Commutator: Construction, and Its Applications

The commutator can be defined as is an electrical rotating switch in particular type of generators as well as motors. This is mainly used to overturn the direction of current among the external circuit & rotor. It comprises a cylinder with numerous metal contact segments lying on the revolving armature of the machine. The brushes or electrical contacts are made with a carbon press material next to the commutator, designing sliding contact by consecutive segments of the commutator while it revolves. The armature windings are allied to the segments of the commutator.

The applications of commutators include DC (direct current) machines like DC generators, numerous DC motors, as well as universal motors. In a DC motor, the commutator provides electric current to the windings. By changing the direction of current within the revolving windings every half turn, a torque (steady revolving force) will be produced.

Commutator Construction and Working

The construction and working of a commutator are, a commutator can be built with a set of contact bars that are set toward the revolving shaft of a DC machine, and allied to the armature windings. When the shaft turns, the commutator will reverse the current flow within a winding. For a particular armature winding, once the shaft has completed the one-half turn, then the winding will be connected so that current supplies through it in the reverse of the first direction.

Commutator
Commutator

In a DC motor, the armature current causes the set magnetic field to use a rotating force, otherwise a torque over the winding for making it revolve. In a DC generator, the mechanical torque can be applied in the direction of the shaft to maintain the armature winding motion via the stationary magnetic field, stimulating a current within the winding. In these two cases, Sometimes, the commutators will reverse the direction of current flow throughout the winding so that the flow of current within the circuit which is external to the machine maintains in only one direction.

Commutator Construction
Commutator Construction

Function of Commutator in DC Machines

The role of the commutator in DC machines is like a reversing switch, and its working in the motor, as well as a generator, is discussed below.

Commutator in DC Machines
Commutator in DC Machines

Commutator in DC Motor

The commutator in case of a DC motor, it reverses the flow of current which is accessible from a DC source at the exact time while the armatures coil crosses the magnetic unbiased axis. This is essential to keep a uni-directional torque. Therefore, the commutator will change the direct current (DC) into alternating current (AC).

Commutator in DC Generator

The commutator in case of a DC generator, the induced e.m.f within the armature coil will change in nature. Consequently, the flow of current in the armature coil will also be changed. This current will be reversed by the commutator at the exact time while the armatures coil crosses the magnetic unbiased axis. So, the load which is external to the generator will get a uni-directional current otherwise DC (direct current).

Slip Ring Commutator

A slip ring commutator is an electro-mechanical device, used to allow the power transmission as well as electrical signals from an immobile to a revolving structure. This can be utilized in any kind of electro-mechanical system that needs revolution while power transmitting. It can recover mechanical act, make simpler system operation & get rid of damage-prone wires hanging from variable joints. A slip ring commutator is a technique of building an electrical connection throughout a rotating assembly. Properly, it is an electric communication device that permits the flow of energy among two electrical rotating elements in a motor.

Slip Ring Commutator Construction

The slip ring commutator construction is, consists of immobile graphite otherwise brush which is known as metal contact which wipes on the exterior diameter of a revolving metal ring.

When the metal ring twists, the flow of electric current otherwise signal is performed through the immobile brush toward the metal ring for making the connection. An extra ring or brush gatherings are stack along with the revolving axis if more than a single electrical circuit is required.

Both the brushes otherwise the rings are motionless, another component will rotate. This easy design has been utilized for decades like a basic method of passing current into a rotating device.

Types of Slip Rings

Slip rings are available in various sizes as well as types. This will allow for infinite turns of the allied object, while a slack-cable cannot be turned many times before it will not pass. The slip rings are classified into three types such as Mercury-wetted, Pancake, and Wireless.

Other Names and Uses of Commutators

Other names of slip ring mainly include rotary electrical contact ring, collector ring, & electrical ring. Based on the application, it can be named as the commutator, but these are fairly different & are particularly used for DC motors as well as generators.

As commutators are sectioned, these are continuous, and the names are not identical. Rotary transformers are frequently used in its place of slip rings in the environments like high-speed, otherwise low-friction.

This can be used to act concurrently in a rotary union by the device, which is normally called as a rotary joint. These rings perform the similar for electrical power as well as a signal that rotary unions perform for fluid media. They are frequently incorporated into rotary unions for transmitting power & data from revolving machinery within conjunction by the media that the revolving union supplies.

Other Names and Uses of Slip Rings

Other names of slip ring mainly include rotary electrical contact ring, collector ring, & electrical ring. Based on the application it can be named as a commutator, but these are fairly different & are particularly used for DC motors as well as generators.

As commutators are sectioned, these are continuous, and the names are not identical. Rotary transformers are frequently used in its place of slip rings in the environments like high-speed, otherwise low-friction. This can be used to act concurrently in a rotary union by the device, which is normally called as a rotary joint. These rings perform the similar for electrical power as well as the signal that rotary unions perform for fluid media. They are frequently incorporated into rotary unions for transmitting power & data from revolving machinery within conjunction by the media that the revolving union supplies.

This can be used to act concurrently in a rotary union by the device, which is normally called as a rotary joint. These rings perform the similar for electrical power as well as a signal that rotary unions perform for fluid media. They are frequently incorporated into rotary unions for transmitting power & data from revolving machinery within conjunction by the media that the revolving union supplies.

Thus, this is all about commutators which are fairly incompetent, & also need periodic preservation like brush substitution. Thus, commutated machines will decline for utilization being restored by AC (alternating current) machines, & now current days brushless DC motors use semiconductor switches. Here is a question for you, what is the working of commutator?



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