# US 2018/0323655 A1 · Power transmission device, power reception device, and wireless power supply system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0323655 A1 - Document ID: US20180323655A1 - Status: Published application - Kind: A1 - Application number: 16/039,002 - Filed: 2018-07-18 - Published: 2018-11-08 - Earliest claimed: 2016-03-18 - Assignees: Murata Manufacturing Co., Ltd. - Applicants: Murata Manufacturing Co., Ltd. - Inventors: Tatsuya HOSOTANI - Web page: https://patentgrep.com/patent/US20180323655A1 ## CPC - H02J 50/12: of the resonant type - H01F 27/28: Coils; Windings; Conductive connections - H01F 38/14: Inductive couplings - H02J 50/70: involving the reduction of electric, magnetic or electromagnetic leakage fields - 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 A power transmission circuit is connected to a power transmission coil having a coil aperture. The power transmission circuit includes a conductive or magnetic power-transmission-coil near member opposed to the coil aperture of the power transmission coil, and a repeating coil arranged on a side opposite to a side on which the power-transmission-coil near member is arranged with respect to the power transmission coil and coupled to the power transmission coil at least via a magnetic field. When a shortest distance between the power transmission coil and the power-transmission-coil near member is expressed as (dt1) and a shortest distance between the power transmission coil and the repeating coil is expressed as (dt2), dt2≤dt1. ## Claims ### Claim 1 A power transmission device in a wireless power supply system in which high-frequency power is wirelessly provided from the power transmission device to a power reception device, the power transmission device including a power transmission coil, the power reception device including a power reception coil at least magnetic-field coupled to the power transmission coil, and the power transmission coil having a coil aperture, the power transmission device comprising: a power transmission circuit connected to the power transmission coil; a conductive or magnetic power-transmission-coil near member opposed to the coil aperture of the power transmission coil and having a planar or curved surface portion, an eddy current caused by a magnetic field based on an operation of the wireless power supply system being allowed to flow in the power-transmission-coil near member; and a repeating coil arranged on a side opposite to a side on which the power-transmission-coil near member is arranged with respect to the power transmission coil and coupled to the power transmission coil at least via a magnetic field, wherein when a shortest distance between the power transmission coil and the power-transmission-coil near member is expressed as dt1 and a shortest distance between the power transmission coil and the repeating coil is expressed as dt2, dt2≤dt1. ### Claim 2 A power transmission device in a wireless power supply system in which high-frequency power is wirelessly provided from the power transmission device to a power reception device, the power transmission device including a power transmission coil, the power reception device including a power reception coil at least magnetic-field coupled to the power transmission coil, and the power transmission coil having a coil aperture, the power transmission device comprising: a power transmission circuit connected to the power transmission coil; a casing housing the power transmission coil and having an inner surface opposed to the coil aperture of the power transmission coil and an outer surface on a back side of the inner surface; and a repeating coil arranged on a side opposite to the inner surface of the casing with respect to the power transmission coil and coupled to the power transmission coil at least via a magnetic field, wherein when a shortest distance between the power transmission coil and the outer surface of the casing is expressed as dt1′ and a shortest distance between the power transmission coil and the repeating coil is expressed as dt2, dt2≤dt1′. ### Claim 3 (depends on 1) The power transmission device according to claim 1, further comprising a resonance capacitor connected to the repeating coil and constituting a resonance circuit together with the repeating coil. ### Claim 4 (depends on 3) The power transmission device according to claim 3, wherein a resonance frequency of the resonance circuit is equal to a frequency of an alternating magnetic field formed from the power transmission coil. ### Claim 5 (depends on 2) The power transmission device according to claim 2, further comprising a resonance capacitor connected to the repeating coil and constituting a resonance circuit together with the repeating coil. ### Claim 6 A power reception device in a wireless power supply system in which high-frequency power is wirelessly provided from a power transmission device to the power reception device, the power transmission device including a power transmission coil, the power reception coil including a power reception coil at least magnetic-field coupled to the power transmission coil, and the power reception coil having a coil aperture, the power reception device comprising: a power reception circuit connected to the power reception coil; a conductive or magnetic power-reception-coil near member opposed to the coil aperture of the power reception coil and having a planar or curved surface portion, an eddy current caused by a magnetic field based on an operation of the wireless power supply system being allowed to flow in the power-reception-coil near member; and a repeating coil arranged on a side opposite to a side on which the power-reception-coil near member is arranged with respect to the power reception coil and coupled to the power reception coil at least via a magnetic field, wherein when a shortest distance between the power reception coil and the power-reception-coil near member is expressed as dr1 and a shortest distance between the power reception coil and the repeating coil is expressed as dr2, dr2≤dr1. ### Claim 7 A power reception device in a wireless power supply system in which high-frequency power is wirelessly provided from a power transmission device to the power reception device, the power transmission device including a power transmission coil, the power reception coil including a power reception coil at least magnetic-field coupled to the power transmission coil, and the power reception coil having a coil aperture, the power reception device comprising: a power reception circuit connected to the power reception coil; a casing housing the power reception coil and having an inner surface opposed to the coil aperture of the power reception coil and an outer surface on a back side of the inner surface; and a repeating coil arranged on a side opposite to the inner surface of the casing with respect to the power reception coil and coupled to the power reception coil at least via a magnetic field, wherein when a distance between the power reception coil and the outer surface of the casing is expressed as dr1′ and a distance between the power reception coil and the repeating coil is expressed as dr2, dr2≤dr1′. ### Claim 8 (depends on 6) The power reception device according to claim 6, further comprising a resonance capacitor connected to the repeating coil and constituting a resonance circuit together with the repeating coil. ### Claim 9 (depends on 8) The power reception device according to claim 8, wherein a resonance frequency of the resonance circuit is equal to a frequency of an alternating magnetic field formed from the power transmission coil. ### Claim 10 (depends on 7) The power reception device according to claim 7, further comprising a resonance capacitor connected to the repeating coil and constituting a resonance circuit together with the repeating coil. ### Claim 11 A wireless power supply system in which high-frequency power is wirelessly provided from a power transmission device to a power reception device, the power transmission device including a power transmission coil, the power reception device including a power reception coil at least magnetic-field coupled to the power transmission coil, the power transmission coil having a coil aperture, and the power transmission device including a power transmission circuit connected to the power transmission coil, a conductive or magnetic power-transmission-coil near member opposed to the coil aperture of the power transmission coil and having a planar or curved surface portion, an eddy current caused by a magnetic field based on an operation of the wireless power supply system being allowed to flow in the power-transmission-coil near member, and a repeating coil arranged on a side opposite to a side on which the power-transmission-coil near member is arranged with respect to the power transmission coil and coupled to the power transmission coil at least via a magnetic field, wherein when a distance between the power transmission coil and the power-transmission-coil near member is expressed as dt1 and a distance between the power transmission coil and the repeating coil is expressed as dt2, dt2≤dt1. ### Claim 12 A wireless power supply system in which high-frequency power is wirelessly provided from a power transmission device to a power reception device, the power transmission device including a power transmission coil, the power reception device including a power reception coil at least magnetic-field coupled to the power transmission coil, the power transmission coil having a coil aperture, and the power transmission device including a power transmission circuit connected to the power transmission coil, a casing housing the power transmission coil and having an inner surface opposed to the coil aperture of the power transmission coil and an outer surface on a back side of the inner surface, and a repeating coil arranged on a side opposite to the inner surface of the casing with respect to the power transmission coil and coupled to the power transmission coil at least via a magnetic field, wherein when a distance between the power transmission coil and the outer surface of the casing is expressed as dt1′ and a distance between the power transmission coil and the repeating coil is expressed as dt2, dt2≤dt1′. ### Claim 13 (depends on 11) The wireless power supply system according to claim 11, wherein, where an ordinal number is expressed as n-th (n is an integer greater than or equal to one), when the repeating coil includes an n-th repeating coil and an (n+1)-th repeating coil positioned farther from the power transmission coil than the n-th repeating coil, and a distance from the n-th repeating coil to the (n+1)-th repeating coil is expressed as dt(n+2) and a distance from an (n−1)-th repeating coil positioned nearer the power transmission coil than the n-th repeating coil to the n-th repeating coil or a distance from the power transmission coil to the n-th repeating coil is expressed as dt(n+1), dt(n+2)≤dt(n+1). ### Claim 14 (depends on 12) The wireless power supply system according to claim 12, wherein, where an ordinal number is expressed as n-th (n is an integer greater than or equal to one), when the repeating coil includes an n-th repeating coil and an (n+1)-th repeating coil positioned farther from the power transmission coil than the n-th repeating coil, and a distance from the n-th repeating coil to the (n+1)-th repeating coil is expressed as dt(n+2) and a distance from an (n−1)-th repeating coil positioned nearer the power transmission coil than the n-th repeating coil to the n-th repeating coil or a distance from the power transmission coil to the n-th repeating coil is expressed as dt(n+1), dt(n+2)≤dt(n+1). ### Claim 15 A wireless power supply system in which high-frequency power is wirelessly provided from a power transmission device to a power reception device, the power transmission device including a power transmission coil, the power reception device including a power reception coil at least magnetic-field coupled to the power transmission coil, the power reception coil having a coil aperture, the power reception device including a power reception circuit connected to the power transmission coil, a conductive or magnetic power-reception-coil near member opposed to the coil aperture of the power reception coil and having a planar or curved surface portion, an eddy current caused by a magnetic field based on an operation of the wireless power supply system being allowed to flow in the power-reception-coil near member, and a repeating coil arranged on a side opposite to a side on which the power-reception-coil near member is arranged with respect to the power reception coil and coupled to the power reception coil at least via a magnetic field, wherein when a distance between the power reception coil and the power-reception-coil near member is expressed as dr1 and a distance between the power reception coil and the repeating coil is expressed as dr2, dr2≤dr1. ### Claim 16 A wireless power supply system in which high-frequency power is wirelessly provided from a power transmission device to a power reception device, the power transmission device including a power transmission coil, the power reception device including a power reception coil at least magnetic-field coupled to the power transmission coil, the power reception coil having a coil aperture, and the power reception device including a power reception circuit connected to the power transmission coil, a casing housing the power reception coil and having an inner surface opposed to the coil aperture of the power reception coil and an outer surface on a back side of the inner surface, and a repeating coil arranged on a side opposite to the inner surface of the casing with respect to the power reception coil and coupled to the power reception coil at least via a magnetic field, wherein when a distance between the power reception coil and the outer surface of the casing is expressed as dr1′ and a distance between the power reception coil and the repeating coil is expressed as dr2, dr2≤dr1′. ### Claim 17 (depends on 11) The wireless power supply system according to claim 11, further comprising a resonance capacitor connected to the repeating coil and constituting a resonance circuit together with the repeating coil. ### Claim 18 (depends on 12) The wireless power supply system according to claim 12, further comprising a resonance capacitor connected to the repeating coil and constituting a resonance circuit together with the repeating coil. ### Claim 19 (depends on 15) The wireless power supply system according to claim 15, further comprising a resonance capacitor connected to the repeating coil and constituting a resonance circuit together with the repeating coil. ### Claim 20 (depends on 17) The wireless power supply system according to claim 17, wherein a resonance frequency of the resonance circuit is equal to a frequency of an alternating magnetic field formed from the power transmission coil.