Spiral wire bearing for rotating wire drive catheter

Claim 1

A catheter for introduction into a lumen in a living being to effect a procedure therein, said catheter being an elongated tubular flexible member having a distal end at which a working head is located, said catheter having an inner surface defining a passageway extending down said catheter, said working head being arranged for movement with respect to a central axis extending through said passageway, elongated drive means for said working head located within said passageway and extending down said catheter from a point adjacent said working head to a first remote proximal location, and an elongated bearing means for said drive means, said bearing means also located within said passageway and extending down said catheter from a point adjacent said working head to a second remote proximal location, one of said two last mentioned means being formed of at least a first wire and the other of said last two mentioned means being formed of a spiral of at least a second wire wrapped about said first wire, said second wire forming a helical space between its convolutions, whereupon said catheter can be readily bent through any arc up to a minimum radius of curvature while said drive means is rotated freely with respect to said bearing means and to said catheter at a high rotational speed to effect the movement of said working head with respect to said axis, said bearing means and said drive means cooperating with each other to maintain said drive means at a substantially neutral position within said catheter when said catheter is bent through said arc and rotated at said high rotational speed without resulting in undue vibration which could interfere with said procedure, said helical space being in communication with said inner surface and through which a cooling fluid may flow to contact said inner surface of said catheter and said first and second wires to expedite the rotation of said drive means with respect to said bearing means.