A Transverse-Flux Constant Force Mechanism

A new type of constant force magnet mechanism is presented that relies on the interaction of magnets alone to create a constant force over a prescribed stroke length. It is demonstrated that by using a transverse field path a very uniform radial field along the travel length is created. This can then be used to create a constant force over a long stroke length. The constat force value is shown to be adjustable through the rotation of the stator relative to the translator. The operating principle of the presented transverse-flux constant force mechanism is validated by using 3-D finite element analysis. An experimental prototype is also presented that is being used to demonstrate and validate the working principle. The proof-of principle prototype is calculated to create a 1371 N peak constant force over a 32 mm stroke length. The energy density and peak airgap shear stress of the design are calculated to be 7.3 J/kg and 93 kN/m² respectively.