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US 12,012,910 B2Granted
Air-cooled, four-stroke aviation engine
AssigneeTextron Innovations Inc.
InventorsPatrick Henry Baer, Michael Glynn Glucksman
Life of this patent
Estimating the term…
Abstract
An improved air-cooled aviation engine includes a compact combustion chamber having an intake valve opening, an exhaust valve opening, and a generally elliptical shape. The elliptical shape has a major axis and a minor axis, with the major axis intersecting both the intake valve opening and the exhaust valve opening. In some examples, the major axis is the same length or shorter than a diameter of a cylinder bore of the engine, and the minor axis is smaller than the major axis. Combustion is thus constrained to a smaller area than that of the cylinder bore.
Claims21
An air-cooled aviation engine, comprising:
- a cylinder head having an intake valve opening, an exhaust valve opening, a plurality of spark plugs, and an interior surface;
- a cylinder bore having a cross-sectional area and containing a piston configured to move reciprocally within the cylinder bore;
- a combustion chamber having an upper region defined by the interior surface of the cylinder head and a lower region defined by the piston when the piston is in an uppermost position within the cylinder bore;
- an intake valve arranged to selectively admit intake air into the combustion chamber via the intake valve opening, the intake valve having an intake valve stem and an intake valve head;
- and
- an exhaust valve arranged to selectively allow exhaust gases to be expelled from the combustion chamber via the exhaust valve opening, the exhaust valve having an exhaust valve stem and an exhaust valve head,
- wherein the combustion chamber has an elliptical shape that extends over a cross-sectional area smaller than the cross-sectional area of the cylinder bore, the elliptical shape having a major axis that intersects the intake valve opening and the exhaust valve opening,
- wherein each of the intake valve stem and the exhaust valve stem includes a triple-bead attachment to a respective valve retainer, each triple-bead attachment constructed and arranged to facilitate rotation of a respective valve within the respective valve retainer, and
- wherein the air-cooled aviation engine further comprises:
- a first spring disposed between an intake valve retainer and a first spring seat of the cylinder head, the first spring being constructed and arranged to incrementally rotate the intake valve within an intake valve retainer on successive compressions of the first spring;
- and
- a second spring disposed between an exhaust valve retainer and a second spring seat of the cylinder head, the second spring being constructed and arranged to incrementally rotate the exhaust valve within an exhaust valve retainer on successive compressions of the second spring.
9 more elements
An air-cooled aviation engine, comprising multiple cylinders, each cylinder including:
- a cylinder head having an intake valve opening, an exhaust valve opening, a plurality of spark plugs, and an interior surface;
- a cylinder bore having a cross-sectional area and containing a piston configured to move reciprocally within the cylinder bore;
- and
- a combustion chamber having an upper region defined by the interior surface of the cylinder head and a lower region defined by the piston when the piston is in an uppermost position within the cylinder bore;
- an intake valve arranged to selectively admit intake air into the combustion chamber via the intake valve opening, the intake valve having an intake valve stem and an intake valve head;
- and
- an exhaust valve arranged to selectively allow exhaust gases to be expelled from the combustion chamber via the exhaust valve opening, the exhaust valve having an exhaust valve stem and an exhaust valve head,
- wherein the combustion chamber has an elliptical shape that extends over a cross-sectional area smaller than the cross-sectional area of the cylinder bore, the elliptical shape having a major axis that intersects the intake valve opening and the exhaust valve opening,
- wherein each of the intake valve stem and the exhaust valve stem includes a triple-bead attachment to a respective valve retainer, each triple-bead attachment constructed and arranged to facilitate rotation of a respective valve within the respective valve retainer, and
- wherein the air-cooled aviation engine further comprises:
- a first spring disposed between an intake valve retainer and a first spring seat of the cylinder head, the first spring being constructed and arranged to incrementally rotate the intake valve within an intake valve retainer on successive compressions of the first spring;
- and
- a second spring disposed between an exhaust valve retainer and a second spring seat of the cylinder head, the second spring being constructed and arranged to incrementally rotate the exhaust valve within an exhaust valve retainer on successive compressions of the second spring.
10 more elements
An air-cooled aviation engine, comprising:
- a cylinder head having an intake valve opening, an exhaust valve opening, a plurality of spark plugs, and an interior surface;
- a cylinder bore having a cross-sectional area and containing a piston configured to move reciprocally within the cylinder bore;
- a combustion chamber having an upper region defined by the interior surface of the cylinder head and a lower region defined by the piston when the piston is in an uppermost position within the cylinder bore;
- an intake valve arranged to selectively admit intake air into the combustion chamber via the intake valve opening, the intake valve having an intake valve stem and an intake valve head, the intake valve stem having a diameter of less than 9 mm;
- and
- an exhaust valve arranged to selectively allow exhaust gases to be expelled from the combustion chamber via the exhaust valve opening, the exhaust valve having an exhaust valve stem and an exhaust valve head, the exhaust valve stem having a diameter of less than 9 mm,
- wherein the combustion chamber has an elliptical shape that extends over a cross-sectional area smaller than the cross-sectional area of the cylinder bore, the elliptical shape having a major axis that intersects the intake valve opening and the exhaust valve opening, and
- wherein the intake valve stem and the exhaust valve stem each have a triple-bead attachment to a respective valve retainer;
- wherein the air-cooled aviation engine further comprises:
- a first spring disposed between an intake valve retainer and a first spring seat of the cylinder head, the first spring being constructed and arranged to incrementally rotate the intake valve within an intake valve retainer on successive compressions of the first spring;
- and
- a second spring disposed between an exhaust valve retainer and a second spring seat of the cylinder head, the second spring being constructed and arranged to incrementally rotate the exhaust valve within an exhaust valve retainer on successive compressions of the second spring.
9 more elements
Dependencies are inferred from the claim text.