- Shaded-pole motor
A shaded-pole motor is a type of AC single-phase induction motor. As in other
induction motors the rotating part is a squirrel-cage rotor. All single-phase motors require a means of producing a rotating magnetic fieldfor starting. In the shaded-pole type, a part of the face of each field pole carries a copper ring called a shading coil. Currents in this coil delay the phase of magnetic fluxin that part of the pole enough to provide a rotating field. The effect produces only a low starting torquecompared to other classes of single-phase motors.
These motors have only one winding, no capacitor nor starting switch, making them economical and reliable. Because their starting torque is low they are best suited to driving fans or other loads that are easily started. Moreover, they are compatible with
triac-based variable-speed controls, which often are used with fans. They are built in power sizes up to about 1/6 hp or 125 watts output. For larger motors, other designs offer better characteristics.
The first photo is of a common C-frame motor. With the shading coils positioned as shown, this motor will start in a clockwise direction as viewed from the long shaft end. The second photo shows detail of the shading coils.
Wikimedia Foundation. 2010.
Look at other dictionaries:
shaded-pole motor — ˈ ̷ ̷ ̷ ̷ˌ ̷ ̷ noun : a single phase induction motor in small ratings made self starting by flux displacement derived by means of a permanently short circuited, high resistance winding or loop encircling a fraction of the pole pitch or pole piece … Useful english dictionary
shaded-pole motor — Small ac motor designed to start under light loads … Dictionary of automotive terms
Shaded-pole synchronous motor — Shaded pole synchronous motors are a class of AC motor.Like a shaded pole induction motor, they use field coils with additional copper shading coils (see the illustration) to produce a weakly rotating magnetic field. But unlike a shaded pole… … Wikipedia
electric motor — motor (def. 4). [1885 90] * * * Introduction any of a class of devices that convert electrical energy to mechanical energy, usually by employing electromagnetic phenomena. Most electric motors develop their mechanical torque by the… … Universalium
Electric motor — For other kinds of motors, see motor (disambiguation). For a railroad electric engine, see electric locomotive. Various electric motors. A 9 volt PP3 transistor battery is in the center foreground for size comparison. An electric motor converts… … Wikipedia
AC motor — An AC motor is an electric motor that is driven by an alternating current. It consists of two basic parts, an outside stationary stator having coils supplied with AC current to produce a rotating magnetic field, and an inside rotor attached to… … Wikipedia
Brushless DC electric motor — A microprocessor controlled BLDC motor powering a micro remote controlled airplane. This external rotor motor weighs 5 grams, consumes approximately 11 watts (15 millihorsepower) and produces thrust of more than twice the weight of the plane … Wikipedia
Ceiling fan — A ceiling fan is a fan, usually electrically powered, suspended from the ceiling of a room, that uses hub mounted rotating paddles to circulate air. Casablanca Fan Co. ceiling fan from the early 1980s. A ceiling fan rotates much mo … Wikipedia
Rotating magnetic field — A rotating magnetic field is a magnetic field which changes direction at (ideally) a constant angular rate. This is a key principle in the operation of the alternating current motor. In 1882, Nikola Tesla identified the concept of the rotating… … Wikipedia
Phonograph — Turntable redirects here. For other uses, see Turntable (disambiguation). Edison cylinder phonograph ca. 1899 … Wikipedia