Year 10 - Pneumatics
Introduction to Pneumatics
Have you ever used a hand-pump to inflate a bicycle tyre? It can be hard work. The pump takes in air from the atmosphere and compresses it into the tyre. The energy that you use to work the pump is stored in the compressed air. If you release the air from the tyre, it comes out with a rush and a hiss, and escapes into the atmosphere.
Pneumatics provides a way of using the energy that is stored in compressed air, to do useful work.
In pneumatics a compressor is used to provide a supply of compressed air. A compressor uses an electric motor to drive a pump that compresses air into a strong tank called a reservoir. the energy stored in the compressed air can be converted into force and movement, by a pneumatic cylinder.
The compressed air is released, in a controlled way, where it pushes a piston. Pneumatic cylinders are very useful for providing linear or reciprocating movement:
linear - movement in one direction in a straight line;
reciprocating - movement backwards and forwards in a straight line.
Pneumatic systems are very common and are used in many ways such as:
industrial tools such as jack hammers and nail guns;
vehicle doors such as buses and trains;
When you are building and using pneumatic systems, remember that you are dealing with compressed air and with components that are capable of exerting large forces.
1. Never blow compressed air at anyone.
2. Don't turn on the main air supply until the circuit is completely connected up as disconnected pipes can whip round and cause injury.
3. If you notice air leaking from joints or components, turn off the main air supply at once.
4. Always turn off the main air supply before you try to alter a circuit.
5. Keep your fingers clear of moving parts such as piston rods.
6. Wear safety glasses when you are building and operating pneumatic circuits.
We build a number of different pneumatic circuits in class. At all times we should try to use the red pipes for connections between the manifold and port 1 of all valves - we call this 'live air'. Blue pipes are then connected between all other ports and cylinders. This colour co-ordination helps in the process of fault finding.