Printhead having inkjet actuators with contractible chambers

• US 7,461,924 B2
• Filed: 07/03/2006
• Issued: 12/09/2008
• Est. Priority Date: 07/15/1997
• Status: Expired due to Fees

• Current Assignee: Memjet Technology Ltd. (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Do; An H
• Application Number:
  US11/478,585
• Publication Number:
  US 20060244784A1
• Time in Patent Office: 890 Days
• Field of Search: 347/54, 347/56, 347/65
• US Class Current: 347/56
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/1623 bonding and adhesion
• CPC Class Codes: B41J 2/1626 etching
• 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 2/1635 dividing the wafer into individual chips
• CPC Class Codes: B41J 2/1637 molding
• 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 2/1648 Production of print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/16585 for paper-width or non-reciprocating print heads
• CPC Class Codes: B41J 2/17503 Ink cartridges
• CPC Class Codes: B41J 2/17513 Inner structure
• CPC Class Codes: B41J 2/17596 Ink pumps, ink valves
• CPC Class Codes: B41J 2002/041 : Electromagnetic transducer
• CPC Class Codes: B41J 2002/14346 : Ejection by pressure produced by thermal deformation of ink chamber, e.g. buckling
• CPC Class Codes: B41J 2002/14435 : Moving nozzle made of thermal bend detached actuator
• CPC Class Codes: B41J 2002/14443 : Nozzle guard
• CPC Class Codes: B41J 2202/21 : Line printing
• 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 1/2112 : using still video cameras
• CPC Class Codes: H04N 1/2154 : the still video camera incorporating a hardcopy reproducing device, e.g. a printer
• CPC Class Codes: H04N 2101/00 : Still video cameras
• 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

An ink printhead is provided having a plurality of nozzle assemblies. Each nozzle assembly has a nozzle and an actuator for ejecting ink through the nozzle. Each actuator has a resiliently contractible chamber.

Claims

1. An ink printhead comprising a plurality of nozzle assemblies, each nozzle assembly comprising:

a nozzle and an actuator for ejecting ink through said nozzles, wherein,

the actuator comprises a resiliently contractible chamber having four slidable walls each slidable by thermal actuation, each slidable wall being a side wall of the chamber.

2. An inkjet printhead according to claim 1, wherein each nozzle assembly further comprises an ink inlet for communicating ink between the chamber and an ink reservoir.

3. An inkjet printhead according to claim 2 wherein each ink inlet is defined in an inlet wall of the respective chamber and the nozzle is defined in a nozzle wall of the respective chamber which is spaced from the inlet wall and connected thereto by the at least one slidable wall.

4. An inkjet printhead according to claim 1 wherein the four side walls are arcuate vanes arranged around a central axis, and the actuator further comprises four expanding, flexible arms each connected to a respective vane, such that simultaneous actuation of the arms pushes the arcuate vanes to slidingly engage each other to contract the chamber.

5. An inkjet printhead according to claim 4 wherein said flexible expanding arms comprise a conductive heater material encased within an expansion material having a high coefficient of thermal expansion.

6. An inkjet printhead according to claim 5 wherein said conductive heater material is constructed so as to form a concertina upon expansion of said expansion material.

7. An inkjet printhead according to claim 5 wherein said heater material is of a serpentine form and forms a concertina upon heating so as to allow substantially unhindered expansion of said expansion material during heating.

8. An inkjet printhead according to claim 5 wherein said vanes are arranged annularly around said nozzle.

9. An inkjet printhead according to claim 5 wherein said vanes operate as an iris around said nozzle.

10. An inkjet printhead according to claim 5 wherein said expansion material substantially comprises polytetrafluoroethylene.

11. An inkjet printhead according to claim 5 wherein said conductive heater material substantially comprises copper.