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Introduction
A Governor ;
Controls, maintains, and regulates mean speed of an engine w.r.t varying loads
Increases supply of working fluid if speed of the engine decreases and vice versa
Keeps the mean speed within certain limits
Used mainly in engines of generators not in ordinary vehicles
TYPES OF GOVERNORS
There are two main types of Governors :
Inertia Controlled Governors
Not being used frequently
These governors are more sensitive than the centrifugal governors but it becomes difficult to completely balance the revolving parts
Centrifugal Governors
Centrifugal Governors- Principle
The centrifugal governors are based on the balancing of centrifugal force on the rotating balls by an equal and opposite radial force, known as the controlling force.
Centrifugal Governors- Working
Governor balls or fly balls revolve with a spindle, which is driven by the engine through bevel gears.
The upper ends of the arms are pivoted to the spindle, so that the balls may rise up or fall down as they revolve about the Spring steel vertical axis.
Centrifugal Governors- Working
The sleeve revolves with the spindle but can slide up and down.
The balls and the sleeve rises when the spindle speed increases, and falls when the speed decreases.
The sleeve is connected by a bell crank lever to a throttle valve.
Centrifugal Governors- Working
The supply of the working fluid decreases when the sleeve rises and increases when it falls. When the load on the engine increases, the engine and the governor speed decreases.
This results in Rotating the decrease of centrifugal force on the balls. Hence weight the balls move inwards and the sleeve moves down- wards.
Centrifugal Governors- Working
The downward movement of the sleeve operates a throttle to increase the supply of working fluid and thus the engine speed is increased.