Radial back-curling thermoelastic ink jet printing mechanism

• US 6,283,581 B1
• Filed: 07/10/1998
• Issued: 09/04/2001
• Est. Priority Date: 06/09/1998
• 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:
  US09/112,807
• Time in Patent Office: 1,152 Days
• Field of Search: 347/44, 347/54, 347/84, 347/85, 347/20, 347/47
• US Class Current: 347/54
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• CPC Class Codes: B41J 2/16 Production of nozzles
• CPC Class Codes: B41J 2/1628 dry etching
• CPC Class Codes: B41J 2/1629 wet etching
• CPC Class Codes: B41J 2/1632 machining
• CPC Class Codes: B41J 2/17596 Ink pumps, ink valves
• CPC Class Codes: B41J 2202/15 Moving nozzle or nozzle plate

Abstract

A nozzle arrangement for an ink jet printhead includes a wafer substrate having a nozzle chamber defined therein. The nozzle arrangement has a nozzle chamber wall that defines an ink ejection port and a rim about the ink ejection port. A series of radially positioned actuators are attached to the nozzle rim and extend radially from the rim to form a portion of the nozzle chamber wall adjacent the rim. Each actuator is configured so that a radially outer edge of each actuator is displaceable into the chamber, upon actuation of the actuator and so that, upon such displacement, a pressure within the nozzle chamber is increased, resulting in the ejection of ink from the ejection port.

Claims

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

a wafer substrate having a nozzle chamber defined therein;

a nozzle chamber wall that defines an ink ejection port and a rim about the ink ejection port; and

a series of radially positioned actuators attached to the nozzle rim and extending radially from the rim to form a portion of the nozzle chamber wall adjacent the rim, each actuator being configured so that a radially outer edge of each actuator is displaceable into the chamber, upon actuation of the actuator and so that, upon such displacement, a pressure within the nozzle chamber is increased, resulting in the ejection of ink from the ejection port.

2. A nozzle arrangement as claimed in claim 1, wherein the actuators are configured to bend into the nozzle chamber towards a centre of the nozzle chamber.

3. A nozzle arrangement as claimed in claim 2, wherein each actuator comprises a conductive resistive heating element encased within a material having a coefficient of thermal expansion suitable for creating displacement of the actuator upon uneven heating of said material.

4. A nozzle arrangement as claimed in claim 3, wherein the conductive resistive heating element of each actuator is positioned within said material so that uneven heating of said material results, causing the displacement of each actuator into the nozzle chamber.

5. A nozzle arrangement as claimed in claim 3, wherein the resistive heating element of each actuator is serpentine to allow for substantially unhindered expansion of said material.

6. A nozzle arrangement as claimed in claim 3, in which a number of struts interconnect said rim to said wafer substrate, each strut incorporating a power rail for supplying electrical power to the conductive resistive heating element.

7. An ink jet nozzle arrangement as claimed in claim 1, in which an ink inlet channel is defined in said wafer substrate and is in fluid communication with the nozzle chamber.

8. A printhead which comprises a plurality of ink jet nozzle arrangements as claimed in claim 1.