There are many forms of servo drive in the industry, and there are big differences in technical configuration. When we researched the market information, some users of injection molding machines reported that they felt that the power was not enough when using certain brands of servo injection molding machines. The model of the variable pump, by understanding the main reason is that the power configuration is not enough, on some aspects of this industry and the user's questions, let's talk about some characteristics and technical points of the servo drive:

1. What is "servo"?

"Servo" in English is "Servo", which is derived from the Greek meaning of "slave"; in modern industry, it is interpreted as a system that implements command requirements. In the application of injection molding machinery, the servo system receives the command signal of the computer, and realizes precise speed and pressure control by changing the speed and torque of the servo motor. During the execution process, the feedback is detected by the rotary transformer and the pressure sensor, and the servo system performs the servo system. Correction compensation, that is to say, the speed and pressure realize closed-loop control, so that the operation process of the injection molding machine is stable and the product qualification rate is high;

Second, why do some models on the market feel inadequate?

The current mainstream form of servo injection molding machine is to use servo motor to drive the oil pump to achieve the corresponding mechanical action. When the injection molding machine is “too small” in the matching of the main power units such as the drive, motor and oil pump, the pressure will not drop. The phenomenon, when the situation is serious, the motor rises sharply, the motor overload protection stops, which seriously affects the production plan. This is mainly due to mechanical design, product positioning, cost positioning and other reasons.

Third, how to use servo injection molding machine to play the advantages of energy saving, stability and reliability?

1. Firstly, the servo system with high power and torque should be selected, which will directly affect the overload capability during high pressure operation. The ultimate performance of the machine can be tested by physical test, for example: using the highest pressure for a long time load (recommended not less than 40) Seconds), the state of the machine is detected after a number of cycles;

At present, the magnetic steel of the servo motor has different grades of M, S, H and SH. SH is the highest level, and the magnetic flux is the largest (that is, the number of magnetic lines per unit area). The high torque output is more advantageous, and its overload capability is good; Avoid using a cheaper servo system. Because the servo system is overloaded for a long time, the servo motor will be prone to demagnetization, and the power of the machine will drop.

2, pay attention to the connection mode of the motor and the oil pump, whether to use a reliable coupling and bracket structure, because the servo motor will frequently accelerate, decelerate, brake, reverse, and all within a few tens of milliseconds. This will affect the axial concentricity and damping during the driving process, which will affect the service life of the motor bearings and oil pumps.

3. Pay attention to the data such as the displacement and speed of the oil pump that affect the efficiency of the machine. The larger the displacement of the pump at the same speed, the higher the operating efficiency of the machine. The highest flow output requirements and speed should be considered in the selection of the pump displacement. Relationship, under the premise of ensuring the highest flow output requirements, it is recommended that the speed design be within a reasonable safety range to ensure the reliability and service life of the servo drive system. The low speed design also brings faster response speed, but this will Increasing the cost of the machine involves the price positioning of the machine. Both the user and the machine manufacturer need to have a forward-looking perspective.