Method and apparatus for fixing a metal block on a face of an ophthalmic lens, by casting molten metal thereon
US4852631A · kind A · utility
4Cited by
4References
1Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 25, 1988 |
| Grant date | Aug 1, 1989 |
| Priority date | — |
| Expiry date | Mar 25, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B13/0052
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
In this blocking apparatus, at least a portion of the pipe connecting the inlet orifice of the mold to the outlet orifice of the tank containing molten metal is in thermal contact with the mold, which mold includes at least one channel through which a cooling fluid can be caused to flow. Heater means are also associated with the pipe. Thus, the flow of molten metal from the tank into the mold can be stopped by allowing a plug of solidified metal to form in the pipe when the mold is cooled, and the flow of molten metal can be re-established by melting the plug of solidified metal by use of the heater means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.