The English term for linear motor is linear servomotor . In fact, the motors we commonly see today are rotary motors. This article will discuss the history of motor development, exploring its various functions, applications, and advantages.
1. The principle of a linear motor:
Within the industry, linear motors are also called "direct drive," so if you see "direct drive," it describes both linear motors and direct-drive (DD) motors. Remember, in the industry, "direct drive" includes DD motors.
The principle of a linear motor is not complicated. You can think of it as cutting a rotating induction motor along the radius and flattening it out; that is a linear motor.
If we compare it to a rotating motor, in a linear motor, what is equivalent to the stator of a rotating motor is called the primary; what is equivalent to the rotor of a rotating motor is called the secondary. When alternating current is applied to the primary, the secondary moves linearly along the primary under the action of electromagnetic force.
From the perspective of electromagnetic induction: the two types of linear motors in the figure above are (a) flat linear motors and ( b ) double flat linear motors.
Let's illustrate the change in electromagnetic force using the case in ( b ). The primary coil is located on both the top and bottom sides, with the permanent magnet providing a complete electromagnetic circuit. The wire in the secondary coil is just able to cut the electromagnetic induction lines, generating an Ampere force. According to the left-hand rule, we can see that the secondary coil will move to the left or right.
2. Types of linear motors:
1. Flat motor
2. DD motor (direct drive motor)
This type of direct-drive DD motor can provide greater torque.
3. Voice coil motor
In principle, voice coil motors are the same as linear motors; they can be simply understood as linear motors with fewer coil turns.
4. Major players in linear motors
Currently, there are not many major players in the linear motor market in China; they are mainly concentrated in South China.
In the domestic direct-drive servo field, Hikvision is the best in terms of drive technology, while Yacobes has the largest market share in the linear motor market. Currently, the main players in the direct-drive market are companies that have been using their equipment for a long time, such as Han's Laser.
5. Main application scenarios of linear motors
Its main applications include: laser equipment, non-standard 3C equipment such as testing and bonding, and the medical field where high cleanliness requirements are required.
6. Linear Motor Market Size
According to research by authoritative industry institutions, the overall market size for direct drive systems is approximately 2 billion yuan. It is still in its initial stage.
