Injection-molding machine for plastic with rotary and linear drive

摘要

An injection-molding machine for plastic, including an injection cylinder, a screw arranged in the injection cylinder and having a drive shaft, an electric motor, a mechanical rotary drive for connecting the electric motor to the drive shaft so that rotary motion is imparted to the drive shaft, and a linear drive for connecting the electric motor to the drive shaft so that linear motion is imparted to the drive shaft. The linear drive includes a pressure medium pump connected to the electric motor, and at least one synchronous piston-cylinder unit connected to the drive shaft and in fluid communication with the pump. A control unit is connected to the pump for controlling one of pump and motor absorption level. Hydraulic lines are configured and arranged to directly connect an input of the synchronous cylinder with an output of the pump and an output of the synchronous cylinder with an input of the pump in a closed hydraulic circuit.