Patents by Inventor James Duignan

James Duignan 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).

  • Publication number: 20190240720
    Abstract: Operation of a cutting mechanism provides an annular gasket or washer from a suitable solid gasket or washer material. The cutting mechanism includes a body defining a passage with an opening and a cutting head. The cutting head translationally retracts into the passage through the opening and projects from the passage through the opening along a longitudinal axis of the mechanism. The cutting head carries multiple cutters and can be selectively rotated about the axis when projecting through the opening from the passage. The position of each of the cutters is adjustable along a radial range of distances from the axis to correspondingly set an inner diameter and an outer diameter of the gasket or washer.
    Type: Application
    Filed: February 7, 2018
    Publication date: August 8, 2019
    Inventor: James Duignan
  • Patent number: 6437698
    Abstract: A smoke alarm device has an ASIC (1) with an integrated photo detector (3) and control circuit. The photo detector output is compared every ten seconds with an alarm threshold level in a comparator circuit (10), with a sensitivity-decrease threshold in a comparator circuit (11), and with a sensitivity-increase threshold in a comparator circuit (12). A logic block (2) causes sensitivity to be increased or decreased in which decreases take place at intervals of six hours and increases take place after 40 secs. The logic block (2) provides for least sensitivity at power-up with rapid increases to the appropriate level according to the level of back-scatter caused by dust contamination. The logic block (2) maintains a high signal on an interconnect terminal (9) for four seconds after a test button (7) is pressed so that a maintenance person can hear remote interconnected devices after the local device has stopped sounding.
    Type: Grant
    Filed: November 6, 2000
    Date of Patent: August 20, 2002
    Assignee: E.I. Technology Limited
    Inventors: Michael Byrne, James Duignan, Keith Fawcett, Fergus Flynn, Michael Guinee