Micro-electromechanical ink ejection device with an elongate actuator

• US 7,287,834 B2
• Filed: 09/14/2006
• Issued: 10/30/2007
• 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:
  US11/520,569
• Publication Number:
  US 20070008373A1
• Time in Patent Office: 411 Days
• Field of Search: 347/54, 347/65
• US Class Current: 347/54
• CPC Class Codes: B41J 2/04 generating single droplets or particles on demand
• 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 2202/21 : Line printing
• 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 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 ink ejection device for a printer includes a wafer substrate defining an ink inlet channel and incorporating drive circuitry. A nozzle chamber structure is positioned on the wafer substrate and includes a wall that defines a slot extending away from the substrate and a roof that defines a part-circumferential opening into the slot, the nozzle chamber structure defining a nozzle chamber in fluid communication with the ink inlet channel and an ink ejection port through which ink in the nozzle chamber can be ejected. An ink ejection paddle is positioned in the nozzle chamber and is displaceable towards and away from the ink ejection port to eject ink from the ink ejection port. A support extends from the wafer substrate outside the nozzle chamber. An elongate actuator extends from the support and is connected to the drive circuitry to be displaceable on receipt of a signal from the drive circuitry. The actuator is connected to the paddle and is shaped to correspond with the slot and the part circumferential opening.

Claims

1. A micro-electromechanical ink ejection device for a printer, the device comprising:

a wafer substrate defining an ink inlet channel and incorporating drive circuitry;

a nozzle chamber structure positioned on the wafer substrate and including a wall that defines a slot extending away from the substrate and a roof that defines a part-circumferential opening into the slot, the nozzle chamber structure defining a nozzle chamber in fluid communication with the ink inlet channel and an ink ejection port through which ink in the nozzle chamber can be ejected;

an ink ejection paddle positioned in the nozzle chamber and displaceable towards and away from the ink ejection port to eject ink from the ink ejection port;

a support extending from the wafer substrate outside the nozzle chamber; and

an elongate actuator extending between the support and the paddle, a heater disposed at the support end of the actuator being connected to the drive circuitry to cause displacement of the paddle end of the actuator on receipt of a signal from the drive circuitry, the actuator being shaped to correspond with the slot and the part circumferential opening.

2. An ink ejection device as claimed in claim 1, wherein the ink chamber and ink inlet channel have a substantially equivalent cross sectional area.

3. An ink ejection device as claimed in claim 1, in which the heater is positioned so that the actuator undergoes thermal differential expansion and contraction to move the paddle.

4. An ink ejection device as claimed in claim 3, wherein the heater comprises an anchor which is contained within the support and the wafer substrate to be connected to the drive circuitry, and a heating element which extends from the support.

5. An ink ejection device as claimed in claim 4, wherein the actuator includes a body portion of a structural material and the heating element is located between the body portion and the wafer substrate.

6. An ink ejection device as claimed in claim 5, wherein the heating element is formed from copper nickel alloy.

7. An ink ejection device as claimed in claim 1, wherein the paddle defines a recess which faces toward the ink ejection port.