Hollow jewelry ring having inner round design
US5916271A · kind A · utility
Inventor
Key dates
| Filing date | Dec 5, 1997 |
| Grant date | Jun 29, 1999 |
| Priority date | — |
| Expiry date | Dec 5, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22D25/026
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A hollow or partially hollow jewelry ring having inner round design formed by investment casting method. The method comprises producing a first mold having an inner cavity shaped in accordance with the external shape of the article to be produced. A second mold is produced for forming a wax core insert which is inserted in the first mold cavity for forming the hollow region of the articles The second mold has an inner cavity formed in the shape of, but slightly smaller than, the external shape of the article. The cavity of the second mold has holes which form spacer pins on the wax core insert. The wax core insert is then placed in the cavity of the first mold and is maintained in a precise, predetermined position by the spacer pins. During waxing of the article, a plastiwax is introduced into and fills the cavity of the first mold, completely surrounding the wax core insert. The plastiwax hardens and is removed from the first mold cavity with the wax core insert. The wax core insert is then removed from the plastiwax article by suitable water soluble or chemical means to form a hollow plastiwax article which is a replica of the desired metal articles. The plastiwax replica is then…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.