Pulsed air assist air valve module

摘要

A fuel injector for use in a internal combustion engine is disclosed. The fuel injector includes a body having a discharge end and a longitudinal axis extending therethrough, and an electromagnetic coil located within the body. The fuel injector further includes a fuel metering valve operable between an open position and a closed position and an air metering valve operable between an open position and a closed position. The fuel injector also includes a valve seat located within the body proximate to the discharge end and includes an orifice extending therethrough along the longitudinal axis. A needle is reciprocally mounted along the longitudinal axis between an open position and a closed position. The needle has an upstream end, a downstream end, and a needle channel extending therethrough along the longitudinal axis. The needle engages the valve seat in the closed position. A guide is disposed along the longitudinal axis such that the upstream end of the needle is reciprocable within the guide. A seal having a seal opening therethrough is located within the guide. A bellows fluidly connects the seal opening and the needle channel. The bellows and the guide form a generally annular chamber therebetween. The bellows is movable between a compressed and an extended position. The annular chamber is adapted to receive fuel. The seal prevents the fuel in the annular chamber from entering the needle channel. A method of operating the fuel injector is also disclosed.