Gears are about as old as any of the machinery of mankind. The oldest
machine is the potter's wheel. At first time over 3000 years ago
primitive gears first meshed with each other and transmitted rotary
motion. In the fourth century, BC Aristole wrote about wheels using friction between smooth surfaces to transmit motion. The earliest gears were of wooden and had teeth of really engaging pins. The early Greeks made use of metal gears with wedge shaped teeth. The Romans made considerable use of gears in their mills. In middle age stone gears were used in Sweden.
Water wheels were used to convert energy of moving water into energy that would power machines. Wooden gears connected water wheels to machines that would grind wheat and hammer metals.
Importance of clocks
Later metal clock gearing also became important. Clocks and watches were made that showed accurate time. Later mechanical clocks also started in Europe and were invented by monks. The first mechanical clock was made of escapement device and had a set of tooth gearing.
Influence of Bicycles in Gear Evolution
The history of cycling has had an immense influence on the technologies and industries. The story of bicycle starts in 1817 when Baron Won Drais of Baden invented a 'running machine' to help him move more quickly around his forests. Then after there were many changes that took place in improving the make up and usage of bicycles.
Development of chain drive was an added advantage. Leonardo Da Vinci had developed an idea of chain and cog in the fifteenth century. It took years to implement on this idea and make it a practical aspect of bicycle design. Later gear was invented and was an added advantage to the bicycle design.
Gears allowed the cyclist to pedal at a comfortable and efficient rate especially while travelling uphill or downhill. Paul de Vivie of French was a passionate advocate of cycling. He rode his first high wheeler at the age of 28, sold his silk business and started a bike shop.
Industrial Revolution and Gears
Wooden gears were used all over the world by the eighteenth century. They were used in gristmills, textile mills and steel mills. The use of electric motors and steam engines created a considerable need of the gears. Few years later gears were widely used in all parts of the world in a wide number of industries. Gears were also preeminent for scientists who required more accurate clocks and using gears they made clocks with more accuracy, one of them was pendulum clock.
The industrial revolution in Britain in the eighteen-century saw an explosion in the use of metal gearing. A science of gear design and manufacture rapidly developed through the nineteenth century.
Today, the most significant new gear developments are in the area of materials. Modern metallurgy has greatly increased the useful life of industry and automotive gears. Along with this consumer electronics have driven plastic gearing to new levels of lubricant free reliability and quiet operation. Gears are also used in many machines that we use in our homes. The washing machines and electric drills are some of the machines that have gears.