Machine element refers to an elementary component of a
machine. These elements consist of three basic types:
- structural components such as frame members, bearings, axles, splines, fasteners, seals, and lubricants,
- mechanisms that control movement in various ways such as gear trains, belt or chain drives, linkages, cam and follower systems, including brakes and clutches, and
- control components such as buttons, switches, indicators, sensors, actuators and computer controllers.