What is the principle of car power windows?

The working principle of car power windows is to use a servo motor to drive the glass up and down, replacing the traditional crank handle for raising and lowering the glass, making the operation much easier.

The motor-driven window glass can automatically rise and descend, featuring an anti-pinch function. Power windows allow the driver or passengers to operate the door glass with a simple switch while seated, enhancing convenience and driving safety. This has become the preferred design for windows by major manufacturers.

The anti-pinch window regulator refers to a mechanism where, if a body part or object is detected in the rising area, the glass immediately reverses (lowers) a certain distance and stops to prevent injuring passengers.

From an electrical engineering standpoint, power windows work through a simple DC motor circuit. Pressing the switch completes the circuit, sending 12V from the car's battery to the motor. The motor's polarity reverses when the switch is pressed in the opposite direction, making the window go up or down. Some systems use pulse-width modulation for speed control.