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US5316700A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for removing excess lens forming material

Assignee: WJ ACQUISITION CORP
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Filing: 1992-11-02
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Granted: 1994-05-31
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Expires: 2012-11-02
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Abstract

Abstract Process and apparatus for molding the front and rear surfaces of a contact lens in one step is disclosed. Two mold halves matable to form a contact-lens-shaped cavity and a cavity for excess lens forming material surrounding the cavity are provided. The improvement comprises providing the cavity for excess lens forming material with at least two openings and producing differential gas pressure across the openings to remove excess lens forming material.

Inventors

  • 👤 Paul J. Soye
  • 👤 Samuel Loshaek

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 09:47
CPC Classifications
B; B29; B29C; B29C33/00; B29C33/10; B29C33/0055; B29C43/00; B29C43/32; B29C43/36; B29C43/38; B29D; B29D11/00; B29D11/00009; B29D11/00038; B29D11/00057; B29L; B29L2011/00; B29L2011/0016; Y; Y10; Y10S; Y10S425/00; Y10S425/808; Y10S425/812

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 175 words
In a process for molding both sides of a contact lens comprising the steps of: a. providing a first mold half having a convex lens molding surface; b. providing a second mold half having a concave lens molding surface, said mold halves being matable to form a contact-lens-shaped cavity and an annular cavity surrounding the contact-lens-shaped cavity, the annular cavity having at least two openings in fluid communication with the environment outside the mated mold halves; c. depositing lens forming material on the concave lens forming surface in excess of the amount needed to fill the contact-lens-shaped cavity; d. mating the mold halves to form the contact-lens-shaped cavity filled with contact lens forming material and the annular cavity containing excess contact lens forming material; and e. curing the contact lens forming material to form a contact lens in the contact-lens-shaped cavity; the improvement comprising: f. before the step e. curing is completed, producing differential gas pressure across the openings in the annular cavity to substantially remove the excess lens forming material from the annular cavity.
Claim 2
Dependent Claim 175 words
In a process for molding both sides of a contact lens comprising the steps of: a. providing a first mold half having a convex lens molding surface; b. providing a second mold half having a concave lens molding surface, said mold halves being matable to form a contact-lens-shaped cavity and an annular cavity surrounding the contact-lens-shaped cavity, the annular cavity having at least two openings in fluid communication with the environment outside the mated mold halves; c. depositing lens forming material on the concave lens forming surface in excess of the amount needed to fill the contact-lens-shaped cavity; d. mating the mold halves to form the contact-lens-shaped cavity filled with contact lens forming material and the annular cavity containing excess contact lens forming material; and e. curing the contact lens forming material to form a contact lens in the contact-lens-shaped cavity; the improvement comprising: f. before the step e. curing is completed, producing differential gas pressure across the openings in the annular cavity to substantially remove the excess lens forming material from the annular cavity.
Claim 3
Dependent Claim 115 words
The process of claim 1 wherein the concave and convex lens molding surfaces have axes; the first mold half has a first structure extending substantially parallel to the axis of the convex lens molding surface; the second mold half has a second structure extending substantially parallel to the axis of the concave lens molding surface; when the mold halves are mated, the second structure is capable of enclosing at least part of the first structure and the annular cavity is located below the first and second structures; one of the openings in the annular cavity is space between the first and second structures; and the other opening is a hole in the second mold half.
Claim 4
Dependent Claim 28 words
The process of claim 2 wherein step f. is performed by pulling vacuum on the hole in the second mold structure from outside of the second mold half.
Claim 5
Dependent Claim 147 words
Apparatus for molding both sides of a contact lens comprising: a. a first mold half having a convex lens molding surface having a first axis and a first structure extending substantially parallel to said first axis; b. a second mold half having a concave lens molding surface having a second axis and a second structure extending substantially parallel to said second axis; said second structure being capable of enclosing at least part of said first structure, said mold halves being capable of mating to form a contact-lens-shaped cavity and an annular cavity having a bottom surrounding said contact-lens shaped cavity; and c. first and second openings in the annular cavity in fluid communication with the environment surrounding the mold halves when mated said first opening comprising space between the first and second structures and said second opening comprising a hole in the bottom of the annular cavity.
Claim 6
Dependent Claim 147 words
Apparatus for molding both sides of a contact lens comprising: a. a first mold half having a convex lens molding surface having a first axis and a first structure extending substantially parallel to said first axis; b. a second mold half having a concave lens molding surface having a second axis and a second structure extending substantially parallel to said second axis; said second structure being capable of enclosing at least part of said first structure, said mold halves being capable of mating to form a contact-lens-shaped cavity and an annular cavity having a bottom surrounding said contact-lens shaped cavity; and c. first and second openings in the annular cavity in fluid communication with the environment surrounding the mold halves when mated said first opening comprising space between the first and second structures and said second opening comprising a hole in the bottom of the annular cavity.
Claim 7
Dependent Claim 20 words
The apparatus of claim 4 further comprising means for producing differential gas pressure across the openings in the annular cavity.
Claim 8
Dependent Claim 26 words
The apparatus of claim 5 wherein the differential pressure means comprises a source of vacuum sealed over the hole in the bottom of the annular cavity.
Claim 9
Dependent Claim 60 words
The apparatus of claim 6 further comprising a support for the second mold half having an annular projection for holding an "O" ring and an opening within the annular projection connected to a vacuum source, said "O" ring capable of providing a gas tight seal against the second mold half surrounding the hole in the bottom of the annular cavity.
Claim 10
Dependent Claim 88 words
In apparatus for molding both sides of a contact lens comprising: a. a first mold half having a convex lens molding surface; b. a second mold half having a concave lens molding surface, said mold halves being matable to form a contact-lens-shaped cavity and an annular cavity surrounding the contact-lens-shaped cavity, the annular cavity having at least two openings in fluid communication with the environment outside of the mated mold halves; the improvement comprising: c. means for producing differential gas pressure across the openings in the annular cavity.
Claim 11
Dependent Claim 88 words
In apparatus for molding both sides of a contact lens comprising: a. a first mold half having a convex lens molding surface; b. a second mold half having a concave lens molding surface, said mold halves being matable to form a contact-lens-shaped cavity and an annular cavity surrounding the contact-lens-shaped cavity, the annular cavity having at least two openings in fluid communication with the environment outside of the mated mold halves; the improvement comprising: c. means for producing differential gas pressure across the openings in the annular cavity.

References Cited (Backward Citations)

US4197266A Cited
US4138086A Cited
US4680149A Cited
GB2226272A Cited
US5143660A Cited
EP0545720A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-05-30 1997-11-29 1998-05-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-05-30 2001-11-29 2002-05-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-05-30 2005-11-29 2006-05-31 $7700.00 Window Closed / Lapsed

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