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Systems and methods for actuating engine valves are disclosed. The systems may include primary and auxiliary rocker arms disposed adjacent to each other on a rocker arm shaft. The primary rocker arm may actuate an engine valve for primary valve actuation motions, such as main exhaust events, in resp

Systems and methods for actuating engine valves are disclosed. The systems may include primary and auxiliary rocker arms disposed adjacent to each other on a rocker arm shaft. The primary rocker arm may actuate an engine valve for primary valve actuation motions, such as main exhaust events, in response to an input from a first valve train element, such as a cam. The auxiliary rocker arm may receive one or more auxiliary valve actuation motions, such as for engine braking, exhaust gas recirculation, and/or brake gas recirculation events, from a second valve train element. A hydraulic actuator piston may be disposed between the auxiliary rocker arm and the primary rocker arm. The actuator piston may be selectively locked into an extended position between the primary and auxiliary rocker arms so as to selectively transfer the one or more auxiliary valve actuation motions from the auxiliary rocker arm to the primary rocker arm.

대표청구항 ▼

What is claimed is: 1. A system for actuating an engine valve comprising: a rocker arm shaft; a means for imparting primary valve actuation motion; a primary rocker arm disposed on the rocker arm shaft, said primary rocker arm being adapted to actuate an engine valve and receive motion from the mea

What is claimed is: 1. A system for actuating an engine valve comprising: a rocker arm shaft; a means for imparting primary valve actuation motion; a primary rocker arm disposed on the rocker arm shaft, said primary rocker arm being adapted to actuate an engine valve and receive motion from the means for imparting primary valve actuation motion; a means for imparting auxiliary valve actuation motion; an auxiliary rocker arm disposed on the rocker arm shaft adjacent to the primary rocker arm, said auxiliary rocker arm having a first end adapted to receive motion from the means for imparting auxiliary valve actuation motion and a second end distal from the auxiliary rocker arm first end; a hydraulic actuator piston disposed between the second end of the auxiliary rocker arm and the primary rocker arm, said actuator piston being adapted to selectively transfer one or more auxiliary valve actuation motions from the auxiliary rocker arm to the primary rocker arm; and means for locking the hydraulic actuator piston in a fixed position relative to the auxiliary rocker arm or the primary rocker arm during a time that the auxiliary rocker arm receives motion from the means for imparting auxiliary valve actuation motion. 2. The system of claim 1 wherein the one or more auxiliary valve actuation motions are transferred from the primary rocker arm to the engine valve through a valve train element selected from the group consisting of: the valve, a valve bridge, and a pin. 3. The system of claim 1 further comprising an actuator bore formed in the primary rocker arm, wherein the actuator piston is disposed in the actuator bore. 4. The system of claim 3, the means for locking the hydraulic actuator piston comprising: a control valve bore formed in the primary rocker arm; a control valve piston disposed in the control valve bore; a first hydraulic fluid passage extending from the control valve bore to the actuator bore; and a second hydraulic fluid passage communicating with the control valve bore. 5. The system of claim 4 further comprising: a check valve disposed in the first hydraulic fluid passage; and a hydraulic fluid drain passage extending from the control valve bore to the actuator bore. 6. The system of claim 4 further comprising: a check valve disposed in the first hydraulic fluid passage; a protrusion extending from the control valve piston toward the check valve, said protrusion being adapted to selectively open the check valve; and a control valve spring biasing the control valve piston toward the check valve. 7. The system of claim 3 further comprising: a control valve bore formed in the primary rocker arm; a control valve piston disposed in the control valve bore; a first hydraulic fluid passage communicating with the control valve bore; a second hydraulic fluid passage extending from a hydraulic fluid supply to the actuator piston bore; a check valve disposed in the second hydraulic fluid passage; a pin extending from the control valve piston to the check valve, said pin being adapted to open the check valve; and a control valve spring biasing the control valve piston toward the check valve. 8. The system of claim 3 further comprising: a control valve bore formed in the primary rocker arm; a control valve piston disposed in the control valve bore; a first fluid passage extending from a control fluid source to the control valve bore; a second hydraulic fluid passage extending from the control valve bore to the actuator piston bore; a check valve disposed in the second hydraulic fluid passage; a third hydraulic fluid passage extending from a constant fluid supply to the control valve bore; a fourth hydraulic fluid passage extending from the control valve bore to the actuator piston bore; and a control valve spring biasing the control valve piston into the control valve bore, wherein the control valve piston is adapted to provide selective communication between (i) the first and second hydraulic fluid passages, and (ii) the third and fourth hydraulic fluid passages. 9. The system of claim 4 further comprising: a check valve disposed in the first hydraulic fluid passage; a protrusion extending from the control valve piston toward the check valve, said protrusion being adapted to selectively open the check valve; a control valve spring biasing the control valve piston toward the check valve; and a third hydraulic fluid passage communicating with a control valve spring side of the control valve, wherein the second hydraulic fluid passage communicates with a protrusion side of the control valve. 10. The system of claim 3 further comprising: a first control valve bore formed in the primary rocker arm; a first control valve piston disposed in the first control valve bore, said first control valve piston including a protrusion and having a protrusion side and a control side; a first fluid passage extending from a constant fluid supply to the first control valve bore on the protrusion side of the first control valve piston; a second hydraulic fluid passage extending from the first control valve bore to the actuator piston bore; a check valve disposed in the second hydraulic fluid passage; a second control valve bore; a second control valve piston disposed in the second control valve bore; a third hydraulic fluid passage extending from a control fluid source to the second control valve bore; a fourth hydraulic fluid passage extending from the constant fluid supply to the second control valve bore; a fifth hydraulic fluid passage extending from the second control valve bore as a hydraulic fluid drain; a sixth hydraulic fluid passage extending from the second control valve bore to the first control valve bore on the control side of the first control valve piston, wherein the second control valve piston is adapted to provide selective communication between (i) the fourth and sixth hydraulic fluid passages, and (ii) the fifth and sixth hydraulic fluid passages. 11. The system of claim 3 further comprising an actuator piston spring biasing the actuator piston into the actuator bore. 12. The system of claim 4 wherein the second hydraulic fluid passage extends through the primary rocker arm from the rocker shaft to the control valve bore. 13. The system of claim 4 further comprising a check valve incorporated into the control valve piston. 14. The system of claim 3 further comprising a means for biasing the auxiliary rocker arm toward the means for imparting auxiliary valve actuation motion. 15. The system of claim 14 wherein the means for biasing comprises a spring. 16. The system of claim 3 further comprising a means for biasing the auxiliary rocker arm toward the actuator piston. 17. The system of claim 16 wherein the means for biasing comprises a spring. 18. The system of claim 3 further comprising means for selectively locking the primary rocker arm and the auxiliary rocker arm together. 19. The system of claim 18, wherein no auxiliary valve actuation motion is imparted to the engine valve when the primary rocker arm and the auxiliary rocker arm are locked together. 20. The system of claim 18 wherein the means for selectively locking comprises a detent pin assembly. 21. The system of claim 3 wherein the actuator bore is formed in a boss formed near an end of the primary rocker arm. 22. The system of claim 3 further comprising means for biasing the actuator piston and the auxiliary rocker arm into contact with each other during a primary valve actuation mode of engine operation. 23. The system of claim 1, wherein the auxiliary valve actuation motion is selected from the group consisting of: engine braking motion, exhaust gas recirculation motion, auxiliary intake motion, and brake gas recirculation motion. 24. The system of claim 1 further comprising: an actuator bore formed in the second end of the auxiliary rocker arm, wherein the actuator piston is disposed in the actuator bore; and a flange extending from the primary rocker arm, said flange being adapted to contact the actuator piston. 25. The system of claim 24 further comprising: a control valve bore formed in the auxiliary rocker arm; a control valve piston disposed in the control valve bore; a first hydraulic fluid passage extending from the control valve bore to the actuator bore; and a second hydraulic fluid passage communicating with the control valve bore. 26. The system of claim 25 further comprising: a check valve disposed in the first hydraulic fluid passage; and a hydraulic fluid drain passage extending from the control valve bore to the actuator bore. 27. The system of claim 25 further comprising: a check valve disposed in the first hydraulic fluid passage; a protrusion extending from the control valve piston toward the check valve, said protrusion being adapted to selectively open the check valve; and a control valve spring biasing the control valve piston toward the check valve. 28. The system of claim 24 further comprising: a control valve bore formed in the auxiliary rocker arm; a control valve piston disposed in the control valve bore; a first hydraulic fluid passage communicating with the control valve bore; a second hydraulic fluid passage extending from a hydraulic fluid supply to the actuator piston bore; a check valve disposed in the second hydraulic fluid passage; a pin extending from the control valve piston to the check valve, said pin being adapted to open the check valve; and a control valve spring biasing the control valve piston toward the check valve. 29. The system of claim 24 further comprising: a control valve bore formed in the auxiliary rocker arm; a control valve piston disposed in the control valve bore; a first fluid passage extending from a control fluid source to the control valve bore; a second hydraulic fluid passage extending from the control valve bore to the actuator piston bore; a check valve disposed in the second hydraulic fluid passage; a third hydraulic fluid passage extending from a constant fluid supply to the control valve bore; a fourth hydraulic fluid passage extending from the control valve bore to the actuator piston bore; and a control valve spring biasing the control valve piston into the control valve bore, wherein the control valve piston is adapted to provide selective communication between (i) the first and second hydraulic fluid passages, and (ii) the third and fourth hydraulic fluid passages. 30. The system of claim 25 further comprising: a check valve disposed in the first hydraulic fluid passage; a protrusion extending from the control valve piston toward the check valve, said protrusion being adapted to selectively open the check valve; a control valve spring biasing the control valve piston toward the check valve; and a third hydraulic fluid passage communicating with a control valve spring side of the control valve, wherein the second hydraulic fluid passage communicates with a protrusion side of the control valve. 31. The system of claim 24 further comprising: a first control valve bore formed in the auxiliary rocker arm; a first control valve piston disposed in the first control valve bore, said first control valve piston including a protrusion and having a protrusion side and a control side; a first fluid passage extending from a constant fluid supply to the first control valve bore on the protrusion side of the first control valve piston; a second hydraulic fluid passage extending from the first control valve bore to the actuator piston bore; a check valve disposed in the second hydraulic fluid passage; a second control valve bore; a second control valve piston disposed in the second control valve bore; a third hydraulic fluid passage extending from a control fluid source to the second control valve bore; a fourth hydraulic fluid passage extending from the constant fluid supply to the second control valve bore; a fifth hydraulic fluid passage extending from the second control valve bore as a hydraulic fluid drain; a sixth hydraulic fluid passage extending from the second control valve bore to the first control valve bore on the control side of the first control valve piston, wherein the second control valve piston is adapted to provide selective communication between (i) the fourth and sixth hydraulic fluid passages, and (ii) the fifth and sixth hydraulic fluid passages. 32. The system of claim 24 further comprising an actuator piston spring biasing the actuator piston into the actuator bore. 33. The system of claim 25 wherein the second hydraulic fluid passage extends through the auxiliary rocker arm from the rocker shaft to the control valve bore. 34. The system of claim 25 further comprising a check valve incorporated into the control valve piston. 35. The system of claim 24 further comprising a means for biasing the auxiliary rocker arm toward the means for imparting auxiliary valve actuation motion. 36. The system of claim 35 wherein the means for biasing comprises a spring. 37. The system of claim 24 further comprising a means for biasing the auxiliary rocker arm toward the flange on the primary rocker arm. 38. The system of claim 37 wherein the means for biasing comprises a spring. 39. The system of claim 24 further comprising means for selectively locking the primary rocker arm and the auxiliary rocker arm together. 40. The system of claim 39 wherein the means for selectively locking comprises a detent pin assembly. 41. The system of claim 24 further comprising means for biasing the primary rocker arm and the actuator piston into contact with each other during a primary valve actuation mode of engine operation. 42. The system of claim 1 further comprising means for biasing the actuator piston into contact with the primary rocker arm during a primary valve actuation mode of engine operation. 43. The system of claim 3 further comprising means for adjusting a lash space between the actuator piston and the auxiliary rocker arm. 44. The system of claim 24 further comprising means for adjusting a lash space between the actuator piston and the primary rocker arm. 45. A method of actuating an engine valve for primary and auxiliary valve actuation events using a primary rocker arm, an auxiliary rocker arm, and a hydraulic actuator piston disposed between the ends of the primary and auxiliary rocker arms that are proximal to the engine valve, said method comprising the steps of: actuating the engine valve for a primary valve actuation event responsive to motion imparted from a first valve train element to the primary rocker arm during a primary valve actuation mode of engine operation; extending and locking the hydraulic actuator piston into a fixed position between the actuation ends of the primary and auxiliary rocker arms during a time that motion is imparted to the auxiliary rocker arm such that the hydraulic actuator piston provides selective contact between the primary and auxiliary rocker arms without the hydraulic actuator piston locking the primary and auxiliary rocker arms together; actuating the engine valve for one or more auxiliary valve actuation events responsive to motion imparted from a second valve train element to the auxiliary rocker arm during an auxiliary valve actuation mode of engine operation. 46. The method of claim 45 wherein the auxiliary valve actuation events are selected from the group consisting of: an exhaust gas recirculation event and a brake gas recirculation event. 47. The method of claim 45 wherein the engine valve comprises an intake valve. 48. A system for actuating an engine valve comprising: a rocker arm shaft; a first rocker arm disposed on the rocker arm shaft and having an end proximal to the engine valve; a means for imparting a first valve actuation motion to the first rocker arm; a second rocker arm disposed on the rocker arm shaft adjacent to the first rocker arm, said second rocker arm having an end proximal to the engine valve; a means for imparting one or more second valve actuation motions to the second rocker arm, said second valve actuation motions being selected from the group consisting of: engine braking motion, exhaust gas recirculation motion, main exhaust motion, main intake motion, auxiliary intake motion, and brake gas recirculation motion; a hydraulic actuator piston disposed between the ends of the second rocker arm and the first rocker arm that are proximal to the engine valve, said actuator piston having an axis extending in a direction substantially co-planar with a rotation direction of the first and second rocker arms; and a hydraulic fluid control valve disposed in either the first rocker arm or the second rocker arm, said control valve adapted to selectively control the position of the hydraulic actuator piston and lock the hydraulic actuator piston in a fixed position relative to the first rocker arm or the second rocker arm during a time that the second rocker arm receives motion from the means for imparting one or more second valve actuation motions. 49. The system of claim 48 wherein the hydraulic actuator piston is laterally offset from the first rocker arm in the direction of the second rocker arm. 50. The system of claim 48 wherein the hydraulic actuator piston is laterally offset from the second rocker arm in the direction of the first rocker arm. 51. The system of claim 48 wherein the first rocker arm is selected from the group consisting of an intake rocker arm, an exhaust rocker arm, and an auxiliary rocker arm. 52. The system of claim 48 wherein the one or more second valve actuation motions are transferred from the first rocker arm to the engine valve either directly or through a valve train element selected from the group consisting of: a valve bridge, and a pin. 53. The system of claim 48 wherein the hydraulic actuator piston provides substantially constant contact between the first and second rocker arms during all modes of engine operation. 54. The system of claim 53 wherein the hydraulic actuator piston is selectively locked during an exhaust gas recirculation mode of engine operation. 55. The system of claim 48 further comprising a means for biasing the second rocker arm toward the means for imparting one or more second valve actuation motions. 56. The system of claim 48 further comprising a means for biasing the second rocker arm toward the first rocker arm. 57. The system of claim 48 further comprising means for selectively locking the first rocker arm and the second rocker arm together. 58. The system of claim 48 further comprising means for adjusting a lash space between the actuator piston and the first or second rocker arm.