The vane air motor is a device that can convert the pressure of compressed air into rotational mechanical energy. The most widely used in pneumatic transmission are vane and piston types. It is mainly composed of motor housing, connecting rod, crankshaft, piston, cylinder, valve and so on. The compressed air enters the valve core to make it rotate, and at the same time, the compressed air is fed into the surrounding cylinders in turn by the rotation of the valve core. Due to the expansion of the compressed air in the cylinder, the piston rod and the crankshaft are pushed to rotate. When pushed to the "bottom dead center", the valve spool also moves to the first exhaust position.