Patent ID: 7210210

Claim:
A method of forming an annularly expanding and retracting gripping and releasing mechanism suitable for use as a stone extractor or medical where grasper comprises an annular array of fixed flexure elements fixed together at proximal ends thereof and corresponding movable flexure elements fixed with respect to distal ends of respective fixed flexure elements and movable within respective adjacent fixed flexure elements so that (1) movement of said movable flexure elements outwardly of said fixed flexure elements causes said fixed flexure elements to flex transversely outwardly and create an expanded condition defined by an annular series of transversely outwardly flexed fixed flexure elements interconnected by an annular series of arcuately flexed portions of said movable flexure elements; and (2) movement of said movable flexible elements when in an expanded condition in a direction inwardly of the fixed flexure elements causes the expanded condition to progressively retract, said method comprising: providing (1) a series of flexible tubular structures; (2) a corresponding series of wires, each of which includes a movable wire section and relatively short fixed wire section integrally connected with one end of the movable wire section by a kink configured so that said wire sections extend in longitudinally coextensive relation therefrom; (3) a series of tubular elements of thermoplastic material; and (4) a series of heat shrinkable sleeves; assembling a movable wire section within each flexible tubular structure and a distal end portion of each flexible tubular structure with a fixed wire section, a tubular element and a heat shrinkable sleeve so that (1) the fixed wire section extends along the exterior periphery of the flexible tubular structure with the kink disposed outwardly of the distal end thereof; (2) the tubular element is disposed in surrounding relation to the fixed wire section and the flexible tubular structure; and (3) the heat shrinkable sleeve is disposed in surrounding relation to the tubular element, and applying heat to the exterior of each heat shrinkable sleeve at a temperature sufficient to contract the sleeve and soften the thermoplastic material of the tubular element surrounded thereby so that the contraction of the sleeve molds the softened thermoplastic material into adhered contact with the exterior surfaces of the surrounded fixed wire section and flexible tubular structure, and fixedly securing said flexible tubular structures together adjacent the proximal ends of the heat shrinkable sleeves disposed in surrounding relation to said tubular elements.