# US 10,246,809 B2 · Washing machine and method of controlling the same using an AC motor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,246,809 B2 - Document ID: US10246809B2 - Status: Granted - Kind: B2 - Application number: 15/011,236 - Filed: 2016-01-29 - Published: 2016-09-01 - Granted: 2019-04-02 - Earliest claimed: 2015-01-30 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd - Inventors: Hyun Oh Kim; Jun Hyun Park; Sung Mo Lee - Web page: https://patentgrep.com/patent/US10246809B2 ## CPC - D06F 33/40: of centrifugal separation of water from the laundry - D06F 37/304: {Arrangements or adaptations of electric motors} - D06F 37/40: for driving the receptacle and an agitator or impeller, e.g. alternatively {(D06F37/304, D06F37/308 take precedence)} - D06F 34/20: Parameters relating to constructional components, e.g. door sensors - D06F 34/28: Arrangements for programme selection, e.g. control panels therefor; Arrangements for indicating programme parameters, e.g. the selected programme or its progress - D06F 2103/24: Spin speed; Drum movements - D06F 2105/46: Drum speed; Actuation of motors, e.g. starting or interrupting - D06F 2105/58: Indications or alarms to the control system or to the user - D06F: LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES ## Abstract A washing machine includes an alternating current (AC) motor which generates torque, a clutch assembly which selectively transfers the torque to a rotating tub and a pulsator, a speed detector which detects a rotary speed of the clutch assembly, and a controller configured to repetitively perform operating and stopping the operating of the AC motor based on a predetermined target speed and the rotary speed of the clutch assembly in a spin-drying operation. The controller gradually increases the torque of the AC motor while operating the AC motor. ## Claims ### Claim 1 A washing machine comprising: an alternating current (AC) motor configured to generate torque; a clutch assembly configured to selectively transfer the torque to a rotating tub and a pulsator; a speed detector configured to detect a rotary speed of the clutch assembly; and a controller configured to repetitively perform operating and stopping the operation of the AC motor based on a predetermined target speed and the rotary speed of the clutch assembly during a spin-drying operation, wherein the controller is configured to gradually increase the torque of the AC motor while operating the AC motor during the spin-drying operation. ### Claim 2 (depends on 1) The washing machine of claim 1, wherein the controller is configured to control a phase angle of AC power supplied from an external power supply and to supply the AC power controlled in phase angle to the AC motor while operating the AC motor. ### Claim 3 (depends on 2) The washing machine of claim 2, wherein the controller is configured to supply at least a part of one cycle of an AC current supplied from the external power supply to the AC motor while operating the AC motor. ### Claim 4 (depends on 3) The washing machine of claim 3, further comprising a driving switch unit configured to conduct or cut off the power supplied from the external power supply to the AC motor. ### Claim 5 (depends on 4) The washing machine of claim 4, wherein the controller is configured to turn on the driving switch unit for a conduction time in one cycle of the AC power supplied from the external power supply while operating the AC motor. ### Claim 6 (depends on 5) The washing machine of claim 5, wherein the controller is configured to gradually increase the conduction time while operating the AC motor. ### Claim 7 (depends on 1) The washing machine of claim 1, wherein the controller is configured to stop the operating of the AC motor when the rotary speed is greater than a sum of the target speed and an allowable error while operating the AC motor. ### Claim 8 (depends on 1) The washing machine of claim 1, wherein the controller is configured to begin the operating of the AC motor when the rotary speed is smaller than a difference between the target speed and an allowable error while stopping the operating of the AC motor. ### Claim 9 (depends on 1) The washing machine of claim 1, wherein the target speed varies according to a time in which the spin-drying operation is performed. ### Claim 10 (depends on 1) The washing machine of claim 1, wherein the speed detector comprises: a position indicating member configured to rotate together with the clutch assembly; and a speed sensor configured to detect the position indicating member and output an electric signal corresponding to whether the position indicating member is detected. ### Claim 11 (depends on 10) The washing machine of claim 10, wherein the controller is configured to warn a user of a failure of the speed sensor when the rotary speed is “0” after the AC motor is operated. ### Claim 12 (depends on 10) The washing machine of claim 10, wherein the controller is configured to warn a user of omission of the position indicating member when the rotary speed is smaller than a predetermined reference speed after the AC motor is fully operated. ### Claim 13 A method of controlling a washing machine, comprising: operating an AC motor that generates torque during a spin-drying operation; detecting a rotary speed of a clutch assembly that transfers the torque to a rotating tub and a pulsator; and repetitively performing operating and stopping the operating of the AC motor based on a predetermined target speed and the rotary speed of the clutch assembly during the spin-drying operation, wherein the operating of the AC motor comprises gradually increasing the torque of the AC motor during the spin-drying operation. ### Claim 14 (depends on 13) The method of claim 13, wherein the gradually increasing of the torque of the AC motor comprises: controlling a phase angle of AC power supplied from an external power supply; and supplying the AC power controlled in phase angle to the AC motor. ### Claim 15 (depends on 14) The method of claim 14, wherein the supplying of the AC power controlled in phase angle to the AC motor comprises supplying at least a part of one cycle of an AC current supplied from the external power supply to the AC motor. ### Claim 16 (depends on 13) The method of claim 13, wherein the repetitively performing the operating and stopping of the operating of the AC motor comprises stopping the operating of the AC motor when the rotary speed is greater than a sum of the target speed and an allowable error while operating the AC motor. ### Claim 17 (depends on 13) The method of claim 13, wherein the repetitively performing the operating and stopping of the operating of the AC motor comprises beginning the operating of the AC motor when the rotary speed is smaller than a difference between the target speed and an allowable error while stopping the operating of the AC motor. ### Claim 18 (depends on 13) The method of claim 13, wherein the target speed varies according to a time in which the spin-drying operation is performed. ### Claim 19 (depends on 13) The method of claim 13, further comprising warning a user of a failure of a speed sensor which detects the rotary speed of the clutch assembly when the rotary speed is “0” after the AC motor is operated. ### Claim 20 (depends on 13) The method of claim 13, further comprising warning a user of a failure of a speed sensor which detects the rotary speed of the clutch assembly when the rotary speed is smaller than a predetermined reference speed after the AC motor is fully operated.