Cam-wheel raising three hammers
Inked study: a wheel lifts three hammers striking a tooth, with the blow directed off pole n.
The inked figure (f. 92v) shows a wheel that raises three large hammers by means of a peg-studded drum, with a weight hanging on a cord and paired endless-screws sketched below. Leonardo's note explains that when the tooth f is struck by the hammer r, all the force discharges upon the pole n, and advises placing a resistant body at m so the hammer comes to rest like a wedge without loading the pole. A boxed element within the figure is marked 'immovable' to identify the fixed anchoring point.
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Wheel and drum lifting three hammers
A wheel raises three large hammers through a peg-studded drum, the tooth f being driven by the hammer r. A weight hangs from a cord at the right and paired endless-screws are drawn in the lower register.
Directing the blow away from pole n
Leonardo observes that when the tooth f is struck by the hammer r, all its force and effort is discharged on the pole n. He advises fixing a resistant body at m, so that the hammer, striking like a wedge, comes to rest supported and does not burden the pole.
Fixed abutment marked 'immovable'
A boxed element inside the figure is labelled inmobile ('immovable'), naming the fixed part of the mechanism against which the moving members act.