Doughnut-type transformer for resistance butt welding
US4297665A · kind A · utility
Inventors
Key dates
| Filing date | May 14, 1980 |
| Grant date | Oct 27, 1981 |
| Priority date | — |
| Expiry date | May 14, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F30/16
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The doughnut-type transformer comprises a spirally wound core consisting of several individual annular cores each tightened by rod members. The annular core is surrounded by transformer sections comprising the primary and the secondary windings. Each winding is composed of turns shaped as sectors in the plane of the transformer cross-section, a cooled turn of the secondary winding being placed between the turns of the primary winding in each transformer section. The turns of the windings surround the annular core so that the geometric center of each winding is displaced from the geometric center of the annular core in the cross-sectional plane thereof and the geometric center of the annular core is farther from the transformer axis. Each turn of the secondary winding is provided with a passage for cooling water to circulate therethrough, which water being supplied and discharged through one and the same contact ring and is first cooling one half of the whole number of the transformer sections and then the other half.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.