Ink printhead nozzle arrangement with volumetric reduction actuators

• US 7,347,536 B2
• Filed: 01/22/2007
• Issued: 03/25/2008
• Est. Priority Date: 06/09/1998
• Status: Expired due to Fees

• Current Assignee: Memjet Technology Ltd. (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia, McAvoy, Gregory John
• Primary Examiner(s): Do; An H.
• Application Number:
  US11/655,987
• Publication Number:
  US 20070115328A1
• Time in Patent Office: 428 Days
• Field of Search: 347/54, 347/65
• US Class Current: 347/54
• CPC Class Codes: B41J 2/1433 Structure of nozzle plates
• 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 2/1629 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 2/1648 Production of print heads with thermal bend detached actuators
• 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 2002/14475 characterised by nozzle shapes or number of orifices per chamber
• CPC Class Codes: B41J 2202/15 Moving nozzle or nozzle plate
• CPC Class Codes: Y10T 29/49401 Fluid pattern dispersing device making, e.g., ink jet

Abstract

An ink jet printhead nozzle arrangement includes a wafer substrate that defines side walls and an inlet opening of an ink chamber. Drive circuitry is arranged on the wafer substrate A. roof wall assembly defines a roof of the ink chamber and an ink ejection port in fluid communication with the ink chamber. The roof wall assembly includes a nozzle rim supported in general alignment with the inlet opening. A series of radially positioned actuators are each connected to the substrate to receive electrical drive signals, with free ends of the actuators terminating proximate the nozzle rim. The actuators are configured so that, on receipt of an electrical signal from the drive circuitry, said free ends of the actuators are displaced into the ink chamber to reduce a volume of the ink chamber and to eject ink from the ink ejection port.

Claims

1. An ink jet printhead nozzle arrangement comprising:

a wafer substrate that defines side walls and an inlet opening of an ink chamber;

drive circuitry arranged on the wafer substrate;

a roof wall assembly defining a roof of the ink chamber and an ink ejection port in fluid communication with the ink chamber, the roof wall assembly comprising

a nozzle rim supported in general alignment with the inlet opening; and

a series of radially positioned actuators that are each connected to the substrate to receive electrical drive signals, with free ends of the actuators terminating proximate the nozzle rim, the actuators being configured so that, on receipt of an electrical signal from the drive circuitry, said free ends of the actuators are displaced into the ink chamber to reduce a volume of the ink chamber and to eject ink from the ink ejection port.

2. An ink jet printhead nozzle arrangement as claimed in claim 1, in which the side walls are the product of a crystallographic etching process carried out on the wafer substrate.

3. An ink jet printhead nozzle arrangement as claimed in claim 1, in which each actuator is in the form of a layer of a polymer with a heater core connected to the drive circuitry, the heater core being positioned so that when the polymer is heated, the actuator experiences differential thermal expansion to generate said displacement of the free end.

4. An ink jet printhead nozzle arrangement as claimed in claim 3, in which the polymer is polytetrafluoroethylene.

5. An ink jet printhead nozzle arrangement as claimed in claim 3, in which each heater core is in the form of a serpentine heating circuit of one of copper and aluminum.

6. An ink jet printhead nozzle arrangement as claimed in claim 1, in which the drive circuitry is at least partially defined by a ceramic metal oxide semiconductor (CMOS) layer positioned on the wafer substrate.

7. An ink jet printhead nozzle arrangement as claimed in claim 1, in which the ink inlet opening is the product of a back-etching process carried out on the wafer substrate.