com·​mu·​ta·​tor | \ ˈkäm-yə-ˌtā-tər How to pronounce commutator (audio) , -yü- \

Definition of commutator

1 : a series of bars or segments connected to the armature coils (see armature sense 2b)of a generator or motor so that rotation of the armature will in conjunction with a set of fixed brushes (see brush entry 2 sense 3) convert alternating current into direct current

Note: In a generator, a commutator results in an output of direct current. In a motor, the commutator converts incoming alternating current into direct current before using it to generate motion.

2 : an element of a mathematical group that when used to multiply the product of two given elements either on the right side or on the left side but not necessarily on both sides yields the product of the two given elements in reverse order

Examples of commutator in a Sentence

Recent Examples on the Web Before Tesla, inventors had always designed electric motors so that the magnetic field of the stator was kept constant and the magnetic field in the rotor was changed by means of a commutator. National Geographic, "Edison and Tesla's cutthroat 'Current War' ushered in the electric age," 27 Sep. 2019 While watching how a DC motor sparked during a demonstration in his physics class, Tesla suggested that the commutator (the rotating switch feeding electricity to the rotor in the motor) should be eliminated. National Geographic, "Edison and Tesla's cutthroat 'Current War' ushered in the electric age," 27 Sep. 2019 Friction and electrical arcing at the commutator means the brushes must be replaced regularly. The Economist, "Do electric cars dream of software fixes?," 22 Apr. 2018 Instead of brushes and a commutator, a small circuit board coordinates the energy delivery to the windings. Doug Mahoney, Popular Mechanics, "What's So Great About Brushless Motor Power Tools?," 12 Jan. 2018 In a motor using direct current, which comes from a battery, the switching is done with a commutator, a type of mechanical switch. The Economist, "Let’s twist againAs electric motors improve, more things are being electrified," 14 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'commutator.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of commutator

1880, in the meaning defined at sense 1

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The first known use of commutator was in 1880

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Cite this Entry

“Commutator.” Dictionary, Merriam-Webster, Accessed 22 Apr. 2021.

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