MY
KNOWLEDGE ABOUT MECHANISMS
What
are simple machines?
A
simple machine is a mechanical device that
changes the direction or magnitude of a force.
In
general, they can be defined as the simplest mechanisms that use
mechanical advantage to multiply force.
Usually
the term refers to the 6 classical simple machines:
-Lever:
is
a machine consisting of a beam
or rigid rod pivoted at a fixed hinge, or fulcrum.
A lever is a rigid body capable of rotating on a point on itself. A
lever amplifies an input force to provide a greater output force,
which provide leverage.
-Wheel
and axle: consists
of a wheel
attached to a smaller axle
so that these 2 parts rotate together in which a force is transferred
from one to another.
-Pulley:
is
a wheel
on an axle that is designed to support movement and change of
direction
of a taught cable, rope or belt along its circumference.
-Inclined
plane: is
a flat supporting surface tilted at an angle. Used
to move heavy loads over vertical obstacles.
-Wedge:
a
piece of hard material with
two principal faces.
-Screw:
type
of fastener, is an inclined
plane
wrapped around a nail.
USES
OF SIMPLE MACHINES IN OUR DAILY LIFE:
We
use machines every day. Machines help our lives get easier.
The
simple machine that I use the most, in my daily life, is the wheel
and axle. I use it to open de doors, to ride my bike etc.
They
help us to use smaller force to do hard and complex jobs.
TRANSMISSION
OF MOVEMENT
All
mechanical systems have mechanisms which transform an input into an output motion. They make something easier to do.
Some mechanisms change one type of motion into another.
Types of motion:
-Linear motion: moving one way in a straight line. Example: a moving car.
-Reciprocating motion: moving backwards and forwards in a straight line. Example: the up and down motion of a yo-yo.
-Oscillating motion: moving backwards and forwards in an arc. Example: a swing.
-Rotary motion: moving in a circle. Example: a wheel.
MECHANISMS
A mechanism is a simply device designed to transform input forces and movement into a set of output forces and the movement. The mechanisms most commonly used in mechanical systems are levers, linkages, cams, gears and pulleys.
TYPES OF MECHANISMS:
-Mechanical linkage: is an assembly of bodies connected to manage forces and movement. The link is considered to be rigid.
-Cam: rotating piece in a mechanical linkage used in tranforming rotary motion into linear motion or vice versa.
It has 2 main parts: the cam and the follower.
Cams come in many different shapes and sizes. The follower rests on the cam and follows its shape. It may have a small wheel to reduce friction. The follower moves up and down as the cam turns. Cam shapes: circular, pear, snail, four-lobed cam...
-Gears: toothed wheels that interlock. A gear train is where 2 or more gears are linked together. Gears can change the type of motion or the direction of motion. Example: worm drive and worm wheel, bevel gears, rack and pinion...
Examples of them in our daily life:
-Rack and pinion gears are often used on railways.
-Worm drives are used for tightening guitar strings.
MINDMAP:
https://www.mindomo.com/mindmap/b8aaea4a849f4863a3a7fe078e4c0d6d
PERSONAL INTEREST:
I love playing the guitar. The guitar is my favourite instrument, when I can I always play it because I love music. One mechanism, helps me to tighten the guitar, which is called the worm drive and it's a type of gear.
SOURCES OF INFORMATION:
https://www.google.de/search?q=guitar&biw=1024&bih=613&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiW_u3415nQAhWQ2YMKHcQOCAIQ_AUIBigB#tbm=isch&q=worm+gear+guitar
https://en.wikipedia.org/wiki/Simple_machine
http://aulavirtual.caib.es/c07006305/pluginfile.php/9582/mod_resource/content/1/SCAN-348.pdf
https://en.wikipedia.org/wiki/Mechanism_(engineering)
All the photos: Google Images
