What is the working principle of the pneumatic inner swing door of large passenger cars? It is better to have drawings.

The pneumatic rotating mechanism of the car door takes compressed air as the power source, and the air source is controlled by the electromagnetic valve to push the cylinder piston to do reciprocating linear motion. The piston rod converts the linear motion into rotary motion through the action of the screw shaft and the screw sleeve, which drives the car door shaft to rotate, so that the car door can move in parallel, thus realizing the opening and closing of the car door. After the door is closed, under the action of the cylinder piston, the door rises with the door shaft for a certain stroke, so that the wedges at the edge of the door frame are combined to realize the self-locking of the door. In the process of closing the door, if you encounter obstacles (such as people or things being caught), the anti-pinch travel switch will automatically open the door to realize the anti-pinch function. The opening and closing of the car door is realized by a two-position five-way solenoid valve that is instantly energized. The opening and closing speed of the car door can be controlled by adjusting the intake (exhaust) air volume of the air inlet (exhaust). In an emergency, the emergency valve can cut off the air supply and open the door.