Patent ID: 7387175

Claim:
Apparatus for mounting on the end of a drill string having a rotatable distal end in a wellbore, the apparatus comprising: a reamer, at least a portion of which has a rotatable abrasive reaming tube thereon, the abrasive reaming tube having a bore, the bore adaptable for receiving a core; a non-rotating mandrel extending along the bore of the abrasive reaming tube, the abrasive reaming tube being rotatable about the mandrel; a non-rotating lower lateral displacement means connected to a lower end of the mandrel and operable to displace the reamer between a non-displaced position and a laterally displaced position; and an upper lateral displacement means adapted for connection to the rotatable distal end of the drill string and connected to an upper end of the reamer for driveably rotating the abrasive reaming tube and for displacing the reamer between a non-displaced position and a laterally displaced position; and a fluid passage through the upper lateral displacement means and the reamer for supplying drilling fluids from the drill string to a downhole end of the abrasive reaming tube, and wherein when the lower and upper lateral displacement means are in the non-displaced position, the reamer and abrasive reaming tube are aligned in the wellbore; and when the lower and upper lateral displacement means are actuated to the laterally displaced position, the reamer and abrasive reaming tube are positioned substantially parallel to the wellbore for milling a window in a sidewall of the wellbore.