Patent ID: 6869366

Claim:
A universal joint to transmit force from a tool to a workpiece comprising: a driver attachable to the tool, the driver having a spherical cavity formed therein, a plurality of equi-spaced apart inwardly extending protrusions disposed circumferentially and approximately equatorially within the cavity about a central axis, a driven socket having a first end and an opposite second end, the first end having means thereon to drive the workpiece, the second end being spherical disposed on the central axis, a neck being formed between the first end and the second end about the central axis, the second end having a plurality of spaced-apart channels, each channel being parallel to the central axis, each channel being formed from a first drive web and a second drive web, each connected angularly to a drive shank within the respective channel, wherein a plurality of drive webs are alternatively disposed forming the plurality of channels, the plurality of channels equaling the plurality of spaced-apart protrusions in the driver wherein the second end of the driven socket is received in the cavity in the driver, each protrusion within the cavity having a pair of separated conical sidewalls, each sidewall having a decreasing radius as the protrusion extends toward the central axis of the driver, an angled ramp separating the pair of conical sidewalls, a crown radius being formed at a top of the ramp, wherein the conical sidewalls of the protrusions provide a tangential contact area for the channels of the spherical second end of the driven socket.