AUTOMATIC TORQUE CALIBRATION FOR ROLLER SHADES

摘要

A motorized roller shade that detects obstacles in its travel that create excess torque by sensing the current draw from a motor and method by which the motor can calibrate itself to detect excess torque. During the roller shade's travel, it will record the instantaneous torque being generated at various points. For example, it will store the greatest value in the shade motor's non-volatile memory as the normal operating torque.

主权项

1. A motorized roller shade comprising:
a roller; a roller shade fabric attached to the roller; a shade motor configured for raising or lowering the roller shade fabric; a controller comprising a motor controller configured for controlling the shade motor and a memory configured for storing over-current threshold values, wherein the controller is configured for:
waiting for said roller shade fabric to be at a lowest limit;after said roller shade fabric is at the lowest limit, waiting for a command to go to an upper limit;capturing an over-current threshold auto calibration value by calculating a sum of a peak value, a fixed minimum value, and a percentage of an average value;when there is (a) no over-current event and (b) the shade effectively reaches the upper limit, storing the over-current threshold auto calibration value; andwhen an over-current event was detected, discarding the over-current threshold auto calibration value and directing the shade motor to stop.