Patents Represented by Attorney, Agent or Law Firm Jeffrey E. Sempreben
  • Bolt centralizer
    Patent number: 6598309
    Abstract: A bolt centralizer for a rock bolter, which advances a bolt along a work axis, has a hand pivotably mounted on an arm so as to pivot between first and second hand positions. A pair of fingers is pivotably attached to the hand. When the fingers are in a closed position, they form a centralizer passage which is aligned with the work axis when the hand is in the first hand position. The hand is pivoted to the second hand position to remove the fingers from the bolt to allow a bolt plate and bolt driver to be advanced past the hand.
    Type: Grant
    Filed: April 30, 2002
    Date of Patent: July 29, 2003
    Assignee: Oldenburg Cannon, Inc.
    Inventor: Perry L. Coombs