Magnetic Alignment Systems for Wireless Power Devices

Patent metadata

Field	Value
Publication number	US-2022311286-A1
Application number	US-202217669929-A
Country	US
Kind code	A1
Filing date	Feb 11, 2022
Priority date	Mar 26, 2021
Publication date	Sep 29, 2022
Grant date	—

Abstract

Power may be transmitted wirelessly between electronic devices. Devices such as cellular telephones, wireless charging pucks, and other equipment may have wireless power circuitry with coils. The wireless power circuitry may have inverter circuitry and rectifier circuitry. The inverter circuitry and a coil that receives alternating-current signals from the inverter circuitry may be used to transmit wireless power signals. Wireless power signals received by a coil in a mated device may be rectified using the rectifier circuitry in that device to produce direct-current power. To align first and second devices for power transfer between their coils, devices may be provided with alignment magnets. The alignment magnets may be configured to permit a first device to be mated back-to-back with a second device such as a second device of the same type as the first device.

First claim

What is claimed is:

1 . A wireless power device configured to pair with external equipment that has an external equipment coil, the wireless power device comprising:
a housing; wireless power circuitry including a wireless power coil; and alignment magnets that are configured to align the external equipment coil to the wireless power coil, wherein poles of the alignment magnets are located in pole positions, wherein the pole positions exhibit reflection symmetry about an axis, and wherein each pole at a given pole position has a magnetic polarity that is opposite to that of the pole located in a pole position corresponding to the given pole position reflected about the axis.

2 . The wireless power device of claim 1 wherein the wireless power device has a front and rear and wherein the alignment magnets are configured to align the external equipment coil to the wireless power coil at the rear.

3 . The wireless power device of claim 2 wherein the rear lies in a plane and wherein the axis is parallel to the plane.

4 . The wireless power device of claim 3 wherein the axis comprises a longitudinal axis along which the housing is elongated.

5 . The wireless power device of claim 4 wherein the housing comprises a cellular telephone housing and wherein the external equipment coil comprises an additional wireless power coil.

6 . The wireless power device of claim 3 wherein the alignment magnets each have north and south poles lying in the plane.

7 . The wireless power device of claim 6 wherein the alignment magnets are arranged in a ring surrounding a center.

8 . The wireless power device of claim 7 wherein each alignment magnet in the ring has a respective magnetic axis that runs through the center.

9 . The wireless power device of claim 8 wherein the ring of alignment magnets has an outer ring of poles that alternate as a function of angle around a center of the outer ring and has an inner ring of poles that alternate as a function of angle around the center.

10 . The wireless power device of claim 9 wherein the housing comprises an electronic device housing of a given model of device and wherein the external equipment is of the same given model of device.

11 . The wireless power device of claim 9 wherein the alignment magnets are configured to allow the external equipment to mate with the alignment magnets with rotation multiples of 90° or less about the center of the wireless power coil.

12 . The wireless power device of claim 11 wherein the alignment magnets are configured to allow the external equipment to mate with the alignment magnets with rotation multiples of 45° or less about the center of the wireless power coil.

13 . The wireless power device of claim 9 wherein the wireless power circuitry comprises inverter circuitry configured to supply alternating-current signals to the wireless power coil and comprises rectifier circuitry configured to rectify alternating-current signals from the wireless power coil.

14 . The wireless power device of claim 9 wherein the external equipment comprises additional alignment magnets, wherein the alignment magnets are configured to mate with the additional alignment magnets, wherein the additional alignment magnets have additional alignment magnet poles, wherein the additional alignment magnet poles are located in additional alignment magnet pole positions, wherein the additional alignment magnet pole positions exhibit reflection symmetry about an additional axis, and wherein each additional alignment magnet pole at a given additional alignment magnet pole position has a magnetic polarity that is opposite to that of the additional alignment magnet pole located in an additional alignment magnet pole position corresponding to the given additional alignment magnet pole position reflected about the additional axis.

15 . The wireless power device of claim 10 wherein the wireless power coil has a center and wherein the alignment magnets are configured to allow only a finite set of discrete rotational orientations between the external equipment and the housing about the center in which the external equipment coil is aligned with the wireless power coil.

16 . The wireless power device of claim 15 wherein the external equipment comprises a cellular telephone and wherein the housing comprises a cellular telephone housing.

17 . The wireless power device defined in claim 16 wherein the alignment magnets are configured to allow the external equipment to mate with the alignment magnets with rotation multiples of 22.5° about the center of the wireless power coil.

18 . The wireless power device defined in claim 16 wherein the alignment magnets are configured to allow the external equipment to mate with the alignment magnets with rotation multiples of 90° about the center of the wireless power coil.

19 . A wireless power device of a given model configured to receive wireless power from an external device of the same given model while mated back-to-back with the external device, comprising:
wireless power circuitry; a housing having a back surface and a front surface; and magnetic alignment structures configured to align the external device to the housing at the back surface in a back-to-back configuration in which a back housing surface of the external device faces the back surface.

20 . The wireless power device of claim 19 wherein the wireless power circuitry comprises a coil, wherein the housing comprises a cellular telephone housing, wherein the external device comprises a cellular telephone, and wherein the magnetic alignment structures are configured to attract the cellular telephone housing against the back housing surface of the external device while wireless power is being received by the coil.

21 . The wireless power device of claim 20 wherein the wireless power circuitry comprises inverter circuitry configured to supply alternating-current signals to the coil and comprises rectifier circuitry configured to rectify alternating-current signals from the coil.

22 . The wireless power device of claim 21 wherein the alignment magnets are configured to allow the external equipment to mate back-to-back with the cellular telephone housing at angular rotation multiples of 22.5° around a center of the coil.

23 . A wireless charging puck operable with portable electronic devices of a given model, comprising:
a housing having first and second opposing sides; wireless power circuitry including at least one coil, wherein the wireless power circuitry is configured to transmit wireless power signals through the first and second sides; and a ring of alignment magnets configured to mate with a first of the portable electronic devices of the given model on the first side while simultaneously mating with a second of the portable electronic devices of the given model on the second side.

24 . The wireless charging puck of claim 23 wherein the ring of alignment magnets comprises a plurality of magnets that each have a magnetic pole axis parallel to a surface normal of the first side.

25 . The wireless power device of claim 24 wherein the alignment magnets are configured to:
allow the first of the portable electronic devices to mate with the housing at angular rotation multiples of 90° or less about the center; and
allow the second of the portable electronic devices to mate with the housing at angular rotation multiples of 90° or less about th

Assignees

• Apple Inc

Inventors

• Schwartz Adam L

Classifications

• H02J7/731

  specially adapted for holding portable devices containing batteries (H02J7/751 takes precedence) · CPC title

• H02J50/005

  Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices · CPC title

• H02J50/90 Primary

  involving detection or optimisation of position, e.g. alignment · CPC title

• H02J50/10

  using inductive coupling · CPC title

• H02J7/0044

  Electricity · mapped topic