Spur
gears have teeth with leading edges cut parallel to the axis of rotation.
These straight-cut gears are the simplest type of gear
and work properly only when meshed with parallel axles. The hand-driven
gear that meshes with the fork gear in most turntables, returns and
arcs is a good example. The rate of rotation for the smaller fork gear
is greater than the larger hand-driven gear that turns it, so the apple
rotates faster than the hand-driven gear. Divide the number of teeth
on the hand-driven gear by the number of teeth on the fork gear and
you will know how many times the apple will rotate for every complete
turn of the crank. Multiple spur gears were employed by many designers
of parers and often proved a very aesthetic appearance (above). The hand-driven
and fork gear of the Parker is pictured below.
Spur
gears have teeth with leading edges cut parallel to the axis of rotation.
These straight-cut gears are the simplest type of gear
and work properly only when meshed with parallel axles. The hand-driven
gear that meshes with the fork gear in most turntables, returns and
arcs is a good example. The rate of rotation for the smaller fork gear
is greater than the larger hand-driven gear that turns it, so the apple
rotates faster than the hand-driven gear. Divide the number of teeth
on the hand-driven gear by the number of teeth on the fork gear and
you will know how many times the apple will rotate for every complete
turn of the crank. Multiple spur gears were employed by many designers
of parers and often proved a very aesthetic appearance (above). The hand-driven
and fork gear of the Parker is pictured below.