Demolding of ophthalmic lenses during the manufacture thereof
View Patent ↗Methods, devices, and systems for demolding lens mold assemblies are described in which the lens mold assemblies are positioned below a puncher header each with at least one punch pin. The puncher header is then moved against the lens mold assemblies so that the at least one punch pin of each puncher punches through a lens mold layer of a first mold part to then push against a second lens mold layer of a second mold part to separate the two parts in a demolding process.
1. A method of manufacturing a molded ophthalmic lens, comprising:
providing a molded ophthalmic lens in a lens mold assembly, the lens mold assembly comprising a first mold part and a second mold part coupled to the first mold part;
placing the lens mold assembly under a puncher; said puncher comprising at least one punch pin comprising a tip;
moving the puncher along an axis within a cylinder defined by the lens mold assembly;
puncturing through a surface layer of the first mold part; and
pushing against a surface layer of the second mold part to separate second mold part from the first mold part.
2. The method of claim 1 , wherein the first mold part is a female mold comprising a concave lens forming surface and a wall having a first axial end and a second axial end.
3. The method of claim 2 , further comprising supporting the second axial end by a loading palette during the puncturing step.
4. The method of claim 1 . wherein the first mold part has a wall defining a cylinder, and the method further comprises moving the at least one punch pin within the cylinder defined by the wall of the first mold part to puncture the surface layer.
5. The method of claim 1 , further comprising supporting an axial end of the first mold part with a support palette during the puncturing step.
6. The method of claim further comprising stripping the first mold part from the at least one punch pin following the puncturing step.
7. The method of claim 6 , wherein the step of stripping the first mold part comprises using a stripper plate located above the support palette.
8. The method of claim 6 , wherein the step of stripping the first mold part comprises using a stripper column located with the puncher,
9. The method of claim I, wherein the method further comprises the step of transferring least one of the first mold part or the second mold part for further processing.
10. The method of claim 1 , wherein the ophthalmic lens is a contact lens, and the method further comprises: providing a polymerizable contact lens formulation in the lens mold assembly; polymerizing the polymerizable contact lens formulation in the lens mold assembly to form a polymerized molded contact lens; separating the polymerized molded contact lens from one of the separated mold parts to produce a separated contact lens; contacting the separated contact lens with a liquid; placing the separated contact lens in contact lens package; sterilizing the contact lens in the contact lens package to produce a sterilized contact lens: or combinations thereof.