Circuit for detecting a utensil load placed asymmetrically relative to an induction heating coil
US4447691A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 1980 |
| Grant date | May 8, 1984 |
| Priority date | — |
| Expiry date | Jul 30, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S99/14
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A plurality of magnetic field sensors are mounted adjacent the periphery of an induction heating coil of flat, spiral configuration which is energized by ultrasonic frequency energy to generate a time-varying magnetic field. The magnetic field sensors are connected in a ciruit to produce an output signal when a magnetic utensil load is placed asymmetrically with respect to the center of the induction heating coil. In response to sensor output exceeding a predetermined value a warning indication is provided. The ultrasonic energy level is reduced in response to the warning indication to minimize radio interference which would otherwise occur due to leakage magnetic flux.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.