Machine and method for an automated filling of a mold assembly for molding an ophthalmic lens

Patent metadata

Field	Value
Publication number	US-10926496-B2
Application number	US-201415108533-A
Country	US
Kind code	B2
Filing date	Dec 23, 2014
Priority date	Dec 27, 2013
Publication date	Feb 23, 2021
Grant date	Feb 23, 2021

Abstract

The present disclosure relates to a machine for an automated filling of a mold assembly for molding an ophthalmic lens, comprising: filling means to fill the mold assembly with a molding material through a filling aperture provided in the mold assembly, acquiring means to acquire an input value linked to the internal volume of the mold assembly, and control means for controlling the flow rate of molding material injected by the filling means in the mold assembly according to a flow rate profile deduced as a function of said input value.

First claim

The invention claimed is:

1. A machine for an automated filling of a mold assembly for molding an ophthalmic lens, the machine comprising:
filling means to fill the mold assembly with a molding material through a filling aperture provided in the mold assembly;
acquiring means to acquire an input value linked to the internal volume of the mold assembly; and
control means for controlling a flow rate of molding material injected by the filling means in the mold assembly according to a flow rate profile determined as a function of said input value;
wherein the acquiring means comprises scanning means suitable to scan an edge of the mold assembly for determining the width of said filling aperture, determining an internal face is convex, and determining a position of the internal face of the mold assembly which is convex, and
wherein a microcontroller is programmed to control the position of a nozzle of the filling means as a function of the determined position of said internal face in order to position said nozzle relative to said convex internal face.

2. The machine according to claim 1 , wherein said input value is the width of the filling aperture, measured between two molding shells of the mold assembly.

3. The machine according to claim 1 , suitable for filling a batch of several mold assemblies having essentially a same internal volume, wherein the control means is configured for:
controlling the flow rate of molding material injected in a first mold assembly according to a learning flow rate profile that is determined as a function of the measured input value;
when the first mold assembly is completely filled, acquiring a measured value that is relative to the internal volume of the first mold assembly; and
filling the other mold assemblies of the batch according to a flow rate profile determined as a function of said measured value.

4. The machine according claim 3 , further comprising:
the microcontroller;
wherein:
said microcontroller is programmed to control the position of said nozzle to position said nozzle relative to said convex internal face such that the molding material falling from the filling means runs as much as possible down this convex internal face; and
said measured value is the duration of the filling of the first mold assembly.

5. The machine according to claim 1 , wherein the flow rate profile comprises at least a first flow rate level and a second flow rate level determined as a function of said input value, said first flow rate level being greater than said second flow rate level.

6. The machine according to claim 4 , wherein:
the flow rate profile comprising at least a first flow rate level and a second flow rate level determined as a function of said input value, said first flow rate level being greater than said second flow rate level, and
said measured value is the duration of the filling of the first mold assembly, and
a duration of the first flow rate level is determined by the control means as a function of said measured value and said input value.

7. The machine according to claim 1 , further comprising:
detecting means for detecting a complete filling of the mold assembly and for sending a signal to the control means when the mold assembly is completely filled, the control means being configured to stop the injection of molding material based said signal received from the detecting means.

8. The machine according to claim 7 , wherein the control means is further configured for positioning the detecting means and the filling means relative to each other as a function of said input value, along an axis present in a plan representative of the filling aperture and along an axis perpendicular to said plane.

9. The machine according to claim 7 , wherein the detecting means comprises:
a vacuum pump with a vacuum nozzle positioned and configured to suck an amount of excess molding material out of the mold assembly; and
a sensor suitable for measuring a pressure in said vacuum nozzle.

10. The machine according to claim 1 , wherein:
the filling means comprises a pump suitable for displacing the molding material from a storage tank to an output nozzle,
the control means is further configured for controlling the pump,
a pinch valve is configured to apply pressure on a pipe connecting the pump and the output nozzle, and
the control means is further configured for controlling the pinch valve so that the pinch valve applies pressure against the pipe during the filling of the mold assembly and the pinch valve releases the pressure on the pipe based on the mold assembly being completely filled.

11. The machine according to claim 1 , wherein:
the mold assembly comprises two molding shells and an annular closure adhesive tape disposed at the periphery of the molding shells,
closing means are provided with a pusher configured to push an end of the adhesive tape to close the filling aperture,
the control means is further configured for controlling the position of the pusher, and
the closing means comprises a vacuum suction device configured to suck an excess amount of molding material pushed out by the adhesive tape while closing the filling aperture.

12. The machine according to claim 1 , wherein, after having acquired said input value, the control means is further configured for searching in a database registry for a record associated to said input value, and if no corresponding record is found, creating a new record associated with said input value and containing a flow rate profile.

13. The machine according to claim 1 , wherein said control means is further configured for positioning the nozzle of the filling means.

14. The machine according to claim 3 , wherein the learning flow rate profile exhibits mainly a single constant value.

15. The machine according to claim 5 , wherein the flow rate profile includes in the following order a ramp-up to initiate the filling of the mold assembly, a first flow rate level, an intermediate ramp-down, a second flow rate level, and a final ramp-down to end the flow and thus end the filling of the mold assembly.

16. The machine according to claim 6 , wherein the flow rate profile includes in the following order a ramp-up to initiate the filling of the mold assembly, a first flow rate level, an intermediate ramp-down, a second flow rate level, and a final ramp-down to end the flow and thus end the filling of the mold assembly.

17. The machine according to claim 6 , wherein durations of any ramp-up and of any ramp-down are determined by the control means as a function of said input value.

18. The machine according to claim 8 , wherein the control means is further configured for positioning the detecting means and the filling means relative to each other and to the filling aperture as a function of said input value.

19. A system for filling of a mold assembly for molding an ophthalmic lens, the system comprising:
scanning means suitable to scan an edge of the mold assembly for detecting an internal face of the mold assembly as being convex;
means for positioning a nozzle at a location based on the detected convex internal face and with respect to a filling aperture of the mold assembly, said nozzle being positioned relative to said convex internal face;
means for filling the mold assembly with a molding material through a filling aperture provided in the mold assembly; and
means for controlling a flow rate of molding material injected by the means for filling into a cavity of the mold assembly.

20. A system for filling of a mo

Assignees

• Essilor Int

Inventors

• Acda Amparo
• Maruthanont Ratchapoom
• Homwongs Chatree

Classifications

• G05B15/02

  electric · CPC title

• G02C7/022

  Ophthalmic lenses having special refractive features achieved by special materials or material structures (G02C7/049 takes precedence) · CPC title

• B29L2011/0016

  Lenses · CPC title

• B29K2995/0026

  Transparent · CPC title

• B29D11/00951

  Measuring, controlling or regulating · CPC title