Method and device for cleaning deposited material from a molding surface of a mold for forming ophthalmic lenses

Patent metadata

Field	Value
Publication number	US-10035177-B2
Application number	US-201514960604-A
Country	US
Kind code	B2
Filing date	Dec 7, 2015
Priority date	Dec 8, 2014
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

A method of cleaning deposited material from a molding surface ( 10 ) of a mold ( 1 ) for forming ophthalmic lenses, including bringing a cleaning head ( 20 ) into contact with the molding surface ( 10 ), the rotational axis ( 22 ) of the cleaning head ( 20 ) being arranged normal to the molding surface ( 10 ), rotating ( 220 ) the cleaning head ( 20 ) around the rotational axis ( 22 ) while maintaining the contact between the cleaning head ( 20 ) and the molding surface ( 10 ), moving the cleaning head ( 20 ) to perform a precession motion ( 110 ) around a central normal ( 11 ) on the molding surface ( 10 ), while rotating ( 220 ) the cleaning head ( 20 ) around the rotational axis ( 22 ) and while maintaining the contact between the cleaning head ( 20 ) and the molding surface ( 10 ). During the precession motion ( 110 ) the rotational axis ( 22 ) includes an inclination angle (α 1,α2 ) with the central normal ( 11 ) on the molding surface ( 10 ).

First claim

The invention claimed is:

1. A Method of cleaning deposited material from a molding surface ( 10 ) of a mold ( 1 ) for forming ophthalmic lenses, the method comprising the steps of:
cleaning deposited material from a molding surface by bringing a cleaning head ( 20 ) having a rotational axis ( 22 ) into contact with the molding surface ( 10 ), the rotational axis ( 22 ) of the cleaning head ( 20 ) being arranged normal to the molding surface ( 10 ),
rotating ( 220 ) the cleaning head ( 20 ) around the rotational axis ( 22 ) while maintaining the contact between the cleaning head ( 20 ) and the molding surface ( 10 ),
moving the cleaning head ( 20 ) to perform a precession motion ( 110 ) around a central normal ( 11 ) on the molding surface ( 10 ) running through an apex of the molding surface thereof, while rotating ( 220 ) the cleaning head ( 20 ) around the rotational axis ( 22 ) and while maintaining the contact between the cleaning head ( 20 ) and the molding surface ( 10 ),

wherein during the precession motion ( 110 ) the rotational axis ( 22 ) of the cleaning head ( 20 ) includes an inclination angle (α 1 ,α 2 ) with the central normal ( 11 ) on the molding surface ( 10 ).

2. The method according to claim 1 , wherein the inclination angle (α 1 ,α 2 ) is in a range of up to about 40°.

3. The method according to claim 1 , wherein while being in contact with the molding surface, ( 10 ) the cleaning head ( 20 ) is pressed against the molding surface ( 10 ) using a force (F) in a range of about 10 N to about 20 N.

4. The method according to claim 1 , wherein the cleaning head ( 20 ) is made of silicone or of a foamed material.

5. The method according to claim 1 , wherein the cleaning head ( 20 ) is covered with a cloth ( 23 ).

6. The method according to claim 1 , wherein the cleaning head ( 20 ) has a concave or convex shape matching a convex or concave shape of the molding surface ( 10 ).

7. The method according to claim 1 , further comprising the step of dispensing an amount of up to about 300 μl of a cleaning liquid ( 40 ) onto the molding surface ( 10 ).

8. The method according to claim 1 , wherein the cleaning head ( 20 ) is moved to perform the precession motion ( 110 ) with a rotational speed of about 10 revolutions per minute to about 300 revolutions per minute around the central normal ( 11 ) on the molding surface ( 10 ), and wherein the cleaning head ( 20 ) is rotated around its rotational axis ( 22 ) with a rotational speed of about 10 revolutions per minute to about 300 revolutions per minute.

9. The method according to claim 1 , wherein the molding surface ( 10 ) is a convex molding surface, and wherein cleaning of the convex molding surface is started at the inclination angle (α 1 ,α 2 ) of about 25°, and wherein the inclination angle (α 1 ,α 2 ) is then decreased stepwise until the rotational axis ( 22 ) of the cleaning head and the central normal ( 11 ) on the molding surface ( 10 ) coincide.

10. The method according to claim 1 , wherein the molding surface ( 10 ) is a concave molding surface, and wherein cleaning of the concave molding surface is started with the rotational axis ( 22 ) of the cleaning head ( 20 ) and the central normal ( 11 ) on the molding surface ( 10 ) coinciding, and wherein the inclination angle (α 1 , α 2 ) is then increased stepwise, up to an inclination angle (α 1 , α 2 ) of about 35°.

11. The method according to claim 2 , wherein the inclination angle (α 1 ,α 2 ) is in a range of up to about 35° for a male mold and up to about 25° for a female mold.

12. The method according to claim 7 , wherein the amount of cleaning liquid ( 40 ) is about 50 μl to about 200 μl for a female mold and an amount of about 150 μl to about 300 μl for a male mold ( 10 ).

13. The method according to claim 8 , wherein the cleaning head ( 20 ) is moved to perform the precession motion ( 110 ) with a rotational speed of about 10 revolutions per minute to about 100 revolutions per minute around the central normal ( 11 ) on the molding surface ( 10 ), and wherein the cleaning head ( 20 ) is rotated around its rotational axis ( 22 ) with a rotational speed of about 50 revolutions per minute to about 300 revolutions per minute.

14. The method according to claim 13 , wherein the cleaning head ( 20 ) is moved to perform the precession motion ( 110 ) with a rotational speed of about 100 revolutions per minute around the central normal ( 11 ) on the molding surface ( 10 ), and wherein the cleaning head ( 20 ) is rotated around its rotational axis ( 22 ) with a rotational speed of about 110 revolutions per minute.

Assignees

• Novartis Ag

Inventors

• Cocora Gabriela
• Heidrich Halina
• Kern Fabian
• Heinrich Axel
• Lanig Volker

Classifications

• B08B9/00

  Cleaning hollow articles by methods or apparatus specially adapted thereto · CPC title

• B29D11/00519

  Reusable moulds · CPC title

• B29D11/00125

  Auxiliary operations, e.g. removing oxygen from the mould, conveying moulds from a storage to the production line in an inert atmosphere · CPC title

• B29D11/00432

  Auxiliary operations, e.g. machines for filling the moulds (B29D11/00125 takes precedence) · CPC title

• B08B1/006 Primary

  Operations & Transport · mapped topic