# US 12,760,698 B2 · Exhaust gas recirculation device and exhaust gas recirculation method for internal combustion engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,760,698 B2 - Document ID: US12760698B2 - Status: Granted - Kind: B2 - Application number: 18/982,454 - Filed: 2024-12-16 - Published: 2025-06-26 - Granted: 2026-10-13 - Earliest claimed: 2023-12-20 - Assignees: Toyota Jidosha Kabushiki Kaisha - Applicants: Toyota Jidosha Kabushiki Kaisha - Inventors: Tomoya Oshima - Web page: https://patentgrep.com/patent/US12760698B2 ## CPC - F02M 26/47: the characteristics being temperatures, pressures or flow rates - F02M 26/22: with coolers in the recirculation passage - F02M 2026/004: {EGR valve controlled by a temperature signal or an air/fuel ratio (lambda) signal} - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF ## Abstract An exhaust gas recirculation device and an exhaust gas recirculation method for an internal combustion engine are provided. An EGR cooler performs heat exchange between coolant of the internal combustion engine and EGR gas. An EGR valve is provided in a section of an EGR passage that is between an intake passage and the EGR cooler. The EGR valve includes a temperature sensitive portion, with which the EGR gas comes into contact. An EGR gas temperature is a temperature of the EGR gas in contact with the temperature sensitive portion. A valve body opens the EGR valve when the EGR gas temperature is higher than a prescribed temperature, thereby allowing the EGR gas to flow. ## Claims ### Claim 1 An exhaust gas recirculation device for an internal combustion engine, the exhaust gas recirculation device comprising: an EGR passage that delivers some of exhaust gas of the internal combustion engine to an intake passage of the internal combustion engine as an EGR gas; an EGR cooler provided in the EGR passage, the EGR cooler performing heat exchange between coolant of the internal combustion engine and the EGR gas; and an EGR valve provided in a section of the EGR passage that is between the intake passage and the EGR cooler, wherein the EGR valve includes: a temperature sensitive portion with which the EGR gas comes into contact, an EGR gas temperature being a temperature of the EGR gas that comes into contact with the temperature sensitive portion; a displaceable valve body that opens the EGR valve when the EGR gas temperature is higher than a prescribed temperature, thereby allowing the EGR gas to flow, wherein the displaceable valve body includes a through-hole in which some of the EGR gas can pass while the displaceable valve body is closed. ### Claim 2 (depends on 1) The exhaust gas recirculation device for an internal combustion engine according to claim 1, wherein the temperature sensitive portion is disposed in a section downstream of the displaceable valve body in a flow direction of the EGR gas. ### Claim 3 An exhaust gas recirculation device for an internal combustion engine, the exhaust gas recirculation device comprising: an EGR passage that delivers some of exhaust gas of the internal combustion engine to an intake passage of the internal combustion engine as an EGR gas; an EGR cooler provided in the EGR passage, the EGR cooler performing heat exchange between coolant of the internal combustion engine and the EGR gas; and an EGR valve provided in a section of the EGR passage that is between the intake passage and the EGR cooler, wherein the EGR valve includes: a temperature sensitive portion with which the EGR gas comes into contact, an EGR gas temperature being a temperature of the EGR gas that comes into contact with the temperature sensitive portion, and a displaceable valve body that opens the EGR valve when the EGR gas temperature is higher than a prescribed temperature, thereby allowing the EGR gas to flow, wherein the temperature sensitive portion is disposed in a section downstream of the displaceable valve body in a flow direction of the EGR gas, the EGR valve includes a bypass passage, the EGR gas bypasses the displaceable valve body by flowing through the bypass passage, and the bypass passage is formed so that the EGR gas flowing out of the bypass passage is directed toward the temperature sensitive portion. ### Claim 4 (depends on 1) The exhaust gas recirculation device for an internal combustion engine according to claim 1, wherein the fuel of the internal combustion engine is hydrogen gas. ### Claim 5 (depends on 1) The exhaust gas recirculation device for an internal combustion engine according to claim 1, wherein, when the EGR valve is open, an air-fuel mixture burned in the internal combustion engine has an air excess ratio of 1 or less. ### Claim 6 An exhaust gas recirculation method for an internal combustion engine, the exhaust gas recirculation method being executed by processing circuitry, the method comprising: introducing some of exhaust gas of the internal combustion engine into an intake passage of the internal combustion engine as an EGR gas by causing the exhaust gas to pass through the EGR passage; and using an EGR cooler provided in the EGR passage, thereby performing heat exchange between coolant of the internal combustion engine and the EGR gas, an EGR valve is provided in a section of the EGR passage that is between the intake passage and the EGR cooler, wherein the EGR valve includes a displaceable valve body and a temperature sensitive portion with which the EGR gas comes into contact, an EGR gas temperature is a temperature of the EGR gas in contact with the temperature sensitive portion of the EGR valve, wherein the temperature sensitive portion is disposed in a section downstream of the displaceable valve body in a flow direction of the EGR gas, and wax is sealed inside the temperature sensitive portion, and the displaceable valve body opens the EGR valve when the EGR gas temperature is higher than a prescribed temperature, and wherein the displaceable valve body includes a through-hole in which some of the EGR gas can pass while the displaceable valve body is closed. ### Claim 7 (depends on 6) The exhaust gas recirculation device for an internal combustion engine according to claim 6, wherein the EGR valve is actuated by the temperature sensitive portion such that the temperature sensitive portion drives the displaceable valve body to open and close the EGR valve. ### Claim 8 (depends on 6) The exhaust gas recirculation method for an internal combustion engine according to claim 6, wherein the prescribed temperature is a lowest temperature of the EGR gas at which generation of condensed water is suppressed.