Further studies of a variable-ratio transmission
Red-chalk variants of an oval toothed cam meshing a gear
In red chalk and oriented upside down, this page continues the mechanical studies of the preceding folio, as the e-Leo caption notes. Two arrangements are drawn: in each, a spoked or crank wheel drives an oval, almond-shaped toothed cam so that the transmitted ratio varies over a turn. The upper and lower versions differ in the pinion and in the framing that carries the shafts. The chalk is faint and the forms overlap; further untranscribed construction lines are present.
On this page
Oval toothed cam driven by a wheel (upper)
In the upper arrangement a spoked wheel on a horizontal shaft drives an almond-shaped toothed cam set in a rectangular frame. The non-circular cam gives a ratio that changes as it turns.
A ratio that changes over each turn
As on folio 111v, the oval cams make the ratio between the two shafts vary continuously through a revolution instead of remaining constant. The lower arrangement, with a star pinion and crank at the left, is a second variant of the same idea.