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:
“Human beings ought not to draw in their antennae at every ungentle touch, like supersensitive insects.”
—E.T.A.W. (Ernst Theodor Amadeus Wilhelm)
“Whether our feet are compressed in iron shoes, our faces hidden with veils and masks; whether yoked with cows to draw the plow through its furrows, or classed with idiots, lunatics and criminals in the laws and constitutions of the State, the principle is the same; for the humiliations of the spirit are as real as the visible badges of servitude.”
—Elizabeth Cady Stanton (1815–1902)
“For my enemy is dead, a man divine as myself is dead,
I look where he lies white-faced and still in the
coffin—I draw near,
Bend down and touch lightly with my lips the white face in the
coffin.”
—Walt Whitman (1819–1892)