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Nowadays, with the continuous development of technology, AC servo motor technology gradually replaced the DC motor as the leading executive motor with its excellent cost performance. The mature technology of AC servo system also makes the market develop rapidly and become one of the supporting technologies of industrial automation. So what are the main functions of servo system and how is it classified? Continue and you will learn about that.

Rewinding machine is widely in the re-winding operation and inspection operation of the material in plastics, printing, composite, coating, bag making, and coating film. With double servo automatic tension control, it can operate in the positive and reverse direction. At the same time, it has the fixed point memory stop function, which can quickly reverse to the defect position. The equipment is composed of the unreeling mechanism, take-up mechanism, deviation rectifying device, material delivery guide roller, photoelectric device, tension detection, synchronous strobeflash, length detection, operation interface, electrical control and other parts.

Motion controller usually adapts two types of command mode to control servo motor:
Digital pulse
This mode is similar to the control mode of stepper motor. The motion controller sends"pulse/direction" type pulse command signal to servo driver, when servo driver operates in position control mode, position closed loop is completed by servo driver. This mode of servo motor has the advantages that system debugging is simple and is difficult to cause interference, but has the disadvantage that the response of servo system is slightly slow.
Analog signal
In this mode, motion control system sends/-10V analog voltage command to servo driver and receives position feedback signals from position detection elements, such as motor encoder or linear grating, etc., when servo driver operates in speed control mode, position closed loop is completed by motion controller. Europe and America servo products mostly adapt such operation mode, which has the advantage that response of servo is rapid, but the disadvantage is that they are sensitive to site interference and debugging is complex.

There are some notes for the users when installing and using the servo motor. Take care of servo motor and it can work better and longer. The article briefly illustrates some precations for installation and usage of servo motor from serveral aspects: oil and mater resistant protection, tension reduction for servo motor cable, allowable shaft terminal load and so on.

1. Servo motor does not run when the pulse is output, how to solve the problem?

1. Monitor the current pulse output value of controller and check if pulse output indicator lamp flashes to confirm 
   that the controller has performed command pulse and has output pulse normally.
2. Check if the control cable, power cable, encoder cable between controller and driver are matched incorrectly damaged or contacted poorly.
3. Check if the brake of servo motor equipped with brake has been turned on.
4. Monitor the panel of servo driver to confirm if the pulse command has been input.
5. Run command is normal.
6. For control mode, always choose position control mode.
7. Check if the type of input pulse set by servo driver matches with that of command pulse.
8. Ensure that positive side drive prohibition, negative side drive prohibition signals and deviation counter reset 
   signal are not input and the servo motor runs normally if load is removed, then check the mechanical system.

As the executive element of mechanical equipment, servo motor is used widely in servo system. When using servo motor, there is a phonomena of overheating when working. As you are not familiar with the principle and structure of servo motor, how to judge whether the heating value is normal or not? And how to reduce the heating value of servo motor?

Users often feel confused about the three braking ways of servo motor: electromagnetic braking, regenerative braking, and dynamic braking. As a result, they selected the wrong accessories. The article will tell you the differences among them and give some tips about the accessories selection.

One of the most significant advantages of stepper motor is that it can be controlled accurately in open loop system because the rotor position can be determined only by tracking the input step pulse, but overheating problem occurs easily in stepper motor, so how to solve this problem if such condition occurs?

In the specific occasion, when the terminal load is stable, the action is simple and the motor basically runs at low speed, it is appropriate to choose the stepper motor with low cost and easily controlling. However, when terminal load fluctuation range is large, action is simple and the motor basically runs at low speed, if still choosing the stepper motor, a series of troubles are coming. In fact, in such situation, servo motor should be chosen, as the comprehensive cost will decline considering many factors.

Industrial sewing machine control system is a comprehensive and strong technology, which involves many aspects of knowledge, such as the principles of mechanical and electrical equipment, operation technology and so on. As the core running component in industrial sewing machine, the servo system plays a key function in running of this equipment.
This control system mainly includes special controller, AC servo system and stepper motor system, in which the controller mainly consists of main control board and two step drive boards. So it can directly sends pulse to control stepper motors in axis-X and axis-Y, while the needle is controlled by servo motor through needle bar directly connected with coupling.

For stepper motor specification, the operating temperature range for stepper motor should be 0～50℃ while humidity should be 20%～90%RH, and storage temperature should be -20～70℃ while humidity should be 15%～95%RH.

With global environmental crisis becoming intensified, energy saving and emission reduction has become one target of the automobile industry. Resistance welding and car body manufacturing is inseparable. Depending on its characteristics like wide speed regulation ratio, big rotational torque and high accuracy, resistance welding machines pressed by servo motor plays an important role in welding. It can improve control over welding force and realize accurate control over depth of fusion of welding force and welding points. In addition, servo motor itself has favorable dynamics and it can improve speed from zero to rated speed in several seconds. With its advantages, servo motor has a successful application in resistance welding machine.

Computerized embroidering machine can realize traditional manual embroidery with high speed and high efficiency, and meet the requirement of multi-level, multi-function, unity and perfection which is out of reach of manual embroidery. Servo motor via its advantages plays an important role in various embroidery machines, to make sure the high quality in products.

Marketing of stainless steel servo motors can help producers of the food industry improve design of hygiene machine. Stainless steel servo motor can reduce extra hardware and improve cleanliness, reliability and performance of machines at the same time. The motors adopt smooth and round design which is easy for cleaning, since meat and fluid will not easily gather in surface. The motor is made of grade-300 stainless steel and it will have special treatment after finishing components to remove impurities and further improve corrosive protection performance. In addition, cable outlets of motors are sealed when they leave factory, which can improve product reliability to the utmost extent.

At present, robot has a rapid development especially industrial robot. However, robot should be improved in response speed, accuracy and technological level. Then, what is the key point? The key lies on core part of robot – servo motor.

Water jet, also called high pressure water jet cutting technique, is a special cold cutting and can realize cutting processing of any curves. Now it is widely used in industries like aviation, automobile, stone material, glass, metal, concrete and so on. Servo system takes its own advantages to the application in water jet cutting, which brings a lot of benefits, like high efficiency, low consumption, high cutting precision and high rate of finished products.

It is well known that torque of stepper motor is big in slow speed but it will drop sharply after it reaches above 600RPM, making stepper motor cannot be applied on occasions with high speed motion. Moreover, since positioning defects of stepper motor when it stop working will cause location errors, it cannot meet requirements of modern inkjet printers on high speed and high efficiency any longer. However, servo motor has characteristics like rapid response, high speed and high positioning accuracy, thus modern inkjet printers generally select motors of this kind as cloth feeding motor and small panel control motor, thus forming the situation of the high and medium-end market which centers on alternating servo motor system.

CNC Bending Machine is a machine to process metal plates and it mainly uses hydraulic system to blend panels into different shapes. In view of defects of the hydraulic system of traditional bending machine and characteristics of forming techniques and processes of equipment, it adopts servo drive, servo motor, and gear pump to adjust control system of flow and pressure of hydraulic system, which can reduce system energy consumption and temperature-rising of hydraulic oil, and improve operational reliability of equipment at the same time.

Illustrate the transformation process by taking dedicated servo system of injection molding machine: First, it should replace general asynchronous machine and dosing oil pump of the former system with servo motor and internal gear pump, add pressure transmitter in output direct pipes of oil pump and get rid of proportional pressure valve of the former system and corresponding amplifier board. Pick up analog signals whose pressure and flow are given from computer control of injection molding machine, transform them into 0-10V DC analog pressure signals through comprehensive processing and directly add them in input terminals of system pressure given signals and system flow given signals of servo drives, and connect pressure sensors in exit of oil pump with pressure feedback signal terminal of servo. Servo system can have PI adjustment through connected pressure and flow signals and change output torque and speed of servo motor so as to change output flow Qt and pressure p of oil pump to meet oil pressure and flow required by injection molding machine in various processes.

Fully automatic terminal crimping machine is kind of electromechanical integration machinery which integrates the three major processing procedures of the end of wiring harness, namely, cutting off, flaying. It can process a harness in an average speed of less than 1s and its flaying precision can reach to as high as 0.01ms. To meet the requirement, executive motor plays an important role. Due to its advantages, like high stability, small vibration and high precision, AC servo motor has become a first choice of most fully automatic terminal crimping machine as system executive motors. The AC servo motors are well applied to the wire harness processing of fully automatic terminal crimping machine, which can improve processing efficiency and precision.