Managing fuel volume change in fuel rail

摘要

A fuel volume accumulator is provided to hold rail pressure for hot engine restart and then reduce fuel pressure when the engine is off thereby minimizing evaporative emissions during diurnal cycles by preventing pressure build up as a temperature of a fuel system rises. The fuel volume accumulator comprises a fuel inlet body, and a moving element adapted to communicate with an inner surface of the fuel inlet body to define a fuel chamber. The fuel chamber is adapted to expand with substantially minimal pressure resistance until the extent of its volume is encountered. The fuel inlet body is in open communication at a first end with a fuel pump via a check valve and a fuel rail via an orifice which restricts fuel flow to substantially maintain a quick fuel rail re-pressurization.