Internal combustion engine control for improved fuel efficiency

• US 9,086,024 B2
• Filed: 02/24/2014
• Issued: 07/21/2015
• Est. Priority Date: 07/11/2008
• Status: Expired due to Fees

• Current Assignee: Tula Technology, Incorporated (BorgWarner Incorporated)
• Original Assignee: Tula Technology, Incorporated (BorgWarner Incorporated)
• Inventors: Tripathi, Adya S., Silvestri, Chester J.
• Primary Examiner(s): Vo, Hieu T
• Application Number:
  US14/188,479
• Publication Number:
  US 20140172272A1
• Time in Patent Office: 512 Days
• US Class Current: 1/1
• CPC Class Codes: F02B 2075/027 four
• CPC Class Codes: F02B 75/02 Engines characterised by their cycles, e.g. six-stroke
• CPC Class Codes: F02D 13/06 Cutting-out cylinders
• CPC Class Codes: F02D 17/02 Cutting-out cutting-out engines in multiple engine arrangements F02D25/04
• CPC Class Codes: F02D 2200/0614 Actual fuel mass or fuel injection amount
• CPC Class Codes: F02D 2200/602 Pedal position
• CPC Class Codes: F02D 2250/18 Control of the engine output torque
• CPC Class Codes: F02D 2400/02 Four-stroke combustion engines with electronic control
• CPC Class Codes: F02D 37/02 one of the functions being ignition
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/1401 characterised by the control or regulation method F02D41/1473, F02D41/1477 take precedence
• CPC Class Codes: F02D 41/26 using computer, e.g. microprocessor
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: F02D 41/30 Controlling fuel injection F02D41/182, F02D41/24 take precedence
• CPC Class Codes: F02P 5/045 combined with electronic control of other engine functions, e.g. fuel injection in general F02D37/02
• CPC Class Codes: F02P 5/1512 with particular means concerning an individual cylinder
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines based on skip fire operation of the engine are described.

Claims

1. A method of controlling the operation of a vehicle that includes a continuously variable transmission and an engine having at least one least one working chamber, each working chamber being generally arranged to operate in a succession of working cycles, the method comprising:

operating the engine in a skip fire mode that skips the firing of selected skipped working cycles and fires selected active working cycles, wherein an amount of air and fuel that is substantially optimized for fuel efficiency is delivered to the working chambers during the active working cycles; and

controlling the continuously variable transmission such that during operation in the skip fire mode the engine operates at a rotational speed that is substantially optimized for fuel efficiency; and

whereby when the engine is operated in the skip fire mode, a majority of the active working cycles are operated in a condition that is substantially optimized for fuel efficiency.

2. A power train controller for controlling the operation of a vehicle having an internal combustion engine and a transmission, the internal combustion engine having a plurality of working chambers, each working chamber being generally arranged to operate in a succession of working cycles, the engine controller comprising:

firing sequence determining logic arranged to determine a firing sequence that includes skipped working cycles and active working cycles during operation of the engine in a skip fire mode; and

transmission control logic arranged to control the transmission such that during operation in the skip fire mode the engine operates at a rotational speed that is substantially optimized for fuel efficiency; and

firing control logic arranged to direct the firing of the working chambers in the determined firing sequence.

3. A power train controller as recited in claim 2, wherein the transmission is a continuously variable transmission.

4. A power train controller as recited in claim 2 wherein the firing pattern determining logic is arranged to determine the timing of the skips and fires on a working cycle by working cycle basis.

5. A power train controller as recited in claim 4 wherein the firing pattern determining logic includes a sigma delta converter that determines the timing of the skips and fires.

6. An internal combustion engine comprising:

a power train controller as recited in claim 2;

a plurality of working chambers each arranged to operate in a succession of working cycles;

a air delivery system arranged to facilitate the delivery of air into the working chambers; and

a fuel delivery system arranged to facilitate the delivery of fuel into the working chambers.

7. A vehicle comprising:

an internal combustion engine as recited in claim 6;

a continuously variable transmission; and

a plurality of wheels, wherein at least some of the wheels are driven by the engine through the continuously variable transmission.

8. A skip fire method of controlling the operation of an internal combustion engine having a plurality of working chambers, each working chamber being generally arranged to operate in a succession of working cycles, the method comprising:

determining a skip fire firing sequence during operation of the engine that identifies active working cycles and working cycles to be skipped;

delivering pressurized air to the working chambers for use during active working cycles, wherein the pressurized air is provided by a supercharger or turbocharger, such that during active working cycles, more air is delivered to the working chamber than would be provided by unthrottled air delivery at atmospheric pressure;

delivering fuel to the working chambers for use during active working cycles; and

firing the working chambers in the determined firing sequence, whereby during operation, a particular working chamber may be fired during one working cycle, skipped the next working cycle and either fired or skipped during the following working cycle.

9. An engine controller for controlling the operation of an internal combustion engine having at least one working chamber, each working chamber being generally arranged to operate in a succession of working cycles, the engine controller comprising:

firing sequence determining logic arranged to determine a firing sequence that includes skipped working cycles and active working cycles;

air and fuel delivery logic arranged to direct the delivery of pressurized air to the working chambers for use during active working cycles, wherein the pressurized air is provided by a supercharger or turbocharger, such that during active working cycles, more air is delivered to the working chamber than would be provided by unthrottled air delivery at atmospheric pressure; and

firing control logic arranged to direct the firing of the working chambers in the determined firing sequence.

10. An engine controller as recited in claim 9 wherein the firing pattern determining logic is arranged to determine the timing of the skips and fires on a working cycle by working cycle basis.

11. An engine controller as recited in claim 10 wherein the firing pattern determining logic includes a sigma delta converter that determines the timing of the skips and fires.

12. An engine controller for controlling skip fire operation of an internal combustion engine having at least one working chamber, each working chamber being generally arranged to operate in a succession of working cycles, the engine controller comprising:

skip fire firing timing determining logic arranged to determine a firing sequence that includes skipped working cycles and active working cycles;

a sequencer arranged to insure that over time, all of the cylinders are fired substantially the same amount while operating in the skip fire mode.