Not Applicable
Not Applicable
This invention relates generally to the field of internal combustion engines and more specifically to an internal combustion engine machine incorporating significant improvements in power, efficiency and emissions control.
This invention was conceived in response to the need for greater simplicity, efficiency and power in internal combustion piston engine designs.
Although two-stroke cycle engine technology has many advantages, it has deficiencies have caused widespread legislative restriction on its use and, in the US, an outright EPA ban on it by the year 2006.
Additionally, in nations where sophistication of publicly available technology is low, the prevalent two-cycle technology is producing high levels of air pollution and creating excessive fuel and lubricating oil expense due to the fact that the lubricating oil is burned along with the fuel in inefficient combustion. However, it is the only technology that the users can afford to acquire and maintain. This invention was conceived to defeat these problems.
Prior internal combustion piston engine technology has been divided into two primary groups, two-stroke cycle engines and four-stroke cycle engines. Prior two-stroke cycle engine technology has a number of advantages over four-stroke cycle technology. These advantages are a higher power to weight ratio and greater design simplicity that results in low production and maintenance costs. Four-stroke technology, on the other hand retained advantages over two-stroke technology in efficiency, dependability, and clean operation. No prior technology produced the advantages of both types in one engine.
Two Stroke Engine Technology Prior Art in General
Prior two-stroke cycle engines suffer a number of deficiencies. They are inefficient, up to or beyond ten times less efficient than comparable four-stroke cycle engines. They also inconveniently require that oil be measured and mixed with their fuel. As a result, prior two-stroke cycle engines operate much less cleanly than comparable four-stroke cycle engines, produce several times the volume of toxic emissions over that of comparable four-stroke cycle engines, experience a high incidence of plug fouling, are notoriously undependable, and use excessive fuel and lubricant.
Previous attempts at improved two-stroke technology have included linier engine configurations with pistons in each piston pair located diametrically opposite one another, as does this invention. One such popular configuration is popularly known as the “Bourke” engine. However, such previous linier designs have had a comparably narrow range of RPM speeds within which they could perform. These speeds are unsatisfactory for many applications and also complicate engine performance and design parameters for the various internal components.
Prevalent conventional engine technology causes wear on the many moving machine parts, largely due to components of articulated motion. This wear is concentrated, in particular, on the pistons, piston rings, cylinders, wrist pins, connecting rod bearings; main bearings and other related principal parts.
In present conventional engine technology, high operating temperatures bring increased complexity and expense in engine design and choice of materials.
Present conventional technology is not adaptable to attain significant energy savings by being run on fewer than all cylinders, when full power is not required, letting the unused cylinders and pistons disconnect from the drive train and come to complete rest until again needed.
Cylinder Head Exhaust Valve Prior Art
A number of cam or hydraulically controlled cylinder head exhaust valves are taught in prior two-stroke technology, but none were found teaching cylinder head exhaust valves applied to spark ignited two-stroke technology. However, spark ignition is the more compatible, and therefore overwhelmingly more dominant, configuration for lightweight engines. Therefore, this new use of a cylinder head exhaust valve in application to spark ignited two-stroke technology with the resultant increase in efficiency and reduction in toxic emissions is a much-needed improvement.
U.S. Pat. No. 2,097,883 to Johansson teaches an exhaust valve for two-stroke cycle diesel engines (i.e., not spark ignited). The valve in that patent is specifically designed to control combustion chamber pressure in compression ignition engines.
Oil Hoarding Rings Prior Art
No use of rings on a piston for the purpose of sealing the lubricated space and retaining oil between them has been found in prior technology. In fact, U.S. Pat. No. 4,364,307 teaches against such usage, particularly noting that it would be inappropriate to place sealing rings both above and below a lubrication groove. That, however, is precisely one design characteristic of this invention. Dynamic Pressure Pump, Double-Acting Piston Rod and Multi-Function Pistons to Carry, Distribute, and Recover Lubrication Oil A number of patents teach the transport of lubrication oil via a piston rod and/or pistons adapted to distribute oil transported by such a rod. Some use dynamic energy to propel the oil. (The general principle of dynamic energy/pressure pumps is to apply dynamic energy to the medium, such as oil, by scooping it up and propelling it by rapid cyclical motion.) However, none of said patents provide for complete “round trip” oil circulation via this method. They transport oil only one-way. This necessarily limits utility of the oil in cooling the engine, for it must either be slowly metered out so as to prevent a significant amount of it burning with the normal engine combustion, or it must be restricted from the cylinder interior entirely.
Further, dynamical propulsion oil pumps and oil carrying piston rod systems consistently teach their use only in lubricating the piston wrist pins, or lubricating/cooling the bottoms of the pistons. None are designed, as this patent teaches, to provide the primary lubrication to cylinder walls plus a return route for the oil for complete circulation loops. Examples include U.S. Pat. Nos. 2,569,103 and 2,645,213 (to Huber), U.S. Pat. Nos. 4,466,387, 4,502,421, and 4,515,110 (Perry), U.S. Pat. No. 2,865,349 (MacDonald), U.S. Pat. No. 3,633,468 (Burck), U.S. Pat. No. 3,992,980 (Ryan et al), and U.S. Pat. No. 3,930,472 (Athenstaedt), and U.S. Pat. No. 2,899,016 (Swayze).
Additional examples of systems incorporating piston rod oil transport also include pressure sealed walls at the base of their cylinders, as does this patent application. (These sealed walls are also known as “cross heads.”) However, as in those described above, none provide for complete oil circulation cycles to include oil return from the engine cylinder to the sump. Examples of these include U.S. Pat. No. 1,268,056 (Ruether), U.S. Pat. No. 1,827,661 (Kowarick), U.S. Pat. No. 2,064,913 (Hedges), U.S. Pat. No. 2,244,706 (Irving) and U.S. Pat. No. 3,710,767 (Smith).
An object of the invention is to provide an improved two-cycle reciprocating internal combustion engine that eliminates the previous disadvantages of two cycle technology as compared to four cycle technology, in that this engine produces higher efficiency, decreased toxic emissions, less fouling, and greater dependability while retaining the advantages of simplicity of production and of maintenance, and high power per unit weight.
Still yet another object of the invention is to provide an improved reciprocating internal combustion engine wherein, it is possible to increase the power or torque to weight ratio up to 100 percent or more over that of four-cycle technology without increasing the bore and stroke, compression ratio, or number of cylinders, while at the same time retaining a wide available range of RPMs, particularly including the most desirable or recommended operating engine speeds with special consideration given to friction heat and reciprocal motion, and thereby maintaining the most desirable aspiration conditions and reciprocating valve performance characteristics, resulting in a more efficient fuel consumption rate, over previous conventional or linier two-cycle engines.
Another object of the invention is to provide two-cycle engine that, unlike two cycle engines under previous technology, is not subject to the inconvenient necessity of mixing lubricating oil with the fuel in the same tank, nor in the combustion chamber.
A further object of the invention is to provide a two-stroke cycle internal combustion engine in which the lubricant circulates and is re-used independently from the fuel, thus using less lubricant.
Another object of the invention is to provide a two-cycle engine that, unlike two cycle engines under previous technology, is not subject to the extremely high pollutant emissions that result from the necessity of mixing lubricating oil with the fuel in the combustion chamber.
Still yet another object of the invention is to provide a two cycle engine that, unlike two cycle engines under previous technology, is not subject to the undependability and frequent spark plug fouling that results from the necessity of mixing lubricating oil with the fuel in the combustion chamber.
Another object of the invention is to provide a simple, compact engine structure that is, aside from the drive train, essentially symmetrical wherein oppositely disposed parts are substantially identical.
Yet another object of the invention is to provide an internal combustion engine that is simple and inexpensive to build and maintain.
Another object of the invention is to provide an improved reciprocating internal combustion engine wherein the wear caused by friction on piston, piston rings, cylinders, wrist pins, connecting rod bearings; main bearings another principal parts of the engine is significantly reduced below that of in conventional two-cycle or four-cycle engines having the same bore, stroke, compression ratio and number of cylinders through virtually eliminating piston side loads and the resultant piston and cylinder wear.
Yet another object of the invention is to produce an improved reciprocating internal combustion engine wherein each cylinder can produce one combustion stroke with each revolution of the crankshaft. This amounts to two power strokes for each piston pair for each shaft revolution and a power stroke for each movement of the piston rod.
Another object of the invention is to produce an improved reciprocating internal combustion engine wherein the piston rod travel between combustion strokes is 50 percent less than in present conventional two-cycle technology engines of the same bore and stroke, compression ratio, and number of cylinders, thus saving energy wasted in previous technology and saving commensurate fuel.
A further object of the invention is to provide an improved internal combustion reciprocating engine that runs significantly cooler than those of present technology, thus reducing corrosion and wear and making choice of applicable construction materials broader and less expensive. The improved cooling is derived from the increased lubricating/cooling oil flow provided and also from expansion cooling of the exhaust gases.
Another object of the invention is to provide an improved reciprocating internal combustion engine having increased life expectancy by reducing the need for the engine to labor excessively or to be operated in an R.P.M. speed range that is beyond the design capability originally intended or recommended in order to fulfill the requirements for torque and/or horsepower.
Another object of the invention is to provide a linear two-stroke cycle internal combustion engine that operates smoothly and efficiently over a wide range of rpm speeds.
Still yet another object of the invention is to provide an improved reciprocating internal combustion engine that is particularly adaptable to being run on fewer than all cylinders when full power is not required, letting unused banks of cylinders and pistons disconnect from the drive train and come to complete rest until again needed, thus saving energy and also ensuring that the load on each end of the piston rod remains substantially equal in that for any given fuel setting the force of the explosion is the same, that is, the unit force exerted upon the opposite ends of the piston rod by successive explosions is equal, even when a pair of pistons is put in “resting” mode.
A further object of the invention is to provide an internal combustion engine that can operate using a wide range of fuels to include alcohol, gasoline, diesel, and others.
Still yet another object of the invention is to provide an internal combustion engine that is easily adapted for glow plug, spark ignition or compression ignition.
Another object of the invention is to provide improved reciprocating internal combustion engine technology compatible to both two-cycle and four-cycle technology of increased simplicity over each or these present technologies.
Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, three embodiments of the present invention are disclosed.
In accordance with preferred embodiments of the invention, there is disclosed a reciprocating internal combustion engine machine incorporating significant improvements in power, efficiency and emissions control, primarily by eliminating the mix lubricating oil with the engine fuel and segregating the lubricating oil and fuel at all times.
The drawings constitute a part of this specification and include exemplary modes of the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
a is an expanded top view of the center section of the multi-function “pop-top” piston illustrated in
a
The key novelties of this invention lie in its means of lubrication combined with its means of aspiration and exhaust. A number of alternative modes are offered and they can be “mixed and matched” as needs dictate. Note that in every mode described, fuel injection may be substituted for carburetion, providing increased performance, but at the expense of increased system complexity and monetary cost.
Referring to
On either end of the combination oil sump/crankcase is a cylinder (103) with a sidewall (103a), cylinder head (104), exhaust assembly block (105) exhaust cam block (106) having an exhaust port to atmosphere (107), an air or air/fuel transfer cover (115) and an exhaust cam passive sprocket (108). On each cylinder head is also mounted an air/fuel transfer passage cover and a spark plug (113) with spark plug wire (114) attached.
Extending from the facing side wall of the oil sump/crankcase is an output drive shaft (112), a shaft with exhaust cam power sprockets (109) linked to exhaust cam passive sprockets (108) by two exhaust cam drive belts (110), tensioned by an exhaust cam drive belt tensioning pulley (111).
Referring to
Referring to
Keys to this invention are the features that allow engine oil and fuel to remain separate throughout the combustion process. Prior conventional two-cycle engine designs required lubricating oil to be measured and mixed with their fuel. This caused the engines to “burn dirty,” producing prodigious levels of toxic emissions, low efficiency, and poor dependability due to constant plug and system fouling. This invention overcomes such problems by incorporating improved aspiration systems and oil circulation systems that allow lubrication while segregating the lubricant from fuel and combustion.
One preferred mode, employing (as all preferred modes do) a dynamic pressure lubrication pump system, is illustrated in
In this configuration, oil (301) is picked up by nozzles (302a) of pick-up pipes (302) extending from the piston rod (304) into the crank case/sump (101). These nozzles are thrust to and fro in a reciprocating manner through the sump oil (301) due to the motion of the piston rod (304) to which they are attached. On each thrust, oil is forced into one or the other nozzle by dynamic pressure. The nozzles may be flared in order to increase the dynamic pressure applied. Oil passes through the nozzle, enters the sump oil pick-up pipe (302), via which it then travels to the multi-function piston (308) where it exits via the piston oil inlet ports (308a) and circulates about the multi-function piston (308) between the oil hoarding rings (308c) that prevent the oil (301) from coming in contact with combustion fuel and air or combustion products above or below the multi-function piston (308). As it circulates, continued static pressure from additional oil feed, plus dynamic pressure caused by reciprocating piston rod motion causes the oil to re-enter the multi-function piston (308) through the piston outlet ports (308b) from whence it travels back down the piston rod (304) via an oil return outlet pipe (303) to drip through the piston rod sump outlet (303a) back into the crank case/sump (101) where it cools. Thus, lubricating oil circulation is completed without the oil ever coming into contact with combustion fuel or air.
The oil (301) rests in the sump (101) where its cooling is promoted through stirring by motion of the sump oil pick-up pipe (302) until it again enters the circulation system.
This diagram illustrates means by which engine performance is further enhanced through the addition of an exhaust valve (311) in each cylinder head (104). Note that each cylinder (103) has an intake port (317d) that resembles and functions in much the same manner those in present popular two-cycle engines. However, the exhaust valve (311) in the cylinder head (104) replaces the standard prior technology exhaust port on the cylinder side-wall. Action of this valve may be independently adjusted in such a way as to obtain maximum scavenging effect, best combustion and best compression time and pressure, allowing the engine to burn more cleanly and making the engine more readily compatible with a wider range of fuels than in previous conventional technology.
Further detailed in
A piston rod (304) is linked by a push rod (305) to a crank plate (306) that turns a cam drive shaft (306a) and meshes with an output shaft cog (307) driving an output drive shaft (112). Oil (301) contained in the oil sump/crank case splashes as the various contained components move, thus ensuring complete lubrication of all parts encased therein.
Connected to each end of the piston rod is a multi-function piston (308) having piston oil inlet ports (308a), piston oil outlet ports (308b), oil hoarding rings (308c), a piston head (308d), and a piston base (308e).
Each cylinder (103) has a head (104) with an exhaust valve (311), exhaust valve stem (312), exhaust valve stem ball (313), exhaust valve spring (314), and exhaust valve cam (315), exhaust ports to atmosphere (107), and spark plugs (113).
Each cylinder has a combustion chamber (316), a compression chamber (317), compression chamber air or air/fuel inlet port (317a), compression chamber air or air/fuel inlet port one way reed valve (317b), compression chamber air or air/fuel outlet port (317c), combustion chamber air or air/fuel inlet port (317d), an air or air/fuel transfer passage (309) leading from the compression chamber to the combustion chamber including an air/fuel transfer passage cover (115). At the base of each cylinder is a pressure seal (318) in the oil sump/crankcase combination end walls and cylinder compression walls (101b), through which the piston rod (304) passes.
Now referring to
Turning to
Referring to
This system includes a piston (950), air or air/fuel ports (906), a piston rod (911), piston oil supply port (907), piston oil return port (908), air or air fuel intake valve head (900), valve seat (901), valve stem (902), valve spring (903), valve spring collar (903a), valve guide (904). The system also includes a valve rod (902a) and a control peg (902b).
Detailed is a multi-function piston configured for the third preferred mode. In this mode, an air or air/fuel mixture intake valve head (900) and intake ports (905) are actually located each the piston head. By substituting these valves and ports fixed intake ports in the cylinder side-wall (103a), increased control over air/fuel aspiration becomes possible. In this figure, the piston intake valve head (900) is open. Note that the valve stem (902) extends into the piston head and the valve head (900) fits snuggle in the seats in the piston head valve seat (901).
The intake valve head (900) is pushed open by a valve rod (902a) one end of which is in attached to a stem (902) of the given valve (900) and the other end of which impinges upon a control peg (902b) that prevents the valve rod (902a) from traveling with the piston rod (911) for its full stroke. When the piston (950) and piston rod (911) begin their power stroke, the valve rod (902a) travels with them, pushed along by the valve stem (902), the inertia of the valve rod (902a) being overcome by the valve spring (903).
Before the piston rod (911) completes its power stroke, valve rod (902a) comes in contact with a control peg (902b). This control peg stops further travel of the valve rod (902a). Although the valve rod stops moving, the piston rod (911) continues traveling to the bottom of its power stroke, sliding past the now motionless valve rod (902a). As a result, one end of the now motionless valve rod pushes against the valve stem (902), compressing the valve spring (903) and forcing the valve head (900) open. Air or air/fuel mixture rushes through the opened valve, transiting through air or air/fuel ports (906) in the piston. Shortly thereafter, the piston rod (912) “bottoms out” finishing its power stroke, and reverses direction to start its compression stroke.
As the piston rod (911) begins its compression stroke, its motion slides the valve rod (902a) away from the control peg (902b) and allows the valve spring (903) to once again force the valve head (900) closed. As the piston (950) continues in its compression stroke, pressure above it in the combustion chamber furthers serves to keep the valve head (900) firmly seated and closed. The piston stroke continues through compression, combustion and exhaust and the cycle repeats.
Lubrication for each piston is accomplished through the dynamic pressure lubrication oil system previously described, with oil distribution accomplished via a piston oil supply port (907) and a piston oil return port (908). (Details of the lubrication system are not illustrated in order to preserve simplicity, but are essentially identical to the dynamic pressure system previously described.)
This mode provides increased control over the combustion process in that it allows independent control of the cylinder head exhaust valve and off the air or air/fuel intake valve. This control translates into cleaner, more efficient combustion and increased adaptability to a wide range of fuels. Although this mode offers significant performance benefits, it is also more complex to manufacture and maintain than the first and second preferred modes.
The piston is centered in its cylinder by the oil hoarding rings (1008) that also keep the lubrication oil from escaping above or below the piston. When the valve head (900) opens, air or fuel/ail mixture rushes up from the base of the piston (1010) through the air or air/fuel valve ports (905) past the valve seat (901) and out through the piston head (1009).
In
In addition to the features documented in these drawings, further benefits may be derived by incorporating different means of ignition, to include not only spark plugs, but, alternatively, glow plugs and/or explosive compression in the combustion chamber.
Additionally, alternate incorporation of various drive trains, substituting, for example, a rack and pinion, ratchet drive, or unidirectional or segmented gear arrangement in place of the crank plate system here described, may render the system lighter and more compact and may allow greater flexibility in choice of fuels by providing for a greater range of piston dwell times then in rotary transmission systems, thus promoting more complete and efficient fuel combustion. The engine may also significantly benefit from addition of an oil cooler and from a turbo-charger, super-charger, intake air compressor, fan, or blower. While the invention has been described in connection a preferred embodiments, it is not intended to limit the scope of the invention to the particular forms set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.
This application is based on provisional application Ser. No. 60/424,981, filed on Nov. 8, 2002.
Number | Name | Date | Kind |
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2825319 | Harrer | Mar 1958 | A |
6209495 | Warren | Apr 2001 | B1 |
Number | Date | Country | |
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20040099228 A1 | May 2004 | US |
Number | Date | Country | |
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60424981 | Nov 2002 | US |