Arrayed electrohydrodynamic printhead without extraction electrodes

Patent metadata

Field	Value
Publication number	US-11850849-B2
Application number	US-202218016356-A
Country	US
Kind code	B2
Filing date	Sep 15, 2022
Priority date	Sep 15, 2021
Publication date	Dec 26, 2023
Grant date	Dec 26, 2023

Abstract

An arrayed electrohydrodynamic printhead without the extraction electrodes is provided. A printhead is formed by an ink cartridge, a flow channel plate, a nozzle plate, a control electrode layer. The ink cartridge includes an ink inlet, an ink outlet, an installation hole, a flow channel layer inlet, flow channel layer outlet. The flow channel plate has the functions of guiding the ink to flow into the nozzle plate and increasing the potential difference between the nozzles, and includes a flow channel inlet, a flow channel outlet, a drainage channel, and a microfluidic channel. A body of the nozzle plate includes nozzles and nozzle electrodes. The microfluidic channel forms a voltage division unit between each nozzle, so that the voltage on the triggered nozzle is dispersed in the flow channel without affecting other nozzles, and independent and controllable injection of each nozzle is thereby achieved.

First claim

What is claimed is:

1. An arrayed electrohydrodynamic printhead without extraction electrodes, comprising an ink cartridge, a flow channel plate, and a nozzle plate, wherein
the flow channel plate is disposed at a bottom portion of the ink cartridge, and a flow channel cavity thereof comprises a plurality of microfluidic channels communicating with the ink cartridge,
the nozzle plate is disposed at a bottom portion of the flow channel plate, the nozzle plate comprises a plurality of nozzles and nozzle electrodes assembled therewith, the plurality of nozzles are correspondingly disposed and communicating with the plurality of microfluidic channels, and ink flows from the ink cartridge through the flow channel cavity and is ejected from the nozzles,
the microfluidic channels between different nozzles and the ink in the microfluidic channels form a plurality of voltage division units, the triggered nozzles, the voltage division units, and the non-triggered nozzles form a voltage division circuit when a voltage is applied to the nozzles, and by adjusting a resistance value of the voltage division units or a grounding resistance value of the non-triggered nozzles, a potential difference between the triggered nozzles and the non-triggered nozzles is changed, so that a difference between the applied voltage and the potential difference is less than a onset threshold voltage, and that the nozzles are independently controlled,
wherein the adjustment of the resistance of the voltage division units is implemented by adjusting an electrical resistivity of the ink and/or a geometric dimension of the microfluidic channels.

2. The arrayed electrohydrodynamic printhead without extraction electrodes according to claim 1 , wherein the flow channel cavity further comprises a flow channel inlet, a flow channel outlet, and a drainage channel, the flow channel inlet and the flow channel outlet are located at both ends of the flow channel cavity, the transition channel is disposed between the flow channel inlet and the plurality of microfluidic channels and between the flow channel outlet and the plurality of microfluidic channels and is configured to evenly guide the ink in the ink cartridge into the microfluidic channels or to guide the ink in the microfluidic channels into the ink cartridge.

3. The arrayed electrohydrodynamic printhead without extraction electrodes according to claim 2 , wherein the plurality of microfluidic channels comprise a tree-like bifurcated structure distribution, a bifurcated structure distribution, and a strip-shaped structure distribution.

4. The arrayed electrohydrodynamic printhead without extraction electrodes according to claim 3 , wherein the ink cartridge comprises a cartridge body and installation holes, slots, an ink inlet, an ink outlet, a flow channel layer inlet, and a flow channel layer outlet disposed in the cartridge body, the slots are located on both sides of the cartridge body, the installation holes are disposed on the slots, the ink inlet and the ink outlet are disposed on an upper end of the cartridge body, the flow channel layer inlet is disposed on a lower end of the cartridge body and communicates with the flow channel inlet, and the flow channel layer outlet is disposed on the lower end of the cartridge body and communicates with the flow channel outlet.

5. The arrayed electrohydrodynamic printhead without extraction electrodes according to claim 2 , wherein the ink cartridge comprises a cartridge body and installation holes, slots, an ink inlet, an ink outlet, a flow channel layer inlet, and a flow channel layer outlet disposed in the cartridge body, the slots are located on both sides of the cartridge body, the installation holes are disposed on the slots, the ink inlet and the ink outlet are disposed on an upper end of the cartridge body, the flow channel layer inlet is disposed on a lower end of the cartridge body and communicates with the flow channel inlet, and the flow channel layer outlet is disposed on the lower end of the cartridge body and communicates with the flow channel outlet.

6. The arrayed electrohydrodynamic printhead without extraction electrodes according to claim 1 , wherein each of the nozzles is made of an insulating material, and one end of each of the nozzles is a hollow boss structure, and the hollow boss structures correspond to through holes of the microfluidic channels one-to-one.

7. The arrayed electrohydrodynamic printhead without extraction electrodes according to claim 1 , wherein the nozzle plate further comprises a hydrophobic layer, and the hydrophobic layer is disposed on an outer surface of the nozzles and the nozzle electrodes.

8. The arrayed electrohydrodynamic printhead without extraction electrodes according to claim 1 , wherein the ink cartridge is made of an insulating material or a conductive material plus a layer of insulating material.

Assignees

• Univ Huazhong Science Tech

Inventors

• Duan Yongqing
• Yang Weili
• Li Huayang
• Gao Jixin
• Yin Zhouping

Classifications

• B41J2/06 Primary

  by electric or magnetic field · CPC title

• B41J2/04576

  controlling heads of electrostatic type · CPC title

• B41J2002/062

  by using a divided counter electrode opposite to ejection openings of an electrostatic printhead, e.g. for controlling the flying direction of ejected toner particles by providing the divided parts of the counter electrode with different potentials · CPC title

• B41J2202/18

  Electrical connection established using vias · CPC title

• B41J2/14 Primary

  Structure thereof {only for on-demand ink jet heads} · CPC title