DRAINAGE SYSTEM OF INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a drainage system of an internal combustion engine capable of preventing torque reduction and output reduction by properly controlling an opening/closing motion of an opening/closing valve disposed on the way of a drainage channel.SOLUTION: A drainage system of an internal combustion engine includes: an intake passage IR connected to an intake side of an internal combustion engine 1 at one end; an exhaust passage ER connected to an exhaust side of the internal combustion engine 1 at one end; an intercooler 10 disposed in the intake passage IR; a catalyst 18 disposed in the exhaust passage ER; a drain passage wr connected to the intake passage IR at a downstream side of the intercooler at one end, connected to the exhaust passage ER at an upstream side of the catalyst 18 at the other end, and discharging condensate water condensed by the intercooler to the exhaust passage; an opening/closing valve 29 disposed on the way of the drain passage; an oxygen concentration sensor 20 disposed in the exhaust passage at a downstream side with respect to a connecting portion of the drain passage and the exhaust passage; and an opening/closing valve control portion 30 controlling opening and closing of the opening/closing valve 29 on the basis of the oxygen concentration output in an exhaust gas detected by the oxygen concentration sensor.