# US 11,441,457 B2 · Two-stroke engine exhaust resonator with exhaust gas catalytic converter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,441,457 B2 - Document ID: US11441457B2 - Status: Granted - Kind: B2 - Application number: 16/970,576 - Filed: 2019-02-19 - Published: 2021-04-22 - Granted: 2022-09-13 - Earliest claimed: 2018-02-19 - Applicants: Martin Sula - Inventors: Martin Sula - Web page: https://patentgrep.com/patent/US11441457B2 ## CPC - F01N 1/026: {Annular resonance chambers arranged concentrically to an exhaust passage and communicating with it, e.g. via at least one opening in the exhaust passage} - F01N 1/084: {the exhaust gases flowing through the silencer two or more times longitudinally in opposite directions, e.g. using parallel or concentric tubes} - F01N 1/089: {using two or more expansion chambers in series (F01N1/083, F01N1/084, F01N1/086 take precedence)} - F01N 3/04: using liquids - F01N 3/10: by thermal or catalytic conversion of noxious components of exhaust - F01N 3/2046: {Periodically cooling catalytic reactors} - F01N 3/2885: {with exhaust silencers in a single housing} - F01N 13/141: {Double-walled exhaust pipes or housings} - G10K 11/172: using resonance effects - F01N 2230/04: Catalytic converters - F01N 2240/02: a heat exchanger - F01N 2260/024: using a liquid - F01N 2260/08: for preventing heat loss or temperature drop, using other means than layers of heat-insulating material - F01N 2260/20: for heat or sound protection, e.g. using a shield or specially shaped outer surface of exhaust device - F01N 2470/20: Dimensional characteristics of tubes, e.g. length, diameter - F01N 2470/24: Concentric tubes or tubes being concentric to housing, e.g. telescopically assembled - F01N 2470/30: Tubes with restrictions, i.e. venturi or the like, e.g. for sucking air or measuring mass flow - F01N 2490/18: Dimensional characteristics of gas chambers - F01N 2590/00: Exhaust or silencing apparatus adapted to particular use, e.g. for military applications, airplanes, submarines - Y02T 10/12: Improving ICE efficiencies - 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) - G10K: SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A two-stroke engine exhaust resonator with an exhaust gas catalytic converter comprising an inlet opening, wherein the inlet opening is followed by the first end of a stabilizing tube with a catalytic converter mounted thereon, characterized in that the other end of the stabilizing tube is directed towards the primary reflective surface, the primary reflective surface is followed by the first end of a resonator casing, which is surrounding the stabilizing tube, wherein the resonator casing exceeds at least over a part of the catalytic converter on the stabilizing tube, wherein a resonator outlet opening is arranged in the resonator casing between its first and second end or in the primary reflective surface, and at least a part of the resonator casing surrounding the stabilizing tube is surrounded by a cooler. ## Claims ### Claim 1 A two-stroke engine exhaust resonator comprising: a resonator casing, an inlet opening (1) of the resonator casing directly connected to a first end of a stabilizing tube (2) with a catalytic converter (8) mounted thereon, a second end of the stabilizing tube (2) directed towards a primary reflective surface (3) connected to a first end of the resonator casing which is surrounding the stabilizing tube (2) and thus defining a space in a resonant chamber between the resonator casing and the stabilizing tube (2), and said space comprising a narrowing part defined by a body of the catalytic converter (8) and the resonator casing, wherein said narrowing part enables compression of combustion gases between the stabilizing tube (2) and the resonator casing following prior expansion of combustion gases coming out from the catalytic converter (8) inside the stabilizing tube (2), and further reflection at the primary reflective surface (3) outside the stabilizing tube (2), wherein the resonator casing extends over at least a part of the catalytic converter (8) on the stabilizing tube (2), wherein a resonator outlet opening (7) is arranged in the resonator casing between the first end of the resonator casing and a second end of the resonator casing or in the primary reflective surface (3) of the resonator casing, and at least a part of the resonator casing surrounding the stabilizing tube (2) is surrounded by a cooler (10). ### Claim 2 (depends on 1) The two-stroke engine exhaust resonator according to claim 1, wherein the cooler (10) is provided with a coolant outlet (13) directed from the cooler (10) through the resonator casing into the resonant chamber for injecting coolant into the combustion gas flow in the resonant chamber. ### Claim 3 (depends on 1) The two-stroke engine exhaust resonator according to claim 1, wherein the catalytic converter (8) is mounted on the stabilizing tube (2) in an initial part. ### Claim 4 (depends on 1) The two-stroke engine exhaust resonator according to claim 1, wherein the cooler (10) surrounds at least a part of the primary reflective surface (3). ### Claim 5 (depends on 4) The two-stroke engine exhaust resonator according to claim 4, wherein the resonator casing exceeds over the whole catalytic converter (8) on the stabilizing tube (2). ### Claim 6 (depends on 1) The two-stroke engine exhaust resonator according to claim 1, wherein the outlet opening (7) of the resonator exits the primary reflective surface (3) in an axis of the resonator. ### Claim 7 (depends on 6) The two-stroke engine exhaust resonator according to claim 6, wherein the catalytic converter (8) is mounted on the stabilizing tube (2) in an initial part. ### Claim 8 (depends on 1) The two-stroke engine exhaust resonator according to claim 1, wherein the resonator casing exceeds over the whole catalytic converter (8) on the stabilizing tube (2). ### Claim 9 (depends on 8) The two-stroke engine exhaust resonator according to claim 8, wherein the outlet opening (7) of the resonator exits the primary reflective surface (3) in an axis of the resonator. ### Claim 10 (depends on 8) The two-stroke engine exhaust resonator according to claim 8, wherein the catalytic converter (8) is mounted on the stabilizing tube (2) in an initial part. ### Claim 11 (depends on 1) The two-stroke engine exhaust resonator according to claim 1, wherein the resonator casing is formed by a resonator primary casing (4) and a resonator secondary casing (6), the resonator primary casing (4) connects, with a first end, to the primary reflective surface (3), surrounds the stabilizing tube (2) of the resonator casing, exceeds at least a part of the catalytic converter (8) on the stabilizing tube (2) and is directed towards a secondary reflective surface (5) which is connected to a first end of the resonator secondary casing (6) surrounding at least a part of the resonator primary casing (4) exceeding at least a part of the catalytic converter (8) on the stabilizing tube (2) and terminating with a second end of the resonator secondary casing (6). ### Claim 12 (depends on 11) The two-stroke engine exhaust resonator according to claim 11, wherein the resonator casing exceeds over the whole catalytic converter (8) on the stabilizing tube (2). ### Claim 13 (depends on 12) The two-stroke engine exhaust resonator according to claim 12, wherein the cooler (10) surrounds at least a part of the primary reflective surface (3). ### Claim 14 (depends on 13) The two-stroke engine exhaust resonator according to claim 13, wherein the cooler (10) is provided with a coolant outlet (13) directed from the cooler (10) through the resonator casing into the resonant chamber for injecting coolant into the combustion gas flow in the resonant chamber. ### Claim 15 (depends on 14) The two-stroke engine exhaust resonator according to claim 14, wherein the catalytic converter (8) is mounted on the stabilizing tube (2) in an initial part. ### Claim 16 (depends on 14) The two-stroke engine exhaust resonator according to claim 14, wherein the outlet opening (7) of the resonator exits the primary reflective surface (3) in an axis of the resonator. ### Claim 17 (depends on 16) The two-stroke engine exhaust resonator according to claim 16, wherein the catalytic converter (8) is mounted on the stabilizing tube (2) in an initial part.