Abstract:
A single-cylinder, dual head internal combustion engine wherein in a single, mechanically unconstrained piston moves reciprocally within the cylinder between the two heads. Magnets or nonmagnetized ferromagnetic structures in the piston interact with magnets in a sleeve riding on the outside surface of the cylinder to cause synchronous movement of the sleeve. A yoke coupled to the sleeve may be coupled to a conventional crankshaft to convert the reciprocal movement of the sleeve into rotary motion. Multiple single-cylinder, dual head units may be ganged to form multi-cylinder engine configurations. In one embodiment, the magnets in the sleeve are electromagnets whereby de-energizing the electromagnets decouples the sleeve from the piston, thereby eliminating the need for a mechanical clutch in a power train driven by the engine.

Description:
RELATED APPLICATIONS 
     This is a Continuation-in-Part application of application Ser. No. 13/537,248 for SINGLE-CYLINDER, DUAL-HEAD INTERNAL COMBUSTION ENGINE HAVING MAGNETICALLY COUPLED POWER DELIVERY filed Jun. 29, 2012, that application being included herein in its entirety by reference. 
    
    
     FIELD OF THE INVENTION 
     The invention pertains to internal combustion engines and, more particularly, to single-cylinder, dual-head internal combustion engines having a single piston moving therein between the heads and wherein the mechanical power generated by the engine is magnetically coupled to an external load. 
     BACKGROUND OF THE INVENTION 
     Internal combustion engines are well known. Among the known internal combustion engines, there may be found single-cylinder, dual headed engines. In such engines, a single, dual-faced piston moves within a single-cylinder. A combustion chamber is located at each end of the cylinder, each combustion chamber typically having one or more inlet valves, one or more exhaust valves, and an ignition source (e.g., a spark plug. In these engines, a connecting rod attached to the piston is conventionally connected to a crankshaft and the power generated by the reciprocal motion of the piston is converted by the crankshaft into rotary motion. 
     Lubrication is provides by oil from the crankcase splashed into the cylinder by the connecting rod. 
     Intake and exhaust valves may be actuated by a cam shaft disposed at each end of the cylinder. 
     Such engines of the prior art may be either two-cycle or four cycle (or two-stroke or four-stroke in the vernacular). In a two-stroke engine, a complete combustion cycle is completed for each revolution of the crankshaft, in other words, for each up and down excursion of the piston. 
     In a four-stroke engine, a combustion cycle requires two revolutions of the crankshaft resulting in two complete up and down excursions of the piston for each combustion cycle. 
     Such conventional designs, whether two-stroke or four-stroke are typically both bulky and heavy. Two-stroke engines are typically more compact and lighter than four-stroke engines having the same rated power output. Consequently, two-stroke engine designs have found favor in applications such as motorcycles, marine engines, and in yard and garden tools. Extraction of mechanical power from a dual-head cylinder of internal combustion engine conventionally requires the piston to be connected to a connecting rod or another part that moves through an opening in one of the cylinder heads. This creates two difficult problems: (a) sealing of the head at this opening so that the seal would withstand high pressure of hot gas created in the combustion process while, at the same time, allowing the connecting rod to move through the sealed opening; and (b) prevention of an accelerated corrosion of the connecting rod and joints exposed to a very hot corrosive exhaust gas. To date, no practical solutions of these problems have been offered. These problems prevent usage of engines with dual-head cylinders in mechanically operated applications such as automobiles, motorcycles, compressors, pumps and garden tools. The present invention offers the way to extract mechanical power from dual-head cylinders while avoiding these problems. 
     DISCUSSION OF THE RELATED ART 
     U.S. Pat. No. 2,317,167 for INTERNAL COMBUSTION ENGINE issued Apr. 20, 1943 to Bernard M. Baer shows an engine having a cylinder with a head at each end. A single piston connected to a conventional crankshaft moves within the cylinder. Valves and a sparkplug are disposed at each end of the cylinder, the valves being actuated by a camshaft. A connecting rod is attached to one side of the piston. 
     U.S. Pat. No. 3,076,440 for FLUID COOLED DOUBLE ACTING PISTONS FOR HIGH TEMPERATURE ENGINES issued Feb. 5, 1963 to Henry M. Arnold teaches a double acting piston suited for actuation by highly super heated steam, the engine being cooled by circulating a cooling agent. 
     U.S. Pat. No. 5,816,202 for HIGH EFFICIENCY EXPLOSION ENGINE WITH DOUBLE ACTING PISTON issued Oct. 6, 1998 to Gianfranco Montresor discloses a single piston disposed between two explosion chambers wherein auxiliary pistons of a shaft coupled to the piston control the intake of gases to the combustion chamber. 
     U.S. Pat. No. 5,844,340 for RODLESS CYLINDER DEVICE issued Dec. 1, 1998 to Mitsuo Noda discloses free-moving piston in a cylinder activated by a working fluid. The piston is magnetically coupled with a unit that freely slides on the cylinder. The movement is used for the cylinder lubrication. Unlike in an internal combustion engine, no transfer of power from the free-moving outside unit to external load is mentioned. Neither is there any specific information regarding the magnets or magnetic coupling. 
     U.S. Pat. No. 7,296,544 for INTERNAL COMBUSTION ENGINE issued Nov. 20, 2007 to Georg Wilhelm Deeke provides a four-stroke internal combustion engine have a cylinder with a single, double acting piston therein. A conventional connecting rod is attached to one side of the piston. 
     U.S. Pat. No. 7,318,506 for FREE PISTON ENGINE WITH LINEAR POWER GENERATOR SYSTEM issued Jan. 15, 2008 to Vladimir Meic teaches a free moving piston reciprocating in a double-head cylinder. The structure is integrated into a linear power generator. No application as an integral combustion engine is taught and neither are moving parts outside the cylinder or magnetic coupling between any moving parts. 
     U.S. Pat. No. 7,438,028 for FOUR STROKE ENGINE WITH A FUEL SAVING SLEEVE issued Oct. 21, 2008 to Edward Lawrence Warren discloses a cylinder structure that includes a fuel saving sleeve having projections on one end. A magnetic force is used to keep the fuel saving sleeve at the top of the engine cylinder during the intake and compression strokes. This makes the sleeve act as an air displacer during the intake and compression strokes. The projection transfers the pressure of burning gases on the sleeve to the piston during the expansion stroke. 
     U.S. Pat. No. 7,721,685 for ROTARY CYLINDRICAL POWER DEVICE issued May 25, 2012 to Jeffrey Page discloses a cylindrical rotary power device that utilizes pairs of connected back-to-back cylinders and pistons, each with its own head. The transfer of power from the piston pairs is via a mechanical link to a crankshaft through an opening between the connected cylinders. No magnetic coupling between any parts of the device is taught or suggested. Neither are free-moving single pistons nor double head cylinders disclosed. Instead, there are pairs of connected back-to-back pistons and cylinders each with its own head. 
     German Patent No. DE3921581 (A1) for IC ENGINE WITH DOUBLE ACTING PISTON HAS PISTON—HAS ITS PISTON ROD ATTACHED TO CROSSHEAD issued Oct. 31, 1990 to Guezel Ahmet discloses a cylinder having dual combustion chambers and a single piston moving in the cylinder. A connecting rod passes through a seal in one of the heads. 
     None of these patents, taken singly, or in any combination are seen to teach or suggest the novel single-cylinder, dual head internal combustion engine of the present invention. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention there is provided a single-cylinder, dual head internal combustion engine wherein in a single, mechanically unconstrained piston moves reciprocally within the cylinder between the two heads. Magnets or ferromagnetic structures in the piston interact with magnets in a sleeve riding on the outside surface of the cylinder to cause synchronous movement of the sleeve. A yoke coupled to the sleeve may be coupled to a conventional crankshaft to convert the reciprocal movement of the sleeve into rotary motion. Multiple single-cylinder, dual head units may be ganged to form multi-cylinder engine configurations. 
     In one embodiment, the magnets in the sleeve are electromagnets whereby de-energizing the electromagnets decouples the sleeve from the piston, thereby eliminating the need for a mechanical clutch in a power train driven by the novel engine. 
     It is, therefore, an object of the invention to provide a single-cylinder, dual head internal combustion engine wherein all output power is provided by a sleeve magnetically coupled to the piston of the engine. 
     It is another object of the invention to provide a single-cylinder, dual head internal combustion engine wherein magnets or ferromagnetic structures are provided in the engine piston, magnetic structures are provided in the cylinder wall, and magnets are provides in an external sleeve to magnetically couple the sleeve to the piston. 
     It is a further object of the invention to provide a single-cylinder, dual head internal combustion engine wherein a connecting rod or yoke is attached between the sleeve and a crankshaft. 
     It is a still further object of the invention to provide a single-cylinder, dual head internal combustion engine wherein such multiple single-cylinder, dual head units may be ganged into multi-cylinder internal combustion engine. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein: 
         FIG. 1  is a side elevational, cross-sectional, schematic view of the cylinder of the internal combustion engine of the invention; 
         FIG. 2A  is an end elevational schematic representation of the cylinder and sleeve of the internal combustion of  FIG. 1 ; 
         FIG. 2B  is a side elevational, schematic view of the internal combustion engine of  FIG. 1  showing a first embodiment of a connecting rod arrangement; 
         FIG. 2C  is a top plan, schematic view of a connecting yoke arrangement suitable for use with the internal combustion engine of  FIG. 1 ; and 
         FIGS. 3A-3D  are schematic representations of the stages of the combustion cycle of the internal combustion engine of  FIG. 1 ; 
         FIG. 4  is an end elevational, cross-sectional, schematic view of the internal combustion engine of  FIG. 1  showing the embedded magnetic coupling and cooling components; 
         FIG. 5  is a top plan, schematic view of a pair of the engines of  FIG. 3C  joined into a two-cylinder internal combustion engine; 
         FIG. 6  is a simplified system block diagram of a control system suitable for use with the internal combustion engine of the invention; 
         FIGS. 7A and 7B  are side elevational, cross-sectional, and end elevational, schematic views, respectively of an engine configuration having all sensors on a single side of the cylinder; and 
         FIGS. 7C and 7D  are side elevational, cross-sectional, and end elevational, schematic views, respectively of an engine configuration having the sensors diametrically disposed on two sides of the cylinder. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention provides a single-cylinder, dual head internal combustion engine. A single piston runs in the cylinder, reciprocal piston motion being generated by alternating firing of the combustion chambers formed at each end of the cylinder. There is no connecting rod or any other mechanism coupled directly to the piston. Rather, the piston is magnetically coupled to a sleeve surrounding the cylinder such that the external sleeve moves synchronously with the piston. As discussed in detail hereinbelow, a connecting yoke or other mechanism may be connected between the sleeve and a conventional crankshaft arrangement. 
     Two-stroke engines typically have two important advantages over four-stroke engines as they are generally simpler and lighter than four-stroke engines. In addition, two-stroke engines typically producing more power for a given cylinder displacement. However, two-stroke engines have several disadvantages when compared to four-stroke engines. 
     First, two-stroke engines don&#39;t last nearly as long as four-stroke engines. The lack of a dedicated lubrication system means that the parts of a two-stroke engine typically wear a lot faster. 
     Operating costs may be higher as two-stroke oil is expensive, and typically about four ounces of such oil per gallon of gas is required. It has been estimated that a car using a two-stroke engine would burn about a gallon of two-stroke oil every 1,000 miles. 
     Two-stroke engines are less fuel efficient than four-stroke engines. 
     Finally, two-stroke engines are heavy polluters. So much, in fact, that it is likely that fewer and fewer two-stroke engines will be used in the future. The pollution comes from two sources. The first is the combustion of the oil. The oil makes all two-stroke engines smoky to some extent, and a badly worn two-stroke engine can emit huge clouds of oily smoke. The second reason is the scavenging process (i.e., cross flow during the intake and exhaust phases: each time a new charge of air/fuel is loaded into the combustion chamber, part of it leaks out through the exhaust port). That accounts for the sheen of oil often seen around any two-stroke boat motor. Any leaking hydrocarbons from the fresh fuel combined with any leaking oil are also harmful to the environment. 
     These disadvantages now dictate that two-stroke engines are used only in applications either where the engine is used infrequently and/or where a very high power-to-weight ratio is important. 
     The single-cylinder two-head internal combustion engine of the present invention might technically be viewed as a two-stroke engine because two up and down motions of the piston (i.e., two complete revolutions of the crankshaft), results in two full power cycles (i.e., intake, compression, ignition/combustion, and exhaust). In other words, one complete combustion cycle is completed for each revolution of the crankshaft the same as in two-stroke engines and unlike conventional four-stroke engines that require two revolutions of the crank shaft to complete a combustion cycle. This is possible because the novel design of the internal combustion engine has two separate combustion chambers within the single cylinder. Consequently, while the intake cycle is occurring in the first combustion chambers, the exhaust cycle is occurring simultaneously in the opposite combustion chamber. Likewise, while compression is occurring in the first combustion chamber, intake is occurring in the opposite combustion chamber, etc. Consequently, for each revolution of the crankshaft, all four steps (i.e., intake, compression, combustion, and exhaust) portions have occurred. Therefore, the novel design allows a power (i.e. combustion) cycle for each revolution of the crankshaft instead of a power cycle once every two revolutions of the crankshaft. Consequently, the engine of the proposed novel design has much higher power-to-displacement and power-to-weight ratios than a conventional four-stroke internal combustion engine while maintaining the well-known benefits thereof. The novel engine provides many of the benefits heretofore only found in two-stroke engines while eliminating the two-stroke engine shortcomings (i.e., low fuel efficiency, high pollution, and extensive wear). 
     Referring first to  FIG. 1 , there is shown a greatly simplified schematic diagram of a single-cylinder, dual head internal combustion engine in accordance with the invention, generally at reference number  100 . 
     A hollow cylinder  102  houses a piston  104  that may move back and forth therein as shown by arrow  106 . Piston  104  is shown with conventional piston rings  120 . 
     Heads  108   a ,  108   b  are disposed at opposite ends of cylinder  102 . Each head  108   a ,  108   b  contains a pair of valve ports  116   a ,  116   b ,  118   a ,  118   b , respectively with associated valves  112   a ,  112   b ,  114   a ,  114   b , all shown schematically. 
     It will be recognized by those of skill in the art that in conventional four-stroke engines, intake and exhaust valves are implemented as spring loaded structure sealing against valve seats in the engine&#39;s head. Rocker arms force the valves open when the arms are activated by push rods riding on a cam shaft. Such an arrangement is not possible for the present engine, because the camshaft would have to be driven by the sleeve that does not necessarily closely follows the piston (for instance, when the engine is started and under hard acceleration). Instead, the timing of valve operation shall be related to the position and speed of the piston. This can be accomplished by using electromagnetically actuated valves as described hereinbelow. 
     Referring now also to  FIG. 7A-7D , there are shown side elevational ( FIGS. 7A and 7C  and end elevational ( FIGS. 7B and 7D ) schematic representations of two embodiments of piston, cylinder, sleeve and two sets of sensors  176 ,  178  detecting position of the piston and the sleeve, respectively. Sensors  176 ,  178  may be magnetic proximity sensors or any other appropriate sensors of types believed to be well known to those of skill in the art. First, piston position sensors  176  are discussed. An array of such sensors  176  is installed in the cylinder  102  wall parallel to its axis. Each sensor  176  is installed in a special recess, not specifically identified, in the outer surface (i.e., facing the sleeve) of the piston  104 . The recesses do not penetrate the cylinder  104  wall all the way to the inner space, not specifically identified, of the cylinder  102 , (i.e., the inner surface of the cylinder  102  remains untouched). The bottom of each recess is as close to the inner surface of piston  104  as practically possible in order to ensure an accurate detection of the piston  104  position. The sleeve  122  has a grove above the array of the sensors in order to accommodate the wires, not shown, that connect the sensors to a controller  152  best seen in  FIG. 6 . 
     As the piston  104  approaches one of the sensors  176 , the sensor  176  generates a signal that is sent to the controller  152 . Based on the time passed between the signals from two adjacent sensors  176 , the controller  152  calculates the speed of the piston  104  and its position at any moment until the piston  104  reaches the next sensor  176  and then this process is repeated. Thus, the position and speed of piston  104  are known for every moment of its movement. Based on this information and other parameters the controller  152  generates properly timed signals to actuate the intake and exhaust valves  112   a ,  112   b ,  114   a ,  114   b.    
     The controller could readily generate timing signals for spark generation. The necessary sensor technology for generating input signals as well as controller circuitry are both believed to be well known to those of skill in the art and, consequently, neither is further discussed herein. 
     One style of electromagnetically actuated valve may be implemented as an electrically-actuated solenoid configured to open conventional spring loaded valves. 
     In another embodiment of electrically actuated type of valve is a rotary valve. A rotary solenoid, stepper motor or other such actuator is used to selectively uncover and cover a valve port  116   a ,  116   b ,  116   a ,  116   b  at an appropriate time. 
     Another possible implementation of an exhaust valve is as a pressure relief valve that opens when the exhaust gas in one of the combustion chamber reaches a predetermined pressure. A mechanism for delaying the closing of the valve may also be provided to avoid trapping exhaust gases in the cylinder when the pressure actuated valve suddenly closes as soon as the pressure drops below the valve activation level. 
     It is envisioned that hybrid valve actuation systems combining two or more of the disclosed valve actuation technologies may be both useful and readily implementable. 
     Spark plugs  110   a ,  110   b  are disposed in respective heads  108   a ,  108   b . An electrical system including a timing mechanism may be used to provide a high voltage current to fire sparkplugs  110   a ,  110   b.    
     In alternate embodiments of the novel engine of the invention, a magneto mechanism such as those used in some two-stroke engines may be used to provide the high voltage for firing sparkplugs  110   a ,  110   b . Such ignition systems are believed to be well known to those of skill in the internal combustion engine art. Consequently, the ignition system required to make internal combustion engine  100  functional is not further discussed or described herein. 
     A sleeve  122  of slightly larger diameter than an external diameter of cylinder  102  shown disposed concentrically around cylinder  102 . However, for reasons of clarity, no magnetic coupling elements are shown in  FIG. 1 . The magnetic coupling elements are shown in  FIG. 4  and are described in detail hereinbelow. Sleeve  122  is free to slide reciprocally along an outer surface of cylinder  102 . 
     Referring now also to  FIG. 2A , there is shown an end-elevational schematic view of engine  100  of  FIG. 1  showing the relationship of sleeve  122  to cylinder  102 . Yoke connecting points  124  are diametrically disposed on sleeve  122 . 
     Referring now also to  FIG. 2B , there is shown a side elevational, schematic view of engine  100  but with a pair of connecting rods  128  (only one visible in FIG.  2 B), each having a proximal end, not specifically identified, rotatively attached to sleeve  122  via yoke connecting point  124  and an intervening bearing  126 . A distal end of each connecting rod  128  is connected to a crankshaft  132  through crankshaft bearings  130 . 
     Referring now also to  FIG. 2C , there is shown an alternate embodiment of a mechanism for connecting sleeve  122  with crankshaft  132 . Yoke  144  has a U-shaped portion that straddles sleeve  122 . The proximal ends of both sides of the U-shaped portion are connected to respective ones of yoke connecting points  124  through yoke to sleeve bearing  126 . A distal end of yoke  144  is connected to crankshaft  132  through crankshaft bearing  130 . 
     In conventional engines, lubrication is provided by oil “splashed” onto the cylinder wall from the crankcase by the connecting rods. In the novel engine  100  of the invention, an alternate way of providing cylinder lubrication must be provided. One way is to directly inject oil into the cylinder through one or more injection ports. A second alternative is to mix oil with the fuel (i.e. gasoline) as is common practice in two-stroke engines. While either injecting oil or adding oil to the fuel could probably supply adequate lubrication, direct oil injection would probably be more effective as less oil would be in the mixture and more directly deposited onto the surfaces. 
     However, friction and thus the amount of required lubricant may be reduced by forming cylinder  102  from a ceramic material, especially a “self-lubricating” ceramic composite. Such ceramic composites include, for example, an Alumina-graphite composite, a Silicon nitride-graphite composite, or an Alumina-CaF 2  composite. These composites can withstand high operating temperatures (e.g., 750-1750° F. (400-950° C.)). Other such materials may be known to other persons of skill in the art and the invention is not considered limited to the ceramic materials chosen for purposes of disclosure. Rather, the invention is intended to include any other suitable ceramic materials in addition to those chosen for purposes of disclosure. 
     Ceramics inherently less prone to mechanical wear, then metals. In addition, the solid lubricant components in the composites (graphite, CaF2, etc.) greatly reduce the friction. These materials can be used for fabricating piston  104  and/or cylinder  102  or for coating the surface of one or both thereof. 
     In addition to cylinder wall lubrication, lubrication must also be provided for sleeve  122  as is slides on an exterior surface of cylinder  102 . It is believed that implementing the requisite lubrications system is well within the capabilities of a person of average skill in the art. Consequently, lubrication systems are not further discussed herein. 
     It will be recognized that additional mechanisms are required, at a minimum for example, one or more valve actuation mechanisms, intake and exhaust manifolds, a fuel source as well as a timed spark source to make a functioning internal combustion engine. 
     Referring now also to  FIGS. 3A-3D , there are shown progressive schematic diagrams illustrating the combustion cycle of the engine  100 . For simplicity and diagram clarity, reference numbers are not generally shown on  FIGS. 3B-3D . 
     In  FIG. 3A , the piston  104  is moving in a downward direction, exhausting spent gas  202  from the lower combustion chamber through exhaust valve  114   b . Simultaneously, fresh air/fuel mixture  204  is being brought into the upper combustion chamber through intake valve  112   a.    
     In  FIG. 3B , both exhaust valve  114   b  and intake valve  112   a  are closed, Piston  104  is moving upward thereby compressing the air/fuel mixture in the upper combustion chamber while drawing air/fuel mixture  204  into the lower combustion chamber through intake valve  112   b.    
     In  FIG. 3C , intake valve  114   b  is now closed and the compressed air/fuel mixture in the upper combustion chamber is ignited by spark plug  110   a . The resulting explosion forces piston  104  downward, thereby compressing the air/fuels mixture in the lower combustion chamber. 
     In  FIG. 3D , the piston  104  is again moving upward responsive to the ignition of the compressed air/fuel mixture in the lower combustion chamber. The movement of the piston thereby exhausts the contents of the upper combustion chamber through open exhaust valve  114   a.    
     This sequence is then repeated. 
     Referring now also to  FIG. 4 , there is shown an end elevational, cross-sectional, schematic view of the cylinder and sleeve of engine  100 . One of the novel features of internal combustion engine  100  is the unique arrangement of magnets and ferromagnetic structures (e.g.,  140 ,  136 ,  138 ) that couple sleeve  122  to piston  104 . 
     In  FIG. 4 , piston  104  is shown having magnets  140  embedded therein. The magnets are polarized radially, (i.e., in the direction perpendicular to the axis of the piston). The magnets are embedded in such a way that surface of one of the poles of each magnets is, preferably, exposed and flash with the side surface of the piston. Similarly, in case of nonmagnetized ferromagnetic structures, one surface of each structure shall be, preferably, exposed and flash with the side surface of the piston. This reduces the magnetic gap between the piston and sleeve thus increasing the strength of the magnetic coupling between the piston and sleeve. The piston magnets or ferromagnetic structures do not touch each other and are separated from each other by a nonmagnetic material the piston is made of. The magnets or ferromagnetic structures may be distributed over either the entire side surface of the piston or just a part of it, depending on the required strength of the magnetic coupling between the piston and sleeve and other factors. 
     Magnets  140  may be rare earth magnets, ceramic magnets, or other high-strength magnets know to those of skill in the magnetic arts. As Piston  104  will typically operate at a high temperature, magnets  140  need to be designed to operate at such temperatures without losing any significant portion of their magnetism. Ultra high temperature magnets are believed to be well known. For example, in the 1970s, Samarium Cobalt magnets were first formulated. These SmCo5 and Sm2Co17 magnets may be used at temperatures in excess of 300° C. “In about 1995, Electron Energy Corporation (EEC) began developing a new class of Sm2Co17 magnets for use at even higher temperatures. As a result, the following materials were developed: EEC24-T400, EEC20-T500 and EEC16-T550 for use at temperatures of up to 400, 500 and 550° C., respectively. It is believed that such magnets are suitable for the application. As other ultra high temperature magnets may be known to those of skill in the art, any other such suitable magnets may be used to replace the Samarium Cobalt magnets chosen for purposes of disclosure. Consequently, the invention is intended to include other suitable magnets in addition to the disclosed Samarium Cobalt magnets. 
     In still other embodiments, magnets  140  may be replaced with pieces of non-magnetized ferromagnetic materials. Such material may include but are not considered limited to soft iron, MuMmetal®, or other such materials. The use of non-magnetized ferromagnetic materials overcomes the possibility of magnets  140 , even when made from ultrahigh temperature magnetic material (e.g., SmCo5 or Sm2Co17) from demagnetizing over time from exposure to the high temperatures experiences in piston  102 . 
     Cylinder  102  and piston  104  are typically formed from a non-ferromagnetic material, for example, Aluminum, an Aluminum alloy, or ceramic, such as Alumina (Al 2 O 3 ), or any other suitable high-temperature ceramic, including “self-lubricating” types. Because cylinder  120  must have significant strength and stiffness to perform its intended function, it is anticipated that it must be designed with a relatively thick wall. “Thick walls could significantly reduce the strength of the magnetic coupling between piston  104  and sleeve  122 . To overcome the magnetic gap created by the wall thickness of the cylinder  102  wall, ferromagnetic structures  136  or nonmagnetized structures, not specifically identified, may be embedded within the wall of cylinder  102 . Surfaces of these ferromagnetic structures that face the space between the piston  104  and cylinder  102  and surfaces that face the space between the cylinder  102  and sleeve  122 , are, preferably, exposed and flush with the cylinder  102  surfaces in order to minimize the gap between the ferromagnetic structures  136  of the cylinder  102  and the magnetic elements,  140 ,  138  of the piston  104  and sleeve  122 , respectively. This arrangement ensures a maximal possible strength of the magnetic coupling between the piston  102  and sleeve  122 . The ferromagnetic structures do not touch each other and are separated from each other by the nonmagnetic material of which cylinder  102  is made. Ferromagnetic structures  136  are typically formed from a highly magnetically conductive material such as iron, Permalloy or Mu Metal® (also known as mumetal, MuMETAL, etc). The trademark on the term Permalloy has now expired. Mu Metal is the trademark of Magnetic Shield Corporation of Bensenville, Ill., USA. These materials are typically alloys of nickel and iron. Usually other elements such as copper, chromium and/or molybdenum are also found in such alloys. These materials are notable for their high magnetic permeability. 
     These ferromagnetic structures  136  convey magnetic flux between magnets or electromagnets  138  embedded in sleeve  122  and magnets or ferromagnetic structures  140  embedded in piston  104 . The sleeve magnets are polarized radially and the cores of electromagnets are oriented radially, (i.e., in the direction, perpendicular to the axis of the sleeve) The surfaces of the magnets and of the cores of electromagnets that face the cylinder are, preferably, exposed and flash with the inner surface of the sleeve. This arrangement ensures a maximal strength of the magnetic coupling between the magnets in the sleeve and magnets or ferromagnetic structures in the piston. The sleeve magnets do not touch each other and are separated by the nonmagnetic material from which sleeve is made. 
     The magnetic attraction between sleeve magnets or electromagnets  138  and the piston magnets or ferromagnetic structures  140  couple piston  104  to sleeve  122  so that sleeve moves reciprocally along the outer surface of cylinder  102  synchronously with piston  104 . Implementing magnets  138  as electromagnets may be useful to create a strong enough magnetic attraction to ensure that sleeve  122  remains coupled to piston  104  even when engine  100  is under load. As the movement of sleeve  122  is relatively small, providing power to electromagnets  138  using a flexible cable, not shown, connecting electromagnets  138  to an external power source, not shown is believed to be easily implementable. In other embodiments, sliding electrical contacts may be used to provide electrical power to electromagnets  138 . Other ways of providing power to electromagnets  138  will be known to persons of skill in the art. Consequently, the invention is not considered limited to any particular method or mechanism for connecting electromagnets  138  to a power source. Rather, the invention is intended to include any method or mechanism for providing power to electromagnets  138 . 
     By using electromagnets  138  in the sleeve  122  it is possible to switch on and off the magnetic attraction between the sleeve  122  and piston  104 . The ability to do so is important, since the attraction between the piston  104  and the sleeve  122  is needed only when all three of the following conditions exist:
         (a) the piston  104  and sleeve  122  move in the same direction;   (b) the piston  104  is slightly ahead of the sleeve  122 ; and   (c) the piston  104  is performing a power stroke (i.e. pushed by the pressure of the ignited fuel/air mixture  204 ).       

     Since the sleeve  122  does not always closely follow the piston  104  (for instance, when the engine  100  is started and/or when under hard acceleration), the relative position of the piston  104  and sleeve  122  and their speeds must be constantly monitored and processed by the controller  152 , best seen in  FIG. 6 , to verify existence of the aforementioned three conditions. When such conditions happen, the controller  152  sends a signal to activate the sleeve electromagnets  138 , (i.e., the controller  152  switches on the magnetic attraction between the piston  104  and sleeve  122 ). As soon as at least one of these three conditions ceases to exist, the controller  152  sends a signal to deactivate the electromagnets  138 , and so on. Monitoring of the relative position and speeds of the piston  104  and sleeve  122  is done by using proximity sensors  176 ,  178 , respectively. The array of such sensors  176 ,  178  that monitor position of the sleeve  122  is installed in the wall of cylinder  104  the same manner as it is done with the proximity sensors  176  that monitor position of the piston  104  as previously discussed. The sleeve sensors  178  may be installed either in line with the piston sensors  176  or in a separate line on the opposite side of the piston  104 . 
     Using signals from the sensors  176 , 178 , the relative position and speeds of the piston  104  and sleeve  122  are determined as follows:
         (a) the direction of movement of the piston  104  and sleeve  122  may be determined by the controller  152  based on time passed between two consecutive signals from two adjacent piston sensors  176  and time passed between two consecutive signals from two adjacent sleeve sensors  178 ;   (b) the relative position of the piston  104  and sleeve  122  may be determined by the controller  152  based on two latest signals—one from a piston proximity sensor  176  and the other from a sleeve proximity sensor  178 ; and,   (c) the type of piston stroke (i.e., determination whether the piston  104  is in the power stroke or not can be made based on the last signal received from the spark generator  170 , best seen in  FIG. 6 , and the number of signals received from the piston sensors  176  after the last signal generated by spark generator  170 ).       

     The complete and detailed logic of processing signals generated by the piston and sleeve sensors  176 ,  178  are believed to readily devisable by a person of ordinary skills in the art of engine controllers when the types and locations of the sensors  176 ,  178  are known. Consequently, such detailed timing information is neither disclosed nor further discussed herein. 
     Additional functionality may be provided by an electromagnet implementation of sleeve magnets  138 . By removing power from magnets  138  (now assumed to be electromagnets) so that sleeve  122  may be decoupled from piston  104 , any need for a mechanical clutch eliminated. 
     In conventional engines, cylinders are typically cooled by large external fins on the outside of the cylinders (e.g., motorcycle engines). In most current automotive engines, a water jacket surrounds the cylinder(s) with a cooling liquid that is circulated through the water jacket. A radiator or other heat exchange mechanism cools the circulating liquid. 
     Because connecting rods  128  or yoke  144  are disposed on the outside of cylinder  102 , neither of such prior art cooling solutions are practical. However, cooling conduits or tubes  142  may be disposed within the cylinder  102  wall. A cooling fluid (i.e., a liquid or gas) may be circulated through conduits  142  to cool cylinder  102  and piston  104 . The design of an external system to provide a cooling fluid to conduits  142  and to exchange heat from cylinder  102  is believed to be easily within the abilities of a person of average skill in the engine arts. Consequently, an external cooling system for internal combustion engine  100  is not further described or discussed herein. 
     It may be necessary to provide a mechanism for retarding or stopping movement of piston  102  as it approaches heads  108   a ,  108   b . Such a mechanism could be implemented mechanically using springs, not shown. As piston  104  approaches one of heads  108   a ,  108   b  it may contact a spring, not shown disposed within cylinder  102 . As the piston  104  continues its travel towards head  108   a  or  108   b , the spring will be compressed by the piston  104  so that the kinetic energy of piston  104  is absorbed. The size and strength of the spring may be chosen to provide the desired retardation of piston  104 . 
     In alternate embodiments, an electromagnetic retardation system may also be implemented. The electromagnetic retardation system operates similarly to electromagnetic brakes utilized in high-speed trains. The principle of their operation can be demonstrated by the following example: when a nonmagnetic metal plate (such as Aluminum, for instance) is moving fast in the proximity of a magnet perpendicular to the axis of its polarization, eddy currents are generated in the plate. These currents create magnetic field in such a direction that its interaction with the magnetic field of the magnet creates a force resisting to the movement of the plate, (i.e., a retardation force is applied to the plate). The electromagnetic retardation mechanism in the present invention can be executed by installing one or several magnets or electromagnets outside the cylinder, polarized radially with respect to the cylinder axis. When the piston is approaching a cylinder head, the magnets or electromagnets interact with the eddy currents generated in the nonmagnetic metal that piston is made of (for instance, aluminum or its alloys). This interaction results in retardation of the piston. In order to increase the effectiveness of this mechanism, the ferromagnetic cores of the solenoids shall, preferably, partially penetrate the cylinder wall (without penetrating the inner surface of the cylinder) so that the end surface of each core is as close to the approaching piston as practically possible. It will be recognized that no retardations system may be needed. It will be further recognized that many alternate methods or systems may be used to provide piston retardation and/or stopping. Consequently, the invention is not considered limited to the two examples of piston  104  retardation system chosen for purposes of disclosure. Rather the invention is intended to encompass any system or method for providing retardation of the movement of piston  104  within cylinder  102 . 
     While a single-cylinder engine has heretofore been disclosed, it is, of course, possible to gang multiple cylinders. Referring now also to  FIG. 5 , there is shown a simplified top plan, schematic view of a two-cylinder internal combustion engine including a pair of internal combustion engines  100  (labeled reference numbers  100   a ,  100   b , respectively). All elements remain the same but crankshaft  132  has an offset or “crank” shown therein. It will be recognized that any number of additional “engine”  100  elements may be combined into multi-cylinder engine systems, each element engine  100  being maintained by common support systems supplying air/fuel mixture supply, exhaust removal, spark supply and control systems, etc. Also, while  FIG. 5  shows a side-by-side configuration, other physical arrangement of engines  100  are possible. Such arrangements include horizontally opposed, slant arrangements, and radial arrangements. 
     Referring now also to  FIG. 6 , there is shown a simplified system block diagram of an electronic controller suitable for use with internal combustion engine  100 , generally at reference number  150 . 
     A controller  152  is connected to one or more engine sensors  176 ,  178  by electrical connection  156 . 
     A rotary valve actuator  158  is shown operatively connected to a rotary valve  160 . Optionally, a liner valve actuator  164  is shown operatively connected to a conventional, spring loaded valve  162 . Rotary actuator  158  is connected to controller  152  by electrical connection  166 . Optional linear actuator  164  is connected to controller  152  by auxiliary electrical connection  168  in combination with electrical connection  166 . 
     A spark generating mechanism  170  is shown connected to controller  152  by electrical connection  172 . 
     A programming input  174  is provided to controller  152 . 
     Controller, specifically process control controllers are believed to be well known to those of skill in the engine control arts. Consequently, no additional description of controller  152  is provided herein—any suitable controller known to those of skill in the art may be utilized. 
     Sensors  176 ,  178  may be any combination of optical, magnetic, or physical sensors that generate signals as piston  104  passes a predetermined point or points along cylinder  102 . Each of the sensors generates an electrical signal suitable for recognition by controller  152 . 
     Rotary valve actuator  158  may be implemented using a rotary solenoid. A return spring (e.g., a torsion spring), not shown may be used if necessary. In alternate embodiments, a bi-directional rotary solenoid may be used. In still other alternate embodiments, a stepper motor with an appropriate controller embedded in controller  152  may be used to actuate rotary valve  160 . 
     Optionally, a linear actuator  164  may be used to open a conventional spring loaded valve. 
     Spark generating mechanisms  170  are also believed to be well known to those of skill in the art. It will be recognized that controller  152  provides necessary spark timing and advance function based upon input from sensors  176 ,  178 . 
     It will be recognized that four valve actuators and spark signals for two spark plugs are required for a single-cylinder version of the internal combustion engine of the invention. When multiple cylinders are combined, it will be recognized that controller  152  is required to generate appropriate control outputs to control at least four valves and two spark plugs per cylinder. 
     Further, controller  152  can provide control of electromagnets  138  both for selectively powering electromagnets  138  as required in order to synchronize the movements of the sleeve and piston and for disconnecting the sleeve from the piston when a clutch function is required. 
     Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the example chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention. 
     Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims.