Magnetic alignment systems with NFC for electronic devices
A magnetic alignment system can include a primary annular magnetic alignment component and a secondary annular magnetic alignment component. The primary alignment component can include an inner annular region having a first magnetic orientation, an outer annular region having a second magnetic orientation opposite to the first magnetic orientation, and a non-magnetized central annular region disposed between the primary inner annular region and the primary outer annular region. The secondary alignment component can have a magnetic orientation with a radial component. Additional features, such as a rotational magnetic alignment component and/or an NFC coil and circuitry can be included.
1. A wireless charging device comprising:
a housing having a charging surface;
an inductive coil disposed within the housing and having an axis normal to the charging surface, the inductive coil being configured to transfer power wirelessly through the charging surface;
an annular magnetic alignment component disposed within the housing coaxial with and outboard of the inductive coil, the annular magnetic alignment component including a plurality of sectors, each sector including one or more arcuate magnets, each arcuate magnet comprising:
an inner arcuate region having a magnetic polarity oriented in a first axial direction;
an outer arcuate region having a magnetic polarity oriented in a second axial direction opposite the first axial direction; and
a non-magnetized central arcuate region disposed between the inner arcuate region and the outer arcuate region; and
a near-field communication (NFC) coil disposed within the housing, outboard of the inductive coil, and coaxial with the inductive coil, the NFC coil configured to wirelessly exchange signals with an NFC coil of a portable device through the charging surface.
2. The wireless charging device of claim 1 further comprising:
an annular magnetic shield disposed at a distal surface of the annular magnetic alignment component.
3. The wireless charging device of claim 1 wherein the NFC coil is coupled to an NFC tag circuit.
4. The wireless charging device of claim 1 wherein the NFC coil is positioned between the inductive coil and the annular magnetic alignment component.
5. The wireless charging device of claim 1 wherein the first axial direction has a south magnetic pole toward the charging surface.
6. The wireless charging device of claim 1 wherein the first axial direction is the same direction for all of the sectors.
7. The wireless charging device of claim 1 wherein alternating sectors have opposite first axial directions.
8. The wireless charging device of claim 1 wherein the annular magnetic alignment component includes a gap between two of the sectors.
9. The wireless charging device of claim 8 wherein an electrically conductive path connected to the inductive coil passes through the gap.
10. An accessory device comprising:
a housing having an interface surface;
an annular magnetic alignment component disposed within the housing and having an axis normal to the interface surface, the annular magnetic alignment component including a plurality of sectors, each sector comprising:
an inner arcuate region having a magnetic polarity oriented in a first axial direction;
an outer arcuate region having a magnetic polarity oriented in a second axial direction opposite the first axial direction; and
a non-magnetized central arcuate region disposed between the inner arcuate region and the outer arcuate region; and
a near-field communication (NFC) coil disposed within the housing and coaxial with the annular magnetic alignment component, the NFC coil configured to wirelessly exchange signals with another device through the interface surface.
11. The accessory device of claim 10 wherein the NFC coil is coupled to an NFC tag circuit.
12. The accessory device of claim 10 wherein the NFC coil is positioned inboard of the annular magnetic alignment component.
13. The accessory device of claim 10 wherein the NFC coil is positioned outboard of the annular magnetic alignment component.