Patents by Inventor Graham Higham

Graham Higham 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: 5146124
    Abstract: A linear drive motor of a cryogenic refrigerator, where a reciprocating armature is coupled to a piston which alternately compresses and expands a gaseous fluid in a thermodynamic cycle. The piston has a clearance seal and is attached at one end to a flexible coupling to reduce cross-bearing loads exerted by the piston along the clearance seal. A displacer assembly of the cryogenic refrigerator employs a displacer piston that reciprocates along a clearance seal. The displacer piston is coupled to the displacer cylinder and/or the armature of a displacer drive motor by a flexible coupling that reduces radial forces exerted by the displacer piston on the clearance seal.
    Type: Grant
    Filed: March 29, 1991
    Date of Patent: September 8, 1992
    Assignee: Helix Technology Corporation
    Inventors: Graham Higham, Niels Young, Alan Weeks, Steven A. Michaud, William Sand