Stacked electrostatic ink jet printing mechanism

• US 6,231,163 B1
• Filed: 07/10/1998
• Issued: 05/15/2001
• Est. Priority Date: 07/15/1997
• Status: Expired due to Fees

• Current Assignee: Zamtec Limited (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): Do, An H.
• Application Number:
  US09/112,803
• Time in Patent Office: 1,040 Days
• Field of Search: 347/44, 347/54, 347/20, 347/47, 347/68, 347/71
• US Class Current: 347/54
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• CPC Class Codes: B41J 2/14314 Structure of ink jet print heads with electrostatically actuated membrane
• CPC Class Codes: B41J 2/16 Production of nozzles
• CPC Class Codes: B41J 2/1623 bonding and adhesion
• CPC Class Codes: B41J 2/1628 dry etching
• CPC Class Codes: B41J 2/1629 wet etching
• CPC Class Codes: B41J 2/1631 photolithography
• CPC Class Codes: B41J 2/1632 machining
• CPC Class Codes: B41J 2/1639 sacrificial molding
• CPC Class Codes: B41J 2/1642 thin film formation by CVD [chemical vapor deposition]
• CPC Class Codes: B41J 2/1643 thin film formation by plating
• CPC Class Codes: B41J 2/1645 thin film formation by spincoating
• CPC Class Codes: B41J 2/1646 thin film formation by sputtering
• CPC Class Codes: B41J 2/16585 for paper-width or non-reciprocating print heads
• CPC Class Codes: B41J 2/17596 Ink pumps, ink valves
• CPC Class Codes: B41J 2002/041 Electromagnetic transducer
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G06K 1/121 by printing code marks applying code marks to labels B65C9/46; marking or coding completed packages B65B61/26
• CPC Class Codes: G06K 19/06037 multi-dimensional coding
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G06K 7/1417 : 2D bar codes
• CPC Class Codes: G11C 11/56 : using storage elements with more than two stable states represented by steps, e.g. of voltage, current, phase, frequency
• CPC Class Codes: H04N 23/00 : Cameras or camera modules comprising electronic image sensors; Control thereof
• CPC Class Codes: H04N 5/2628 : Alteration of picture size, shape, position or orientation, e.g. zooming, rotation, rolling, perspective, translation

Abstract

This patent describes an ink jet printer utilizing a stacked capacitor arrangement to actuate the ejection of ink from a nozzle chamber. The stacked capacitor includes a series of conductive parallel plates interleaved with a resiliently compressible material. A potential difference is produced across the plates so as to attract adjacent plates to one another thereby causing the compressible material to resiliently yield. The compression results in ink being drawn into the nozzle chamber by means of surface tension effects around the ink ejection port. The potential difference is then reduced such that the compressible material returns to its quiescent state, thereby resulting in the ejection of ink. The compressible material preferably includes a material having a high dielectric constant and constructed utilizing semiconductor fabrication techniques by laying down one planar layer at a time constructed utilizing chemical vapor deposition techniques so as to form an initial sandwiched preform and subsequently selectively etching the preform so as to provide for an electrical interconnect to the conductive parallel plates.

Claims

1. An ink jet nozzle apparatus comprising:

a nozzle chamber having an ink ejection port in one wall of said chamber;

an ink supply source interconnected to said nozzle chamber;

an electrostatic actuator to eject ink from said nozzle chamber via said ink ejection port, said electrostatic actuator comprising a series of conductive parallel plates interleaved with resiliently compressible material layers laid down as thin film between the parallel plates;

means for

producing a potential difference across said plates so as to attract adjacent plates to one another thereby causing said compressible material layers to resiliently yield; and

means for reducing said potential difference such that said compressible material layers return to their quiescent state, thereby resulting in the ejection of ink from said ejection port.

2. An apparatus as claimed in claim 1 wherein said compressible material is sufficiently yielding to result in ink being drawn into said nozzle chamber by means of surface tension effects around said ink ejection port.

3. An ink jet nozzle as claimed in claim 1 wherein said compressible material comprises a material having a high dielectric constant.

4. An ink jet nozzle as claimed in claim 1 wherein said electrostatic actuator comprises planar sandwiched layers that are selectively etched to provide an electrical interconnect to the conductive parallel plates.

5. An ink jet nozzle as claimed in claim 1 wherein groups of said series of said conductive parallel plates are constructed from different materials selectively etched and divided into two groups of different polarities.

6. An ink jet nozzle as claimed in claim 5 wherein plates from each of said group are interconnected to a common conductive portion for the provision of a charge to said conductive plates.

7. An ink jet nozzle as claimed in claim 1 wherein said plates are constructed utilizing chemical vapor deposition techniques.

8. An ink jet nozzle as claimed in claim 1 wherein an outer surface of said nozzle chamber includes a plurality of etchant holes.

9. An ink jet nozzle comprising:

a nozzle chamber having an ink ejection port in one wall of said chamber;

an ink supply source interconnected to said nozzle chamber;

an electrostatic actuator to eject ink from said nozzle chamber via said ink ejection port, said electrostatic actuator comprising a series of conductive parallel plates interleaved with resiliently compressible material layers laid down as thin film between the parallel plates; and

control means for producing a potential difference across said plates so that said material layers are resiliently compressed such that, upon deactivation, said electrostatic actuator causes ink to be ejected via said ink ejection port.