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An improved apparatus for generating a variable compression ratio within an ICE includes a piston-in-piston assembly having an inner piston that is slidably mounted within an outer piston and coupled to an actuator. The actuator is further coupled to a fluid source, and a volume of fluid is selectiv

An improved apparatus for generating a variable compression ratio within an ICE includes a piston-in-piston assembly having an inner piston that is slidably mounted within an outer piston and coupled to an actuator. The actuator is further coupled to a fluid source, and a volume of fluid is selectively channeled into and out of the actuator to move the inner piston to selected positions corresponding to desired compression ratios. At top dead center, a top face of the outer piston maintains a substantially constant distance from an engine head assembly to minimize squish area variations.

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1. A piston assembly positionable in an internal combustion engine, the piston assembly comprising:an outer piston;an inner piston having a combustion surface;an actuator coupled to the inner piston; andwherein the inner piston is slidably mounted within the outer piston and selectively moveable by

1. A piston assembly positionable in an internal combustion engine, the piston assembly comprising:an outer piston;an inner piston having a combustion surface;an actuator coupled to the inner piston; andwherein the inner piston is slidably mounted within the outer piston and selectively moveable by the actuator, and the outer piston and the actuator are directly attached to the wrist pin. 2. A method of generating a variable compression ratio in an internal combustion engine comprising:selectively sliding an inner piston within an outer piston;positioning a top surface of the inner piston at a first position;channeling fluid into an actuator coupled to the inner piston to move the inner piston to a second position wherein the top surface at the second position is lower than the top surface at the first position;sending a first command signal to a control valve coupled to a fluid source to start a flow of fluid, thereby moving the inner piston to the second position; andsending a second command signal to the control valve to stop the flow of fluid, thereby moving the inner piston to the first position. 3. A piston assembly positionable in an internal combustion engine, the piston assembly comprising an inner piston and an outer piston, the inner piston being slidably mounted within the outer piston and selectively moveable by an actuator comprising a cam coupled to a spring, the spring biasing the inner piston in a first position. 4. A piston assembly positionable in an internal combustion engine, the piston assembly comprising an inner piston and an outer piston, the inner piston being slidably mounted within the outer piston and selectively moveable by an actuator comprising a cam having a plurality of bearing surfaces, the cam being coupled to the inner piston and the inner piston being selectively supported by the bearing surfaces as the cam rotates. 5. A piston assembly positionable in an internal combustion engine, the piston assembly comprising an inner piston and an outer piston, the inner piston being slidably mounted within the outer piston and selectively moveable by a cam coupled to the inner piston and to a hydraulic chamber, a volume of fluid being selectively channeled into the chamber to rotate the cam in a first direction to move the inner piston to a second position and selectively removed from the chamber to rotate the cam in a second direction to allow the inner piston to return to a first position. 6. A piston assembly positionable in an internal combustion engine comprising:an outer piston;an inner piston slidably mounted within the outer piston and selectively moveable by an actuator comprising a hydraulic piston provided in a hydraulic chamber and coupled to the inner piston; anda fluid delivery system adapted to be coupled to a fluid source to selectively channel a volume of fluid into the actuator to move the inner piston to a first position and selectively remove the fluid from the actuator to move the inner piston to a second position, the volume of fluid displacing the hydraulic piston to move the inner piston and thereby actuate the inner piston. 7. An apparatus for generating a variable compression ratio in an internal combustion engine comprising:an outer piston;an inner piston slidably mounted within the outer piston;a wrist pin rigidly embedded in the outer piston;a cam assembly pivotably mounted on the wrist pin and coupled to the inner piston, the cam assembly selectively moving the inner piston to a desired position within the outer piston; andwherein a distance between a top surface of the outer piston and a bottom surface of a cylinder head when the piston assembly is positioned at top dead center remains substantially constant, independent of a location of the inner piston. 8. A method of generating a variable compression ratio in an internal combustion engine comprising:positioning an inner piston in a first position within an outer piston, the inner and the outer piston being placed wi thin a cylinder of an internal combustion engine, the inner and the outer piston compressing a first volume of air within the cylinder, the first position causing the cylinder to function at a first compression ratio;selectively moving the inner piston to a second position within the outer piston, the inner and the outer piston compressing a second volume of air within the cylinder, the second position causing the cylinder to function at a second compression ratio; andselectively channeling a volume of fluid into and out of an actuator coupled to the inner piston to move the inner piston. 9. A piston assembly positionable in an internal combustion engine, the piston assembly comprising:an outer piston;an inner piston having a combustion surface;an actuator comprising a cam coupled to a spring; andwherein the actuator is coupled to the inner piston, the inner piston is slidably mounted within the outer piston and selectively moveable by the actuator, and the spring is coupled to the inner piston to bias the inner piston in a first position. 10. The piston assembly according to claim 9 wherein the spring is a clock spring having a first end affixed to a wrist pin, the wrist pin being coupled to the outer piston. 11. The piston assembly according to claim 9 wherein the spring is a coil spring pivotably attached to the cam. 12. A piston assembly positionable in an internal combustion engine, the piston assembly comprising:an outer piston;an inner piston having a combustion surface;an actuator comprising a cam having a plurality of bearing surfaces; andwherein the actuator is coupled to the inner piston the inner piston is slidably mounted within the outer piston and selectively moveable by the actuator, and the inner piston is selectively supported by the bearing surfaces as the cam rotates. 13. The piston assembly according to claim 12 wherein the cam is coupled to a hydraulic chamber, a volume of fluid being selectively channeled into the chamber to rotate the cam in a first direction to move the inner piston to a second position, and selectively removed from the chamber to rotate the cam in a second direction to allow the inner piston to return to a first position. 14. The piston assembly according to claim 13 wherein the cam is further coupled to a spring to bias the inner piston in the first position. 15. A method of generating a variable compression ratio in an internal combustion engine comprising:positioning an inner piston in a first position within an outer piston, the inner and the outer piston being placed within a cylinder of an internal combustion engine, the inner and the outer piston compressing a first volume of air within the cylinder, the first position causing the cylinder to function at a first compression ratio;holding the inner piston substantially in the first position;monitoring operating conditions of the internal combustion engine;selectively moving the inner piston to a second position within the outer piston at a selected point in time, the inner and the outer piston compressing a second volume of air within the cylinder, the second position causing the cylinder to function at a second compression ratio; andselectively holding the inner piston substantially in the second position. 16. The method according to claim 15 further comprising:selectively channeling a volume of fluid into and out of an actuator coupled to the inner piston to move the inner piston. 17. The method according to claim 15 further comprising:monitoring the pressure of the cylinder;comparing a pressure generated by the inner piston at the first position to a desirable maximum cylinder pressure; andmoving the inner piston to change the compression ratio of the cylinder as needed to maximize the compression ratio generated by the engine without exceeding the desired maximum cylinder pressure. 18. The method according to claim 15 further comprising:monitoring the power demanded;comparing the power demand to a desirable maximum power out put for a compression ratio; andmoving the inner piston to change the compression ratio of the cylinder as needed to maximize the compression ratio generated by the engine without exceeding the desired maximum power output. 19. A piston assembly positionable in an internal combustion engine, the piston assembly comprising:an outer piston; an inner piston having a combustion surface;an actuator coupled to the inner piston and to a fluid source; andwherein the inner piston is slidably mounted within the outer piston and selectively moveable by the actuator, and a volume of fluid is selectively channeled into the actuator to move the inner piston to a second position and selectively removed from the actuator to allow the inner piston to move to a first position. 20. The piston assembly according to claim 19 wherein a spring is coupled to the inner piston to bias the inner piston to the first position. 21. The piston assembly according to claim 19 wherein a top surface of the inner piston is substantially adjacent to a top surface of the outer piston when the inner piston is in the first position, and below the top surface of the outer piston when the inner piston is in the second position. 22. The piston assembly according to claim 19 wherein a bottom surface of the inner piston rests upon a first flat portion of the actuator when the inner piston is in the first position and upon a second flat portion of the actuator when the inner piston is in the second position. 23. The piston assembly according to claim 19 wherein the actuator is coupled to a connecting rod and the fluid is channeled into the actuator via a fluid delivery system coupled to a bore provided in the connecting rod. 24. The piston assembly according to claim 19 wherein movement of the inner piston is continuously variable. 25. The piston assembly according to claim 19 wherein movement of the inner piston is intermittently variable. 26. The piston assembly according to claim 19 wherein a piston bowl is provided within the inner piston. 27. A piston assembly positionable in an internal combustion engine comprising:an outer piston;an inner piston slidably mounted within the outer piston and selectively moveable by an actuator coupled to the inner piston; anda fluid delivery system adapted to be coupled to a fluid source to selectively channel a volume of fluid into the actuator to move the inner piston to a first position and selectively remove the fluid from the actuator to move the inner piston to a second position, thereby actuating the inner piston. 28. The piston assembly according to claim 27 wherein the fluid is engine oil. 29. The piston assembly according to claim 27 wherein the fluid is hydraulic fluid. 30. The piston assembly according to claim 27 wherein the actuator comprises a cam assembly and a hydraulic chamber. 31. The piston assembly according to claim 30 wherein the cam assembly is directly attached to a wrist pin, the wrist pin being integral with the hydraulic chamber and coupled to the outer piston. 32. The piston assembly according to claim 30 wherein the cam assembly is directly attached to a wrist pin and the hydraulic chamber is external to the wrist pin. 33. The piston assembly according to claim 27 wherein the actuator comprises a cam coupled to the inner piston, to a wrist pin and to a connecting rod, the cam being coupled to a hydraulic chamber provided in the wrist pin, and the fluid delivery system includes a bore extending through the connecting rod, the bore being in fluid communication with the hydraulic chamber. 34. The piston assembly according to claim 33 wherein a fluid entry port provided in the wrist pin has a sufficient width to maintain fluid communication with the connecting rod bore as the connecting rod rotates about the wrist pin. 35. The piston assembly according to claim 33 wherein a hydraulic piston coupled to the cam extends into the hydraulic chamber, the volume of fluid selectively flowing into the hydraulic chamb er to displace the hydraulic piston to move the cam and the inner piston. 36. The piston assembly according to claim 27 wherein the actuator comprises a hydraulic piston provided in a hydraulic chamber and coupled to the inner piston, the volume of fluid displacing the hydraulic piston to move the inner piston. 37. The piston assembly according to claim 26 wherein the hydraulic piston is provided with a bore to provide a path of fluid communication between the source of fluid and the hydraulic chamber. 38. The piston assembly according to claim 36 wherein the hydraulic chamber has a first region and a second region on either side of a head of the hydraulic piston and a stem having a first bore and a second bore, the first bore being in fluid communication with the first region and the second bore being in fluid communication with the second region. 39. An apparatus for generating a variable compression ratio in an internal combustion engine comprising:an outer piston;an inner piston slidably mounted within the outer piston;a wrist pin rigidly embedded in the outer piston;a cam assembly pivotably mounted on the wrist pin and coupled to the inner piston;a control system that monitors operating conditions and selectively generates a command signal; andwherein the cam assembly selectively moves the inner piston to a desired position within the outer piston in response to the command signal. 40. The apparatus according to claim 39 wherein a piston bowl is provided in the inner piston. 41. The apparatus according to claim 39 wherein movement of the inner piston is continuously variable. 42. The apparatus according to claim 39 wherein movement of the inner piston is intermittently variable. 43. The apparatus according to claim 39 wherein a distance between a top surface of the outer piston and a bottom surface of a cylinder head when the piston assembly is positioned at top dead center remains substantially constant, independent of a location of the inner piston. 44. The apparatus according to claim 39 wherein a top surface of the inner piston is substantially adjacent with a top surface of the outer piston when the inner piston is in a first position, and the top surface of the inner piston is below the top surface of the outer piston when the inner piston is in a second position. 45. The apparatus according to claim 39 wherein the cam assembly further comprises a clock spring to bias the inner piston in a first position, the clock spring having a first end affixed to the wrist pin. 46. The apparatus according to claim 39 wherein the cam assembly further comprises a coil spring to bias the inner piston in a first position, the coil spring being pivotably attached to the cam assembly. 47. The apparatus according to claim 39 wherein the cam assembly is coupled to a hydraulic chamber, the hydraulic chamber being coupled to a fluid source and a volume of fluid being selectively channeled into the chamber to actuate the cam assembly to move the inner piston to a second position, the volume of fluid being selectively removed from the chamber to allow the cam assembly and the inner piston to return to a first position. 48. The apparatus according to claim 47 wherein the cam assembly comprises a spring to bias the inner piston in a first position and a hydraulic piston is provided in the hydraulic chamber, displacement of the hydraulic piston actuating the cam assembly. 49. The apparatus according to claim 47 wherein the hydraulic chamber is integral to the wrist pin. 50. The apparatus according to claim 47 wherein the hydraulic chamber is external to the wrist pin. 51. The apparatus according to claim 50 wherein the hydraulic chamber has a first region and a second region on either side of a head of the hydraulic piston and a stem having a first bore and a second bore, the first bore being in fluid communication with the first region and the second bore being in fluid communication with the second region. 52. An internal combustion engine having a variable compression ratio comprising:an outer piston;an inner piston slidably mounted within the outer piston;a wrist pin rigidly embedded in the outer piston;a cam assembly coupled to the wrist pin and the inner piston to selectively move the inner piston within the outer piston from a first position to a second position; anda fluid delivery system coupled to the cam assembly, wherein a volume of fluid is selectively channeled to and from the cam assembly to move the inner piston from the first position to the second position. 53. The internal combustion engine of claim 52 wherein the fluid is engine oil. 54. The internal combustion engine of claim 52 wherein the fluid is a hydraulic fluid. 55. The internal combustion engine of claim 52 further comprising a spring coupled to the cam assembly to bias the inner piston in the first position. 56. The internal combustion engine of claim 52 further comprising a command signal to activate the flow of fluid to the cam assembly. 57. The internal combustion engine according to claim 52 wherein movement of the inner piston is continuously variable. 58. The internal combustion engine according to claim 52 wherein movement of the inner piston is intermittently variable. 59. The internal combustion engine according to claim 52 wherein a distance between a top surface of the outer piston and a bottom surface of a cylinder head when the outer piston is positioned at top dead center remains substantially constant, independent of a location of the inner piston. 60. The internal combustion engine according to claim 52 wherein a top surface of the inner piston is substantially adjacent with a top surface of the outer piston when the inner piston is in a first position, and the top surface of the inner piston is below the top surface of the outer piston when the inner piston is in a second position. 61. The internal combustion engine according to claim 52 wherein a piston bowl is provided within the inner piston.