24-08-2013, 03:02 PM
Basic Pneumatic Circuitry
Basic Pneumatic .pptx (Size: 1.4 MB / Downloads: 19)
Introduction
This module shows the methods of application of pneumatic valves and components for control and automation
The methods of pure pneumatic sequential control are confined to simple examples
The majority of modern systems are controlled electronically and is the subject of electro-pneumatic modules
Symbols
The standard for fluid power symbols is ISO 1219-1. This is a set of basic shapes and rules for the construction of fluid power symbols
Cylinders can be drawn to show their extreme or intermediate positions of stroke and any length above their width
Valves show all states in the one symbol. The prevailing state is shown with the port connections
Other components are single state symbols
Symbols double acting actuators
Double acting, non-cushioned
Double acting, adjustable cushions
Double acting, through rod, adjustable cushions
Double acting, magnetic, adjustable cushions
Double acting, rodless, magnetic, adjustable cushions
Symbols valves
This example is for a 5/2 valve
This has 5 main ports and 2 states
When the valve is operated at the 14 end port 1 is connected to port 4 (also port 2 is connected to port 3)
When reset to the normal state at the 12 end port 1 is connected to port 2 (also port 4 is connected to port 5)
Component identification
The ISO suggested component numbering system is suited for large circuits and those drawn on several pages
For this presentation a simple code is used
For cylinders: A,B,C etc.
For associated feedback valves: alpha-numeric code ‘a0’ for proof of instroke, ‘a1’ for proof of outstroke
For cylinder B: b0 and b1
2/2 Valve actuator control
The button marked IN is pushed to operate the valve
Air escapes and the piston rod moves to the instroked position
The push button must be held operated until the piston rod is fully in
Atmospheric air will be drawn in to the front of the cylinder through the vent port