Multi-nozzle electrohydrodynamic printing

Patent metadata

Field	Value
Publication number	US-11370219-B2
Application number	US-202017017644-A
Country	US
Kind code	B2
Filing date	Sep 10, 2020
Priority date	Sep 10, 2019
Publication date	Jun 28, 2022
Grant date	Jun 28, 2022

Abstract

An electrohydrodynamic print head includes a plurality of nozzles and a common electrode. Separately controllable electrostatic fields between the common electrode and each nozzle are provided. The common electrode can also shield adjacent electrostatic fields from each other. Each nozzle can be associated with separately controllable gas flow fields and separately back pressures. The print head enables simultaneous e-jet printing of different printing fluids and/or different resolutions. The print head may be part of a printing system with interchangeable cartridges. Each cartridge has multiple nozzles, and printing fluid extraction parameters can be made separately controllable for each nozzle.

First claim

The invention claimed is:

1. An electrohydrodynamic print head comprising a plurality of nozzles and a common electrode at a fixed position relative to the nozzles, wherein the print head is configured to provide separately controllable electrostatic fields between the common electrode and each nozzle, the print head further comprising:
a carrier;
a printer cartridge that includes a housing, the plurality of nozzles, and the common electrode, wherein the carrier supports the printer cartridge for relative movement over a printing surface,
wherein the housing provides connectivity for at least one of the following: a voltage source for an extraction electrode, a pressurized gas source for a gas flow field in which extracted printing fluid travels toward the printing surface, and a backpressure source for application to printing fluid in the nozzles, and
wherein the printer cartridge is removably supported by the carrier for replacement with a different printer cartridge comprising a housing with the same connectivity.

2. The print head of claim 1 , wherein the common electrode includes a plurality of extraction openings, each extraction opening being aligned with one of the nozzles such that printing fluid extracted from each nozzle passes through the respective extraction opening for deposition on the printing surface.

3. The print head of claim 1 , wherein the common electrode extends between adjacent nozzles in an axial direction of the nozzles to thereby shield the separately controllable electrostatic fields from each other.

4. The print head of claim 1 , wherein the print head is configured to provide said gas flow field in a direction toward the printing surface.

5. The print head of claim 1 , wherein the print head is configured to provide a plurality of separately controllable gas flow fields, each gas glow field flowing along one of the nozzles and in a direction toward a printing surface such that printing fluid extracted from each nozzle travels toward the printing surface in the respective gas flow field.

6. The print head of claim 1 , further comprising a plurality of extraction electrodes, each extraction electrode being arranged to provide one of the separately controllable electrostatic fields when a voltage potential relative to the common electrode is applied to the respective extraction electrode.

7. The print head of claim 6 , wherein each nozzle comprises one of the extraction electrodes.

8. The print head of claim 1 , wherein the print head is configured to provide separately controllable back pressure on a printing fluid in each nozzle.

9. The print head of claim 1 , wherein each nozzle contains a different printing fluid.

10. The print head of claim 1 , wherein each nozzle contains the same printing fluid.

11. The print head of claim 1 , wherein each nozzle is spaced from the common electrode by a different amount in an axial direction.

12. The print head of claim 1 , wherein each nozzle includes an extraction opening at a tip of the nozzle, each extraction opening having a different size.

13. An electrohydrodynamic printing system comprising the print head of claim 1 and a movement system configured to provide said relative movement of each printer cartridge over a printing surface.

14. An electrohydrodynamic printing system, comprising:
a plurality of printer cartridges, each printer cartridge comprising a housing, a plurality of nozzles, and a common electrode at a fixed position relative to the nozzles; and
a carrier configured to interchangeably support each one of the printer cartridges individually for relative movement over a printing surface,
wherein the housing of each printer cartridge provides connectivity for at least one of the following when the corresponding printer cartridge is being supported by the carrier: a voltage source for an extraction electrode of the cartridge, a pressurized gas source for a gas flow field in the cartridge in which extracted printing fluid travels toward the printing surface, and a backpressure source for application to printing fluid in the nozzles of the cartridge, and
wherein the printing system is configured to provide separately controllable electrostatic fields between the common electrode and each nozzle of the same cartridge when the respective cartridge is being supported by the carrier.

15. The printing system of claim 14 , wherein each nozzle of each cartridge is configured for a respective printing fluid, an extraction opening of each nozzle and a distance of each nozzle from the common electrode being a function of the respective printing fluid, and at least one of the nozzles of one of the cartridges being configured for a different printing fluid than another one of the nozzles of one of the cartridges.

16. The printing system of claim 14 , wherein a first one of the cartridges is configured for use with a first printing fluid in each nozzle and a second one of the cartridges is configured for use with a different second printing fluid in each nozzle.

17. The printing system of claim 14 , wherein one of the nozzles of one of the cartridges is configured for use with a different printing fluid than another one of the nozzles of the same cartridge.

18. The printing system of claim 14 , wherein the common electrode of at least one of the cartridges includes a plurality of extraction openings, each extraction opening being aligned with a respective one of the nozzles such that printing fluid extracted from each nozzle passes through the respective extraction opening for deposition on the printing surface.

19. The printing system of claim 14 , wherein the system is configured to provide a plurality of separately controllable gas flow fields associated with each cartridge, each separately controllable gas flow field flowing along a respective one of the nozzles and in a direction toward the printing surface such that printing fluid extracted from each nozzle travels toward the printing surface in the respective gas flow field.

20. The printing system of claim 14 , wherein at least one of the cartridges:
contains a different printing fluid in each nozzle,
contains the same printing fluid in each nozzle,
includes a different amount of spacing between the common electrode and each nozzle, or
includes a differently sized extraction opening at a tip of each nozzle.

Assignees

• Univ Michigan Regents

Inventors

• Tse Lai Yu Leo
• Barton Kira
• Mcmillan Ethan John

Classifications

• B41J2/085 Primary

  Charge means, e.g. electrodes · CPC title

• B41J2/06

  by electric or magnetic field · CPC title

• B41J2/10 Primary

  magnetic field-control type · CPC title

• B41J2202/02

  Air-assisted ejection · CPC title

• B41J2/072

  by thermal compensation · CPC title