Contact lens casting mould

• US 5,252,056 A
• Filed: 08/06/1992
• Issued: 10/12/1993
• Est. Priority Date: 03/16/1990
• Status: Expired due to Term

• Current Assignee: CIBA Vision Corporation (Bayer AG)
• Original Assignee: Ciba-Geigy Corporation (Novartis Ag)
• Inventors: Horner, Wilhelm, Hagmann, Peter, Hofer, Peter
• Primary Examiner(s): Nguyen, Khanh P.
• Application Number:
  US07/926,560
• Time in Patent Office: 432 Days
• Field of Search: 425/589, 425/595, 425/408, 425/412, 425/808, 425/403.1, 425/116, 425/555, 249/112, 249/121, 249/127, 249/134, 249/95, 249/163, 249/165, 249/167, 249/154, 249/82, 249/155, 264/2.2, 264/2.3, 264/328.7, 264/2.6, 264/2.7
• US Class Current: 425/555
• CPC Class Codes: B29C 33/202 Clamping means operating on closed or nearly closed mould parts, the clamping means being independently movable of the opening or closing means clamping devices for injection moulding machines B29C45/64
• CPC Class Codes: B29C 39/26 Moulds or cores
• CPC Class Codes: B29C 39/40 Compensating volume change, e.g. retraction in general B29C37/005
• CPC Class Codes: B29D 11/00057 characterised by the shape or surface condition of the edge, e.g. flashless, burrless, smooth
• CPC Class Codes: B29D 11/00509 to make toric lenses
• CPC Class Codes: B29D 11/00567 wherein the mould forms part of the final package for lenses
• CPC Class Codes: Y10S 425/808 Lens mold

Abstract

A contact lens casting mould includes two casting mould halves. A concave shaping surface (11) is constructed on a female part (1) and a convex shaping surface (21) on a male part (2). When joined together, the two casting mould halves (1 and 2) adhere by frictional connection.

Claims

1. A contact lens casting mould comprising two casting mould halves, a first of said mould halves being a female part having a concave shaping surface and a second of said mould halves being a male part having a convex shaping surface, wherein said shaping surfaces delimit a closed volume having a concave-convex and generally rotation symmetrical shape when the female part and the male part are joined together, said female part having a cylindrical body portion surrounding the concave shaping surface, a vertical outer wall of said cylindrical body portion having fixing elements thereon, and said male part being provided with a cylindrical projecting extension surrounding and projecting beyond said convex shaping surface, and wherein said female part and said male part are joined together, said fixing elements and said cylindrical projecting extension adhere to each other soley by frictional contact for assuring a tight fit of said male and female parts wherein said fixing elements are of vertical ribs.

2. A contact lens casting mould according to claim 1, wherein, in the joined state, the two casting mould halves (1 and 2) are in contact with each other along a line (42).

3. A contact lens casting mould according to claim 1, wherein the female part (1) and the male part (2) each have a flange-like projecting piece (12, 22) at a side thereof opposite the shaping surfaces (11 and 21, respectively).

4. A contact lens casting mould according to claim 3, wherein a protective cylinder (17) extends from the flange-like projecting piece (12) of the female part (1) and beyond the concave shaping surface (11).

5. A contact lens casting mould according to claim 2, wherein, adjoining the line of contact (42) of the casting mould halves (1 and 2), at least one channel (5) is provided which opens into an annular space (51) defined by the two casting mould halves (1 and 2).

6. A contact lens casting mould according to claim 1, wherein the casting mould halves are comprised of a thermoplastic material.

7. A contact lens casting mould according to claim 1, wherein the casting mould halves (1 or 2) have a thickness in the region of the shaping surfaces (11 or 21) of from approximately 0.5 mm to approximately 3 mm.

8. A contact lens casting mould according to claim 1, and further comprising a sealing cap (6) which detachably adheres to the female part by frictional connection.

9. A contact lens casting mould according to claim 8, wherein the sealing cap (6) is comprised of polypropylene.

10. A contact lens casting mould according to claim 1, wherein the female part (1) is sealed with a detachable foil.

11. A contact lens casting mould according to claim 7, wherein the thickness of the casting mould halves (1 or 2) in the region of the shaping surfaces (11 or 21) is approximately 1.5 mm.