EXPANDED RANGE MONOPOLE TORQUE MEASURING SYSTEM

摘要

A torque measurement system for measuring shaft torque has two toothed wheels mounted in spaced apart relationship. Each of the wheels has a plurality of axially extending spaced teeth along its periphery extending into spaces between the teeth of the other, forming an interlaced array of teeth having tooth spacing interstices therebetween. A discontinuity is provided in the tooth pattern at at least one location around the periphery of the two wheels to serve as an index marker. A single detector such as a variable relunctance sensor is mounted proximate the wheels to provide output signals representative of circumferential widths of tooth spacing interstices and also representative of the index marker. The widths of the interstices change upon shaft torque deflection, and signals from the sensor are processed to produce a DC signal proportional to torque. The two wheels can be offset in a no load condition so that adjacent tooth spacing interstices are approximately equal in a torque deflection range of interest.