초록 ▼

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 sys

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 including a rate shaping transfer passage 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 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, 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 is positioned in the rate shaping transfer passage to dampen reflected pressure waves thereby minimizing the adverse effects thereof.

대표청구항 ▼

A fuel system for supplying fuel at a predetermined pressure through plural fuel injection lines to the corresponding cylinders of a multi-cylinder internal combustion engine, comprising: a fuel supply means for supplying fuel for delivery to the internal combustion engine, said fuel supply means in

A fuel system for supplying fuel at a predetermined pressure through plural fuel injection lines to the corresponding cylinders of a multi-cylinder internal combustion engine, comprising: a fuel supply means for supplying fuel for delivery to the internal combustion engine, said fuel supply means including a fuel transfer circuit; a pump means for pressurizing fuel above the predetermined pressure; an accumulator means for accumulating and temporarily storing fuel at high pressure received from said pump means; a fuel distributor means fluidically connected with said accumulator means through said fuel transfer circuit for enabling sequential periodic fluidic communication with the engine cylinders through the corresponding fuel injection lines; a solenoid operated injection control valve positioned within said fuel transfer circuit between said accumulator means and said fuel distributor means for controlling the fuel injected into each engine cylinder during each of the sequential periods of communication enabled by said fuel distributor means to thereby define sequential injection events, said solenoid operated injection control valve movable between an open position permitting fuel flow from said accumulator means to said fuel distributor means and a closed position blocking fuel flow from said accumulator means to said fuel distributor means; and a rate shaping control means positioned within said fuel transfer circuit between said accumulator means and said fuel distributor means for producing a predetermined time varying change in the pressure of fuel occurring sequentially at each engine cylinder to effect injection, wherein fuel from said accumulator means is capable of reaching a maximum unrestricted flow rate corresponding to a maximum pressure in each of said fuel injection lines adjacent the respective engine cylinder during said injection event, said rate shaping control means including a rate shaping transfer passage positioned between said accumulator means and said injection control valve, said rate shaping transfer passage having a predetermined length and a predetermined cross sectional flow area sufficient to cause a predetermined time delay between the movement of said solenoid operated injection control valve to the open position and the attainment of said maximum pressure, wherein said predetermined cross sectional flow area of said rate shaping transfer passage is selected to cause said maximum pressure to reach a predetermined level.