Fig. 2.8: Flow diagram of a BOGE screw compressor, air-cooled
version with fully-adjustable output control | All pneumatic applications must be controlled by some means. They must receive instructions.
In general this is done by press-switches, direction valves and so forth. These control mechanisms are in turn actuated in many different ways, e.g., by mechanical switches, cams, or by hand. Electrical and magnetic switches are also in wide-spread use. The results determined by pneumatic process control systems can be used directly by direction valves or press-switches.
Pneumatics is of great importance for checking flow processes with liquids and gases. It is used for the remote control of valves, slides, and flaps in large industrial installations.
Pneumatics (fluidics) is also used for information processing and logical switching. These logic plans are comparable with integrated electronic circuits. They require much more space, but are characterised by high operating precision in certain applications. If the demands on the logic elements are not too high, fluidics can offer an alternative. |