Patent ID: 9605574
Date: 2017-03-28
CPC Classifications: F01N,G01K,G01N,Y02A,Y02T

Claim:
1. A urea water pipe clogging detection device for urea selective catalytic reduction configured to suck urea water from a urea water tank with a supply pump and spray the urea water from a dosing valve disposed upstream of an selective catalytic reduction device via a pressurized urea water feed line, and detect clogging of a pipe segment that extends to the dosing valve from the supply pump, said urea water pipe clogging detection device comprising: a urea water sensor configured to detect urea water temperature in the urea water tank; a pressure sensor configured to detect pressure of the pressurized urea water feed line; an exhaust gas temperature sensor disposed on an exhaust pipe upstream of the selective catalytic reduction device; and a clogging determination unit configured to perform startup control for driving the supply pump and increasing pressure in the pipe segment upon turning on of a key switch, and then perform emptying control for returning the urea water from the pipe segment to the urea water tank if a detection value of the exhaust gas temperature sensor is less than or equal to a predetermined temperature and a detection value of the urea water sensor is greater than or equal to a freezing temperature, the clogging determination unit being configured to detect the clogging of the pipe segment from the detection value of the pressure sensor during the emptying control.