Motor speed-based anti-pinch control apparatus and method

摘要

The apparatus and method includes a panel movable between at least two positions. An electric motor has a rotating armature. A multiple pole magnet is mounted on the armature. A sensor detects the passage of each magnet pole and generates an output signal. A control measures time periods between each pole passage. An average time period is computed over a predetermined number of time periods. The difference between average time periods is computed and compared with a threshold difference to determine if an obstacle is present in the path of movement of the panel. Transient counts are accumulated for increasing average time periods over a number of time period samples as a measurement of the force exerted on an obstacle by the panel to detect an obstacle.