The working principle of a servo motor is to automatically control any change in the target. It mainly relies on pulses for positioning, which can achieve precise positioning. DC servo motors are divided into brushed and brushless motors. There are many types of servo motors in applications, such as speed mode and torque mode. Next, we will introduce them to you.
I. Working Principle of Servo Motor
1. A servo system is an automatic control system that enables the output controlled variables, such as the position, orientation, and state of an object, to follow any changes in the input target (or given value).
2. Servo motors mainly rely on pulses for positioning. Basically, it can be understood that when a servo motor receives one pulse, it will rotate by the angle corresponding to one pulse, thereby achieving displacement. Because the servo motor itself has the function of emitting pulses, it will emit a corresponding number of pulses for each rotation angle.
3. It forms a response, or closed loop, with the pulses received by the servo motor. In this way, the system knows how many pulses were sent to the servo motor and how many pulses were received back. This allows for very precise control of the motor's rotation, thereby achieving precise positioning down to 0.001mm.
4. DC servo motors are divided into brushed and brushless motors. Brushed motors are low in cost, simple in structure, have high starting torque, wide speed range, and are easy to control. However, they require maintenance, which is inconvenient (replacing carbon brushes), generates electromagnetic interference, and has environmental requirements. Therefore, they can be used in cost-sensitive general industrial and civilian applications.
II. Types of Servo Motor Applications
1. Speed mode, for example, when rapid acceleration and deceleration are required. The most typical example of this application is the light spheres suspended above the stage, which are used for rapid acceleration and deceleration.
2. Torque Mode (also known as torque mode): This mode provides a constant output force with unchanging torque. Examples include wire EDM machines and diamond cutting machines. The spindle and feed axes of these machine tools are typically servo motors, primarily for this function (along with two other functions).
3. Position Mode. This mode allows for precise position control, which essentially means controlling the rotation angle of the servo motor. The degree of rotation of a motor is counted by an encoder.
