| 摘要 |
The instant invention senses shutter blade position indirectly by sensing the position of rotor(s) driving the shutter blade in an electromagnetically driven actuator system. It generally comprehends systems where a plurality of rotors each drive respective blades of a shutter such that the position of each of the rotors is indicative of the position of their respective shutter blades, and combines such systems with non-optical sensors responsive to the rotors which signal the position of the shutter blades based on the position of the rotors. The non-optical sensors used are preferably responsive to the magnetic fields produced by the rotors, and can be advantageously positioned adjacent stator poles associated with the rotors, which stator poles are associated with the open or closed positions of the shutter blades. The sensors are preferably Hall Effect (Hall IC) sensors producing voltages proportionate to and greatest when the pole of a magnet is proximate the Hall Effect sensor. Thus, the system can be arranged with sensors adjacent stator poles associated with a closed blade/shutter configuration, or arranged with sensors adjacent stator poles associated with an open blade/shutter configuration, so that the voltage signal produced is highest/lowest for either a closed/open shutter condition or the opposite. |
