Torque Sensor Transdcuer

With full-scale ranges between 100 mNm and 10,000 Nm, the transducers utilize the Surface Acoustic Wave(SAW) phenomenon. This SAW approach has allowed the development of small transducers, which are not only exceptionally accurate, but, require no contact between the revolving shaft and its housing.In a TORQSENSE transducer, the surface waves are produced by passing an alternating voltage across the terminals of two interleaved comb-shaped arrays that are laid onto one end of piezoelectric substrate. A similar 'receiving' array, at the other end of the substrate, converts the wave into an electric signal.The frequency generated is dependant on the spacing of the 'teeth' in the array and as the direction of the wave propagation is at right angles to the teeth, any change in length alters the spacing of the teeth and the operating frequency.To measure torque, two SAW sensors are bonded rigidly to a shaft at 45 degrees to the axis and connected in a half bridge configuration, so that when the shaft is subjected to a torque, outputs are combined to produce a 'difference' signal proportional to applied torque. This signal is exchanged via a capacitive rotor and stator.TORQSENSE transducers require minimum length of shaft, have low inertia, no physical contact between shaft and housing, wide bandwidth, high resolution and accuracy, and excellent noise immunity. OEM transducers can be designed for specific applications.The transducers are available with RPM output and IP65 sealing, and interface with the E302 Advanced Torque Transducer Display, which features full temperature correction for changes in the modulus of elasticity of the shaft and TORQVIEW Virtual Instrumentation Software.