Patents by Inventor Donald R. Holfeld

Donald R. Holfeld 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).

  • Stringline and cross-level gauge
    Patent number: 8222893
    Abstract: A tool and method for inspecting a track having a first rail and a second rail. The tool has a first mounting device which is attached to a first rail of the track. A cord attached to the mounting device is tensioned and positioning the cord in a proper position, allowing an inspector to measure a first distance between a defined point on the cord and the first rail or the second rail to determine if anomalies are present in the track.
    Type: Grant
    Filed: March 20, 2009
    Date of Patent: July 17, 2012
    Assignee: HARSCO Corporation
    Inventor: Donald R. Holfeld
  • STRINGLINE AND CROSS-LEVEL GAUGE
    Publication number: 20100237857
    Abstract: A tool and method for inspecting a track having a first rail and a second rail. The tool has a first mounting device which is attached to a first rail of the track. A cord attached to the mounting device is tensioned and positioning the cord in a proper position, allowing an inspector to measure a first distance between a defined point on the cord and the first rail or the second rail to determine if anomalies are present in the track.
    Type: Application
    Filed: March 20, 2009
    Publication date: September 23, 2010
    Applicant: HARSCO CORPORATION
    Inventor: Donald R. HOLFELD