| 20100052661 | Detection of the Onset of Switch Actuation via Magnetic Field - A magnet is affixed to a shaft or other pivoting or rotating member of a switch mechanism, on the axis of rotation. The radial position of the resulting magnetic field is monitored. A change in the magnetic field radial position, optionally in excess of a threshold, indicates the onset of switch actuation, prior to operative actuation of the switch mechanism. The radial position of the magnetic field is sensed by a magnetic rotary encoder. The detection of switch actuation onset may be used to remove current from a circuit prior to operative switch actuation. Because the magnet is rigidly affixed to the shaft, there is no lost motion. Because the shaft position and encoder are magnetically coupled, the detection mechanism contains no moving parts and no mechanical linkage or coupling, and its performance does not degrade due to shock, thermal effects, vibration, or wear. | 03-04-2010 |
