# US 11,309,859 B2 · Noise filter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,309,859 B2 - Document ID: US11309859B2 - Status: Granted - Kind: B2 - Application number: 17/257,378 - Filed: 2019-07-05 - Published: 2021-09-02 - Granted: 2022-04-19 - Earliest claimed: 2018-07-17 - Assignees: Kabushiki Kaisha Toyota Chuo Kenkyusho - Applicants: Kabushiki Kaisha Toyota Chuo Kenkyusho - Inventors: Atsuhiro Takahashi; Katsuya Nomura; Takashi Kojima - Web page: https://patentgrep.com/patent/US11309859B2 ## CPC - H03H 1/0007: {of radio frequency interference filters} - H03H 7/06: including resistors (H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence) - H01F 17/06: with core substantially closed in itself, e.g. toroid - H02M 1/12: Arrangements for reducing harmonics from AC input or output - H02M 1/14: Arrangements for reducing ripples from DC input or output - H03H 7/0115: {comprising only inductors and capacitors (H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence)} - H03H 7/0123: {comprising distributed impedance elements together with lumped impedance elements} - H03H 7/09: Filters comprising mutual inductance - H01F 2017/065: {Core mounted around conductor to absorb noise, e.g. EMI filter} - H02M 1/126: {using passive filters} - H02M 1/44: Circuits or arrangements for compensating for electromagnetic interference in converters or inverters - H03H 2001/005: {Wound, ring or feed-through type inductor} - H03H 2001/0057: {comprising magnetic material} - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) ## Abstract A noise filter may include: a first conductive line extending between an input and an output terminal portion, wherein the first conductive line includes an input-side conductive line extending between the input terminal portion and a branch portion, and an output-side conductive line extending between the output terminal portion and the branch portion; a second conductive line connected to the branch portion of the first conductive line, wherein a capacitor is on the second conductive line; and a magnetic body surrounding at least a part of a circumference of at least a part of the first conductive line, wherein the magnetic body is configured to magnetically couple the input-side and the output-side conductive lines such that at least an equivalent series inductance of the capacitor and a parasitic inductance of the second conductive line are reduced by a mutual inductance between the input-side conductive line and the output-side conductive line. ## Claims ### Claim 1 A noise filter comprising: a first conductive line extending between an input terminal portion and an output terminal portion, the first conductive line including: an input-side conductive line extending between the input terminal portion and a branch portion; and an output-side conductive line extending between the output terminal portion and the branch portion; a second conductive line connected to the branch portion of the first conductive line, wherein a capacitor is on the second conductive line; and a first magnetic body surrounding at least a part of a circumference of at least a part of the first conductive line, the first magnetic body being configured to magnetically couple the input-side conductive line to the output-side conductive line such that at least an equivalent series inductance of the capacitor and a parasitic inductance of the second conductive line are reduced by a mutual inductance between the input-side conductive line and the output-side conductive line, the first magnetic body comprising: a first magnetic body portion surrounding at least a part of a circumference of a first portion that is at least a part of the input-side conductive line; a second magnetic body portion surrounding at least a part of a circumference of a second portion that is at least a part of the output-side conductive line; and a third magnetic body portion extending between the first magnetic body portion and the second magnetic body portion, the third magnetic body portion being configured to adjust a coupling coefficient between the input-side conductive line and the output-side conductive line. ### Claim 2 (depends on 1) The noise filter according to claim 1, wherein, the first portion of the input-side conductive line does not include a coil, and the second portion of the output-side conductive line does not include a coil. ### Claim 3 (depends on 1) The noise filter according to claim 1, wherein the first portion of the input-side conductive line and the second portion of the output-side conductive line extend to be linearly aligned, and the first magnetic body is arranged to cross the first conductive line above the branch portion and surround the at least a part of the circumference of the first portion and the at least a part of the circumference of the second portion. ### Claim 4 (depends on 3) The noise filter according to claim 3, wherein the first magnetic body is configured of a combination of a first lower divided portion, a second lower divided portion, a first upper divided portion, and a second upper divided portion, the first lower divided portion extends below the first portion of the input-side conductive line to cross the input-side conductive line, the second lower divided portion extends below the second portion of the output-side conductive line to cross the output-side conductive line, the first upper divided portion crosses the first conductive line above the branch portion and extends between one end of the first lower divided portion and one end of the second lower divided portion, the second upper divided portion crosses the first conductive line above the branch portion and extends between another end of the first lower divided portion and another end of the second lower divided portion, and the first upper divided portion and the second upper divided portion are skew above the branch portion. ### Claim 5 (depends on 1) The noise filter according to claim 1, wherein the first portion of the input-side conductive line and the second portion of the output-side conductive line face each other with an interval of a predetermined distance therebetween and extend substantially parallel with each other, and the first magnetic body is arranged to loop outside the first portion and the second portion. ### Claim 6 (depends on 5) The noise filter according to claim 5, wherein the first magnetic body is configured of a combination of a first divided portion and a second divided portion, and a gap is provided between at least one end of the first divided portion and at least one end of the second divided portion. ### Claim 7 (depends on 6) The noise filter according to claim 6, wherein each of the first divided portion and the second divided portion has a U-shape. ### Claim 8 (depends on 1) The noise filter according to claim 1, wherein the first magnetic body is arranged to spiral around the first conductive line. ### Claim 9 (depends on 1) The noise filter according to claim 1, wherein the first conductive line is configured of a flat plate-shaped bus bar. ### Claim 10 (depends on 1) The noise filter according to claim 1, further comprising a second magnetic body surrounding at least a part of a circumference of at least a part of the second conductive line. ### Claim 11 (depends on 10) The noise filter according to claim 10, wherein the first magnetic body and the second magnetic body are constituted of a same magnetic material. ### Claim 12 (depends on 1) The noise filter according to claim 1, further comprising a resistor disposed on the second conductive line and connected to the capacitor in series.