Draw
The reliability of the modern lever escapement depends upon draw; the pallets are angled so that the escape wheel must recoil a small amount during the unlocking. The draw holds the lever against the banking during the detached portion of the operating cycle. Draw angle is typically about 15 degrees to the radial.
Early lever escapements lacked draw (indeed some makers considered it injurious as a cause of extra friction in unlocking); as a result a jolt could result in the escapement unlocking.
Read more about this topic: Lever Escapement
Famous quotes containing the word draw:
“I must have the gentleman to haul and draw with the mariner, and the mariner with the gentleman ... I would know him, that would refuse to set his hand to a rope, but I know there is not any such here.”
—Francis, Sir Drake (1540–1596)
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—Ralph Waldo Emerson (1803–1882)
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—G.C. (Georg Christoph)