Printhead with pressure-dampening structures
View Patent ↗An inkjet printhead is provided. The printhead comprises a plurality of nozzle assemblies; a nozzle plate covering the plurality of nozzle assemblies; an ink supply system for supplying ink to the plurality of nozzle assemblies, the ink supply system comprising at least one conduit wall defined by part of the nozzle plate; and at least one pressure-dampening structure positioned in the part of the nozzle plate. The pressure-dampening structures dampen ink pressure fluctuations in the ink supply system.
1. An inkjet printhead comprising:
a plurality of nozzle assemblies;
a nozzle plate covering said plurality of nozzle assemblies;
an ink supply system for supplying ink to said plurality of nozzle assemblies, said ink supply system comprising at least one conduit wall defined by part of said nozzle plate; and
at least one pressure-dampening structure comprising a vent defined in said part of said nozzle plate and a flexible membrane sealingly covering said vent,
such that ink pressure fluctuations in said ink supply system are dampened by said pressure-dampening structure.
2. The printhead of claim 1 , wherein said flexible membrane has a Young's modulus of less than 1000 MPa.
3. The printhead of claim 1 , wherein said flexible membrane is a comprised of a polymer layer.
4. The printhead of claim 3 , wherein said polymer layer covers said nozzle plate.
5. The printhead of claim 3 , wherein said polymer layer is hydrophobic.
6. The printhead of claim 3 , wherein said polymer layer is resistant to removal by an oxidizing plasma.
7. The printhead of claim 3 , wherein said polymer layer is comprised of polydimethylsiloxane (PDMS).
8. The printhead of claim 3 comprising a plurality of said pressure-dampening structures, said polymer layer defining a plurality of flexible membranes for sealingly covering each vent.
9. The printhead of claim 1 comprising at least 100 pressure-dampening structures per square cm of said nozzle plate.
10. The printhead of claim 1 , wherein a distance between said pressure-dampening structure and at least one of said nozzle assemblies is less than 100 microns.
11. The printhead of claim 1 , wherein each nozzle assembly of the nozzle assemblies comprises:
a nozzle chamber having a nozzle aperture and an ink inlet defined therein, said ink inlet being in fluid communication with an ink supply channel; and
an actuator for ejection of ink through said nozzle aperture.
12. The printhead of claim 11 , wherein each nozzle chamber is formed on a surface of a printhead substrate, each nozzle chamber comprising a roof spaced apart from said substrate and sidewalls extending between said roof and said substrate, said nozzle aperture being defined in said roof and each roof defining part of the nozzle plate.
13. The printhead of claim 12 , wherein said nozzle chambers are arranged in rows, each row of nozzle chambers having an associated ink conduit extending longitudinally adjacent said row, said ink conduit being defined between said nozzle plate and said substrate, and said ink conduit being defined at least partially by said at least one conduit wall.
14. The printhead of claim 13 , wherein said ink conduit supplies ink to a plurality of said ink chambers via a sidewall ink inlet defined in each nozzle chamber.
15. The printhead of claim 13 , wherein said ink conduit is shared by a pair of rows.
16. The printhead of claim 13 , wherein said ink conduit is connected to one or more ink inlet passages, each ink inlet passage extending from said ink conduit through said substrate, and each ink inlet passage extending substantially perpendicularly with respect to said nozzle plate and said ink conduit.
17. The printhead of claim 16 , wherein each ink inlet passage is aligned with a respective pressure-dampening structure in said nozzle plate.
18. The printhead of claim 16 , wherein each ink inlet passage is connected to an ink supply channel defined in said substrate, said ink supply channel receiving ink from opposite side of said substrate relative to said nozzle assemblies.
19. A printhead integrated circuit comprising:
a substrate;
a plurality of nozzle assemblies formed on said substrate, each nozzle assembly of the plurality of nozzle assemblies having a nozzle aperture and an actuator for ejection of ink through said nozzle aperture;
drive circuity electrically connected to each of said actuators;
a nozzle plate covering said plurality of nozzle assemblies
an ink supply system for supplying ink to said plurality of nozzle assemblies, said ink supply system comprising at least one conduit wall defined by part of said nozzle plate; and
at least one pressure-dampening structure comprising a vent defined in said part of said nozzle plate and a flexible membrane sealingly covering said vent,
such that ink pressure fluctuations in said ink supply system are dampened by said pressure-dampening structure.