Patent ID: 9587547
Date: 2017-03-07
CPC Classifications: F01N,F02M,Y02T

Claim:
1. An engine system for controlling an exhaust gas flow, comprising: an intake line arranged to draw in outdoor air; an engine for combusting the outdoor air supplied through the intake line and fuel in a combustion chamber of the engine to generate torque; an exhaust line for exhausting exhaust gas from the combustion in the combustion chamber of the engine; a turbocharger having a turbine operated by the exhaust gas passing through the exhaust line and a compressor for compressing the outdoor air in the intake line; a catalyst unit arranged on a downstream side of the turbocharger for reducing harmful components of the exhaust gas; a bypass line branched from the exhaust line on the downstream side of the turbocharger and joined to the exhaust line on a downstream side of the catalyst unit; a bypass valve arranged on the bypass line for selectively opening/closing the bypass line; and a control unit for selectively opening/closing the bypass valve; wherein if a condition is met in which the fuel is not injected into the engine and a rotation speed of the engine is higher than a preset speed, the control unit opens the bypass valve so that the exhaust gas bypasses the turbocharger and the catalyst unit, and if the condition is not met, the control unit closes the bypass valve, and wherein the control unit controls the bypass valve based on an analysis of an accelerator pedal signal, a coolant temperature of the engine, a vehicle speed, and a signal of a lambda sensor arranged between the turbocharger and the engine.