EXHAUST GAS CLEANING DEVICE FOR INTERNAL COMBUSTION ENGINES Russian patent published in 2017 - IPC F01N3/08 F01N9/00 

FIELD: engine devices and pumps.

SUBSTANCE: device includes an additive supply valve (230) that injects an aqueous urea solution onto a diffusion plate (60) located in the exhaust passage (26). The valve (260) is connected to the urea aqueous solution supply pipe (240). The device also comprises a catalyst (41) and a controller (80). The catalyst (41) removes NOx from the exhaust gas using ammonia as the reducing agent, and the controller (80) is configured to set the injection timing of the aqueous urea solution according to a predetermined cycle. The controller (80) further includes units of calculating temperature, memory, producing the first injection pressure, calculating the second injection pressure, and calculating the third injection pressure. The temperature unit is configured to calculate the temperature of the plate (60), the memory unit is configured to store information on the urea solution injection pressure, the pressure producing unit is configured to obtain the first injection pressure during the previous injection of the urea solution from the memory unit. The second injection pressure corresponds to the injection pressure obtained when the urea solution is injected at the first time corresponding to the injection cycle elapsed after the previous injection. The third injection pressure is the injection pressure at the second time moment. The controller (80) is also configured to increase the pressure drop when the temperature of the diffusion plate is less than a predetermined temperature threshold. The first pressure drop, which is the absolute value of the difference between the first injection pressure and the second injection pressure, is less than the differential pressure drop threshold. And urea injection at the second time moment will cause the second pressure drop that is the absolute value of the difference between the third injection pressure and the first injection pressure, and which is larger than the first pressure drop. During the differential pressure increase process, the controller (80) sets, as the urea injection point, the second time point at which the second pressure drop exceeds the first pressure drop.

EFFECT: increase in the pressure drop of the urea injection in order to prevent the continuous pressure of the urea jet at the same point of the plate.

13 cl, 13 dwg