Fuel control system

• US 4,655,187 A
• Filed: 10/01/1985
• Issued: 04/07/1987
• Est. Priority Date: 10/13/1984
• Status: Expired due to Term

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Original Assignee: Lucas Industries Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Gravestock, Robert E.
• Primary Examiner(s): Argenbright, Tony M.
• Application Number:
  US06/782,489
• Time in Patent Office: 553 Days
• Field of Search: 123/481, 123/198 F
• US Class Current: 123/481
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/123 the fuel injection being cut-off
• CPC Class Codes: F02D 41/3818 for petrol engines
• CPC Class Codes: F02D 41/3827 for diesel engines
• CPC Class Codes: F02M 63/02 Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively

Abstract

A fuel control system for the fuel supply system of a compression ignition engine is arranged so that above a predetermined engine speed and below a predetermined level of fuel supply, fuel supply to the combustion chambers of the engine in turn is prevented. The remaining combustion chambers are arranged to receive an increased fuel supply to maintain the engine power.

Claims

1. A fuel control system for a fuel supply system for a multi-cylinder internal combustion engine of the compression-ignition type, the fuel supply system including at least one electromagnetically operated valve which is operated to cause fuel to be supplied to the combustion chambers of the associated engine, the fuel control system comprising first means responsive to engine position signals and to a fuel demand signal for providing a sequence of control signals for said valve, second means including an AND gate for driving said valve, one input of said AND gate receiving said sequence of control signals, an OR gate having its output connected to the other input of said AND gate, fuel demand comparison means and speed comparison means for comparing the actual fuel demand and the actual speed with fuel demand and speed reference signals, respectively, a further AND gate responsive to said fuel demand and speed comparison means and producing an output when the speed is above a predetermined value, switch means responsive to the output of said further AND gate and through which the fuel demand signal is supplied to said first means when the speed is below said predetermined value and the fuel demand is above said predetermined value and for supplying an extended fuel demand signal when the speed is above said predetermined value and the fuel demand is below said predetermined value, fuel demand modifying means for producing said extended fuel demand signal in response to a status signal, a sequence selection circuit responsive to the fuel demand signal for producing said status signal, the value of said status signal determining the extended fuel demand signal, circuit means responsive to said status signal and said engine position signals for supplying a series of sequence signals which coincide with said control signals, to one input of said OR gate, the other input of said OR gate being connected to receive the inverted output of said further AND gate, said series of sequence signals having every n^th one signal omitted to prevent operation of the valve, n being an odd number in the case of an engine having an even number of cylinders and the value of n depending on said status signal whereby, when the engine speed is above said predetermined value and the fuel demand is below the predetermined value, the firing of every n^th cylinder of the engine will be prevented.

2. A fuel control system according to claim 1, in which said circuit means comprises a plurality of shift registers corresponding to the values of the status signal produced by the sequence selection circuit, each shift register having a mask corresponding to a predetermined engine cylinder operating sequence.

3. A fuel control system according to claim 1 in which said second means includes an electronic distributor which distributes control signals to a plurality of said valves in turn.

4. A fuel control system according to claim 2 in which said second means includes an electronic distributor which distributes control signals to a plurality of said valves in turn.