MEMS device with movement amplifying actuator

• US 7,201,471 B2
• Filed: 06/22/2006
• Issued: 04/10/2007
• 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): JACKSON, JUANITA DIONNE
• Application Number:
  US11/472,294
• Publication Number:
  US 20060232631A1
• Time in Patent Office: 292 Days
• Field of Search: 347/20, 347/44, 347/47, 347/54, 347/56, 347 61- 63, 347/65, 347/67, 60527-529
• US Class Current: 347/54
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• CPC Class Codes: B41J 2/14427 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 2202/21 : Line printing
• 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 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

A micro-electromechanical liquid ejection device includes a substrate that defines a liquid inlet channel. Drive circuitry is positioned on the substrate. A nozzle chamber structure is positioned on the substrate and defines a nozzle chamber in fluid communication with the liquid inlet channel and a liquid ejection port in fluid communication with the nozzle chamber. A liquid ejecting mechanism is operatively arranged with respect to the nozzle chamber such that movement of the liquid ejecting mechanism results in the ejection of liquid from the liquid ejection port. An actuator is fast with the substrate and is connected to the drive circuitry to be displaced relative to the substrate on receipt of an electrical signal from the drive circuitry. The actuator is connected to the liquid ejecting mechanism to cause said movement of the liquid ejecting mechanism. The liquid ejecting mechanism has a liquid ejecting member that acts on liquid in the nozzle chamber. The actuator and the liquid ejecting mechanism are configured so that an extent of displacement of the actuator is amplified in movement of the liquid ejecting member.

Claims

1. A micro-electromechanical (MEMS) device for ejecting a drop of liquid, the MEMS device comprising:

a supporting substrate;

a chamber formed on the substrate for holding a quantity of the liquid;

an actuator attached to the substrate for movement relative to the substrate;

a liquid ejecting mechanism attached to the actuator for movement within the chamber;

drive circuitry on the substrate for generating drive signals to drive the actuator; and

,

an ejection port in fluid communication with the chamber such that movement of the liquid ejecting mechanism in response to the actuator receiving a drive signal causes a drop of the liquid ejecting through the ejection port;

wherein,

actuation of the actuator causes greater movement of the liquid ejecting mechanism relative to the substrate than the actuators movement relative to the substrate.

2. A MEMS device according to claim 1 wherein the actuator includes a force transmitting portion that is substantially linearly displaceable upon receipt of the signal from the drive circuitry and the liquid ejecting mechanism includes a micro-mechanical translating mechanism interposed between the force transmitting portion and the liquid ejecting member such that displacement of the force transmitting portion results in said movement of the liquid ejecting member.

3. A MEMS device according to claim 2 wherein the actuator includes an anchor arrangement that is fast with the substrate and extends from the substrate, the force transmitting portion being a thermal expansion member extending from the substrate to be spaced from the substrate and defining a heating circuit electrically connected to the drive circuitry layer to receive an electrical signal from the drive circuitry layer so that the expansion member expands and subsequently contracts.

4. A MEMS device according to claim 3 wherein the force transmitting portion is a lever mechanism with the liquid ejecting mechanism providing a resistance and the expansion member providing an effort.

5. A MEMS devices according to claim 4 wherein the lever mechanism includes a pivot member pivotally mounted in one of the walls of the chamber to define a fulcrum along a pivot line and interposed between the expansion member and the liquid ejection mechanism at expansion and subsequent contraction of the expansion member results in pivotal movement of the liquid ejection mechanism towards and away from the ejection port.

6. A MEMS device according to claim 1 wherein the chamber includes nozzle chamber walls and the liquid ejection port is defined in a roof that spans the walls.