US Patent 7679362 Hall-effect pressure switch

A switch includes housing and a magnet that is mounted inside the housing. The magnet generates a magnetic field having magnetic flux. The switch further includes a flux concentration device that is located inside the housing and that selectively moves between first and second positions. An actuator assembly is located inside the housing and selects the first and second positions based on the input. A hall-effect device is located between the magnet and the flux concentration device and conducts a current having a first value when the magnetic flux is less than a predetermined magnetic flux threshold. The hall-effect device conducts current having a second current value when the magnetic flux exceeds the predetermined magnetic flux threshold. The first position communicates a first magnetic flux to the hall-effect device and the second position communicates a second magnetic flux that is different from the first magnetic flux to the hall-effect device.