Research On The Principle And The Structural Analysis Of The Ring-ball-gird Torque Sensor

Torque is one of the important parameters of the totating machinery.Measuring the torque,people would find out the performance of the drive system,and can provide powerful evidences for safety warning of system,improving machine and optimizing efficiency. At present,there have many methods for measuring torque at home and abroad.But the study on torque sensor used at the worst working conditions is a weakness point.For dynamic measuring of the torque of mechanical axes under severe working environments,the paper gave a new design idea of the detector that was more consistent with the requirements of the sensor based on a torque sensor composed of a ring-ball-grid and a magnetic-electric detector,funded by"Research on dynamic characteristics of mechanical transmission system under extreme environment",the project of Natural Science Foundation of Chongqing.First,linked with the structural characteristics of the sensor and the principle of the magnetic track,the paper pivoted around a deep research on this new design of non-contact torque sensor and ANSYS software in modeling was used to make the electromagnetic analysis for finding out the characteristics and disciplines of the output signal and providing a basis on further design and dynamic measurement of torque under extreme environment of the sensor.Finally,signal measurement of the model sensor was analysed on the platform of drive system.Firstly, the paper discussed the roads of the values between torque and the measured parameters according to the technology of Spherosyn Linear Encoders. Secondly,on the basis of the especial structure of the ring-ball-grid and the principle of the magnetic track,the paper established measurement principle of ball-induced detector under the condition of especial excitation system,and also gave the mathematical relation between the induced potential of the detector and the value of the magnetic air gap.And then,the paper studied the relation between the magnetic air gap and torsion angle,and finished the theory system of the torque measurement according to the principle of torsion angle measuring torque.Using ANSYS,a software of the finite element analysis,the paper studied the characteristics of the changing magnetic field under the condition of static and dynamic states.Basis on the distribution principle of the magnetic flux density, the paper studied the influence of the changing magnetic air gap and magnetic shoe to magnetic circuit.On this base,the model sensor had been developed according to the design principle of the sensor.Signal measurement of the model sensor was analysed on the platform of drive system used the the signal sampling and processing module of the Labview.The results preliminary showed that the ring-ball-gird modulated the induced potential periodically,and verified the principle of the sensor.The paper provides a scientific reference for the further research on the structural design of the sensor and lay a foundation for dynamic measuring of torque of mechanical axes under the extreme working conditions.