Ink jet with high young's modulus actuator

• US 6,460,971 B2
• Filed: 03/02/2001
• Issued: 10/08/2002
• Est. Priority Date: 07/15/1997
• Status: Expired due to Fees

• Current Assignee: Zamtec Limited (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Gordon, Raquel Yvette
• Application Number:
  US09/798,757
• Publication Number:
  US 20010012035A1
• Time in Patent Office: 585 Days
• Field of Search: 347/55, 347/68, 347/69, 347/70, 347/71, 347/72, 347/50, 347/40, 347/20, 347/44, 347/47, 347/48, 399/261, 361/700, 310/328-330, 298/901, 216/4, 216/48, 216/27
• 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 2/1628 dry 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 2/1639 sacrificial molding
• CPC Class Codes: B41J 2/1642 thin film formation by CVD [chemical vapor deposition]
• 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 2/17596 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: 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 jet nozzle assembly includes a nozzle chamber having an inlet in fluid communication with an ink reservoir and a nozzle through which ink from the chamber can be ejected. The chamber includes a fixed portion and a movable portion configured for relative movement in an ejection phase and alternate relative movement in a refill phase. A thermal actuator connects with the movable portion and comprises materials having a high Young'"'"'s modulus which produce a bending motion upon heating to effect periodically said relative movement. The inlet is positioned and dimensioned relative to the nozzle such that ink is ejected preferentially from the chamber through the nozzle in droplet form during the ejection phase, and ink is alternately drawn preferentially into the chamber from the reservoir through the inlet during the refill phase.

Claims

1. An ink jet nozzle assembly including a nozzle chamber having a nozzle through which ink from the chamber can be ejected, the chamber including a fixed portion and a movable portion configured for relative movement in an ejection phase and alternate relative movement in a refill phase, and an actuator connected with the movable portion and comprising materials having a Young'"'"'s modulus greater than about 200 Gpa.

2. An ink jet nozzle assembly including:

a nozzle chamber having an inlet in fluid communication with an ink reservoir and a nozzle through which ink from the chamber can be ejected;

the chamber including a fixed portion and a movable portion configured for relative movement in an ejection phase and alternate relative movement in a refill phase;

a thermal actuator connected with the movable portion and comprising materials having a high Young'"'"'s modulus which produce a bending motion upon heating to effect periodically said relative movement; and

the inlet being positioned and dimensioned relative to the nozzle such that ink is ejected preferentially from the chamber through the nozzle in droplet form during the ejection phase, and ink is alternately drawn preferentially into the chamber from the reservoir through the inlet during the refill phase;

wherein the movable portion includes the nozzle and the fixed portion is mounted on a substrate.

3. An assembly according to claim 2 wherein the fixed portion includes the nozzle mounted on a substrate and the movable portion includes an ejection paddle.

4. An assembly according to claim 3 wherein said thermal actuator is pivoted so as to increase a degree of travel of said ejection paddle upon actuation of said thermal actuator.

5. An assembly according to claim 3 wherein said actuator is of a horse-shoe shape pivoted substantially about a midpoint thereof.

6. An assembly according to claim 5 wherein said midpoint is constructed on a wall of said chamber.

7. An assembly according to claim 6 wherein said wall comprises a thinned membrane.

8. An assembly according to claim 2 wherein said thermal actuator operates in an ambient atmosphere.

9. An assembly according to claim 2 wherein said nozzle chamber is constructed on a silicon wafer and said ink is supplied through said silicon wafer.

10. An assembly according to claim 2 wherein said thermal actuator is constructed from a thin conductive section and a substantially thicker non-conductive section.

11. An assembly according to claim 10 wherein said thin conductive section comprises substantially titanium diboride.

12. An assembly according to claim 10 wherein said thicker portion comprises substantially glass.

13. An assembly according to claim 2 wherein said nozzle chamber has walls that include a number of small sacrificial etchant holes to facilitate construction of said assembly, said holes being of a diameter sufficiently small so as to prevent an ejection of ink therethrough.

14. An assembly according to claim 2, manufactured using micro-electro-mechanical systems (MEMS) techniques.

15. An assembly according to claim 2 wherein an effective volume of the chamber is reduced in said ejection phase and enlarged in said refill phase.