Cubitt Patent SailsYour model is disabled. For more details go to Edit properties3D Model
Diagrammatic model by Cliff Featherston.
The sails of a windmill need to rotate at a constant pace, so the angle of the shutter blades that catch the wind must be constantly adjusted to suit the wind’s speed.
In 1807 Sir William Cubitt invented a mechanism that allows the shutters to be adjusted whilst the sails are still rotating. In this model the wind shaft has been cut away to show how a rod passing through its centre transfers the movement of the adjustment mechanism at the rear of the cap to the shutter control linkage mounted on the sails.