摘要 |
An antipinch circuit prevents the motor driven closure of an automotive window if a soft obstacle is compressed between the window and the top of the door frame, and the window is opened in response to the sensing of the obstacle. The circuit measures the motor torque (by measuring motor current) and the motor shaft speed (by measuring motor back EMF). The torque and motor speed are compared to "signatures" of these values in the case of the window closing normally against the top of the door frame, or against an obstacle, and either stopping or reversing the motor rotation accordingly.
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