Reshaping a glass lens blank suspended on a flow of gas
US5281249A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 1993 |
| Grant date | Jan 25, 1994 |
| Priority date | — |
| Expiry date | Jun 1, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B23/035
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for imparting a predetermined contour to an ophthalmic glass lens. The method comprises positioning a forming manifold in the base of a reshaping chamber, the upper surface of the manifold having a surface contour that is the reverse of the bottom contour surface of the reshaped lens, positioning the lens blank in the chamber, heating the lens blank to a temperature at which the blank deforms, and establishing a continuous, lateral flow of gas on the upper surface of the forming manifold whereby the glass is supported while it sags to the desired shape. The apparatus comprises a reshaping chamber, a source of heat to bring a lens blank to its deforming temperature, a forming manifold having an upper surface contour that is the reverse of the desired contour on the lower surface of the reshaped lens blank, and means to supply a continuous, lateral flow of gas on the upper surface of the manifold whereby the glass blank is supported while it deforms to the desired shape.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.