Method for cylinder constant refilling

Abstract

A valve train assembly for actuating an intake valve. The latch assembly is configured to selectively couple the retarded intake valve roller to the main rocker arm body. The lost motion assembly is configured to bias the retarded intake valve roller to a first position wherein the latch assembly is movable between a latched position and an unlatched position. The lost motion assembly is configured to allow the retarded intake valve roller to move a predetermined maximum distance when the latch assembly is in the unlatched position. When the latch assembly is in the unlatched position and after the retarded intake valve roller has moved a predetermined maximum distance, a portion of a retarded intake valve lift curve of the cam exerts additional movement on the retarded intake valve roller such that the retarded intake valve roller and the main rocker body are coupled together and move as a whole.

Description

[0001] priority

[0002] This application claims the benefit of priority to Provisional U.S. Patent Application Serial No. 63 / 511,410, filed June 30, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application generally relates to a rocker arm assembly for use in a combustion engine, wherein the rocker arm assembly includes two latching assemblies for activating or deactivating two rollers of the rocker arm assembly. More specifically, this application relates to a rocker arm assembly having a first latching assembly and a second latching assembly configured to selectively engage the first and second rollers to a main rocker arm body. Background Technology

[0004] Cylinder deactivation (CDA) is an engine management control method in multi-cylinder engines that selects the cylinders by cutting off fuel supply and valve movement. CDA is applied to internal combustion engines to help improve performance. For example, CDA reduces fuel consumption and increases exhaust temperature, and is also known as aftertreatment thermal management. During CDA, gases are trapped inside the engine cylinders. Over time, the gas pressure dissipates due to leakage in the cylinders, and therefore the gas temperature drops. Eventually, a negative pressure is created inside the cylinders, which can lead to unwanted oil leakage into the combustion engine. The presence of oil in the cylinders and the low temperature can be detrimental to engine operation in terms of emissions, and in extreme cases, can cause vapor crystal formation inside the cylinders. The aforementioned problems are particularly pronounced when the intake valves are deactivated before the exhaust valves. It is desirable to recharge the gases in the cylinders during CDA by means of a small valve opening.

[0005] This application provides a system for achieving small valve opening in an internal combustion engine having a delayed intake valve closing (LIVC) system combined with CDA. Summary of the Invention

[0006] A valve mechanism assembly for actuating an intake valve is provided. The valve mechanism assembly includes a rocker arm assembly having a main rocker arm body with a valve end. A first latching assembly is configured to selectively engage a main intake valve roller to the main rocker arm body, the first latching assembly having a latched position, in which the main intake valve roller is engaged to the main rocker arm body, and in the unlatched position, the main intake valve roller is disengaged from the main rocker arm body. A first actuation assembly is configured to bias the main intake valve roller to a first position, wherein the first latching assembly is movable between the latched position and the unlatched position. A second latching assembly is configured to selectively engage a delayed intake valve roller to the main rocker arm body. The second latching assembly has a latched position, in which the delayed intake valve roller is engaged to the main rocker arm body, and in the unlatched position, the delayed intake valve roller is disengaged from the main rocker arm body. The second actuation assembly is configured to bias the delayed intake valve roller to a first position, wherein the second latching assembly is movable between a latched position and an unlocked position. The second actuation assembly is configured to allow the delayed intake valve roller to move a predetermined maximum distance relative to the main rocker arm body when the second latching assembly is in the unlocked position. A first cam is configured to engage the main intake valve roller, wherein the first cam has a main intake valve lift profile. The second cam is configured to engage the delayed intake valve roller, wherein when the first latching assembly and the second latching assembly are in the unlocked position and after the delayed intake valve roller has moved the predetermined maximum distance, a portion of the delayed intake valve lift profile of the second cam applies additional movement to the delayed intake valve roller, such that the delayed intake valve roller and the main rocker arm body are coupled together and move as a whole.

[0007] In the aforementioned valve mechanism assembly, the maximum lift of the delayed intake valve lift curve exceeds the maximum lift of the main intake valve lift curve by a predetermined height.

[0008] In the aforementioned valve mechanism assembly, the first aerodynamic spring of the first aerodynamic assembly is fixed at one end to the main rocker arm body and at the second end to a bracket that holds the main intake valve roller, and the second aerodynamic spring of the second aerodynamic assembly is fixed at one end to the main rocker arm body and at the second end to a bracket that holds the delayed intake valve roller.

[0009] In the aforementioned valve mechanism assembly, when the first latch assembly and the second latch assembly are not latched, the lift of the second cam compresses the second air spring.

[0010] In the aforementioned valve mechanism assembly, during the cylinder deactivation mode, the first latch assembly and the second latch assembly are in the unlatched position.

[0011] In the aforementioned valve mechanism assembly, when the first latch assembly is in the latched position, the main intake valve roller and the main rocker arm body pivot as a whole.

[0012] In the aforementioned valve mechanism assembly, when the second latch assembly is in the latched position, the delayed intake valve roller and the main rocker arm body pivot as a whole.

[0013] In the aforementioned valve mechanism assembly, during the delayed intake valve closing mode, the first latch assembly and the second latch assembly are in the latched position.

[0014] In the aforementioned valve mechanism assembly, when both the first latch assembly and the second latch assembly are in the latched position, the displacement applied to the valve end of the main rocker arm body is the larger of the main intake valve lift curve and the delayed intake valve lift curve.

[0015] A valve mechanism assembly for actuating an intake valve is also provided. The valve mechanism assembly includes a rocker arm assembly having a main rocker arm body. A latching assembly is configured to selectively engage a delayed intake valve roller to the main rocker arm body. The latching assembly has a latched position and an unlatched position, in which the delayed intake valve roller is engaged to the main rocker arm body, and in the unlatched position, the delayed intake valve roller is disengaged from the main rocker arm body. An actuation assembly is configured to bias the delayed intake valve roller to a first position, wherein the latching assembly is movable between the latched position and the unlatched position. The actuation assembly is configured to allow the delayed intake valve roller to move a predetermined maximum distance when the latching assembly is in the unlatched position. A cam is configured to engage the delayed intake valve roller. When the latch assembly is in the unlocked position and after the delayed intake valve roller has moved a predetermined maximum distance, a portion of the cam's delayed intake valve lift curve applies additional movement to the delayed intake valve roller, causing the delayed intake valve roller and the main rocker arm body to engage together and move as a whole.

[0016] In the aforementioned valve mechanism assembly, the rocker arm assembly further includes a second latching assembly configured to selectively engage the main intake valve roller to the main rocker arm body. The second latching assembly has a latched position and an unlocked position, in which the main intake valve roller is engaged to the main rocker arm body, and in the unlocked position, the main intake valve roller is disengaged from the main rocker arm body. A second aerodynamic assembly is configured to bias the main intake valve roller to a first position, wherein the second latching assembly is movable between the latched and unlocked positions. A second cam is configured to engage the main intake valve roller, wherein the second cam has a main intake valve lift profile. Attached Figure Description

[0017] Figure 1A This is a side perspective view of the rocker arm assembly used in the engine; Figure 1B yes Figure 1A A cross-sectional view of the latch pin assembly of the rocker arm assembly; Figure 2 It shows including Figure 1A The lift curves of the main intake valve lift and LIVC lift of the valve mechanism assembly of the rocker arm assembly; Figure 3 An embodiment of the present invention is shown. Figure 1A The lift curves of the main intake valve and the modified LIVC lift of the valve mechanism assembly; Figure 4 The lift curves of the main intake valve lift and the modified LIVC lift are shown, where the main intake valve lift is activated and the modified LIVC lift is in idling. Figure 5 The lift curves for the main intake valve lift and the modified LIVC lift are shown, where both the main intake valve lift and the modified LIVC lift are activated. Figure 6 The lift curves of the main intake valve lift and the modified LIVC lift are shown, where both the main intake valve lift and the modified LIVC lift are in the idling phase. Figure 7 The lift curves for the main intake valve lift and the modified LIVC lift are shown, where the main intake valve lift is in idling and the modified LIVC lift is activated. Detailed Implementation

[0018] The following is a description of this disclosure; however, various aspects may be embodied in many different forms and should not be construed as limited to the embodiments described 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 convenience of reference to the accompanying drawings.

[0019] refer to Figure 1A The diagram shows a rocker arm assembly 10 and cams 22 and 32 of a valve mechanism assembly 1. The rocker arm assembly 10 includes a main rocker arm body 11. The main rocker arm body 11 includes a rocker arm shaft bore 12, a valve end 13, and a cam end 14. The rocker arm shaft bore 12 is sized and configured to receive a rocker arm shaft (not shown) to allow the main rocker arm body 11 to pivot thereon. The valve end 13 is configured to engage a valve stem or valve bridge (not shown). The cam end 14 of the main rocker arm body 11 is configured to selectively engage a first cam 22 and a second cam 32 of the valve mechanism assembly 1 based on the state of their respective pneumatic components 20 and 30.

[0020] A first pneumatic assembly 20 and a second pneumatic assembly 30 are configured to bias their respective rollers 21, 31 to a first position. The first pneumatic assembly 20 includes a first pneumatic spring 16 and a first bracket 18. One end of the first pneumatic spring 16 is fixed to the main rocker arm body 11 at a first support 16a, and the opposite end of the first pneumatic spring 16 is fixed to the first bracket 18. The main intake valve roller 21 is rotatably attached to the first bracket 18. The first pneumatic spring 16 is configured to bias the first bracket 18 and the corresponding main intake valve roller 21 to the first position, wherein a first latching assembly 40 is movable between a latched position and an unlocked position, as described in detail below.

[0021] The second pneumatic assembly 30 includes a second pneumatic spring 17 and a second bracket 19. One end of the second pneumatic spring 17 is fixed to the main rocker arm body 11 at a second support 17a, and the opposite end of the second pneumatic spring 17 is fixed to the second bracket 19. A delayed intake valve roller 31 is rotatably attached to the second bracket 19. The second pneumatic spring 17 is configured to bias the second bracket 19 and the corresponding delayed intake valve roller 31 to a first position, wherein the second latching assembly 50 is movable between a latched position and an unlatched position, as described in detail below. The second pneumatic assembly 30 has a maximum pneumatic travel LM. MAX When the second latch assembly 50 is in the unlocked position as described in detail below, the second bracket (and the delayed intake valve roller 31 attached thereto) can move the maximum idling stroke relative to the main rocker arm body 11.

[0022] The rocker arm assembly 10 is configured to actuate an intake valve (not shown). A main intake valve roller 21 is sized and positioned to engage a first cam 22, while a delayed intake valve roller 31 is sized and positioned to engage a second cam 32. The first cam 22 and the second cam 32 can be, for example, rotatable bodies provided with at least one protrusion. The cam profile is configured to convert the rotational motion of the first cam 22 and the second cam 32 into rotational motion of the main rocker arm body 11 and lateral motion of the valve (not shown). The cam profile includes vertices 22a and 32a, which, when viewed in profile, have heights 22b and 32b, defined as the distance from the base circle of the first cam 22 and the second cam 32 to the vertices 22a and 32a.

[0023] The rotation of the first cam 22 and the second cam 32 is synchronized with the movement of the corresponding piston (not shown), specifically, with the movement of the piston moving between the top dead center and bottom dead center positions in the piston chamber (not shown). The first cam 22 has a main intake valve lift curve, and the second cam 32 has a LIVC lift curve. The aforementioned curves will be discussed in more detail below.

[0024] The first latching assembly 40 for the main intake valve roller 21 can be used to selectively engage and disengage the main intake valve roller 21 and the main rocker arm body 11. (Reference) Figure 1A The first latch assembly 40 is shown below and described below. The description of the first latch assembly 40 also applies to the second latch assembly 50, and for the sake of brevity, it will not be repeated below.

[0025] The first latch assembly 40 includes a latch pin 40a, an actuating piston 40b, a latch piston 40c, a spring 40d, and a first cover 40e and a second cover 40f. The latch pin 40a is dimensioned and positioned to be partially received within the main rocker arm body 11. The actuating piston 40b is positioned between the first cover 40e and the latch pin 40a, and the latch piston 40c is positioned adjacent to the opposite end of the latch pin 40a. The spring 40d is compressed between the latch piston 40c and the second cover 40f to bias the latch piston 40c, the latch pin 40a, and the actuating piston 40b toward the first cover 40e.

[0026] When the first latch assembly 40 is in the latched position, the latch pin 40a is partially disposed in both the main rocker arm body 11 and the first bracket 18, such that the main intake valve roller 21 and the main rocker arm body 11 are connected to each other. In this latched state, the first bracket 18, the main intake valve roller 21, and the main rocker arm body 11 pivot as a whole. Further, in this latched position, the lift curve of the first cam 22 is applied to the main intake valve roller 21, such that the first bracket 18, the main intake valve roller 21, and the main rocker arm body 11 pivot together about the main rocker arm axis (not shown).

[0027] To prevent the first latch assembly 40 from latching, pressurized fluid is supplied to the space between the first cover 40e and the actuating piston 40b, forcing the actuating piston 40b toward the second cover 40f. As the actuating piston 40b moves, the latch pin 40a and the latch piston 40c are forced toward the second cover 40f, thereby compressing the spring 40d. Once the latch pin 40a is fully within the first bracket 18, the first bracket 18, the main intake valve roller 21, and the main rocker arm body 11 are disengaged, causing the movement of the main intake valve roller 21 to compress the first idler spring 16. Therefore, the movement of the first cam 22 is not applied to the main rocker arm body 11. This is referred to as "idle movement".

[0028] The second latching assembly 50 for the delayed intake valve roller 31 can be used to selectively connect and disconnect the second bracket 19, the delayed intake valve roller 31, and the main rocker arm body 11. The second latching assembly 50 includes the same components as those described in detail above with respect to the first latching assembly 40, and these components operate in the same manner as those described above with respect to the first latching assembly 40, except that they are applied to the delayed intake valve roller 31.

[0029] When the second latch assembly 50 is in the latched position, the second bracket 19, the delayed intake valve roller 31, and the main rocker arm body 11 are connected to each other such that they pivot as a whole when the cam 32 moves the delayed intake valve roller 31. In this latched position, the lift profile of the second cam 32 is applied to the delayed intake valve roller 31, causing the second bracket 19, the delayed intake valve roller 31, and the main rocker arm body 11 to pivot together about the main rocker arm axis.

[0030] When the second latch assembly 50 is not latched, the second bracket 19, the delayed intake valve roller 31, and the main rocker arm body 11 are disconnected, causing the movement of the delayed intake valve roller 31 to compress the second idler spring 17. Therefore, the movement of the second cam 32 is not applied to the main rocker arm body 11. This is referred to as "idle movement".

[0031] When both the first latch assembly 40 and the second latch assembly 50 are latched, both the main intake valve roller 21 and the delayed intake valve roller 31 are engaged with the main rocker arm body 11 and pivot as a whole. The displacement of the valve (not shown) applied at the valve end 13 will be the greater of the lift of the first cam 22 and the lift of the second cam 32 at any cam angle.

[0032] Figures 2 to 7 A graphical representation is provided for comparing the relative heights of the lift curves. In the illustrated embodiment, the ratio of the cam lift curve to the actual lift experienced at the valve end 13 of the main rocker arm body 11 is 1:1. It is conceivable that in practical applications, this ratio may not be 1:1. Figure 2 As shown, traditionally, the maximum lift 2L of the delayed intake valve roller 31 is equal to the maximum lift 2M of the main intake valve roller 21.

[0033] This application provides a modified lift profile 3b on the second cam 32 to allow for constant recharge valve lift when the rocker arm assembly 10 is in CDA mode. Reference Figure 3 A portion 3c of the modified lift curve 3b of the second cam 32 exceeds the maximum aerodynamic stroke LM of the second aerodynamic assembly 30. MAX In other words, when the second latch assembly 50 is not latched, the lift of the second cam 32, which has a modified lift curve 3b, causes the second bracket 19 (and the delayed intake valve roller 31 attached thereto) to compress the second air spring 17. The second bracket 19 is designed such that the maximum distance it can move relative to the main rocker arm body 11 is the maximum air stroke LM. MAX Once the second support 19 has moved its maximum idle stroke LM MAXAt the distance, the second bracket 19 engages with the main rocker arm body 11, that is, it is reconnected to the main rocker arm body 11, such that any additional lift provided by the second cam 32 is applied to the main rocker arm body 11, the delayed intake valve roller 31, and the second bracket 19 as a whole. Maximum ergonomic stroke LM MAX It was selected as the maximum height greater than the main intake lift curve 2a.

[0034] refer to Figure 4 The diagram illustrates the main intake lift curve 2a and the modified lift curve 3b during normal operation when the first latching assembly 40 is latched and the second latching assembly 50 is not latched. When the first latching assembly 40 is latched and the second latching assembly 50 is not latched, the main intake lift curve 2a is applied to the main intake valve roller 21. Although the second latching assembly 50 is not latched, a portion 3c of the modified lift curve 3b is applied to the delayed intake valve roller 31. The portion 3c of the modified lift curve 3b applied to the delayed intake valve roller 31 exceeds the maximum aerodynamic stroke LM. MAX The part.

[0035] Specifically, as the first cam 22 and the second cam 32 rotate, the main rocker arm body 11 rotates according to the main intake lift curve 2a of the first cam 22. The second cam 32 approaches the maximum idle stroke LM in the modified lift curve 3b. MAX When part 3c is in operation, this part 3c compresses the second idler spring 17, so that no movement is transmitted to the main rocker arm body 11. For example... Figure 4 As shown, the entire portion 3c is smaller than the main intake lift curve 2a and occurs during the main intake lift curve 2a, so that no motion from portion 3c is applied to the main rocker arm body 11.

[0036] refer to Figure 5 When the first latching assembly 40 and the second latching assembly 50 are latched, both the main intake lift curve 2a and the modified lift curve 3b are applied to the main rocker arm body 11. This operating mode is called Modified Delayed Intake Valve Closing (LIVC) because the closing of the intake valve is delayed according to the modified lift curve 3b. This is because the modified lift curve 3b matches or exceeds the main intake lift curve 2a in all cases.

[0037] The system in standard mode ( Figure 4 ) and LIVC mode ( Figure 5 The behavior under these conditions is similar to a "normal" LIVC system, except that the shape of the LIVC lift is slightly different. For example... Figure 5 As shown, both the first latch assembly 40 and the second latch assembly 50 are latched during LIVC mode.

[0038] Figure 6The main intake lift curve 2a and the modified lift curve 3b are shown in cylinder deactivation (CDA) mode. In CDA mode, neither the first latch assembly 40 nor the second latch assembly 50 is latched. In this state, the main intake valve roller 21 and the delayed intake valve roller 31 are disconnected from the main rocker arm body 11. The modified lift curve 3b of the second cam 32 exceeds the maximum idle stroke LM as the first cam 22 and the second cam 32 rotate. MAX The portion (as discussed above) now causes the main rocker arm body 11 to follow the recharge lift 6 (the recharge lift 6 is the same as the portion 3c discussed in detail above). In other words, when the second cam 32 reaches the maximum idle stroke LM in its stroke... MAX When part 3c is used, the maximum aerodynamic stroke LM of the second aerodynamic component 30 is exceeded. MAX Once exceeded, recharge lift 6 is applied to the main rocker arm body 11, thereby opening the valve (not shown). This small lift, namely recharge lift 6, enables constant recharge functionality, wherein the valve (not shown) associated with the rocker arm assembly 10 is periodically opened during CDA mode.

[0039] Figure 7 An alternative LIVC mode is shown, in which the first latch assembly 40 is not latched and the second latch assembly 50 is latched, such that the main intake lift curve 2a is not activated and the modified lift curve 3b is activated. In other words, the delayed intake valve roller 31 is engaged with the main rocker arm body 11, while the main intake valve roller 21 is disengaged, such that the movement experienced by the main rocker arm body 11 is the modified lift curve 3b. This alternative LIVC mode is similar to the reference mode. Figure 5 The LIVC mode is discussed, but only the second latch assembly 50 is required to be in the latched position.

[0040] The rocker arm assembly according to this disclosure thus briefly opens the intake valve during CDA mode to allow air to enter the piston chamber.

[0041] While various features have been presented above, it should be understood that these features can be used individually and / or in any combination thereof. Furthermore, it should be understood that variations and modifications will occur to those skilled in the art to which the claimed examples pertain. Although these illustrations provide exemplary embodiments, they are not necessarily drawn to scale and may include additional or alternative elements in suitable operation.

Claims

1. A valve mechanism assembly for actuating an intake valve, the valve mechanism assembly comprising: The rocker arm assembly includes: The main rocker arm body has a valve end; A first latching assembly is configured to selectively engage a main intake valve roller to the main rocker arm body. The first latching assembly has a latched position and an unlocked position, in which the main intake valve roller is engaged to the main rocker arm body, and in the unlocked position, the main intake valve roller is disengaged from the main rocker arm body. A first aerodynamic assembly is configured to bias the main intake valve roller to a first position, wherein the first latching assembly is movable between the latched position and the unlatched position; A second latching assembly is configured to selectively engage a delayed intake valve roller to the main rocker arm body. The second latching assembly has a latched position and an unlocked position, in which the delayed intake valve roller is engaged to the main rocker arm body, and in the unlocked position, the delayed intake valve roller is disengaged from the main rocker arm body. A second aerodynamic assembly is configured to bias the delayed intake valve roller to a first position, wherein the second latching assembly is movable between the latched position and the unlatched position, and the second aerodynamic assembly is configured to allow the delayed intake valve roller to move a predetermined maximum distance relative to the main rocker arm body when the second latching assembly is in the unlatched position; A first cam is configured to engage the main intake valve roller, wherein the first cam has a main intake valve lift profile; and The second cam is configured to engage the delayed intake valve roller, wherein, when the first latch assembly and the second latch assembly are in the unlatched position and after the delayed intake valve roller has moved the predetermined maximum distance, a portion of the delayed intake valve lift curve of the second cam applies additional movement to the delayed intake valve roller, such that the delayed intake valve roller and the main rocker arm body are coupled together and move as a whole.

2. The valve mechanism assembly according to claim 1, wherein, The maximum lift of the delayed intake valve lift curve exceeds the maximum lift of the main intake valve lift curve by a predetermined height.

3. The valve mechanism assembly according to claim 1, wherein, The first aerodynamic spring of the first aerodynamic assembly is fixed at one end to the main rocker arm body and at the second end to a bracket that holds the main intake valve roller, and the second aerodynamic spring of the second aerodynamic assembly is fixed at one end to the main rocker arm body and at the second end to a bracket that holds the delayed intake valve roller.

4. The valve mechanism assembly according to claim 3, wherein, When the first latch assembly and the second latch assembly are not latched, the lift of the second cam compresses the second idler spring.

5. The valve mechanism assembly according to claim 1, wherein, During the cylinder deactivation mode, the first latch assembly and the second latch assembly are in the unlatched position.

6. The valve mechanism assembly according to claim 1, wherein, When the first latch assembly is in the latch position, the main intake valve roller and the main rocker arm body pivot as a whole.

7. The valve mechanism assembly according to claim 1, wherein, When the second latch assembly is in the latch position, the delayed intake valve roller and the main rocker arm body pivot as a whole.

8. The valve mechanism assembly according to claim 1, wherein, During the delayed intake valve closing mode, the first latch assembly and the second latch assembly are in the latched position.

9. The valve mechanism assembly according to claim 1, wherein, When both the first latch assembly and the second latch assembly are in the latched position, the displacement applied to the valve end of the main rocker arm body is the larger of the main intake valve lift curve and the delayed intake valve lift curve.

10. A valve mechanism assembly for actuating an intake valve, the valve mechanism assembly comprising: The rocker arm assembly includes: Main rocker arm body; A latching assembly configured to selectively engage a delayed intake valve roller to the main rocker arm body, the latching assembly having a latched position and an unlatched position, wherein in the latched position the delayed intake valve roller is engaged to the main rocker arm body, and in the unlatched position the delayed intake valve roller is disengaged from the main rocker arm body; and An aerodynamic assembly is configured to bias the delayed intake valve roller to a first position, wherein the latching assembly is movable between the latched position and the unlatched position, and the aerodynamic assembly is configured to allow the delayed intake valve roller to move a predetermined maximum distance when the latching assembly is in the unlatched position; The cam is configured to engage the delayed intake valve roller; Specifically, when the latch assembly is in the unlatched position and after the delayed intake valve roller has moved the predetermined maximum distance, a portion of the delayed intake valve lift curve of the cam applies additional movement to the delayed intake valve roller, causing the delayed intake valve roller and the main rocker arm body to engage together and move as a whole.

11. The valve mechanism assembly of claim 10, wherein the rocker arm assembly further comprises: A second latching assembly is configured to selectively engage the main intake valve roller to the main rocker arm body. The second latching assembly has a latched position and an unlatched position, in which the main intake valve roller is engaged to the main rocker arm body, and in the unlatched position, the main intake valve roller is disengaged from the main rocker arm body. A second aerodynamic assembly is configured to bias the main intake valve roller to a first position, wherein the second latching assembly is movable between the latched position and the unlocked position; and A second cam is configured to engage the main intake valve roller, wherein the second cam has a main intake valve lift profile.

Images