Vertical injection molding machine

摘要

The vertical injection molding machine is provided with an electric servomotor which moves an injection drive unit up and down accompanying the rotation of a driven pulley via a ball screw mechanism, a timing belt by which the drive force of the electric servomotor is transmitted, and a driven pulley on which the timing belt is rotated, wherein an arc groove is formed on the driven pulley, and an election pin is provided which is inserted to the arc groove of the driven pulley when the timing belt is disconnected. When the election pin is inserted to the arc groove, the tip of the election pin applies pressure on an inclined portion by means of elastic force of a spring, slowing the rotational speed of the driven pulley and stopping the injection drive unit by an inner wall surface of the slowed driven pulley colliding with the ejection pin.

主权项

1. A vertical injection molding machine having a mold clamping unit that opens and closes a mold in a vertical direction, and an injection unit for injecting molten resin to a cavity of the mold when in a closed position; the machine comprising:
an injection drive unit formed to the injection unit; an electric servomotor as a drive source of the injection drive unit; a drive transmission belt to which a drive force of the electric servomotor is transmitted; a driven pulley on which the drive transmission belt is rotated; and a drive transmission unit for moving the injection drive unit having an injection screw up and down in the vertical direction along with the rotation of the driven pulley;wherein
the driven pulley has an arc groove formed along a circumferential direction thereof; a pin is provided to be inserted to the arc groove of the driven pulley when the drive transmission belt is disconnected or the electric servomotor is stopped; the arc groove has an inclined portion on a bottom surface formed in the circumferential direction of the driven pulley and having a groove depth becoming shallower along a direction opposite to a direction of rotation of the driven pulley; the pin is projected via an elastic member by an elastic force of the elastic member; and when the pin is projected and inserted in the arc groove, a tip portion of the pin applies pressure on the inclined portion by the elastic force of the elastic member to decelerate the rotational speed of the driven pulley, and by having an inner wall surface of the arc groove on the decelerated driven pulley collide against the pin, the movement of the injection drive unit up and down in the vertical direction along with the rotation of the driven pulley via the drive transmission unit is stopped.