Patents by Inventor Donald S. de Vries, Jr.

Donald S. de Vries, Jr. 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).

  • Unitary rod gland assembly
    Patent number: 4261583
    Abstract: A rod gland assembly comprising a rod gland core made from a rigid material and adapted to be positioned in a cylinder, between the cylinder bore and a piston rod, and a multiple function seal/wiper/piston cushion element molded from a flexible material on the rod gland core, the multiple function element including a rod seal, a bore seal, a piston cushion, and a wiper/scraper.
    Type: Grant
    Filed: December 10, 1979
    Date of Patent: April 14, 1981
    Inventors: Donald S. de Vries, Jr., Jules M. Hock
  • One-piece plastic piston
    Patent number: 4214507
    Abstract: A piston comprising a core molded from a rigid thermoplastic material and a seal element molded on the core from a flexible thermoplastic material to form a unitary assembly.
    Type: Grant
    Filed: August 24, 1977
    Date of Patent: July 29, 1980
    Inventors: Jules M. Hock, Donald S. de Vries, Jr.