Patents by Inventor Darrell Darrow

Darrell Darrow 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: 6780369
    Abstract: A method of finishing concrete using a vibrating tool to consolidate a “dry shake” aggregate into the upper layer of the concrete. The use of the vibrating tool causes moisture within the concrete mass to migrate into the surface layer where the moisture may hydrate the aggregates in the dry shake mixture. The ability to cause upward migration of water in the concrete mass provides a larger window of finishability for the concrete. The vibrations also provide thorough consolidation of aggregates in the upper layer of the concrete mass helping to prevent delamination.
    Type: Grant
    Filed: August 2, 1999
    Date of Patent: August 24, 2004
    Assignee: Face International Corp.
    Inventors: Darrell Darrow, Glenn F. Rogers, Jr., Samuel A. Face, Jr., David Francis, Michael Davis, Yuting Wang
  • Patent number: 5527175
    Abstract: Vibrational energy introduced into plastic concrete structures, such as concrete slabs, decks and similar or related concrete structures, at or near the natural resonant frequency of the liquid concrete mass, expedites the consolidation and setting of the concrete. A vibrating apparatus imparts controlled vibrations either onto the surface or beneath the surface of the concrete mass in sequential stages, the frequency of vibrations generally increasing with each subsequent stage, corresponding to the increase in the natural resonant frequency of the progressively-narrowing liquid concrete at the top of the structure. The relatively more consolidated and more dry concrete (typically near the bottom of the slab) is substantially unaffected by the non-resonant frequencies vibrations. In one modification, sensors determine the resonant frequency of the liquid concrete mass during each pass of the vibrator apparatus, and the frequency of the vibrating member is automatically adjusted, accordingly.
    Type: Grant
    Filed: December 3, 1993
    Date of Patent: June 18, 1996
    Inventors: Samuel A. Face, Jr., Bradbury R. Face, Glenn F. Rogers, Jr., Darrell Darrow, Richard P. Bishop
  • Patent number: 5520862
    Abstract: Vibrational energy introduced into plastic concrete structures, such as concrete slabs, decks and similar or related concrete structures, at or near the natural resonant frequency of the liquid concrete mass, expedites the consolidation and setting of the concrete. A vibrating apparatus imparts controlled vibrations either onto the surface or beneath the surface of the concrete mass in sequential stages, the frequency of vibrations generally increasing with each subsequent stage, corresponding to the increase in the natural resonant frequency of the progressively-narrowing liquid concrete at the top of the structure. The relatively more consolidated and more dry concrete (typically near the bottom of the slab) is substantially unaffected by the non-resonant frequencies vibrations. In one modification, sensors determine the resonant frequency of the liquid concrete mass during each pass of the vibrator apparatus, and the frequency of the vibrating member is automatically adjusted, accordingly.
    Type: Grant
    Filed: December 3, 1993
    Date of Patent: May 28, 1996
    Inventors: Samuel A. Face, Jr., Bradbury R. Face, Glenn F. Rogers, Jr., Darrell Darrow, Richard P. Bishop