# US 10,480,438 B2 · Fuel injection control device for direct injection engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,480,438 B2 - Document ID: US10480438B2 - Status: Granted - Kind: B2 - Application number: 15/557,987 - Filed: 2016-03-16 - Published: 2018-03-22 - Granted: 2019-11-19 - Earliest claimed: 2015-03-23 - Assignees: Mazda Motor Corporation - Applicants: Mazda Motor Corporation - Inventors: Takeshi Nagasawa; Keiji Araki; Noriyuki Ota; Kenji Uchida; Ryohei Ono; Kiyotaka Sato; Hidefumi Fujimoto - Web page: https://patentgrep.com/patent/US10480438B2 ## CPC - F02D 41/06: for engine starting or warming up {(F02D41/0255 takes precedence)} - F02B 17/005: {having direct injection in the combustion chamber} - F02B 23/101: {the injector being placed on or close to the cylinder centre axis, e.g. with mixture formation using spray guided concepts} - F02D 13/02: during engine operation - F02D 21/08: the other gas being the exhaust gas of engine - F02D 41/0002: {Controlling intake air} - F02D 41/024: {to increase temperature of the exhaust gas treating apparatus} - F02D 41/04: Introducing corrections for particular operating conditions (F02D41/14 takes precedence) - F02D 41/068: {for warming-up} - F02D 41/401: {Controlling injection timing (F02D41/402 takes precedence)} - F02D 41/402: {Multiple injections} - F02D 2041/389: {for injecting directly into the cylinder} - F02D 2200/021: Engine temperature - Y02T 10/12: Improving ICE efficiencies - Y02T 10/40: Engine management systems - 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) - 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 Disclosed herein is a fuel injection control device for a direct injection engine including an engine body (engine 1) and a fuel injection control unit (engine controller 100). The fuel injection control unit injects a fuel in a predetermined injection mode into a combustion chamber (17) such that while the engine body is warm, an air-fuel mixture layer and a heat-insulating gas layer, surrounding the air-fuel mixture layer, are formed in the combustion chamber at a point in time when an air-fuel mixture ignites, and changes the injection mode of the fuel into the combustion chamber such that while the engine body is cold, the lower the temperature of the engine body is, the thinner the heat-insulating gas layer becomes. ## Claims ### Claim 1 A fuel injection control device for a direct injection engine, the control device comprising: an engine body including a combustion chamber defined by a cylinder head ceiling portion, a cylinder provided for a cylinder block, and a piston reciprocating inside the cylinder; and a fuel injection control unit which includes a fuel injection valve, provided inside the combustion chamber to inject a liquid fuel, and which is configured to inject the fuel into the combustion chamber at a predetermined timing, wherein the fuel injection control unit is configured to inject the fuel in a predetermined injection mode into the combustion chamber such that while the engine body is in a warm state where the temperature of the engine body has reached or exceeded a predetermined temperature, an air-fuel mixture layer and a heat-insulating gas layer, surrounding the air-fuel mixture layer, are formed in the combustion chamber at a point in time when an air-fuel mixture ignites, change the injection mode of the fuel into the combustion chamber such that while the engine body is in a cold state where the temperature of the engine body is less than the predetermined temperature, the lower the temperature of the engine body is, the thinner the heat-insulating gas layer becomes, the fuel injection control unit performs discrete injections including a plurality of fuel injections, and sets an interval between two successive injections of the discrete injections to be shorter while the engine body is cold than while the engine body is warm. ### Claim 2 (depends on 1) The fuel injection control device for the direct injection engine of claim 1, further comprising a catalyst device arranged on an exhaust passage of the engine body and configured to purify an exhaust gas exhausted from the combustion chamber, wherein the fuel injection control unit is configured to change the injection mode of the fuel into the combustion chamber such that while the catalyst device is active and the engine body is cold, the lower the temperature of the engine body is, the thinner the heat-insulating gas layer becomes, and inject the fuel in a predetermined injection mode into the combustion chamber such that the heat-insulating gas layer becomes thicker while the catalyst device is inactive and the engine body is cold than while the catalyst device is active and the engine body is cold. ### Claim 3 (depends on 2) The fuel injection control device for the direct injection engine of claim 2, wherein the fuel injection control unit is configured to retard an injection start timing of the fuel to a predetermined timing such that while the catalyst device is inactive and the engine body is cold, the heat-insulating gas layer thickens, and advance the injection start timing of the fuel while the catalyst device is active and the engine body is cold with respect to the injection start timing while the catalyst device is inactive and the engine body is cold. ### Claim 4 (depends on 3) The fuel injection control device for the direct injection engine of claim 3, further comprising an air volume adjuster configured to adjust the volume of air introduced into the cylinder, wherein the air volume adjuster decreases the volume of the air introduced into the cylinder, and thereby brings a fuel-air equivalence ratio of a gas in the combustion chamber closer to one, while the catalyst device is inactive and the engine body is cold than while the engine body is warm. ### Claim 5 (depends on 2) The fuel injection control device for the direct injection engine of claim 2, further comprising an air volume adjuster configured to adjust the volume of air introduced into the cylinder, wherein the air volume adjuster decreases the volume of the air introduced into the cylinder, and thereby brings a fuel-air equivalence ratio of a gas in the combustion chamber closer to one, while the catalyst device is inactive and the engine body is cold than while the engine body is warm. ### Claim 6 (depends on 5) The fuel injection control device for the direct injection engine of claim 5, wherein while the catalyst device is inactive and has a temperature exceeding a predetermined temperature, the air volume adjuster sets the fuel-air equivalence ratio of the air-fuel mixture layer to be equal to or greater than one and sets the fuel-air equivalence ratio of the entire gas in the combustion chamber to be either equal to one or closer to one than when the temperature of the catalyst device is equal to or lower than the predetermined temperature. ### Claim 7 (depends on 6) The fuel injection control device for the direct injection engine of claim 6, wherein the air volume adjuster decreases the volume of the air introduced into the cylinder by introducing a burned gas into the cylinder. ### Claim 8 (depends on 5) The fuel injection control device for the direct injection engine of claim 5, wherein the air volume adjuster decreases the volume of the air introduced into the cylinder by introducing a burned gas into the cylinder. ### Claim 9 A fuel injection control device for a direct injection engine, the control device comprising: an engine body including a combustion chamber defined by a cylinder head ceiling portion, a cylinder provided for a cylinder block, and a piston reciprocating inside the cylinder; a fuel injection control unit which includes a fuel injection valve, provided inside the combustion chamber to inject a liquid fuel, and which is configured to inject the fuel into the combustion chamber at a predetermined timing; and a catalyst device arranged on an exhaust passage of the engine body and configured to purify an exhaust gas exhausted from the combustion chamber, wherein the fuel injection control unit is configured to inject the fuel in a predetermined injection mode into the combustion chamber such that while the engine body is in a warm state where the temperature of the engine body has reached or exceeded a predetermined temperature, an air-fuel mixture layer and a heat-insulating gas layer, surrounding the air-fuel mixture layer, are formed in the combustion chamber at a point in time when an air-fuel mixture ignites, change the injection mode of the fuel into the combustion chamber such that while the engine body is in a cold state where the temperature of the engine body is less than the predetermined temperature, the lower the temperature of the engine body is, the thinner the heat-insulating gas layer becomes, retard an injection start timing of the fuel to a predetermined timing such that while the catalyst device is inactive and the engine body is cold, the heat-insulating gas layer thickens, and advance the injection start timing of the fuel while the catalyst device is active and the engine body is cold with respect to the injection start timing while the catalyst device is inactive and the engine body is cold. ### Claim 10 A fuel injection control device for a direct injection engine, the control device comprising: an engine body including a combustion chamber defined by a cylinder head ceiling portion, a cylinder provided for a cylinder block, and a piston reciprocating inside the cylinder; and a fuel injection control unit which includes a fuel injection valve, provided inside the combustion chamber to inject a liquid fuel, and which is configured to inject the fuel into the combustion chamber at a predetermined timing, wherein the fuel injection control unit is configured to inject the fuel in a predetermined injection mode into the combustion chamber such that while the engine body is in a warm state where the temperature of the engine body has reached or exceeded a predetermined temperature, an air-fuel mixture layer and a heat-insulating gas layer, surrounding the air-fuel mixture layer, are formed in the combustion chamber at a point in time when an air-fuel mixture ignites, and change the injection mode of the fuel into the combustion chamber such that while the engine body is in a cold state where the temperature of the engine body is less than the predetermined temperature, the lower the temperature of the engine body is, the thinner the heat-insulating gas layer becomes, the fuel injection control unit performs discrete injections including a plurality of fuel injections, and sets an interval between two successive injections of the discrete injections to be shorter while the engine body is cold than while the engine body is warm.