Radial cam engine

Abstract

The described radial cam engine consists of piston assemblies arranged in a radial configuration. Inside the engine, the pistons move back and forth within the cylinders during the internal combustion process. The pistons are guided by a central cam and connected to followers that interact with the central cam. This central cam serves to rotate the drive shaft. The radial cam incorporates three different cam profiles, each designed for a specific stage of the engine's operation. These profiles are specially adjusted for the compression stroke, combustion stroke, and exhaust stroke. By utilizing different cam profiles for each stroke, the engine can optimize its performance throughout the combustion process.

Description

Technical Field

[0001] The present invention generally relates to a kind of radial cam engine.

Summary of the Invention

[0002] The described radial cam engine consists of a piston assembly arranged in a radial configuration.

[0003] Inside the engine, the piston moves back and forth in the cylinder during the internal combustion process.

[0004] The piston is guided by a central cam and connected to a follower that interacts with the central cam. This central cam serves to rotate the drive shaft.

[0005] The radial cams incorporate three different cam profiles, each designed for a specific stage of the engine operation.

[0006] These profiles are specially adjusted for the compression stroke, combustion stroke, and exhaust stroke.

[0007] By utilizing different cam profiles for each stroke, the engine can optimize its performance throughout the combustion process.

[0008] Other aspects of the present invention are also disclosed.

[0009] Any other forms that may fall within the scope of the present invention are contemplated, but the preferred embodiments of the present disclosure will be described herein by way of example only with reference to the accompanying drawings.

Brief Description of the Drawings

[0010]

Figure 1

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DETAILED DESCRIPTION OF THE INVENTION

[0011] The radial cam engine 100 includes at least one radially arranged piston assembly 101. In the illustrated embodiment, the engine 100 includes three piston assemblies 101, but the number can be changed in the embodiment.

[0012] Each piston assembly 101 includes a piston 102 that reciprocates within an internal combustion cylinder 103. The piston 102 may include a piston head 104 that fits within the cylinder 103 and a stem 105. The distal end of the stem may define a guided follower 106.

[0013] The guided follower 106 operably interacts with a central cam 107. The cam 107 rotates in the direction indicated by the direction indicator 112.

[0014] The cam 107 includes three different cam profiles including a combustion cam profile 108, an exhaust cam profile 109, and a compression cam profile 110.

[0015] The angle of the combustion cam profile 108 is approximately half the angle of the compression cam profile 110. Further, the angle of the exhaust cam profile 109 may be a larger angle than the compression cam profile 110.

[0016] In the illustrated embodiment, the combustion cam profile 108 can be between 50 and 80°, and in the illustrated embodiment, it can be about 64.5°.

[0017] Furthermore, the compression cam profile 110 can be between 110 and 150°, and in the illustrated embodiment, it can be about 130°.

[0018] Furthermore, the angle of the exhaust cam profile 109 can be between 150 and 180°, and in the illustrated embodiment, it can be about 165°.

[0019] The cam 107 can have the smallest radius in the exhaust cam profile 109. Furthermore, the minimum radius of the exhaust cam profile can be the radius at the midpoint 111 of the exhaust cam profile 109.

[0020] The cam 107 can have the largest radius between the compression cam profile 110 and the combustion cam profile 108.

[0021] The radius of the compression cam profile 110 increases with the angle. Specifically, the maximum radius of the compression cam profile 110 can be the radius at the end 113 of the compression cam profile 110. Similarly, the minimum radius of the compression cam profile 110 can be the radius at the starting point 114 of the compression cam profile 110.

[0022] The radius of the compression cam profile 110 can increase linearly with the angle.

[0023] The combustion cam profile 108 may have a starting point 115 shaped to impart a greater tangential force vector component orthogonal to the radius of the cam 107 as compared to its end 116. That is, during combustion, the follower 106 imparts a greater tangential force vector component at the starting point 115 of the combustion cam profile 108, thereby maximizing the rotational force applied to the cam 107 at the starting point 115 of the combustion cam profile 108. The tangential force vector component may gradually decrease towards the end 116 of the combustion cam profile 108.

[0024] Each follower 106 may comprise a roller bearing that interacts with the cam 107.

[0025] As shown in FIG. 3, the follower 106 may be linearly guided within a guide rail 117. The guide rail 117 may be formed within a central plate 118. The central plate 119 may surround a part of the exhaust chamber 119, and the central plate 118 may have an exhaust opening 120 therethrough. In a preferred embodiment, the guide rails 117 are formed on both sides of each follower 116. That is, although FIG. 3 shows only the guide rail on one side of the follower, in an embodiment, the guide rails 117 are also provided on both sides of the follower 116. In this regard, the guide rails 117 may be formed by adjacent side plates or the like, such that the follower 106 is evenly guided on both sides by the guide rails 117.

[0026] During the exhaust stroke, the head 104 of the piston 102 moves beyond the side exhaust port 122 of the cylinder 103, thereby enabling gas exhaust into the exhaust chamber 119.

[0027] The exhaust port 122 may be designed to define an opening proportional to the piston offset. For example, in the embodiment shown in FIG. 1, the side exhaust port 112 has a substantially triangular cross-section. However, in the embodiment shown in FIG. 2, the side exhaust port 112 has a substantially semi-circular cross-section.

[0028] The piston assembly 101 is kept in balance at an angle with respect to the radius from the drive shaft 121. In the illustrated embodiment, the piston assembly 101 is at an angle of approximately 3° in the rotational direction.

[0029] The engine 100 may further include an intake manifold 123 that interacts with the cylinder 103. In an embodiment, compressed air is turbo-injected into the manifold 123. The manifold 123 may be defined between an outer cylindrical section and an inner cylindrical section 125.

[0030] The valve may interact with the cylinder 103 and the manifold 123. The valve may be configured to close under compression during the compression stroke and, in this regard, may take the form of a reed valve. However, when not under compression, the valve can open, thereby allowing pressurized air from the manifold 123 to pass through the cylinder 103.

[0031] The engine 100 may further include a fuel injector 126 that injects fuel into the cylinder 103. The fuel injector 126 may be timed to inject fuel near the top dead center position of the piston 102, for example, when the follower 106 is between the compression cam profile 110 and the combustion cam profile 108. The timing of the fuel injector may be operably coupled to depend on the rotational position of the cam 107.

[0032] Referring to FIG. 4, the engine 100 may be housed within a substantially cylindrical housing. The housing may include an air intake 127 that communicates with the manifold 123.

[0033] The engine 100 may be operated with diesel, gasoline, vegetable oil, biofuel, or hydrogen.

[0034] At the starting point 114 of the compression cam profile, the piston 102 enters the cylinder 103, thereby causing compression. As suggested above, the cylinder valve can be closed to seal the cylinder 103 under pressure or by a timing mechanism coupled to the rotational position of the cam 107.

[0035] Near the top dead center position of the piston 102 (i.e., between the compression cam profile 110 and the combustion cam profile 108), fuel can be injected into the cylinder 103 by the fuel injector 126. Preferably, no spark plug is required to ignite the air-fuel mixture under compression.

[0036] Ignition is timed such that the follower 106 of the piston 102 is exactly at the starting point 115 of the combustion cam profile 108. As suggested above, the shape of the starting point 115 of the combustion cam profile 108 imparts a larger tangential force vector component, thereby increasing the rotational force applied to the cam 107.

[0037] The piston 102 exits the cylinder 103 while applying a rotational force to the combustion cam profile 108.

[0038] When the follower 106 moves into the exhaust cam profile 109, the piston head 104 moves past the side exhaust port 122, thereby allowing the spent gas to leak into the exhaust chamber 119 of the engine 100. Compressed air in the manifold 123 can flush the cylinder 103 with fresh air for the next compression and combustion strokes.

[0039] In an embodiment, the engine 100 operates with a dual fuel mixture. The dual fuel mixture can include a mixture of gasoline and diesel. In this regard, the engine 100 can include a dual fuel injector 126 for each cylinder 103.

[0040] In an embodiment, these dual fuel injectors 126 can be operated at different timings. For example, the gasoline fuel injector 126 injects gasoline at the start of the compression stroke, and the diesel fuel injector 126 injects diesel later, near the end of the compression stroke. The compression of the diesel fuel ignites the diesel fuel, which in turn can ignite the gasoline-air mixture simultaneously.

[0041] In an embodiment, the piston assembly 101 is electromagnetic. In this regard, the outer end of each cylinder 103 can include an electromagnet controlled by an electronic timing circuit to repel the head 104 of the piston 102. The head of the piston 102 can include a permanent magnet inside to increase the magnetic force applied by the electromagnet.

[0042] In an embodiment, the electromagnet can be controlled to be on or off. However, in a preferred embodiment, the current applied to the electromagnet can be controlled to proportionally control the force applied to the piston 102 according to the rotational position of the cam 107. Thus, for example, the maximum current can be applied at the start of the "combustion" cam profile 108 and gradually decrease towards its end.

[0043] This arrangement of the electromagnetic piston can overcome the back electromotive force / back EMF received by a conventional electric motor.

[0044] FIG. 5 shows an embodiment in which the engine 100 includes a flywheel 128 having a central opening 130 for the drive shaft 121, whereby the flywheel 128 rotates with the drive shaft 121.

[0045] The flywheel 128 includes an eccentric guide 129 configured to retract the follower 106 with respect to the cam 107. The eccentric guide 129 is eccentric with respect to the drive shaft 121.

[0046] In the illustrated embodiment, the eccentric guide 129 is a rail protruding from the backstop plate 131. However, in an alternative embodiment, the eccentric guide 129 may be embedded within the backstop plate 131.

[0047] In an embodiment, the eccentric guide 129 surrounds the roller bearing of the follower 106, the cam 107 pushes the roller bearing outward to move the follower 106 outward, and the eccentric guide 129 pulls the roller bearing inward to retract the follower 106.

[0048] In the illustrated embodiment, the eccentric guide 129 is circular. However, in an alternative embodiment, the eccentric guide 129 has a profile that matches the profile of the cam 107, such that the follower 106 closely follows the profile of the cam 107.

[0049] The eccentric guide 129 may retract the follower 106 during the intake stroke, thereby eliminating the need for turbo injection in the intake manifold 123 and enabling the four-stroke cycle operation of the engine 100.

[0050] The flywheel 128 may have a counterweight portion 132 for balancing the flywheel 128.

[0051] Figures 5 and 7 show a cam 107 having a geometry that is slightly different from that shown in Figure 1, particularly with respect to a flatter combustion cam profile 108 designed to cooperate with the flywheel 128 for two-stroke or four-stroke operation.

[0052] The foregoing description has employed specific technical terms for the convenience of explanation so as to enable a complete understanding of the present invention. However, it will be apparent to those skilled in the art that specific details are not necessary for practicing the present invention. Therefore, the foregoing description of specific embodiments of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise forms disclosed, as will be apparent that many modifications and variations are possible in light of the above teachings. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and thus to enable others skilled in the art to best utilize the present invention and various embodiments with various modifications suitable for the particular uses contemplated. It is intended that the following claims and their equivalents define the scope of the present invention.

Claims

1. A radial cam engine comprising a radially arranged piston assembly having a piston reciprocating within an internal combustion cylinder and a guide follower operably interacting with a central cam that rotates a drive shaft, wherein the cam comprises three different cam profiles for a compression stroke, a combustion stroke, and an exhaust stroke.

2. The engine according to claim 1, wherein the angle of the combustion cam profile is approximately half of the angle of the compression cam profile.

3. The engine according to claim 1, wherein the angle of the combustion cam profile is greater than the angle of the compression cam profile.

4. The engine according to claim 1, wherein the combustion cam profile is between 50 and 80°.

5. The engine according to claim 4, wherein the combustion cam profile is approximately 64.5°.

6. The engine according to claim 1, wherein the compression cam profile is between 110 and 150°.

7. The engine according to claim 6, wherein the compression cam profile is approximately 130°.

8. The engine according to claim 1, wherein the exhaust cam profile is between 150 and 180°.

9. The engine according to claim 8, wherein the exhaust cam profile is approximately 165°.

10. The engine according to claim 1, wherein the smallest radius of the cam is the radius in the exhaust cam profile.

11. The engine according to claim 1, wherein the maximum radius of the cam is the radius between the compression cam profile and the combustion cam profile.

12. The engine according to claim 1, wherein the minimum radius of the exhaust cam profile is the radius at the middle of the exhaust device cam profile.

13. The engine according to claim 1, wherein the maximum radius of the compression cam profile is the radius at the end point of the compression cam profile.

14. The engine according to claim 1, wherein the minimum radius of the compression cam profile is the radius at the starting point of the compression cam profile.

15. The engine according to claim 1, wherein the compression cam profile has a radius that linearly increases with the angle.

16. The engine according to claim 1, wherein the combustion cam profile has a starting point shaped to impart a larger force vector component perpendicular to the radius of the cam compared to its end.

17. The engine according to claim 1, wherein each follower comprises a roller bearing.

18. The engine according to claim 1, wherein the follower is guided within a guide rail.

19. The engine according to claim 1, wherein during the exhaust stroke, the piston moves beyond the side exhaust port of the cylinder.

20. The engine according to claim 19, wherein the exhaust port is shaped to define an opening proportional to the piston offset.

21. The engine according to claim 1, wherein the piston assembly makes an angle with respect to the radius from the drive shaft in the rotational direction.

22. The engine according to claim 21, wherein the piston assembly makes an angle of about 3° with respect to the drive shaft.

23. The engine according to claim 1, further comprising an intake manifold that interacts with the cylinder of the piston assembly.

24. The engine according to claim 23, wherein compressed air is turbo-injected into the manifold.

25. The engine according to claim 24, wherein the manifold is defined between an outer cylindrical section and an inner cylindrical section.

26. The engine according to claim 22, further comprising a valve between the cylinder and the manifold.

27. The engine according to claim 26, wherein the valve closes during the compression stroke of the piston.

28. The engine according to claim 26, wherein the valve opens during the exhaust stroke of the piston.

29. The engine according to claim 1, further comprising a fuel injector that interacts with the cylinder.

30. The engine according to claim 29, wherein the fuel injector is timed to inject fuel substantially at the top dead center position of the piston.

31. The engine according to claim 1, comprising three piston assemblies.

32. The engine according to claim 1, wherein the engine operates with a binary fuel mixture.

33. The engine according to claim 32, wherein the binary fuel mixture includes a mixture of gasoline and diesel.

34. The engine according to claim 32, wherein the engine includes a dual fuel injector for each cylinder.

35. The engine according to claim 34, wherein one of the dual fuel injectors operates at a different timing, one fuel injector injects a first type of fuel at the start of the compression stroke, and the other fuel injector injects a second type of fuel near the end of the compression stroke.

36. The engine according to claim 35, wherein the first type of fuel includes gasoline and the second type of fuel includes diesel.

37. The engine according to claim 1, wherein the engine includes a flywheel having an eccentric guide configured to retract the follower.

38. The engine according to claim 37, wherein the eccentric guide surrounds a roller bearing of the follower.

39. The engine according to claim 37, wherein the eccentric guide is circular.

40. The engine according to claim 37, wherein the eccentric guide has a profile that matches the profile of the cam, so that the follower closely follows the profile of the cam.

41. The engine according to claim 37, wherein the engine is configured to operate in a four-stroke cycle.

42. The engine according to claim 37, wherein the flywheel has a counterweight portion for balancing the flywheel.

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