Patent ID: 7318776

Claim:
A torque limiter comprising: an annular outer member having a boss portion at a first end thereof; an inner ring inserted in said annular outer member and supported by said boss portion so as to be rotatable relative to said annular outer member; a coil spring having a uniform diameter and interference-fitted on a radially outer surface of said inner ring; and a lid member fitted in said annular outer member at a second end thereof, thereby closing a gap between said radially outer surface of said inner ring and a radially inner surface of said annular outer member, such that said lid member is rotatable relative to said inner ring; wherein said coil spring is constituted by a wire formed into a coil configuration, said wire has a wire axis extending longitudinally therealong, said wire has two wire end faces at opposite ends thereof, and said two wire end faces are substantially perpendicular to said wire axis at said opposite ends of said wire, respectively; wherein said boss portion has an axially inner end face formed with a first protrusion configured to engage one of said two wire end faces of said wire of said coil spring; and wherein said lid member has an axially inner surface formed with a second protrusion configured to engage the other of said two wire end faces of said wire of said coil spring.