TYPES OF MECHANICAL MACHINE
Here's a mnemonic
phrase that serves to recall the names of the different types of machine
found in universal mechanics, sent in (9/00) by Barbara D. Marin:
"I Like Playing Soccer With William."
(Inclined plane, Lever, Pulley, Screw,
Wedge, Wheel and axle)
A machine is a contrivance or mechanism by means of which a
force, applied at one part of the machine, is transmitted to another
part, in order to secure mechanical advantage for some particular
purpose. There are basically six types of machine:
The inclined plane
- used for raising a load by means of a smaller applied force.
Mechanical advantage is resisted by some friction.
- involves a load, a fulcrum and an applied force. Often just a uniform bar.
- In simplest form it changes the direction of a force acting along a
cord or rope.
- constructed using the principle of the inclined plane set on a cylindrical
or conical surface. A screw-jack lifts heavy weights. Many
screw-threads are in everyday use.
- a double inclined plane. Mechanical advantage is considerably resisted by
The wheel and axle
- Used to draw water from a well etc. by ropes attached to a large wheel and
to a smaller axle. A differential wheel and axle has two-part axle sizes and
gains considerable mechanical advantage.