Patents by Inventor Douglas D. Purdy

Douglas D. Purdy 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).

  • Chamber insulation for prevention of icing in air motors
    Patent number: 5649813
    Abstract: Insulation is provided in the form of wall insulation, piston or diaphragm insulation and/or piston rod and/or diaphragm washer insulation to increase the temperature in the working air chamber of an air motor of the piston or diaphragm type to reduce the formation of ice on exhaust.
    Type: Grant
    Filed: August 7, 1996
    Date of Patent: July 22, 1997
    Assignee: Ingersoll-Rand Company
    Inventors: Stephen D. Able, Douglas D. Purdy, Nicholas Kozumplik, Jr.
  • Diaphragm pump
    Patent number: D370488
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: June 4, 1996
    Assignee: The Aro Corporation
    Inventors: Nicholas Kozumplik, Jr., Robert C. Elfers, Douglas D. Purdy