Compression apparatus for molding, injection compression molding machine, and injection compression molding method using the compression device

An injection compression molding machine which includes a die comprising a movable mold and a stationary mold, and in which molten resin is charged into said die and said movable mold is advanced so as to apply compression force to the molten resin, to thereby mold the molten resin, said injection compression molding machine comprising:

• a compression apparatus for molding which includes first and second slant portions each of which has a slant face slanted with respect to an advancement direction of said movable mold and which are arranged along said advancement direction of said movable mold, said slant face of said first slant portion being in surface contact with said slant face of said second slant portion, and said first slant portion and said second slant portion being moved relative to each other in a direction perpendicular to said advancement direction of said movable mold, to thereby generate pushing force which pushes said movable mold toward said stationary mold, wherein
• a plurality of sets each including said first slant portion and said second slant portions which move relative to each other in a same direction are provided in a plane which extends perpendicular to said advancement direction of said movable mold, any one of said first slant portions and said second slant portions being engaged with a single interlock plate which is disposed to be movable in said moving direction of said first and second slant portions, wherein said single interlock plate is a plate-shaped rigid body which has an elongated hole extending along said moving direction of said first and second slanted portions;
• said compression apparatus for molding pushes said movable mold toward said stationary mold so as to compress the molten resin which has been charged into said die;
• a drive mechanism for driving said first and second slanted portions is disposed inside said elongated hole of said single interlock plate;
• and
• wherein said plurality of sets of said first and second slanted portions have said first slanted portions moving relative to said second slanted portions in a different direction than said moving direction and are provided in a plane which extends perpendicular to the advancement direction of the movable mold and any one of said first and second slanted portions are engaged with said single interlock plate disposed to be movable in a same direction as said moving direction of said first and second slanted portions, and said first and second slanted portions, having moving directions which differ from each other, are engaged with each other via a synchronization mechanism, wherein said synchronization mechanism comprises a link which is pivoted at a central portion thereof and is engaged with each of said first and second slanted portions at opposite end portions thereof.

An injection compression molding method comprising the method steps of:

• providing a compression apparatus for molding having first and second slant portions each of which has a slant face slanted with respect to an advancement direction of a movable mold which advances toward a stationary mold of a die into which molten melt is injected, said first and second slant portions being arranged along said advancement direction of said movable mold, said slant face of said first slant portion being in surface contact with said slant face of said second slant portion being moved relative to each other in a direction perpendicular to said advancement direction of said movable mold, to thereby generate pushing force which pushes said movable mold toward said stationary mold;
• providing a plurality of sets each including said first slant portion and said second slant portions, which move relative to each other in a same direction, in a plane which extends perpendicular to said advancement direction of said movable mold, any one of said first slant portions and said second slant portions being engaged with a single interlock plate which is disposed to be movable in said moving direction of said first and second slant portions, wherein said single interlock plate is a plate-shaped rigid body which has an elongated hole extending along said moving direction of said first and second slanted portions;
• after injection of the molten resin into said die, said compression apparatus for molding is operated to push said movable mold toward said stationary mold so as to compress the molten resin which has been charged into said die;
• using a drive mechanism to drive said first and second slanted portions, said drive mechanism being disposed inside of said elongated hole of said single interlock plate;
• and
• moving said first slanted portions of said plurality of sets of said first and second slanted portions relative to said second slanted portions in a different direction than said moving direction, providing said first slated portions in a plane which extends perpendicular to the advancement direction of the movable mold, and engaging any one of said first and second slanted portions with said single interlock plate disposed to be movable in a same direction as said moving direction of said first and second slanted portions, wherein said first and second slanted portions, having moving directions which differ from each other, are engaged with each other via a synchronization mechanism, wherein said synchronization mechanism comprises a link which is pivoted at a central portion thereof and is engaged with each of said first and second slanted portions at opposite end portions thereof.

The injection compression molding method according to 14, wherein a set of said first slant portion and said second slant portion is provided in a plane which extends perpendicular to said advancement direction of said movable mold, any one of said first slant portion and said second slant portion being engaged with an interlock plate which is disposed to be movable in said moving direction of said first and second slant portions;

• any one of first auxiliary slant portions corresponding to said first slant portions and second auxiliary slant portions corresponding to said second slant portions are fixed to said interlock plate at positions spaced away from said first and second slant portions along said moving direction of said slant portions;
• each of said first and second auxiliary slant portions has a slant face which is slanted with respect to said advancement direction of said movable mold, said first and second auxiliary slant portions are arranged along said advancement direction of said movable mold, and said slant faces of said first and second auxiliary slant portions are in surface contact with each other;
• and
• after injection of the molten resin into said die, said compression apparatus for molding is operated to push said movable mold toward said stationary mold so as to compress the molten resin which has been charged into said die.