The Pneumatic Motor with Linear Cylinders

 A pneumatic motor is studied where the pneumatic actuators consist of linear cylinders. This mechanical principle based on the use of a crankshaft and piston rods has the inherent property of being reversible. For this system, the same principle of adding expansion work with an additional volume is applied as it was in the previous chapter for semi-rotary actuators. The mechanical behavior of the crankshaft and piston rod is described, and the following pneumatic displacement and expansion work is simulated. Two different architectures are simulated, namely, first, a system with pistons operating in phase and second, with alternating pistons. The energy efficiency of the new motor is calculated and compared with the efficiency of a system using a single linear cylinder. Further, the principle of realizing the expansion work in the same cylinder as for the displacement work is applied to the motor with linear cylinders. The torque, power and converted work are presented with the simulation results. The study is completed with the presentation of a physical demonstrator system.

Keywords: Adiabatic expansion, Alternating piston-rods, Energy efficiency, Expansion work, In-phase piston rods, Linear cylinders, Pneumatic motor, Torques.