as claimed in claim 1 , wherein the diameter of said ink droplet is less than 20 μm.
4. The nozzle assembly as claimed in claim 1 , wherein an aperture of said inkjet nozzle through which said ink droplet is ejected has a diameter of less than 15 μm.
5. The nozzle assembly as claimed in claim 1 , wherein the velocity of said ink droplet is less than 8 m/s.
6. The nozzle assembly as claimed in claim 1 , wherein the volume of said droplet is less than 3 pl.
7. The nozzle assembly as claimed in claim 1 , wherein the energy of said energy pulse is less than 1 μJ.
8. The nozzle assembly as claimed in claim 1 , wherein said drive transistor and control logic are formed on a silicon substrate, and said inkjet nozzle is formed over at least one of said drive transistor and control logic.
9. The nozzle assembly as claimed in claim 1 , wherein said actuator develops a pressure of less than 100 kPa within said inkjet nozzle.
10. The nozzle assembly as claimed in claim 1 , wherein a channel length of said drive transistor is less than 1 μm.
11. A printhead comprising a plurality of nozzle assemblies as defined in claim 1 , wherein nozzles are spaced from other nozzles ejecting ink of a same color by less than 25 μm in a direction transverse to the direction of movement of a print media upon which ink is ejected.
12. The printhead defined in claim 11 comprising at least 2000 nozzles fabricated on a single monolithic wafer.
13. A printhead comprising a plurality of nozzle assemblies as defined in claim 1 , wherein nozzles are spaced from other nozzles ejecting ink of a different color by less than 400 microns.