Mumbai University > MECH > Sem 5 > Theory Of Machines 2

Marks: 5 M

Year: Dec 2014

Controlling Force Diagram for spring –controlled Governors

The controlling force diagram for the spring controlled governors is a straight line as shown in fig. We know that controlling force,

$F_c=m.\omega^2.r$ or $F_c/r=m.\omega^2$ The following points, for the stability of spring-controlled governors, may be noted:

1. for the governor to be stable. The controlling force $F_c$ must increase as the radius of rotation (r) increases. i.e. $F_c/r$ must increase as r increases. Hence the controlling force line AB when produced must intersect the controlling force axis below the origin. As shown in fig.

   The relation between the controlling force (Fc) and the radius of rotation (r) for the stability of spring controlled governors is given by the following equation,

   $F_c= (a.r)-b ------------ (i)$

   Where a and b are constants.