This mechanism is irreversible but
it gives a massive increase in
torque.
Uses include helicopter winches
Crown and Pinion
This mechanism is reversible
and does result in a change in
torque. However that depends
on which input gear is used.
Uses include hand-drills
Bevel Gears
Uses
include the
millstones in
wind-mills
This mechanism is reversible and can
sometimes change torque. That
depends on the sizes of the input and
output bevel gears.
Linear Mechanisms
Rack and Pinion
This mechanism is
reversible, however
torque is not changed.
Uses include the
steering for cars.
Leadscrew
This mechanism is not
reversible at all, however
there is a huge increase in
torque.
Uses include a car-jack
Reciprocating Mechanisms
Crank and Slider
This mechanism can be reversed and it
works at any angle. Torque is irrelevant.
Uses include the inside of
a car engine where they
work as pistons.
Cam and Follower
This mechanism is not reversible. It
does not work at every angle unless if
a spring is fitted to the follower.
Uses include oil pumps.
Oscillating Mechanisms
Crank and Lever
This mechanism is reversible
and it can work at any angle.
Torque can be changed by
changing the distance between
the lever's fixed pivot and it's
moving pivot.