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US 7,921,817 B2Granted
Internal combustion engine
AssigneeCleeves Engines Inc.
InventorJames M. Cleeves
Life of this patent
Estimating the term…
Abstract
An internal combustion engine is provided. Facing pistons eliminate a cylinder head, thereby reducing heat losses through a cylinder head. Facing pistons also halve the stroke that would be required for one piston to provide the same compression ratio, and the engine can thus be run at higher revolutions per minute and produce more power. An internal sleeve valve is provided for space and other considerations. A combustion chamber size-varying mechanism allows for adjustment of the minimum size of an internal volume to increase efficiency at partial-power operation. Variable intake valve operation is used to control engine power.
Claims24
An internal combustion engine, comprising:
- a body comprising a cylinder block;
- a piston disposed in a cylinder formed within the cylinder block;
- a port in the body to allow air and fuel into an internal volume within the cylinder;
- a drive shaft having a bearing section mounted for rotation on a respective drive shaft axis through the body and having an offset throw section, the piston and offset throw section of the drive shaft being connected such that reciprocating movement of the piston increases and decreases a size of the internal volume between minimum and maximum sizes;
- and
- a sleeve valve positioned in the cylinder and at least partially encircling the piston, the sleeve valve comprising a sleeve portion and a lip disposed at an end surface, the lip comprising an inner surface directed inward toward the internal volume and an outer surface directed away from the internal volume, the sleeve valve being movable in an axial direction between a first position where the port is open and a second position where the sleeve valve closes the port, the sleeve valve closing the port in the second position by at least part of the outer surface of the lip contacting a valve seat, the inner surface experiencing a positive pressure differential relative to the outer surface of the lip when gases within the internal volume are compressed by movement of the piston, the positive pressure differential applying an additional force in the axial direction toward the second position that assists in closing the port.
3 more elements
An internal combustion engine, comprising:
- a body defining first and second cylinders in communication with each other;
- a first piston in a first cylinder formed within the body and a second piston in a second cylinder formed within the body, the first cylinder and the second cylinder being disposed in an opposed arrangement such that an internal volume within the first cylinder and the second cylinder increases as the first and second pistons move away from each other and decreases as the first and second pistons move toward each other;
- a first port in the body to allow air and fuel into the internal volume;
- a second port in the body to allow exhaust gas out of the internal volume;
- a first sleeve valve positioned in the first cylinder and at least partially encircling the first piston, the first sleeve valve comprising a sleeve portion and a lip disposed at an end surface, the lip comprising an inner surface directed inward toward the internal volume and an outer surface directed away from the internal volume, the first sleeve valve being movable in an axial direction between a first position where the first port is open and a second position where the first sleeve valve closes the first port, the inner surface experiencing a positive pressure differential relative to the outer surface of the lip when gases within the internal volume are compressed by movement of the cylinder, the positive pressure differential applying an additional force in the axial direction toward the second position that assists in closing the first port;
- and
- a second sleeve valve positioned in the second cylinder and at least partially encircling the second piston, the second sleeve valve being movable in the axial direction between a first position where the second port is open and a second position where the second sleeve valve closes the second port.
4 more elements
In an internal combustion engine comprising a body, a piston moving within a cylinder formed within the body, and a port in the body to allow air and fuel into an internal volume within the cylinder, a sleeve valve positioned within the cylinder, the sleeve valve comprising:
- a sleeve body having a sleeve portion and an end surface, the sleeve body being slidably movable in an axial direction within the cylinder between a first position where the port is open and a second position where the sleeve valve closes the port;
- and
- a lip extending from the end surface and comprising an inner surface directed inward toward the internal volume and an outer surface directed away from the internal volume, the inner surface experiencing a positive pressure differential relative to the outer surface of the lip when gases within the internal volume are compressed by movement of the piston, the positive pressure differential applying an additional force in the axial direction toward the second position that assists in closing the port.
A method comprising:
- reciprocally moving a piston disposed in a cylinder formed within an engine body such that an internal volume within the cylinder increases and decreases between minimum and maximum sizes;
- admitting fuel and air into the internal volume via a port in the engine body;
- and
- moving a sleeve valve positioned in the cylinder and at least partially encircling the piston in an axial direction between a first position where the port is open and a second position where the sleeve valve closes the port, the sleeve valve comprising a sleeve portion and a lip disposed at an end surface, the lip comprising an inner surface directed inward toward the internal volume and an outer surface directed away from the internal volume, the inner surface experiencing a positive pressure differential relative to the outer surface of the lip when gases within the internal volume are compressed by movement of the piston, the positive pressure differential applying an additional force in the axial direction toward the second position that assists in closing the port.
1 more element
Dependencies are inferred from the claim text.