Patents by Inventor Warren P. Williamson, IV

Warren P. Williamson, IV 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: 4965846
    Abstract: A pivot pin bearing/seal especially adapted for supporting the rotor of a disposable filtration cartridge of a continuous-flow plasmapheresis blood separation system includes a lubricious plastic pivot pin injection molded with a recess at its end. The recess is surrounded by a sharp circular inside edge. A stainless steel eyelet, deep drawn from successive dies, is loosely inserted into the pin recess, a radial outer surface defined at the junction between the eyelet shank and the eyelet flange contacting the pin sharp edge. The eyelet rotates relative to the pin, the circular line path of rotational contact being defined by the smooth curved surface under the flange of the eyelet and the sharp inside edge surrounding the pin recess which quickly burnishes to a good rotational seal.
    Type: Grant
    Filed: October 20, 1988
    Date of Patent: October 23, 1990
    Assignee: Baxter International Inc.
    Inventor: Warren P. Williamson, IV
  • Patent number: 4888004
    Abstract: Method and apparatus for purging air from a tubing network finds particular utility as a component part of a blood constituent processing system. Collection and return needles of a disposable tubing network are initially contained within a common antiseptic enclosure. A purge fluid (e.g., saline solution) may then be introduced into the interior chamber of the enclosure via one of the needles and withdrawn from the interior chamber via the other of the needles. Air entrained in the tubing network may thus be trapped within the common enclosure itself and/or vented therefrom via a one-way valve and hydrophobic microbe filter and/or the entrained air pockets may be encouraged to flow to a separate suitable air trap location of the tubing network whereby the network is purged of air.
    Type: Grant
    Filed: May 13, 1987
    Date of Patent: December 19, 1989
    Assignee: HemaScience Laboratories, Inc.
    Inventors: Warren P. Williamson, IV, Paul R. Prince
  • Patent number: 4816151
    Abstract: A disposable biomedical rotating filtration system for processing fluids in a closed environment includes a rotor mounted for rotation on a pivot pin, a seal between the rotor and pivot pin, an external permanent magnet drive mechanism, and a star shaped drive element mounted on the rotor for rotating the rotor in response to a magnetic field induced by the permanent magnet of the drive mechanism. The drive element on the rotor is stamped from an inexpensive non-permanent ferromagnetic sheet metal and has a configuration and position in relation to the center of said magnetic field such that said drive element receives sufficient torque for driving said rotor and sufficient seal force is applied on the rotor to provide fluid tight seal between the rotating rotor and the seal. The pivot pin is molded from a hard plastic material such as a polyamide base resin having a low coefficient of friction and good lubriciousness.
    Type: Grant
    Filed: July 29, 1987
    Date of Patent: March 28, 1989
    Assignee: Baxter International Inc.
    Inventors: Donald W. Schoendorfer, Warren P. Williamson, IV
  • Patent number: 4753729
    Abstract: A disposable biomedical rotating filtration system for processing fluids in a closed environment includes a rotor mounted for rotation on a pivot pin, a seal between the rotor and pivot pin, an external permanent magnet drive mechanism, and a star shaped drive element mounted on the rotor for rotating the rotor in response to a magnetic field induced by the permanent magnet of the drive mechanism. The drive element on the rotor is stamped from an inexpensive non-permanent ferromagnetic sheet metal and has a configuration and position in relation to the center of said magnetic field such that said drive element receives sufficient torque for driving said rotor and sufficient seal force is applied on the rotor to provide fluid tight seal between the rotating rotor and the seal. The pivot pin is molded from a hard plastic material such as a polyamide base resin having a low coefficient of friction and good lubriciousness.
    Type: Grant
    Filed: April 26, 1985
    Date of Patent: June 28, 1988
    Assignee: Baxter Travenol Laboratories, Inc.
    Inventors: Donald W. Schoendorfer, Warren P. Williamson, IV
  • Patent number: 4675106
    Abstract: In a disposable biomedical system for processing fluids in a closed environment such as a plasmapheresis system, comprising a plastic rotor mounted for rotation on a pivot pin bearing and a seal, particularly a silicone lubricated O-ring seal, between the rotor and pin, the improvement wherein said pivot pin is a molded pivot pin of a hard plastic material having a low coefficient of friction and lubriciousness, and which is capable of being irradiated by gamma radiation for sterilization and modification of the plastic material without degradation or loss of lubricious properties. The pivot pin bearing preferably comprises an injection molded polyamide based resin.
    Type: Grant
    Filed: April 12, 1985
    Date of Patent: June 23, 1987
    Assignee: Hemascience Laboratories, Inc.
    Inventors: Donald W. Schoendorfer, Warren P. Williamson, IV