Claims
- 1. A valve train in an engine comprising:
a valve; a cam; at least one coupling component; a hydraulic lifter having a nominal length and coupled at least indirectly between the valve and the cam by way of the at least one coupling component; and a mechanism for varying the nominal length of the hydraulic lifter so that the nominal length is substantially closer to a minimum length of the hydraulic lifter than to a maximum length of the hydraulic lifter.
- 2. The valve train of claim 1, wherein the nominal length is equal to the minimum length plus up to one-third of a difference between the minimum length and the maximum length.
- 3. The valve train of claim 2, wherein the nominal length is equal to the minimum length plus one of 3%, 10% and 20% of the difference between the minimum and maximum lengths.
- 4. The valve train of claim 1, wherein the at least one coupling component includes a push rod.
- 5. The valve train of claim 4, wherein the at least one coupling component further includes a rocker arm.
- 6. The valve train of claim 5, wherein the valve includes a valve stem, wherein an end of the valve stem abuts a first end of the rocker arm, wherein a first end of the push rod abuts a second end of the rocker arm, and wherein a second end of the push rod abuts a first end of the hydraulic lifter, a second end of the hydraulic lifter being in contact with the cam.
- 7. The valve train of claim 5, wherein the mechanism includes at least one of an adjustment nut and a set screw that can be varied in position so as to vary a position of the rocker arm and thus further vary a position of the push rod, causing the nominal position of the hydraulic lifter to be varied.
- 8. The valve train of claim 4, wherein the mechanism includes a device capable of varying a length of the push rod.
- 9. The valve train of claim 1, wherein the cam includes an automatic compression release mechanism by which a shape of a perimeter of the cam can be varied.
- 10. An internal combustion engine comprising:
a crankcase; a crankshaft supported by the crankcase; a camshaft having a cam, wherein the camshaft is supported by the crankcase and is rotationally coupled to the crankshaft so that rotation of the crankshaft causes rotation of the camshaft; a valve; at least one component coupling the valve to the cam, wherein the at least one component includes a hydraulic lifter; and a mechanism for adjusting a nominal position associated with the hydraulic lifter so that the nominal position is closer to a first position at which the hydraulic lifter is at a minimum length than to a second position at which the hydraulic lifter is at a maximum length.
- 11. The internal combustion engine of claim 10, wherein the at least one component further includes at least one of a push rod and a rocker arm.
- 12. The internal combustion engine of claim 11, wherein the mechanism includes at least one of an adjustment nut and a set screw that is capable of adjusting a position of the rocker arm in relation to the crankcase, which in turn adjusts the nominal position of the hydraulic lifter.
- 13. The internal combustion engine of claim 11, wherein the mechanism includes a device that is capable of adjusting a length of the push rod.
- 14. The internal combustion engine of claim 10, wherein the cam includes a means for providing automatic compression release functionality.
- 15. The internal combustion engine of claim 10, wherein the mechanism adjusts the nominal position to be at no more than one-third of a distance from the first position to the second position.
- 16. The internal combustion engine of claim 15, wherein the mechanism adjusts the nominal position to be at one of 10% and 20% of the distance.
- 17. A method of configuring a hydraulic lifter of an internal combustion engine, the method comprising:
providing a valve train including the hydraulic lifter, wherein the valve train couples a cam of the engine to a valve of the engine at least indirectly by way of the hydraulic lifter; and adjusting at least one component of the valve train to set a nominal length of the hydraulic lifter so that the nominal length is substantially closer to a minimum length of the hydraulic lifter than a maximum length of the hydraulic lifter.
- 18. The method of claim 17, wherein the nominal length is set to be equal to the minimum length plus up to one-third of a difference between the minimum length and the maximum length.
- 19. The method of claim 18, wherein the nominal length is equal to the minimum length plus one of 3%, 10% and 20% of the difference between the minimum and maximum lengths.
- 20. The method of claim 18, further comprising:
readjusting the nominal position of the hydraulic lifter at a later time.
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a utility patent application which is based on and claims the benefit of U.S. provisional patent application 60/452,778 filed Mar. 7, 2003 and entitled “Adjustable Valve Train With Hydraulic Lifters”.
Provisional Applications (1)
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Number |
Date |
Country |
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60452778 |
Mar 2003 |
US |