# US 9,518,545 B2 · Method and device for operating 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 9,518,545 B2 - Document ID: US9518545B2 - Status: Granted - Kind: B2 - Application number: 14/427,506 - Filed: 2013-10-04 - Published: 2015-09-03 - Granted: 2016-12-13 - Earliest claimed: 2012-10-11 - Assignees: Continental Automotive GmbH - Applicants: Continental Automotive GmbH - Inventors: Michael Wirkowski; Christian Mey; Christoph Klesse - Web page: https://patentgrep.com/patent/US9518545B2 ## CPC - F02M 59/12: having other positive-displacement pumping elements, e.g. rotary - F02D 41/062: {for starting (F02D41/061 takes precedence)} - F02D 41/3836: {Controlling the fuel pressure} - F02D 41/3845: {by controlling the flow into the common rail, e.g. the amount of fuel pumped} - F02M 39/02: Arrangements of fuel-injection apparatus to facilitate the driving of pumps; Arrangements of fuel-injection pumps; Pump drives - F02M 51/04: Pumps peculiar thereto - F02M 59/102: {Mechanical drive, e.g. tappets or cams (F02M45/063 takes precedence)} - F02M 59/42: for starting of engines {(supply of excess fuel F02M59/447)} - F02M 63/0265: {Pumps feeding common rails} - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - 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) ## Abstract An internal combustion engine has a pressure accumulator, a high-pressure pump, a controllable actuator, and camshaft. The high-pressure pump includes a pump piston movably arranged in a cylinder chamber. The pump piston is supported on the camshaft and thus influences an open volume of the cylinder chamber depending on a rotation of the camshaft. The cylinder chamber is hydraulically coupled to the pressure accumulator to pump the fluid into the pressure accumulator. The actuator drives the camshaft such that the camshaft rotates about the camshaft's longitudinal axis in a specified angular range. The high-pressure pump is controlled prior to an expected motor start such that the high-pressure pump is in a self-priming operating state and the actuator is controlled such that the camshaft rotates about the camshaft longitudinal axis in the specified angular range at least once in a first direction and at least once in an opposite second direction. ## Claims ### Claim 1 A method for operating an internal combustion engine including a pressure accumulator, a high-pressure pump, a controllable actuator and a rotatably mounted camshaft with a longitudinal axis, wherein (a) the high-pressure pump has a cylinder chamber and a pump piston arranged movably in the cylinder chamber and which is at least indirectly supported on the camshaft and thereby influences a free volume of the cylinder chamber based on a rotation of the camshaft, (b) the cylinder chamber of the high-pressure pump is hydraulically coupled to a pressure accumulator at least indirectly to deliver the fluid into the pressure accumulator, and (c) the actuator is configured to drive the camshaft such that the camshaft rotates in a first direction or in an opposite second direction in a predefined angle range about the longitudinal axis, wherein the method comprises: during a predefined time period prior to an expected engine start, activating the high-pressure pump to adopt a self-priming operating state, and during the predefined time period, activating the actuator such that the camshaft rotates at least once in the first direction and at least once in the second direction in the predefined angle range about the longitudinal axis. ### Claim 2 (depends on 1) The method of claim 1, wherein the predefined time period is immediately prior to the expected engine start. ### Claim 3 (depends on 1) The method of claim 1, comprising, during the predefined time period, activating the actuator such that the camshaft rotates initially in the first direction and subsequently in the second direction in the predefined angle range about its longitudinal axis several times until a predefined injection enable pressure in the pressure accumulator is reached. ### Claim 4 (depends on 1) The method of claim 1, wherein the internal combustion engine has a variable valve drive and the camshaft is coupled to at least one of a gas inlet valve and a gas outlet valve of a combustion chamber of the internal combustion engine, and wherein the actuator is configured to control at least one of an opening time and a closing time of the gas inlet valve or gas outlet valve by at least one of driving and adjusting the camshaft. ### Claim 5 (depends on 4) The method of claim 4, wherein the variable valve drive has an electric variable valve drive. ### Claim 6 (depends on 1) The method of claim 1, wherein the high-pressure pump comprises a digitally switching high-pressure pump. ### Claim 7 A device for operating an internal combustion engine including a pressure accumulator, a high-pressure pump, a controllable actuator and a rotatably mounted camshaft with a longitudinal axis, wherein (a) the high-pressure pump has a cylinder chamber and a pump piston arranged movably in the cylinder chamber and which is at least indirectly supported on the camshaft and thereby influences a free volume of the cylinder chamber based on a rotation of the camshaft, (b) the cylinder chamber of the high-pressure pump is hydraulically coupled to a pressure accumulator at least indirectly to deliver the fluid into the pressure accumulator, and (c) the actuator is configured to drive the camshaft such that the camshaft rotates in a first direction or in an opposite second direction in a predefined angle range about the longitudinal axis, wherein the devices is configured to: during a predefined time period to an expected engine start, activate the high-pressure pump to adopt a self-priming operating state, and during the predefined time period, activate the actuator such that the camshaft rotates at least once in the first direction and at least once in the second direction in the predefined angle range about the longitudinal axis. ### Claim 8 (depends on 7) The device of claim 7, wherein the predefined time period is immediately prior to the expected engine start. ### Claim 9 (depends on 7) The device of claim 7, further configured to, during the predefined time period, activate the actuator such that the camshaft rotates initially in the first direction and subsequently in the second direction in the predefined angle range about its longitudinal axis several times until a predefined injection enable pressure in the pressure accumulator is reached. ### Claim 10 (depends on 7) The device of claim 7, wherein the internal combustion engine has a variable valve drive and the camshaft is coupled to at least one of a gas inlet valve and a gas outlet valve of a combustion chamber of the internal combustion engine, and wherein the actuator is configured to control at least one of an opening time and a closing time of the gas inlet valve or gas outlet valve by at least one of driving and adjusting the camshaft. ### Claim 11 (depends on 10) The device of claim 10, wherein the variable valve drive has an electric variable valve drive. ### Claim 12 (depends on 7) The device of claim 7, wherein the high-pressure pump comprises a digitally switching high-pressure pump. ### Claim 13 An internal combustion engine, comprising: a pressure accumulator, a high-pressure pump, a controllable actuator, a rotatably mounted camshaft with a longitudinal axis, wherein the high-pressure pump has a cylinder chamber and a pump piston arranged movably in the cylinder chamber and which is at least indirectly supported on the camshaft and thereby influences a free volume of the cylinder chamber based on a rotation of the camshaft, wherein the cylinder chamber of the high-pressure pump is hydraulically coupled to a pressure accumulator at least indirectly to deliver the fluid into the pressure accumulator, and wherein the actuator is configured to drive the camshaft such that the camshaft rotates in a first direction or in an opposite second direction in a predefined angle range about the longitudinal axis, and a controller configured to: during a predefined time period prior to an expected engine start, activate the high-pressure pump to adopt a self-priming operating state, and during the predefined time period, activate the actuator such that the camshaft rotates at least once in the first direction and at least once in the second direction in the predefined angle range about the longitudinal axis. ### Claim 14 (depends on 13) The internal combustion engine of claim 13, wherein the predefined time period is immediately prior to the expected engine start. ### Claim 15 (depends on 13) The internal combustion engine of claim 13, wherein the controller is configured to, during the predefined time period, activate the actuator such that the camshaft rotates initially in the first direction and subsequently in the second direction in the predefined angle range about its longitudinal axis several times until a predefined injection enable pressure in the pressure accumulator is reached. ### Claim 16 (depends on 13) The internal combustion engine of claim 13, wherein the internal combustion engine has a variable valve drive and the camshaft is coupled to at least one of a gas inlet valve and a gas outlet valve of a combustion chamber of the internal combustion engine, and wherein the actuator is configured to control at least one of an opening time and a closing time of the gas inlet valve or gas outlet valve by at least one of driving and adjusting the camshaft. ### Claim 17 (depends on 16) The internal combustion engine of claim 16, wherein the variable valve drive has an electric variable valve drive. ### Claim 18 (depends on 13) The internal combustion engine of claim 13, wherein the high-pressure pump comprises a digitally switching high-pressure pump.