# US 11,028,751 B2 · Method of controlling operation of an exhaust gas treatment apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,751 B2 - Document ID: US11028751B2 - Status: Granted - Kind: B2 - Application number: 16/303,335 - Filed: 2017-04-25 - Published: 2020-10-08 - Granted: 2021-06-08 - Earliest claimed: 2016-05-20 - Assignees: Caterpillar Inc. - Applicants: Caterpillar Inc. - Inventors: Antony J. Eager; Ben Darley - Web page: https://patentgrep.com/patent/US11028751B2 ## CPC - F01N 3/2066: {Selective catalytic reduction [SCR]} - F02D 41/025: {by changing the composition of the exhaust gas, e.g. for exothermic reaction on exhaust gas treating apparatus} - F01L 3/02: Selecting particular materials for valve-members or valve-seats; Valve-members or valve-seats composed of two or more materials - F01N 3/021: by means of filters - F01N 3/103: {Oxidation catalysts for HC and CO only} - F02D 41/0245: {by increasing temperature of the exhaust gas leaving the engine} - F02D 41/402: {Multiple injections} - F02D 41/405: {with post injections} - F01L 2301/02: Using ceramic materials - F01N 2610/02: the substance being ammonia or urea - F02D 41/029: {the exhaust gas treating apparatus being a particulate filter} - F02D 2041/389: {for injecting directly into the cylinder} - F02D 2200/0802: Temperature of the exhaust gas treatment apparatus - Y02T 10/12: Improving ICE efficiencies - Y02T 10/40: Engine management systems - 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) - F01L: CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A method of controlling operation of an engine, the engine comprising: a combustion unit having an exhaust conduit and one or more combustion cylinders each having a piston, a fuel injector, an intake valve and an exhaust valve leading to the exhaust conduit; an exhaust gas treatment apparatus configured to receive fluid from the exhaust conduit and comprising a diesel oxidation catalyst module; and a controller configured to receive a temperature data value indicative of a temperature of gas within the diesel oxidation catalyst module. The method comprises: injecting fuel from the fuel injector into each of the one or more combustion cylinders in a main injection event to initiate via compression ignition a primary combustion event that drives the piston. The method further comprises using the controller to compare the temperature data value relative to a first temperature threshold value and a second temperature threshold value. ## Claims ### Claim 1 A method of controlling operation of an engine, the engine comprising: a combustion unit having an exhaust conduit and one or more combustion cylinders each having a piston, a fuel injector, an intake valve and an exhaust valve leading to the exhaust conduit; an exhaust gas treatment apparatus configured to receive fluid from the exhaust conduit and comprising an upstream module and a downstream module; a controller configured to receive a temperature data value indicative of a temperature of gas within the upstream module; the method comprising: injecting fuel from the fuel injector into each of the one or more combustion cylinders in a main injection event to initiate a primary combustion event that drives the piston; and using the controller to compare the temperature data value relative to a first temperature threshold value and a second temperature threshold value; wherein: in an event that the controller determines that the temperature data value is between the first threshold temperature value and the second threshold temperature value, injecting fuel from the fuel injector into one of the one or more combustion cylinders in a subsidiary injection event after the main injection event during a period in which the fuel injected in the subsidiary injection event passes into the upstream module without combusting in the combustion unit; and in an event that the controller determines that the temperature data value is below the first threshold temperature value, injecting fuel from the fuel injector into one of the one or more combustion cylinders in an interim injection event during a period after the main injection event such that fuel injected in the interim injection event results in a secondary combustion event in the combustion unit. ### Claim 2 (depends on 1) The method of claim 1 comprising combustion of the fuel injected in the subsidiary injection event in the upstream module of the exhaust gas treatment apparatus. ### Claim 3 (depends on 1) The method of claim 1 wherein the upstream module of the exhaust gas treatment apparatus comprises a diesel oxidation catalyst. ### Claim 4 (depends on 3) The method of claim 3 wherein the first threshold temperature value corresponds to a minimum temperature at which fuel entering the diesel oxidation catalyst module combusts in the diesel oxidation catalyst module. ### Claim 5 (depends on 1) The method of claim 1 wherein the combustion unit comprises first and second combustion cylinders and wherein the method comprises: the subsidiary injection event comprising injecting fuel into the first combustion cylinder; and the interim injection event comprises injecting fuel into the second combustion cylinder. ### Claim 6 (depends on 1) The method of claim 1 wherein the second temperature threshold value corresponds to a steady state temperature of the exhaust gas treatment apparatus. ### Claim 7 (depends on 1) The method of claim 1 wherein: the exhaust gas treatment apparatus comprises a selective catalytic reduction module and wherein the second threshold temperature value corresponds to or is a function of a minimum prescribed temperature of operation of the selective catalytic reduction module. ### Claim 8 (depends on 1) The method of claim 1 wherein the engine further comprises a glow plug and wherein the method further comprises using the glow plug to ignite the fuel injected in the interim injection event. ### Claim 9 (depends on 1) The method of claim 1 wherein parts of the exhaust valve comprise ceramic. ### Claim 10 (depends on 1) The method of claim 1 further comprising providing a temperature sensor in a vicinity of the diesel oxidation catalyst configured to provide the temperature data value indicative of the temperature of gas within the diesel oxidation catalyst module. ### Claim 11 (depends on 1) The method of claim 1 further comprising: using the controller to receive sensed temperature data from upstream of or downstream of the diesel oxidation catalyst module and use said sensed temperature data to calculate an inferred temperature data value that is indicative of the temperature of gas within the diesel oxidation catalyst module. ### Claim 12 An engine comprising: a combustion unit having an exhaust conduit and one or more combustion cylinders each having a piston, a fuel injector, an intake valve and an exhaust valve leading to the exhaust conduit; an exhaust gas treatment apparatus configured to receive fluid from the exhaust conduit and comprising an upstream module and a downstream module; a controller configured to receive a temperature data value indicative of a temperature of gas within the upstream module; wherein the controlled is configured to: initiate injection of fuel from the fuel injector into each of the one or more combustion cylinders in a main injection event to initiate a primary combustion event that drives the piston; and compare the temperature data value relative to a first temperature threshold value and a second temperature threshold value; wherein: in an event that the controller determines that the temperature data value is between the first threshold temperature value and the second threshold temperature value, to initiate injection of fuel from the fuel injector into one of the one or more combustion cylinders in a subsidiary injection event after the main injection event during a period in which the fuel injected in the subsidiary injection event passes into the upstream module without combusting in the combustion unit; and in an event that the controller determines that the temperature data value is below the first threshold temperature value, to initiate injection of fuel from the fuel injector into one of the one or more combustion cylinders in an interim injection event during a period after the main injection event such that fuel injected in the interim injection event results in a secondary combustion event in the combustion unit. ### Claim 13 (depends on 12) The engine of claim 12 wherein the combustion unit comprises one or more glow plugs or spark plugs. ### Claim 14 (depends on 12) The engine of claim 12 wherein the exhaust valve comprises ceramic. ### Claim 15 (depends on 12) The engine of claim 12 further comprising a temperature sensor in a vicinity of the diesel oxidation catalyst configured to provide the temperature data value indicative of the temperature of gas within the diesel oxidation catalyst module. ### Claim 16 (depends on 1) The method of claim 1 wherein: the exhaust gas treatment apparatus comprises a diesel particulate filter module and wherein the second threshold temperature value corresponds to or is a function of a minimum prescribed temperature for combustion of soot in the diesel particulate filter module. ### Claim 17 (depends on 1) The method of claim 1 wherein: the exhaust gas treatment apparatus comprises emissions fluid injector module for injecting urea containing material and wherein the second threshold temperature value corresponds to or is a function of a minimum prescribed temperature for decomposition of urea deposits that may build up in the vicinity of the emissions fluid injector module. ### Claim 18 (depends on 1) The method of claim 1 further comprising: using measured, inferred, or modelled data in combination with a look-up table or data library to establish the temperature data value that is indicative of the temperature of gas within the diesel oxidation catalyst module.