Inkjet printhead with pairs of ink spread restriction pits

• US 7,524,029 B2
• Filed: 04/04/2007
• Issued: 04/28/2009
• Est. Priority Date: 10/16/1998
• 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:
  US11/730,784
• Publication Number:
  US 20070188554A1
• Time in Patent Office: 755 Days
• Field of Search: 347/20, 347/40, 347/42, 347/44, 347/47, 347/54, 347/56, 347 61- 65, 347/67, 60527-529
• US Class Current: 347/54
• CPC Class Codes: B41J 2/04518 reducing costs
• CPC Class Codes: B41J 2/04541 Specific driving circuit
• CPC Class Codes: B41J 2/04543 Block driving
• 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 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/1623 bonding and adhesion
• CPC Class Codes: B41J 2/1628 dry 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 2/1646 thin film formation by sputtering
• CPC Class Codes: B41J 2/1648 Production of print heads with thermal bend detached actuators

Abstract

A printhead is provided for an inkjet printer. The printhead includes a wafer assembly defining a plurality of spaced apart groups of ink supply channels. A plurality of groups of ink ejection nozzle arrangements is provided in fluid communication with respective ink supply channel groups. Each group of nozzle arrangements includes a pair of rows of nozzle arrangements. A plurality of pairs of ink spread restriction pits is defined within respective groups of nozzle arrangements. The pairs of pits extend between the rows.

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 extending from the wafer assembly and in fluid communication with respective ink supply channel groups, each group of nozzle arrangements comprising a pair of rows of nozzle arrangements and defining a pair of ink spread restriction pits extending between the rows.

2. A printhead as claimed in claim 1, wherein each group of nozzle arrangements comprises an ink spread restriction wall extending from the wafer assembly to border the pair of ink spread restriction pits.

3. A printhead as claimed in claim 2, wherein each ink ejection nozzle arrangement comprises:

a nozzle chamber structure arranged on the wafer assembly and defining a nozzle chamber for receiving ink from an ink supply channel and a raised nozzle rim through which ink in the nozzle chamber can be 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 so that, in use, the free end of the arm can be moved to eject ink in the nozzle chamber through the nozzle rim as a result of differential thermal expansion.

4. A printhead as claimed in claim 3, wherein the rows are arranged so that the thermal actuator mechanisms extend outwardly on either side of the nozzle chamber structures which, in turn, are centrally located.

5. A printhead as claimed in claim 3, 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.

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

7. A printhead as claimed in claim 3, wherein the thermal actuator mechanisms of one group of nozzle arrangements are interleaved with the thermal actuator mechanisms of an adjacent group of nozzle arrangements.

8. A printhead as claimed in claim 3, wherein the layers of conductive material are located proximal to the anchor.