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A valve assembly for an internal combustion engine includes a stationary permanent magnet assembly having at least one permanent magnet for generating a permanent magnetic field with a radial component and a movable coil assembly having at least one coil of electrically conductive material for gener

A valve assembly for an internal combustion engine includes a stationary permanent magnet assembly having at least one permanent magnet for generating a permanent magnetic field with a radial component and a movable coil assembly having at least one coil of electrically conductive material for generating a magnetic field with an axial component that intersects the radial component when an electrical current is applied to the at least one coil to thereby move the coil assembly with respect to the permanent magnet assembly. A valve is connected to the coil assembly for movement therewith. Electronic control of the valve assembly together with engine modifications permits the engine to dynamically switch between two-cycle and four-cycle modes of operation.

대표청구항 ▼

What is claimed is: 1. A linear actuator comprising: a stationary permanent magnet assembly having at least one permanent magnet for generating a permanent magnetic field with a radial component; and a movable coil assembly having at least one coil of electrically conductive material for generating

What is claimed is: 1. A linear actuator comprising: a stationary permanent magnet assembly having at least one permanent magnet for generating a permanent magnetic field with a radial component; and a movable coil assembly having at least one coil of electrically conductive material for generating a temporary magnetic field with an axial component that intersects the radial component when an electrical current is applied to the at least one coil to thereby move the coil assembly with respect to the permanent magnet assembly, the movable coil assembly comprising a spool on which the at least one coil is wound, the permanent magnet assembly being located within the spool. 2. A linear actuator according to claim 1, wherein the spool is constructed of a non-ferromagnetic material. 3. A linear actuator according to claim 1, wherein alternating electrical current applied to the at least one coil causes reciprocal axial movement of the coil assembly. 4. A linear actuator according to claim 1, wherein the permanent magnet assembly comprises at least one stack of a plurality of permanent magnets. 5. A linear actuator comprising: a stationary permanent magnet assembly having a plurality of stacks, each stack comprising a plurality of axially oriented permanent magnets that are magnetically attracted together for generating a permanent magnetic field with a radial component; and a movable coil assembly having at least one coil of electrically conductive material for generating a temporary magnetic field with an axial component that intersects the radial component when an electrical current is applied to the at least one coil to thereby move the coil assembly with respect to the permanent magnet assembly. 6. A linear actuator according to claim 5, wherein each stack is oriented to be axially repulsed from an adjacent stack. 7. A linear actuator according to claim 6, wherein each stack is separated from an adjacent stack by a ferromagnetic spacer. 8. A linear actuator according to claim 6, wherein the radial component of the permanent magnetic field is generated between the repulsed adjacent stacks. 9. A linear actuator according to claim 8, wherein the movable coil assembly comprises a spool on which the at least one coil is wound, at least a portion of the permanent magnet assembly being located in the spool. 10. A linear actuator according to claim 9, and further comprising a stationary housing extending around the permanent magnet assembly with an air gap formed therebetween, the housing being constructed of ferromagnetic material such that a permanent magnetic circuit is formed between adjacent stacks and the housing with the radial component of the permanent magnetic field passing through the air gap. 11. A linear actuator according to claim 10, wherein the spool and the at least one coil are located in the air gap for reciprocal movement. 12. A linear actuator according to claim 11, wherein the movable coil assembly comprises a plurality of spaced coils of electrically conductive material, with adjacent coils being wrapped around the spool in opposite directions to form opposite magnetic fields when electrical current is applied thereto. 13. A linear actuator according to claim 12, wherein alternating electrical current applied to the plurality of coils causes reciprocal axial movement of the coil assembly. 14. An electronic valve assembly comprising the linear actuator of claim 13 for an internal combustion engine having a combustion chamber with a valve seat, the electronic valve assembly further comprising a valve having a valve stem with one end connected to the movable coil assembly and a valve head connected to an opposite end of the valve stem, the valve being movable with the coil assembly between a closed position wherein the valve head is adapted for contacting the valve seat and an open position wherein the valve head is spaced from the valve seat. 15. An electronic valve assembly according to claim 14, wherein the valve is in the open position in the absence of electric current to the plurality of coils. 16. An internal combustion engine comprising at least two electronic valve assemblies according to claim 14, the internal combustion engine further comprising: an engine block having a cylinder formed therein; a piston having a piston head for reciprocal movement in the cylinder; and a cylinder head connected to the engine block and having a primary intake port and a primary exhaust port, with one of the electronic valve assemblies being operable to open and close the primary intake port and the other of the electronic valve assemblies being operable to open and close the primary exhaust port. 17. An internal combustion engine according to claim 16, and further comprising a secondary exhaust port located at a predetermined position in the cylinder such that when the piston head is above the predetermined position the secondary exhaust port is closed and when the piston head is below the predetermined position the secondary exhaust port is open for expelling exhaust gases from the cylinder. 18. An internal combustion engine according to claim 17, wherein the valves are in the open position in the absence of electric current to the plurality of coils. 19. An internal combustion engine according to claim 17, and further comprising: an intake manifold with a primary intake conduit in fluid communication with the primary intake port; a primary exhaust manifold with a primary exhaust conduit in fluid communication with the primary exhaust port; and a secondary exhaust manifold in fluid communication with the secondary exhaust port. 20. An internal combustion engine according to claim 19, wherein the primary exhaust manifold further comprises a secondary intake conduit and a diverter valve operable between a first position to close the primary exhaust conduit and open the secondary intake conduit and a second position to open the primary exhaust conduit and close the secondary intake conduit such that the internal combustion engine can be switched between a four-cycle mode of operation and a two-cycle mode of operation. 21. An internal combustion engine according to claim 20, and further comprising an electrical actuator for moving the diverter valve between the first and second positions to thereby dynamically switch the internal combustion engine between the four-cycle and two-cycle modes of operation. 22. An electronic valve assembly comprising the linear actuator of claim 1 for an internal combustion engine having a combustion chamber with a valve seat, the electronic valve assembly further comprising a valve having a valve stem with one end connected to the movable coil assembly and a valve head connected to an opposite end of the valve stem, the valve being movable with the coil assembly between a closed position wherein the valve head is adapted for contacting the valve seat and an open position wherein the valve head is spaced from the valve seat. 23. An electronic valve assembly for an internal combustion engine having a combustion chamber with a valve seat, the electronic valve assembly comprising: a linear actuator including: a stationary permanent magnet assembly having at least one permanent magnet for generating a permanent magnetic field with a radial component; and a movable coil assembly having at least one coil of electrically conductive material for generating a temporary magnetic field with an axial component that intersects the radial component when an electrical current is applied to the at least one coil to thereby move the coil assembly with respect to the permanent magnet assembly; and a valve having a valve stem with one end connected to the movable coil assembly and a valve head connected to an opposite end of the valve stem, the valve being movable with the coil assembly between a closed position wherein the valve head is adapted for contacting the valve seat and an open position wherein the valve head is spaced from the valve seat; wherein the valve is in the open position in the absence of electric current to the at least one coil. 24. An internal combustion engine comprising at least two electronic valve assemblies according to claim 22, the internal combustion engine further comprising: an engine block having a cylinder formed therein; a piston having a piston head for reciprocal movement in the cylinder; and a cylinder head connected to the engine block and having a primary intake port and a primary exhaust port, with one of the electronic valve assemblies being operable to open and close the primary intake port and the other of the electronic valve assemblies being operable to open and close the primary exhaust port. 25. An internal combustion engine according to claim 24, and further comprising a secondary exhaust port located at a predetermined position in the cylinder such that when the piston head is above the predetermined position the secondary exhaust port is closed and when the piston head is below the predetermined position the secondary exhaust port is open for expelling exhaust gases from the cylinder. 26. An internal combustion engine according to claim 25, wherein the valves are in the open position in the absence of electric current to the at least one coil. 27. An internal combustion engine according to claim 25, and further comprising: an intake manifold with a primary intake conduit in fluid communication with the primary intake port; a primary exhaust manifold with a primary exhaust conduit in fluid communication with the primary exhaust port; and a secondary exhaust manifold in fluid communication with the secondary exhaust port. 28. An internal combustion engine according to claim 27, wherein the primary exhaust manifold further comprises a secondary intake conduit and a diverter valve operable between a first position to close the primary exhaust conduit and open the secondary intake conduit and a second position to open the primary exhaust conduit and close the secondary intake conduit such that the internal combustion engine can be switched between a four-cycle mode of operation and a two-cycle mode of operation. 29. An internal combustion engine according to claim 28, and further comprising an electrical actuator for moving the diverter valve between the first and second positions to thereby dynamically switch the internal combustion engine between the four-cycle and two-cycle modes of operation. 30. An internal combustion engine according to claim 24, and further comprising: a crankshaft positioned for rotation in the engine block; a connecting rod having one end pivotally connected to the piston head and an opposite end rotatably connected to the crankshaft; and a crank angle sensor positioned for detecting a rotational position of the crankshaft. 31. An internal combustion engine according to claim 30, and further comprising a control system for receiving a signal from the crank angle sensor and adjusting positions of the electronic valve assemblies based on the signal during operation of the internal combustion engine. 32. An internal combustion engine according to claim 31, wherein the signal is indicative of at least one of crankshaft rotation and crankshaft angle. 33. An internal combustion engine according to claim 31, wherein the electronic valve assemblies are in the open position in the absence of electrical power thereto. 34. An internal combustion engine according to claim 33, wherein the control system is operative to adjust an initial operating position of the electronic valve assemblies from the open position based on signals from the crank angle sensor during engine startup. 35. An internal combustion engine according to claim 31, wherein the control system comprises: a processor for receiving signals from the crank angle sensor and processing the signals to determine the positions of the electronic valve assemblies; valve control circuitry electrically connectable to the processor, the valve control circuitry being operable for receiving control signals from the processor for moving the valves of the electronic valve assemblies between the open and closed positions. 36. An internal combustion engine according to claim 35, wherein for each coil assembly, the valve control circuitry comprises: first and second transistor pairs operably connectable to the processor for receiving control signals therefrom; first and second MOSFET pairs electrically connectable between the first and second transistor pairs and first and second leads, respectively, of the at least one coil; wherein a logical high from the processor causes electrical current to pass through the at least one coil in one direction to thereby move the coil assembly toward one of the open and closed positions and a logical low from the processor causes electrical current to pass through the at least one coil in an opposite direction to thereby move the coil assembly toward the other of the open and closed positions. 37. A linear actuator comprising: a permanent magnet assembly having at least one permanent magnet for generating a permanent magnetic field with a radial component; and a coil assembly having at least one coil of electrically conductive material for generating a temporary magnetic field with an axial component that intersects the radial component when an electrical current is applied to the at least one coil to thereby move one of the magnet assembly and the coil assembly with respect to the other of the magnet assembly and the coil assembly, the coil assembly comprising a spool on which the at least one coil is wound, at least a portion of the permanent magnet assembly being located within the spool. 38. A linear actuator according to claim 37, wherein the permanent magnet assembly comprises a plurality of stacks, each stack comprising a plurality of axially oriented permanent magnets that are magnetically attracted together for generating the permanent magnetic field with the radial component. 39. A linear actuator according to claim 38, wherein each stack is oriented to be axially repulsed from an adjacent stack. 40. A linear actuator according to claim 39, wherein each stack is separated from an adjacent stack by a ferromagnetic spacer. 41. A linear actuator according to claim 39, wherein the radial component of the permanent magnetic field is generated between the repulsed adjacent stacks. 42. A linear actuator according to claim 41, and further comprising a stationary housing extending around the permanent magnet assembly with an air gap formed therebetween, the housing being constructed of ferromagnetic material such that a permanent magnetic circuit is formed between adjacent stacks and the housing with the radial component of the permanent magnetic field passing through the air gap. 43. A linear actuator according to claim 42, wherein the spool and the at least one coil are located in the air gap. 44. A linear actuator according to claim 43, wherein the coil assembly comprises a plurality of spaced coils of electrically conductive material, with adjacent coils being wrapped around the spool in opposite directions to form opposite magnetic fields when electrical current is applied thereto. 45. A linear actuator according to claim 44, wherein alternating electrical current applied to the plurality of coils causes reciprocal axial movement of one of the magnet assembly and coil assembly.