Coreless induction furnace
US4238637A · kind A · utility
Inventors
Key dates
| Filing date | Jul 25, 1978 |
| Grant date | Dec 9, 1980 |
| Priority date | — |
| Expiry date | Jul 25, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B6/34
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for reducing surface perturbations of a molten metal in an inductive furnace wherein the molten metal is contained in a crucible surrounded by two groups of coils, each connected to a polyphase system of voltages. In the first group of coils, the inverse component of the voltages are negligible with respect to the direct components and the ratio of the homopolar component to the direct component is selected so that the tangential components of the vortices generated by the homopolar and direct components have opposing signs and amplitudes of the same order of magnitude. In the second group of coils, the voltages have a direct component negligible with respect to the inverse components and the ratio of the homopolar component to the inverse component is selected so that the tangential components of the vortices generated by the homopolar and inverse components have opposing signs and amplitudes of the same order of magnitude.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.