Linear Pneumatic Cylinder Assembly with Reduced Air Consumption

The method of adding expansion work to pneumatic actuators is studied for classical linear cylinders. The operating principle of new cylinder assemblies is presented. A first simulation set illustrates the performance of the new assembly and tries to define the parameters of a single cylinder which produces the same mechanical performance. Acceleration, speed and reached position within a given time are the conditions for the comparison. Then, the air consumption of both compared systems is calculated. With an experimental set-up, a parasitic effect is observed, which consists of a pre-expansion transient due to parasitic dead volumes related to the tubing and internal volumes of the valves. A second assembly is realized with larger volumetry in order to observe the dependency of the parasitic effect from the size of the cylinders. For the control, a system with simpler control valves is also studied. nbsp;