# US 9,435,245 B2 · Exhaust gas purification device for 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 9,435,245 B2 - Document ID: US9435245B2 - Status: Granted - Kind: B2 - Application number: 14/416,145 - Filed: 2013-02-15 - Published: 2015-12-03 - Granted: 2016-09-06 - Earliest claimed: 2013-02-15 - Assignees: Toyota Jidosha Kabushiki Kaisha - Applicants: Ryohei Ono - Inventors: Ryohei Ono - Web page: https://patentgrep.com/patent/US9435245B2 ## CPC - F01N 3/36: Arrangements for supply of additional fuel - B01D 53/9431: {Processes characterised by a specific device} - B01D 53/9495: {Controlling the catalytic process} - F01N 3/0842: {Nitrogen oxides} - F01N 3/0871: {using means for controlling, e.g. purging, the absorbents or adsorbents} - F01N 3/0885: {Regeneration of deteriorated absorbents or adsorbents, e.g. desulfurization of NOx traps} - F01N 9/00: Electrical control of exhaust gas treating apparatus (monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00; conjoint electrical control of two or more combustion engine functions F02D43/00) - F01N 9/002: {of filter regeneration} - F01N 2470/18: the axis of inlet or outlet tubes being other than the longitudinal axis of apparatus - F01N 2560/08: the means being a pressure sensor - F01N 2560/14: having more than one sensor of one kind - F01N 2610/03: the substance being hydrocarbons, e.g. engine fuel - F01N 2610/1453: Sprayers or atomisers; Arrangement thereof in the exhaust apparatus - 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) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An internal combustion engine is configured in such a manner that an exhaust gas purification catalyst (13) and a hydrocarbon supply valve (15) are provided in an exhaust gas passage. An exhaust gas purification device selectively uses: a first NOx purification method in which hydrocarbon is sprayed from the hydrocarbon supply valve at predetermined intervals, purifying NOx contained in exhaust gas; and a second NOx purification method in which the air-fuel ratio of exhaust gas which flows into the exhaust gas purification catalyst is made rich at intervals longer than the predetermined intervals, causing the exhaust gas purification catalyst to release occluded NOx and cleaning the NOx. It is determined whether or not the exhaust gas purification catalyst is clogged with the deposition of particulates in the exhaust gas. When it is determined that the exhaust gas purification catalyst is clogged, the second NOx purification method is used. ## Claims ### Claim 1 An exhaust purification device for an internal combustion engine, comprising: an engine exhaust passage; an exhaust purification catalyst arranged inside the engine exhaust passage and having an exhaust gas flow surface, a precious metal catalyst being carried on the exhaust gas flow surface, a basic exhaust gas flow surface part being formed around the precious metal catalyst, the exhaust purification catalyst having a property of reducing NO x which is contained in the exhaust gas when making a concentration of hydrocarbons which flow into the exhaust purification catalyst vibrate with a vibration amplitude within a predetermined range of amplitude and with a vibration period within a predetermined range of period and having a property of being increased in amount of storage of NOx which is contained in the exhaust gas when making the vibration period of the hydrocarbon concentration longer than the predetermined range of period; a hydrocarbon feed valve arranged upstream of the exhaust purification catalyst in the engine exhaust passage; and an electronic control unit, wherein the electronic control unit is configured to selectively perform one of a first NOx removal method, and a second NOx removal method, wherein the electronic control unit is configured to control the hydrocarbon feed valve to inject hydrocarbon with a period within the predetermined range of period to thereby reduce NOx contained in the exhaust gas when the first NOx removal method is to be performed, wherein the electronic control unit is configured to control an air-fuel ratio of the exhaust gas which flows into the exhaust purification catalyst rich with a period longer than the predetermined range of period to thereby release stored NOx from the exhaust purification catalyst and reduce the NOx when the second NOx removal method is to be performed, wherein the electronic control unit is configured to judge whether the exhaust purification catalyst is clogged due to buildup of particulates in the exhaust gas, and wherein the electronic control unit is configured to perform the second NOx removal method when it is judged that the exhaust purification catalyst is clogged due to buildup of particulates in the exhaust gas. ### Claim 2 (depends on 1) The exhaust purification device for an internal combustion engine according to claim 1, wherein the exhaust purification device further comprises a temperature sensor which detects temperature of the exhaust purification catalyst, wherein the electronic control unit is configured to judge if the temperature of the exhaust purification catalyst is lower than a predetermined set temperature when it is judged that the exhaust purification catalyst is clogged due to buildup of particulates, and is configured to perform the second NOx removal method when it is judged that the temperature of the exhaust purification catalyst is lower than the predetermined set temperature. ### Claim 3 (depends on 2) The exhaust purification device for an internal combustion engine according to claim 2, wherein the electronic control unit is configured to increase the temperature of the exhaust purification catalyst to remove the particulate which deposited on the exhaust purification catalyst when it is judged that the temperature of the exhaust purification catalyst is higher than the predetermined set temperature. ### Claim 4 (depends on 1) The exhaust purification device for an internal combustion engine according to claim 1, wherein the exhaust purification device further comprises a pressure sensor which detects a pressure upstream of the exhaust purification catalyst in the exhaust passage and a differential pressure sensor which detects a pressure difference across a particulate filter which is arranged downstream of the exhaust purification catalyst in the exhaust passage, and wherein the electronic control unit is configured to judge if the exhaust purification catalyst is clogged due to buildup of particulates in the exhaust gas based on the pressure upstream of the exhaust purification catalyst in the exhaust passage and the differential pressure across the particulate filter. ### Claim 5 (depends on 1) The exhaust purification device for an internal combustion engine according to claim 1, wherein the exhaust purification device further comprises an air-fuel ratio sensor arranged downstream of the exhaust purification catalyst in the exhaust passage, wherein the electronic control unit is configured to change air-fuel ratio of the exhaust gas which flows into the exhaust purification catalyst instantaneously, and judge if the exhaust purification catalyst is clogged due to buildup of particulates based on an output of the air-fuel ratio at that time.