Fig. a is the working principle diagram of vane pneumatic motor. When compressed air is input through hole A, it is divided into two paths: one path enters the bottom of the blade through the slots (not shown in the figure) of the sealing covers at both ends of the stator, and pushes the blade out, so that the blade is tightly attached to the inner wall of the stator under the comprehensive action of air pressure thrust and centrifugal force after the rotor rotates. The other compressed air enters the corresponding sealed working space through the hole and acts on the two blades. Due to the unequal extension lengths of the two blades, the torque difference is generated, which makes the blades and the rotor rotate counterclockwise. The gas after doing work is discharged from the hole c on the stator, and the remaining residual gas is discharged through the hole. If the input direction of compressed air is changed (that is, compressed air enters from hole B and is discharged from hole A and hole C), the rotation direction of the rotor can be changed. Fig. b is the working principle diagram of radial piston pneumatic motor. Compressed air enters the distribution valve (also known as the distribution valve) through the air inlet, then enters the cylinder to push the piston and connecting rod assembly to move, and then the crankshaft rotates. When the crankshaft rotates, it drives the distribution valve fixed on the crankshaft to rotate synchronously, so that compressed air enters different cylinders with the change of the angular position of the distribution valve, and then drives each piston to move, and each piston and connecting rod drives the crankshaft to run continuously. At the same time, the cylinder corresponding to the intake cylinder is in the exhaust state.
Fig. c is the working principle diagram of the membrane pneumatic motor. It is actually a thin film cylinder. When it reciprocates, the ratchet wheel rotates through the pawl at the end of the push rod.