Patents by Inventor Dennis H. Pengelly

Dennis H. Pengelly 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: 5801732
    Abstract: An ink jet apparatus comprising an array of impulse ink jets is disclosed. Each of the ink jets includes a chamber having an orifice and a transducer coupled to the chamber, a signal generator applying firing signals to each transducer of each of the ink jets to eject droplets of ink on demand, and a controller for controlling the phase of the firing signals to prevent the simultaneous application of the firing signals to adjacent ink jets in the array. The orifices are linearly aligned and adjacent ink jets produce ink drops offset by less than the diameter of the drops. The natural ringing of the piezo crystals of the ink jet transducers has been found to occur at a frequency of about 46 kHz (period=22 .mu.s), and so a delay of about 25 ms, one-half the ringing period, is used to minimize cross-talk among neighboring channels.
    Type: Grant
    Filed: November 2, 1995
    Date of Patent: September 1, 1998
    Assignee: Dataproducts Corporation
    Inventor: Dennis H. Pengelly