Inkjet printhead and printhead nozzle arrangement

• US 7,914,115 B2
• Filed: 06/04/2009
• Issued: 03/29/2011
• Est. Priority Date: 10/16/1998
• Status: Expired due to Fees

• Current Assignee: Zamtec Limited (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Luu; Matthew
• Assistant Examiner(s): LEGESSE, HENOK D
• Application Number:
  US12/478,703
• Publication Number:
  US 20090244193A1
• Time in Patent Office: 663 Days
• Field of Search: 347 40- 43, 347/49, 347 62- 65, 347/20
• US Class Current: 347/40
• CPC Class Codes: B05D 2201/00 Polymeric substrate or laminate
• CPC Class Codes: B05D 3/08 by flames
• CPC Class Codes: B41J 2/04528 aiming at warming up the head
• CPC Class Codes: B41J 2/04541 Specific driving circuit
• CPC Class Codes: B41J 2/04543 Block driving
• CPC Class Codes: B41J 2/04553 detecting ambient temperature
• CPC Class Codes: B41J 2/04563 detecting head temperature; Ink temperature
• CPC Class Codes: B41J 2/04571 detecting viscosity
• CPC Class Codes: B41J 2/04585 controlling heads based on thermal bent actuators
• CPC Class Codes: B41J 2/04588 using a specific waveform
• CPC Class Codes: B41J 2/04591 Width of the driving signal being adjusted
• CPC Class Codes: B41J 2/04596 Non-ejecting pulses
• 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 2/1623 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 2/1639 : sacrificial molding
• CPC Class Codes: B41J 2/1642 : thin film formation by CVD [chemical vapor deposition]
• 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 2002/14419 : Manifold
• CPC Class Codes: B41J 2002/14491 : Electrical connection
• CPC Class Codes: Y10T 29/49345 : Catalytic device making

Abstract

A printhead for an inkjet printer comprises a wafer assembly defining a plurality of spaced apart groups of ink supply channels and a plurality of groups of ink ejection nozzle arrangements. Each ink ejection nozzle arrangement comprises a nozzle chamber structure mounted to the wafer assembly. Each ink ejection nozzle arrangement further comprises an anchor extending from the wafer assembly in a location external to the nozzle chamber; and an elongate thermal actuator mechanism extending from the anchor and into the nozzle chamber. The thermal actuator mechanism comprises an elongate arm which terminates in a free end within the nozzle chamber, and a pair of layers of conductive material located on either side of the elongate arm. One of the layers is connected to a current supply for causing a differential thermal expansion in the elongate thermal actuator mechanism. A pit is defined adjacent each nozzle chamber structure for catching ink. The ink ejection nozzle arrangements of each group are arranged in a pair of rows, with the elongate thermal actuator mechanism of ink ejection nozzle arrangements of a first row extending away from those of ink ejection nozzle arrangements of a second row.

Claims

1. A printhead for an inkjet printer, the printhead comprising:

a wafer assembly defining a plurality of spaced apart groups of ink supply channels and a plurality of groups of ink ejection nozzle arrangements in fluid communication with respective ink supply channel groups, each ink ejection nozzle arrangement comprising;

a nozzle chamber structure mounted to the wafer assembly, and defining a nozzle chamber for receiving ink from an ink supply channel and an ink ejection port through which ink in the nozzle chamber is ejected;

an anchor extending from the wafer assembly in a location external to the nozzle chamber; and

an elongate thermal actuator mechanism extending from the anchor and into the nozzle chamber, the thermal actuator mechanism comprising an elongate arm which terminates in a free end within the nozzle chamber and a pair of layers of conductive material located on either side of the elongate arm, one of the layers being connected to a current supply for causing a differential thermal expansion in the elongate thermal actuator mechanism so that the free end of the arm is moved to eject ink in the nozzle chamber through the ink ejection port;

wherein

a pit is defined adjacent each nozzle chamber structure for catching ink and thereby impeding spilt ink from spreading across the printhead, and

the ink ejection nozzle arrangements of each group are arranged in a pair of rows, with the elongate thermal actuator mechanism of ink ejection nozzle arrangements of a first row extending away from the elongate thermal actuator mechanism of ink ejection nozzle arrangements of a second row.

2. A printhead as claimed in claim 1, wherein the elongate thermal actuator mechanisms extend outwardly on either side of the nozzle chamber structures, and the nozzle chamber structures are centrally located.

3. A printhead as claimed in claim 1, wherein each row comprises a plurality of linearly arranged sets of nozzle arrangements with adjacent sets being staggered relative to each other along the row.

4. A printhead as claimed in claim 1, wherein the layers of conductive material are located proximal to the anchor.

5. A printhead as claimed in claim 3, wherein the sets form a plurality of ascending or descending steps.

6. A printhead as claimed in claim 4, wherein the layers of conductive material abut the anchor.