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1. A cylindrical arrangement of insulated metal bars connected to the coils of a direct-current electric motor or generator, providing a unidirectional current from the generator or a reversal of current into the coils of the motor.
2. Mathematics In a commutative or noncommutative group, an element of the form ghg-1h-1 where g and h are elements of the group. If g and h commute, the commutator is the identity element.


1. (Electronics) a device used to reverse the direction of flow of an electric current
2. (Electrical Engineering) the segmented metal cylinder or disc mounted on the armature shaft of an electric motor, generator, etc, used to make electrical contact with the rotating coils and ensure unidirectional current flow


(ˈkɒm yəˌteɪ tər)

a. a device for reversing the direction of a current.
b. (in a DC motor or generator) a ring or disk assembly that works to change the frequency or direction of current in the armature windings.
2. Math. the element equal to the product of two given elements in a group multiplied on the right by the product of the inverses of the elements.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.commutator - switch for reversing the direction of an electric currentcommutator - switch for reversing the direction of an electric current
electric switch, electrical switch, switch - control consisting of a mechanical or electrical or electronic device for making or breaking or changing the connections in a circuit
References in classic literature ?
Dudley wanted to show me the commutator on the exhaust-box or the windscreen, or something, and he was just bending over when Eustace jumped out from nowhere and pinned him.
The feature of the cutting process while commutator turning is that cutting has an intermittent nature, since the collector consists of alternating copper and insulating plates.
Now assume that [gamma] is not a subset of the contacts of [LAMBDA]', and consider any commutator of [gamma] which is not a contact of [LAMBDA]'.
We show that for one-dimensional problems, it is possible to specify boundary conditions in such a way that the commutator is zero even at domain boundaries.
It's one of the most complicated commutator rings that we've ever seen," said the engineer, who asked not to be named.
This design uses specially formulated graphite that is molded directly into and around the commutator body, producing a secure assembly without solder or adhesives.
We also admitted an assumption about absence of heat flow going between adjoining commutator segments on lateral faces through insulating pads, that is main heat flow goes along vertical axis through commutator segment.
Additionally, AC drive motors have no springs, brushes, commutator or wearable parts thus reducing planned maintenance.
It has a full complement of features that permit use of a mud motor for drilling solid rock -- a wireline commutator for wireline navigation instruments; rotary brake to prevent the mud motor from turning the drill string in reverse; and a large (2.
A disk-like rotary commutator on the end of the drum turns the vacuum on and off for each slat as it rotates into position to receive the web of melt from the die.
Benefitting from increased automotive production and our rising share of the motor commutator market, first quarter 1994 sales of Rogers moldable composite materials were the highest in the past five years.
Individual chapters are provided concerning permanent magnet DC commutator motors, permanent magnet synchronous motors, DC brushless motors, axial flux motors, high power density brushless motors, brushless motors of special construction, and stepping motors.