System for controlling fuel injection for multiple-displacement engines

• US 4,541,387 A
• Filed: 05/13/1983
• Issued: 09/17/1985
• Est. Priority Date: 05/18/1982
• Status: Expired due to Fees

• Current Assignee: Fuji Jukogyo KK (Subaru Corp.)
• Original Assignee: Fuji Jukogyo KK (Subaru Corp.)
• Inventors: Morikawa, Koji
• Primary Examiner(s): Lazarus, Ira S.
• Application Number:
  US06/494,205
• Time in Patent Office: 858 Days
• Field of Search: 123/481, 123/198 F
• US Class Current: 123/481
• CPC Class Codes: F02B 1/04 with fuel-air mixture admission into cylinder
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123

Abstract

A system for controlling fuel injection for a multiple-displacement engine in which the number of operating cylinder changes according to the load on the engine by cutting off fuel to some of cylinders. The engine has solenoid-operated fuel injection valves and a switch is provided for rendering each solenoid-operated fuel injection valve inoperative. A sensor is provided for detecting load on the engine and for producing an output dependent on the load. A fuel injection control circuit is responsive to the output of the sensor for operating the switches to cut off the fuel to the corresponding cylinder. The fuel injection control circuit is so arranged to cut off the fuel to cylinders in accordance with idle cylinder patterns which are such that particular cylinders are not repeatedly idled and such that the number of idling cylinders by the fuel cut-off decreases with an increase of the load on the engine.

Claims

1. A system for controlling fuel injection for a multiple-displacement engine having cylinders and a respective solenoid-operated fuel injection valve for each cylinder, a throttle plate in an intake manifold communicating with the cylinders, a depressable accelerator pedal operatively connected to the throttle plate, and an electronic control unit, comprising:

switch means for rendering each solenoid-operated fuel injection valve respectively inoperative;

said accelerator pedal being arranged to be further depressed after a full throttle plate open position;

a throttle plate position sensor for producing an output signal in proportion to the throttle plate position;

an accelerator pedal position sensor for producing an output signal dependent on the accelerator pedal position;

a fuel injection control circuit responsive to said output signals of said throttle plate position sensor and said accelerator pedal position sensor for operating said switch means to cut off fuel to a corresponding of said cylinders, respectively;

said fuel injection control circuit being arranged to cut off the fuel to respective of said cylinders via corresponding of said switch means in accordance with idle cylinder patterns which are such that particular cylinders are not repeatedly idled, and such that the number of idling cylinders by the fuel cut-off is dependent on said output signals and progressively decreases with an increase of the depression degree of the accelerator pedal after the full throttle plate open position.

2. The system according to claim 1, wherein

said fuel injection control circuit is such that the number of idling cylinders is constant whenever the throttle plate is other than in the full throttle plate open position.