Mold unit for molding ophthalmic lenses

Patent metadata

Field	Value
Publication number	US-12589564-B2
Application number	US-202117455139-A
Country	US
Kind code	B2
Filing date	Nov 16, 2021
Priority date	Nov 17, 2020
Publication date	Mar 31, 2026
Grant date	Mar 31, 2026

Abstract

A mold unit for molding ophthalmic lenses comprises:
A) an adapter piece comprising an opening extending around a longitudinal axis; B) a sleeve fixedly connected to the adapter piece and extending through the opening of the adapter piece; C) a lens mold rigidly mounted to the sleeve; D) an adjustment ring firmly attached to the sleeve to circumferentially surround a portion of the sleeve. The adjustment ring comprises a flat circular outer engagement surface, and the adapter piece comprises at least one clamping block having a flat inner clamping surface. The flat inner clamping surface frictionally clamps the flat circular outer engagement surface to prevent inadvertent rotation of the sleeve relative to the adapter piece) but to allow rotation of the sleeve relative to the adapter piece upon the application of a torque higher than a predetermined threshold torque.

First claim

The invention claimed is:

1 . Mold unit ( 22 ) for molding ophthalmic lenses, the mold unit ( 22 ) comprising:
an adapter piece ( 220 ) for insertion into a compartment ( 20 ) of a lens mold carrier ( 2 ), the adapter piece comprising an opening ( 2200 ) extending around a longitudinal axis ( 2201 ); a sleeve ( 221 ) fixedly connected to the adapter piece ( 220 ) and extending along the longitudinal axis ( 2201 ) through the opening ( 2200 ) of the adapter piece ( 220 ); a lens mold ( 222 ) rigidly mounted to the sleeve ( 221 ); an adjustment ring ( 224 ) firmly attached to the sleeve ( 221 ) and mounted to the sleeve ( 221 ) in a manner such as to circumferentially surround a portion of the sleeve ( 221 );
wherein the adjustment ring ( 224 ) comprises a circularly curved smooth non-toothed outer engagement surface ( 2244 ) facing radially outwardly and extending in a circumferential direction around the sleeve ( 221 ), and wherein the adapter piece ( 220 ) comprises at least one clamping block ( 2211 ) having a circularly curved smooth non-toothed inner clamping surface ( 2214 ) facing radially inwardly towards the circularly curved smooth non-toothed outer engagement surface ( 2244 ) of the adjustment ring ( 224 ), the at least one clamping block ( 2211 ) being arranged such that the circularly curved smooth non-toothed inner clamping surface ( 2214 ) of the clamping block ( 2211 ) frictionally clamps the circularly curved smooth non-toothed outer engagement surface ( 2244 ) of the adjustment ring ( 224 ) so as to prevent inadvertent rotation of the sleeve ( 221 ) relative to the adapter piece ( 220 ) but to allow rotation of the sleeve ( 221 ) relative to the adapter piece ( 220 ) upon the application of a torque to the sleeve ( 221 ) which is higher than a predetermined threshold torque in the range of 0.3 Nm to 0.6 Nm.

2 . Mold unit according to claim 1 , wherein the adapter piece ( 220 ) comprises two clamping blocks ( 2211 ), each of the two clamping blocks ( 2211 ) having the circularly curved smooth non-toothed inner clamping surface ( 2214 ) facing radially inwardly towards the circularly curved smooth non-toothed outer engagement surface ( 2244 ) of the adjustment ring ( 224 ), the two clamping blocks ( 2211 ) being symmetrically arranged relative to the longitudinal axis ( 2201 ) at radially opposite sides of a circularly curved smooth non-toothed outer surface adjustment ring ( 224 ).

3 . Mold unit according to claim 2 , wherein the circularly curved smooth non-toothed inner clamping surface ( 2214 ) of each of the two clamping blocks ( 2211 ) is circular and extends in the circumferential direction, with a curvature of the circularly curved smooth non-toothed inner clamping surface ( 2214 ) of each of the two clamping blocks ( 2211 ) corresponding to the curvature of the circularly curved smooth non-toothed outer engagement surface ( 2244 ) of the adjustment ring ( 224 ), and wherein an inner diameter ( 2215 ) between the circularly curved smooth non-toothed inner clamping surfaces ( 2214 ) of each of the two clamping blocks ( 2211 ) is smaller than an outer diameter ( 2245 ) of the circularly curved smooth non-toothed outer engagement surface ( 2244 ) of the adjustment ring ( 224 ).

4 . Mold unit according to claim 3 , wherein the area of the circularly curved smooth non-toothed inner clamping surface ( 2214 ) of each of the two clamping blocks ( 2211 ) is in the range of 15 mm 2 to 25 mm 2 .

5 . Mold unit according to claim 1 , wherein the adjustment ring ( 224 ) is composed of two ring parts ( 2240 , 2241 ) which are assembled in a form-locked manner to form the adjustment ring ( 224 ).

6 . Mold unit according to claim 3 , wherein the circularly curved smooth non-toothed inner clamping surfaces ( 2214 ) are provided with a chamfer ( 2216 ) at an axial end thereof for simplifying introduction of the adjustment ring ( 224 ) firmly mounted to the sleeve ( 221 ) between the circularly curved smooth non-toothed inner clamping surfaces ( 2214 ) of the two clamping blocks ( 2211 ) during assembly of the mold unit.

7 . Mold unit according to claim 3 , wherein the clamping blocks ( 2211 ) are made of polyoxymethylene, and wherein the adjustment ring ( 224 ) is made of polyketone.

8 . Mold unit according to claim 3 , wherein the inner diameter ( 2215 ) between the circularly curved smooth non-toothed inner clamping surfaces ( 2214 ) of the two clamping blocks ( 2211 ) is 0.6 mm-1.2 mm smaller than the outer diameter ( 2245 ) of the circularly curved smooth non-toothed outer engagement surface ( 2244 ) of the adjustment ring ( 224 ).

9 . Mold unit according to claim 1 , wherein the lens mold ( 222 ) has a lens molding surface that is not rotationally symmetrical.

10 . Mold unit according to claim 1 , wherein the sleeve ( 221 ) comprises engagement surfaces ( 2220 ) for an adjustment tool for rotating the sleeve ( 221 ) in the circumferential direction to a desired angular position.

11 . Mold unit according to claim 1 , wherein the lens mold ( 222 ) rigidly mounted to the sleeve ( 221 ) is a male mold having a toric lens molding surface.

Assignees

• Alcon Inc

Inventors

• Stutz Michael
• Bernard Jan
• Campanelli Giovanni
• Lomb Lukas
• Schwab Matthias

Classifications

• B29C33/305

  Mounting of moulds or mould support plates (handling of moulds B29C31/006; mounting of moulds for injection moulding B29C45/1742) · CPC title

• B29C33/306

  Exchangeable mould parts, e.g. cassette moulds, mould inserts (moulds with exchangeable mould parts for injection moulding B29C45/2673; mounting of exchangeable mould inserts for injection moulding B29C45/2675) · CPC title

• B29D11/00509

  to make toric lenses · CPC title

• B29D11/00259

  Plants for the production of contact lenses · CPC title

• B29D11/0048 Primary

  Moulds for lenses (moulds for plastic articles in general B29C33/00) · CPC title