# US 11,310,874 B2 · Induction cooktop with improved magnetic flux concentrating foil > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,310,874 B2 - Document ID: US11310874B2 - Status: Granted - Kind: B2 - Application number: 16/356,194 - Filed: 2019-03-18 - Published: 2019-09-26 - Granted: 2022-04-19 - Earliest claimed: 2018-03-23 - Assignees: Whirlpool Corporation - Applicants: Whirlpool Corporation - Inventors: Davide Parachini; Cristiano Vito Pastore - Web page: https://patentgrep.com/patent/US11310874B2 ## CPC - H05B 6/1254: {using conductive pieces to direct the induced magnetic field} - H05B 6/065: {using coordinated control of multiple induction coils} - H05B 6/1272: {with more than one coil or coil segment per heating zone} - H05B 6/1281: {with flat coils} - H05B 2206/02: Induction heating - H05B 2206/022: Special supports for the induction coils - H05B 2213/03: Heating plates made out of a matrix of heating elements that can define heating areas adapted to cookware randomly placed on the heating plate - Y02B 40/00: Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract An induction cooking apparatus includes a plurality of induction coils arranged in an array. The induction coils include conductive windings and at least one foil. The at least one foil includes magnetically permeable material extending beneath the plurality of induction coils. ## Claims ### Claim 1 An induction cooking apparatus comprising: a plurality of induction coils arranged in an array, the induction coils comprising conductive windings; at least one foil comprising magnetically permeable material extending beneath the plurality of induction coils, wherein the at least one foil defines at least one foil aperture extending through the at least one foil; and an electrical circuit in communication with each of the plurality of induction coils via at least one conductor disposed in the at least one foil aperture. ### Claim 2 (depends on 1) The induction cooking apparatus according to claim 1, wherein the electrical circuit is configured to receive control signals from a controller, wherein the controller is configured to control the plurality of induction coils. ### Claim 3 (depends on 1) The induction cooking apparatus according to claim 1, wherein the induction coils comprise a coil former keyed with the at least one foil aperture to linearly align the induction coils. ### Claim 4 (depends on 3) The induction cooking apparatus according to claim 3, wherein the magnetically permeable material comprises a combination of a magnetically permeable material and a polymeric material forming the at least one foil. ### Claim 5 (depends on 1) The induction cooking apparatus according to claim 1, wherein the at least one foil comprises a first magnetic foil and a second magnetic foil in a stacked configuration. ### Claim 6 (depends on 1) The induction cooking apparatus according to claim 1, wherein the at least one foil comprises a soft magnetic material in the form of ferrite powder. ### Claim 7 (depends on 1) The induction cooking apparatus according to claim 1, wherein the at least one foil forms a mat having a substantially uniform thickness and is configured to concentrate magnetic flux generated by the plurality of induction coils. ### Claim 8 (depends on 1) The induction cooking apparatus according to claim 1, wherein the at least one foil extends uninterrupted beneath the plurality of induction coils. ### Claim 9 (depends on 1) The induction cooking apparatus according to claim 1, further comprising: a beam structure supporting the at least one foil and the array of induction coils, wherein the at least one foil is disposed between the array of induction coils and the beam structure, and wherein the beam structure defines at least one beam aperture aligned with the at least one foil aperture and configured to receive the at least one conductor. ### Claim 10 (depends on 1) The induction cooking apparatus according to claim 1, wherein the at least one conductor includes a first conductor and a second conductor, the first conductor extending through a first foil aperture of the at least one foil aperture and connecting to a first end of the induction coil, and the second conductor extending through a second foil aperture of at least one foil aperture and connecting to a second end of the induction coil. ### Claim 11 (depends on 9) The induction cooking apparatus according to claim 9, wherein the beam structure is configured to extend across a housing of the cooking apparatus from a first side to a second side, opposite the first side. ### Claim 12 (depends on 1) The induction cooking apparatus according to claim 1, wherein the at least one foil has a thickness of less than 4 mm. ### Claim 13 (depends on 12) The induction cooking apparatus according to claim 12, wherein the at least one foil comprises multiple magnetic foils in a stacked configuration. ### Claim 14 An induction cooking apparatus comprising: a housing forming an enclosure comprising a first side and a second side, opposite the first side; a plurality of coil beam assemblies each comprising: an array of induction coils, the induction coils comprising conductive windings disposed around a coil former; at least one magnetic foil extending beneath the plurality of induction coils; a beam structure comprising a first end portion and a second end portion extending across the housing of the cooking apparatus from the first side to the second side, wherein the beam structure is configured to support the array of induction coils; and an electrical circuit in communication with each of the plurality of induction coils, wherein the magnetic foil extends under at least a portion of each of the induction coils in the array; and wherein the coil beam assemblies extend from the first side to the second side forming an induction coil matrix. ### Claim 15 (depends on 14) The induction cooking apparatus according to claim 14, wherein the coil former includes a spindle structure comprising a base extending approximately to a perimeter of the induction coil between the magnetic foil and the conductive windings. ### Claim 16 (depends on 14) The induction cooking apparatus according to claim 14, wherein the array is configured to extend linearly across the cooking apparatus from the first side to a second side, opposite the first side. ### Claim 17 (depends on 16) The induction cooking apparatus according to claim 16, wherein the beam is configured to connect to a housing of the cooking apparatus on the first side and the second side supporting the array. ### Claim 18 (depends on 14) The induction cooking apparatus according to claim 14, wherein the at least one magnetic foil extending beneath the plurality of induction coils comprises a first magnetic foil and a second magnetic foil in a stacked configuration. ### Claim 19 (depends on 18) The induction cooking apparatus according to claim 18, wherein the stacked configuration of the first magnetic foil and the second magnetic foil form a thickness of less than 4 mm between the beam structure and the plurality of induction coils. ### Claim 20 An induction coil assembly fora cooking apparatus comprising: a plurality of induction coils arranged in a linear array, each induction coil comprising conductive windings disposed around a coil former, wherein a length of the linear array corresponds to the number of induction coils arranged in the linear array; at least one magnetically permeable foil extending beneath the linear array formed by the induction coils, wherein the magnetically permeable foil forms a mat having a substantially uniform thickness, wherein the magnetically permeable foil extends beneath each of the induction coils forming the linear array; a beam structure configured to extend across a housing of the cooking apparatus from a first side to a second side, opposite the first side, wherein the beam structure is configured to support the magnetically permeable foils and the array of induction coils; and an electrical circuit in connection with the beam structure and in communication with each of the plurality of induction coils forming the linear array, wherein the at least one magnetically permeable foil extends the length of the linear array, and wherein a width of the at least one magnetically permeable foil corresponds to a single induction coil forming the linear array.