# US 7,610,897 B2 · Valvetrain control systems for internal combustion engines with time and event based control > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,610,897 B2 - Document ID: US7610897B2 - Status: Granted - Kind: B2 - Application number: 12/062,938 - Filed: 2008-04-04 - Published: 2009-03-12 - Granted: 2009-11-03 - Earliest claimed: 2007-09-07 - Assignees: GM Global Technology Operations LLC - Inventors: Allen B. Rayl - Web page: https://patentgrep.com/patent/US7610897B2 ## CPC - F01L 1/185: {Overhead end-pivot rocking arms} - F01L 13/0036: {the valves being driven by two or more cams with different shape, size or timing or a single cam profiled in axial and radial direction} - F02D 13/0207: {changing valve lift or valve lift and timing} - F01L 1/2405: {by means of a hydraulic adjusting device located between the cylinder head and rocker arm} - F01L 1/34: characterised by the provision of means for changing the timing of the valves without changing the duration of opening {and without affecting the magnitude of the valve lift} - F01L 2303/01: Tools for producing, mounting or adjusting, e.g. some part of the distribution - F01L 2305/00: Valve arrangements comprising rollers - F01L 2800/00: Methods of operation using a variable valve timing mechanism - F01L 2800/13: Throttleless - F01L 2820/041: Camshafts position or phase sensors - F01L 2820/042: Crankshafts position - F02D 41/3035: {a mode being the premixed charge compression-ignition mode} - F02D 2041/001: {for engines with variable valve actuation} - F02D 2250/21: during a transition between engine operation modes or states - Y02T 10/12: Improving ICE efficiencies - F01L: CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES - 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) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A valve control system includes a vehicle control module that generates a lift mode command signal to transition one of intake and exhaust valves between N open lift modes. A time module generates a response time signal that indicates a duration of the transition and a lift limit signal that disables the transition. The time module generates the response time and lift limit signals based on current lift mode and status signals. The current lift mode signal indicates a current lift state of one of the intake and exhaust valves. The status signal indicates status of a lift control valve. The lift control valve actuates one of the intake valve and the exhaust valve. The event module generates the current lift mode and status signals based on the lift command signal, the response time signal, and the lift limit signal. One of the time and event modules enables the transition. ## Claims ### Claim 1 A valve control system for an internal combustion engine comprising: a vehicle control module that generates a lift mode command signal to transition at least one of an intake valve and an exhaust valve between N open lift modes, where N is an integer greater than one; a time module that generates a response time signal that indicates a duration for performing said transition and a lift limit signal that disables said transition, wherein said time module generates said response time signal and said lift limit signal based on a current lift mode signal that indicates a current lift state of at least one of said intake valve and said exhaust valve and a status signal that indicates status of a lift control valve that actuates at least one of said intake valve and said exhaust valve; and an event module generates said current lift mode signal and said status signal based on said lift command signal, said response time signal, and said lift limit signal, wherein at least one of said time and event modules enables said transition. ### Claim 2 (depends on 1) The valve control system of claim 1 wherein said event module generates said current lift mode signal and said status signal based on a set of sensor signals. ### Claim 3 (depends on 2) The valve control system of claim 2 wherein said set of sensor signals comprise at least one of a crank angle signal, a cylinder identification signal, an intake camshaft position signal, and an exhaust camshaft position signal. ### Claim 4 (depends on 1) The valve control system of claim 1 wherein said time module enables said transition based on an intake and exhaust valve based switching window, and wherein said switching window has a start time associated with opening of an intake valve and an end time associated with opening of an exhaust valve. ### Claim 5 (depends on 1) The valve control system of claim 1 wherein time module enables said transition based on an intake and exhaust valve based switching window, and wherein said control module changes open lift mode of at least one of said intake and exhaust valves based on said switching window. ### Claim 6 (depends on 5) The valve control system of claim 5 wherein said time module prevents said transition when response time to switch between said N open lift modes is greater than duration of said switching window. ### Claim 7 (depends on 1) The valve control system of claim 1 wherein said time module determines duration of a switching window associated with said intake and exhaust valves, and wherein said time module switches between open lift modes based on said duration. ### Claim 8 (depends on 1) The valve control system of claim 1 wherein said vehicle control module switches said intake and exhaust valves via different lift control valves. ### Claim 9 (depends on 1) The valve control system of claim 1 wherein said time module determines a position in time of a switching window associated with said intake and exhaust valves relative to crankshaft timing, and wherein said time module switches between said N open lift modes based on said position. ### Claim 10 (depends on 1) The valve control system of claim 1 wherein said control module determines a target angle for switching between open lift modes based on at least one of a switching window start time, a switching window end time, an offset from a switching window start time, an offset from a switching window end time, and a percentage of switching window duration. ### Claim 11 (depends on 1) The valve control system of claim 1 wherein said control module synchronizes lift mode control of said intake and exhaust valves to a position of a crankshaft and to valvetrain timing, and wherein said control module generates a engine position synchronization flag when a transition between said open lift modes occurs. ### Claim 12 (depends on 1) The valve control system of claim 1 further comprising a cylinder event counter, wherein said event module accounts for a lift control valve response time that is longer than one engine cycle via said cylinder event counter. ### Claim 13 (depends on 1) The valve control system of claim 1 wherein said time module generates said response time signal and said lift limit signal based on a set of sensor signals. ### Claim 14 (depends on 13) The valve control system of claim 13 wherein said set of sensor signals comprise at least one of a power supply signal, an oil pressure signal, an oil temperature signal and a coolant temperature signal. ### Claim 15 (depends on 14) The valve control system of claim 14 further comprising an oil pressure conversion module that generates a valve control oil pressure signal of at least one of an intake valve assembly and an exhaust valve assembly based on an engine oil pressure signal. ### Claim 16 (depends on 15) The valve control system of claim 15 wherein said conversion is based on and engine oil temperature. ### Claim 17 (depends on 15) The valve control system of claim 15 wherein said conversion is based on number of oil pressure control valves associated with at least one of said intake and exhaust valve assemblies. ### Claim 18 (depends on 15) The valve control system of claim 15 wherein said control module prevents said transitioning when said oil pressure signal is approximately less than or equal to 200 kpa. ### Claim 19 (depends on 15) The valve control system of claim 15 wherein said conversion is based on number of lift control valves associated with lift position control of at least one of said intake and exhaust valves. ### Claim 20 (depends on 14) The valve control system of claim 14 wherein said open lift modes include a HIGH lift mode and a LOW lift mode, and wherein said control module prevents operating in said LOW lift mode based on said oil pressure signal. ### Claim 21 (depends on 14) The valve control system of claim 14 wherein said control module prevents said transitioning when said oil pressure signal exceeds a predetermined limit. ### Claim 22 (depends on 14) The valve control system of claim 14 wherein said control module prevents said transitioning for both said intake and exhaust valves based on said oil pressure signal. ### Claim 23 (depends on 14) The valve control system of claim 14 comprising: a time module that generates a lift limit signal based on said oil pressure signal; and an event module that prevents said transitioning based on said lift limit signal. ### Claim 24 (depends on 14) The valve control system of claim 14 wherein said conversion device generates an intake valve control oil pressure signal of an intake valve assembly and an exhaust valve control oil pressure signal of an exhaust valve assembly based on said oil pressure signal. ### Claim 25 (depends on 14) The valve control system of claim 14 wherein said control module prevents transitioning based on a lift mode command signal. ### Claim 26 (depends on 14) The valve control system of claim 14 wherein said control module estimates a manifold oil pressure based on a galley oil pressure, and wherein said control module enables said transitioning based on said manifold oil pressure. ### Claim 27 (depends on 1) The valve control system of claim 1 wherein said control module estimates a manifold temperature based on lift control valve on time. ### Claim 28 (depends on 14) The valve control system of claim 14 wherein said valve actuation system actuates each of an intake valve and an exhaust valve between said plurality of different open lift modes.