Fuel injection system and method for a diesel or stratified charge engine

• US 5,313,924 A
• Filed: 03/08/1993
• Issued: 05/24/1994
• Est. Priority Date: 03/08/1993
• Status: Expired due to Term

• Current Assignee: Chrysler Group LLC (Stellantis NV)
• Original Assignee: Chrysler Corporation (Stellantis NV)
• Inventors: Regueiro, Jose F.
• Primary Examiner(s): Cross, E. Rollins
• Assistant Examiner(s): Moulis, Thomas N.
• Application Number:
  US08/028,891
• Time in Patent Office: 442 Days
• Field of Search: 123/506, 123/458, 123/456, 123/447, 123/467, 123/357
• US Class Current: 123/456
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: F02D 2041/389 for injecting directly into the cylinder
• CPC Class Codes: F02D 2200/0602 Fuel pressure
• CPC Class Codes: F02D 2250/31 Control of the fuel pressure
• CPC Class Codes: F02D 41/3836 Controlling the fuel pressure
• CPC Class Codes: F02D 41/3863 by controlling the flow out of the common rail, e.g. using pressure relief valves
• CPC Class Codes: F02M 55/025 Common rails
• CPC Class Codes: F02M 59/102 Mechanical drive, e.g. tappets or cams F02M45/063 takes precedence
• CPC Class Codes: F02M 63/0225 Fuel-injection apparatus having a common rail feeding several injectors F02M63/0003 takes precedence; Means for varying pressure in common rails; Pumps feeding common rails

Abstract

A fuel injection system and method is disclosed which includes a high pressure pump that supplies fuel to a high pressure common rail, a plurality of electronically controlled fuel injectors that supply fuel from the common rail directly into different ones of the engine cylinders, a pressure regulator that varies the pressure of fuel contained in the common rail, a load sensor, an engine speed sensor, a crankshaft position sensor, and an electronic control unit coupled to control the pressure regulator and fuel injectors in response to signals received from the load sensor, speed sensor, and crankshaft position sensors. Using the pressure regulator and fuel injectors, the electronic control unit can provide independent control of the quantity of fuel injected into the cylinders, as well as the timing and duration of injection. The electronic control unit can be programmed to accommodate various engine environmental and state conditions for optimal engine performance. The high pressure pump can comprise the pumping element(s) from a rotary pump or a modified in-line or jerk-type pump having means for providing coarse control of the pressure in the common rail.

Claims

1. An electrically controlled high pressure fuel injector system for an internal combustion engine having plural cylinders and a crankshaft, comprising:

a low pressure fuel supply line connected to a supply of fuel;

a high pressure pump connectable to said low pressure fuel supply line and said supply of fuel;

a high pressure common rail coupled to said high pressure pump to receive pressurized fuel from said high pressure pump and the fuel supply;

a plurality of electrically controlled fuel injectors, each coupled to said common rail and responsive to an injector signal to selectively supply fuel from said common rail directly into one of the cylinders;

a first pressure regulator coupled to said common rail, said pressure regulator being responsive to a pressure control signal to vary the fuel pressure in said common rail;

a pressure sensor coupled to said common rail to generate a pressure signal indicative of the measured pressure of fuel in said common rail;

a load sensor which generates a load signal indicative of the position of a control mechanism that controls the engine output;

a speed sensor which generates a speed signal indicative of engine speed;

a shaft position sensor which generates a shaft position signal indicative of the angular position of the crankshaft;

a sequencing sensor which generates a sequence signal that is indicates which of said fuel injectors is to receive the next injection signal;

an electronic control unit coupled to control said pressure regulator and each of said fuel injectors, said electronic control unit being responsive to said load sensor, speed sensor, shaft position sensor, and sequencing sensor to generate the injection signals and being responsive to said load sensor, speed sensor, and pressure sensor to generate the pressure control signal;

a second pressure regulator attached to said low pressure fuel supply line and coupled to said electronic control unit, said second pressure regulator being responsive to a low pressure control signal generated by said electronic control unit to vary the pressure of fuel in said low pressure fuel supply line; and

a second pressure sensor coupled to said low pressure fuel supply line to supply a low pressure signal to said electronic control unit indicative of the measured pressure of fuel in said low pressure fuel supply line, said electronic control unit being responsive to the low pressure signal to generate the low pressure control signal.