초록 ▼

This invention provides a method and a mold for improving the release of a molded ophthalmic device from a mold. The method comprises the steps of: providing a first mold half and second mold half each having opposing top surfaces at least one of which has been hollowed out to define a cavity for fo

This invention provides a method and a mold for improving the release of a molded ophthalmic device from a mold. The method comprises the steps of: providing a first mold half and second mold half each having opposing top surfaces at least one of which has been hollowed out to define a cavity for forming said ophthalmic device and at least said first mold half further defining a boundary for a release element, said boundary is part of said cavity, said release element comprising a ramped surface, said cavity having a corresponding ramped surface, and said release element having its widest part near the top surface of said at least said first mold half that defines said release element therein. The mold of this invention has a hollowed-out portion as part of the cavity to provide a release element to the molded ophthalmic device.

대표청구항 ▼

1. A method of improving the release of a molded ophthalmic device from a mold comprising the steps of: providing a first mold half and second mold half each having opposing top surfaces at least one of which has been hollowed out to define a cavity for forming said ophthalmic device and at least sa

1. A method of improving the release of a molded ophthalmic device from a mold comprising the steps of: providing a first mold half and second mold half each having opposing top surfaces at least one of which has been hollowed out to define a cavity for forming said ophthalmic device and at least said first mold half further defining a boundary for a release element, said boundary is part of said cavity, said release element comprising a ramped surface, said cavity having a corresponding ramped surface, said release element having its widest part near the top surface of said at least said first mold half that defines said release element therein and locating said ramped surface of said release element therein and when said device in said mold shrinks, said ramped surface uses the shrinking forces of said device to direct said device out of said first mold half.2. The method of claim 1 further comprising the step of equipping said first mold half with air ejection, and locating said air ejection, whereby when air is ejected from said air ejection, said air will impinge upon said release element.3. The method of claim 1 further comprising the steps of placing a thermoplastic in said cavity, cooling said thermoplastic, and directing said ophthalmic device out of said first mold half using said ramped surface of said release element.4. The method of claim 3 further comprising the step of ejecting air out of said second mold half.5. The method of claim 4, further comprising the additional step of ejecting air out of the first mold half.6. The method of claim 1, additionally comprising the steps of placing a thermoplastic in said cavity, cooling said thermoplastic, and directing said thermoplastic out of said first mold half using said ramped surface of said release element, wherein said directing step is accomplished by the shrinkage of said ophthalmic device.7. A method of improving the release of a molded ophthalmic device from a mold comprising the steps of: providing a first mold half and second mold half each having opposing top surfaces at least one of which has been hollowed out to define a cavity for forming said ophthalmic device and at least said first mold half further defining a boundary for a release element said boundary is part of said cavity, said release element comprising a ramped surface, said cavity having a corresponding ramped surface, said release element having its widest part near the top surface of said at least said first mold half that defines said release element therein and wherein said release element has an annular shape and a triangular cross-section.8. The method of claim 7, wherein said ophthalmic device is a lens curve.9. The method of claim 7, wherein said ophthalmic device is a lens curve comprising a flange and said release element is located on said flange.10. The method of claim 7, wherein said first mold half comprises an insert, and said step of providing is accomplished by hollowing-out a portion of said insert to provide said boundary for said release element.11. A mold for forming an ophthalmic device, said mold comprising a first mold half and second mold half each having opposing top surfaces at least one of said top surfaces being hollowed out to define a cavity for forming said ophthalmic device, and at least said first mold half having a hollowed-out portion defining a release element, said hollowed-out portion being part of said cavity, said hollowed-out portion comprising a ramped surface, and being widest near the top surface of said at least said first mold half, wherein said ramped surface of said hollowed-out portion being located within the cavity to take advantage of a shrinking force of said ophthalmic device within said mold to move said molded device along said ramped surface of said cavity.12. The mold of claim 11, wherein said ophthalmic device is a lens curve.13. The mold of claim 11, wherein said release element has an annular shape.14. A mold for forming an ophthalmic device, said mold comprising a first mold half and second mold half each having opposing top surfaces at least one of said ton surfaces being hollowed out no define a cavity for forming said ophthalmic device, and at least said first mold half having a hollowed-out portion defining a release element, said hollowed-out portion being part of said cavity, said hollowed-out portion comprising a ramped surface, and being widest near the top surface of said at least said first mold half, wherein said release element is a lens curve and has a triangular cross-section.15. The mold of claim 11, further comprising air ejecting means.16. The mold of claim 15, whereby said ejecting means are located to direct air at said release element of said molded device.