Auto-dimming apparatus for controlling power delivered to a load
US7952301B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Dec 12, 2008 |
| Grant date | May 31, 2011 |
| Priority date | — |
| Expiry date | Dec 3, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/391
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit with a magnetically variable inductor that is placed in close proximity to an independently wound control coil and connected in parallel to a current transformer having primary and secondary windings wound on a magnetic core wherein the transformer core with associated windings. The inductor core is placed within the bore of the control coil and an optional focusing armature concentrates the magnetic field at the poles. Application of a control current forms poles at the control coil extremities and causes a change in magnetic properties of the inductor core thereby altering the power output of the current transformer inversely to the magnitude of the control current. The control current from the output of the secondary coil of a current transformer in series with the load and conditioned by a feedback conditioning circuit modulates the level of the control current. The magnetically variable inductor controls a D.C. to A.C. power inverter circuit, which is useful in supplying power to a fluorescent lamp and other A.C. receptive loads connected to the output of an inverting circuit. Additionally, a microprocessor optionally modulates the feedback from the secondary of the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.