System for aiding regeneration of catalyst fitted in vehicle engine exhaust by multiple fuel injections during cylinder expansion phase

摘要

The engine (1) has a control system (17) designed to start regenerating a catalyst (6) by initiating a phase of multiple fuel injections into the cylinders during expansion The engine is connected to various items including an air inlet (2), a fuel feed system (8) using electronically controlled injectors (9, 10, 11, 12) into the cylinders, a data acquisition system (20, 21, 22, 23, 24) and a control system (17) operating the air inlet and/or fuel feed to control the operation of the engine. Preferred Features: The engine is a diesel engine. The catalyst is upstream of a particle filter in the exhaust pipe. The quantities of fuel injected are 5-50 mm3 per injection, per cylinder and per liter of cylinder volume. The catalyst is an oxidation catalyst, or a de-nitrogen oxide catalyst of a NOx trap. The fuel feed system is a high pressure common gradient system or has pump-injectors.