Engine Management Systems - Denso-am.eu

Engine Management SystemsEGR ValvesGBHow they workTypesThe achievement of cleaner vehicle exhaust gas owes much to thequality and efficiency of the Exhaust Gas Recirculation (EGR) Valve.The role of the EGR Valve is to mix the engine’s exhaust gas withthe intake air as appropriate for the driving conditions, reducing theconcentration of oxygen in the intake air and slowing the combustionspeed. As the result of reduced oxygen density during air intake,combustion temperature decreases and lower levels of harmfulnitrogen oxide (NOx) are generated.> A small passageway exists between the intake and exhaustmanifolds. This is where the Exhaust Gas Recirculation (EGR)Valve is located, where it adjusts the amount of recirculatedexhaust gas back into the intake manifold> When the engine is idling, the EGR Valve is closed and there isno EGR flow into the intake manifold. The EGR Valve remainsclosed until the engine is warm and operating under load. As theload and combustion temperature start to increase, the EGR Valveis opened and begins to send exhaust gas back into the intakemanifold> Step motor type> Solenoid type> DC motor typeFeatures and benefits> Responsiveness: Optimal exhaust gas flow adaptation for allengine temperatures and driving conditions> Precision: Integrated position sensor allows more accurate controlof exhaust gases, resulting in a higher level of precision> Durability: Reduction in the effect of exhaust pressure andexhaust flow provides carbon corrosion resistance and longer life> Emission reducing: Reduced NOx emissionsExhaust Gas Recirculation(EGR) Valve> Due to the technological advances achieved in EGR control andcatalyst technology, cleaner exhaust has been achieved evenunder lean-burn conditionsEGR PipeEGR Valve Mounting LocationCharacteristics> Coils: Activate magnetic rotor when the current flows to the coils, due to the signals fromECU> Magnetic rotor: Turns and energises valve shaft forwards and backwards, adjusting theclearance between the valve and valve seat> Valve spring: Forcing valve to close at non-magnetised duration> Bush: Stabilises the valve screw, which changes rotary motion into linear motion> Inner / Outer Sleeve: ‘Maze’ sleeve construction prevents harmful materials coming intobush> Valve: Poppet valve structure cancel the force applied to the valve8