Characteristics of servo motor and Application of servo motor

There are many uses of servo motors, and we want to figure out where servo motors will be used. Then the principle of the motor to say a little about the function of the motor.

For those who are new to industrial automation, or those who are new to machinery, what exactly does a servo motor mean?

In fact, a very simple understanding is that the motor can be precisely calculated how much angle rotation, and can do real-time position feedback. Does it feel like the motor is being monitored by something in real time? It is the encoder that monitors the motor.

So the characteristics of the servo motor is very distinctive, servo characteristics determine the servo motor will be used in which equipment above.

1, high precision. High precision can control the position.

2, closed-loop control response is fast. Fast response can control the change of frequency and strength.

3, the entire motor movement is controlled, then the entire motor can be programmed through the digital signal, or pulse signal, to achieve the control. That is, complex motion.

Is not see this feeling or can not understand? The following talk you will understand. We will give the above three major features to translate into various movements in the industrial field.

1, Feature one: position control.

Since it can do a very accurate alignment work, it is not possible to do: labeling, do two product alignment lamination, do promotional table. Is it possible to control multiple products at the same time to form a regular movement: for example, the light ball above the stage. Is it possible to be very accurate in the printing machine, horizontal and vertical sewing, is it possible to do sawing.

So when we encounter any equipment that needs to be very accurate, we should first think of using servo. As for the final product design, is the use of servo motors, or stepper motors, depending on the cost and accuracy requirements of the degree.

The accuracy of servo motor is very much higher than that of stepper motor, 17-bit encoder servo motor, can reach 600 times the accuracy of ordinary stepper motor.

Among the devices that mainly reflect the servo position mode are:

Quilting and quilting machines, printing machines, dispensing machines, laminating machines, labeling machines, laminating machines, inspection and conveying tables in the field of electronic manufacturing, various types of transmission line bodies, shift machines, and various types of applications of flying shear chasing shear.

The hottest servo motor used on the top of the mask machine in 2020 is a 750W servo, controlled by PLC or motion controller, the main thing is the tension control (you can simply understand it as an advanced version of the position control mode) achieved by dragging the motion of the raw material strip of the mask.

For many friends just engaged in this line, if you look at a device to use servo, you ask each other the processing accuracy of this thing, whether it needs to be very high. If it does not need to be very high, then basically stepper motors may be fine.

2, Feature two: closed-loop control-related applications.

In fact, closed-loop control response fast this feature, we can first think of a variety of valves, switch applications is not it?

Then congratulations, you did answer the right.

Take our hottest ventilator now, the ventilator in the air and oxygen mixing time, is the use of servo valves.

In the corresponding fast, we first found the application area is: a variety of machine tools, you just see in the frequent change of speed, or frequent change of position of the machine tool basically use servo motors to provide power.

For example: all the axes of the 5-axis machine tools are servo-driven, which are mainly to provide position control. The second largest application market is the industrial robot market. An industrial robot uses six servo motors, whose precision control and high responsiveness to servo motors are very high.

In the rapid corresponding application of equipment such as: turning, milling, grinding CNC-type machine tools, servo turret punch, bending machines, laser cutting machines, etc.. There are all kinds of industrial robots, collaborative robots, AGV carts are using servo motors.

3, The characteristics of three: the precise control of continuous motion.

This feature is mainly a sublimated version of the first two features. For example: servo press, a 2000-ton servo press, you can do 20000N-m pressure above, he can control in real time, which is servo can control.

Another example: wire cutting equipment, this type of equipment is extremely common in the stone, polysilicon and other markets. This is a typical representative of the continuous reciprocating motion in the ability to achieve precise control.

If you must explain the application of servo motor scenario in general: control output force (professional name called torque) can be large or small, while the force can be done to change very uniform rise and decrease. That is to say, not only the final result can be controlled, but also to control the process of no point.

The following is the selection of servo motors:

There are many people will be in, servo motor can be used in which areas, when the servo mentioned constant speed, constant power.

In fact, the constant speed and power of the servo is the parameter that will be considered only at the time of selection.

To say something more pleasing, if you intend to design a device, you already have parameters about the production frequency of the device, and other electrical equipment. Then you don't know about servo motors, just go directly to a manufacturer of servo motors. Directly let people give you the selection of adapters. This will not want you to put in the effort to calculate.

If you do want to calculate yourself, how to select the servo motor, then you need to know basically how much torque is needed.

In general, the equipment in the design process, is a general understanding of how much torque needs, after all, you want to process the body equipment, how much force is needed, in fact, based on experience can be projected out. (You can not calculate, that is, you are a blank sheet of paper, slowly learn).

Actually should be considered torque (torque), motor power and torque calculation formula.

That is, T = 9550P / n

where:

P a power, kW; n a rated speed of the motor, r / min; T a torque, Nm.

The output torque of the servo motor must be greater than the torque required by the working machinery, and a safety factor is generally required.

Mechanical power formula: P = T * N / 97500

P: power unit W; T: torque, unit g/cm; N: speed, unit r/min.

How is the servo selection in reality?

In practice, you consult the manufacturer of the servo provided according to the parameters of the equipment. The sales engineer of the manufacturer, will see which motor is more suitable according to the speed and torque. Then get the field test, test according to the actual use of the parameters, and see if this servo motor used in this appropriate. For example, if the inertia is too large for this place, then it should be replaced by a servo with a small inertia. For example, the use of this place, the need for a holding brake, with oil seals, etc. are seen in the field use assessment. Servo selection is basically not a step in place.