Patents by Inventor Frederick C. Greenwood

Frederick C. Greenwood 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).

  • Contraceptive and prophylactic device
    Patent number: 4945923
    Abstract: A contraceptive device adapted to be worn by a female, and which serves to prevent the exchange of body fluids during intercourse, is disclosed. A preferred embodiment of the device has an elongate tubular sheath formed of thin, fluid impermeable material, the sheath having a closed inner end portion and an open outer end portion. A resilient inner ring is connected to the inner end portion for anchoring the same to the cervix of a wearer. An outer ring is connected to the open outer end portion for maintaining the outer end portion in an open configuration.
    Type: Grant
    Filed: July 10, 1989
    Date of Patent: August 7, 1990
    Inventors: Mark I. Evans, Frederick C. Greenwood