US 2010/0059015 A1 · Multi-stroke internal combustion engine

Abstract

An engine system and method of its operation are described. The method includes: operating the combustion chamber in a four stroke cycle by repeatedly opening a first exhaust valve of the combustion chamber once every four piston strokes while holding closed a second exhaust valve of the combustion chamber; after operating the combustion chamber in the four stroke cycle, operating the combustion chamber in a two stroke cycle by repeatedly opening the first exhaust valve once every four piston strokes and repeatedly opening the second exhaust valve once every four piston strokes during a different exhaust stroke than the first exhaust valve; and after operating the combustion chamber in the two stroke cycle, operating the combustion chamber in the four stroke cycle by repeatedly opening the second exhaust valve of the combustion chamber once every four piston strokes while holding closed the first exhaust valve of the combustion chamber.

Claims20

Dependent claims

A method of operating an internal combustion engine including at least one combustion chamber having a piston disposed therein, the method comprising:

repeatedly opening a first intake valve of the combustion chamber once every four piston strokes and repeatedly opening a first exhaust valve of the combustion chamber once every four piston strokes during a different stroke than the first intake valve;
transitioning operation of the combustion chamber from a four stroke cycle to a two stroke cycle by:
activating a second intake valve of the combustion chamber to repeatedly open once every four piston strokes during a different intake stroke than the first intake valve;
activating a second exhaust valve of the combustion chamber to repeatedly open once every four piston strokes during a different exhaust stroke than the first exhaust valve;
advancing an opening timing of the first intake valve;
and
retarding an opening timing of the first exhaust valve.

4 more elements

An internal combustion engine system for a vehicle, comprising:

an engine body defining at least one combustion chamber having a piston disposed therein;
a manifold coupled to the engine body and defining a fluid passage that communicates with the combustion chamber via a first valve and a second valve;
a first cam actuator configured to open the first valve;
a second cam actuator configured to open the second valve;
and
a control system configured to:
operate the first cam actuator to repeatedly open the first valve once every four piston strokes and operate the second cam actuator to repeatedly open the second valve once every four piston strokes during a different stroke than the first valve to carry out combustion in the combustion chamber according to a two stroke cycle;
and
transition the combustion chamber from the two stroke cycle to a four stroke cycle by deactivating the second valve while adjusting an opening timing of the first valve.

6 more elements

Dependencies are inferred from the claim text.

Multi-stroke internal combustion engine

Life of this patent

Multi-stroke internal combustion engine

Life of this patent

Abstract

Claims20