Poppet valve and engine using same

One embodiment of the present invention provides a poppet valve offering an increased valve area, comprising an outer valve head having an outer valve port and an inner valve head having an inner valve port. The inner valve head is rotatable relative to the outer valve head to align the inner and outer valve ports, thereby increasing the effective valve area of the poppet valve. The path created by aligning the inner and outer valve ports can be designed to mix air flowing through the poppet valve. Another embodiment of the present invention provides a valve guide containing a poppet valve having a guide pin, wherein the guide pin rests within a groove in the valve guide. As the poppet valve moves through the valve guide, the groove controls movement of the guide pin and causes the poppet valve to rotate relative to the valve guide.

BACKGROUND OF THE INVENTION

The operation of internal combustion engines is well known to those of skill in the art. For example, a typical one-cylinder, two-valve internal combustion engine includes a reciprocating piston which defines a combustion chamber for the combustion of a fuel charge comprising a fuel-air mixture, with the combustion chamber being the variable volume between the top of the piston and the cylinder head. The cylinder head contains an intake poppet valve (“intake valve”), an exhaust poppet valve (“exhaust valve”), and an ignition source such as a spark plug. The piston is connected via a connecting rod to a crankshaft which converts the reciprocating linear motion of the piston into a useful torque on the crankshaft.

During the intake stroke, the piston moves downward and away from the cylinder head, lowering the pressure in the combustion chamber relative to the pressure on the other side of the intake valve. As the piston travels downward, the intake valve extends into the combustion chamber, or “lifts,” wherein the pressure differential between the combustion chamber and the intake port causes the fuel charge to flow into the combustion chamber. The intake valve then closes and the fuel mixture is compressed in the combustion chamber as the piston travels toward the cylinder head. At top dead center, the piston is at its maximum vertical position and the fuel charge is at its maximum compression. The fuel mixture is then ignited, driving the piston downwards and generating a torque on the crank shaft. The exhaust valve then opens and the positive pressure of the exhaust gas causes it to flow out of the combustion chamber and into the exhaust port.

As understood by one of skill in the art, the amount of fuel charge that can flow into the combustion chamber during the limited time that the intake valve is open is a function of the “intake valve area,” which consists of the two-dimensional area between the intake valve at maximum lift and the cylinder head. Since an internal combustion engine is essentially an air pump, the power and efficiency of an internal combustion engine is directly proportional to the intake valve area. Similarly, the power and efficiency of an internal combustion engine is also proportional to the amount of exhaust gas that can be expelled from the combustion chamber during the limited time that the exhaust valve is open. The amount of exhaust gas expelled is a function of the exhaust valve area. Similarly, the power and efficiency of an internal combustion engine is also a function of how well the fuel and air have been mixed just prior to combustion.

Poppet valves as known in the art generally comprise a narrow valve stem which rapidly widens at one end into a circular valve head. The valve head fits into a corresponding circular opening in the cylinder head such that the combustion chamber is a closed volume when the intake and exhaust valves are closed. Modern internal combustion engines sometimes use more than two total valves to increase the total intake and exhaust valve areas, providing greater engine efficiency and power output. For example, some internal combustion engines use two intake valves and two exhaust valves, which provide a larger total valve area than a two-valve design. Some engines even use three intake valves and two exhaust valves to further increase total valve area. However, there is a limit to the number of valves that can be used in a given cylinder head because the area of the cylinder head in which the valves rest is finite. Additionally, using a very large number of small valves does not improve engine efficiency because a very small valve area has a greater flow resistance per unit area than a larger valve area.

Internal combustion engines use fuels that are derived from crude oil, the supply of which is increasingly finite and unstable. When combustion engines burn such fuels they produce emissions that cause a negative impact on the environment—and governments have promulgated and enforced increasingly stringent environmental regulations as a result. But alternatives to the internal combustion engine are few, and they are costly. In light of these and other developments, there is an increasing need in the art to extract more power and efficiency from combustion engines.

A poppet valve that offered an increased valve area would produce more power per unit of fuel than existing poppet valves, thus enabling manufacturers to produce engines that consume less fuel without sacrificing power. The same results would inhere from the use of a poppet valve that caused the fuel charge to mix more thoroughly in the combustion chamber, such as by creating a vortex in the combustion chamber. Moreover, a poppet valve combining these elements would increase fuel efficiency more than would a poppet valve offering either element standing alone. A combustion engine using poppet valves that offered an increased valve area or caused the fuel charge to mix more thoroughly, or both, would, by increasing fuel efficiency, enable users of combustion systems to reduce their energy consumption. This, in turn, would materially contribute to the more efficient utilization and conservation of energy resources. The reduction in energy consumption also would lead to a reduction in harmful emissions, thus materially enhancing the quality of the environment.

SUMMARY OF THE INVENTION

In one embodiment of the present invention, a poppet valve is provided. The poppet valve comprises an outer valve head comprising an outer valve port and an inner valve head comprising an inner valve port. An inner valve port can be a closed two-dimensional area, or the inner valve port can be an open two-dimensional area. Similarly, the outer valve port can be a closed two-dimensional area, or the outer valve port can be an open two-dimensional area. The inner valve head is rotatable relative to the outer valve head so that the outer valve port can be aligned with the inner valve port, thereby increasing the effective valve area of the poppet valve.

In another embodiment of the present invention, a poppet valve is provided. The poppet valve comprises an outer valve head comprising an outer valve port and an inner valve head comprising a valve “port cover.” The port cover is a solid portion of the inner valve head which can obstruct flow through the outer valve port. The inner valve head is rotatable relative to the outer valve head so that the port cover can open a path through the outer valve port, thereby increasing the effective valve area of the poppet valve.

In a further embodiment of the present invention, a poppet valve is provided. The poppet valve comprises a hollow outer valve containing an inner valve. The outer valve comprises an outer valve stem and an outer valve head, with the outer valve head having one or more outer valve ports. The inner valve comprises an inner valve stem and an inner valve head, with the inner valve head having one or more valve port covers corresponding to the one or more outer valve ports. The inner valve rotates relative to the outer valve, causing the valve port covers to open and close the outer valve ports, thereby increasing the effective valve area of the poppet valve.

Another embodiment of the present invention provides a poppet valve comprising a hollow outer valve containing an inner valve. The outer valve comprises an outer valve stem and an outer valve head, with the outer valve head having one or more outer valve ports. The inner valve comprises an inner valve stem and an inner valve head, with the inner valve head having one or more inner valve ports corresponding to the one or more outer valve ports. The inner valve rotates relative to the outer valve, causing the outer valve ports and the inner valve ports to align, thereby increasing the effective valve area of the poppet valve. Further, the outer valve ports and the inner valve ports can be arranged to improve mixing of the fuel charge in the combustion chamber. For example, in one embodiment, the outer valve ports and inner valve ports are arranged to create a spiral or vortex in the combustion chamber.

In yet another embodiment of the present invention, a guide pin is located on the outer valve stem of a poppet valve, with the guide pin being used to rotate the outer valve relative to the inner valve. In a further embodiment, the poppet valve may be located within a valve guide, wherein the valve guide includes a recessed timing groove in contact with the guide pin. The timing groove controls the movement of the guide pin as the poppet valve moves longitudinally through the valve guide, enabling the outer valve to rotate relative to the valve guide to selectively open and close the valve ports. As understood by one of skill in the art, any means may be used to prevent or control rotation of the inner valve relative to the outer valve, including mechanical, hydraulic, or electronic actuation. In further embodiments, two or more guide pins or timing grooves may be used.

In another embodiment of the present invention which includes a poppet valve, a guide pin is located on an inner valve stem and a timing window is located on an outer valve stem. The guide pin rests within the timing window, with the timing window defining the maximum degree of rotation of the inner valve relative to the outer valve. Further, the poppet valve may be located within a valve guide, wherein the valve guide includes a recessed timing groove in contact with the guide pin. The timing groove controls the movement of the guide pin as the poppet valve moves longitudinally through the valve guide, enabling the inner valve to rotate relative to the valve guide and selectively open and close the outer valve ports. In further embodiments, two or more guide pins, timing windows, or timing grooves may be used.

In a further embodiment of the present invention, a poppet valve is located within a valve guide, wherein the valve guide includes a longitudinal recessed groove and the outer valve includes a corresponding longitudinal ridge in contact with the groove, preventing the outer valve from freely rotating relative to the valve guide. The longitudinal ridge is additionally advantageous because it strengthens the outer valve stem.

Another embodiment of the present invention comprises an internal combustion engine having a combustion chamber and a poppet valve which allows air to flow from an intake passage into the combustion chamber. The poppet valve comprises an outer valve head having one or more outer valve ports, and an inner valve head having one or more inner valve ports. The inner valve rotates relative to the outer valve, aligning the inner and outer valve ports to create a plurality of paths through the poppet valve, thereby increasing the effective valve area of the poppet valve. In one embodiment, at least one path is designed to improve mixing of the fuel charge in the combustion chamber as air flows through the poppet valve. For example, one or both of the outer valve ports or the inner valve ports can be arranged to create a vortex or cyclone in the combustion chamber as air flows through the poppet valve.

In yet another embodiment of the present invention, a valve guide with a timing groove is provided. A poppet valve is located within the valve guide, with the poppet valve comprising a hollow outer valve containing an inner valve. The outer valve comprises an outer valve stem and an outer valve head, with the outer valve head having one or more outer valve ports. The inner valve comprises an inner valve stem and an inner valve head, with the inner valve head having one or more valve port covers corresponding to the one or more outer valve ports. The inner valve stem includes a guide pin which protrudes through a timing window in the outer valve stem, with the guide pin in contact with the timing groove. As the poppet valve moves longitudinally relative to the valve guide, the force exerted by the timing groove on the guide pin causes the inner valve to rotate relative to the valve guide, selectively opening and closing the outer valve ports. In one embodiment, the outer valve ports and/or port covers can be arranged to improve mixing of the fuel charge in the combustion chamber as air flows through the poppet valve. In another embodiment, the outer valve ports and/or port covers are arranged to create a vortex or swirling action in the combustion chamber as the fuel charge flows through the poppet valve.

In a further embodiment of the present invention, a method for operating an intake poppet valve in an internal combustion engine is provided, wherein the poppet valve comprises an inner valve head having an inner valve port and an outer valve head having an outer valve port. First, the piston moves away from the cylinder head, increasing the volume of the combustion chamber. Second, the poppet valve extends into the combustion chamber, enabling air to flow past the outer valve head into the combustion chamber. Third, the inner valve rotates in a first rotational direction relative to the outer valve, causing the outer valve port to open, enabling the fuel charge to flow into the combustion chamber through the outer valve port. Fourth, the poppet valve is retracted toward the cylinder head. Fifth, the inner valve is rotated relative to the outer valve in a direction opposite of the first rotational direction, causing the outer valve port to close. Sixth, the piston moves toward the cylinder head, decreasing the volume in the combustion chamber. Seventh, the outer head of the poppet valve rests against the cylinder head, closing the combustion chamber. Finally, the fuel charge in the combustion chamber is ignited. In further embodiments, one or more of the outer valve ports, inner valve ports, or valve port covers is or are arranged to improve mixing of the fuel charge in the combustion chamber as air flows through the poppet valve. For example, one or more of the outer valve ports and port covers can be arranged to create a vortex or swirling action in the combustion chamber as air flows through the poppet valve. Further, any embodiment of the poppet valve or valve guide of the present invention may be used with the present embodiment. One of skill in the art will also understand that the method of the current embodiment can be modified to operate an exhaust poppet valve in an internal combustion engine.

One of skill in the art will understand that any feature, element, or characteristic of any embodiment of the present invention can be used or combined with any feature, element, or characteristic of any other embodiment of the present invention. Unless otherwise expressly stated, it is in no way intended that any method or embodiment set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method or system claim does not specifically state in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that an order be inferred, in any respect. This holds for any possible non-express basis for interpretation, including matters of logic with respect to arrangement of steps or operational flow, plain meaning derived from grammatical organization or punctuation, or the number or type of embodiments described in the specification.

DETAILED DESCRIPTION OF THE INVENTION

The present invention has been illustrated in relation to embodiments which are intended in all respects to be illustrative rather than restrictive. Those skilled in the art will realize that the present invention is capable of many modifications and variations without departing from the scope of the invention.

The word “rotation” and the phrase “relative rotation” between any two components of the present invention refer to a relative rotation between the two components. As understood by one of skill in the art, “relative rotation” between a first component and a second component means that the first component may stay rotationally fixed while the second component rotates, that the first component rotates while the second component stays rotationally fixed, or that both the first and second components rotate simultaneously or at different times with respect to each other. Thus, in embodiments of the present invention which recite an inner valve rotating relative to, or with respect to, an outer valve, for example, the outer valve may be rotationally fixed while the inner valve rotates, the outer valve may rotate while the inner valve stays rotationally fixed, or both the inner and outer valves may rotate simultaneously with respect to each other. The words “align”, “aligned”, “alignment”, and “aligning” are defined herein to refer to a partial or full alignment between two components. Thus, an inner valve port is aligned with an outer valve port if there is any path through those inner and outer valve ports through which a substance, such as air, can flow, regardless of the shape or size of the path.

One embodiment of the present invention provides a poppet valve as shown inFIG. 1A. The poppet valve inFIG. 1Acomprises a hollow outer valve containing an inner valve. The outer valve comprises an outer valve stem101and an outer valve head106, with the outer valve head106having four outer valve ports103. The inner valve comprises an inner valve stem102and an inner valve head107, with the inner valve head107having four valve port covers104corresponding to the four outer valve ports103. The inner valve head107also comprises four inner valve ports105corresponding to the four outer valve ports103. In the embodiment ofFIG. 1A, one of skill in the art will see that the inner valve ports105comprise a closed two-dimensional area. The inner valve rotates relative to the outer valve, causing the valve port covers104to selectively open and close the outer valve ports103, thereby increasing the effective valve area of the poppet valve. In the embodiment ofFIG. 1Athe poppet valve is in the closed position, wherein the outer valve ports103are obstructed by the port covers104, preventing air from flowing through the outer valve ports103.

FIG. 1Billustrates the poppet valve embodiment ofFIG. 1Awith the poppet valve in the open position. In this embodiment, the inner valve has been rotated relative to the outer valve, wherein the outer valve ports103are not obstructed by the valve port covers104, and the outer valve ports103are aligned with the inner valve ports105, allowing air to flow through the poppet valve by flowing through the outer valve ports103and then flowing through the inner valve ports105. One of skill in the art will understand that embodiments of the present invention relating to a poppet valve can be used for any purpose and with regard to any type of substance, including solids, liquids, and gases. Accordingly, while some embodiments of the present invention describe a poppet valve useable with an internal combustion engine, these embodiments are descriptive and not limiting.

Another embodiment of the present invention provides a poppet valve comprising a hollow outer valve containing an inner valve, as shown inFIG. 2. The outer valve comprises an outer valve stem202and an outer valve head203, with the outer valve head having one or more outer valve ports204. The inner valve as seen in the figure comprises an inner valve stem and an inner valve head, with the inner valve head having one or more valve port covers and one or more inner valve ports corresponding to the outer valve ports204. In the embodiment ofFIG. 2, the inner valve rotates relative to the outer valve, causing the valve port covers to selectively open and close the outer valve ports204, thereby increasing the effective valve area of the poppet valve. In this embodiment, the one or more outer valve ports204and inner valve ports are arranged to improve mixing of the fuel charge in the combustion chamber as air flows through the poppet valve. As shown in the embodiment ofFIG. 2, the outer valve ports and the inner valve ports are arranged to create a swirl or vortex in the combustion chamber as air flows through the poppet valve. The swirling action produced by the poppet valve shown in the embodiment ofFIG. 2improves mixing of the fuel and air in the combustion chamber, enabling more power to be extracted from a given amount of fuel.

The embodiment ofFIG. 2can be extended by arranging the outer valve ports204and inner valve ports in a variety of ways to produce different mixing effects in the combustion chamber of an internal combustion engine. For example, in one embodiment, one or more of the outer valve ports204and/or inner valve ports may not be parallel to the outer valve stem202. In another embodiment, the outer valve ports204and/or the inner valve ports are each directed towards one part of the combustion chamber, such as towards the center line of the combustion chamber. In yet another embodiment, the outer valve ports204and/or the inner valve ports are arranged such that the incoming air is directed away from the center line of the outer valve stem202. In further embodiments, the outer valve ports204and/or the inner valve ports are directed to work in concert with other elements of the internal combustion engine to improve mixing of the fuel charge in the combustion chamber. For example, the outer valve ports204and/or the inner valve ports can be arranged to direct the fuel charge into grooves or channels in the top of the piston. One skilled in the art will appreciate that numerous outer valve port204and inner valve port arrangements are available to optimize the fuel charge mixing of a given internal combustion.

FIG. 3Ashows a perspective view of one embodiment of an inner valve head usable with any embodiment of the poppet valve of the present invention, including the poppet valves embodied inFIGS. 1A,1B,2,4A,4B,5, and6. InFIG. 3A, the inner valve head is a circular disc comprising four valve port covers for obstructing flow. For illustrative and discussion purposes only, the inner valve head ofFIG. 3Acan be combined with the outer valve ofFIG. 1Ato create an embodiment of the present invention. One of skill in the art can see that the valve port cover301is a solid portion of the inner valve head which prevents the fuel charge from flowing through the outer valve ports103when the poppet valve is in the closed position. When the poppet valve is in the open position, the four outer valve ports103are aligned with the four inner valve ports302, enabling air to flow through the poppet valve by flowing through the outer valve ports103and then by flowing through the inner valve ports302. One of skill in the art can see that the inner valve ports302are closed two-dimensional areas in the current embodiment.

FIG. 3Bshows a perspective view of another embodiment of an inner valve head usable with any embodiment of the poppet valve of the present invention, including the poppet valves embodied inFIGS. 1A,1B,2,4A,4B,5, and6. InFIG. 3B, the inner valve head comprises four valve port covers303as well as four inner valve ports304. One of skill in the art will see that the inner valve ports304are open two-dimensional areas. For illustrative and discussion purposes only, the inner valve head ofFIG. 3Bcan be combined with the outer valve ofFIG. 1Ato create an embodiment of the present invention. One of skill in the art can see that the valve port cover303is a solid portion of the inner valve head which prevents air from flowing through the outer valve ports103when the poppet valve is in the closed position. When the poppet valve is in the open position, the four outer valve ports103are not totally obstructed by the four valve port covers303, enabling the fuel charge to flow through the poppet valve by flowing through the outer valve ports103and through the inner valve ports304. One of skill in the art will see that the inner valve head shown in the embodiment ofFIG. 3Bdoes not have inner valve ports as in the embodiment ofFIG. 3Abecause the area between adjacent valve port covers303inFIG. 3Bis not closed by a connector around the circumference of the inner valve head as inFIG. 3A. Accordingly, the inner valve head depicted inFIG. 3Bmay have less mass than the inner valve head depicted inFIG. 3Abecause the valve port covers303are not connected as they are in FIG.3A. Thus, the inner valve head ofFIG. 3Bmay have less rotational inertia than the inner valve head ofFIG. 3A.

Another embodiment of the present invention, as disclosed inFIG. 4A, provides a valve guide for causing the inner valve of poppet valve embodiments of the present invention to rotate relative to the outer valve of poppet valve embodiments of the present invention. The embodiment ofFIG. 4Ais usable with any embodiment of the poppet valve of the present invention, including the embodiments shown inFIGS. 1A,1B,2,3A,3B,5, and6. For illustrative and discussion purposes only, the poppet valve embodiment ofFIG. 1Acan be combined with the valve guide embodiment ofFIG. 4Ato create a further embodiment of the present invention. In this embodiment, a guide pin405is located on the inner valve stem403and a timing window406is located on the outer valve stem402. The guide pin405rests within the timing window406and the timing window406defines the full range of rotation of the inner valve relative to the outer valve. The “valve closed” and “valve open” positions are located within the range of rotation defined by the timing window406.

As seen in the present embodiment, the valve guide401includes a recessed timing groove407in contact with the guide pin405. The timing groove407controls the movement of the guide pin405as the poppet valve moves longitudinally through the valve guide401. Thus, the timing groove406guides the guide pin405and causes the inner valve to rotate relative to the valve guide401. One of skill in the art will understand that various means can be used to control the rotation of the outer valve relative to the inner valve in a way usable with the embodiment ofFIG. 4A, including mechanical, hydraulic, or electronic means.

One embodiment for controlling rotation of the outer valve is shown inFIG. 4A. InFIG. 4A, the outer valve stem402includes a longitudinal ridge404which is located in a corresponding longitudinal groove of the valve guide401. The longitudinal ridge404prevents the outer valve from rotating relative to the valve guide401. Since the outer valve and the valve guide401do not rotate relative to each other, the guide pin405and timing groove407cause the inner valve to rotate relative to the outer valve, thereby selectively opening and closing the outer valve ports103of the poppet valve. Here, as seen in the current embodiment, the guide pin405is in the upper part of the timing groove407, causing the poppet valve to be in the closed position wherein the valve port covers104obstruct the valve ports103. Further, the longitudinal ridge404is additionally advantageous because it strengthens the outer valve stem402. As one of skill in the art will understand, two or more guide pins, timing windows, or timing grooves may be used with embodiments of the present invention.

FIG. 4Bdepicts the embodiments ofFIG. 4Awherein the poppet valve has moved longitudinally downward through the valve guide401. Since the poppet valve has traveled downward through the valve guide, the guide pin405has moved within the timing groove407, causing the inner valve to rotate relative to the outer valve in a clockwise direction. Thus, the poppet valve is in the open position, wherein the outer valve ports103and the inner valve ports105are aligned, allowing air to flow through the poppet valve by flowing through the outer valve ports103and then by flowing through the inner valve ports105. One of skill in the art will also see that the inner valve head of the embodiment ofFIG. 3Aor3B can be used with the embodiments ofFIGS. 4A and 4B.

The poppet valve and/or valve guide of each embodiment of the present invention can be used in an internal combustion engine as depicted inFIG. 5, including the embodiments discussed with regard toFIGS. 1A,1B,2,3A,3B,4A,4B, and6. For illustrative and discussion purposes only, the poppet valve as embodied inFIG. 1Ais used in the embodiment ofFIG. 5. As known to one of skill in the art, an internal combustion engine includes a reciprocating piston501which moves linearly within a cylinder502. The internal combustion engine includes a combustion chamber503, which is the volume between the top of the piston501and the cylinder head509. A spark plug506may be used as an ignition source. In the embodiment ofFIG. 5, air is traveling down the intake port510and into the combustion chamber503. The poppet valve is in the open position, such that the air is entering the combustion chamber503by flowing both around the outer valve head106and through the outer valve ports103and the inner valve ports105. One of skill in the art will understand that the internal combustion engine of embodiments of the present invention can be of numerous types, including gasoline, diesel, two-stroke, four-stroke, carbureted, fuel injected, direct fuel injected, and the like. Similarly, the internal combustion engine of embodiments of the present invention may be naturally aspirated or may use a forced induction system, including superchargers and turbo chargers as known to those skilled in the art. Also, one of skill in the art will understand that any means can be used to cause the inner valve to rotate relative to the outer valve, such as mechanical, hydraulic, and electric means.

One embodiment of the present invention for operating an intake poppet valve in an internal combustion engine is provided inFIG. 6. The internal combustion engine can be the internal combustion engine depicted inFIG. 5, but any type of internal combustion engine can be used. The method ofFIG. 6can also be used in non-engine applications as well. In the embodiment ofFIG. 6, the internal combustion engine comprises a cylinder head including a poppet valve, a combustion chamber, and a piston. The poppet valve of the present embodiment comprises an outer valve head and an inner valve head. The outer valve head comprises an outer valve port and an inner valve head comprising an inner valve port. The inner valve rotates relative to the outer valve to align the outer valve port with the inner valve port, creating a path through which air can flow. Any of the poppet valve and valve guide embodiments of the present invention may be used with the embodiment ofFIG. 6, including the embodiments shown inFIGS. 1A,1B,2,3A,3B,4A,4B, and5.

First in the embodiment ofFIG. 6, the piston moves601away from the cylinder head, increasing the volume in the combustion chamber. Second, the poppet valve extends602into the combustion chamber, enabling a fuel charge to flow past the outer valve head and into the combustion chamber. Next in the present embodiment, the inner valve head rotates603in a first rotational direction relative to the outer valve head, causing the outer valve port to align with the inner valve port, creating a path through which air can flow into the combustion chamber. As understood by one of skill in the art, steps601,602, and603may be performed in any order depending on the particular valve timing of the internal combustion engine.

Fourth in the present embodiment, the poppet valve is retracted604toward the cylinder head. The inner valve head is then rotated605relative to the outer valve head in a direction opposite of the first rotational direction, causing the outer valve port to close. Sixth, the piston moves606toward the cylinder head, decreasing the volume in the combustion chamber. Seventh, the outer head of the poppet valve rests607against the cylinder head, closing the combustion chamber. Finally, the fuel charge is ignited608in the combustion chamber. The inner valve head may be rotated relative to the outer valve head using at least one of mechanical, hydraulic, or electronic means as known to those skilled in the art. Steps604,605, and606may be performed in any order depending on the particular valve timing of the internal combustion engine, as understood by one of skill in the art.

In one embodiment extending the embodiment ofFIG. 6, the poppet valve comprises an outer valve stem connected to the outer valve head, and an inner valve stem connected to an inner valve head, wherein a guide pin is located on the outer valve stem. In a further embodiment extending the embodiment ofFIG. 6, the poppet valve further comprises a guide pin located on the inner valve stem and a timing window located on the outer valve stem, the guide pin located within the timing window to define the maximum rotation of the inner valve head relative to the outer valve head. Additionally, the poppet valve may be contained within a valve guide in the cylinder head, the valve guide comprising a timing groove on the inner surface of the valve guide and in contact with the guide pin, wherein the timing groove exerts a horizontal force on the guide pin as the poppet valve moves longitudinally relative to the valve guide, enabling the outer valve ports to selectively open and close. Further extending the present embodiment, the valve guide may include a longitudinal groove and the outer valve may include a longitudinal ridge in contact with the groove, wherein the groove and ridge prevent the outer valve from freely rotating relative to the valve guide.

In a further embodiment extending the embodiment ofFIG. 6, the outer valve port and the inner valve port are designed to improve mixing of the fuel charge in the combustion chamber. One of skill in the art will understand that either one or both of the inner valve ports and the outer valve ports can be designed to improve mixing in the combustion chamber. In one embodiment, the outer valve port and the inner valve port are arranged to create a swirling action in the combustion chamber when air passes through the poppet valve. One of skill in the art will understand that every outer and inner valve port arrangement discussed with respect to embodiments of the present invention may be used with the embodiment ofFIG. 6. Finally, the methods ofFIG. 6can be embedded in computer program products executable by a digital device, wherein digital devices include personal computers, laptops, personal digital assistants, digital processors embedded in automobiles, and the like.

While the invention has been described in detail in connection with specific embodiments, it should be understood that the invention is not limited to the above-disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alternations, substitutions, or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Specific embodiments should be taken as exemplary and not limiting.