# US 11,441,783 B2 · Induction heating type cooktop having improved use convenience > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,441,783 B2 - Document ID: US11441783B2 - Status: Granted - Kind: B2 - Application number: 16/558,039 - Filed: 2019-08-31 - Published: 2020-03-05 - Granted: 2022-09-13 - Earliest claimed: 2018-08-31 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Wontae Kim; Seongho Son; Jaekyung Yang; Yongsoo Lee; Hyunwoo Jun - Web page: https://patentgrep.com/patent/US11441783B2 ## CPC - F24C 7/087: {of electric circuits regulating heat} - H05B 3/748: {Resistive heating elements, i.e. heating elements exposed to the air, e.g. coil wire heater (H05B3/742 takes precedence)} - H05B 6/105: {using a susceptor} - H05B 6/1209: {induction cooking plates or the like and devices to be used in combination with them} - H05B 6/1263: {using coil cooling arrangements} - F24C: DOMESTIC STOVES OR RANGES (exclusively for solid fuels F24B); DETAILS OF DOMESTIC STOVES OR RANGES, OF GENERAL APPLICATION - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract An induction heating type cooktop includes a case, a cover plate that is coupled to an upper end of the case and that includes an upper plate configured to seat an object on an upper surface of the upper plate, a working coil disposed in the case and configured to heat the object, a thin film attached on the upper plate, and a thermal insulating member disposed vertically between a lower surface of the upper plate and the working coil. ## Claims ### Claim 1 An induction heating type cooktop, comprising: a case; a cover plate coupled to an upper end of the case, the cover plate comprising an upper plate configured to seat an object on an upper surface of the upper plate; a working coil disposed in the case and configured to heat the object; a thin film attached on the upper plate, the thin film having an electrical resistance value to be heated by induction by the working coil; and a thermal insulating member disposed vertically between a lower surface of the upper plate and the working coil, wherein a skin depth of the thin film is greater than a thickness of the thin film, and wherein the working coil is configured to: based on a magnetic object being placed on the upper surface of the upper plate, heat the magnetic object by an eddy current induced in the magnetic object by a magnetic field of the working coil passing through a surface of the thin film, and based on a non-magnetic object being placed on the upper surface of the upper plate, heat the thin film by an eddy current induced in the thin film by the magnetic field to thereby heat the non-magnetic object by the heated thin film. ### Claim 2 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film is coated on the upper surface of the upper plate or a lower surface of the upper plate. ### Claim 3 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film is made of a conductive material and has a magnetic property. ### Claim 4 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film is made of a conductive material and has a non-magnetic property. ### Claim 5 (depends on 1) The induction heating type cooktop of claim 1, wherein a thickness of the thin film is between 0.1 μm and 1,000 μm. ### Claim 6 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film is configured to, based on the magnetic object being placed on the upper surface of the upper plate, define an equivalent circuit comprising (i) a resistance component and an inductor component of the magnetic object and (ii) a resistance component and an inductor component of the thin film. ### Claim 7 (depends on 6) The induction heating type cooktop of claim 6, wherein an electrical impedance defined by the resistance component and the inductor component of the magnetic object in the equivalent circuit is less than an electrical impedance defined by the resistance component and the inductor component of the thin film. ### Claim 8 (depends on 7) The induction heating type cooktop of claim 7, wherein a magnitude of the eddy current induced in the magnetic object is greater than a magnitude of the eddy current induced in the thin film. ### Claim 9 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film has an electrical impedance, and the non-magnetic object does not have an electrical impedance. ### Claim 10 (depends on 9) The induction heating type cooktop of claim 9, wherein the eddy current induced in the thin film is not applied to the non-magnetic object. ### Claim 11 (depends on 1) The induction heating type cooktop of claim 1, further comprising: a shielding plate disposed at a lower surface of the working coil and configured to block the magnetic field generated vertically below the working coil based on the working coil being driven; a support member disposed between a lower surface of the shielding plate and a lower surface of the case and configured to support the shielding plate upward; and a cooling fan disposed inside the case and configured to cool the working coil. ### Claim 12 (depends on 11) The induction heating type cooktop of claim 11, wherein the support member comprises an elastic body configured to support the shielding plate upward. ### Claim 13 (depends on 11) The induction heating type cooktop of claim 11, wherein the cooling fan is configured to: draw external air from an outside of the case and transfer the drawn external air toward the working coil; or draw internal air from an inside of the case and discharge the drawn internal air toward the outside of the case, and wherein the thermal insulating member is configured to block heat transfer, to the working coil, from the object or the thin film heated based on the working coil being driven. ### Claim 14 (depends on 6) The induction heating type cooktop of claim 6, wherein the resistance component and the inductor component of the magnetic object in the equivalent circuit are connected to each other electrically in series, and wherein the resistance component and the inductor component of the thin film in the equivalent circuit are connected to each other electrically in series, and wherein the resistance component and the inductor component of the thin film in the equivalent circuit are connected to the resistance component and the inductor component of the magnetic object electrically in parallel. ### Claim 15 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film is configured to contact the object placed on the upper surface of the upper plate. ### Claim 16 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film is configured to, based on the non-magnetic object being placed on the upper surface of the upper plate, define an equivalent circuit comprising a resistance component and an inductor component of the thin film. ### Claim 17 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film is located vertically above the working coil at a position corresponding to the working coil, and wherein the thin film has a predetermined thickness that enables the thin film to be inductively heated by the working coil. ### Claim 18 (depends on 1) The induction heating type cooktop of claim 1, wherein the thin film has a ring shape comprising a plurality of concentric circles having different diameters. ### Claim 19 (depends on 1) The induction heating type cooktop of claim 1, further comprising: a plurality of working coils disposed in the case and spaced apart from one another, the plurality of working coils including the working coil; and a plurality of thin films attached to the upper plate and spaced apart from one another, the plurality of thin films including the thin film, wherein each of the plurality of thin films is positioned vertically above at a position corresponding to one of the plurality of working coils.