Patent · US Expired

Device for protecting metal objects situated in the environment of an intense magnetic field developed by an alternator rotor without a stator

US4489218A · kind A · utility

1Cited by
3References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 12, 1982
Grant dateDec 18, 1984
Priority date
Expiry dateAug 12, 2002

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05K9/00
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The protection device comprises two half cages (13, 14) superposed on each other and surrounding the rotor (8) under test. The half cages together constitute a cage with openings between its bars and provided with water cooling in said bars. The cage ensures that the magnetic field generated by a rotor under test with excitation current is stopped within a distance equivalent to the size of the holes between the cage bars. Induced current heating in the cage is kept under control by water cooling, and metal objects outside the cage are substantially protected from the magnetic field by the cage. Air can pass freely through the cage, and the rotor can be observed without removing the cage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.