Ink jet printhead that includes coiled actuators

• US 6,644,787 B2
• Filed: 11/12/2002
• Issued: 11/11/2003
• 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): Meier, Stephen D.
• Assistant Examiner(s): Do, An H.
• Application Number:
  US10/291,708
• Publication Number:
  US 20030063159A1
• Time in Patent Office: 364 Days
• Field of Search: 347/20, 347/40, 347/44, 347/47, 347/54, 347/55, 347/56, 347/63, 347/65, 347/68-72
• 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 2/17513 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: 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 nozzle arrangement for an ink jet printhead includes a substrate. An actuator is positioned on the substrate to facilitate the ejection of ink from a nozzle chamber of the nozzle arrangement. The actuator has a coiled working portion that is configured to uncoil at least partially to perform work, when the coiled working portion receives an electrical signal.

Claims

1. A nozzle arrangement for an ink jet printhead, the nozzle arrangement comprising:

a substrate; and

an actuator that is positioned on the substrate to facilitate the ejection of ink from a nozzle chamber of the nozzle arrangement, the actuator comprising an elongate, flexible, curved actuator arm having an inner end and an outer end, the inner end being fixed to the substrate and an actuating mechanism that is operatively arranged with respect to the actuator arm to straighten the actuator arm at least partially when activated by an electrical signal such that the outer end is displaced to an extent sufficient to perform work.

2. A nozzle arrangement as claimed in claim 1, in which the substrate includes a wafer substrate and a drive circuitry layer positioned in the wafer substrate.

3. A nozzle arrangement as claimed in claim 1, in which the actuator arm is curved to define a coil.

4. A nozzle arrangement as claimed in claim 3, in which the actuator arm is coiled through at least 360 degrees.

5. A nozzle arrangement as claimed in claim 2, in which the actuating mechanism includes a conductive heater element that is fixed to an inner side of the actuator arm and is connected to drive circuitry in the drive circuitry layer, the heater element being capable of being resistively heated when an electrical current from the drive circuitry layer is set up in the heater element, the heater element being capable of expansion when so heated, so that, when the heater element expands, the actuator arm is partially straightened so that the outer end of the actuator arm is displaced to perform work.

6. A nozzle arrangement as claimed in claim 3, in which the actuator arm is substantially of a material having a coefficient of thermal expansion which is such that, when heated, subsequent expansion of the material is sufficient to perform work, the actuating mechanism including a conductive heater element which is positioned in the actuator arm at or proximate an inner side of the actuator arm so that an inner longitudinal portion of the actuator arm is heated to a greater extent than an outer longitudinal portion of the actuator arm resulting in greater expansion of said inner longitudinal portion with a subsequent partial straightening of said actuator arm so that the outer end of the actuator arm is displaced to perform work.

7. A nozzle arrangement as claimed in claim 1, in which a paddle is mounted on the outer end of the actuator arm and is positioned in the nozzle chamber to eject ink from the nozzle chamber.

8. A nozzle arrangement as claimed in claim 1, in which the substrate defines an inlet for the nozzle chamber, so that ink can be supplied to the nozzle chamber.

9. An ink jet printhead that comprises:

a substrate; and

a plurality of nozzle arrangements positioned on the substrate, each nozzle arrangement having an actuator that is positioned on the substrate to facilitate the ejection of ink from a nozzle chamber of the nozzle arrangement, the actuator comprising an elongate, flexible, curved actuator arm having an inner end and an outer end, the inner end being fixed to the substrate and an actuating mechanism that is operatively arranged with respect to the actuator arm to straighten the actuator arm at least partially when activated by an electrical signal such that the outer end is displaced to an extent sufficient to perform work.