Planar swing grill electromagnetic ink jet printing mechanism

• US 6,257,704 B1
• Filed: 07/10/1998
• Issued: 07/10/2001
• 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): Barlow, John
• Assistant Examiner(s): Do, An H.
• Application Number:
  US09/113,066
• Time in Patent Office: 1,096 Days
• Field of Search: 347/20, 347/44, 347/54, 347/47, 347/85
• US Class Current: 347/54
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• CPC Class Codes: B41J 2/14314 Structure of ink jet print heads with electrostatically actuated membrane
• CPC Class Codes: B41J 2/16 Production of nozzles
• CPC Class Codes: B41J 2/1623 bonding and adhesion
• 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 2/1643 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 2/16585 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: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• 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

An ink jet print head uses a magnetic coil as part of its actuation process. An ink jet nozzle includes a shutter interconnecting the reservoir and the nozzle chamber, the shutter being operable by an electromagnet so as to control the ejection of ink. The electromagnet moves an arm interconnected to one end of the shutter, thereby opening a channel for the flow of ink, followed by maintaining a keeper current so as to maintain the channel in an open state, followed by deactivation of the electromagnet. The shutter subsequently returns to a closed position. The ink jet includes a coiled spring connected to the shutter. The spring is elastically deformed by the electromagnet and returns to an initial state upon deactivation of the shutter so as to restrict the further flow of fluid from the ink reservoir to the nozzle chamber.

Claims

1. An ink jet print head comprising:

an ink reservoir containing an ink supply under an oscillating pressure;

a nozzle chamber having an ink ejection port for ejecting ink drops onto a print media; and

a shutter device located between said reservoir and said nozzle chamber, said shutter device being operated by an electromagnet so as to control an ejection of ink from said ink ejection port.

2. An ink jet print head as claimed in claim 1 wherein said electromagnet is attached to an arm that is connected to said shutter device.

3. An ink jet print head as claimed in claim 2 wherein said electromagnet includes first and second ends and wherein each of said ends is positioned closely adjacent to said arm and said electromagnet moves said arm closer to both of said ends.

4. An ink jet print head as claimed in claim 2 wherein said arm is pivoted between said first and second ends of said electromagnet.

5. An ink jet print head as claimed in claim 1 wherein the electromagnet has a spiral shape.

6. An ink jet print head as claimed in claim 1 further comprising:

a resilient device connected to said shutter device, said resilient device being elastically deformed by said electromagnet and said resilient device operating to return to an initial state upon deactivation of said shutter device so as to restrict further flow of fluid from said ink reservoir to said nozzle chamber.

7. An ink jet print head as claimed in claim 6 wherein said resilient device comprises a coiled spring.

8. An ink jet print head as claimed in claim 1 wherein said electromagnet is formed utilizing semi-conductor fabrication techniques from a copper coil surrounding a soft metal core.

9. An ink jet print head as claimed in claim 8 wherein said copper coil is formed by a damascene process.

10. An ink jet print head as claimed in claim 1 wherein said shutter device comprises a series of moveable slats moveable over apertures in a wall of said nozzle chamber.

11. A method of ejecting ink from an ink jet print head comprising the steps of:

utilizing an electromagnetically activated shutter to control a flow of ink into a nozzle chamber such that ink is ejected from said nozzle chamber when said shutter is open;

utilizing a first high pressure cycle of an oscillating pressure ink supply to eject ink from said nozzle chamber;

utilizing a low pressure cycle of said oscillating pressure ink supply for a separation of an ink drop from the ink in said nozzle chamber; and

utilizing a second high pressure cycle of said oscillating pressure ink supply to refill said nozzle chamber with ink.