New Dynamic Balancing System Based on Magnetic Interaction and Software Removal of some Perturbations

The purpose of this paper is to present a new type of dynamic balancing system, having a driving solution of the rotating part based on magnetic interactions. the magnetic system also plays the role of an elastic bearing. the structure has some important advantages: an easy to design and build mechanical system; no influence of the environmental factors on the measuring accuracy; low production costs; no direct transmission from the driving motor to the rotor that has to be balanced. in the first part of the article it is presented the technical solution which allows the dynamic balancing evaluation depending on the radial displacement between two disks with permanent magnets, creating a magnetic coupling. it is presented the results obtained on the experimental way, that validated both the numerical simulation as well as the analytic calculation. using a 2d model, the resultant magnetic force was analytically calculated, whose value depends on the misalignment of the balanced part, against the equilibrium position. due to the specific geometry, to validate the 2d analytical calculation model, it was necessary to create a fem model of the magnetic system. a simulation was performed to evaluate the dependence between the radial displacements and the magnetic forces. it was used a 3d simulation software, specific for these kind of problems - the infolytica software. the final results show that there is a similarity between 2d analytical calculation model, 3d simulation and practical measurements. in the second part of the article it is presented a practical application for this type of balancing system, used to build a two plane dynamic balancing machine for card an shafts. it is also shown how it can be eliminated the disturbing unbalance introduced by the clamping system of the balanced part using a software method.