Definition

1. Noun:
   • An electrical device that periodically reverses the direction of an electric current: A commutator is a rotary switch used in certain types of electric motors and generators. Its primary function is to reverse the direction of current flow in the motor's windings, which is essential for converting alternating current (AC) to direct current (DC) or for maintaining continuous rotation in a DC motor.

Usage Examples

• Noun:
  • The DC motor's rotation depends on the precise action of its commutator.
  • A common point of wear in older motors is the contact between the commutator and the carbon brushes.

Advanced Usage

• Commutator segments: The copper bars on the rotating part of the commutator, which are insulated from each other.
  • The number of commutator segments corresponds to the number of armature coils.
• Commutator ripple: The small voltage variation present in the DC output of a generator due to the action of the commutator.
  • Filter circuits are used to smooth out the commutator ripple.

Variants and Related Words

• Commutate (verb): To reverse the direction of (an electric current) periodically.
  • The circuit is designed to commutate the current at high speed.
• Commutatorless (adj): Describing a motor (like a brushless DC motor) that operates without a mechanical commutator.
  • Commutatorless motors are often more reliable and require less maintenance.

Synonyms

• Current reverser: A descriptive term for a device that reverses current direction.
• Rotary switch: A general term for a switch that operates by rotation, which describes the commutator's mechanical function.

Related Phrases and Technical Terms

• Commutator and brush assembly: The critical pair of components in traditional DC machines where the brushes supply current to the rotating commutator.
  • The mechanic inspected the commutator and brush assembly for signs of excessive sparking.
• Commutator bar: Another term for a commutator segment.
  • A damaged commutator bar can cause uneven motor operation.

Noun

1. switch for reversing the direction of an electric current