Patents by Inventor Hermann L. Hofmann

Hermann L. Hofmann 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).

  • Apparatus for clearing drains
    Patent number: 4097937
    Abstract: A device for clearing drains has an air reservoir which may be filled from an external source of compressed air, a rubber cup connected by a neck into the base of the reservoir, and a valve stem passing through the neck and connecting a valve member within the reservoir and normally seated on and closing the neck with an actuator member within the cup.
    Type: Grant
    Filed: May 2, 1977
    Date of Patent: July 4, 1978
    Inventor: Hermann L. Hofmann