rotor(redirected from rotor arm)
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in electricity, machine used to change mechanical energy into electrical energy. It operates on the principle of electromagnetic induction, discovered (1831) by Michael Faraday.
..... Click the link for more information. ; motor, electricmotor, electric,
machine that converts electrical energy into mechanical energy. When an electric current is passed through a wire loop that is in a magnetic field, the loop will rotate and the rotating motion is transmitted to a shaft, providing useful mechanical work.
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in engineering. (1) The rotating part of motors and machines, in which are located the members that receive energy from the working medium (for instance, the rotor in a Wankel engine) or that transmit energy to a working medium (for instance, the rotor in a rotary pump). In motors, the rotor is connected to a driving shaft; in machines, it is connected to a driven shaft. Rotors are made in the shape of drums, disks, or wheels.
(2) The rotating part of, as a rule, an alternating-current machine. It is usually a cylindrical body with grooves that contain the winding.
the rotating part of an electric machine. As a rule, the concept of a rotor refers to alternating-current machines; in direct-current machines, the rotor is called an armature.
The rotor of an induction machine is usually fabricated from electrical sheet steel and has the shape of a cylinder with grooves that contain the winding. Depending on the type of winding used, induction machines are classified as either phase-wound or squirrel-cage machines. A phase-wound rotor has a three-phase winding with the same number of sections as are in the stator. The sections are usually Y-connected, and their terminals are connected to a starting rheostat through collector rings and brushes. The winding of a squirrel-cage rotor consists of metal bars that are short-circuited at each end.
Rotors in synchronous machines are classified as salient-pole and nonsalient-pole rotors. A salient-pole rotor consists of a yoke and of poles attached to the yoke and equipped with field windings. A nonsalient pole rotor is usually fabricated as a unit from a single steel forging. Grooves for field winding are milled into the forging.
REFERENCESKostenko, M. P., and L. M. Piotrovskii. Elektricheskie mashiny, 3rd ed., parts 1–2. Leningrad, 1972–73.
M. I. OZEROV
ii. The portion of a turbine or compressor that spins.
iii. A rotating disc or drum to which a series of blades are attached (e.g., compressor, turbine, turbopump, alternator).
iv. A local air mass rotating about a substantially horizontal axis.