Patents by Inventor Stuart David Howkins

Stuart David 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: 6050679
    Abstract: Transducer arrays for use in multi-jet, drop-on-demand ink jet printers are formed of one or more thin plate-shaped layers of piezoelectric material. Electrodes are electrically coupled to the opposite facing flat plate surfaces of each layer, so as to provide an electric field in the direction orthogonal to the flat plate surfaces. The electric field causes the layer(s) of piezoelectric material to selectively contract or expand in the direction of the electric field. The selective expansion and contraction of the transducer is communicated, through a foot, to selectively contract and expand the volume of an ink-jet chamber. Contraction of the ink-jet chamber causes ink to be expelled through an orifice provided in communication with the ink-jet chamber. A plurality of transducers are arranged in a linear array corresponding to a linear array of ink-jet chambers and orifices.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: April 18, 2000
    Assignee: Hitachi Koki Imaging Solutions, Inc.
    Inventor: Stuart David Howkins