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US 4,996,953 AGranted
Two plus two stroke opposed piston heat engine
OwnerErik S. Buckinventor
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OwnerErik S. Buckinventor
Estimating the term…
Combustion engines have opposed pistons in one or more cylinders, with the piston motion determined by cams. Ports, for intake and exhaust, are at one end of the cylinder, opened or closed by one piston, with the combustion chamber at the other end, and the engine being well suited to the optional use of a combustion chamber separate from the cylinder and with the communicating passages controlled by the other piston. That arrangement makes the engine particularly suitable for using heavy or unconventional fuels. The cam profile provides for a four-stroke cycle; one piston moves during the intake and exhaust strokes, while the second piston moves for compression and power strokes. Thus the advantages of a four-stroke engine are obtained while retaining the simplicity of a two-stroke engine. The cam profile may be tailored to the burning characteristics of the fuel, as by providing a period of dwell between the end of the compression stroke and the beginning of the power stroke. The engine is well suited to the use of compression ignition, but spark ignition is feasible. The isolated combustion chamber may also be replaced by a heat exchanger, to use an external heat source.
An engine, comprising at least one cylinder, a pair of opposed pistons in said cylinder including a power piston and an intake piston and defining a variable space therebetween,
In a heat engine suitable for multiple fuel operation, having a cylinder, first and second opposed pistons in said cylinder including a power piston and an intake piston, and cam means interconnecting said pistons to convert axial movement of said pistons in said cylinder into rotary motion, the improvement comprising:
In an opposed piston engine including at least one cylinder and a pair of opposed pistons in said cylinder to compress a working gas and provide a power stroke with means for converting the movement of the pistons into useful rotary motion, the improvement comprising:
An improved cam-operated barrel type engine in which a plurality of generally axially extending cylinders are arranged in angularly spaced relation and each have pair of opposed pistons which are operated by drive cams common to all of said cylinders, the improvement comprising a separate external combustion chamber for each of said cylinders, port means connected each said chamber to its associated said cylinder, fuel inlet means for admitting fuel into the interior of each said chamber, said fuel inlet means effective to admit said fuel when the pressure in the associated said chamber is lower than the fuel pressure, and valve means for preventing fuel or vapor flow out of a said chamber and into a fuel supply line.
The method of operating a heat engine having a pair of opposed pistons in a common cylinder, in which said opposed pistons are caused to operate in a cycle of operation including at least an intake, a compression, a power and an exhaust stroke, and in which an external combustion chamber communicates with said cylinder through a port controlled by one of said pistons, comprising the steps of admitting fuel to be burned into said external chamber while said port is covered by said one piston, and causing gasses trapped between said pistons to be compressed and heated to a combustion temperature by relative movement of the other piston in the cylinder toward said first piston prior to the opening of said port by said first piston, and causing said first piston to open said port to admit the highly compressed and heated gasses into said chamber for combustion.
The method of operating a heat engine having a pair of opposed pistons in a common cylinder, in which said opposed pistons are caused to operate in a cycle of operation including at least a compression, a power and an exhaust and an intake stroke, and in which an external combustion chamber communicates with said cylinder through a port controlled by one of said pistons, comprising the steps of admitting fuel to be burned into said external chamber during said intake stroke, causing gasses trapped between said pistons to be compressed and heated to a combustion temperature by relative movement of the other piston in the cylinder toward said first piston during said compression stroke, and moving said first piston relative to said port during said compression stroke to admit compressed and heated gasses into said chamber for combustion, maintaining said port open during said power stroke.
The method of operating an opposed piston fuel burning engine in which a combustion cylinder has an opposed pair of pistons defining an intake piston and a power piston, in which the movements of the pistons are controlled by profiled cams, and the cylinder has intake and exhaust ports controlled the movement of the power piston and including a means for admitting fuel into the space between the pistons for combustion and expansion, comprising the steps of causing the intake piston to move in an intake stroke away from the power piston during the time that the power piston has uncovered an intake port and causing air to be drawn into the cylinder, causing the power piston to move toward the intake piston to close the intake and exhaust ports in a compression stroke, causing fuel to be admitted into the space between the pistons to form a fuel/air mixture in the cylinder for combustion, causing combustion of such mixture at or near the end of said compression stroke, causing said power piston to move away from said intake piston in a power stroke to open at least said exhaust port, and causing said intake piston to move toward said power piston to purge the space therebetween of burnt fuel gasses.
Dependencies are inferred from the claim text.