Current restriction element responsive to applied voltage
US4484251A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 1982 |
| Grant date | Nov 20, 1984 |
| Priority date | — |
| Expiry date | Sep 20, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01C7/115
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A current restriction device for alternate circuit with small size, low producing cost and low power loss has been found by using a ferro-electric body with rectangular hysterisis characteristics. Said device is used for instance as a ballast for restricting current in a fluorescent lamp. Said ferro-electric body has main component of B.sub.a T.sub.i O.sub.3, additive of S.sub.r or P.sub.b for substitution of part of B.sub.a and Z.sub.n or S.sub.n for substitution of part of T.sub.i, and a mineralizer of M.sub.n o or C.sub.r2 O.sub.3. The voltage-current characteristics of said ferro-electric body show non-linearity that the impedance ratio (Z.sub.2 /Z.sub.1) of the impedance Z.sub.2 measured with alternate field of 500 volts/mm to the impedance Z.sub.1 measured with alternate field of 5 volts/mm is less than 1/10.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.