Variable displacement engine

A combustion engine, comprising:

• a main combustion cylinder;
• a main valve in the main combustion cylinder;
• an upper non-combustion chamber in gas communication with the main combustion cylinder;
• an upper intake valve in the upper non-combustion chamber;
• and
• an upper exhaust valve in the upper non-combustion chamber;
• wherein the main valve, the upper intake valve, and the upper exhaust valve are configured to move independently of one another in a timed manner;
• wherein the main valve, the upper intake valve, and the upper exhaust valve are configured to operate in a blow back mode;
• wherein, in the blow back mode, the upper intake valve is further configured to transfer exhaust gas to an intake manifold.

A combustion engine, comprising:

• a main combustion cylinder;
• a main valve in the main combustion cylinder;
• an upper non-combustion chamber configured to operate, with the main combustion cylinder, in an intake mode, in a compression mode, and in an exhaust mode;
• an upper intake valve in the upper non-combustion chamber;
• and
• an upper exhaust valve in the upper non-combustion chamber;
• wherein the main valve is configured to always maintain a fixed timing at the same time that one of a timing of the upper intake valve and a timing of the upper exhaust valve is varied.

A computer implemented method of varying a displacement of a combustion engine, comprising:

• controlling, by a controller, a timing of an upper intake valve in an upper non-combustion chamber of an engine block of the combustion engine;
• controlling, by the controller, a timing of an upper exhaust valve in the upper non-combustion chamber;
• and
• controlling, by the controller, a timing of a main valve in a main combustion cylinder of the engine block;
• wherein the main valve timing, the upper intake valve timing, and the upper exhaust valve timing are controlled independently of one another;
• wherein the main valve timing is always fixed at the same time that one of the upper intake valve timing and the upper exhaust valve timing is varied.

A non-transitory computer readable medium with executable instructions stored thereon, executed by a processor, to perform a method for varying a displacement of a combustion engine, the method comprising:

• changing at least one of:
• a timing of an upper intake valve in an upper non-combustion chamber of an engine block of the combustion engine;
• and
• a timing of an upper exhaust valve in the upper non-combustion chamber;
• and
• fixing a timing of a main valve in a main combustion cylinder of the engine block;
• wherein the main combustion cylinder is in gas communication with the upper non-combustion chamber;
• wherein changing at least one of the timing of the upper intake valve and the timing of the upper exhaust valve occur independently of one another;
• wherein varying the displacement of the combustion engine includes operating the combustion engine in a blow back mode;
• wherein, in the blow back mode, the upper intake valve is further configured to transfer exhaust gas to an intake manifold.

A non-transitory computer readable medium with executable instructions stored thereon, executed by a processor, to perform a method for operating a combustion engine in a full displacement mode, the method comprising:

• fixing an upper intake valve in a neutral timing, wherein the upper intake valve is in an upper non-combustion chamber of an engine block of the combustion engine in a neutral timing;
• and
• fixing an upper exhaust valve in the neutral timing, wherein the upper exhaust valve is in the upper non-combustion chamber;
• and
• fixing a timing of a main valve in a main combustion cylinder of the engine block;
• wherein the neutral timing of the upper intake valve and of the upper exhaust valve overlap with the timing of the main valve;
• fixing a valve duration of the upper intake valve that is greater than a valve duration of the main valve;
• fixing a valve duration of the upper exhaust valve at greater than the valve duration of the main valve;
• wherein, in an exhaust stroke of a previous cycle of the combustion engine, and after a piston of the combustion engine reaches a bottom dead center (BDC) position, the main valve opens, the upper exhaust valve opens, the piston pushes exhaust gas into the upper non-combustion chamber, and then into an exhaust manifold of the combustion engine;
• wherein, in a late stage of the exhaust stroke of the previous cycle, the upper intake valve opens, intake air pushes the exhaust gas out of the upper non-combustion chamber and to the upper exhaust valve, and then into an exhaust manifold of the combustion engine;
• wherein, in an intake stroke of a next cycle of the combustion engine, the upper exhaust valve closes, the main valve opens, and the piston draws the intake air into the main combustion cylinder;
• wherein, in a compression stroke of the next cycle, the intake air is compressed in the main combustion cylinder and is ready for combustion burning;
• and
• wherein, in a power stroke of the next cycle, the upper intake valve closes, the upper exhaust valve closes, the main valve closes, and combustion pushes the piston to turn a crankshaft of the combustion engine.

A non-transitory computer readable medium with executable instructions stored thereon, executed by a processor, to perform a method for operating a combustion engine in a partial displacement mode, the method comprising:

• fixing an upper intake valve in a neutral timing, wherein the upper intake valve is in an upper non-combustion chamber of an engine block of the combustion engine;
• fixing an upper exhaust valve in an advanced timing, wherein the upper exhaust valve is in the upper non-combustion chamber;
• fixing a timing of a main valve in a main combustion cylinder of the engine block;
• wherein the neutral timing of the upper intake valve overlaps with the timing of the main valve;
• wherein the advanced timing of the upper exhaust valve causes the upper exhaust valve to open and close in advance of the main valve opening and closing;
• wherein the advanced timing of the upper exhaust valve decreases timing overlap with the main valve during an exhaust stroke;
• wherein, in an exhaust stroke of a previous cycle of the combustion engine, the upper exhaust valve opens before a piston reaches a bottom dead center (BDC) position;
• and after the piston reaches the BDC position, the main valve opens and the piston pushes exhaust gas out of the main combustion cylinder, into the upper non-combustion chamber, and then out into an exhaust manifold of the combustion engine;
• wherein, in a late stage of the exhaust stroke of the previous cycle, the upper exhaust valve and the upper intake valve close, the main valve is open, and the piston pushes exhaust gas into the upper non-combustion chamber;
• wherein, in an intake stroke of a next cycle of the combustion engine, the upper intake valve opens before the piston reaches a top dead center (TDC) position and before beginning of the intake stroke, the upper exhaust valve is closed and the main valve opens at the beginning of the intake stroke, and the piston draws exhaust gas and then intake air from the upper non-combustion chamber and into the main combustion cylinder;
• wherein, in a compression stroke of the next cycle, the upper intake valve, the upper exhaust valve and the main valve are closed;
• the intake air is compressed with the exhaust gas in the main combustion cylinder and is ready for combustion burning;
• wherein, in a power stroke of the next cycle, the upper intake valve, the upper exhaust valve and the main valve are closed;
• and combustion pushes the piston to turn a crankshaft of the combustion engine.

A non-transitory computer readable medium with executable instructions stored thereon, executed by a processor, to perform a method for operating a combustion engine in a blow back mode, the method comprising:

• fixing an upper intake valve in a neutral timing, wherein the upper intake valve is in an upper non-combustion chamber of an engine block of the combustion engine;
• and
• fixing an upper exhaust valve in an advanced timing, wherein the upper exhaust valve is in the upper non-combustion chamber;
• fixing a timing of a main valve in a main combustion cylinder of the engine block;
• wherein the upper exhaust valve opens before a bottom dead center (BDC) position of a piston of the combustion engine
• wherein the neutral timing of the upper intake valve overlaps with the timing of the main valve;
• wherein a valve duration of the upper intake valve is greater than a valve duration of the main valve;
• wherein, in an exhaust stroke of a previous cycle of the combustion engine, the piston pushes exhaust gas into the upper non-combustion chamber and out to an exhaust manifold;
• wherein, in a late stage of the exhaust stroke of the previous cycle, the upper exhaust valve closes, the upper intake valve opens, and exhaust gas flows from the main combustion cylinder and into the upper non-combustion chamber and then to an intake manifold of the combustion engine, whereby the intake manifold acts as a reservoir for the exhaust gas and intake air for a next cycle;
• wherein, in an intake stroke of the next cycle, the piston draws the exhaust gas and the intake air from the intake manifold, through the upper non-combustion chamber and into the main combustion cylinder;
• wherein, in a compression stroke of the next cycle, the upper exhaust valve, the upper intake valve, and the main valve are closed;
• the intake air is compressed with the exhaust gas in the main combustion cylinder and are ready for combustion burning;
• wherein, in a power stroke of the next cycle, the upper exhaust valve, the upper intake valve, and the main valve are closed;
• and combustion pushes the piston to turn a crankshaft of the combustion engine.

A non-transitory computer readable medium with executable instructions stored thereon, executed by a processor, to perform a method for operating a combustion engine in an Atkinson cycle mode, the method comprising:

• fixing an upper intake valve in an advanced timing, wherein the upper intake valve is in an upper non-combustion chamber of an engine block of the combustion engine;
• fixing an upper exhaust valve in a neutral timing, wherein the upper exhaust valve is in the upper non-combustion chamber;
• fixing a main valve in a neutral timing, wherein the main valve is in a main combustion cylinder of the engine block;
• wherein the neutral timing of the upper exhaust valve allows exhaust gas to fully flow out the main combustion cylinder and into the upper non-combustion chamber via the main valve;
• wherein the advanced timing of the upper intake valve allows the upper intake valve to open during an exhaust cycle of the combustion engine;
• wherein overlap of openings of the upper exhaust valve and the upper intake valve at the same time enables exhaust gas to pull intake air into an exhaust manifold of the combustion engine via the upper intake valve, the upper non-combustion chamber, and the upper exhaust valve;
• whereby the intake air replaces exhaust gas in the upper non-combustion chamber;
• whereby exhaust gas exits the combustion engine via the upper exhaust valve;
• wherein, in an early closing of upper intake valve during an intake stroke of the combustion engine, decreased gas volume enters the main combustion cylinder and there is a smaller compression stroke than an expansion stroke of the combustion engine.