Patent ID: 6270333
Filing Date: 2001-08-07
Classification: B29C

Abstract:
A mold clamping apparatus for an injection molding machine, for closing and opening a mold including a stationary mold and a movable mold and for clamping the mold closed, said mold clamping apparatus comprising:a stationary platen fixedly holding the stationary mold;a movable platen fixedly holding the movable mold and disposed opposite to the stationary platen;tie bars for connecting the movable platen to the stationary platen in a manner that the movable platen moves toward and away from the stationary platen;movable platen driving means being electrically driven for moving the movable platen along the tie bars to close and open the mold;movable platen fixing means for fixing the movable platen directly to the tie bars at a set position immediately before a position where the movable mold is closed; andclamping force applying means for applying an intensified mold clamping force to the molds, said clamping force applying means including:a hydraulic cylinder actuator connected with each of at least some of the tie bars directly to apply the intensified mold clamping force to the movable platen when the movable platen is fixed to the tie bars by the movable platen fixing means;a pressure intensifier having therein an intensifier pressure chamber communicating with each hydraulic cylinder actuator;a pressure applying member fitted in the intensifier pressure chamber to apply pressure to hydraulic fluid in the intensifier pressure chamber; andpressure applying member driving means being electrically driven for axially shifting the pressure applying member.