Patents by Inventor Stanley D. Robinson

Stanley D. Robinson 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: 5337842
    Abstract: A drill steel is provided for use in percussive drilling. The drill steel has an elongate body for transmitting energy between a drill rig and a drill bit, and each end of the drill steel has an end coupling portion. The body has a means for reducing vibrations at the end coupling portions comprising a twisted portion between the two ends. The twisted portion transmits less vibration than untwisted drill steel of corresponding size under the same conditions. The twisted portion also promotes bending in the drill steel in at least two or more places. The twisted portion may have a helical pitch of between one half turn over the length of the drill steel and two turns per foot. The twist may be of uniform or variable pitch, or a combination thereof.
    Type: Grant
    Filed: July 13, 1992
    Date of Patent: August 16, 1994
    Inventor: Stanley D. Robinson