# US 10,310,440 B2 · Image forming apparatus and power supply method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,310,440 B2 - Document ID: US10310440B2 - Status: Granted - Kind: B2 - Application number: 16/019,836 - Filed: 2018-06-27 - Published: 2018-11-08 - Granted: 2019-06-04 - Earliest claimed: 2016-12-29 - Assignees: Kabushiki Kaisha Toshiba; Toshiba Tec Kabushiki Kaisha - Applicants: Kabushiki Kaisha Toshiba; Toshiba Tec Kabushiki Kaisha - Inventors: Tetsuo Kato - Web page: https://patentgrep.com/patent/US10310440B2 ## CPC - G03G 15/80: {Details relating to power supplies, circuits boards, electrical connections} - B41J 23/00: Power drives for actions or mechanisms (B41J9/00 {, B41J19/305} take precedence) - B41J 29/38: Drives, motors, controls or automatic cut-off devices for the entire printing mechanism - G03G 15/5004: {Power supply control, e.g. power-saving mode, automatic power turn-off} - G06F 1/26: Power supply means, e.g. regulation thereof (for memories G11C) - G06F 1/30: Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations (for resetting only G06F1/24) - G06F 1/3212: Monitoring battery levels, e.g. power saving mode being initiated when battery voltage goes below a certain level - G06F 1/3287: by switching off individual functional units in the computer system - G06F 3/1221: {with regard to power consumption} - G06F 3/1229: {Printer resources management or printer maintenance, e.g. device status, power levels} - H04N 1/00885: {Power supply means, e.g. arrangements for the control of power supply to the apparatus or components thereof} - Y02D 10/00: Energy efficient computing, e.g. low power processors, power management or thermal management - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract An image forming apparatus having a plurality of functional units includes a power failure detection circuit configured to detect a power failure of an external power supply for the image forming apparatus, a rechargeable battery unit, and a control unit. The control unit switches the power supply source of the image forming apparatus from the external power supply to the rechargeable battery unit, and selects one or more of the functional units to power through the rechargeable battery unit based on a remaining capacity of the rechargeable battery unit, when the power failure of the external power supply is detected. ## Claims ### Claim 1 An image forming apparatus having a plurality of functional units, comprising: a plurality of rechargeable batteries, each one of the plurality of rechargeable batteries having a different capacity from the other; and a control unit configured to detect a remaining capacity of each of the plurality of rechargeable batteries; select a rechargeable battery with the largest capacity of the plurality of rechargeable batteries to power each of the plurality of functional units; and when the remaining capacity of the rechargeable battery with the largest capacity is discharged below a threshold value, switch to a rechargeable battery of the plurality of rechargeable batteries with a capacity that is smaller than the rechargeable battery with the largest capacity, and supply power to at least one of the functional units with the rechargeable battery with the smaller capacity. ### Claim 2 (depends on 1) The apparatus according to claim 1, wherein when the control unit switches to the rechargeable battery with the smaller capacity, the control unit supplies power to each of the functional units, other than an image forming functional unit, with the rechargeable battery with the smaller capacity. ### Claim 3 (depends on 1) The apparatus according to claim 1, wherein when the control unit switches to the rechargeable battery with the smaller capacity, the control unit issues a command to display a message that the image forming functional unit will be powered down. ### Claim 4 (depends on 1) The apparatus according to claim 1, wherein if the rechargeable battery with the smaller capacity is the rechargeable battery with the smallest capacity of the plurality of rechargeable batteries, the control unit supplies power to a communication functional unit of the plurality of functional units with the rechargeable battery with the smallest capacity. ### Claim 5 (depends on 4) The apparatus according to claim 4, wherein the control unit displays a message that only the communication functional unit of the plurality of functional units is useable. ### Claim 6 (depends on 1) The apparatus according to claim 1, wherein when a remaining capacity of a smallest capacity of the plurality of batteries is discharged below a threshold value, the control unit issues an instruction to display a message that all of the plurality of functional units will be powered down. ### Claim 7 A power supply method performed by an image forming apparatus including a plurality of rechargeable batteries, each one of the plurality of the rechargeable batteries having a different capacity from the other, the method comprising: detecting a remaining capacity of each of the plurality of rechargeable batteries; selecting a rechargeable battery with a largest capacity of the plurality of rechargeable batteries to power each of the plurality of functional units; and when the remaining capacity of the rechargeable battery with the largest capacity is discharged below a threshold value, switching to a rechargeable battery of the plurality of rechargeable batteries with a capacity that is smaller than the rechargeable battery with the largest capacity, supplying power to at least one of the functional units with the rechargeable battery with the smaller capacity. ### Claim 8 (depends on 7) The method according to claim 7, wherein upon switching to the rechargeable battery with the smaller capacity, supplying power to each of the functional units, other than an image forming functional unit, with the rechargeable battery with the smaller capacity. ### Claim 9 (depends on 7) The method according to claim 7 further comprising: upon switching to the rechargeable battery with the smaller capacity, displaying a message that the image forming functional unit will be powered down. ### Claim 10 (depends on 7) The method according to claim 7, wherein if the rechargeable battery with the smaller capacity is the rechargeable battery with the smallest capacity of the plurality of rechargeable batteries, supplying power to a communication functional unit of the plurality of functional units with the rechargeable battery with the smallest capacity. ### Claim 11 (depends on 10) The method according to claim 10, further comprising: displaying a message that only the communication functional unit of the plurality of functional units is useable. ### Claim 12 (depends on 7) The method according to claim 7, further comprising: upon detecting a remaining capacity of a smallest capacity of the plurality of batteries is discharged below a threshold value, displaying a message that all of the plurality of functional units will be powered down.