Hollow reaction torquemeter

Claim 1

A hollow reaction torquemeter comprising: a tubular torque transmitting member having a radial thin wall mid-portion, one end adapted to receive a torque, and an opposite end adapted to deliver a torque transmitted from said one end through said midportion to said opposite end; a tubular torque measuring tube spaced radially, coaxially of said torque transmitting member and having axially spaced portions, a radially thin portion intermediate said spaced portions and having a length a minor portion of the length of the torque measuring tube, said torque measuring tube including means for substantially eliminating bending moment effect defined by a groove portion intermediate said thin portion and each of said spaced portions, each said grooved portion being defined by a first, radially inwardly opening groove and a second, radially outwardly opening groove axially spaced adjacent said first groove; means fixedly securing said spaced portions to said torque transmitting member, said torque transmitting member and torque measuring tube being constructed so that a first major portion of a torque being transmitted between said torque transmitting member ends is transmitted through said torque transmitting member and a second, minor portion of the torque is transmitted through said torque measuring tube; and means for gauging a twist strain carried by said torque measuring tube thin portion for determining the amount of torque being transmitted through the torque measuring tube of the torquemeter.