# US 7,607,301 B2 · Exhaust gas heat exchanger, exhaust gas recirculation system, and exhaust gas heat exchanging method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,607,301 B2 - Document ID: US7607301B2 - Status: Granted - Kind: B2 - Application number: 11/501,530 - Filed: 2006-08-09 - Published: 2007-03-01 - Granted: 2009-10-27 - Earliest claimed: 2005-08-30 - Assignees: Denso Corporation - Inventors: Masaki Harada; Haruhiko Watanabe - Web page: https://patentgrep.com/patent/US7607301B2 ## CPC - F02M 31/093: Air intake passage surrounding the exhaust gas passage; Exhaust gas passage surrounding the air intake passage - F02B 29/0406: {Layout of the intake air cooling or coolant circuit} - F02M 26/09: Constructional details, e.g. structural combinations of EGR systems and supercharger systems; Arrangement of the EGR and supercharger systems with respect to the engine - F02M 26/17: in relation to the intake system - F02M 26/30: Connections of coolers to other devices, e.g. to valves, heaters, compressors or filters; Coolers characterised by their location on the engine - F02M 26/31: Air-cooled heat exchangers - F02M 26/35: with means for cleaning or treating the recirculated gases, e.g. catalysts, condensate traps, particle filters or heaters - F02M 26/06: Low pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust downstream of the turbocharger turbine and reintroduced into the intake system upstream of the compressor - F02M 26/15: in relation to engine exhaust purifying apparatus - F02M 26/24: with two or more coolers - F02M 26/28: with liquid-cooled heat exchangers - F02M 26/37: with temporary storage of recirculated exhaust gas (internal exhaust gas recirculation F02M26/01) - Y02T 10/12: Improving ICE efficiencies - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract In an exhaust gas heat exchanger for a system where a compressing means is located upstream of an internal combustion engine, and a part of exhaust gas from the internal combustion engine flows into the intake gas at a merge part located upstream of the compressing means, the exhaust gas heat exchanger includes a heat exchanging member. The heat exchanging member is provided adjacently to the merge part, and exchanges heat between the intake gas and the part of the exhaust gas such that the part of the exhaust gas is cooled by the intake gas. ## Claims ### Claim 1 An exhaust gas heat exchanger for a system where means for compressing intake air-gas mixture is located upstream of an internal combustion engine and a part of exhaust gas discharged from the internal combustion engine flows into the intake air-gas mixture upstream of the compressing means, the exhaust gas heat exchanger comprising: a heat exchanging member defining an internal passage through which the part of the exhaust gas flows, the heat exchanging member being disposed within an intake pipe through which the intake air-gas mixture flows; an inflow pipe attached to the heat exchanging member, the inflow pipe introducing the part of the exhaust gas into the internal passage; an outflow pipe attached to the heat exchanging member, the outflow pipe introducing the part of the exhaust gas from the internal passage into the inflow pipe; and a discharge pipe attached to the heat exchanging member, the discharge pipe extending through the inflow pipe to discharge a condensate from the internal passage; wherein the heat exchanging member exchanges heat between the part of the exhaust gas in the internal passage and the intake air-gas mixture flowing across an outer surface of the heat exchanging member. ### Claim 2 (depends on 1) The exhaust gas heat exchanger according to claim 1, further comprising: an exhaust gas cooling heat exchanger located upstream of the heat exchanging member, the exhaust gas cooling heat exchanger cooling the part of the exhaust gas by exchanging heat between the part of the exhaust gas and a coolant used for cooling the engine. ### Claim 3 (depends on 1) The exhaust gas heat exchanger according to claim 1, wherein: the discharge passage extends downwardly from a lower end portion of the passage to communicate with the exterior. ### Claim 4 (depends on 3) The exhaust gas heat exchanger according to claim 3, further comprising an on-off valve that is located at a lower end portion of the discharge pipe, wherein the on-off valve is opened and closed based on a weight of the condensate, which is generated when the part of the exhaust gas is cooled. ### Claim 5 (depends on 3) The exhaust gas heat exchanger according to claim 3, further comprising a storing member that is located at a lower end portion of the discharge pipe, wherein the storing member stores the condensate, which is generated when the part of the exhaust gas is cooled. ### Claim 6 (depends on 1) The exhaust gas heat exchanger according to claim 1, wherein: the system further includes a cooling heat exchanger that is located downstream of the compressing means to cool the compressed intake air-gas mixture, which is compressed by the compressing means; the cooled intake air-gas mixture, which is cooled by the cooling heat exchanger, is introduced to the internal combustion engine; and the part of the exhaust gas discharged from the internal combustion engine flows into the intake air-gas mixture at the merge part. ### Claim 7 (depends on 6) The exhaust gas heat exchanger according to claim 6, wherein: the cooling heat exchanger for cooling the intake air-gas mixture is made of aluminum. ### Claim 8 (depends on 1) The exhaust gas heat exchanger according to claim 1, wherein: the heat exchanging member includes an outer tube and an inner tube that is inserted into the outer tube; and the outer tube and the inner tube define therebetween the internal passage, through which the part of the exhaust gas flows. ### Claim 9 (depends on 1) The exhaust gas heat exchanger according to claim 1, wherein: the intake air-gas mixture flows through the inflow pipe in a first direction; and the part of the exhaust gas flows through the heat exchanging member in a second direction opposite from the first direction.