# US 12,191,902 B2 · Mobile electronic device cases for electromagnetic shielding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,191,902 B2 - Document ID: US12191902B2 - Status: Granted - Kind: B2 - Application number: 18/768,599 - Filed: 2024-07-10 - Published: 2024-10-31 - Granted: 2025-01-07 - Earliest claimed: 2017-05-25 - Assignees: Spigen Korea Co., Ltd. - Applicants: Spigen Korea Co., Ltd. - Inventors: Seungjun Lee; Seungjoo Kim; Sunwoo Yun; Jaehong Cho; Dae-Young Kim - Web page: https://patentgrep.com/patent/US12191902B2 ## CPC - H04B 1/3888: Arrangements for carrying or protecting transceivers - A45C 11/00: Receptacles for purposes not provided for in groups A45C1/00-A45C9/00 (specially adapted for toiletry or cosmetic equipment A45D29/20, A45D44/18; travelling sewing kits A45F3/48) - A45C 11/182: {Credit card holders} - A45C 13/1069: {magnetic} - H01F 27/366: {made of ferromagnetic material} - H01F 38/14: Inductive couplings - H02J 7/70: characterised by the mechanical construction - H02J 50/10: using inductive coupling - A45C 11/002: {for storing portable handheld communication devices, e.g. pagers or smart phones} - A45C 11/003: {for storing portable computing devices, e.g. laptops, tablets or calculators} - H02J 50/005: {Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices} - H04B 1/3877: Arrangements for enabling portable transceivers to be used in a fixed position, e.g. cradles or boosters - H04B: TRANSMISSION - A45C: PURSES; LUGGAGE; HAND CARRIED BAGS - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract Devices and products for shielding a mobile electronic device enclosed in a case from an effect of electromagnetic flux generated when a magnetic auxiliary device for the mobile electronic device having a magnet is attached to the case are described. According to one embodiment, the case comprises a protective cover configured to at least partially cover the mobile electronic device and a ferromagnetic plate made of SPCC disposed on the protective cover. In one example embodiment, the at least one ferromagnetic plate is to magnetically couple with the magnet of the magnetic auxiliary device attached to a contact surface of the case, and the at least one ferromagnetic plate is to shield the mobile electronic device from the magnetic flux generated. ## Claims ### Claim 1 A case for a mobile electronic device having a coil for wireless charging, wherein the coil is disposed in the mobile electronic device and has an inner boundary and an outer boundary, the case comprising: a protective cover configured to at least partially cover the mobile electronic device; and at least one ferromagnetic plate disposed on the protective cover, wherein the at least one ferromagnetic plate is positioned not to block magnetic waves passing through an area formed by the inner boundary of the coil, wherein the at least one ferromagnetic plate is positioned not to overlap with an orthographic parallel projection of the area formed by the inner boundary of the coil when the mobile electronic device is at least partially covered by the protective cover, wherein the at least one ferromagnetic plate is to magnetically couple with a magnet of a magnetic auxiliary device attached to a contact surface of the case; and wherein the at least one ferromagnetic plate is to shield the mobile electronic device from magnetic flux generated when the magnetic auxiliary device is attached to the contact surface of the case. ### Claim 2 (depends on 1) The case of claim 1, wherein the at least one ferromagnetic plate comprises a steel plate cold commercial (SPCC). ### Claim 3 (depends on 1) The case of claim 1, further comprising a second magnet in a shape of the at least one ferromagnetic plate to couple with the at least one ferromagnetic plate. ### Claim 4 (depends on 1) The case of claim 1, wherein a gap between the mobile electronic device and an inner surface of the protective cover is at least 0.3 milli-meter. ### Claim 5 (depends on 2) The case of claim 2, wherein a thickness of the SPCC is at least 0.6 milli-meter. ### Claim 6 (depends on 2) The case of claim 2, wherein a size of the SPCC is equal or greater than a size of the magnet of the magnetic auxiliary device. ### Claim 7 (depends on 2) The case of claim 2, wherein the SPCC is treated with a rust inhibitor. ### Claim 8 (depends on 1) The case of claim 1, wherein the at least one ferromagnetic plate is attached to the protective cover by an adhesive or a tape. ### Claim 9 (depends on 1) The case of claim 1, wherein the at least one ferromagnetic plate is attached to an inner surface of the protective cover. ### Claim 10 (depends on 9) The case of claim 9, wherein the inner surface of the protective cover has a recess in which the at least one ferromagnetic plate is received. ### Claim 11 (depends on 1) The case of claim 1, further comprising a protective frame sheet attached to the at least one ferromagnetic plate. ### Claim 12 (depends on 1) The case of claim 1, wherein the at least one ferromagnetic plate is arranged to form a rounded shape having an inner boundary. ### Claim 13 (depends on 12) The case of claim 12, wherein the inner boundary of the rounded shape symmetrically aligns to orthographic parallel projections of the inner boundary and the outer boundary of the coil. ### Claim 14 (depends on 13) The case of claim 13, wherein the inner boundary of the rounded shape is circular. ### Claim 15 A case for a mobile electronic device having a coil for wireless charging, wherein the coil is disposed in the mobile electronic device and has an inner boundary and an outer boundary, the case comprising: a protective cover configured to at least partially cover the mobile electronic device; and a ferromagnetic plate made of steel plate cold commercial (SPCC) disposed on the protective cover, wherein the ferromagnetic plate is positioned not to block magnetic waves passing through an area formed by the inner boundary of the coil, and wherein the ferromagnetic plate is positioned not to overlap with an orthographic parallel projection of the area formed by the inner boundary of the coil when the mobile electronic device is at least partially covered by the protective cover. ### Claim 16 (depends on 15) The case of claim 15, wherein the ferromagnetic plate is to magnetically couple with a magnet of a magnetic auxiliary device attached to a surface of the protective cover. ### Claim 17 (depends on 16) The case of claim 16, wherein the ferromagnetic plate is to block magnetic flux generated by the magnet of the magnetic auxiliary device from passing through the ferromagnetic plate. ### Claim 18 (depends on 15) The case of claim 15, wherein a thickness of the SPCC is at least 0.6 milli-meter. ### Claim 19 (depends on 16) The case of claim 16, wherein a size of the SPCC is equal or greater than a size of the magnet of the magnetic auxiliary device. ### Claim 20 (depends on 15) The case of claim 15, wherein a gap between the mobile electronic device and an inner surface of the protective cover is at least 0.3 milli-meter.