MOTOVARIO motor spare parts

1. According to the type of working power supply, it can be divided into DC motors and AC motors.

1) DC motors can be divided into brushless DC motors and brushed DC motors according to their structure and working principle.

Brushed DC motors can be divided into permanent magnet DC motors and electromagnetic DC motors.

Electromagnetic DC motors are divided into series excited DC motors, parallel excited DC motors, separately excited DC motors, and compound excited DC motors.

Permanent magnet DC motors are divided into rare earth permanent magnet DC motors, ferrite permanent magnet DC motors, and aluminum nickel cobalt permanent magnet DC motors.

2) AC motors can also be divided into single-phase motors and three-phase motors.

2. According to their structure and working principle, they can be divided into DC motors, asynchronous motors, and synchronous motors.

1) Synchronous motors can be divided into permanent magnet synchronous motors, reluctance synchronous motors, and hysteresis synchronous motors.

2) Asynchronous motors can be divided into induction motors and AC commutator motors.

Induction motors can be divided into three-phase asynchronous motors, single-phase asynchronous motors, and shielded pole asynchronous motors.

AC commutator motors can be divided into single-phase series excited motors, AC/DC dual-purpose motors, and repulsion motors.

3. According to the starting and operating modes, it can be divided into capacitor starting single-phase asynchronous motor, capacitor running single-phase asynchronous motor, capacitor starting single-phase asynchronous motor, and phase separated single-phase asynchronous motor.

4. Divided by purpose: drive motors and control motors.

1) Electric motors for driving can be divided into: electric motors for power tools (including drilling, polishing, grinding, slotting, cutting, expanding, etc.), electric motors for household appliances (including washing machines, electric fans, refrigerators, air conditioners, recorders, video recorders, DVD players, vacuum cleaners, cameras, hair dryers, electric shavers, etc.), and electric motors for other general small mechanical equipment (including various small machine tools, small machinery, medical equipment, electronic instruments, etc.).

2) Control motors are further divided into stepper motors and servo motors.

5. According to the structure of the rotor, it can be divided into cage type induction motors (formerly known as squirrel cage asynchronous motors) and wound rotor induction motors (formerly known as wound type asynchronous motors).

6. According to the operating speed, it can be divided into high-speed motors, low-speed motors, constant speed motors, and speed regulating motors. Low speed motors are divided into gear reduction motors, electromagnetic reduction motors, torque motors, and claw pole synchronous motors.

Adjustable speed motors can be divided into stepped constant speed motors, continuously variable speed motors, stepped variable speed motors, and continuously variable speed motors. They can also be divided into electromagnetic speed motors, DC speed motors, PWM frequency conversion speed motors, and switched reluctance speed motors.

The rotor speed of an asynchronous motor is always slightly lower than the synchronous speed of the rotating magnetic field.

The rotor speed of a synchronous motor remains synchronous regardless of the load size.

Folding DC motor

Working principle of DC generator

The working principle of a DC generator is to convert the alternating electromotive force induced in the armature coil,

The principle of using a commutator in conjunction with an electric brush to convert it into a direct current electromotive force when it is drawn out from the end of the electric brush.

The direction of induced electromotive force is determined according to the right-hand rule (the magnetic induction line points towards the palm of the hand, the thumb points towards the direction of the conductor's movement, and the other four fingers point towards the direction of induced electromotive force in the conductor).

Working principle of DC motor

The direction of force acting on a conductor is determined by the left-hand rule. This pair of electromagnetic forces forms a torque acting on the armature, which is called electromagnetic torque in a rotating motor. The direction of the torque is counterclockwise, attempting to make the armature rotate counterclockwise. If this electromagnetic torque can overcome the resistance torque on the armature (such as the resistance torque caused by friction and other load torques), the armature can rotate counterclockwise.

Principle and structure of DC motor

DC motor is an electric motor that operates on DC working voltage and is widely used in recorders, video recorders, DVD players, electric shavers, electronic watches, toys, etc.

1、 Electromagnetic DC motor

An electromagnetic DC motor consists of stator magnetic poles, rotor (armature), commutator (commonly known as commutator), brushes, casing, bearings, etc,

The stator magnetic pole (main magnetic pole) of an electromagnetic DC motor is composed of an iron core and an excitation winding. According to the different excitation methods (formerly known as excitation), it can be divided into series excited DC motors, parallel excited DC motors, separately excited DC motors, and compound excited DC motors. Due to different excitation methods, the law of stator magnetic flux (generated by the excitation coil of the stator magnetic pole after being energized) is also different.

The excitation winding and rotor winding of a series excited DC motor are connected in series through electric brushes and commutators. The excitation current is proportional to the armature current, and the magnetic flux of the stator increases with the increase of excitation current. The torque is approximately proportional to the square of the armature current, and the speed rapidly decreases with the increase of torque or current. Its starting torque can reach more than 5 times the rated torque, and the short-term overload torque can reach more than 4 times the rated torque. The speed change rate is large, and the no-load speed is very high (generally not allowed to operate under no-load). Speed regulation can be achieved by connecting external resistors in series (or parallel) with the series excitation winding, or by swapping the series excitation winding in parallel.

The excitation winding of a parallel excited DC motor is connected in parallel with the rotor winding, and its excitation current is relatively constant. The starting torque is proportional to the armature current, and the starting current is about 2.5 times the rated current. The speed slightly decreases with the increase of current and torque, and the short-term overload torque is 1.5 times the rated torque. The rate of change in rotational speed is relatively small, ranging from 5% to 15%. Speed can be adjusted by weakening the constant power of the magnetic field.

The excitation winding of the DC motor is connected to an independent excitation power supply, and its excitation current is also relatively constant. The starting torque is proportional to the armature current. The speed variation is also between 5% and 15%. The speed can be increased by weakening the magnetic field constant power or reduced by lowering the voltage of the rotor winding.

In addition to parallel excitation windings, the stator poles of a compound excited DC motor are also equipped with series excitation windings (with fewer turns) connected in series with the rotor winding. The direction of magnetic flux generated by the series winding is the same as that of the main winding. The starting torque is about 4 times the rated torque, and the short-term overload torque is about 3.5 times the rated torque. The speed change rate is 25%~30% (related to the series winding). The speed can be adjusted by weakening the magnetic field strength.

The commutator segments are made of alloy materials such as silver copper and cadmium copper, and are molded from high-strength plastic. The electric brush slides in contact with the commutator, providing armature current to the rotor winding. The brushes of electromagnetic DC motors generally use metal graphite brushes or electrochemical graphite brushes. The iron core of the rotor is made of stacked silicon steel sheets, usually 12 slots, embedded with 12 sets of armature windings, connected in series between each winding, and then connected to 12 commutator segments separately.

Excitation method of DC motor

The excitation method of a DC motor refers to the problem of how to supply power to the excitation winding, generate excitation magnetic flux potential, and establish the main magnetic field. According to different excitation methods, DC motors can be divided into the following types.