Engine operation using fully flexible valve and injection events

• US 5,117,790 A
• Filed: 02/19/1991
• Issued: 06/02/1992
• Est. Priority Date: 02/19/1991
• Status: Expired due to Term

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Clarke, John M., Faletti, James J.
• Primary Examiner(s): Nelli, Raymond A.
• Application Number:
  US07/656,653
• Time in Patent Office: 469 Days
• Field of Search: 123/90.11, 123/321, 123/64, 123/179 H, 123/568, 123/90.15, 123/179 B
• US Class Current: 123/321
• CPC Class Codes: F02B 1/04 with fuel-air mixture admission into cylinder
• CPC Class Codes: F02B 2075/025 two
• CPC Class Codes: F02B 2075/027 four
• 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 13/0203 Variable control of intake and exhaust valves
• CPC Class Codes: F02D 13/0215 changing the valve timing only
• CPC Class Codes: F02D 13/0234 changing the valve timing only
• CPC Class Codes: F02D 13/0253 Fully variable control of valve lift and timing using camless actuation systems such as hydraulic, pneumatic or electromagnetic actuators, e.g. solenoid valves
• CPC Class Codes: F02D 13/0269 Controlling the valves to perform a Miller-Atkinson cycle
• CPC Class Codes: F02D 13/0273 Multiple actuations of a valve within an engine cycle
• CPC Class Codes: F02D 13/028 for two-stroke engines
• CPC Class Codes: F02D 17/02 Cutting-out cutting-out engines in multiple engine arrangements F02D25/04
• CPC Class Codes: F02D 2041/001 for engines with variable valve actuation
• CPC Class Codes: F02D 2041/0012 with selective deactivation of cylinders
• CPC Class Codes: F02D 35/02 on interior conditions
• CPC Class Codes: F02D 35/023 by determining the cylinder pressure
• CPC Class Codes: F02D 41/008 Controlling each cylinder individually
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: F02D 41/3058 : the engine working with a variable number of cycles
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies

Abstract

A system for controlling operational modes of an engine including valve and injection events, in which the engine comprises a plurality of cylinders having an intake and exhaust valve, an injector, a chamber and an intake and exhaust port. The plurality of cylinders are connected by an intake and exhaust manifold. The system comprises a cylinder control unit for independently governing an operational mode of each of the cylinders. The cylinder control unit comprises a valve control unit for controlling the operation of the intake and exhaust valves. The cylinder control unit also controls opening and closing of the intake and exhaust valves in accordance with the independently governed operational mode of each cylinder. The cylinder control unit further comprises an injector control unit for controlling the operation of the each of the injectors. The injector control unit controls fuel injection timing of each of the injectors, independently of the operation of the intake and exhaust valves. The cylinder control unit independently controls each of the cylinders to control the valve and injection events to achieve a plurality of operational modes for the engine.

Claims

1. A system for controlling a plurality of operational modes of an engine including valve and injection events, in which the engine comprises a plurality of cylinders having an intake and exhaust valve, an injector, a chamber and an intake and exhaust port, wherein the plurality of cylinders are connected by an intake and exhaust manifold, said system comprising:

cylinder control means for governing an operational mode of each of the cylinders independently, including;

(a) valve control means for controlling the operation of the intake and exhaust valves, including controlling at least one of an opening and closing of the intake and exhaust valves in accordance with the independently governed operational mode of each cylinder; and

(b) injector control means for controlling the operation of each of the injectors, including controlling fuel injection timing of each of the injectors, independently of the operation of the intake and exhaust valves;

wherein said cylinder control means independently controls each of the cylinders to control the valve and injection events to responsively achieve a plurality of operational modes for the engine.

2. A method for controlling a plurality of operational modes of an engine including valve and injection events, in which the engine comprises a plurality of cylinders having an intake and exhaust valve, an injector, a chamber and an intake and exhaust port, wherein the plurality of cylinders are connected by an intake and exhaust manifold, said method comprising the steps of:

controlling, independently, a mode of operation for each of the cylinders by;

controlling at least one of an opening and closing of the intake and exhaust valves of a given cylinder independently of the operation of the intake and exhaust valves of the others of said plurality of cylinders; and

controlling fuel injection timing of the injector of said given cylinder independently of the opening and closing of the intake and exhaust valves of said given cylinder and of the operation of the injection of said other cylinders.

3. A method for controlling valve and injection events for an engine according to claim 2, further comprising the step of:

controlling the timing of said opening and closing of the intake and exhaust valves to control engine braking.

4. A method for controlling valve and injection events for faster upshifting of an engine according to claim 3, further comprising the step of:

placing the engine in a first operational load mode; and

switching at least one of the plurality of cylinders into a braking mode for reducing engine RPMs to permit instantaneous synchronous upshifting.

5. A method for controlling valve and injection events for an engine according to claim 2, further comprising the step of:

modifying said timing of said fuel injection to achieve split injection to reduce engine stress and noise.

6. A method to reduce the effective induction and compression strokes of the engine and achieve a modified engine air flow and compression ratio of an engine according to claim 2, further comprising the step of:

modifying the intake closing of the engine by performing one of;

(a) closing the intake valve during a late stage of an induction stroke; and

(b) closing the intake valve during an early stage of a compression stroke.

7. A method for controlling valve and injection events for an engine according to claim 2, further comprising the steps of:

opening the intake valve of at least one of the plurality of cylinders to draw air in through the corresponding intake port during an induction stroke of a cycle of the engine;

thereafter closing the intake valve; and

thereafter opening the exhaust valve during a compression stroke of said cycle to pump air through the exhaust port to operate the engine as a positive displacement pump.

8. A method for controlling valve and injection events for starting an engine according to claim 2, further comprising the steps of:

(1) placing the plurality of cylinders into a low work mode to permit low torque engine cranking;

(2) placing a subset of said plurality of cylinders into a first drag mode to inhibit air flow into a corresponding plurality of chambers;

(3) switching at least one cylinder into an air heating mode to heat air in a corresponding intake manifold and a corresponding chamber;

(4) switching said at least one cylinder into a normal operating mode;

(5) switching said plurality of cylinders into a second drag mode higher that said first drag mode;

(6) increasing fuel injection to said at least one cylinder to induce strong heating; and

(7) starting further cylinders by repeating steps 3-6.

9. A method for controlling valve and injection events for optimizing part load of an engine according to claim 2, further comprising the steps of:

placing at least one first cylinder into a high load mode; and

placing at least one second cylinder into a low drag mode to improve engine efficiency.

10. A method for controlling valve and injection events for fast engine response according to claim 2, further comprising the steps of:

(1) placing at least one first cylinder into a braking mode to absorb power and placing at least one second cylinder into a high load mode to increase exhaust temperature and provide a surplus of turbocharged air;

(2) conveying said surplus of turbocharged air to said at least one first cylinder; and

(3) switching said at least one first cylinder into a power mode to exploit said surplus of turbocharged air to improve engine response.

11. A method for controlling valve and injection events for an engine according to claim 2, further comprising the steps of:

placing the plurality of cylinders into a first mode of cycle operation; and

switching at least one of said plurality of cylinders into a second mode of cycle operation, said first mode of cycle operation being different from said second mode of cycle operation.

12. An internal combustion engine adapted to perform a plurality of operational modes including a combination of independent cylinder events, wherein said engine comprises:

a plurality of cylinders, connected by an intake and exhaust manifold, each cylinder comprising an intake and exhaust valve, an injector, a chamber, an intake and exhaust port;

means for governing at least a first cylinder of said plurality of cylinders in a first operational mode, wherein said first operational mode has a first ordered set of cylinder events; and

means for independently governing at least a second cylinder of said plurality of cylinders in a second operational mode, wherein said second operational mode has a second ordered set of cylinder events;

wherein said first ordered set of cylinder events is different from said second ordered set of cylinder events.

13. A method for controlling simultaneous firing of a plurality of cylinders of an internal combustion engine by scheduling of combustion events, comprising the steps of:

(1) placing two cylinders in a firing mode to cause substantially simultaneous blow-down;

(2) waiting approximately 240°

of crank shaft rotation;

(3) placing two further cylinders in a firing mode to cause additional substantially simultaneous blow-down; and

(4) repeating steps 2 and 3 to increase turbocharger speed at low engine speed.