Injection molding machine is also known as injection molding machine or injection machine. It is the main molding equipment for making thermoplastic or thermosetting plastics into various shapes of plastic products using plastic molding molds. Divided into vertical, horizontal, all-electric. The injection molding machine can heat the plastic and apply high pressure to the molten plastic so that it can be injected and fill the mold cavity.

The process of the injection molding machine is generally divided into several stages such as mold clamping, injection, melt, pressure holding, cooling, mold opening, etc. Each stage requires different working pressure and flow rate. For the oil pump motor, the injection molding process is changing The load state, in the hydraulic system of the fixed pump, the constant speed of the oil pump motor provides a constant flow, and excess hydraulic oil returns through the overflow valve. This process is called high-pressure throttling. According to statistics, the energy loss caused by high-pressure throttling is as high as 36% to 68%, and the power consumption of the oil pump motor of the injection molding machine accounts for 50% to 65% of the power consumption of the entire equipment. Therefore, the energy-saving transformation of frequency conversion technology for the oil pump motor of the injection molding machine has great energy-saving potential.

A. The advantages of frequency conversion energy saving of injection molding machine are as follows:

① The system has no impact, mechanical wear is reduced, and the service life of machinery and molds is extended.

② Once the installation and commissioning of the power saver is completed, it will run automatically after the power is turned on. The operation mode of the injection molding machine is exactly the same as before the transformation, and the operator does not need to be retrained.

③ Save electric energy, reduce energy consumption and production costs, and the power saving rate is generally more than 20%~50%.

④ Slow start and smooth stop, eliminate the hydraulic shock phenomenon, reduce the heat generation of hydraulic oil by 15% to 20%, reduce the consumption of cooling water, and effectively slow down the aging problem of hydraulic components, extend the life of the oil circuit system and save the usual maintenance A lot of expenses.

⑤ Improve the power factor of the power grid, save on-site compensation devices, and reduce the working environment noise of the motor significantly.

⑥ The inverter has multiple protections for the motor, such as overvoltage, overcurrent, and lack, to ensure stable operation of the device without manual adjustment.

⑦ Smooth soft-start mode reduces the impact on the motor and the grid, and the motor current is limited to 150% of the rated current.

B. The frequency conversion transformation of the injection molding machine is as follows:

① Power consumption of circulating cooling pump.

② Electric power consumption of hydraulic system oil pump;

③The electric energy consumption of the heater;

The power consumption of the hydraulic oil pump is up to 65% of the power consumption of the entire injection molding machine. Reducing its energy consumption is the focus of energy-saving transformation of the injection molding machine. The traditional quantitative pump is transformed into a variable frequency variable pump. The return flow through the overflow valve is minimized, the output of the oil pump matches the pressure and flow required for the operation of the whole machine, and there is no high-pressure overflow energy loss. Obviously improve the phenomena of high energy consumption, high oil temperature, high noise, short service life of machinery and seals in injection molding machines.