Patents by Inventor James Edward David Marchant

James Edward David Marchant has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10214009
    Abstract: An inkjet printhead comprising a printhead die, the printhead die comprising: a plurality of actuators; a plurality of electrical connections in electrical communication with respective first electrodes of the plurality of actuators for providing drive signals thereto; a first electrical bus arranged in common electrical communication with second electrodes of a first group of the actuators for providing first signals thereto; and a second electrical bus arranged in common electrical communication with second electrodes of a second group of the actuators for providing second signals thereto.
    Type: Grant
    Filed: June 3, 2016
    Date of Patent: February 26, 2019
    Assignee: Xaar Technology Limited
    Inventors: Robert Errol McMullen, James Edward David Marchant, Subramanian Sivaramakrishnan
  • Publication number: 20180170037
    Abstract: An inkjet printhead comprising a printhead die, the printhead die comprising: a plurality of actuators; a plurality of electrical connections in electrical communication with respective first electrodes of the plurality of actuators for providing drive signals thereto; a first electrical bus arranged in common electrical communication with second electrodes of a first group of the actuators for providing first signals thereto; and a second electrical bus arranged in common electrical communication with second electrodes of a second group of the actuators for providing second signals thereto.
    Type: Application
    Filed: June 3, 2016
    Publication date: June 21, 2018
    Inventors: Robert Errol MCMULLEN, James Edward David MARCHANT, Subramanian SIVARAMAKRISHNAN
  • Patent number: 9579890
    Abstract: A printhead for a printer has actuating elements for ejecting fluid, and a drive circuit for selectively applying a drive waveform having several slopes, to an actuating element, according to a print signal. A resulting printhead has a lesser sensitivity to changes of slew rate in one slope of the drive waveform than a sensitivity to change in another. The drive circuit has a variable resistance circuit, and a control circuit to control the variable resistance circuit to adjust a slew rate of the slope of lesser sensitivity according to a trim signal. By making the adjustment less sensitive, the trim signal and trim control can have more relaxed tolerances, thus can employ simpler, cheaper circuitry.
    Type: Grant
    Filed: September 10, 2015
    Date of Patent: February 28, 2017
    Assignee: XAAR TECHNOLOGY LIMITED
    Inventors: James Edward David Marchant, Stephen Mark Jeapes, Ian Anthony Hurst
  • Patent number: 9399342
    Abstract: A printhead provides actuation pulses for driving actuating elements from a common drive waveform via respective switching circuits, the waveform having a pre-charge ramp followed by a steeper slope. A start voltage of a leading edge of the actuation pulse is set by opening the switching circuit to decouple the common drive waveform from its actuating element part way along the pre-charge ramp. After the pre-charge ramp the actuating element is coupled again to the common drive waveform, so that the voltage across the actuating element follows the steeper slope to form the leading edge. Adjusting the timing of the decoupling adjusts the start voltage, enables trimming relative to other actuating elements. The gentle slope of the pre-charge ramp enables the precision of timing of switching to be more relaxed, so that trigger circuitry for controlling the switching circuit can be simpler, smaller, cheaper and thermally more efficient.
    Type: Grant
    Filed: September 10, 2015
    Date of Patent: July 26, 2016
    Assignee: Xaar Technology Limited
    Inventor: James Edward David Marchant
  • Publication number: 20160067960
    Abstract: A printhead for a printer has actuating elements for ejecting fluid, and a drive circuit for selectively applying a drive waveform having several slopes, to an actuating element, according to a print signal. A resulting printhead has a lesser sensitivity to changes of slew rate in one slope of the drive waveform than a sensitivity to change in another. The drive circuit has a variable resistance circuit, and a control circuit to control the variable resistance circuit to adjust a slew rate of the slope of lesser sensitivity according to a trim signal. By making the adjustment less sensitive, the trim signal and trim control can have more relaxed tolerances, thus can employ simpler, cheaper circuitry.
    Type: Application
    Filed: September 10, 2015
    Publication date: March 10, 2016
    Inventors: James Edward David Marchant, Stephen Mark Jeapes, Ian Anthony Hurst
  • Publication number: 20160067961
    Abstract: A printhead provides actuation pulses for driving actuating elements from a common drive waveform via respective switching circuits, the waveform having a pre-charge ramp followed by a steeper slope. A start voltage of a leading edge of the actuation pulse is set by opening the switching circuit to decouple the common drive waveform from its actuating element part way along the pre-charge ramp. After the pre-charge ramp the actuating element is coupled again to the common drive waveform, so that the voltage across the actuating element follows the steeper slope to form the leading edge. Adjusting the timing of the decoupling adjusts the start voltage, enables trimming relative to other actuating elements. The gentle slope of the pre-charge ramp enables the precision of timing of switching to be more relaxed, so that trigger circuitry for controlling the switching circuit can be simpler, smaller, cheaper and thermally more efficient.
    Type: Application
    Filed: September 10, 2015
    Publication date: March 10, 2016
    Inventor: James Edward David Marchant