Apparatus for molding a product of synthetic resin

An apparatus for molding a product of synthetic resin, comprising:

• a mold assembly having a die plate, first and second mold dies which define a mold cavity therebetween, and said first mold die being mounted on said die plate, said first mold die comprising a fixed member fixed to said die plate, at least two movable members which are respectively displaceable in substantially perpendicular directions away from each other, each of said movable members being mounted on said die plate and further being displaceable away from said fixed member to open said first mold die, and a resilient member for substantially perpendicularly contacting said movable members and urging said movable members toward said fixed member to assemble said first mold die together wherein said fixed member of the first mold die has a product forming surface facing said mold cavity and composed of at least one of porous material and suction holes, said fixed member having a vacuum chamber defined therein, said movable member having a vacuum member defined therein and communicating with said vacuum chamber in said fixed chamber through a vent hole, further including a vacuum pump communicating with said vacuum chamber in said fixed member, whereby said vacuum pump and said vacuum chamber in said fixed and movable members jointly provide an evacuating circuit for evacuating said mold cavity.