Ordinary motors, stepping motors, deceleration motors and servo motors here refer to DC micro motors. Usually, most of us are exposed to DC.
Motor, commonly known as "motor", refers to an electromagnetic device that realizes the conversion or transmission of electric energy according to the law of electromagnetic induction. It is represented by the letter "m" in the circuit (D in the old standard). Its main function is to generate driving torque as the power source of electrical appliances or various machines. Ordinary DC motor
Ordinary motors are more common in our ordinary time, including electric toys, razors and so on. Generally, there are only two pins. When the positive and negative poles of the battery are connected to the two pins, it will rotate, and then the positive and negative poles of the battery are connected to the two pins opposite to each other, and the motor will reverse. This kind of motor has the characteristics of too fast speed and too small torque. It is generally not directly used in smart cars.
When the DC power supply supplies power to the armature winding through the brush, the conductor under pole n on the armature surface can flow through the current in the same direction. According to the left-hand rule, the conductor will be subjected to the torque in the counterclockwise direction. Some conductors under pole s on the armature surface also flow current in the same direction. Similarly, according to the left-hand rule, the conductor will also be subjected to counterclockwise torque. In this way, the whole armature winding, that is, the rotor will rotate counterclockwise, and the input DC energy will be converted into the mechanical energy output on the rotor shaft. It is composed of stator and rotor. Stator: base, main magnetic pole, commutation pole, brush device, etc; Rotor (armature): armature core, armature winding, commutator, rotating shaft and fan, etc.
DC motor is a motor that converts DC electric energy into mechanical energy. It is widely used in electric drive because of its good speed regulation performance. According to the excitation mode, DC motors are divided into permanent magnet, separate excitation and self excitation, of which self excitation is divided into parallel excitation, series excitation and compound excitation.
Gear motor
The reduction motor is an ordinary motor with a reduction gearbox, which reduces the speed and increases the torque, so that the ordinary motor has a wider use space.
This kind of integrated body can also be called gear motor or gear motor. It is usually integrated by professional reducer manufacturers and supplied in complete sets after assembly. Reduction motors are widely used in iron and steel industry, machinery industry and so on. The advantage of using reduction motor is to simplify the design and save space. After the Second World War, the rapid development of military electronic equipment promoted the development and production of micro reduction motors and DC reduction motors in the United States, the Soviet Union and other countries. With the continuous development of the reduction motor industry, more and more industries and enterprises have applied to the reduction motor, and a number of enterprises have entered the reduction motor industry.
At present, Germany, France, Britain, the United States, China, South Korea and other countries maintain a leading level in the world market of micro reduction motors and DC reduction motors. China's Micro reduction motor and DC reduction motor industry was founded in the 1950s. In order to meet the needs of supporting weapons and equipment, it has gone through the stages of imitation, self-design, research and development and large-scale manufacturing. It has formed complete supporting systems such as product development, large-scale production, key parts, key materials, special manufacturing equipment and testing instruments An industrial system with an increasing degree of internationalization.
The reduction motor is generally used on the smart car, and the H-bridge scheme is generally used for the control of the motor, which is the principle of L298 chip.
The speed regulation generally adopts PWM (pulse width modulation) mechanism. The single chip microcomputer uses the timer to control the PWM wave with variable duty cycle or directly outputs the waveform of different sizes to control the overall speed of the car.
Stepper motor
Stepper motor is an open-loop control element stepper motor that converts electric pulse signal into angular displacement or linear displacement. In the case of non overload, the speed and stop position of the motor only depend on the frequency and number of pulses of the pulse signal, and are not affected by the load change. When the stepping driver receives a pulse signal, it drives the stepping motor to rotate a fixed angle in the set direction, called "step angle", and its rotation runs step by step at a fixed angle. The angular displacement can be controlled by controlling the number of pulses, so as to achieve the purpose of accurate positioning; At the same time, the speed and acceleration of motor rotation can be controlled by controlling the pulse frequency, so as to achieve the purpose of speed regulation.
servo motor
Servo motor, also known as executive motor, is used as an executive element in the automatic control system to convert the received electrical signal into angular displacement or angular speed output on the motor shaft. It is divided into DC and AC servo motors. Its main feature is that when the signal voltage is zero, there is no rotation, and the speed decreases at a uniform speed with the increase of torque.
The servo motor is mainly positioned by pulses. Basically, it can be understood that when the servo motor receives a pulse, it will rotate the angle corresponding to one pulse to realize displacement. Because the servo motor itself has the function of sending pulses, the servo motor will send a corresponding number of pulses every angle of rotation. In this way, It echoes with the pulse received by the servo motor, or closed loop. In this way, the system will know how many pulses are sent to the servo motor and how many pulses are received back. In this way, the rotation of the motor can be controlled accurately, so as to achieve accurate positioning, which can reach 0.001mm.
DC servo motor is divided into brushless motor and brushless motor. The brush motor has the advantages of low cost, simple structure, large starting torque, wide speed regulation range, easy control, needs maintenance, but it is inconvenient to maintain (replace carbon brush), and will produce electromagnetic interference, which has requirements for the environment. Therefore, it can be used in common industrial and civil occasions sensitive to cost.