Differential thermal ink jet printing mechanism

• US 6,416,170 B2
• Filed: 03/02/2001
• Issued: 07/09/2002
• 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 Y.
• Application Number:
  US09/798,416
• Publication Number:
  US 20010009430A1
• Time in Patent Office: 494 Days
• Field of Search: 347/54, 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 2/1629 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 2/1639 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 receiving ink from a reservoir and a nozzle through which the ink 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 pair of spaced apart actuating arms is connected with the movable portion and undergoes differential thermal expansion upon heating to effect periodically the 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, the chamber including a movable portion configured for movement to effect ejection of ink from the chamber via said nozzle, and a pair of actuating arms attached to or formed integrally with the movable portion, the arms effecting movement of said movable portion as a result of one of said arms being periodically hotter than the other said arm in use.

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 pair of spaced apart actuating arms connected with the movable portion and undergoing differential thermal expansion 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.

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

4. 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.

5. An assembly according to claim 4 wherein the arms extend between the paddle and the substrate.

6. An assembly according to claim 4 wherein the arms are located substantially outside the chamber.

7. An assembly according to claim 6 wherein the fixed portion includes a slot a sidewall of the chamber through which the arms are connected to the paddle.

8. An assembly according to claim 2 wherein the arms are located substantially within the chamber.

9. An assembly according to claim 2 wherein the arms are of substantially the same cross-sectional profile relative to one another.

10. An assembly according to claim 2 wherein the arms are of differing cross-sectional profile relative to one another.

11. An assembly according to claim 2 wherein the arms are heated simultaneously.

12. An assembly according to claim 2 wherein one arm is heated to a higher temperature than the other arm.

13. An assembly according to claim 2 wherein the arms are of substantially the same material composition relative to one another.

14. An assembly according to claim 2 wherein the arms are of substantially different material composition relative to one another.

15. An assembly according to claim 2 wherein the arms are substantially parallel to one another.

16. An assembly according to claim 2 wherein the arms are substantially non-parallel to one another.

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

18. 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.