The commutator mainly has hook type, groove type, flat type and other specifications. It is made of imported raw materials and its performance has reached the international advanced level. It is widely used in power tools, household appliances, automobiles, motorcycle motors and other fields; collector rings, carbon brush holders, wiring boards have various specifications and models of products, applications Used in automobile generators, gasoline generators and other fields. The commutator functions as a rectifier, and its function is to make the direction of the current in the armature winding alternate to ensure that the direction of the electromagnetic torque remains unchanged. In the generator, the commutator can make the alternating electric potential in the element into the direct electric potential between the brushes; in the motor, he can make the external direct current into the alternating current in the element, producing a constant direction torque.
The commutator and the brush form a corresponding sliding friction pair in the motor. The influence of the commutator on the performance of the motor mainly depends on the electrical contact behavior when the brush is sliding at a high speed under certain conditions. In addition to transmitting longitudinal current, the commutator also has the task of current commutation in the short-circuit armature coil.
Maintenance of DC motor commutator
(1) Sweep and wipe the surface of the commutator to ensure cleanliness.
(2) Establish a production process for reasonable distribution of motor load to ensure that a good film (also called oxide film) is established on the surface of the commutator. It is found that the surface condition of the commutator is deteriorated and the spark is large. You should consider stopping the machine and sanding the surface with fine sandpaper to re-establish the oxide film.
(3) Check whether the mica groove is clean, the edges and corners of the commutator should be smooth and free of burrs.
(4) Under the condition of ensuring the surface quality of the commutator, it is also necessary to carefully observe and monitor the commutating sparks in daily operation. Under normal circumstances, point and granular sparks (white or slightly blue and yellow) are sparsely and evenly distributed on most of the brushes, which are normal reversing sparks. The noise-like, fireball or splash-like sparks (dark yellow, red or green) are harmful sparks. When a ring-fire spark occurs, the motor should not continue to run.