A Pickering governor consists of a spindle and three straight leaf springs (each consisting of a single leaf). These three identical leaf springs are symmetrically placed (i.e. at equal angular intervals) around the spindle. A fly-ball in the form of a weight is attached to each leaf spring at the centre.
(a)
(b)
Fig. 1: Pickering Governor
Working of Pickering Governor
Fig. 1 (a) shows the Pickering governor, when it is at rest. When load on engine decreases, then the speed of governor and hence speed of spindle increases, the weights move outwards due to the action of centrifugal force. It causes the leaf springs to bend outwards, since they rotate about the spindle axis with increasing speed. Refer Fig.1 (b). The sleeve can rise until; it reaches a stopper, whose position can be adjusted. Due to raising sleeve, supply of fuel decreases and speed of governor and hence, engine speed can be reduced till it reaches the desired speed.
Application of Pickering Governor
Pickering Governor is mostly used for driving gramophone to adjust speed of turn-table.
