Reluctance spring for use with piezoelectric vibration generator in vibration-energy-harvesting-system, has movable, soft-magnetic mass element arranged in air gap and changing total reluctance in magnetic circuit by movement

摘要

The spring has a magnetic field generation element for generating magnetic field and formed by permanent magnets (100), and a core element (102) for guiding the magnetic field and for generating a magnetic circuit, where the core element defines an air gap. A movable, soft-magnetic mass element (104) is arranged in the air gap and changes total reluctance in the magnetic circuit by movements (106). The core element is made from iron, where the spring is made from metal sheets glued with one another or from soft-magnetic powder filled polymer. An independent claim is also included for a vibration generator.