Machines - definition & concept

The moment you think about Mechanical Engineering the picture of some kind of a machine emerges in your mind, be it your own bicycle, your mother’s sewing machine or a washing machine or your father’s bike or a car. These are all machines.

Let’s try to find out what a machine is! If you get hold of a dictionary and see the definition of a machine you would find the following definitions in general:

•  A machine is a device consisting of fixed and moving parts that modifies mechanical energy and transmits it in a more useful form
• An assembly of interconnected components arranged to transmit or modify force in order to perform useful work

Machines can be broadly divided into two major categories  :   

1.  Simple Machines  
2. Complex Machines

Basic Simple machines are: 

1. An Incline: Enables us to push a heavy load to the desired height in absence of a Crane

2. Wedge: Enables us to split an object into two or create a gap between two bodies.

WEDGE

3. A Lever: A rigid bar enables us to lift or move heavy load with small effort.

Simple LEVER

4. Screw Thread: Enables conversion of  rotational movement to linear movement.

SCREW-THREADS

5. Wheel an Axle: combination of a disc (wheel) & rod (Axle) for obtaining easy motion.

WHEEL & AXLE

6. Pulley: A  Grooved Wheel, fitted on a Pin, enabling us to lift heavy loads with small effort.

SIMPLE PULLEY