Pneumatic cylinders systems that uses the power of compressed gas to produce a motive force. This force is responsible for moving the piston (the disc) in the desired direction, whether it is linear or rotary, by pushing the cylinder rod. The functioning of pneumatic cylinders reminds that of syringes, for example. Because they use gas as the main force producing the motion, they are also known as air cylinders.
Pneumatic cylinders tend to be quieter and cleaner than their hydraulic counterparts, and are therefore often preferred by engineers in machine applications as there is no risk of leakage threatening to contaminate the surface they are applied to. They can also be found in forms of rodless cylinders, which are particularly convenient when there is the necessity for great power in a significantly lower space than the one needed for conventional pneumatic cylinders.
Pneumatic cylinders can be controlled via an actuator, which is the component responsible for the motion of a mechanism or system. Actuators work thanks to the combined action of a control signal and a source of energy, which in this case are represented by pneumatic pressure. When the actuator receives the pressure as a signal, it converts its energy into mechanical motion. According to the type of motion actuators cause, they are distinguished in two main types: linear actuators and rotary actuators.
They are used in main engine control systems, in the manufacturing industries (such as opening valves or rotary belts) and in the automotive sector (for example, for breaks and suspensions in cars and trucks).