Latest Injection Molding Machine Technologies

Injection molding machines divided into three categories based on technology used:

1. Hydraulic
2. Hybrid
3. All electric

Hydraulic Injection Molding Machines

Hydraulic machines are old fashioned machines consume more energy. In hydraulic injection molding machine hydraulic system is used to injection, mold open and close, and clamp pressure. In earlier versions of hydraulic systems contactors were used to on and off the motor. It means there were only two positions either motor is fully on or off. Motor runs at full speed even low pressure is required. When low pressure is required a pressure relief valve is installed to control the pressure. The largest hydraulic press is available in 7000 tons.

All Electric Injection molding machine

A new technology introduced in injection molding machines is All Electric injection molding machines. This technology is energy efficient and more presie and oil free. It is absolutly new technology used in injection molding machines. It usesis directly electric enegry to presses, open and close mold. This new technology is more efficient than hydraulic in which 20% to 30% energy is wastes in two converstions 1st electrical power to hydraulic and then 2nd from hydraulic power to mechanical power. Servo motor technology is more precise than inverter and AC motor both are used for same surpose to reduce or control the speed of motor. The largest all-electric press available in 3300 tons.

Difference	All-electric	Hydraulic
Precise	High	Less than All-electric
Repeatability	Good	Not as good as All-electric
Noise level	Very low 60 db	High
Price	High	Less than all electric
Hydraulic Oil	Oil free	Used
Motors used	Servo	Inverter/AC or DC
Maintenance	Less maintenance required	High maintenance due to hydraulic

In all-electric IMM all functions like clamp and injection are done by the servo motors.

Servo motors

Servo motors are generally an assembly of four things:

1. DC motor
2. gearing set
3. control circuit
4. Position-sensor (usually a potentiometer)

The position of servo motors can be controlled more precisely than those of   standard DC motors, and they usually have three wires (power, ground &).Servo motors are equipped with an encoder, feedback system. Didvided into two catagories.

1. AC servo motors
2. DC servo motors

Hybrid Injection Molding Machine

Complete hydraulic injection molding machine and all electric molding machine have their advantages and disadvantages. As all-electric breakdown maintenance is very costly. To overcome this a hybrid injection molding machine itroduced. Hybrid IM machines have the advantages of both all-electric and hydraulic machines. In hybrid except injection and clamping all other functions are performed with hydraulic. Hybrid IM machine is relatively cheaper than all-electric and expensive than hydraulic injection machine.