# US 8,784,264 B2 · Method and system for controlling catalyst temperature > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,784,264 B2 - Document ID: US8784264B2 - Status: Granted - Kind: B2 - Application number: 13/663,723 - Filed: 2012-10-30 - Published: 2014-05-01 - Granted: 2014-07-22 - Earliest claimed: 2012-10-30 - Assignees: Ford Global Technologies, LLC - Applicants: Ford Global Technologies, LLC - Inventors: Alex O'Connor Gibson; Jeffrey Allen Doering; Dennis Graig Reed - Web page: https://patentgrep.com/patent/US8784264B2 ## CPC - B60W 20/16: for reducing engine exhaust emissions - B60K 6/48: Parallel type - B60W 10/02: including control of driveline clutches - B60W 10/06: including control of combustion engines - B60W 10/08: including control of electric propulsion units, e.g. motors or generators - B60W 20/13: in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion - B60W 20/40: Controlling the engagement or disengagement of prime movers, e.g. for transition between prime movers {(power-up or power-down of the driveline B60W30/192)} - F02D 41/0077: {Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position (EGR valve position sensor F02M26/48)} - F02D 41/022: {in relation with the clutch status} - F02N 11/04: the motors being associated with current generators - B60K 2006/4825: {Electric machine connected or connectable to gearbox input shaft} - B60W 2510/068: Engine exhaust temperature - B60W 2510/081: Speed - B60W 2510/244: Charge state - B60W 2540/10: Accelerator pedal position - B60W 2552/15: Road slope, i.e. the inclination of a road segment in the longitudinal direction - B60W 2710/021: Clutch engagement state - B60W 2710/0622: Air-fuel ratio - B60W 2710/0633: Inlet air flow rate - B60W 2710/0644: Engine speed - B60W 2710/0694: Engine exhaust temperature - B60W 2710/083: Torque - B60Y 2200/92: Hybrid vehicles - Y02T 10/62: Hybrid vehicles - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - 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) - F02N: STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR - B60Y: INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A method and a system for improving operation of a hybrid vehicle are presented. In one example, an engine exhaust after treatment device is cooled at an opportunistic time. The approach may provide improved cooling for exhaust after treatment devices and it may also improve vehicle emissions. ## Claims ### Claim 1 A method for operating a hybrid powertrain, comprising: opening a disconnect clutch and limiting a temperature that an exhaust after treatment device reaches via an action in response to a desired torque being less than a threshold torque and an after treatment device temperature. ### Claim 2 (depends on 1) The method of claim 1, further comprising increasing an engine air mass flow and decreasing cylinder air charge per cylinder cycle. ### Claim 3 (depends on 2) The method of claim 2, where the engine air mass flow is increased via increasing engine speed. ### Claim 4 (depends on 1) The method of claim 1, further comprising adjusting an engine air mass flow in response to a time since a desired torque is less than a threshold torque. ### Claim 5 (depends on 1) The method of claim 1, further comprising adjusting an engine air mass flow in response to a road grade. ### Claim 6 (depends on 1) The method of claim 1, further comprising increasing an engine EGR amount. ### Claim 7 A method for operating a hybrid powertrain, comprising: limiting an exhaust after treatment device temperature via a first action in response to a desired torque that is greater a threshold torque; and opening a disconnect clutch and limiting the exhaust after treatment device temperature via a second action in response to the desired torque being less than the threshold torque. ### Claim 8 (depends on 7) The method of claim 7, where the first action includes enriching an engine air-fuel mixture. ### Claim 9 (depends on 7) The method of claim 7, where the first action includes reducing engine air flow to less than a maximum engine air flow. ### Claim 10 (depends on 7) The method of claim 7, where the second action includes increasing engine speed to a value greater than a base engine speed at similar engine operating conditions. ### Claim 11 (depends on 7) The method of claim 7, further comprising closing the disconnect clutch and adjusting an engine air mass flow rate to increase the exhaust after treatment device temperature in response to the exhaust after treatment device temperature being less than a threshold exhaust after treatment device temperature. ### Claim 12 (depends on 7) The method of claim 7, where the second action includes increasing an engine air flow rate to a rate that is greater than a base engine air flow rate at similar engine operating conditions. ### Claim 13 (depends on 12) The method of claim 12, where the similar engine operating conditions are at a same desired torque. ### Claim 14 (depends on 12) The method of claim 12, where the second action further includes reducing a cylinder air charge per cylinder cycle. ### Claim 15 A method for operating a hybrid powertrain, comprising: opening a disconnect clutch and limiting a temperature that an exhaust after treatment device reaches via an action in response to a desired torque being less than a threshold torque and an after treatment device temperature; and supplying the desired torque to a vehicle driveline via a DISG. ### Claim 16 (depends on 15) The method of claim 15, further comprising closing the disconnect clutch in response to a capacity of the DISG to provide the desired torque. ### Claim 17 (depends on 16) The method of claim 16, further comprising operating the engine at a stoichiometric air-fuel ratio after closing the disconnect clutch. ### Claim 18 (depends on 15) The method of claim 15, further comprising increasing an engine air flow. ### Claim 19 (depends on 18) The method of claim 18, further comprising decreasing a cylinder air charge per cylinder cycle. ### Claim 20 (depends on 15) The method of claim 15, further comprising adjusting a DISG torque output in response to the desired torque.