▸ noun: switch for reversing the direction of an electric current

A commutator is a rotary electrical switch in certain types of electric motors or electrical generators that periodically reverses the current direction between the rotor? and the external circuit. In a motor?, it applies power to the best location on the rotor?, and in a generator, picks off power similarly. As a switch, it has exceptionally long life, considering the number of circuit makes and breaks that occur in normal operation.

A commutator is a common feature of direct current rotating machines. By reversing the current direction in the moving coil of a motor's armature, a steady rotating force (torque?) is produced. Similarly, in a generator, reversing of the coil's connection to the external circuit provides unidirectional (i.e. direct) current to the external circuit. The first commutator-type direct current machine was built by Hippolyte Pixii? in 1832, based on a suggestion by André-Marie Ampère. Wikipedia, Commutator (external link)

See Also

Commutator for Dynamo Electric Machines - 334823
Polar Interchange - Device Design

Created by Dale Pond. Last Modification: Wednesday 06 of March, 2013 08:03:03 MST by Dale Pond. (Version 1)
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