Valve bridge Anti-dislodgement structures

Abstract

A valve train assembly for an internal combustion engine. The valve train assembly includes a rocker arm assembly for actuating a valve. The rocker arm assembly includes a rocker arm body defining a valve end of the rocker arm assembly. A lost motion assembly is attached to the rocker arm assembly. The lost motion assembly includes a roller. A latch pin assembly is provided for selectively coupling the rocker arm body and the lost motion assembly together. The latch pin assembly has a latched position wherein the rocker arm body and the lost motion assembly are coupled and an unlatched position wherein the rocker arm body and the lost motion assembly are uncoupled. An anti-dislodgement element is configured to limit a rotation of the rocker arm body when the rocker arm body is at a predetermined angle.

Description

PRIORITY

[0001] This application claims the benefit of priority of provisional U.S. patent application Ser. Nos. 63 / 499,431, filed May 1, 2023; 63 / 499,472, filed May 1, 2023; and 63 / 501,713, filed May 12, 2023, the contents of which are incorporated herein by reference in their entirety.FIELD

[0002] The subject application relates to, in general, a rocker arm assembly for use in a combustion engine wherein the rocker arm assembly includes a lost motion mechanism for deactivating a roller. More particularly, this application relates to valve anti-dislodgement structures for reducing the likelihood that a valve bridge will be dislodged from one or more valve stems during operation.BACKGROUND

[0003] An internal combustion engine may utilize a lost motion mechanism for deactivating a rocker arm body. When a latch assembly of a rocker arm assembly is in a latched position, the rocker arm body and a lost motion mechanism are coupled together. When the latch assembly is in an unlatched position, the rocker arm body and the lost motion mechanism are decoupled from each other such that they may move relative to each other. During operation, excessive movement of the rocker arm body relative to the lost motion mechanism may cause a valve bridge of the rocker arm assembly to become dislodged from one or more valve stems associated with the valve bridge.

[0004] The present application discloses an anti-dislodgement structures for hindering a valve bridge from becoming dislodged from one or more valves.SUMMARY OF THE INVENTION

[0005] There is provided a valve train assembly for an internal combustion engine. The valve train assembly includes a rocker arm assembly for actuating a valve. The rocker arm assembly includes a rocker arm body defining a valve end of the rocker arm assembly. The rocker arm body is rotatable about a main rocker shaft. A lost motion assembly is attached to the rocker arm assembly. The lost motion assembly includes a roller. A latch pin assembly is provided for selectively coupling the rocker arm body and the lost motion assembly together. The latch pin assembly has a latched position wherein the rocker arm body and the lost motion assembly are coupled and an unlatched position wherein the rocker arm body and the lost motion assembly are uncoupled. A cam is disposed on a cam shaft. The cam is configured to engage the roller of the lost motion assembly. An anti-dislodgement element is configured to limit a rotation of the rocker arm body when the latch pin assembly is in the unlatched position and the rocker arm body is at predetermined angle.

[0006] In the foregoing valve train assembly, the anti-dislodgement element is an integral shoulder formed on the cam shaft and the shoulder is dimensioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

[0007] In the foregoing valve train assembly, the anti-dislodgement element is a protrusion extending from the rocker arm body and the protrusion is dimensioned to engage the cam shaft when the rocker arm body is at the predetermined angle.

[0008] In the foregoing valve train assembly, the protrusion is a separate component attachable to the rocker arm body.

[0009] In the foregoing valve train assembly, the anti-dislodgement element is a collar dimensioned to be mounted on the camshaft and the collar is dimensioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

[0010] In the foregoing valve train assembly, the collar includes a first portion and a second portion that are connectable together.

[0011] In the foregoing valve train assembly, the anti-dislodgement element is a shaft ring attachable to the main rocker shaft and the shaft ring includes a shoulder positioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

[0012] In the foregoing valve train assembly, a key is at least partially positioned within a slot in the cam shaft and at least partially within a slot in the shaft ring to at least rotationally secure the shaft ring to the cam shaft.

[0013] In the foregoing valve train assembly, the anti-dislodgement element is a bracket fixed relative to the rocker arm body and the bracket includes a contact surface positioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

[0014] In the foregoing valve train assembly, the bracket is mounted to a cylinder head of the internal combustion engine.

[0015] In the foregoing valve train assembly, the contact surface is positioned between the rocker arm body and the cam shaft.

[0016] In the foregoing valve train assembly, the bracket is configured to deflect and contact the cam shaft when the rocker arm body is at a second predetermined angle.

[0017] In the foregoing valve train assembly, the bracket includes a second contact surface to engage another portion of the rocker arm body when the rocker arm body is at the predetermined angle.BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1 is a side perspective view of rocker arm assembly attached to a main rocker shaft and a cam shaft of an engine;

[0019] FIG. 2 is a side perspective view of the rocker arm assembly of FIG. 1, adjacent a cam;

[0020] FIG. 3 is a sectioned view taken along line 3-3 of FIG. 2;

[0021] FIG. 4A is a side view of the rocker arm assembly of FIG. 1, showing the rocker arm assembly in a valve bridge engaged position;

[0022] FIG. 4B is a side view of the rocker arm assembly of FIG. 1, showing a valve bridge in a dislodged position;

[0023] FIG. 5 is a rear perspective view of a rocker arm assembly, according to a first embodiment;

[0024] FIG. 6 is a side view of the rocker arm assembly of FIG. 5;

[0025] FIG. 7 is a rear view of the rocker arm assembly of FIG. 5;

[0026] FIG. 8 is a rear perspective view of a rocker arm assembly, according to a second embodiment;

[0027] FIG. 9 is a side view of the rocker arm assembly of FIG. 8;

[0028] FIG. 10 is a bottom perspective view of the rocker arm assembly of FIG. 8, showing a cam shaft removed;

[0029] FIG. 11 is a rear perspective view of a rocker arm assembly, according to a third embodiment;

[0030] FIG. 12A is a perspective view of a collar of the rocker arm assembly of FIG. 11;

[0031] FIG. 12B is a section view taken along line 12-12 of FIG. 12A;

[0032] FIG. 13 is a perspective view of a rocker arm assembly, according to a fourth embodiment;

[0033] FIG. 14 is a perspective view of the rocker arm assembly of FIG. 13, showing an anti-dislodgement assembly exploded from the rocker arm assembly;

[0034] FIG. 15A is a right side perspective view of a lock ring of the anti-dislodgement assembly of FIG. 13;

[0035] FIG. 15B is a left side perspective view of the lock ring of FIG. 15A;

[0036] FIG. 15C is a top view of the lock ring of FIG. 15A;

[0037] FIG. 16 is a bottom view of the lock ring of FIG. 15A;

[0038] FIG. 17 is a rear perspective view of a rocker arm assembly, according to a fifth embodiment;

[0039] FIG. 18 is a sectioned view taken from line 18-18 of FIG. 17;

[0040] FIG. 19A is a front view of a compliance hard stop of the rocker arm assembly of FIG. 17;

[0041] FIG. 19B is a rear view of the compliance hard stop of FIG. 19A;

[0042] FIG. 20 is a rear perspective view of a rocker arm assembly, according to a sixth embodiment;

[0043] FIG. 21A is a front view of a compliance hard stop of the rocker arm assembly of FIG. 20; and

[0044] FIG. 21B is a rear view of the compliance hard stop of FIG. 21A.DETAILED DESCRIPTION

[0045] The following presents a description of the disclosure; however, aspects may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Furthermore, the following examples may be provided alone or in combination with one or any combination of the examples discussed herein. Directional references such as “left” and “right” are for ease of reference to the figures.

[0046] Referring to FIG. 1, a rocker arm assembly 10 is shown. The rocker arm assembly 10, in general, includes a body 30 and a lost motion assembly 50 and has a valve end 12 configured to engage a valve bridge 22 and a cam end 14 configured to engage a cam 18 (FIG. 2).

[0047] The body 30 includes a rocker bore 32 that is dimensioned to receive a main rocker shaft 16 for allowing the body 30 to pivot thereon via actuation by the cam 18 (FIG. 2). The cam 18 includes a cam profile that is configured to cause the body 30 to pivot about the rocker shaft 16 at predetermined intervals as the cam 18 rotates.

[0048] Referring to FIG. 2, the lost motion assembly 50 is pivotably attached to the body 30. The lost motion assembly 50 includes a bracket 52 having a roller 58 rotatably attached to a first end of the bracket 52. The roller 58 is dimensioned and positioned to engage the cam 18, as described in detail below. A pivot is formed at an opposite second end of the bracket 52 from the roller 58. In the embodiment illustrated, the pivot is defined by a pivot rod 56 that extends outwardly from opposite sides of the bracket 52. In the embodiment illustrated, the bracket 52 is made from sheet metal that is bent to define a first leg 54a and a second parallel leg 54b. In this embodiment, the roller 58 is rotatably held between the first leg 54a and the second leg 54b.

[0049] A first spring 60A is positioned on one end of the pivot rod 56 and a second spring 60B is positioned on an opposite end of the pivot rod 56. Each spring 60A, 60B includes a coiled body portion 62, a first leg 64 and a second leg 66. Each coiled body portion 62 is positioned around one end of the pivot rod 56. Each first leg 64 extends from the coiled body portion 62 and is positioned on a top of one end of a peg 59a, 59b. Each second leg 66 extends from the coiled body portion 62 and extends into a mating hole (not shown) in the body 30.

[0050] The springs 60A, 60B are pre-wound such that the first leg 64 applies a downward biasing force to the respective peg 59a, 59b and by association, the bracket 52. The downward force applied to the bracket 52 biases the bracket 52 downwardly in a clockwise direction (as viewed in FIG. 2) to a first position wherein the pegs 59a, 59b engage a top of the body 30. In this respect, the pegs 59a, 59b act as “stops” to limit the clockwise pivoting of the bracket 52.

[0051] Referring to FIG. 3, a latch pin assembly 70 is positioned in the body 30 and the roller 58. The latch pin assembly 70 includes an actuation piston 72, a latch pin 74, a latch piston 76, a spring 78 and first and second caps 82a, 82b. The latch pin 74 is dimensioned and positioned to be partially received in the roller 58 and a first end caps 39a of one leg of the body 30. The actuation piston 72 is positioned between the first cap 82a and the latch pin 74 and the latch piston 76 is positioned adjacent an opposite end of the latch pin 74. The spring 78 is compressed between the latch piston 76 and the second cap 82b to bias the latch piston 76, the latch pin 74 and the actuation piston 72 toward the first cap 82a. When the bracket 52 is in the first position, also referred to as a “latched position” of the lost motion assembly 50, the bracket 52 and the body 30, when actuated by the cam 18 pivot about the rocker shaft 16 as a unitary body.

[0052] When a lost motion is desired, i.e., when it is desired that motion from the cam 18 is not translated to the valve end 12, pressurized fluid is supplied to a space between the first cap 82a and the actuation piston 72 to force the actuation piston 72 to move toward a second end cap 39b of the other leg of the body 30. As the actuation piston 72 moves, the latch pin 74 and the latch piston 76 are forced toward the second end cap 39b thereby compressing the spring 78. Once the latch pin 74 is completely within the roller 58, the bracket 52 is unlatched from the body 30 such that movement from the cam 18 is applied only to the bracket 52 and the bracket 52 pivots about the pivot rod 56, i.e., away from the first position against the biasing force of the springs 60A, 60B. This is referred to as a “lost motion” movement.

[0053] Referring to FIGS. 4A and 4B, during operation, when the latch pin 74 is in the latched position, motion from the cam 18 is applied to the body 30, thereby causing the body 30 to pivot (in the counterclockwise direction when viewed in FIG. 4A) about the main rocker shaft 16. As the body 30 pivots (in the counterclockwise direction when viewed in FIG. 4A), the valve bridge 22 is displaced (downwardly when viewed in FIG. 4A). The movement of the valve bridge 22, in turn, displaces the valves 24 (downwardly when viewed in FIG. 4A). During lost motion, i.e., when the latch pin 74 is in the unlatched position, the body 30 does not pivot and no motion is transferred to the valves 24.

[0054] Referring to FIG. 4B, during a critical shift the latch pin 74 may not fully engage to the latched position such that the lost motion assembly 50 is free to move relative to the body 30. Due to the force provide by valve springs 26 associated with the valves 24, the body 30 may over-rotate (in the clockwise direction when viewed in FIG. 4B) relative to the lost motion assembly 50. As the body 30 continues to rotate, the valve bridge 22 becomes dislodged from the distal ends of the valves 24. Once the body 30 begins to rotate back towards the valve bridge 22 (in the counter-clockwise direction in FIG. 4B), the valve bridge 22 may no longer align with the distal ends of the valves 24. This misalignment may cause a temporary or permanent failure in the operation of the rocker arm assembly 10.

[0055] Referring to FIGS. 5-7, according to a first embodiment, the cam 18 is placed on a cam shaft 90 that is formed to include a raised cylindrical shoulder 92. As shown in FIGS. 5-7, the shoulder 92 is configured to be positioned adjacent the cam 18 and to align with the first end cap 39a of the rocker arm body 30.

[0056] The shoulder 92 is positioned and dimensioned so that during a critical shift (described in detail above), the first end cap 39a of the body 30 abuts against the shoulder 92 and the rocker arm body 30 is thereby prevented from rotating past a predetermined angle. It is contemplated that the predetermined angle is selected as an angle that maintains the valve bridge 22 in contact with the valves 24 during the critical shift. The shoulder 92 acts as a physical “stop” to hinder the body 30 from over-rotating, e.g., to the position illustrated in FIG. 4B.

[0057] Referring to FIGS. 8-10, according to a second embodiment, a rocker arm assembly 210 is shown. Rocker arm assembly 210 is similar in most aspects to the rocker arm assembly 10 described above and identical numbers are used for identical parts and the description of those identical parts are not repeated below for brevity.

[0058] The body 230 of the rocker arm assembly 210 includes a protrusion 231 that extends from a lower portion of the first end cap 39a. The protrusion 231 is positioned and dimensioned so that during a critical shift (described in detail above), the protrusion 231 abuts against a cam shaft 17 when the body 30 reaches a predetermined angle. The protrusion 231 acts as a “stop” to hinder the body 30 from over-rotating, e.g., to the position illustrated in FIG. 4B. As described above, it is contemplated that the predetermined angle is selected as an angle that maintains the valve bridge 22 in contact with the valves 24 during the critical shift.

[0059] Referring to FIGS. 11-12A, according to a third embodiment, the cam 18 is placed on a cam shaft 390 that includes a collar assembly 392. The collar assembly 392 includes a first portion 394 and a second portion 396 that are joined together by a plurality of fasteners (not shown). Each portion 394, 396 includes a plurality of bored holes 398 that are dimensioned and positioned to align with and be in registry with mating threaded holes 399 formed in the other half portion 394, 396. As shown in FIG. 11, the collar assembly 392 (similar to the shoulder 92 described in detail above) is configured to be positioned adjacent the cam 18 and to align with the first end cap 39a of the rocker arm body 30. In the embodiment illustrated, the portions 394, 396 each define equal halves of the collar assembly 392. It is contemplated that the portions 394, 396 may be other than equal halves so long as, when combined, they extend around the cam shaft 390 a significant extend to secure the collar assembly 392 to the cam shaft 390.

[0060] The collar assembly 392 is positioned and dimensioned so that during a critical shift (described in detail above), the first end cap 39a of the body 30 abuts against the collar assembly 392 when the body 30 reaches a predetermined angle. The collar assembly 392 acts as a “stop” to hinder the body 30 from over-rotating, e.g., to the position illustrated in FIG. 4B. As described above, it is contemplated that the predetermined angle is selected as an angle that maintains the valve bridge 22 in contact with the valves 24 during the critical shift.

[0061] Referring to FIGS. 13-16, according to a fourth embodiment, a rocker arm assembly 410 includes a body 430 and two lost motion assemblies 450A, 450B. Similar to rocker arm assembly 10, the rocker arm assembly 410 includes a valve end 412 that is configured to engage a valve bridge (not shown) and a cam end 414 that is configured to engage a cam (not shown). In the embodiment illustrated, the rocker arm assembly 410 includes two lost motion assemblies 450A, 450B to allow for two different lost motion movements. It is contemplated that the rocker arm assembly 410 may have a single lost motion assembly.

[0062] Referring to FIG. 14, one side of the body 430 is notched to define a body stop 431. The body stop 431 is configured to define a stop of the body 430 that engages a shaft hard stop 440, as described in detail below.

[0063] The shaft hard stop 440 is a ring-shaped element that is dimensioned to be fixed to the main rocker shaft 416 at a predetermined position. Referring to FIGS. 15A-16, the hard stop 440 includes ring-shaped body 440a having a first projection 442 extending axially from one side of the body 440a and a second projection 444 extending from an opposite side thereof.

[0064] One side of the first projection 442 defines a stop surface 442a of the hard stop 440. The second projection 444 includes a recess 446 formed on an inner cylindrical surface thereof that is dimensioned and positioned to engage a key 419, as described in detail below.

[0065] Referring to FIG. 14, the main rocker shaft 416 includes a slot 416a that is dimensioned to receive a lower portion of the key 419. The key 419 is dimensioned to be received into the slot 416a such that an upper portion of the key 419 extends proud of an outer cylindrical surface of the main rocker shaft 416. After the key 419 is positioned in the slot 416a, the hard stop 440 is slid over the main rocker shaft 416 such that the recess 446 of the hard stop 440 receives the portion of the key 419 that is proud of the outer cylindrical surface of the main rocker shaft 416.

[0066] The slot 416a is positioned so that when the hard stop 440 is placed over the key 419, the stop surface 442a of the first projection 442 may abut against the body stop 431 of the body 430 when the body 30 rotates to a predetermined position. In particular, the slot 416a and the hard stop 440 are dimensioned and positioned to prevent the body 430 from over-rotating during a critical shift, as described in detail above.

[0067] Referring to FIGS. 17-19, according to a fifth embodiment, a hard stop 540 is placed adjacent the rocker arm assembly 10. The hard stop 540, in general, is an S-shaped element having a body portion 542, a first leg 544 and a second leg 546.

[0068] The first leg 544 is extends from one end of the body portion 542 and includes a recess or contact surface 544a. The second leg 546 extends from an opposite end of the body portion 542 and includes a mounting hole 548 extending therethrough. In the embodiment illustrated that first leg 544 and the second leg 546 extend perpendicularly from the body portion 542 and are skewed relative to each other.

[0069] The hard stop 540 is configured to be secured to the engine (e.g., to a cylinder head (not shown)) and is shaped such that the first leg 544 is spaced from the first end cap 39a of the body 30. As illustrated in FIG. 18, the first end cap 39a is spaced from a bottom of the recess 544a by a predetermined distance “d” when the roller 58 is on a base circle of the cam 18.

[0070] The hard stop 540 is dimensioned and positioned so that first end cap 39a may abut against the hard stop 540, in particular, the recess 544a, when the body 30 rotates to a predetermined position. In particular, the hard stop 540 is dimensioned and positioned to prevent the body 30 from over-rotating during a critical shift, as described in detail above. It is contemplated that the hard stop 540 is configured to deflect under the force of the body 30.

[0071] The hard stop 540 is configured such that as the body 30 continues to rotate the hard stop 540 deflects toward the cam shaft 17 and contacts the cam shaft 17. The cam shaft 17, thereby acts as a secondary stop in situations where the deflection of the hard stop 540 (caused by the body 30) continues beyond the predetermined distance. It is contemplated that a maximum deflection of the hard stop 540, as determined by the distance at which the hard stop 540 contacts the cam shaft 17, is selected so that repeated deflecting of the hard stop 540 will not result in the hard stop 540 failing (e.g., via fatigue) during the useful lift of the engine.

[0072] Referring to FIGS. 20-21B, according to a sixth embodiment, a hard stop 640 is placed adjacent the rocker arm assembly 410. The hard stop 640, in general, is a U-shaped element having a body portion 642 and two L-shaped legs 644, 646.

[0073] The first leg 644 includes a first portion 644a connected to an end of the body portion 642 and a second portion 644b that extends from a distal end of the first portion 644a. A mounting hole 648a is formed in the second portion 644b. In the embodiment illustrated, the second portion 644b extends perpendicularly from the first portion 644a.

[0074] The second leg 646 includes a first portion 646a connected to an opposite end of the body portion 642 and a second portion 646b that extends from a distal end of the first portion 646a. A mounting hole 648b is formed in the second portion 646b. In the embodiment illustrated, the second portion 646b extends perpendicularly from the first portion 646a.

[0075] A first recess or contact surface 642a and a second recess or contact surface 642b are formed in the body portion 642 near ends of the body portion 642. In the embodiment illustrated, the body portion 642 is U-shaped and defines an opening 643.

[0076] The hard stop 640 is configured to be secured to the engine (e.g., to a cylinder head (not shown)) and is shaped such that a bottom of the recess 642a, 642b are spaced from respective end caps 439a, 439b of the rocker arm assembly 410. The recesses 642a, 642b and the end caps 439a, 439b are dimensioned and configured to have a predetermined distance “d”′ therebetween when the roller 58 is on a base circle of the cam 18.

[0077] The hard stop 640 is dimensioned and positioned so that end caps 439a, 439b may abut against the hard stop 640, in particular, the recesses 642a, 642b when the body 430 rotates to a predetermined position. In particular, the hard stop 640 is dimensioned and positioned to prevent the body 430 from over-rotating during a critical shift, as described in detail above.

[0078] The foregoing anti-dislodgement structures are configured to be positioned on or near a rocker arm body to prevent the rocker arm body from rotating beyond a predetermined angle. This angle is selected as the angle that prevents a valve bridge from becoming dislodged from valves, during a critical shift of the rocker arm assembly.

[0079] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the claimed invention.

Claims

1. A valve train assembly for an internal combustion engine, the valve train assembly comprising:a rocker arm assembly for actuating a valve, the rocker arm assembly comprising a rocker arm body defining a valve end of the rocker arm assembly, the rocker arm body rotatable about a main rocker shaft;a lost motion assembly attached to the rocker arm assembly, the lost motion assembly comprising a roller;a latch pin assembly for selectively coupling the rocker arm body and the lost motion assembly together, the latch pin assembly having a latched position wherein the rocker arm body and the lost motion assembly are coupled and an unlatched position wherein the rocker arm body and the lost motion assembly are uncoupled;a cam disposed on a cam shaft, the cam configured to engage the roller of the lost motion assembly; andan anti-dislodgement element configured to limit a rotation of the rocker arm body when the latch pin assembly is in the unlatched position and the rocker arm body is at predetermined angle.

2. The valve train assembly of claim 1, wherein the anti-dislodgement element is an integral shoulder formed on the cam shaft, the integral shoulder dimensioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

3. The valve train assembly of claim 1, wherein the anti-dislodgement element is a protrusion extending from the rocker arm body, the protrusion dimensioned to engage the cam shaft when the rocker arm body is at the predetermined angle.

4. The valve train assembly of claim 3, wherein the protrusion is a separate component attachable to the rocker arm body.

5. The valve train assembly of claim 1, wherein the anti-dislodgement element is a collar dimensioned to be mounted on the cam shaft, the collar dimensioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

6. The valve train assembly of claim 5, wherein the collar includes a first portion and a second portion that are connectable together.

7. The valve train assembly of claim 1, wherein the anti-dislodgement element is a shaft ring attachable to the main rocker shaft, the shaft ring comprising a shoulder positioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

8. The valve train assembly of claim 7, wherein a key is positioned at least partially within a slot in the cam shaft and at least partially within a slot formed in the shaft ring to at least rotationally secure the shaft ring to the cam shaft.

9. The valve train assembly of claim 1, wherein the anti-dislodgement element is a bracket fixed relative to the rocker arm body, the bracket including a contact surface positioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

10. The valve train assembly of claim 9, wherein the bracket is mounted to a cylinder head of the internal combustion engine.

11. The valve train assembly of claim 9, wherein the contact surface is positioned between the rocker arm body and the cam shaft.

12. The valve train assembly of claim 11, wherein the bracket is configured to deflect and contact the cam shaft when the rocker arm body is at a second predetermined angle.

13. The valve train assembly of claim 9, wherein the bracket includes a second contact surface to engage another portion of the rocker arm body when the rocker arm body is at the predetermined angle.

14. A valve train assembly for an internal combustion engine, the valve train assembly comprising:a rocker arm assembly for actuating a valve, the rocker arm assembly comprising a rocker arm body defining a valve end of the rocker arm assembly, the rocker arm body rotatable about a main rocker shaft, wherein a pivot is formed at an end of the rocker arm body opposite from the valve end, the pivot defined by a pivot rod that extends outwardly from opposite sides of a bracket;a first spring comprising a coiled body portion positioned on one end of the pivot rod, the first spring configured to apply a biasing force to the rocker arm assembly;a lost motion assembly attached to the rocker arm assembly, the lost motion assembly comprising a roller configured to engage a cam disposed on a cam shaft;a latch pin assembly for selectively coupling the rocker arm body and the lost motion assembly together, the latch pin assembly having a latched position wherein the rocker arm body and the lost motion assembly are coupled and an unlatched position wherein the rocker arm body and the lost motion assembly are uncoupled; andan anti-dislodgement element configured to limit a rotation of the rocker arm body when the latch pin assembly is in the unlatched position and the rocker arm body is at predetermined angle.

15. The valve train assembly of claim 14, wherein the bracket of the rocker arm assembly comprises a first leg and a second leg parallel to the first leg, wherein the roller is disposed between the first and second legs of the bracket.

16. The valve train assembly of claim 15, wherein a peg extends through the first and second legs of the bracket, the peg configured to engage a top of the rocker arm body.

17. The valve train assembly of claim 16, wherein a first leg of the first spring is positioned on top of the peg to apply the biasing force onto the peg and the bracket such that the peg acts as a stop to limit pivoting of the bracket.

18. The valve train assembly of claim 15, wherein, when the latch pin assembly is in the unlatched position, the bracket pivots about the pivot rod away from the biasing force of the first spring.

19. The valve train assembly of claim 14, wherein the anti-dislodgement element is disposed on the cam shaft and dimensioned to engage the rocker arm body when the rocker arm body is at the predetermined angle.

20. The valve train assembly of claim 19, wherein the anti-dislodgement element provides a physical stop to prevent over-rotation of the rocker arm body.

Images