Patents by Inventor Corwin M. Tromp

Corwin M. Tromp 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: 4799381
    Abstract: A sensor used for detecting the passage of vehicles over a roadway is formed of a force sensing variable resistor which is embedded in a resilient, rubber-like strip that is molded around the resistor within an elongated sheet metal channel. The channel is sized to fit within a narrow saw-cut groove across the roadway, so that the strip exposed surface at the open top of the channel is exposed at the road surface for contact by the tires of passing vehicles. The resistor is formed of a printed circuit having a pair of separated conductive stripes with a repetitive pattern of gap areas between them, and a sheet of variable resistance material overlying each of the gap areas to form conductive shunts between the printed conductive stripes.
    Type: Grant
    Filed: February 21, 1988
    Date of Patent: January 24, 1989
    Assignee: CMI International, Inc.
    Inventor: Corwin M. Tromp