# US 2014/0190458 A1 · EGR Rate Control For Internal Combustion Engine With Dual Exhaust-Ported Cylinders > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0190458 A1 - Document ID: US20140190458A1 - Status: Published application - Kind: A1 - Application number: 13/736,271 - Filed: 2013-01-08 - Published: 2014-07-10 - Earliest claimed: 2013-01-08 - Assignees: Southwest Research Institute - Inventors: Jess W. Gingrich; Raphael Gukelberger - Web page: https://patentgrep.com/patent/US20140190458A1 ## CPC - F02B 47/08: the substances including exhaust gas - F01N 13/107: {More than one exhaust manifold or exhaust collector} - F02D 13/0246: {changing valve lift or valve lift and timing} - F02D 13/0257: {Independent control of two or more intake or exhaust valves respectively, i.e. one of two intake valves remains closed or is opened partially while the other is fully opened} - F02D 41/005: {according to engine operating conditions} - F02D 41/0065: {Specific aspects of external EGR control (constructional details of EGR system F02M26/00)} - F02D 41/008: {Controlling each cylinder individually} - F02M 26/43: in which exhaust from only one cylinder or only a group of cylinders is directed to the intake of the engine - F02M 26/05: High pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust system upstream of the turbine and reintroduced into the intake system downstream of the compressor - Y02T 10/12: Improving ICE efficiencies - Y02T 10/40: Engine management systems - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) - 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) - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A method of using exhaust gas recirculation (EGR) in an internal combustion engine. At least two of the cylinders are “dual exhaust-ported cylinders” having two exhaust ports. For each of these cylinders, one of the exhaust ports is connected to the EGR loop and the other of the exhaust ports is connected to the main exhaust line. These cylinders are controlled such that one exhaust port is open and the other exhaust port is closed during each engine cycle, and are operated, on a cycle-by-cycle basis so that all of the exhaust produced by a cylinder may be delivered to the EGR loop at any cycle. The number of cylinders operating as EGR cylinders per engine cycle is in response to a desired EGR rate. ## Claims ### Claim 1 A method of using exhaust gas recirculation (EGR) in an internal combustion engine having a number of cylinders, at least two of the cylinders being “dual exhaust-ported cylinders” having two exhaust ports, the engine further having an EGR loop and a main exhaust line, comprising: for at least two dual exhaust-ported cylinders, connecting, via exhaust valves, one of the exhaust ports to the EGR loop and the other of the exhaust ports to the main exhaust line; controlling the at least two dual exhaust-ported cylinders on a cycle-by-cycle basis, such that for any engine cycle, one exhaust valve may be opened and the other exhaust valve may be closed; determining, for a selected engine cycle, whether at least one of the dual exhaust-ported cylinders is to be operated as an EGR cylinder, such that all of the exhaust produced by that cylinder is delivered to the EGR loop; and repeating the operating step for successive engine cycles, such that the number of cylinders operated as an EGR cylinder may vary from cycle to cycle; wherein the number of cylinders operating as EGR cylinders per engine cycle and the frequency of operation of any cylinder as an EGR cylinder are in response to one or more desired EGR rates. ### Claim 2 (depends on 1) The method of claim 1, wherein the operating step is performed by operating the at least one EGR cylinder at a different air-fuel ratio than the other cylinders. ### Claim 3 (depends on 1) The method of claim 1, wherein the operating step is performed by operating the at least one EGR cylinder at a richer air-fuel ratio than the other cylinders. ### Claim 4 (depends on 1) The method of claim 1, wherein the engine is a spark ignited engine. ### Claim 5 (depends on 1) The method of claim 1, wherein the engine is a compression ignited engine. ### Claim 6 (depends on 1) The method of claim 1, wherein all of the engine cylinders are dual exhaust-ported cylinders, and all or a subset of the cylinders are operated as EGR cylinders for selected engine cycles. ### Claim 7 (depends on 1) The method of claim 1, wherein all of the engine cylinders are dual exhaust-ported cylinders, and a subset of the cylinders have both exhaust ports connected to the main exhaust line. ### Claim 8 (depends on 1) The method of claim 1, wherein all of the engine cylinders are dual exhaust-ported cylinders, and all cylinders are connected to both the EGR loop and the main exhaust line via the exhaust valves. ### Claim 9 (depends on 1) The method of claim 1, wherein the operating step is performed for at least one dual exhaust-ported cylinder for all engine cycles. ### Claim 10 An improved dual exhaust-ported internal combustion engine, the engine having multiple cylinders, an EGR loop and a main exhaust line, comprising: at least two dual exhaust-ported cylinders having two exhaust ports; wherein, for the at least two dual exhaust-ported cylinders, one of the exhaust ports is connected, via an EGR exhaust valve, to the EGR loop and the other of the exhaust ports is connected, via a main exhaust valve, to the main exhaust line; memory for storing EGR rate data that provides desired EGR rates in response to input data representing engine operating conditions; a control unit programmed to control each dual exhaust-ported cylinder such that one exhaust port is open and the other exhaust port is closed during each engine cycle; to control each dual exhaust-ported cylinder on a cycle-by-cycle basis, such that for any engine cycle, one exhaust valve may be opened and the other exhaust valve may be closed; and to generate control signals for operating, for selected engine cycles, any or none of the dual exhaust-ported cylinders as an EGR cylinder whose entire exhaust is delivered to the EGR loop; wherein the number of cylinders operating as EGR cylinders per engine cycle is in response to a current desired EGR rate. ### Claim 11 (depends on 10) The system of claim 10, wherein the engine is a spark ignited engine. ### Claim 12 (depends on 10) The system of claim 10, wherein the engine is a compression ignited engine. ### Claim 13 (depends on 10) The system of claim 10, wherein all of the engine cylinders are dual exhaust-ported cylinders, and all or a subset of the cylinders are operated as EGR cylinders for selected engine cycles. ### Claim 14 (depends on 10) The system of claim 10, wherein all of the engine cylinders are dual exhaust-ported cylinders, and a subset of the cylinders have both exhaust ports connected to the main exhaust line. ### Claim 15 (depends on 10) The system of claim 10, wherein all of the engine cylinders are dual exhaust-ported cylinders, and all cylinders are connected to both the EGR loop and the main exhaust line via the exhaust valves.