Patent ID: 7607497
Filing Date: 2009-10-27
Classification: E21B

Abstract:
1. An expandable assembly for anchoring a tool in a passage, said expandable assembly comprising a first tractor for moving a tool through a passage, said first tractor comprising: an elongate body defining a first longitudinal axis; and an expandable gripper assembly comprising: wherein movement of said first actuation assembly causes said roller mechanism to move away from the second end of said roller link and toward said first end of said roller link so that said roller mechanism pushes said inner surface of said roller link thereby causing said roller link to pivot away from said elongate body about said first end of the roller link and wherein movement of said second actuation assembly pushes said second end of said toggle link toward said first end of said roller link; and at least one propulsion assembly configured to advance said elongate body through the passage relative to said expandable gripper assembly.