ABSTRACT
Gearing and geared transmissions drive the machines of modern industry. The art and science of gearing have their roots before the Common Era. Yet many engineers and researchers continue to delve into the areas where improvements are necessary, seeking to quantify, establish, and codify methods to make gears meet the ever-widening needs of advancing technology. Depending on a particular application, gearings have to meet certain additional requirements, that is, high accuracy of the transmission of rotation, high power density, and so forth. The earliest account of gears comes from ancient Chinese and Greek literature. The mechanical advantage of gears was also used for ship anchor hoists and catapult pretensioning. Gears were also used in wind and water wheel machinery for decreasing or increasing the provided rotational speed for application to pumps and other powered machines. An early gear arrangement was used to power textile machinery.
