Varying power in an eccentric drive and a two-wheel gear
The lever S a lengthens from S b as wheel S turns; meshed wheels give even movement but uneven power.
Two mechanisms illustrate how driving geometry changes the delivery of power. At the top, an eccentric toothed wheel S drives a lever whose effective arm changes through the cycle, growing from S b to S a as it reaches the line S n, so the power varies continuously. At the foot, two large toothed wheels mesh directly, giving a motion equal in movement but strongly unequal in the power of its source. The centre of the sheet also carries a large, carefully shaded drawing of a cylinder resting on an upright cage of rods, for which the transcription supplies no caption.
On this page
Varying power of the eccentric lever S a
An eccentric wheel S drives a lever whose length varies as it turns: the arm S a has grown from S b, as shown when it reaches the line S n. Because of this, the power varies continuously in the course of the motion.
Two meshed wheels: even movement, uneven power
At the foot, two large toothed wheels mesh directly. This motion will be equal in movement but strongly unequal in the power of its motor.
Cylinder borne on a cage of rods
The centre of the sheet carries a large, carefully shaded drawing of a cylinder resting diagonally across an upright bundle of rods. No caption for this figure is included in the transcription.