How Does an Electric Car Window Work?
3 Answers
The working principle of an electric car window is as follows: an electric motor drives the rotation of the gear through the rocker arm handle to lift the window. The electric window system consists of a lift control switch, motor, lifter, and relay. The motor used is a bidirectional permanent magnet motor, which achieves the window's lifting and lowering function by controlling the direction of the current, causing the motor to rotate forward and backward. Installation locations of the electric car window system control switches: 1. The master switch is installed on the dashboard or the driver's side door armrest for easy operation by the driver, allowing the driver to control the lifting and lowering of each window; 2. Individual switches are installed on each passenger's door, operated by the passengers.
I've been driving for several years and am quite familiar with power windows. Simply put, when you press the switch button on the door, electricity is transmitted to the window motor, and the rotation of the motor drives the lifting mechanism. The lifting mechanism usually uses a steel wire or rack to convert rotational motion into up-and-down movement, allowing the glass to go up or down. The motor has two directions—forward and reverse. Pressing the up button makes the motor rotate in one direction, while pressing the down button reverses it. Nowadays, most cars are equipped with an anti-pinch feature. If the glass encounters resistance while rising, it will automatically stop or retract slightly to prevent pinching hands or pets. There’s also a convenient one-touch function where a single press can raise or lower the window all the way without holding the button. If the window stops working, it could be due to a burnt-out motor or a stuck track.
The power window system is quite ingenious, primarily driven by an electric motor. The motor is fixed inside the door, with its force amplified by reduction gears, which then drives the lifting arm to pull the glass along the guide rail. The switch button acts as the control center—pressing it completes the circuit, allowing current to activate the motor. The control module interprets the duration of the button signal; for instance, a short press triggers one-touch operation, while a long press enables normal control. To prevent pinching injuries, the system incorporates pressure sensors or current monitors that instantly reverse the motor if resistance exceeds a preset threshold. Additional safety features include a master control lock on the driver's side, which disables operation of other door windows when engaged. In case of malfunctions, such as slowed movement or unusual noises, potential causes could be insufficient lubrication of the guide rails or worn motor brushes. Regular maintenance, including cleaning dust from the tracks, is crucial.
