Ink ejection mechanism with thermal actuator coil

• US 8,029,101 B2
• Filed: 01/12/2011
• Issued: 10/04/2011
• 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:
  US13/005,521
• Publication Number:
  US 20110109700A1
• Time in Patent Office: 265 Days
• Field of Search: 347/54, 347/56, 347/65
• US Class Current: 347/54
• 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 2202/21 : Line printing
• CPC Class Codes: B82Y 30/00 : Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G06F 21/79 : in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06F 21/86 : Secure or tamper-resistant housings
• CPC Class Codes: G06F 2221/2129 : Authenticate client device independently of the user
• 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 19/073 : Special arrangements for circuits, e.g. for protecting identification code in memory protection against unauthorised use of computer memory G06F12/14
• 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

A micro-electromechanical ejection mechanism is disclosed for ejecting an ink droplet. The mechanism has a wafer substrate and an ink chamber formed on the wafer substrate. The ink chamber has an ink ejection nozzle formed in a roof thereof and an ink inlet port formed in a floor thereof. A paddle device is arranged inside the ink chamber between the inlet port and the ejection nozzle A bi-layer thermal actuator coil is also included with a first end thereof fast with the substrate and a second end connected to the paddle device. Heating of the thermal actuator coil displaces the paddle device, causing ejection of an ink droplet through the ink ejection nozzle.

Claims

1. A micro-electromechanical ejection mechanism comprising:

a wafer substrate;

an ink chamber formed on said wafer substrate, the ink chamber having an ink ejection nozzle formed in a roof thereof and an ink inlet port formed in a floor thereof;

a paddle device arranged inside the ink chamber between the inlet port and the ejection nozzle; and

a bi-layer thermal actuator coil with a first end fast with the substrate and a second end connected to the paddle device, wherein heating of the thermal actuator coil displaces the paddle device causing ejection of an ink droplet through the ink ejection nozzle.

2. The micro-electromechanical ejection mechanism as claimed in claim 1, wherein the bi-layer thermal actuator coil includes a first layer manufactured from a non-conductive material and a second layer manufactured from a conductive material, wherein applying current to the second layer causes the thermal actuator coil to expand.

3. The micro-electromechanical ejection mechanism as claimed in claim 2, wherein the first layer is manufactured from glass and the second layer is manufactured from titanium diboride.

4. The micro-electromechanical ejection mechanism as claimed in claim 1, wherein the bi-layer thermal actuator coil is outside the ink chamber.

5. The micro-electromechanical ejection mechanism as claimed in claim 4, wherein the bi-layer thermal actuator coil is connected to the paddle device by a strut extending through an aperture in a side wall of the ink chamber.

6. The micro-electromechanical ejection mechanism as claimed in claim 5, wherein the strut and the aperture are treated to be hydrophobic.

7. The micro-electromechanical ejection mechanism as claimed in claim 1, wherein movement of the paddle device is perpendicular to movement of the ejected ink droplet.

8. The micro-electromechanical ejection mechanism as claimed in claim 1, wherein a rim is formed around a perimeter of the ink nozzle, the rim being configured to exploit surface tension characteristics of ink in the chamber to prevent ink from flowing out of the chamber.