# US 10,374,459 B2 · Wireless power transfer using multiple coil arrays > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,459 B2 - Document ID: US10374459B2 - Status: Granted - Kind: B2 - Application number: 15/082,533 - Filed: 2016-03-28 - Published: 2016-09-29 - Granted: 2019-08-06 - Earliest claimed: 2015-03-29 - Assignees: Chargedge, Inc. - Applicants: ChargEdge, Inc. - Inventors: Sanjaya Maniktala - Web page: https://patentgrep.com/patent/US10374459B2 ## CPC - H02J 50/12: of the resonant type - H02J 50/40: using two or more transmitting or receiving devices (H02J50/50 takes precedence) - H02J 50/70: involving the reduction of electric, magnetic or electromagnetic leakage fields - H01F 27/36: Electric or magnetic shields or screens (movable for varying inductance H01F21/10) - H01F 38/14: Inductive couplings - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES ## Abstract In one embodiment of a wireless power transmitter, two coils are magnetically coupled together by placing both coils on a magnetic layer. A power circuit generates an AC signal of a defined voltage magnitude that causes a current to flow through the first coil, which generates a magnetic field having a first polarity. The second coil is coupled to the first coil. Current flows through the second coil and generates a magnetic field having a second polarity that is opposite from the first polarity. Because the magnetic field generated by each coil has a different polarity, the magnetic fields attract and form a strong magnetic field that flows from the first coil to the second coil. The strong magnetic field can transfer greater amounts of power to a receiver in comparison to coil configurations that emit magnetic fields in the same direction that repel one another. ## Claims ### Claim 1 A wireless power device comprising: a first coil configured to receive a time-varying current that flows in the first coil in a first direction to produce a magnetic field having a first polarity; a second coil coupled to the first coil in such a way that the time-varying current flows in the second coil in a second direction to produce a magnetic field having a second polarity; and a first substantially planar layer of magnetic material configured to magnetically couple the first coil with the second coil, wherein a central axis of the first coil is normal to a surface of the first substantially planar layer of magnetic material and a central axis of the second coil is normal to the surface of the first substantially planar layer of magnetic material. ### Claim 2 (depends on 1) The wireless power device of claim 1, wherein the first coil is coupled in series with the second coil. ### Claim 3 (depends on 1) The wireless power device of claim 1, wherein the first coil is coupled in parallel with the second coil. ### Claim 4 (depends on 1) The wireless power device of claim 1, wherein the first coil and the second coil have an equal number of turns, substantially the same shape, and substantially the same area. ### Claim 5 (depends on 1) The wireless power device of claim 1, further comprising a power source configured to generate the time-varying current, wherein the first coil is configured to receive the time-varying current from the power source. ### Claim 6 (depends on 5) The wireless power device of claim 5, further comprising a capacitor coupled between the power source and the first coil. ### Claim 7 (depends on 1) The wireless power device of claim 1, further comprising a receive circuit coupled to the first coil and the second coil, wherein the receive circuit is configured to generate a voltage from the time-varying current that flows in the first coil and the second coil. ### Claim 8 (depends on 1) The wireless power device of claim 1, further comprising: a third coil configured to receive a second time-varying current that flows in the third coil in a third direction; a fourth coil coupled to the third coil in such a way that the second time-varying current flows in the fourth coil in a fourth direction, wherein the third direction is opposite from the fourth direction; a second substantially planar layer of magnetic material configured to magnetically couple the third coil and the fourth coil, wherein a central axis of the third coil is normal to a surface of the second substantially planar layer of magnetic material and a central axis of the fourth coil is normal to the surface of the second substantially planar layer of magnetic material; and an air gap separating the first substantially planar layer of magnetic material from the second substantially planar layer of magnetic material. ### Claim 9 (depends on 8) The wireless power device of claim 8, wherein the third coil is coupled in series with the fourth coil. ### Claim 10 (depends on 8) The wireless power device of claim 8, wherein the third coil is coupled in parallel with the fourth coil. ### Claim 11 (depends on 8) The wireless power device of claim 8, wherein the third coil and the fourth coil have an equal number of turns, substantially the same shape, and substantially the same area. ### Claim 12 (depends on 8) The wireless power device of claim 8, further comprising a power source configured to generate the second time-varying current and the third coil is configured to receive the second time-varying current from the power source. ### Claim 13 (depends on 8) The wireless power device of claim 8, wherein the third coil is coupled to the second coil in such a way that the first time-varying current that flows in the second coil is the same direction as the second time-varying current that flows in the third coil. ### Claim 14 A wireless power device comprising: a power source configured to generate a first time-varying current; a first coil configured to receive the first time-varying current from the power source, wherein the first time-varying current flows in the first coil in a first direction; a second coil coupled to the first coil in such a way that the first time-varying current flows in the second coil in a second direction, wherein the first direction is opposite from the second direction; a third coil configured to receive a second time-varying current, wherein the time varying current flows in the third coil in a third direction and the third direction is opposite from the second direction; a fourth coil coupled to the third coil in such a way that the second time-varying current flows in the fourth coil in a fourth direction, wherein the fourth direction is opposite from the third direction and the first direction; a substantially planar layer of magnetic material configured to magnetically couple the first coil and the second coil, and to magnetically couple the third coil and the fourth coil; and an air gap in the substantially planar layer of magnetic material, wherein the air gap magnetically isolates the first coil from the third coil and magnetically isolates the second coil from the fourth coil, wherein a central axis of each of the first coil, second coil, third coil, and fourth coil is normal to a surface of the substantially planar layer of magnetic material. ### Claim 15 (depends on 14) The wireless power device of claim 14, wherein the first coil is coupled in series with the second coil. ### Claim 16 (depends on 14) The wireless power device of claim 14, wherein the first coil is coupled in parallel with the second coil. ### Claim 17 (depends on 14) The wireless power device of claim 14, wherein the third coil is coupled in series with the fourth coil. ### Claim 18 (depends on 14) The wireless power device of claim 14, wherein the third coil is coupled in parallel with the fourth coil. ### Claim 19 (depends on 14) The wireless power device of claim 14, wherein the first coil and the second coil have an equal number of turns, substantially the same shape, and substantially the same area. ### Claim 20 (depends on 14) The wireless power device of claim 14, wherein the third coil and the fourth coil have an equal number of turns, substantially the same shape, and substantially the same area. ### Claim 21 (depends on 14) The wireless power device of claim 14, wherein the power source is configured to generate the second time-varying current and the third coil is configured to receive the second time-varying current from the power source. ### Claim 22 (depends on 14) The wireless power device of claim 14, wherein the third coil is coupled to the second coil in such a way that the first time-varying current that flows in the second coil is the same as the second time-varying current that flows in the third coil. ### Claim 23 (depends on 14) The wireless power device of claim 14, further comprising a capacitor coupled between the first coil and the power source. ### Claim 24 A wireless power device comprising: a first coil wound in a first direction such that the first coil is configured to generate a first magnetic field having a first polarity; a second coil coupled to the first coil, wherein the second coil is wound in a second direction and is configured to generate a second magnetic field having a second polarity, wherein the first polarity is opposite from the second polarity; and a substantially planar layer of magnetic material configured to magnetically couple the first coil with the second coil, wherein a central axis of the first coil is normal to a surface of the substantially planar layer of magnetic material and a central axis of the second coil is normal to the surface of the substantially planar layer of magnetic material. ### Claim 25 (depends on 24) The wireless power device of claim 24, wherein the first coil is coupled in series with the second coil. ### Claim 26 (depends on 24) The wireless power device of claim 24, wherein the first coil is coupled in parallel with the second coil. ### Claim 27 (depends on 24) The wireless power device of claim 24, wherein the first coil and the second coil have an equal number of turns, substantially the same shape, and substantially the same area. ### Claim 28 (depends on 24) The wireless power device of claim 24, further comprising a power source coupled to the first coil, the power source configured to generate a time-varying current. ### Claim 29 (depends on 28) The wireless power device of claim 28, further comprising a capacitor coupled between the power source and the first coil. ### Claim 30 (depends on 24) The wireless power device of claim 24, further comprising a receive circuit coupled to the first coil and the second coil, wherein the receive circuit is configured to generate a voltage from a time-varying current flowing in the first coil and the second coil.