Injector for injecting a gaseous reducing agent into an exhaust gas stream, comprising at least one anti-backflow device

An exhaust line for an internal combustion engine comprising:

• a mixer configured to be crossed by an exhaust gas stream produced by the internal combustion engine;
• an injector to inject a reducing agent into said exhaust gas stream, the injector comprising at least one injection nozzle;
• a dosing system to provide a dosed flow of the reducing agent to the or each injection nozzle;
• and
• an injection line fluidically connecting the dosing system to the at least one or each injection nozzle, wherein the injection line comprises an upstream pipe fluidically connected to the dosing system, at least one downstream pipe fluidically connected to a respective injection nozzle, and at least one anti-backflow device to avoid or minimize fluidic flow from the at least one or each downstream pipe toward the upstream pipe, and wherein the at least one anti-backflow device has at least one constriction that comprises a reduced flow-section relative to the at least one downstream pipe, and/or comprises at least one chicane that is located internally within the injection line, and wherein a ratio between a flow section of the at least one downstream pipe and a flow section of the at least one constriction is comprised between 4 and 25.

An automotive vehicle comprising:

• an exhaust line for an internal combustion engine comprising a mixer configured to be crossed by an exhaust gas stream produced by the internal combustion engine;
• an injector to inject a reducing agent into said exhaust gas stream, the injector comprising at least one injection nozzle;
• a dosing system to provide a dosed flow of the reducing agent to the at least one or each injection nozzle;
• and
• an injection line fluidically connecting the dosing system to the at least one or each injection nozzle, wherein the injection line comprises an upstream pipe fluidically connected to the dosing system, at least one downstream pipe fluidically connected to a respective injection nozzle, and at least one anti-backflow device to avoid or minimize fluidic flow from the at least one or each downstream pipe toward the upstream pipe, and wherein the at least one anti-backflow device has at least one constriction that comprises a reduced flow-section relative to the at least one downstream pipe, and/or comprises at least one chicane that is located internally within the injection line, and wherein a ratio between a flow section of the at least one downstream pipe and a flow section of the at least one constriction is comprised between 4 and 25.