Research On High Torque Magnetorheological Clutch Based On Squeeze-shear Mode

Magnetorheological fluid is a kind of intelligent material with quick response,reversible reaction process,and easy control.It has been widely used in the research of mechanical transmission system.The traditional magnetorheological clutch is mainly designed based on the shear mode,relying on the magnetorheological fluid to shear the yield stress to transmit torque.Due to the small transmission torque and large size,it cannot meet the industrial needs.Therefore,according to the squeezing enhancement effect of magnetorheological fluid,the magnetized particles in magnetorheological fluid can form a more stable columnar/body-centered cubic structure under extrusion,and the macroscopic performance is the mechanical characteristics of yield stress enhancement and a new type of magnetorheological clutch based on squeeze-shear working mode(referred to as squeeze-shear type magnetorheological clutch)is designed to improve the torque transmission capacity of magnetorheological clutch.In this paper,a series of studies are carried out through the structural design,numerical simulation,torque model,and performance test of the squeeze-shear magnetorheological clutch.The main contents of the work are as follows:(1)The composition,performance,influencing factors and magnetorheological effect mechanism of magnetorheological fluid are introduced.According to the working mode of the magnetorheological application device,a new type of squeeze-shear magnetorheological clutch is designed,and its working principle and characteristics are introduced;based on the theory of electromagnetism,the magnetic circuit of the magnetorheological clutch is designed The material of the magnetic circuit,the structural dimensions of each part of the magnetic circuit and the exciting coil that meet the requirements are determined,and the main parts dimensions of the magnetorheological fluid clutch are determined.(2)Using ANSYS/Multiphysics to simulate the two-dimensional and three-dimensional static magnetic field distribution of the magnetic circuit part of the squeeze-shear magnetorheological clutch,the magnetic induction intensity distribution map of the magnetic circuit part in the squeeze-shear magnetorheological clutch is obtained.The overall magnetic field distribution law is analyzed;by making an observation path along the radial direction in the middle of the magnetorheological fluid working area,the magnetic induction intensity distribution map inside the magnetorheological fluid is obtained,and the distribution law of the magnetic induction intensity and path is analyzed.(3)Based on the Herschel-Bulkley model,a torque transmission mechanical model of the squeeze-shear magnetorheological clutch only in shear mode is established;based on the yield stress constitutive of the magnetorheological fluid in squeeze-shear mode equations are used to derive the torque transmission mechanical model of the new squeeze-shear magnetorheological clutch.(4)An experimental test platform for the squeeze-shear magnetorheological clutch was established,and the static output characteristics and dynamic response characteristics of the squeeze-shear magnetorheological clutch were experimentally studied.Through the experimental study of static output characteristics,the effects of current,speed,squeezing stress and initial gap on the torque of the magnetorheological clutch were obtained;through the study of dynamic response characteristics,the instantaneous current,speed and initial gap were obtained Torque response time relationship;compares the experimental and theoretical results,and analyzes the cause of the error.The results show that the squeeze-shear magnetorheological clutch exhibits better mechanical properties in torque transmission capability and dynamic response time than the traditional magnetorheological clutch.