Constant current

Direct current

The DC motors used in the actuators that require a large range of speed regulation, high accuracy of maintaining the speed of rotation of the actuator, the speed control up from the nominal.

How DC motors

The work of the electric DC motor is based on the phenomenon of electromagnetic induction. Of fundamentals of electrical engineering it is known that the current-carrying conductor placed in a magnetic field, a force determined by the left-hand rule:

F = BIL,

where I is the current flowing through the conductor In the magnetic field; L — length of the conductor.

When crossing a conductor of magnetic lines of force of the machine it is induced electromotive force, which is relative to the current in the conductor is directed against him, which is why it is called a reverse or opposing (anti-E. D. C). Electric power in the engine is converted into mechanical and partly spent on heating of the conductor.

In terms of electric DC motors consist of armature and inductor separated by an air gap.

The inductor of the DC motor is used to create a stationary magnetic field of the machine and consists of a frame, main and additional poles. Base is for mounting the main and additional poles and a is an element of the magnetic circuit of the machine. On the main poles located winding intended to generate a magnetic field of the machine plus the poles - a special winding is used for improving commutation.

The armature of a DC motor consists of a magnetic system assembled from individual sheets, the working windings laid in the slots, and a commutator is used to supply to the operating coil ostanovochka.

The collector is a cylinder mounted on a shaft of the engine and elected from isolated from other copper plates. On the manifold there is a ledge-end of the line, to which are soldered the ends of the sections of armature winding. Eat current collector is carried out with the help of brushes providing sliding contact with the collector. Brushes fixed to the brush holders, which hold them in position and provide the necessary touch of brushes on the commutator. Brushes and brush holders mounted on a traverse associated with the motor housing.