Ejector apparatus

Abstract

An ejector apparatus includes a movable platen disposed facing a stationary platen and adapted for advancing and retracting movement along tie bars, a toggle mechanism disposed between the movable platen and a toggle support so as to advance and retract the movable platen, a servomotor fixed to the movable platen and including a stator and a rotor, a hollow shaft fixed to the rotor, a ball nut fixed to the hollow shaft, a ball screw shaft which is screw-engaged with the ball nut and is advanced and retracted by rotation of the ball nut, a cross head connected to the ball screw shaft so as to be advanced and retracted together with the ball screw shaft, and an ejector pin connected to the cross head. The hollow shaft is rotated by driving the servomotor, thereby advancing the cross head. With this operation, the ejector pin is advanced to push out a molded product. Since no timing belt is needed, the durability of the ejector apparatus can be improved, and the peripheral area of an injection molding machine can be prevented from being dirtied.

Dependencies are inferred from the claim text.