Patents by Inventor Gerald D. St. John

Gerald D. St. John 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: 4468321
    Abstract: The filter device is for filtering liquids and has a reservoir member for receiving the liquid to be filtered and a spout member for exit of the liquid after it is filtered, the spout member being assembled to the reservoir member with a filter disc therebetween. Each of these members has an annular ceramic magnet, these ceramic magnets being adjacent each other when the members are assembled whereby the magnetic attraction sealingly clamps the filter disc between the members. In accordance with the invention, the annular ceramic magnet of the reservoir member is completely enclosed within a closed annular cavity in the organic plastic of the reservoir member, the annular magnet being of smaller size than the annular cavity; and the annular ceramic magnet of the spout member is completely enclosed within a closed annular cavity in the organic plastic of the spout member, this annular magnet also being of smaller size than the annular cavity in which it is enclosed.
    Type: Grant
    Filed: February 17, 1983
    Date of Patent: August 28, 1984
    Assignee: Gelman Sciences Inc.
    Inventor: Gerald D. St. John