FUEL INJECTION RATE SHAPING CONTROL SYSTEM

摘要

A fuel injection rate shaping control system is provided which effectively controls the flow rate of fuel injected into the combustion chamber of an engine to improve combustion and reduce emissions by controlling the rate of pressure increase during injection. The injection rate shaping control system includes a rate shaping control device (10) including a rate shaping transfer passage (22) having a predetermined length and diameter specifically designed to create a desired injection pressure rate shape. In other embodiments of the present invention, two or more rate shaping transfer passages (72, 74) capable of producing distinct rate shapes are packaged in various fuel injection systems to selectively provide various rate shapes depending on operating conditions. Switching valves, i.e. solenoid operated three-way valves (76, 84, 86), may be used to direct the fuel or timing fluid flow to any one of the rate shaping transfer passages. Also, a dampening means in the form of a reverse flow restrictor valve (26) is positioned in the rate shaping transfer passage to dampen reflected pressure waves thereby minimizing the adverse effects thereof.