US 6,474,291 B2 · Clean shutdown for internal combustion engine with variable valve timing · patentgrep

Loading patent…

Abstract

A four-stroke internal combustion engine is disclosed wherein fuel and exhaust vapors are purged from the manifolds and each cylinder when the engine is shut down to minimize emissions on subsequent startup. The engine includes a cylinder, a reciprocating piston within the cylinder, and a cylinder head. An exhaust port with an exhaust valve communicates with the cylinder and an exhaust manifold with an emissions control device. An intake port with an intake valve communicates with the cylinder. Upon engine shutdown, a controller sends signals to a variable valve timing system for opening the exhaust valve when the piston is in upward motion, later closing the exhaust valve when the piston is in upward motion, opening the intake valve when the piston is in downward motion, later closing the intake valve when the piston is in downward motion, and opening the exhaust valve when the piston is in upward motion.

Claims30

Dependent claims

A four-stroke reciprocating internal combustion engine comprising:

a combustion chamber defined by a cylinder, a reciprocating piston contained within the cylinder, and a cylinder head;
an exhaust port in fluid communication with the combustion chamber and an exhaust manifold, the exhaust port including an exhaust valve, the exhaust manifold being in fluid communication with an emissions control device;
an intake port in fluid communication with the combustion chamber, the intake port being in fluid communication with a fuel injector for directing fuel into air in the intake port to form an air-fuel mixture, the intake port including an intake valve, the cylinder including a spark device for igniting the air-fuel mixture introduced into the combustion chamber through the intake port;
at least one sensor for sensing at least one engine operating condition;
and
a controller, responsive to each sensor, for providing fuel injector control signals to the fuel injector for operating the fuel injector, for providing spark device control signals to the spark device for operating the spark device, and for providing valve control signals to a variable valve timing system for operating the exhaust valve and the intake valve, the controller executing a stored program to:
(a) sense when the engine is in a shutdown condition,
(b) thereafter cease fuel injection from the fuel injector,
(c) thereafter operate the spark device to ignite the air-fuel mixture in the combustion chamber,
(d) thereafter open the exhaust valve, and
(e) thereafter close the exhaust valve after the reciprocating piston has been in upward motion for a time period, and
(f) thereafter open the intake valve when the reciprocating piston is in downward motion,
(g) thereafter close the intake valve after the reciprocating piston has been in downward motion for a time period, and
(h) thereafter open the exhaust valve when the reciprocating piston is in upward motion.

11 more elements

A four-stroke reciprocating internal combustion engine comprising:

at least two combustion chambers, each combustion chamber being defined by a cylinder, a reciprocating piston contained within the cylinder, and a cylinder head;
an exhaust port in fluid communication with each combustion chamber, each exhaust port including an exhaust valve, each exhaust port being in fluid communication with an exhaust manifold, the exhaust manifold being in fluid communication with an emissions control device;
an intake port associated with and in fluid communication with each combustion chamber, each intake port being in fluid communication with a fuel injector for directing fuel into air in the intake port to form an air-fuel mixture, each intake port including an intake valve, each cylinder including a spark device for igniting the air-fuel mixture introduced into each combustion chamber through its associated intake port;
at least one sensor for sensing at least one engine operating condition;
and
a controller, responsive to each sensor, for providing fuel injector control signals to each fuel injector for operating each fuel injector, for providing spark device control signals to each spark device for operating each spark device, and for providing valve control signals to a variable valve timing system for operating each exhaust valve and each intake valve, the controller executing a stored program to:
(a) sense when the engine is in a shutdown condition,
(b) thereafter cease fuel injection from each fuel injector and identify a last injected combustion chamber wherein the associated intake port was receiving or had last received fuel from the fuel injector when the controller sensed that the engine was in a shutdown condition,
(c) thereafter operate the spark device associated with the last injected combustion chamber to ignite the air-fuel mixture in the last injected combustion chamber,
(d) open each exhaust valve of each combustion chamber other than the last injected combustion chamber when each reciprocating piston is in upward motion,
(e) thereafter close each exhaust valve of each combustion chamber other than the last injected combustion chamber after each reciprocating piston has been in upward motion for a time period,
(f) open each intake valve of each combustion chamber other than the last injected combustion chamber when each reciprocating piston is in downward motion,
(g) thereafter close each intake valve of each combustion chamber other than the last injected combustion chamber after each reciprocating piston has been in downward motion for a time period,
(h) thereafter open each exhaust valve of each combustion chamber other than the last injected combustion chamber when each reciprocating piston is in upward motion,
(i) after the spark device has ignited the air-fuel mixture in the last injected combustion chamber, cease operation of the spark device and open the exhaust valve of the last injected combustion chamber,
(j) thereafter close the exhaust valve of the last injected combustion chamber after its associated reciprocating piston has been in upward motion for a time period,
(k) thereafter open the intake valve of the last injected combustion chamber when its associated reciprocating piston is in downward motion,
(l) thereafter close the intake valve of the last injected combustion chamber after its associated reciprocating piston has been in downward motion for a time period, and
(m) thereafter open the exhaust valve of the last injected combustion chamber when its associated reciprocating piston is in upward motion.

16 more elements

A four-stroke reciprocating internal combustion engine comprising:

a combustion chamber defined by a cylinder, a reciprocating piston contained within the cylinder, and a cylinder head;
an exhaust port in fluid communication with the combustion chamber and an exhaust manifold, the exhaust port including an exhaust valve, the exhaust manifold being in fluid communication with an emissions control device;
an intake port in fluid communication with the combustion chamber for directing intake air into the combustion chamber, the intake port including an intake valve;
a fuel injector in fluid communication with the combustion chamber, the fuel injector being positioned to direct fuel into the intake air to create an air-fuel mixture;
a spark device located in the cylinder for igniting the air-fuel mixture in the combustion chamber;
at least one sensor for sensing at least one engine operating condition;
and
a controller, responsive to each sensor, for providing fuel injector control signals to the fuel injector for operating the fuel injector, for providing spark device control signals to the spark device for operating the spark device, and for providing valve control signals to a variable valve timing system for operating the exhaust valve and the intake valve, the controller executing a stored program to:
(a) sense when the engine is in a shutdown condition,
(b) thereafter cease fuel injection from the fuel injector,
(c) thereafter operate the spark device to ignite the air-fuel mixture in the combustion chamber,
(d) thereafter open the exhaust valve,
(e) thereafter close the exhaust valve after the reciprocating piston has been in upward motion for a time period, and
(f) thereafter open the intake valve when the reciprocating piston is in downward motion,
(g) thereafter close the intake valve after the reciprocating piston has been in downward motion for a time period, and
(h) thereafter open the exhaust valve when the reciprocating piston is in upward motion.

13 more elements

A four-stroke reciprocating internal combustion engine comprising:

at least two combustion chambers, each combustion chamber being defined by a cylinder, a reciprocating piston contained within the cylinder, and a cylinder head;
an exhaust port in fluid communication with each combustion chamber, each exhaust port including an exhaust valve, each exhaust port being in fluid communication with an exhaust manifold, the exhaust manifold being in fluid communication with an emissions control device;
an intake port associated with and in fluid communication with each combustion chamber for directing intake air into the combustion chamber, each intake port including an intake valve;
a fuel injector in fluid communication with each combustion chamber, each fuel injector being positioned to direct fuel into the intake air in each combustion chamber to create an air-fuel mixture in each combustion chamber;
a spark device located in each cylinder for igniting the air-fuel mixture in each combustion chamber;
at least one sensor for sensing at least one engine operating condition;
and
a controller, responsive to each sensor, for providing fuel injector control signals to each fuel injector for operating each fuel injector, for providing spark device control signals to each spark device for operating each spark device, and for providing valve control signals to a variable valve timing system for operating each exhaust valve and each intake valve, the controller executing a stored program to:
(a) sense when the engine is in a shutdown condition,
(b) thereafter cease fuel injection from each fuel injector and identify a last injected combustion chamber wherein the combustion chamber was receiving or had last received fuel from the fuel injector when the controller sensed that the engine was in a shutdown condition,
(c) thereafter operate the spark device associated with the last injected combustion chamber to ignite the air-fuel mixture in the last injected combustion chamber,
(d) open each exhaust valve of each combustion chamber other than the last injected combustion chamber when each reciprocating piston is in upward motion,
(e) thereafter close each exhaust valve of each combustion chamber other than the last injected combustion chamber after each reciprocating piston has been in upward motion for a time period,
(f) open each intake valve of each combustion chamber other than the last injected combustion chamber when each reciprocating piston is in downward motion,
(g) thereafter close each intake valve of each combustion chamber other than the last injected combustion chamber after each reciprocating piston has been in downward motion for a time period,
(h) thereafter open each exhaust valve of each combustion chamber other than the last injected combustion chamber when each reciprocating piston is in upward motion,
(i) after the spark device has ignited the air-fuel mixture in the last injected combustion chamber, cease operation of the spark device and open the exhaust valve of the last injected combustion chamber,
(j) thereafter close the exhaust valve of the last injected combustion chamber after its associated reciprocating piston has been in upward motion for a time period,
(k) thereafter open the intake valve of the last injected combustion chamber when its associated reciprocating piston is in downward motion,
(l) thereafter close the intake valve of the last injected combustion chamber after its associated reciprocating piston has been in downward motion for a time period, and
(m) thereafter open the exhaust valve of the last injected combustion chamber when its associated reciprocating piston is in upward motion.

18 more elements

A four-stroke reciprocating internal combustion engine comprising:

a combustion chamber defined by a cylinder, a reciprocating piston contained within the cylinder, and a cylinder head;
an exhaust port in fluid communication with the combustion chamber and an exhaust manifold, the exhaust port including an exhaust valve, the exhaust manifold being in fluid communication with an emissions control device;
an intake port in fluid communication with the combustion chamber for directing intake air into the combustion chamber, the intake port including an intake valve;
a fuel injector positioned for directing fuel into intake air in the intake port or positioned for directing fuel into intake air in the combustion chamber to form an air-fuel mixture;
a spark device for igniting the air-fuel mixture in the combustion chamber;
at least one sensor for sensing at least one engine operating condition;
and
a controller, responsive to each sensor, for providing fuel injector control signals to the fuel injector for operating the fuel injector, for providing spark device control signals to the spark device for operating the spark device, and for providing valve control signals to a variable valve timing system for operating the exhaust valve and the intake valve, the controller executing a stored program to:
(a) sense when the engine is in a shutdown condition,
(b) thereafter cease fuel injection from the fuel injector,
(c) thereafter operate the spark device to ignite the air-fuel mixture in the combustion chamber,
(d) thereafter open the exhaust valve, and
(e) thereafter close the exhaust valve after the reciprocating piston has been in upward motion for a time period, and
(f) thereafter open the intake valve when the reciprocating piston is in downward motion,
(g) thereafter close the intake valve after the reciprocating piston has been in downward motion for a time period, and
(h) thereafter open the exhaust valve when the reciprocating piston is in upward motion.

13 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/740,593Filed 19 Dec 2000
Published: US 2002/0073955 A120 Jun 2002
Granted: 5 Nov 2002
Term ends: Not estimatedThe source records don’t support an estimate.

Classification14 codes

F02D 41/042
Introducing corrections for particular operating conditions: for stopping the engine
F01L 9/20
Valve-gear or valve arrangements actuated non-mechanically: by electric means
F02D 13/0207
Variable control of intake and exhaust valves: changing valve lift or valve lift and timing
F02D 13/08
Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing: for rendering engine inoperative or…

Family

US 2002/0073955 A1Pre-grant publication · published 20 Jun 2002
US 6,474,291 B2This patent

From the US filing history. Foreign family members aren’t listed.

Timeline

Citations

Open elsewhere