Three and two half stroke freeboost internal combustion engine
OwnerDavid S. Wellsinventor
Life of this patent
Estimating the term…
Abstract
A method and apparatus is provided for operating a piston driven, internal combustion engine (10) including a the piston (40) translating in a cylinder (30). The engine (10) has an intake stroke, followed by a partial exhaust stroke, followed by a compression stroke, followed by a power stroke and then an exhaust stroke, all of which are sequentially repeated. The compression stroke has a stroke length that is less than the stroke length of the power stroke.
Claims20
A method of operating a piston driven, internal combustion engine including a piston translating in a cylinder between a top dead center position and a bottom dead center position, an intake valve to the cylinder having an open state and a closed state, and an exhaust valve from the cylinder having an open state and a closed state;
- the method comprising the sequential steps of:
- (a) operating the intake valve to be in the open state and the exhaust valve to be in the closed state for at least a portion of an intake stroke wherein the piston moves from the top dead center position to the bottom dead center position;
- (b) operating the intake valve to be in the closed state and the exhaust valve to be in the open state for at least a portion of a partial exhaust stroke wherein the piston moves from the bottom dead center position to a partial stroke position between the bottom dead center position and the top dead center;
- (c) operating the intake valve to be in the closed state and the exhaust valve to be in the closed state for at least a portion of a compression stroke wherein the piston moves from the partial stroke position to the top dead center position;
- (d) operating the engine to combust a fuel/air mixture in the cylinder and operating the intake valve to be in the closed state and the exhaust valve to be in the closed state for at least a portion of a power stroke wherein the piston is driven from the top dead center position to the bottom dead center position;
- (e) operating the intake valve to be in the closed state and the exhaust valve to be in the open state for at least a portion of an exhaust stroke wherein the piston moves from the bottom dead center position to the top dead center position;
- and
- (f) sequentially repeating steps (a) through (e).
A method of operating a piston driven, internal combustion engine including a piston translating in a cylinder between a top dead center position and a bottom dead center position, an intake valve to the cylinder having an open state and a closed state, and an exhaust valve from the cylinder having an open state and a closed state, the piston connected by a crank to a crankshaft that rotates 180 degrees in response to the piston moving from the top dead center position to the bottom dead center position and that rotates another 180 degrees in response to the piston moving from the bottom dead center position to the top dead center position;
- the method comprising the sequential steps of:
- (a) operating the intake valve to be in the open state and the exhaust valve to be in the closed state for at least part of the 180 degrees of crankshaft rotation as the piston move from the top dead center position to the bottom dead center position during an intake stroke of the piston;
- (b) operating the intake valve to be in the closed state and the exhaust valve to be in the open state during less than 90 degrees of crankshaft rotation as the piston moves from the bottom dead center position to a partial stroke position between the bottom dead center position and the top dead center position during a partial exhaust stroke;
- (c) operating the intake valve to be in the closed state and the exhaust valve to be in the closed state during more than 90 degrees of crankshaft rotation as the piston moves from the partial stroke position to the top dead center position during a compression stroke;
- (d) operating the engine to combust a fuel/air mixture in the cylinder and operating the intake valve to be in the closed state and the exhaust valve to be in the closed state for at least part of the 180 degrees of crankshaft rotation as the piston is driven from the top dead center position to the bottom dead center position during a power stroke;
- (e) operating the intake valve to be in the closed state and the exhaust valve to be in the open state for at least part of the 180 degrees of crankshaft rotation as the piston moves from the bottom dead center position to the top dead center position during an exhaust stroke;
- and
- (f) sequentially repeating steps (a) through (e).
A method of operating a piston driven, internal combustion engine including a piston translating in a cylinder, an intake valve to the cylinder having an open state and a closed state, and an exhaust valve from the cylinder having an open state and a closed state, the piston having an intake stroke with an intake stroke length LI wherein air is drawn into the cylinder through the intake valve with the intake valve in the open state, a compression stroke with a compression stroke length LC wherein air within the cylinder is compressed, a power stroke with a power stroke length LP wherein the piston transfers power generated by a combustion of the compressed air with a fuel in the cylinder, and an exhaust stroke length LE wherein products of the combustion are forced from the cylinder through the exhaust valve with the exhaust valve in the open state;
- the method comprises operating the inlet and outlet valves of the engine so that the piston has a partial exhaust stroke between the intake stroke and the compression stroke, with a partial exhaust stroke length LPE, wherein the intake valve is in the closed state and the exhaust valve is in the open state.
An internal combustion engine comprising:
- a piston mounted for translation in a cylinder between a top dead center position and a bottom dead center position;
- an intake valve to the cylinder, the intake valve having an open state and a closed state;
- an exhaust valve from cylinder, the exhaust valve having an open state and a closed state;
- and wherein the engine is configured to automatically operate the intake and the exhaust valves to sequentially achieve:
- (a) an intake stroke wherein the piston moves from the top dead center position to the bottom dead center position with the intake valve in the open state and the exhaust valve in the closed state for at least a portion of the intake stroke;
- (b) a partial exhaust stroke wherein the piston moves from the bottom dead center position to a partial stroke position between the bottom dead center position and the top dead center position with the intake valve in the closed state and the exhaust valve in the open state for at least a portion of the partial exhaust stroke;
- (c) a compression stroke wherein the piston moves from the partial stroke position to the top dead center position with the intake valve in the closed state and the exhaust valve in the closed state for at least a portion of the compression stroke;
- (d) a power stroke wherein the piston is driven from the top dead center position to the bottom dead center position following a combustion of a fuel/air mixture in the cylinder, with the intake valve in the closed state and the exhaust valve in the closed state for at least a portion of the power stroke;
- and
- (e) an exhaust stroke wherein the piston moves from the bottom dead center position to the top dead center position with the intake valve in the closed state and the exhaust valve in the open state for at least a portion of the exhaust stroke.
Dependencies are inferred from the claim text.