# US 8,464,544 B2 · Refrigerator and control method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,464,544 B2 - Document ID: US8464544B2 - Status: Granted - Kind: B2 - Application number: 12/382,865 - Filed: 2009-03-25 - Published: 2009-10-08 - Granted: 2013-06-18 - Earliest claimed: 2008-04-07 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Young Shik Shin; Jeong Han Kim - Inventors: Young Shik Shin; Jeong Han Kim - Web page: https://patentgrep.com/patent/US8464544B2 ## CPC - F25D 29/00: Arrangement or mounting of control or safety devices - F25D 11/02: with cooling compartments at different temperatures - F25D 2331/805: Cans - F25D 2500/04: Calculation of parameters - F25D 2600/06: Controlling according to a predetermined profile - F25D 2700/08: Sensors using Radio Frequency Identification [RFID] - F25D 2700/16: Sensors measuring the temperature of products - F25D: REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR (refrigerated showcases A47F3/04; thermally-insulated vessels for domestic use A47J41/00; refrigerated vehicles, see the appropriate subclasses of classes B60 - B64; containers with thermal insulation in general B65D81/38; heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants, or materials for the production of heat or cold by chemical reactions other than by combustion C09K5/00; thermally-insulated vessels for liquefied or solidified gases F17C; air-conditioning or air-humidification F24F; refrigeration machines, plants, or systems F25B; cooling of instruments or comparable apparatus without refrigeration G12B) ## Abstract A refrigerator capable of supercooling a target object and a control method thereof are provided. The refrigerator includes a temperature sensor which senses a temperature of the target object in the cooling compartment, wherein the temperature sensor is prevented from being in contact with ambient cool air and is installed on a bottom surface on which the target object is placed so as to sense only the temperature of the target object. Further, the control method includes sensing a temperature of the target object at each interval of a specified time Δt, calculating a difference between two temperatures sensed at specified time intervals, and comparing the difference between two temperatures with a predetermined reference value ΔTc to determine the supercooled state of the target object. ## Claims ### Claim 1 A control method of a refrigerator to determine a supercooled state of a target object in a cooling compartment, the method comprising: sensing a temperature of the target object at each interval of a specified time Δt; calculating a difference between two of the sensed temperatures; comparing the difference between the two sensed temperatures with a predetermined reference value ΔTc to determine the supercooled state of the target object; and determining that supercooling is normally in progress if the difference between the two temperatures is smaller than the predetermined reference value. ### Claim 2 (depends on 1) The method according to claim 1, further comprising determining whether supercooling of the target object is achieved comprising determining whether the temperature of the target object is equal to or lower than a target supercooling temperature if it is determined that supercooling is normally in progress. ### Claim 3 (depends on 1) The method according to claim 1, further comprising determining that supercooling fails to be achieved if the difference between the two temperatures is equal to or larger than the predetermined reference value. ### Claim 4 (depends on 3) The method according to claim 3, further comprising stopping cooling of the target object if it is determined that supercooling fails to be achieved. ### Claim 5 (depends on 1) The method according to claim 1, wherein the reference value is larger than a temperature variation in the cooling compartment generated according to whether cool air is supplied to the cooling compartment or an opening/closing operation of the cooling compartment and is smaller than a temperature variation due to a rapid temperature increase when supercooling fails to be achieved. ### Claim 6 (depends on 1) The method according to claim 1, further comprising varying the reference value according to a beverage type of the target object. ### Claim 7 (depends on 6) The method according to claim 6, further comprising manually inputting a type of the target object by a user, or automatically inputting and identifying the type by a barcode or RFID. ### Claim 8 (depends on 1) The method according to claim 1, further comprising designating the specified time using the predetermined reference value and a temperature inclination due to a temperature increase when the supercooling fails to be achieved. ### Claim 9 (depends on 1) The method according to claim 1, further comprising displaying determination results of the supercooled state. ### Claim 10 (depends on 1) The method according to claim 1, wherein the calculating a difference between two sensed temperatures is performed when the sensed temperatures are lower than a freezing point of the target object. ### Claim 11 A refrigerator which determines a supercooled state of a target object, comprising: a cooling compartment, the target object being in the cooling compartment; a temperature sensor which senses a temperature of the target object in the cooling compartment; and a controller which calculates a difference between two temperatures of the sensed temperatures at specified time intervals and compares the difference between the two temperatures with a predetermined reference value ΔTc to determine the supercooled state of the target object; wherein the controller determines that supercooling is normally in progress if the difference between the two temperatures is smaller than the predetermined reference value. ### Claim 12 (depends on 11) The refrigerator according to claim 11, further comprising: a memory which stores reference values according to a type of the target object, wherein the controller varies the predetermined reference value ΔTc according to a type of the target object. ### Claim 13 (depends on 12) The refrigerator according to claim 12, further comprising an input unit, wherein the type of the object is input to the input unit by a user. ### Claim 14 (depends on 12) The refrigerator according to claim 12, further comprising a reader to automatically read a type of the target object. ### Claim 15 (depends on 11) The refrigerator according to claim 11, further comprising a display unit which displays determination results of the supercooled state.