Printhead chip that incorporates micro-mechanical lever mechanisms

• US 7,131,715 B2
• Filed: 01/03/2005
• Issued: 11/07/2006
• 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): Nguyen, Thinh
• Application Number:
  US11/026,118
• Publication Number:
  US 20050110826A1
• Time in Patent Office: 673 Days
• Field of Search: None
• US Class Current: 347/20
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/1601 Production of bubble jet print heads B41J2/1606, B41J2/162 take precedence
• 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 2202/21 : Line printing
• CPC Class Codes: B41J 3/445 : Printers integrated in other types of apparatus, e.g. printers integrated in cameras
• CPC Class Codes: B82Y 30/00 : Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G06F 21/79 : in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06F 21/86 : Secure or tamper-resistant housings
• CPC Class Codes: G06F 2221/2129 : Authenticate client device independently of the user
• 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 19/06037 : multi-dimensional coding
• CPC Class Codes: G06K 7/14 : using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• 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 printhead chip includes a substrate that incorporates drive circuitry and defines a plurality of ink inlet channels. Nozzle chamber structures are positioned on the substrate and define nozzle chambers in fluid communication with respective ink inlet channels and ink ejection ports in fluid communication with respective nozzle chambers. Elongate micro-electromechanical actuators are fast with the substrate at first ends to be connected to the drive circuitry so that second ends are displaceable reciprocally with respect to the substrate on receipt of electrical signals from the drive circuitry. Ink ejection members are positioned in respective nozzle chambers and are displaceable with respect to the substrate to eject ink from associated ink ejection ports. Micro-mechanical lever mechanisms are interposed between respective actuators and ink displacement members so that displacement of the actuators is transmitted to the ink displacement members.

Claims

1. A printhead integrated circuit which comprises a substrate that incorporates drive circuitry and defines a plurality of ink inlet channels;

nozzle chamber structures positioned on the substrate and defining nozzle chambers in fluid communication with respective ink inlet channels and ink ejection ports in fluid communication with respective nozzle chambers;

elongate micro-electromechanical actuators fast with the substrate at first ends to be connected to the drive circuitry so that second ends are displaceable reciprocally with respect to the substrate on receipt of electrical signals from the drive circuitry;

ink ejection members positioned in respective nozzle chambers and displaceable with respect to the substrate to eject ink from associated ink ejection ports; and

micro-mechanical lever mechanisms interposed between respective actuators and ink ejection members so that displacement of the actuators is transmitted to the ink ejection members.

2. A printhead integrated circuit as claimed in claim 1, in which the nozzle chamber structures include nozzle chamber walls that bound the respective nozzle chambers and include roof walls that define the ink ejection ports.

3. A printhead integrated circuit as claimed in claim 2, in which the lever mechanisms define one of the walls of each nozzle chamber structure and the lever mechanisms and the roof walls define fluidic sealing structures to inhibit the egress of ink from the nozzle chambers during displacement of the lever mechanisms with respect to the roof walls.

4. A printhead integrated circuit as claimed in claim 3, in which the lever mechanisms are first class lever mechanisms and have effort formations connected to respective second ends of the actuators, load formations connected to respective ink ejection members and fulcrum formations interposed between respective load formations and effort formations.

5. A printhead integrated circuit as claimed in claim 4, in which the roof walls and the load formations define gaps to permit movement of the load formations with respect to the roof walls, the load formations and the roof walls being configured to define the fluidic sealing structures in the form of meniscus anchor points to permit ink in the nozzle chambers to form menisci that span the respective gaps.

6. A printhead integrated circuit as claimed in claim 1, in which the micro-electromechanical actuators are of a conductive material capable of thermal expansion and each have an active portion that defines an electrical heating circuit connected to the drive circuitry at the first end and a passive portion electrically isolated from the drive circuitry at the first end and positioned with respect to the active portion so that heating and expansion of the active portion results in deflection of the actuator and movement of the second end relative to the substrate in one direction and cooling and contraction of the active portion results in movement of the actuator in an opposite direction.

7. A printhead integrated circuit as claimed in claim 6, in which the passive portions are interposed between the substrate and respective active portions so that expansion of the active portions generates deflection of the actuators towards the substrate and subsequent contraction of the active portions generates deflection of the actuators away from the substrate.

8. A printhead integrated circuit as claimed in claim 6, in which the actuators are of a resiliently flexible material to enhance deflection upon contraction of the active portions.