Introduction:
The window mechanism is mounted in the car doors. The mechanism ensures the proper opening and closing of the door windows.
The electric and mechanical (hand-operated) window mechanisms work according to the same principle. Instead of turning with a crank, the electric motor’s shaft drives the mechanism.
Below is shown a window mechanism of a BMW 3 series. The door panel is removed (it is mounted here with several screws and clips). The window mechanism itself is barely visible. It is mounted on the inside of the door. The window is also still mounted in it.
There is always a cover mounted on this side of the door. This cover must prevent moisture from entering the interior. Most manufacturers use foil for this. Other manufacturers use metal plates, to which the mechanism is attached. In the car of the above picture, foil is applied. The remnants of the sealant are still present here.
Types of Window Mechanisms:
The image on the right shows a window mechanism with a single guide rail. The window motor pulls on the cable, causing the window mount to move up or down. This type of mechanism is often used at the rear because the door window is usually smaller (and lighter) there than at the front (where a double guide rail is typically used).
Another version is a mechanism with a double guide rail. The cable runs crosswise. This way, the window mounts can both move up or down simultaneously. In this mechanism, too, the window motor drives the cable, which moves the window mounts up or down.
The window mechanism in the image on the right does not use cables. Here, the window motor drives a gear, which in turn moves up or down. The mechanism makes a scissor-like movement, causing the right guide in the guide rail to slide left and right. Due to the scissor movement, the door window will move up or down.
