# US 11,029,340 B2 · Detection apparatus, power receiving apparatus, non-contact power transmission system and detection method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,029,340 B2 - Document ID: US11029340B2 - Status: Granted - Kind: B2 - Application number: 16/430,523 - Filed: 2019-06-04 - Published: 2019-10-03 - Granted: 2021-06-08 - Earliest claimed: 2011-12-21 - Assignees: Sony Corporation - Applicants: Sony Corporation - Inventors: Shinji Komiyama - Web page: https://patentgrep.com/patent/US11029340B2 ## CPC - G01R 15/18: using inductive devices, e.g. transformers - G01R 21/006: {Measuring power factor} - G01V 3/10: using induction coils - G06F 17/00: Digital computing or data processing equipment or methods, specially adapted for specific functions (information retrieval, database structures or file system structures therefor G06F16/00) - H02J 4/00: Circuit arrangements for mains or distribution networks not specified as AC or DC; Circuit arrangements for mains or distribution networks combining AC and DC sections or sub-networks (arrangements using intermediate DC-AC-DC conversion H02J1/002; arrangements using high-voltage DC [HVDC] links H02J3/36) - H02J 7/42: with electronic devices having internal batteries, e.g. mobile phones - H02J 50/12: of the resonant type - H02J 50/60: responsive to the presence of foreign objects, e.g. detection of living beings - H02J 50/80: involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract Disclosed herein is a detection apparatus including: a resonant circuit provided with a Q-factor measurement coil and one or more capacitors to serve as a circuit for receiving pulses; a response-waveform detecting section configured to detect the waveform of a response output by the resonant circuit in response to the pulses; and a Q-factor measuring section configured to measure a Q factor of the resonant circuit from the response waveform detected by the response-waveform detecting section. It is possible to increase the precision of detection of a metallic foreign substance existing between a power transmitting side and a power receiving side. ## Claims ### Claim 1 A detection device comprising: determination circuitry; a pulse generator; and resonant circuitry including a coil and a capacitor and configured to receive the pulses from the pulse generator, wherein the determination circuitry is configured to detect a response waveform output from the resonance circuitry, to measure a quality factor of the coil based on the response waveform, and to determine whether the foreign object is present or not near the coil based on the measured quality factor and a reference quality factor. ### Claim 2 (depends on 1) The detection device according to claim 1, wherein the determination circuitry is configured to determine whether the foreign object is present or not near the coil based on a comparison result of the measured quality factor and the reference quality factor. ### Claim 3 (depends on 1) The detection device according to claim 1, wherein the reference quality factor is determined based on a quality factor when a power receiving apparatus is placed and there is no foreign object near the power receiving apparatus. ### Claim 4 (depends on 1) The detection device according to claim 1, wherein the determination circuitry is configured to measure a voltage across the capacitor to detect the response waveform. ### Claim 5 A power transmitting apparatus comprising: power transmitting circuitry configured to transmit electric power wirelessly to a power receiving apparatus; a pulse generator configured to generate pulses; resonant circuitry including a coil and a capacitor and configured to receive the pulses from the pulse generator; and determination circuitry configured to determine whether a foreign object is present or not near the coil, wherein the determination circuitry is configured to detect a response waveform output from the resonant circuitry in response to the pulses, to measure a quality factor of the coil based on the response waveform, and to determine whether the foreign object is present or not near the coil based on the measured quality factor and a reference quality factor. ### Claim 6 (depends on 5) The power transmitting apparatus according to claim 5, wherein the determination circuitry is configured to determine whether the foreign object is present or not near the coil based on a comparison result of the measured quality factor and the reference quality factor. ### Claim 7 (depends on 5) The power transmitting apparatus according to claim 5, wherein the reference quality factor is determined based on a quality factor when the power receiving apparatus is placed and there is no foreign object near the power receiving apparatus. ### Claim 8 (depends on 5) The power transmitting apparatus according to claim 5, wherein the determination circuitry is configured to measure a voltage across the capacitor to detect the response waveform. ### Claim 9 (depends on 5) The power transmitting apparatus according to claim 5, wherein the power transmitting circuitry includes a power transmitting resonant circuitry including a power transmitting coil. ### Claim 10 (depends on 5) The power transmitting apparatus according to claim 5, wherein the power transmitting circuitry is configured to stop transmitting electric power wirelessly to the power receiving apparatus when the determination circuitry determines that the foreign object is present near the coil.