Free positioning charging pad
US11171502B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 2019 |
| Grant date | Nov 9, 2021 |
| Priority date | — |
| Expiry date | Sep 25, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K1/181
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Systems, methods and apparatus for wireless charging are disclosed. An apparatus has a wireless charging apparatus has a battery charging power source coupled to a charging circuit, a plurality of charging cells configured to provide a charging surface, and a controller. The controller may be configured to provide a pulse to the charging circuit, detect a frequency of oscillation of the charging circuit responsive to the pulse or a rate of decay of the oscillation of the charging circuit, and determine that a chargeable device has been placed in proximity to a coil of the charging circuit based on changes in a characteristic of the charging circuit. The pulse may have a duration that is less than half the period of a nominal resonant frequency of the charging circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.