Patents by Inventor Leonard D. Trowbridge

Leonard D. Trowbridge 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: 4019270
    Abstract: A picture frame clamp having four corner brackets for holding the respective corners at a right angular relationship. The four corner brackets are four diagonally extending strap lengths which are connected adjacent the intersecting ends thereof by an adjustment screw to firmly clamp the corners together in a right angular relationship.The straps are connected to the corners so as to be capable of varying the length thereof to the clamp at the intersection thereby to permit the clamp to be adaptable for use for different picture frames.
    Type: Grant
    Filed: March 27, 1975
    Date of Patent: April 26, 1977
    Inventor: Leonard D. Trowbridge
  • Patent number: 3962949
    Abstract: A twirling baton with a handle mounted on an axis extending perpendicular to the axis of the baton shaft by which the baton may be twirled with minimal effort, said handle being equipped with braking means to quickly stop the rotation of the baton when desired.
    Type: Grant
    Filed: February 27, 1975
    Date of Patent: June 15, 1976
    Inventors: Leonard D. Trowbridge, Naomi A. Trowbridge