light industry

For half a century, plastic has become one of the main materials for industrial and agricultural and civil engineering. Injection molding machine is a kind of special plastic molding machine. It makes use of the thermoplastic of plastics, and after proper heating and melting, the high pressure flows into the mold cavity to keep pressure and cool at a certain time. Become a variety of profiles and plastic products. In the injection molding machine to promote the application of frequency converter can achieve energy saving, improve productivity and product quality, reduce oil pollution and noise pollution, extend the life of the machine and other advantages, it will gradually promote the use of.
The process steps of the injection molding machine are as follows:
1, the lock mode: template fast, close to the fixed template, and confirmed that no foreign matter exists, the system turns to high pressure, the template lock.
2, injection nozzle and mold to Taiwan forward.
3, injection: the injection screw with a certain pressure and speed of the material tube front end of the melt injection mold cavity.
4, holding pressure, cooling: through this action, the mold cavity of the plastic products cooling.
5, the pre plastic: the traditional application of hydraulic motor driven screw and back, the hopper to join the plastic particles were pre pushed for pre plastic. Screw back to a predetermined position, stop turning, prepare the next injection.
6, injection mold Taiwan back.
7, top out products.
These movements in the traditional injection molding machine is to complete the hydraulic system. The pressure and flow rate of the oil pump and the different valve to provide the driving force and the movement speed of the hydraulic cylinder and the hydraulic motor.
As is known to all, the output power of the oil pump

Pt=p*qt=p*V*n (1)
And the theoretical torque of the oil pump:
Tt=1/2pi*p*V (2)
Type of P for the pressure, QT for the flow, V for the pump displacement, n for the pump speed, pi=3.14
The type of substitution (2) (1) type:
Tt *n Pt=2pi* (3)
If the energy loss in the hydraulic energy conversion process is neglected, the output power of the pump and the output torque of the motor can be approximately proportional to the speed of the motor. So it can be seen that when the system requires low flow rate, the power of the system is very low. But the actual situation is, because the motor is always running in the power frequency 50Hz state, and can not be based on actual demand to reduce its speed, thereby reducing the flow rate. So the excess hydraulic fluid through the overflow valve to tank, resulting in energy waste.
Yi Chuang Fei ECF330S series injection molding machine servo controller, the system pressure, flow and single loop and double closed loop, the hydraulic system according to the actual needs of the flow and pressure oil, to overcome the common quantitative pump system pressure relief produced by high energy consumption, high at the pre plastic, mold, plastic injection, such as flow phase motor according to the set speed, low flow during the packing and cooling stage reduces the rotation speed of the motor or the motor does not turn, the actual pump motor energy consumption greatly reduced.
And ECF330S series injection molding machine servo controller has a faster responding speed, pressure rise time and flow rate rise quickly to 50ms, improves the response speed of the hydraulic system, reducing action switching time, accelerate the whole operational tempo; automatic operation of injection molding machine hydraulic system, when the valve is opened, pressure system will be decreased instantaneously, the servo system can be within 50ms quickly add oil, recovery pressure to the set value. The pressure of high precision, high repeat accuracy, material temperature, low temperature, simple and convenient installation and debugging.
Ordinary VVVF speed control mode, that is, when the frequency of the frequency and voltage ratio to maintain a constant, then the flux of the motor constant. Because this way has not the speed feedback device that is not accurately reflecting the motor speed, and motor is also used is the three-phase asynchronous motor, the actual rotational speed of the rotor and the stator rotating magnetic field exists slip. When the external load changes, slip a change, but inverter and not this compensation, resulting in pump speed changes, causing the error in flow, directly led to the decline in the quality of the products.
Moreover, another drawback of VVVF is when the output frequency Hz, theoretical output voltage is 0V, stator flux Phi m is approximately 0, thus affecting the starting characteristic of motor, acceleration response is relatively slow. And for the injection molding machine, often in some such as injection action is completed, instantaneous high pressure, large flow, if the ring opening of general inverter. The pressure response is difficult to meet the requirements, the impact of injection pressure.

      Yi Chuang Fei ECF330S series servo controller uses the rotor field oriented control theory, namely of asynchronous motor current coordinate transformation, equivalent to a DC motor control method. In three-phase coordinate system under AC stator current IA, IB, IC through the three-phase / two phase transformation, equivalent into two-phase stationary coordinate system of alternating current I alpha and beta I and in the according to the rotor magnetic field directional rotation transformation can be equivalent to a synchronous rotating coordinate system of DC current, im. IM is equivalent to the DC motor excitation current, it equivalent to DC motor with torque proportional to the armature current. Because regardless of the motor in what state, running or static, the excitation current im always exist, and the size of the torque as long as the independent regulation of armature current it. So it can be make the asynchronous motor is always in a state of high dynamic, the RPM from the acceleration time of 1000 rpm to only 50ms, change the variable voltage variable frequency speed regulation system dynamic problems for the injection molding machine operation cycle follow very high.
Through the system of motor learning, accurate measurement of the resistance and inductance of stator, so that constant excitation current IM, and constant flux Phi m. And then because of the motor slip frequency
Omega s=K*it/ with m (4)
That is when the flux of m diameter is constant, the vector control system of slip frequency is proportional to the torque in the stator magnetic field frequency
1= + - + - S (5)
(the frequency of the rotor) can be controlled. This means that when the load fluctuates, inverter control part can rapidly calculate the actual slip frequency omega s, which gives the accurate stator rotating frequency, motor rotational speed remains unchanged, improves the motor with load changes in the operating stability.
In summary, Wilson hit a fly ECF330S series servo controller for the high dynamic, good stability, installation and debugging simple etc., which is suitable for the application of energy saving in injection molding machine