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US3881683A Expired / Lapsed US ⏱️ 0.0 years remaining

Gasket for lens mold

Assignee: American Optical Corp
•
Filing: 1973-11-29
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Granted: 1975-05-06
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Expires: 1993-11-29
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Abstract

Abstract An annular gasket for molds used in the casting of minus power lenses. The gasket is provided with an internal flange having its opposite sides arranged as annular seats of appreciably different widths for receiving and supporting a pair of meniscus mold halves in a predetermined spaced coaxially aligned relationship. One mold half is used to form the concave ocular surface of a minus power lens to be cast and the seat supporting said one mold half is of greatest width for purposes of significantly reducing the diameter of the ocular surface and edge thickness of the cast lens.

Inventors

  • 👤 Donald B Whitney

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 02:04
CPC Classifications
B; B29; B29D; B29D11/00; B29D11/00009; B29D11/0048; B29D11/00528; B29C; B29C33/00; B29C33/0038; B29D11/00413; B29L; B29L2031/00; B29L2031/76; B29L2031/7602; Y; Y10; Y10S; Y10S425/00; Y10S425/044; Y10S425/808

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 216 words
In a lens casting mold including a pair of mold halves, one of said pair having a convex surface for molding concave ocular surfaces of lenses and the other of said pair having a concave surface for molding convex object side surfaces of the lenses and a resilient annular gasket for supporting said convex and concave surfaces of said mold halves in a predetermined spaced coaxially aligned relationship, the improvement comprising: said gasket having an inwardly directed flange providing a seat for one of said mold halves at each of its opposite sides and said flange having an inclined inner rectilinear casting face of a concavely obtusely angled configuration along its extension from one of said seats to the other of said seats, said inclined casting face providing said one of said seats with an appreciably greater width than the other, said one seat of greater width being concavely shaped for receiving said convex molding surface of said one mold half and minimizing the area of contact between said convex molding surface and the ocular surfaces of lenses cast thereby and said other seat of lesser width being convexly shaped for receiving said concave molding surface of said other mold half and maximizing the diametral size of the convex object side surfaces of lenses cast thereby.
Claim 2
Dependent Claim 216 words
In a lens casting mold including a pair of mold halves, one of said pair having a convex surface for molding concave ocular surfaces of lenses and the other of said pair having a concave surface for molding convex object side surfaces of the lenses and a resilient annular gasket for supporting said convex and concave surfaces of said mold halves in a predetermined spaced coaxially aligned relationship, the improvement comprising: said gasket having an inwardly directed flange providing a seat for one of said mold halves at each of its opposite sides and said flange having an inclined inner rectilinear casting face of a concavely obtusely angled configuration along its extension from one of said seats to the other of said seats, said inclined casting face providing said one of said seats with an appreciably greater width than the other, said one seat of greater width being concavely shaped for receiving said convex molding surface of said one mold half and minimizing the area of contact between said convex molding surface and the ocular surfaces of lenses cast thereby and said other seat of lesser width being convexly shaped for receiving said concave molding surface of said other mold half and maximizing the diametral size of the convex object side surfaces of lenses cast thereby.
Claim 3
Dependent Claim 30 words
The improvement according to claim 1 wherein said inner casting face of said flange is of a concavely right angular configuration along the direction of its extension between said seats.
Claim 4
Dependent Claim 201 words
A gasket for supporting mold halves of a lens casting mold wherein a first mold half has a convex surface for molding the concave ocular surfaces of lenses to be cast a second mold half has a concave surface for molding the convex object side surfaces of the lenses, the gasket comprising: an annular main body having an inwardly directed flange providing a seat for one of said mold halves at each of its opposite sides and said flange having an inclined rectilinear inner casting face of a concavely obtusely angled configuration along the direction of its extension from one of said seats to the other of said seats, said inclined casting face providing said one of said seats with an appreciably greater width than the other, said one seat of greater width being concavely shaped for receiving said convex molding surface of said first mold half and minimizing the area of contact between said convex molding surface and ocular surface of lenses cast thereby and said other seat of lesser width being convexly shaped for receiving said concave molding surface of said second mold half and maximizing the diametral size of the convex object side surfaces of lenses cast thereby.
Claim 5
Dependent Claim 201 words
A gasket for supporting mold halves of a lens casting mold wherein a first mold half has a convex surface for molding the concave ocular surfaces of lenses to be cast a second mold half has a concave surface for molding the convex object side surfaces of the lenses, the gasket comprising: an annular main body having an inwardly directed flange providing a seat for one of said mold halves at each of its opposite sides and said flange having an inclined rectilinear inner casting face of a concavely obtusely angled configuration along the direction of its extension from one of said seats to the other of said seats, said inclined casting face providing said one of said seats with an appreciably greater width than the other, said one seat of greater width being concavely shaped for receiving said convex molding surface of said first mold half and minimizing the area of contact between said convex molding surface and ocular surface of lenses cast thereby and said other seat of lesser width being convexly shaped for receiving said concave molding surface of said second mold half and maximizing the diametral size of the convex object side surfaces of lenses cast thereby.
Claim 6
Dependent Claim 23 words
A gasket according to claim 3 wherein said casting face of said flange is concavely right angular along its extension between said seats.

References Cited (Backward Citations)

US3331102A Cited
US3806079A Cited
US3761208A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-05-05 1978-11-04 1979-05-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-05-05 1982-11-04 1983-05-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-05-05 1986-11-04 1987-05-06 $7700.00 Window Closed / Lapsed

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