Patents by Inventor Douglas C. Duffy

Douglas C. Duffy 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).

  • Drum or pail closure
    Patent number: 5086944
    Abstract: The invention comprises a drum having a top rim formed as an outwardly rolled curl. The curl is rolled through at least 450 degrees with respect to the cylindrical wall of the drum and does not contact any uncurled portion of the body of the drum.
    Type: Grant
    Filed: August 22, 1988
    Date of Patent: February 11, 1992
    Assignee: Rheem Autralia Ltd.
    Inventors: Douglas C. Duffy, Richard D. Temby
  • Method of forming a drum or pail closure
    Patent number: 4938051
    Abstract: The formation of an outwardly extending curl as the upper rim of a pail or drum having a cylindrical wall by curling the peripheral edge through greater than 360.degree. relative to the cylindrical wall forms a strong curl able to support, with the aid of a gasket, a leak proof seal during dangerous goods testing. When used with a lug-cover lid, the lugs may be clenched beneath the curl through a re-entrant portion enhancing the security of the seal. Methods of forming the curl in a two-storage operation by forming primary and then secondary curl components, and an improved lug configuration are also described.
    Type: Grant
    Filed: August 6, 1986
    Date of Patent: July 3, 1990
    Assignee: Rheem Australia Limited
    Inventors: Douglas C. Duffy, Richard D. Temby