Gear manufacturing machines are used to cut, form and finish gear teeth. Gear manufacturing machines are used to perform processes such as hobbing, milling, grinding, lapping, and deburring. A gear is a mechanical machine element, which is used to provide positive transmission of power through the meshing of peripherally arranged teeth with a second gear. Gears may be manufactured by casting, stamping, machining or by powder metallurgical processes. In nearly all cases the quality and cost of resulting gears are different. A template method is the most common machining operation for the production of gears and is carried out in a gear cutting machine. The template gear cutting process involves the production of a gear tooth profile by a single point gear cutting tool which is reciprocated and made to follow a guided path by a template. The profile of the template corresponds to the shape of the gear tooth being cut. The template method is employed for spur gear cutting and helical gear cutting. Generally, universal milling machines are used for cutting, forming, and finishing of gears and can act as gear cutting, forming and finishing machines.
Gear manufacturing machines may be manual, semiautomatic, or automatic. Hobbing is a process of generating a gear by means of a cutter, called a hob, that revolves and cuts like a milling cutter. Hobbing is done on a single-purpose gear hobbing machine. There are two basic types of designs available for gear hobbing machines, horizontal work spindles, and vertical work spindles. In gear hobbing, the gear blank is first moved in toward the rotating hob until the proper depth is reached. As soon as the proper depth is reached, the hob cutter is fed across the face of the gear until the gear teeth are complete. Grinding involves cutting of metal, through the use of a multipoint cutting tool, made up of a number of abrasive particles which have been bonded together into a grinding wheel of a desired shape. Gear grinding is used to finish very accurate and hardened gears. However, gear grinding is slow and expensive and is used only on highest quality, hardened gears. Gear manufacturing machines are a very important part of a metal workshop.
Gear manufacturing machines are used in many applications. Examples include their use in cutting, shaping, turning, milling, broaching, grinding, honing, and lapping of gears. Gear manufacturing machines should adhere to various standards specified by the International Standards Organization (ISO).