# US 10,865,677 B2 · Exhaust gas purification device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,865,677 B2 - Document ID: US10865677B2 - Status: Granted - Kind: B2 - Application number: 15/559,034 - Filed: 2016-03-14 - Published: 2018-03-22 - Granted: 2020-12-15 - Earliest claimed: 2015-03-18 - Assignees: Yanmar Power Technology Co., Ltd. - Applicants: Yanmar Co., Ltd. - Inventors: Yoshinori Fukui; Arata Hayata; Yoshihiro Yamaguchi; Tsuyoshi Inoue - Web page: https://patentgrep.com/patent/US10865677B2 ## CPC - F01N 3/05: by means of air, e.g. by mixing exhaust with air (silencers working by addition of air to exhaust F01N1/14; arrangements for the supply of additional air for the thermal or catalytic conversion of noxious components of exhaust F01N3/30) - B01D 53/94: by catalytic processes - F01N 3/023: using means for regenerating the filters, e.g. by burning trapped particles - F01N 3/08: for rendering innocuous (using electric or electrostatic separators F01N3/01; chemical aspects B01D53/92) - F01N 3/20: specially adapted for catalytic conversion (F01N3/22 takes precedence) - F01N 3/2066: {Selective catalytic reduction [SCR]} - F01N 3/22: Control of additional air supply only, e.g. using by-passes or variable air pump drives - F01N 3/28: Construction of catalytic reactors - B01D 53/9409: {Nitrogen oxides} - F01N 2590/02: for marine vessels or naval applications - 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) ## Abstract An embodiment of an exhaust gas purification device has a function of removing soot adhered to an NOx catalyst arranged inside a cylindrical casing part by injecting pressurized air. The device includes a plurality of air injection nozzles arranged on a side wall of the casing part on an upstream side of the NOx catalyst, which are each configured to generate an impulse wave by injecting pressurized air into the casing part, wherein the air injection nozzles successively inject one by one an equal flow quantity of pressurized air, for a period, at predetermined time intervals. ## Claims ### Claim 1 An exhaust gas purification device having a function of removing soot adhered to a plurality of catalysts arranged inside a casing by injecting pressurized air, comprising: a plurality of air injection nozzles arranged on a side wall of the casing, each air injection nozzle configured to generate an impulse wave within the casing by injecting the pressurized air into the casing, the plurality of air injection nozzles are positioned upstream of the plurality of catalysts with respect to a direction of a flow of exhaust gas through the casing, wherein: the plurality of air injection nozzles successively inject one by one the pressurized air, for a duration of t1, into the casing, with predetermined time intervals of a duration t2 between the successive injections; the duration of t1 is between 0.1 seconds and 0.5 seconds and the duration of t2 is between 30 seconds and 5 minutes; and the impulse wave applies a force on the plurality of catalysts which causes pressure fluctuations and causes the soot adhered to the plurality of catalysts to be removed. ### Claim 2 (depends on 1) The exhaust gas purification device according to claim 1, wherein the exhaust gas purification device is configured such that pressurized air is not injected from any of the plurality of air injection nozzles for a predetermined period after a last air injection nozzle of the plurality of air injection nozzles injects pressurized air. ### Claim 3 (depends on 1) The exhaust gas purification device according to claim 1, wherein: the casing comprises a quadrangular tube, and each air injection nozzle of the plurality of air injection nozzles is arranged on a single side wall of the quadrangular tube. ### Claim 4 (depends on 1) The exhaust gas purification device according to claim 1, wherein a flow quantity of pressurized air injected from one of the plurality of air injection nozzles varies depending on a number of the plurality of air injection nozzles. ### Claim 5 (depends on 1) The exhaust gas purification device according to claim 1, wherein a flow quantity of pressurized air injected from one of the plurality of air injection nozzles decreases with an increase in a number of the plurality of air injection nozzles. ### Claim 6 (depends on 1) The exhaust gas purification device according to claim 1, wherein the plurality of catalysts are arranged in the direction of the flow of the exhaust gas through the casing, wherein the plurality of air injection nozzles are arranged perpendicular to the direction of the flow of the exhaust gas through the casing. ### Claim 7 (depends on 6) The exhaust gas purification device according to claim 6, wherein the plurality of air injection nozzles are integrated on the side wall of the casing. ### Claim 8 (depends on 1) The exhaust gas purification device according to claim 1, wherein: the plurality of air injection nozzles comprise non-directional nozzles; the impulse wave generated from each of the plurality of air injection nozzles has no directivity; and the impulse wave spherically propagates inside the casing. ### Claim 9 (depends on 2) The exhaust gas purification device according to claim 2, wherein the plurality of air injection nozzles are arranged along the side wall of the casing at regular intervals in a direction of the casing that is perpendicular to the direction of the flow of the exhaust gas through the casing. ### Claim 10 (depends on 1) The exhaust gas purification device according to claim 1, further comprising an air supply passage configured to provide the pressured air to one or more air injection nozzles of the plurality of air injection nozzles. ### Claim 11 An exhaust system comprising: an exhaust gas purification device comprising: a casing; a plurality of catalysts arranged inside the casing; and a plurality of air injection nozzles arranged on a side wall of the casing, each air injection nozzle configured to generate an impulse wave within the casing by injecting pressurized air into the casing, the plurality of air injection nozzles are positioned upstream of the plurality of catalysts with respect to a direction of a flow of exhaust gas through the casing, wherein the impulse wave is configured to remove soot adhered to the plurality of catalysts upon impingement of the impulse wave on the plurality of catalysts; an air supply passage configured to provide the pressurized air to one or more each of the plurality of air injection nozzles; and a controller configured to cause the plurality of air injection nozzles to successively inject one by one the pressurized air for an air injection duration into the casing with predetermined time intervals between the successive injections. ### Claim 12 (depends on 11) The exhaust system according to claim 11, wherein the controller is configured to send activation signals to multiple valves of the air supply passage to cause the air injection duration of the plurality of air injection nozzles between 0.1 seconds and 0.5 seconds and to cause the predetermined time intervals between the successive injections to be between 30 seconds and 5 minutes. ### Claim 13 (depends on 11) The exhaust system according to claim 11, wherein: the casing comprises a composite casing that includes a partition and that defines two paths; and the partition separates the two paths. ### Claim 14 (depends on 11) The exhaust system according to claim 11, wherein: the casing comprises a quadrangular tube portion; the plurality of air injection nozzles are arranged in a width direction on a single side wall of the casing; and a direction of an injection port of the plurality of air injection nozzles is arranged perpendicular to the direction of the flow of the exhaust gas through the casing. ### Claim 15 (depends on 11) The exhaust system according to claim 11, wherein: the plurality of air injection nozzles comprise non-directional nozzles; and the impulse wave is configured to spherically propagate in the casing. ### Claim 16 A method of operating an exhaust gas purification device, the method comprising: injecting, by a first air injection nozzle of a plurality of air injection nozzles arranged on a side wall of a casing of the exhaust gas purification device and upstream of a plurality of catalysts of the exhaust gas purification device, first pressurized air into the casing for a first duration between 0.1 seconds and 0.5 seconds to generate a first impulse wave within the casing, the first impulse wave configured to remove soot adhered to the plurality of catalysts upon impingement of the first impulse wave on the plurality of catalysts; and after a time interval between 30 seconds and 5 minutes, injecting, by a second air injection nozzle of the plurality of air injection nozzles, second pressurized air into the casing for a second duration between 0.1 seconds and 0.5 seconds to generate a second impulse wave within the casing, the second impulse wave configured to remove soot adhered to the plurality of catalysts upon impingement of the second impulse wave on the plurality of catalysts. ### Claim 17 (depends on 16) The method according to claim 16, further comprising, after a period of longer than 20 minutes from an end of a final injection of a last air injection nozzle of the plurality of air injection nozzles, injecting, by the first air injection nozzle, third pressurized air into the casing for a third duration between 0.1 seconds and 0.5 seconds to generate a third impulse wave within the casing. ### Claim 18 (depends on 16) The method according to claim 16, further comprising, after a second time interval between 30 seconds and 5 minutes, injecting, by the second air injection nozzle of the plurality of air injection nozzles, fourth pressurized air into the casing for a fourth duration between 0.1 seconds and 0.5 seconds to generate a fourth impulse wave within the casing. ### Claim 19 (depends on 16) The method according to claim 16, wherein: the casing comprises a quadrangular tube portion; the plurality of air injection nozzles are arranged in a width direction on a single side wall of the casing; and a direction of an injection port of the plurality of air injection nozzles is arranged perpendicular to a direction of a flow of exhaust gas through the casing.