Left Hand and Right Hand Worm
A right hand helical gear or right hand worm is one in which the teeth twist clockwise as they recede from an observer looking along the axis. The designations, right hand and left hand, are the same as in the long established practice for screw threads, both external and internal. Two external helical gears operating on parallel axes must be of opposite hand. An internal helical gear and its pinion must be of the same hand.
A left hand helical gear or left hand worm is one in which the teeth twist counterclockwise as they recede from an observer looking along the axis.
Read more about this topic: Worm Drive
Famous quotes containing the words left hand, left, hand and/or worm:
“Therefore when thou doest thine alms, do not sound a trumpet before thee, as the hypocrites do in the synagogues and in the streets, that they may have glory of men. Verily I say unto you, they have their reward. But when thou doest alms, let not thy left hand know what thy right hand doeth.”
—Bible: New Testament Jesus, in Matthew, 6:2-3.
From the Sermon on the Mount.
“Sisters define their rivalry in terms of competition for the gold cup of parental love. It is never perceived as a cup which runneth over, rather a finite vessel from which the more one sister drinks, the less is left for the others.”
—Elizabeth Fishel (20th century)
“Another gentleman ... desired to know if I was engaged, or would honour him with my hand [to dance]. So he was pleased to say, though I am sure I know not what honour he could receive from me; but these sort of expressions, I find, are used as words of course, without any distinction of persons, or study of propriety.”
—Frances Burney (1752–1840)
“Fly fishing may be a very pleasant amusement; but angling or float fishing I can only compare to a stick and a string, with a worm at one end and a fool at the other.”
—Samuel Johnson (1709–1784)