Electrical indirect petrol injection system for Otto cycle engines

摘要

There is disclosed an electronic indirect petrol injection system for Otto cycle engines, which comprises at least one air intake duct, one electroinjector for each engine cylinder, a feed circuit to feed the petrol to the electroinjectors under pressure, and an electronic assembly for controlling the injection timing during the cylinder intake stage and the duration of injection. The system also comprises a throttle valve located in the engine intake duct, a measuring element for the air flow rate disposed upstream of the throttle valve and a petrol, gas or gasoline pressure modulator arranged in the petrol feed circuit for the electroinjectors. Moreover, the electronic assembly comprises a tachometric unit which provides a signal which is a function of the engine rotation speed, a base electronic unit which processes electrical signals supplied by the tachometric unit and by the measuring element, a refining unit which modifies the time signal originating from the base unit according to the tachometric signal so as to optimize the engine operation at all points throughout its range of use, and a unit arranged to distribute electrical signals for opening the electroinjectors and keeping them open by a suitable timing arrangement.