US Patent 6971288 Automatically adjusting self-tightening wrench

A self-adjusting wrench having a handle and a jaw member rotationally attached thereto. A smoothly curved handle face opposes a planar face on the jaw member which adjusts for distance from the curved handle face by following a generally circular path around a pinned attachment of the jaw member to the handle. A spring or similar biasing device continuously urges the jaw member toward the handle thereby making the device self adjusting to the size of the object placed between the jaw member and the curved handle surface.