Patent ID: 7214048

Claim:
A valve gate assembly for an injection molding machine comprising: a valve body disposed on a lower surface of a manifold for controlling a flow of resin to a mold cavity, said valve body having a valve pin for opening/closing a gate by means of a raising/lowering operation said valve pin being provided with a thread on an outer circumferential surface of an upper end of the valve pin; a linear motor disposed upside the manifold, having a tubular rotor for providing raising/lowering force to the valve pin of the valve body and for generating rotation by means of supplied power, and controlled by a pulse signal for linear movement up and down in cooperation with the valve pin when the rotor performs forward/reverse rotation, wherein an inner circumferential surface of the rotor is screwed with the upper end of the valve pin; and a cooling block provided between the manifold and the linear motor, having cooling water channel circulating cooling water inside, and formed as a plate shaped member for blocking heat transmission.