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Centrifugal Governor

Centrifugal Governor

1centrifugal governor

1centrifugal governor

The Centrifugal Governor was invented by James Watt. It is used to control and regulate the speed of an engine by increasing or deceasing the amount of fuel allowed into the cylinders.

Why the Centrifugal Governor was invented

This mechanism was crucial to the industrial revolution – most of the textile, coal mining, tableware, steel mills and many other industries that were flourishing at the time required a stable engine speed from their steam engines to run effectively and efficiently. For example, if you had a large factory that had many weaving machines that produced lengths of woven cotton to the tailors, with each machine powered by a series of belts by a steam engine, you would need all of your weaving machines to run at a constant speed, otherwise the material produced would have irregular weaves, be substandard and not sell-able.

As soon as this governor was introduced it was received and incorporated by all industries almost immediately. In fact it has been used ever since, it can still be found in modern car engines, jet engines and many other rotating machines. On modern propellers the centrifugal governors senses shaft RPM and adjusts the pitch of the blade to vary the torque load on the engine.

Centrifugal Governor & How it works

The centrifugal governor has various components inside it that allow it to keep the speed of an engine stable, below are the parts of the centrifugal governor –

2centrifugal governor parts

2centrifugal governor parts

The parts shown in the image are as follows –

  • The sliding collar: this can move up and down on the main shaft
  • 3 bearings: these allow the gold parts to open in a scissor-like motion
  •  main shaft: this is the main shaft upon which everything else rests
  •  idle speed plate:this stops the engine going to slow, if this plate was not here the centrifugal governor could cut the fuel supply off from the engine
  • weighted balls: these rise under centrifugal motion as the whole system begins to rotate
  • Pulley to engine: there is a belt attached to this pulley which goes directly to the engine, therefore when the engine speeds up or slows down, the centrifugal governor follows suit

 

The governor can move in two directions, rotary motion and up and down –

centrifugal governor rotary

centrifugal governor rotary

 

centrifugal governor up&down

centrifugal governor up&down

Centrifugal Governor Steam Engine & Animation

This single invention has changed all our lives for the better in many ways, from transport to manufacturing.centrifugal-governor-steam-engine
Below is a video showing a beautiful little steam engine kit, The Wilesco 10 which has a centrifugal governor restricting the flow of steam into the engine –

The video below shows how the centrifugal governor functions in more detail –