Printhead with fluid flow control

• US 8,393,714 B2
• Filed: 11/14/2011
• Issued: 03/12/2013
• Est. Priority Date: 07/15/1997
• Status: Expired due to Fees

• Current Assignee: Memjet Technology Ltd. (Memjet Limited)
• Original Assignee: Zamtec Limited (Memjet Limited)
• Inventors: Silverbrook, Kia
• Primary Examiner(s): JACKSON, JUANITA DIONNE
• Application Number:
  US13/296,211
• Publication Number:
  US 20120056952A1
• Time in Patent Office: 484 Days
• Field of Search: 347/20, 347/44, 347/47, 347/54, 347/56, 347 61- 65, 347/67
• US Class Current: 347/54
• CPC Class Codes: B41J 2/14314 Structure of ink jet print heads with electrostatically actuated membrane
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• 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 2/17513 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 2002/14435 : Moving nozzle made of thermal bend detached actuator
• CPC Class Codes: B41J 2202/21 : Line printing
• 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: 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 is provided having a plurality of ejection nozzles defined on a substrate, each nozzle having a fluid chamber and ejection port, a plurality of supply channels defined through the substrate, a plurality of feed channels connecting the supply channels to the chambers thereby supplying fluid from the supply channels to the chambers, and a plurality of ejection actuators positioned in respective ones of the chambers for causing ejection of the supplied fluid from the ejection ports. Each feed channel is long and narrow relative to the dimensions of the ejection nozzles such that the fluid in the chamber is restricted from flowing into the feed channels during fluid ejection by viscous drag generated in the feed channels.

Claims

1. A printhead comprising:

a plurality of ejection nozzles defined on a substrate, each nozzle having a fluid chamber and ejection port;

a plurality of supply channels defined through the substrate;

a plurality of feed channels connecting the supply channels to the chambers thereby supplying fluid from the supply channels to the chambers; and

a plurality of ejection actuators positioned in respective ones of the chambers for causing ejection of the supplied fluid from the ejection ports,

wherein each feed channel is long and narrow relative to the dimensions of the ejection nozzles such that the fluid in the chamber is restricted from flowing into the feed channels during fluid ejection by viscous drag generated in the feed channels.

2. A printhead according to claim 1 wherein the actuators has at least one resistive heater element.

3. A printhead according to claim 1 wherein the supply channels define a larger flow path than the feed channels.

4. A printhead according to claim 1 wherein the ejection nozzles are all formed in a common layer of material which partially defines the chambers, each chamber being partially defined by at least one side wall extending from the common layer of material towards the substrate.

5. A printhead according to claim 4 wherein the at least one side wall is integral with the common layer of material.