High pressure pumpless fuel system.

摘要

A fuel delivery system for an internal combustion engine has a fuel tank (10) with a piston (16) movably mounted on a guide rod (18) therein to separate the tank (10) into two variable volumes, one for containing fuel and the other for containing pressurised air to act on the piston (16) for compressibly pressurising the fuel, thus preventing fuel vaporisation during normal fuel delivery. Pressurised air is provided to the pressure volume by an air regulator (80) or a positive displacement pump, either of which can be controlled by a microprocessor based electronic engine control unit. A filler pipe attached to the tank (10) has at least one anti-expulsion valve (60) therein and pressure interlock means for preventing fuel expulsion through the filler (12) pipe when the tank (10) is pressurised. A pressure accumulator (62) is connected to the fuel line (22) to assist in providing a constant fuel pressure to the engine. <IMAGE>