Wire driver handpiece

In a surgical instrument for rotatably driving an elongated rodlike tool, such as a wire, comprising:

• a manually graspable hollow casing comprising a tool handle;
• a shaft rotatably supported within said casing and arranged to be rotatably drive about its axis by a source of rotative power, said shaft having an enlarged shaft portion positioned adjacent and projecting axially outwardly from the front end of said casing, said enlarged shaft portion having an axially elongated interior opening formed therein and extending divergingly through the forward end of said shaft portion, said opening being bounded by a frusto conical surface positioned at a small angle with respect to the axis of said shaft;
• a tool carrier positioned coaxially with and partially telescoped into said interior opening, said tool carrier having a central opening extending axially therethrough in substantially coaxial alignment with said shaft, said tool carrier also having three slots extending radially therethrough from said central opening to the exterior peripheral surface of said tool carrier, said three slots being circumferentially spaced apart and disposed with the radial center lines thereof within substantially a single plane which extends perpendicularly to said axis;
• three clamping members positioned respectively within said slots and adjacent said conical surface for responding to axial movement of said tool carrier along and with respect to said conical surface for effecting movement of said clamping members radially of said tool carrier, said clamping members entering at least partially into said central opening in at least one axial position of said tool carrier for clamping engagement with a rodlike tool positioned therein;
• two of said clamping members comprising identical balls and the third clamping member comprising a disk which is so related relative to its respective slot that the axis of said disk is spaced from but substantially perpendicular to the axis of said tool carrier, said disk and said balls all being of the same diameter, and said disk having a peripheral surface adapted for engagement with the tool which is of a rounded convex configuration in the axial direction of the disk;
• whereby upon rearward axial movement of said tool carrier into said interior opening, said clamping members will grip a tool positioned within said tool carrier and upon forward axial movement of said tool carrier, said clamping members will release said tool.