Dynamics Of The Field Linear-modulated Magnetic Gear With Intersecting Axes

The linear magnetic modulating gear with adjustable magnet also has the advantages of high utilization rate of permanent magnet and high torque density in addition to the advantages of traditional magnetic gears,such as no contact,no wear,no lubrication and overload protection,etc.and the gear has a good application prospect in medicine,chemical industry,vehicles,food and other fields.Based on the principle of magnetic field modulation,Ansoft Maxwell,an electromagnetic simulation software,was used to conduct finite element analysis of the transmission system.The vector distribution of magnetic flux density of the mechanism was obtained,and the magnetic coupling stiffness of the transmission system was calculated.Based on the dynamic hypothesis,the dynamic model and differential equations of the magnetic gear transmission system with rectilinear intersecting axis of the magnet are established,and the modal analysis of the system is carried out,and three torsion modes and three transverse vibration modes are obtained.The influence of typical parameters of the transmission system on the modal frequency of the system is discussed.The forced vibration differential equations of the axial magnetic gear transmission system was established.The response formula was deduced when incentives frequency in input torque ripple and torque ripple output close to the system each natural frequency of system separately.The rule of the response was analysed when the system resonance occurring,When resonance occurs,only corresponding resonance displacement modal frequency corresponding to the degrees of freedom is large,while other displacement is relatively small.The parametric vibration differential equations of the axial magnetic gear transmission system was established.Using the multi-scale method,the formula of main resonance response was deduced when external excitation frequency close to the system natural frequency,and the formula of combination resonance response was also deduced when external excitation frequency close to the combination of the natural system frequency and magnetic coupling stiffness of meshing frequency.The response law of the primary resonance and combination resonance was analyzed.The conclusion was obtained that the dominant frequency is always the system natural frequency when whether the primary resonance or the combination resonance occurs.The modal experiment platform of the physical prototype was built.The natural frequency test of the prototype was completed by debugging the physical prototype of the transmission system of the adjustable magnet.The rationality of the theoretical calculation was verified by comparing the experimental test results with the analytical calculation results.