# US 5,325,666 A · Exhaust system of an 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 5,325,666 A - Document ID: US5325666A - Status: Granted - Kind: A - Application number: 07/975,569 - Filed: 1993-02-04 - Granted: 1994-07-05 - Earliest claimed: 1990-08-04 - Assignees: Dr. Ing. h.c.F. Porsche Aktiengesellschaft - Inventors: Erwin Rutschmann - Web page: https://patentgrep.com/patent/US5325666A ## CPC - F01N 13/04: having two or more silencers in parallel, e.g. having interconnections for multi-cylinder engines - F01N 3/28: Construction of catalytic reactors - F01N 3/2882: {Catalytic reactors combined or associated with other devices, e.g. exhaust silencers or other exhaust purification devices (combined with absorbents or adsorbents only F01N3/0814; combined with particulate filters F01N3/035)} - F01N 3/2889: {with heat exchangers in a single housing} - F01N 5/02: the devices using heat - F01N 13/009: {having two or more separate purifying devices arranged in series} - F01N 13/107: {More than one exhaust manifold or exhaust collector} - F01N 2250/00: Combinations of different methods of purification - Y02T 10/12: Improving ICE efficiencies - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract The exhaust gases of a two-bank internal-combustion engine are guided, by way of exhaust gas collectors, to a central expansion chamber of a housing. From there, they flow through main catalysts arranged on opposite ends of the housing, before they are guided into the open air by way of end mufflers. This exhaust system provides a space-saving arrangement of all components required for an optimal emission control, and low exhaust gas back pressure, and meets all acoustic requirements. ## Claims ### Claim 1 An exhaust system of a multi-cylinder internal-combustion engine, the exhaust gases of which are guided by means of a collector approximately centrally to a housing which has catalysts at opposite ends, all exhaust gas being led out to the open air downstream of the catalysts, wherein the collector is provided with an end piece which projects into an expansion chamber which is centrally arranged in the housing, said end piece being provided with radial openings on its lateral surface. ### Claim 2 (depends on 1) A system according to claim 1, comprising cylinders combined in two banks and exhaust pipes leading from the cylinders to the collector, wherein a collector is assigned to each cylinder bank and leads by means of an end piece into the expansion cylinder, each said end piece being provided with radial openings on its lateral surface. ### Claim 3 (depends on 1) A system according to claim 1, wherein the housing extends transversely with respect to the longitudinal direction (F) of the internal-combustion engine. ### Claim 4 (depends on 1) A system according to claim 1, wherein the expansion chamber is cylindrically constructed, and wherein the end pieces lead perpendicularly into the cylindrically constructed expansion chamber. ### Claim 5 (depends on 2) A system according to claim 2, wherein the end pieces are closed at the end. ### Claim 6 (depends on 2) A system according to claim 2, wherein each exhaust gas collector has a catalyst. ### Claim 7 (depends on 6) A system according to claim 6, wherein each starting catalyst has a closable central duct and a ring duct which surrounds it and contains the catalyst material. ### Claim 8 (depends on 1) A system according to claim 1, wherein the housing is constructed in a double-walled manner as a heat exchanger provided with connection pieces which heats fresh air means of the thermal energy of the exhaust gases. ### Claim 9 (depends on 2) A system according to claim 2, wherein a wall bounding partial chambers is arranged in the expansion chamber between the end pieces. ### Claim 10 (depends on 1) A system according to claim 1, wherein lambda probes are arranged upstream of at least one catalyst. ### Claim 11 (depends on 2) A system according to claim 2, wherein the catalysts include at least one starting catalyst and at least one main catalyst, and wherein lambda probes are arranged upstream of each starting catalyst and downstream of each main catalyst and in the expansion chamber. ### Claim 12 (depends on 2) A system according to claim 2, wherein a separate starting catalyst is assigned to each exhaust pipe. ### Claim 13 (depends on 4) A system according to claim 4, wherein each exhaust gas collector has a catalyst. ### Claim 14 (depends on 5) A system according to claim 5, wherein each exhaust gas collector has a catalyst. ### Claim 15 (depends on 4) A system according to claim 4, wherein lambda probes are arranged upstream of at least one catalyst. ### Claim 16 (depends on 6) A system according to claim 6, wherein lambda probes are arranged upstream of at least one catalyst. ### Claim 17 (depends on 4) A system according to claim 4, wherein the catalysts include at least one starting catalyst and at least one main catalyst, and wherein lambda probes are arranged upstream of each starting catalyst and downstream of each main catalyst and in the expansion chamber. ### Claim 18 (depends on 4) A system according to claim 4, wherein the catalysts include starting catalysts, and wherein a separate starting catalyst is assigned to each exhaust pipe. ### Claim 19 (depends on 1) A system according to claim 1, wherein lambda probes are arranged downstream of at least one catalyst. ### Claim 20 (depends on 4) A system according to claim 4, wherein lambda probes are arranged downstream of at least one catalyst. ### Claim 21 (depends on 6) A system according to claim 6, wherein lambda probes are arranged downstream of at least one catalyst. ### Claim 22 An exhaust system of a multi-cylinder internal-combustion engine, the exhaust gases of which are guided by means of a collector approximately centrally to a housing which has catalysts at opposite ends, all exhaust gas being led out to the open air downstream of the catalysts, wherein the collector is provided with an end piece which projects into an expansion chamber which is centrally arranged in the housing, and wherein lambda probes are arranged upstream of at least one catalyst. ### Claim 23 An exhaust system of a multi-cylinder internal-combustion engine, the exhaust gases of which are guided by means of a collector approximately centrally to a housing which has catalysts at opposite ends, all exhaust gas being led out to the open air downstream of the catalysts, wherein the collector is provided with an end piece which projects into an expansion chamber which is centrally arranged in the housing, and wherein lambda probes are arranged upstream of at least one catalyst.