Patents by Inventor Donald L. Hollenbeck

Donald L. Hollenbeck 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).

  • Drainage system monitoring apparatus
    Patent number: 4935726
    Abstract: This invention is directed to an apparatus or system which is used for monitoring a storm drain system in order to detect the presence of hydrocarbons or the like therein. The apparatus includes a sensor unit which is arranged to float on the surface of the storm drain effluent. A suitable alarm system is connected to the sensor unit to indicate an activation of the sensor unit. The storm drain is, typically, modified to provide a uniform sensing area adjacent to the sensor unit.
    Type: Grant
    Filed: December 14, 1988
    Date of Patent: June 19, 1990
    Assignee: Underground Sensor Systems, Inc.
    Inventors: Timothy Buro, Donald L. Hollenbeck, Robert A. Rauch