Patents by Inventor Stuart Howkins

Stuart Howkins 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: 9944070
    Abstract: Determination of a maximum jetting frequency for an inkjet head. The method includes generating a velocity/frequency curve for an inkjet head, and determining failure zones in the velocity/frequency curve that comprise frequencies in the velocity/frequency curve resulting in jetting failure of the inkjet head. The method further includes determining a range of maximum jetting frequencies of the inkjet head that are higher than the frequencies of the failure zones, wherein subharmonic frequencies of each of the maximum jetting frequencies are outside of the failure zones. The method further includes selecting the maximum jetting frequency for the inkjet head from the range of maximum jetting frequencies.
    Type: Grant
    Filed: February 17, 2017
    Date of Patent: April 17, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Stuart Howkins, Charles Willus
  • Patent number: 4788557
    Abstract: An impulse ink jet apparatus includes a plurality of lengthwise expandable piezoelectric transducers, each of the transducers varying the volume of a compression chamber in order to eject droplets of ink therefrom. Mechanical cross talk propagating along a support structure for the transducers is minimized by effectively decoupling each transducer from its neighbors. In one approach, the support structure rigidly supports each transducer at displacement nodal points thereof, while in another approach the lengths of the transducers are uniquely varied with respect to their neighbors.
    Type: Grant
    Filed: March 9, 1987
    Date of Patent: November 29, 1988
    Assignee: Dataproducts Corporation
    Inventor: Stuart Howkins