Anvil assembly for a power tool

An anvil assembly for a tool, the tool including a tool element for working on a workpiece, the anvil assembly comprising:

• an anvil including
• a body having a cylindrical outer periphery defining a longitudinal axis,
• a head formed on a distal end of the body, the head including
• a substantially planar distal end surface,
• at least two substantially planar surfaces upon which the tool element is supportable,
• a detent aperture extending through one of the substantially planar surfaces substantially transverse to the longitudinal axis,
• an arcuate surface contiguous with the substantially planar surfaces and proximate the cylindrical outer periphery,
• a corner disposed adjacent the substantially planar surfaces,
• a detent element located in the detent aperture;
• and
• a sleeve surrounding at least a portion of the outer periphery of the body, the sleeve having a distal end against which the tool element is abutted when the tool element is coupled to the head;
• wherein the corner, at a location on the head between the detent element and the substantially planar distal end surface, is defined by one of a radius and a taper for transferring stress surrounding the detent aperture toward the arcuate surface of the head.