INTERNAL COMBUSTION ENGINE WITH ROTATING PISTONS AND CYLINDERS AND RELATED DEVICES AND METHODS OF USING THE SAME

Abstract

The present invention provides a novel internal combustion engine design and methods for using the same. The internal combustion engine of the present invention may include two rotors on which the pistons and cylinders and pistons are mounted, respectively. A plurality of cylinders mounted on a cylinder rotor, and a plurality of pistons mounted on a piston rod rotor, where the arrangements of the pistons and cylinders are complementary and each piston is paired with one of the cylinders. The cylinder rotor and the piston rod rotor may be position at oblique angle relative to one another, such that their central axes are located on a same plane, but the axes are not coaxially aligned and intersect on that plane.

Claims

1. A rotary engine, comprising: a. a piston rotor having a plurality of pistons thereon and positioned on a first rotational axis; b. a cylinder rotor having a plurality of cylinders thereon and positioned on a second rotational axis; and c. a power shaft for transmitting rotational motion from one of the piston rotor and cylinder rotor to a transmission system for providing mechanical power to another system, wherein the first rotational axis and the second rotational axis are oblique relative to one another, and each of said plurality of pistons is nested in one of said plurality of cylinders and the rotation of said piston rotor and said cylinder rotor is driven by combustion of a fuel in said cylinders.

2. The engine of claim 1, wherein the first and second rotational axes are positioned on a same plane, wherein an angle between the first rotational axis and the second rotational axis is in a range of about 120° to about 160°.

3. (canceled)

4. (canceled)

5. (canceled)

6. (canceled)

7. (canceled)

8. (canceled)

9. The engine of claim 1, wherein due to the relative angle of the piston rotor and the cylinder rotor, synchronous rotation of the piston rotor and the cylinder rotor results in a reciprocating motion of each piston within the corresponding cylinder, wherein the piston head of each piston penetrates furthest into the corresponding cylinder at a proximal point in its rotational path that is nearest to the cylinder rotor and the piston is at its most retracted point in corresponding cylinder at a distal point in its rotational path that is furthest from the cylinder rotor.

10. (canceled)

11. (canceled)

12. (canceled)

13. (canceled)

14. The engine of claim 9, wherein said engine is a four-stroke engine and the combustion cycle is completed in two full rotations of the piston rotor and the cylinder rotor.

15. The engine of claim 14, wherein each stroke of said combustion cycle occurs over a 180° turn of the piston rotor and cylinder rotor.

16. The engine of claim 1, further comprising a fuel intake system comprising an intake manifold, wherein said intake manifold includes a tube that is connected to said cylinder rotor and rotates with said cylinder rotor.

17. (canceled)

18. The engine of claim 17, wherein said tube is concentric with the cylinder rotor and includes fuel delivery passages that are in fluid communication with each of said plurality of cylinders in said cylinder rotor.

19. (canceled)

20. (canceled)

21. (canceled)

22. (canceled)

23. The engine of claim 18, wherein each of said plurality of cylinders includes an intake valve in fluid communication with said tube, and is opened by the vacuum created by an intake stroke of a corresponding piston.

24. The engine of claim 1, further comprising an exhaust system comprising an exhaust manifold, wherein each of said plurality of cylinders includes an exhaust valve in fluid communication with said cylinder and an exhaust conduit, wherein said exhaust conduit is in fluid communication with said exhaust manifold.

25. (canceled)

26. (canceled)

27. The engine of claim 24, wherein said exhaust conduits are connected to said cylinder rotor and rotate with said cylinder rotor.

28. (canceled)

29. (canceled)

30. The engine of claim 28, wherein said exhaust pipe is nested in said power shaft.

31. The engine of claim 24, further comprising exhaust valve timing system includes a cam drum that rotates independently of said power shaft.

32. The engine of claim 31, wherein the cam drum is in direct mechanical communication with the cylinder rotor via a gearing system that rotates said cam drum at a pre-determined speed relative to said cylinder rotor.

33. The engine of claim 32, wherein said cam drum includes at least one cam for actuating the exhaust valve of each of said plurality of cylinders, wherein said at least one cam actuates said exhaust valve of each of said plurality of cylinders during exhaust stroke.

34. (canceled)

35. (canceled)

36-87. (canceled)

88. A method of generating propulsive force, comprising: a. positioning a plurality of pistons connected to a piston rotor positioned on a first rotational axis in a plurality of cylinders positioned on a cylinder rotor positioned on a second rotational axis to form a plurality of paired pistons and cylinders, wherein the first rotational axis and the second rotational axis are oblique relative to one another; and b. combusting a fuel in said paired pistons and cylinders in a sequential pattern to drive rotation of said piston rotor and said cylinder rotor, wherein said rotation of one of said piston rotor and said cylinder rotor drives rotation of a power shaft for transmitting rotational motion from one of the piston rotor and cylinder rotor to a transmission system for providing mechanical power to another system.

89. The method of claim 88, wherein the first and second rotational axes are positioned on a same plane, wherein an angle between the first rotational axis and the second rotational axis is in a range of about 120° to about 160°.

90-120. (canceled)

121. The method of claim 88, wherein said plurality of pistons and plurality of cylinders is at least five and each have a distance of about 72° away from immediately adjacent pistons and cylinders and have a staggered firing order.

122. The method of claim 121, wherein said staggered firing order has a repeating combustion sequence wherein a first piston cylinder is followed by a third piston cylinder, followed by a fifth piston cylinder, followed by a second piston cylinder, followed by a fourth piston cylinder, and the sequence repeats starting with the first piston cylinder.

123. A method of fluid movement, comprising: a. positioning a plurality of pistons connected to a piston rotor positioned on a first rotational axis in a plurality of cylinders positioned on a cylinder rotor positioned on a second rotational axis to form a plurality of paired pistons and cylinders, wherein the first rotational axis and the second rotational axis are oblique relative to one another; and b. moving a fluid through said paired pistons and cylinders in a sequential pattern, wherein said rotation of one of said piston rotor and said cylinder rotor results in movement of said fluid from said cylinders into an exhaust system.

124. The method of claim 123, wherein the first and second rotational axes are positioned on a same plane, wherein an angle between the first rotational axis and the second rotational axis is in a range of about 120° to about 160°.

125-163. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0061] FIG. 1 is a side view of an engine according to an embodiment of the present invention.

[0062] FIG. 2 is a cross-sectional view of an engine according to an embodiment of the present invention.

[0063] FIG. 3 is a perspective view of component systems of an engine according to an embodiment of the present invention.

[0064] FIG. 4A is a cross-sectional view of component systems of an engine according to an embodiment of the present invention.

[0065] FIG. 4B is a cross-sectional view of component systems of an engine according to an embodiment of the present invention.

[0066] FIG. 5 is a plan view of component systems of an engine according to an embodiment of the present invention.

[0067] FIG. 6 is a cross-sectional view of component systems of an engine according to an embodiment of the present invention.

[0068] FIG. 7 is a side view of an engine according to an embodiment of the present invention.

[0069] FIG. 8 is a cross-sectional view of an engine according to an embodiment of the present invention.

[0070] FIG. 9 is a perspective view of component systems of an engine according to an embodiment of the present invention.

[0071] FIG. 10 is a distal bottom view of component systems of an engine according to an embodiment of the present invention.

[0072] FIG. 11 is a cross-sectional side view of component systems of an engine according to an embodiment of the present invention.

DETAILED DESCRIPTION

[0073] Reference will now be made in detail to certain embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in reference to these figures and certain implementations and examples of the embodiments, it will be understood that such implementations and examples are not intended to limit the invention. To the contrary, the invention is intended to cover alternatives, modifications, and equivalents that are included within the spirit and scope of the invention as defined by the claims. In the following disclosure, specific details are given to provide a thorough understanding of the invention. References to various features of the “present invention” throughout this document do not mean that all claimed embodiments or methods must include the referenced features. It will be apparent to one skilled in the art that the present invention may be practiced without these specific details or features.

[0074] Reference will be made to the exemplary illustrations in the accompanying drawings, and like reference characters may be used to designate like or corresponding parts throughout the several views of the drawings. FIGS. 1-6 provide views of an exemplary embodiment of a novel internal combustion engine having a rotary piston and cylinder design.

[0075] The engine of the present invention provides a rotary cylinder and piston system that drives a power shaft to transmit power to a power transmission system for various uses, including powering an automobile, powering a generator, powering a pumping system, and other applications. The engine 100 may be enclosed in an engine housing 101, enclosing the cylinder and piston rotors, as well as other systems, such as the intake and exhaust systems. A power shaft 102 may traverse the engine housing 101 such that it may deliver power to a power transmission assembly (not shown), such as a vehicle transmission. An exhaust pipe 103 may be nested within the power shaft and may allow for the removal of combustion exhaust from the engine housing and may be routed to a venting system. The exhaust pipe 103 may rotate with the power shaft and connect with a stationary system in a downstream location. The power shaft 102 may be in mechanical connection with a cylinder rotor, such that the rotation of the cylinder rotor rotates the power shaft 102. An idler shaft 105 may be present to connect to and hold a piston rotor in position within the engine housing 101 to position the piston rotor in proper orientation relative to the cylinder rotor and allow for free rotation of the piston rotor. The engine 100 may also include an engine cooling system that includes an oil pump and delivery system that works in coordination with cooling fins 155 operable to absorb thermal energy from the interior of the engine 100 and radiate it to the ambient air.

[0076] FIG. 2 provides a cross-sectional view of the engine 100 showing most of the major internal parts of the embodiment. The piston rotor 110 and cylinder rotor 120 are shown in profile positioned at an oblique angle relative to one another within the engine housing 101. The rotors meet at a central plane (e.g., a vertical plane) that may be a pre-determined distance between the cylinder rotor 120 and piston rotor 110. In the embodiment shown in the FIGS. 1-2, the central plane may be equidistant from the piston rotor 110 and the cylinder rotor 120. The angles of the cylinder rotor 120 and piston rotor 110 may be the same relative to the central plane. The angled arrangement of the cylinder rotor 120 and the piston rotor 110 creates an oscillating distance between corresponding piston heads and cylinders as the cylinder and piston rotors synchronously rotate. As shown in FIG. 2, there are multiple pistons 111a and 111b connected to the piston rotor 110. The pistons 111a and 111b include piston heads 112a and 112b nested in cylinders 121a and 121b. At the top of the rotational path of the pistons and cylinders, where piston head 111a and cylinder 112a are positioned in FIG. 2, the piston head 112a is at top dead center. At this position, the cylinder rotor 120 and the piston rotor 110 are in their closest proximity and the piston head 112a is fully inserted into the corresponding cylinder 121a. As the paired cylinder 121a and piston 111a rotate away from top dead center, they progressively move apart until they reach the bottom of the rotational path 180° from top dead center (at bottom dead center), where piston 111b and corresponding cylinder 121b are positioned in FIG. 2. As the paired cylinder and piston rotate back toward the top of the rotational path, the piston and cylinder progressively move together.

[0077] As shown in FIG. 2, cylinders 121 may be fixedly connected to a cylinder rotor 120 in an orthogonal or substantially orthogonal orientation. In the embodiment shown in the FIGS., the cylinders 121 may be positioned in a square arrangement of four cylinders with cylinders arranged equidistantly around the perimeter of the cylinder rotor 120. The piston rods of pistons 111 may be arranged in a corresponding pattern on the piston rotor 110. In the embodiment shown in the FIGS., the piston rods 112 may be connected to the piston rotor 110 by movable joints with one degree of freedom, for example a pivoting joint.

[0078] The piston heads 112a and 112b may be connected to the corresponding piston rods 111a and 111b by movable joints. To accommodate the angled arrangement of the piston rotor 110 and the cylinder rotor 120, the piston heads 112 may be connected to the rods by a movable joint, such as a ball joint to allow 360° rotation with two degrees of freedom relative to the ball joint. The angling of the piston rods 111 relative to the axes of the cylinders 121 may be limited to about 30° or less within a limited angle range relative to the central axis of the corresponding cylinder 121, allowing limited movement to accommodate the geometry of the piston cylinder 121. The moveable joint may allow for the piston heads 112 to reciprocate in and out of the corresponding cylinder 121 with sufficient clearances between the piston rods and the walls of the cylinders without interference or seizing.

[0079] There are several rotating elements that are connected to the spinning cylinder rotor 120 that allow for the system to work efficiently with the rotational action of the cylinders and pistons. The cylinder rotor 120 may be in mechanical connection with a power shaft 130 that translates the rotation of the cylinder rotor 120 to a transmission system (not shown) to utilize the power generated by the engine 100. The power shaft 130 may be fixedly connected to the cylinder rotor 120 such that they rotate together at the same rotational velocity. The intake and exhaust systems as shown in FIGS. 3 and 4 may also be positioned on the cylinder rotor 120 such that they rotate with the cylinder rotor 120 as well. The cylinder rotor 120 may include both intake ports for intake of air-fuel mixture during the intake stroke and exhaust ports to expel the combustion exhaust gas during the exhaust stroke. Each cylinder may have at least one intake port and at least one exhaust port in the cylinder rotor at the top of the cylinder.

[0080] FIG. 3 shows a perspective view of the cylinder rotor 120, exhaust system intake system, and power shaft 130 in working assembly. Some structures are shown as transparent for illustrative purposes. The exhaust system may include exhaust valves 135 in fluid communication with each of the cylinders 121, which may control the passage of the exhaust gas through an exhaust port into an exhaust conduit 136 during the exhaust stroke. Each exhaust valve 135 may be operated and opened by a cam system that includes a drum 140, which may turn freely with respect to the power shaft 130, but that is in mechanical connection with the rotating cylinder rotor 120, e.g., through a gearing system that times the rotation of the drum 140 such that cams thereon engage and open an exhaust valve 135 at the exhaust stroke for the corresponding cylinder 121. The cam system may include gearing with a ratio that allows it to spin at a different rotational speed than that of the cylinder rotor 120. The cam system gearing may be such that the drum 140 rotates in the same direction as the power shaft 130 at, e.g., one half the rotational speed of the cylinder rotor 120, and on a bearing. In such embodiments, four cam lobes may protrude from the drum to engage valve push rods or other engagement structures of the exhaust valves 125 of each cylinder 121. The cam lobes may be staggered along the axial dimension of the drum 140 and the exhaust valve push rods may be correspondingly staggered such that each cam lobe only engages with the exhaust valve of a particular cylinder 121, allowing the exhaust valves to remain closed during the other stages of the combustion cycle.

[0081] An exhaust conduit 136 may be connected to each of the cylinders 121 for passing the exhaust gas to an exhaust manifold 137 that delivers the exhaust gas into the exhaust collection pipe 138. The exhaust manifold 137 may be incorporated into the power shaft 130, where each of the exhaust conduits 136 routes from the exhaust valve 135 of the corresponding cylinder 121 radially inward toward the power shaft 130. The exhaust conduits 136 may connect with an exhaust manifold 137, which may be a cylindrical collar around the power shaft 130. The exhaust conduits 136 may connect with a port in the exhaust manifold 137 that is in fluid connection with the exhaust pipe 138, which rotates with the power shaft 130. The exhaust pipe 138 may be nested within the power shaft 130 and rotate therewith. The exhaust pipe 138 may deliver the exhaust to a stationary receiving pipe or plenum to which the distal end of the exhaust pipe 138 is connected via a rotary union. Because the exhaust pipe 138 rotates with the power shaft 130, a rotary union or joint is required to pass the exhaust gas to a static or non-rotating structure. The exhaust pipe may include at least one distal port that allows the exhaust gas to pass into the static structure. The exhaust pipe 138 may be a ceramic material, or the interior surface thereof may be lined with ceramic material in order to prevent corrosion and accumulation of exhaust residue.

[0082] As shown in FIGS. 3 and 6, each cylinder 121 may include an intake port and valve 125a that is in fluid communication with an intake manifold 126. The intake manifold 126 may deliver fuel (e.g., an air fuel mixture) to the intake valves 125 associated with each cylinder. The intake manifold 126 may take the form of a ring chamber positioned at predetermined radius relative to the power shaft 130 and may be in alignment with the intake ports and valves 125. In some embodiments, the intake manifold 126 may include a receiving channel 126a along its entire length on an opposite side thereof from the cylinder rotor 120. The receiving channel 126a may be configured to receive a throttle ring 127 having a complementary shape to that of the receiving channel 126a such that the throttle ring 127 can be adjustably nested within the receiving channel 126a. An adjustable gap 128 may be present between the throttle ring 127 and the receiving channel 126a for allowing air to flow into the intake manifold 126 to provide the air in the air-fuel mixture. The throttle control of the engine may adjust the proximity of the throttle ring 127 in order to adjust the choke of the engine 100. The throttle ring 127 may be in static position relative to the cylinder rotor 120 with the gap 127a between the receiving channel 126a and the throttle ring 127 allowing for the rotation of the intake manifold 126, while the throttle ring 127 remains static.

[0083] The throttle ring 127 may be attached to the motor housing 101 or a frame via biased connections that bias the throttle ring 127 toward the closed position. For example, the throttle ring 127 may be connected to the motor housing or frame via studs and biasing springs (not shown) biasing the throttle ring 127 toward the closed position. The studs may include stops that prevent the throttle ring from contacting the receiving channel of the intake manifold 126, preventing full choke. The engine 100 may have a throttle control (not shown) in mechanical connection with the throttle ring 127, allowing an operator to adjust the proximity of the throttle ring 127 to the receiving channel 126a, and thereby adjust the choke of the engine 100.

[0084] A fuel injector 128 may be connected to the throttle ring 127 for passing fuel into the intake manifold 126. The fuel injector 128 may be positioned over the point at which the intake valve 125 is opened during the intake stroke and the intake port is exposed allowing the passage of the fuel (e.g., an air-fuel mixture) through the intake port. The fuel injector 128 may be timed to spray fuel into the intake manifold 126 as the intake valve 125 opens, allowing fuel (e.g., the air-fuel mixture) through the intake port and into the open cylinder 121. Air may be introduced into the intake system through the gap 126a between the throttle ring 127 and the intake manifold 126 via passages in the engine housing around the intake system.

[0085] An intake valve 125 may control the passage of the air-fuel mixture through the intake port into the corresponding cylinder 121 during the intake stroke. In some embodiments, the intake valve 125 may be operated and opened by negative pressure during the intake stroke, and the intake valve 125 may remain closed during the other stages of the combustion cycle. In some embodiments, the low pressure generated in the cylinder 121 during the intake stroke may be sufficient to open an intake valve 125 for the cylinder 121 to allow the entry of the fuel. The intake valve 125 may include a seated structure in the intake port that is held in the seated position by a biasing device, such as an intake valve spring that biases the structure to the closed position. The force applied by the intake valve spring 129 to the valve structure 125 may be overcome by the vacuum in the cylinder 121 during the intake stroke.

[0086] FIG. 7 illustrates an engine according to an embodiment of the present invention. A rotary cylinder and piston system drives a power shaft to transmit power to a power transmission system for various uses, including powering an automobile, powering a generator, powering a pumping system, and other applications. The engine 200 may be enclosed in a housing 101 as shown in FIG. 1. A power shaft 205 may have a spindle 204 operable to couple to a power transmission assembly (not shown), such as a vehicle transmission. The power shaft 205 may be supported by bearings 201 that are secured to a frame 202 and a housing (not shown). On the cylinder rotor 220, an exhaust shaft 230 may be secured to the frame 202. The piston rotor 210 and cylinder rotor 220 are positioned at an oblique angle relative to one another. The rotors meet at a central plane (e.g., a vertical plane) that may be a pre-determined distance between the cylinder rotor 220 and piston rotor 210. In the embodiment shown in FIGS. 7-11, the central plane may be equidistant from the piston rotor 210 and the cylinder rotor 220. The angles of the cylinder rotor 220 and piston rotor 210 may be the same relative to the central plane. The angled arrangement of the cylinder rotor 220 and the piston rotor 210 creates an oscillating distance between corresponding piston heads and cylinders as the cylinder and piston rotors synchronously rotate. As shown in FIG. 7, multiple piston rods 211a 211b connect the piston heads 212a, 212b to the piston rotor 210. There is one piston rod and piston head for each cylinder in the engine assembly. Each piston heads 212a, 212b corresponds to a cylinder 221a, 221b (e.g., combustion chamber). Piston 212a and cylinder 221a are illustrated with the dotted lines and are positioned at the top of the cylinder head 255a and at the peak of the combustion cycle (e.g., top dead center). At this position, the cylinder rotor 220 and the piston rotor 210 are in their closest proximity, and the piston head 212a is fully inserted into the corresponding cylinder 221a. As the paired cylinder 221a and piston 212a rotate away from top dead center, they progressively move apart until they reach the bottom of the rotational path 180° from top dead center (at bottom dead center), as illustrated by piston 212b and the corresponding cylinder 121b in FIG. 7. As the paired cylinder and piston rotate back toward the top of the rotational path, the piston and cylinder progressively move together.

[0087] An intake air distributor 240 may collect air and receive fuel from an injector 248 and mix together to form an air-fuel mixture that may be delivered to the cylinder head 255 through an intake runner 242. Each of the cylinders 221 in the cylinder rotor 220 may have a corresponding cylinder head 255 positioned between the air intake distributor 240 and the rotor 220. A cylinder head 255 may include a camshaft system, a spark plug 250, an intake port 223, an exhaust port 224, an intake flange 256, and an exhaust flange 257, illustrated in detail in FIGS. 8-11. The air intake distributor 240 may be in communication with a concentric throttle ring 241 that is operable to modulate the volumetric flow rate of air entering into the distributor 240 based on a throttle position. The throttle ring 241 may include a fuel injector 248, and a plurality of throttle roller pins 227 that connect to a plurality of slots 228 positioned concentrically around the frame 202. The slots 228 may provide a cam path (e.g., an oscillating, curved, or helical path) operable to guide the slots on a rotational and translational path when the throttle ring is actuated. There is typically one slot 228 corresponding to each throttle pin 227. The fuel injector 248 may be operable to modulate the quantity of fuel entering into the air intake distributor 240 based on the position of the throttle ring. The series of slots 228 provide a cam path for the throttle pins 227, the cam path may be operable to rotate and translate the throttle ring 214 around the frame 202, thus increasing a gap between the distributor 240 and the ring, thereby allowing more air to enter the system.

[0088] The piston head 221a at top dead center may have a corresponding cylinder head 255a as shown in FIG. 8 the cylinder head may include an intake port 223, an exhaust port 224, an intake valve 225, and an exhaust valve 226. The cylinder head 255 may expel exhaust from combustion through an exhaust manifold 231 that may be in fluid communication with the exhaust tube 232. Nesting therebetween the exhaust shaft 230 and the exhaust tube 232 is a cooling insert 233 that is operable to provide a moving fluid to absorb heat from the exhaust for routing to a heat exchanger (not shown). The cooling insert may have a series of channels 233F that allow the moving fluid to enter and exit the cooling insert 233. The piston head 212a may be secured to a spherical joint 215a that is fixed to the piston rod 211a. The piston rod 211a may have a counterweight 214a positioned after the piston rotor 210 and may have an oil channel 218 for routing lubrication to the spherical joint 215a and a piston head 221a contact location. The power shaft 205 may translate through the piston rotor 210 (e.g., stability shaft) and have on one end a CV joint 208 that is free to rotate with the cylinder rotor 210. This mounting location has no impedance on the rotation of the rotors and may help support the power shaft 205 such that the power shaft is not under a load of a cantilever beam.

[0089] FIG. 9 provides a side view of the cylinder rotor 220 with the intake runners 242, and distributor 240 removed to expose the cam system. FIG. 10 provides a bottom view of the cylinder heads 255 with the combustion chambers 221 and rotor 220 removed. FIG. 11 provides a cross-sectional view about line C-C illustrated in FIG. 10 to illustrate further the frame 202, air distributor 240, exhaust shaft 230, cylinder heads 255, and valvetrain components. The line C-C is symmetrically positioned about the combustion chamber 255a, and symmetrically positioned about the combustion chamber 255b, the centerline of the cylinders is position about 144° apart from each other. Each of the cylinders may be positioned 72° away from immediately adjacent cylinders. Each of the cylinder heads may have an independent valvetrain that is operable to provide the air-fuel mixture to the combustion chamber 255 and expel exhaust gases to the exhaust tube 232. The independent valvetrain includes a camshaft 261, intake valve 225, exhaust valve 226, exhaust cam 262, and an intake cam 263. The camshaft 261 may have an exhaust cam 262, and intake cam 263 positioned 90 degrees from each other about the central axis of the camshaft 161. Each of the cams is of the closed-form type, which provides a slot orthogonal to the cam lobe, thereby providing a path to open and close the valve without using a spring. The intake cam 263 and exhaust cam 262 may be connected to their respective valves with a valve retainer 269. Although each of the cylinder heads has an independent valvetrain, the timing of opening and closing each cam lobe corresponds to the rotation of the piston rotor 210 and cylinder rotor 220.

[0090] The camshaft 261 may have a cam gear 264 that may mesh with a reduction gear 265 that shares a common shaft with a timing gear 266. The timing gear 266 meshes with a control gear 267 that is fixed to frame 202 and does not move when the cylinder rotor and piston rotor are in rotation. As the cylinder rotor 220 rotates around the frame 202, the timing gear 266 (e.g., fan gear) follows the path provided by the control gear 267. The reduction gear 265 rotates at the same rate as the timing gear 266 because they are mounted on the same shaft. The reduction gear 265 meshes with the cam gear 264, and because the reduction gear 265 has one-fourth the number of gear teeth as the cam gear 264, the exhaust cam and intake cam only perform one cycle for every two rotations of the cylinder rotor. Thus the camshaft 261 performs one revolution for every two revolutions of the timing gear 266 around the control gear 267 to provide a four-stroke action of the pistons and rods. During an intake stroke, the intake valve 226 is configured in the open position to allow the air-fuel mixture to enter the combustion chamber 221, this occurs when the piston 212 is translating away from the cylinder head 255. As the cylinder rotor 220 continues rotation, the camshaft 261 rotates, thus configuring the intake valve 226 in a closed position. The piston 212 then begins a compression stroke and advances towards the cylinder head 255. When the piston 212 reaches top dead center, a power stroke begins and a spark plug 250 ignites the compressed air-fuel mixture, and combustion occurs, thus translating the piston 212 away from the cylinder head 255. As the cylinder rotor continues rotation, the camshaft rotates and configures the exhaust valve 225 to the open position allowing exhaust gases to exit out of the combustion chamber 221 as the piston 212 advance to the top of the cylinder head 255 during the exhaust stroke.

[0091] It is to be understood that variations and modifications of the present invention may be made without departing from the scope thereof. It is also to be understood that the present invention is not to be limited by the specific embodiments disclosed herein, but only in accordance with the appended claims when read in light of the foregoing specification.