초록

A method of maintaining contact between the injected molded resinous optical surface and the mold by rapid filling of the mold through a restricted orifice and by mechanically moving the mold against the resin as it cools and shrinks.

대표청구항 ▼

A method of molding optical lenses by the steps of heating and melting a resinous lens material, forcing with pressure the heated and melted resinous material into a runner tube and through a tapered restricted opening at the edge of the mold cavity, the velocity of the melted resinous material bein

A method of molding optical lenses by the steps of heating and melting a resinous lens material, forcing with pressure the heated and melted resinous material into a runner tube and through a tapered restricted opening at the edge of the mold cavity, the velocity of the melted resinous material being increased upon passing through the tapered restricted opening and the temperature of the melted resinous material is increased by internal frictional forces upon passing through the tapered restricted opening and the viscosity of the melted resinous material is lowered upon passing through the tapered restricted opening, filling the lens mold cavity with the heated low viscosity resinous material, by allowing the melted lens material to rapidly move from the tapered restricted opening across the lens mold cavity, the molten lens material entering at the restricted opening and moving across to the opposite edge of the lens cavity to a point 180°removed from the entry gate and filling the lens cavity from the center line toward the two sides located 90°removed from the filling opening and providing air vents having a opening width of from one to three thousandths of an inch at the sides 90°removed from the filling opening, allowing the pressure within the mold cavity to equal the pressure present in the runner tube, allowing the heated resinous material to cool until the resinous material present in said restricted opening is solidified and sealing the molten lens material within the mold cavity, providing one stationary and one moveable opposed curved optical mold surfaces within said mold cavity, applying external force to the moveable optical mold surface moving said optical mold surface against the heated and melted resinous material present within the mold cavity, maintaining the external applied force on the resinous material and allowing the resinous material to cool and become a solid, opening the mold and removing the resinous optical lens.