Patents by Inventor David Dwight Mulligan

David Dwight Mulligan 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).

  • Debarking wood without introducing contaminants into the wood
    Patent number: 5868186
    Abstract: This invention relates to a wood chip recovery system which removes bark from roundwood or wood chips. It is desirable for such structures of this type to recover the wood chips from the bark without introducing contaminants, such as metal ions like iron, into the debarked roundwood or wood chips.
    Type: Grant
    Filed: September 11, 1997
    Date of Patent: February 9, 1999
    Assignee: Westvaco Corporation
    Inventors: David Dwight Mulligan, John Rolfe Hite Martin
  • Debarking and chipping folded whole-trees
    Patent number: 5803142
    Abstract: This invention relates to debarking and chipping folded whole trees. Such structures of this type, generally, increase wood recovery by making high-quality chips out of tree tops, branches, as well as, other larger portions of the tree.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: September 8, 1998
    Assignee: Westvaco Corporation
    Inventors: David Dwight Mulligan, James Ernest Salyers