Inkjet printhead comprising actuator spaced apart from substrate

• US 7,971,975 B2
• Filed: 10/25/2009
• Issued: 07/05/2011
• 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): Do; An H
• Application Number:
  US12/605,353
• Publication Number:
  US 20100039478A1
• Time in Patent Office: 618 Days
• Field of Search: 347/9, 347/17, 347/54, 347/56, 347/62, 347/65
• US Class Current: 347/62
• CPC Class Codes: B41J 2/04505 aiming at correcting alignment
• CPC Class Codes: B41J 2/04516 preventing formation of satellite drops
• CPC Class Codes: B41J 2/04518 reducing costs
• CPC Class Codes: B41J 2/0452 reducing demand in current or voltage
• 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 2/04565 detecting heater resistance
• CPC Class Codes: B41J 2/0457 Power supply level being detected or varied
• 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 2/0459 Height of the driving signal being adjusted
• CPC Class Codes: B41J 2/04591 Width of the driving signal being adjusted
• CPC Class Codes: B41J 2/04593 Dot-size modulation by changing the size of the drop
• CPC Class Codes: B41J 2/04596 Non-ejecting pulses
• CPC Class Codes: B41J 2/04598 Pre-pulse
• CPC Class Codes: B41J 2/14427 Structure of ink jet print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2/155 : for line printing
• 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 2/1646 : thin film formation by sputtering
• CPC Class Codes: B41J 2/1648 : Production of print heads with thermal bend detached actuators
• CPC Class Codes: B41J 2002/14491 : Electrical connection
• CPC Class Codes: B41J 25/005 : for serial printing movements superimposed to character- or line-spacing movements
• CPC Class Codes: G06K 15/102 : using ink jet print heads
• CPC Class Codes: Y10T 29/49401 : Fluid pattern dispersing device making, e.g., ink jet

Abstract

An inkjet printhead including a substrate and a plurality of nozzle assemblies disposed on the substrate. Each nozzle assembly includes a nozzle chamber for containing ink and an actuator for ejecting an ink droplet from a nozzle aperture when a resistive element of the actuator is heated by an electrical current. The resistive element of the actuator is spaced apart from the substrate and suspended in ink contained in the nozzle chamber.

Claims

1. An inkjet printhead comprising a substrate and a plurality of nozzle assemblies disposed on said substrate, each nozzle assembly comprising:

a nozzle chamber for containing ink, said nozzle chamber having a nozzle aperture for ejection of ink and an ink inlet; and

an actuator for ejecting an ink droplet from the nozzle aperture when a resistive element of said actuator is heated by an electrical current, wherein the resistive element of said actuator is spaced apart from said substrate and suspended in ink contained in said nozzle chamber.

2. The printhead of claim 1, wherein said substrate is a silicon substrate comprising one or more integrated CMOS layers.

3. The printhead of claim 1, wherein each nozzle assembly has associated therewith:

a drive transistor for providing an energy pulse to said resistive element of said actuator; and

control logic for controlling said drive transistor.

4. The printhead of claim 3, wherein said resistive element is positioned over at least one of said drive transistor and control logic.

5. The printhead of claim 1, wherein said printhead comprises at least one temperature sensor, and wherein a sensed temperature is used to determine an amount of electrical energy supplied to each heating element.

6. The printhead of claim 1, wherein said printhead is comprised of a plurality of abutting printhead integrated circuits.

7. The printhead of claim 1, wherein said resistive element is comprised of titanium nitride.

8. The printhead of claim 1, wherein said nozzle chamber is comprised of ceramics.