Electrostatic shield for a transformer
US4379999A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1981 |
| Grant date | Apr 12, 1983 |
| Priority date | — |
| Expiry date | Oct 30, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F27/36
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrostatic shield for an electrical transformer comprises a substantially ring-shaped inner insulator of asymmetric vertical cross-section with a side confronting a coil of the transformer being substantially planar and the remaining surface being of a curved section, a field concentration relaxation conductor formed from a conductive foil, completely surrounding the inner insulator, and a multiple outer insulator comprising at least one layer of polyethylene terephthalate (PET) film and at least one mica insulation layer with mica bonded to a non-conductive backing film such as glass tape or PET film by a bonding agent such as epoxy resin, whereby the dielectric strength of the electrostatic shield and hence the transformer, is substantially improved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.