Not Applicable.
1. Field of the Invention
This invention relates to a radial internal combustion engine.
2. Description of the Related Art
Radial engines are well known, and many attempts have been made to improve their ability to transfer the power of the exploding gas into mechanical power. The two major types of radial engines are the piston and the rotary engines. Although most radial engines are used for aircraft, many designs can be used in any application.
Various ways to improve the radial piston engine have been proposed. For example, U.S. Pat. No. 4,084,555 describes a slosh plate type design that is used to transfer engine power to the power take-off. However, this design does not offer high torque and places all of the power transfer to one small location on the plate. The engine in U.S. Pat. No. 4,194,404 uses a connecting rod for energy transfer but still places undo force on the piston and cylinder walls. The engine in U.S. Pat. No. 4,727,794 does reduce the piston friction, but a larger engine block and an offset to the piston rods are used which can increase vibration. The engine in U.S. Pat. No. 3,964,450 does reduce the friction by locking in the piston rod with thrust bearings. However, the design uses a moving vane to transfer energy. This design requires a larger outside diameter to transfer power to, and as a result, spark plugs and injectors may not be placed in the best place for low emissions. The engine in U.S. Pat. No. 5,003,935 is principally designed to reduce noise and does not necessary try to improve output performance. The engine in U.S. Pat. No. 5,803,041 is a design that uses vanes or flapper valves to transmit the energy depending where the engine is positioned but does not offer the power handling capability of a piston design. Other background patents include U.S. Pat. Nos. 5,682,843, 6,223,711, 6,318,067, 6,250,279, 6,349,696, 4,056,906, 735,035, 2,044,113, 2,419,305, 2,491,630, 2,618,253, 2,671,983, 3,308,797, 3,734,072, and foreign patents FR 675,425, GB 392,282, GB 1,149,988 and GB 4,101,476.
Thus, there is a continuing need for a radial piston engine wherein power take-off is truly balanced such that the piston runs truly parallel to the cylinder walls. There is also a need for a radial engine that provides improved gas mileage by reducing piston drag. There is also a need for a radial engine that produces greater torque.
The foregoing needs are met by a radial internal combustion engine according to the present invention. The engine includes an engine block having a plurality of combustion chambers radially arranged on the periphery of the engine block. Each combustion chamber is defined by a cylinder, a reciprocating piston contained within the cylinder, and a cylinder head on the periphery of the engine block. An exhaust port is associated with and in fluid communication with each combustion chamber. Each exhaust port includes an exhaust valve. An intake port is associated with and in fluid communication with each combustion chamber for directing intake air into its associated combustion chamber. Each intake port includes an intake valve. A fuel injector is associated with each intake port and its associated combustion chamber. Each fuel injector is positioned for directing fuel into intake air in its associated intake port or positioned for directing fuel into intake air in its associated combustion chamber to form an air-fuel mixture. A spark device is associated with each combustion chamber for igniting the air-fuel mixture in its associated combustion chamber. The engine includes an output shaft, and at least one flywheel secured to the output shaft. At least one rotating gear is connected to each piston, and at least one rotating gear for each piston engages a surface of at least one flywheel. The reciprocating motion of each piston causes rotation of each rotating gear that engages a surface of at least one flywheel thereby causing rotation of at least one flywheel and the output shaft.
It was found all of the radial engine piston designs in the prior art either put some pressure on the cylinder walls due to crankshaft design action, or need a thrust bearing to support the push on a moving plate or wheel. The radial engine of the present invention eliminates the need for both and allows for a piston to be supported by four gear wheels that distribute the power to two flywheels that connect all clockwise rotating gears. This allows the piston at all times to run parallel to the cylinder wall with little resistance.
The radial engine of the present invention can be made in any size diameter and can be paralleled with more of the same units. The engine can be made with any number of cylinders. Typically, when manufactured with less than three cylinders, the radial engine of the present invention uses a chain drive. One preferred design for the radial engine of the present invention has eight or more cylinders of even numbers and fires the cylinders 180 degrees to each other in unison. This allows the flywheel to pick up the power evenly from four gear wheels.
The piston and block components are important features of the radial engine of the present invention. The piston is a very light low mass unit where the power, rather then going to a piston rod, goes to two flanges that can be permanent parts of the piston. The flanges bend out and turn 180 degrees to put the power takeoff outside of the engine block. This design can take many forms, such as multiple parts doing the same function and having a single piston stem that comes from the center of the piston that has a flange assembly alike to the above mentioned. The flange on the piston can be any size robust enough to handle the power delivery. The gear wheels can also be made larger or smaller to accommodate the size and compression requirements of the piston.
The header on top of the cylinder of the radial engine of the present invention can be of a traditional design. If one wanted to add a standard valve construction it could be accomplished by placing a sinusoidal design to the outside of the flywheel so that the valve lever arm would ride on this curvature producing the required up and down motion needed for the valve actuation. However, designs incorporating electronic valves can eliminate camshaft, rods and chains.
The entire engine block is housed in a two part container that can hold oil. Both sides of the container can hold oil or other fluids. This container can have the mounting brackets necessary to hold the engine in place in a vehicle or plane. Standard methods can pump the oil to the cylinders and to the gears and respective bearings. Water can pass around each cylinder as in conventional engines, and water lines can come out the outside diameter surface of the engine block. Air cooling is also suitable. Intake and exhaust manifolds are used wherein two cylinders share an intake and the next two cylinders share an outtake (exhaust). Gas is piped below the engine, outside the flywheel and main engine housing. Any number of cylinders is possible. Single cylinders and two cylinder designs with chain power take-offs are also possible for lawnmowers and motorcycles.
The radial engine of the present invention eliminates a number of problems with all earlier engines and is easy to build with its parts simple to fabricate. The engine block would require less metal then a conventional engine block and is easy to mold or extrude. Since there is no crankshaft, its weight and machining are eliminated. Because of its flat design, the radial engine of the present invention can also offer a lower profile in modern cars lowering the hood and making it safer especially for accidents involving pedestrians.
It is therefore an advantage of the present invention to provide a radial internal combustion engine that dramatically reduces cylinder friction and wear thereby improving gas mileage and lowering emissions.
It is another advantage of the present invention to provide a radial internal combustion engine that reduces the weight of the engine by eliminating a crankshaft and using less block material required to hold the other components in place thereby offering a significant weight savings.
It is yet another advantage of the present invention to provide a radial internal combustion engine that has increased torque. With the method of transfer of power from the gear to the flywheel, there is a 3-6 to 1 ratio of transfer depending on the size of the gear wheel. This allows for numerous cylinder firings per single rotation of the flywheels.
It is still another advantage of the present invention to provide a radial internal combustion engine that allows for a low mass piston, which provides for higher speeds and greater horsepower.
It is yet another advantage of the present invention to provide a radial internal combustion engine that can be used for standard internal combustion engines, diesel and 2 cycle designs. It can also be used as a pump if the power is reversed.
It is still another advantage of the present invention to provide a radial internal combustion engine that can be used in a single or two-cylinder engine where the flywheel is replaced with a chain pickup. This chain has a center pickup shaft below the piston(s) where the chain would go over the counter clockwise rotation gears and positioned over two freewheeling sprockets that transfer the power to the main shaft.
These and other features, aspects, and advantages of the present invention will become better understood upon consideration of the following detailed description, drawings, and appended claims.