# US 2021/0340892 A1 · Apparatus and method for detecting engine oil replacement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0340892 A1 - Document ID: US20210340892A1 - Status: Published application - Kind: A1 - Application number: 17/070,455 - Filed: 2020-10-14 - Published: 2021-11-04 - Earliest claimed: 2020-04-29 - Assignees: Hyundai Motor Company; Kia Motors Corporation - Applicants: Hyundai Motor Company; Kia Motors Corporation - Inventors: Hyuk Im; Joowon Lee; Kiwon Park; Jinnam Kim - Web page: https://patentgrep.com/patent/US20210340892A1 ## CPC - F01M 11/10: Indicating devices; Other safety devices - F01M 2011/1473: {by considering temperature} - F01M 2250/00: Measuring - F01M: LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING ## Abstract A method for detecting engine oil replacement may include determining a measured oil temperature change amount based on an engine oil temperature measurement value during an engine turned-off period determined based on turning-off/on signals, determining a modeled oil temperature change amount based on a temperature change model estimating the engine oil temperature without an engine oil replacement event according to the engine turned-off period, temperature information related to the engine at an engine turned-off time point, and temperature information related to the engine at a turned-on time point, comparing a difference value between the measured oil temperature change amount and the modeled oil temperature change amount with a reference temperature, determining whether the engine oil replacement event has occurred during the engine turned-off period based on a comparison result, and resetting an engine oil replacement timing and displaying the reset engine oil replacement timing in a user interface. ## Claims ### Claim 1 A method of detecting engine oil replacement, the method comprising: determining, by a controller, a measured oil temperature change amount according to an engine oil temperature measurement value during an engine turned-off period determined according to turning-off/on signals of an engine; determining, by the controller, a modeled oil temperature change amount according to a temperature change model that estimates an engine oil temperature without an engine oil replacement event according to the engine turned-off period, temperature information related to the engine at an engine turned-off time point, and temperature information related to the engine at a turned-on time point of the engine; comparing, by the controller, a difference value between the measured oil temperature change amount and the modeled oil temperature change amount with a reference temperature; determining, by the controller, whether the engine oil replacement event has occurred during the engine turned-off period according to a result of the comparing; and resetting, by the controller, an engine oil replacement timing and displaying the reset engine oil replacement timing in a user interface. ### Claim 2 (depends on 1) The method of claim 1, wherein the determining of whether the engine oil replacement event has occurred includes: determining that the engine oil replacement event has occurred upon concluding that the difference value between the measured oil temperature change amount and the modeled oil temperature change amount is greater than the reference temperature. ### Claim 3 (depends on 2) The method of claim 2, wherein the measured oil temperature change amount is a maximum temperature change amount determined according to the engine oil temperature measurement value, and wherein the modeled oil temperature change amount is a maximum temperature change amount determined according to the engine oil temperature estimated by the temperature change model. ### Claim 4 (depends on 1) The method of claim 1, further including: prior to the determining the measured oil temperature change amount according to the engine oil temperature measurement value and prior to the determining the modeled oil temperature change amount according to the temperature change model, determining whether a diagnosis condition for determining whether the engine oil replacement has occurred is satisfied. ### Claim 5 (depends on 4) The method of claim 4, wherein the diagnosis condition includes at least one of a condition that the engine turned-off period is within a predetermined reference period, a condition that a sensor connected to the controller and configured for detecting the engine oil temperature is in a normal state, and a condition that the engine oil temperature at the engine turned-off time point is above a predetermined reference temperature. ### Claim 6 (depends on 2) The method of claim 2, wherein the determining that the engine oil replacement event has occurred includes storing engine oil replacement information in a memory. ### Claim 7 (depends on 1) The method of claim 1, wherein the temperature information related to the engine includes at least one of an ambient temperature, a coolant temperature, and the engine oil temperature. ### Claim 8 (depends on 1) The method of claim 1, wherein the controller includes: a processor; and a non-transitory storage medium on which a program for performing the method of claim 1 is recorded and executed by the processor. ### Claim 9 (depends on 1) A non-transitory computer readable medium on which a program for performing the method of claim 1 is recorded. ### Claim 10 An apparatus of detecting engine oil replacement, the apparatus comprising: a controller configured for determining an engine turned-off period and determining whether an engine oil replacement event has occurred during the engine turned-off period; and a temperature change model that estimates an engine oil temperature without the engine oil replacement event according to the engine turned-off period, temperature information related to an engine at an engine turned-off time point, and temperature information related to the engine at a turned-on time point of the engine, wherein the controller is configured to determine whether the engine oil replacement event has occurred by comparing a reference temperature with a difference value between a measured oil temperature change amount determined according to an engine oil temperature measurement value and a modeled oil temperature change amount determined according to the temperature change model. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the controller is configured to: periodically receive the engine oil temperature from a temperature sensor that is connected to the controller and configured to measure the engine oil temperature; determine a plurality of temperature change amounts for unit time during the engine turned-off period; and determine the measured oil temperature change amount as a maximum temperature change amount among the plurality of temperature change amounts. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the controller is configured to: estimate an engine oil temperature change during the engine turned-off period using the temperature change model; determine a plurality of temperature change amounts for unit time according to the estimated engine oil temperature; and determine the modeled oil temperature change amount as a maximum temperature change amount among the plurality of temperature change amounts for unit time determined according to the estimated engine oil temperature. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the temperature information related to the engine includes at least one of an ambient temperature, a coolant temperature, and the engine oil temperature. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein the controller is configured to determine that the engine oil replacement event has occurred upon concluding that the difference value between the measured oil temperature change amount and the modeled oil temperature change amount is greater than the reference temperature. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the measured oil temperature change amount is a maximum temperature change amount determined according to the engine oil temperature measurement value, and wherein the modeled oil temperature change amount is a maximum temperature change amount determined according to the engine oil temperature estimated by the temperature change model. ### Claim 16 (depends on 14) The apparatus of claim 14, wherein the controller is configured to store engine oil replacement information in a memory, to reset engine oil replacement timing, and to display the reset engine oil replacement timing to a user interface. ### Claim 17 (depends on 10) The apparatus of claim 10, wherein the controller is configured to determine whether the engine oil replacement event has occurred upon concluding that a diagnosis condition for determining whether the engine oil replacement has occurred is satisfied; and wherein the diagnosis condition includes at least one of a condition that the engine turned-off period is within a predetermined reference period, a condition that a sensor connected to the controller and configured for detecting the engine oil temperature is in a normal state, and a condition that the engine oil temperature at the engine turned-off time point is above a predetermined reference temperature.