Valve actuation system including rocker arm assembly with one-way coupling therebetween

Abstract

A system for actuating at least two engine valves includes a first rocker arm assembly operatively connected to a first valve actuation motion source and connected to a first engine valve. The first rocker arm assembly includes a first lost motion component disposed in series with the first input rocker arm and the first output rocker arm. A second rocker arm assembly is operatively connected to a second valve actuation motion source and to a second engine valve. The second rocker arm assembly comprises at least one second rocker arm. The system also includes a one-way coupling mechanism disposed between the first output rocker arm and the at least one second rocker arm such that the second valve actuation motion is transmitted from the at least one second rocker arm to the first output rocker arm and the first valve actuation motion is not transmitted from the first output rocker arm to the at least one second rocker arm.

Description

Technical Field

[0001] The present disclosure generally relates to internal combustion engines and, more particularly, to valve actuation systems including rocker arm assemblies having one-way couplings therebetween. Background Art

[0002] Engine operation requires valve actuation in an internal combustion engine. Generally, the valve actuation force for opening engine valves (i.e., intake, exhaust, or auxiliary engine valves) is transmitted by a valve train, where such valve actuation force may be provided by a primary motion source and / or an auxiliary motion source. As used herein, the descriptor "primary" refers to the so-called primary event engine valve motion, i.e., the valve motion used during positive power generation, during which fuel is burned in an engine cylinder to provide a net engine power output; and the descriptor "auxiliary" refers to other engine valve motions for purposes other than positive power generation (e.g., compression release braking, exhaust braking, cylinder deactivation, cylinder cut-off, brake gas recirculation (BGR), etc.) or motions other than positive power generation (e.g., internal exhaust gas recirculation (IEGR), variable valve actuation (VVA), early exhaust valve opening (EEVO), late intake valve closing (LIVC), swirl control, etc.).

[0003] In many internal combustion engines, the primary motion source and / or the auxiliary motion source may be provided by a fixed profile cam and, more particularly, by one or more fixed lobes or bumps, which may be an integral part of each cam. If the intake valve and / or exhaust valve timing and lift can be changed, beneficial effects such as performance improvement, fuel economy improvement, emission reduction, and better vehicle drivability can be achieved. However, using a fixed profile cam may make it difficult to adjust the timing and / or amount of engine valve lift to optimize them for various engine operating conditions.

[0004] Given a fixed cam profile, one way to adjust valve timing and lift is to provide a "lost motion" device or a variable length device in the valve train linkage between a given engine valve and its corresponding cam. Lost motion is a term for a class of technical solutions that utilize a mechanical linkage assembly, a hydraulic linkage assembly, or other linkage assemblies of variable length to modify the valve actuation motion defined by the cam profile. In a lost motion system, the cam lobe can provide the "maximum" motion (longest dwell time and maximum lift) required for various engine operating conditions, including, for example, forward power generation operation and / or auxiliary operation as required in some cases. A variable length system can then be included in the valve train linkage, intermediate the valve to be opened and the cam providing the maximum motion, to reduce or discard some or all of the motion imparted to the valve by the cam. Typically, such lost motion devices can be controlled between a "locked" or motion transmitting state and an "unlocked" or motion absorbing state. During the locked state, the lost motion device maintains a substantially rigid configuration (with a margin for clearance adjustment) such that the valve actuation motion applied to it is transmitted to the corresponding engine valve. On the other hand, during the unlocked state, the lost motion device is enabled to absorb or avoid (i.e., "discard") at least some (up to and including all) of the valve actuation motion applied to it, thereby preventing such valve actuation motion from being transmitted to the corresponding engine valve.

[0005] Valve actuation systems incorporating lost motion functionality continue to be developed to achieve greater valve actuation functionality and flexibility. However, cost, packaging, and size increases are factors that can often determine the desirability of such engine valve actuation systems. A valve actuation system incorporating lost motion components that overcomes these limitations while still diversifying valve actuation functionality and flexibility would be a welcome representative advancement in the art. SUMMARY OF THE INVENTION

[0006] The present disclosure describes various embodiments of a valve actuation system for actuating at least one engine valve in an internal combustion engine. In one embodiment, a system for actuating at least two engine valves associated with a cylinder of an internal combustion engine includes a first rocker arm assembly operatively connected to a first valve actuation motion source and connected to a first engine valve of the at least two engine valves. The first rocker arm assembly includes a first free play member arranged in series with a first input rocker arm and a first output rocker arm, wherein the first input rocker arm is configured to receive a first valve actuation motion from the first valve actuation motion source, and the first output rocker arm is configured to impart the first valve actuation motion to the first engine valve. The first free play member is capable of operating in a motion absorption state to prevent the first valve actuation motion from being transmitted from the first input rocker arm to the first output rocker arm, and is capable of operating in a motion transmission state to transmit the first valve actuation motion from the first input rocker arm to the first output rocker arm. A second rocker arm assembly is operatively connected to a second valve actuation motion source and connected to a second engine valve of the at least two engine valves. The second rocker arm assembly includes at least one second rocker arm configured to receive a second valve actuation motion from the second valve actuation motion source and configured to impart the second valve actuation motion to the second engine valve. The system further includes a one-way coupling mechanism disposed between the first output rocker arm and the at least one second rocker arm such that the second valve actuation motion is transmitted from the at least one second rocker arm to the first output rocker arm, and the first valve actuation motion is not transmitted from the first output rocker arm to the at least one second rocker arm.

[0007] In one embodiment, both or either of the first output rocker arm and / or the at least one second rocker arm includes a hydraulic lash adjuster.

[0008] In one embodiment, the first rocker arm assembly is configured to operate as a type II rocker arm or as a type III rocker arm.

[0009] In one embodiment, each of the first input rocker arm and the first output rocker arm includes an axially-mounted half rocker arm. Further with respect to this embodiment, the first output rocker arm may include a lateral arm defining a central opening configured to receive the first input rocker arm therebetween. In an alternative embodiment, the first output rocker arm and the first input rocker arm are configured to be deployed adjacent to each other.

[0010] In one embodiment, the at least one second rocker arm includes an axially-mounted half rocker arm.

[0011] In one embodiment, the one-way coupling mechanism includes a coupling arm forming a part of the at least one second rocker arm and a coupling contact surface forming a part of the first output rocker arm, and wherein the coupling arm and the coupling contact surface are configured to contact each other.

[0012] In one embodiment, the first floating member includes a hydraulically controlled locking mechanism.

[0013] In another embodiment, at least one second rocker arm includes a second floating member that is arranged in series with a second input rocker arm and a second output rocker arm. The second input rocker arm is configured to receive a second valve actuation motion from a second valve actuation motion source, and the second output rocker arm is configured to impart the second valve actuation motion to a second engine valve. The second floating member can operate in a motion absorption state to prevent the second valve actuation motion from being transmitted from the second input rocker arm to the second output rocker arm, and can operate in a motion transmission state to transmit the second valve actuation motion from the second input rocker arm to the second output rocker arm.

[0014] In one embodiment, the second output rocker arm includes a hydraulic lash adjuster.

[0015] In one embodiment, the second rocker arm assembly is configured to operate as a type II rocker arm. Further with respect to this embodiment, the first rocker arm assembly is also configured to operate as a type II rocker arm.

[0016] In one embodiment, the second rocker arm assembly is configured to operate as a type III rocker arm. Further with respect to this embodiment, the first rocker arm assembly is also configured to operate as a type III rocker arm.

[0017] In one embodiment, each of the second input rocker arm and the second output rocker arm includes an axially mounted half rocker arm. Further with respect to this embodiment, the second output rocker arm includes a lateral arm defining a central opening that is configured to receive the second input rocker arm therebetween. In an alternative embodiment, the second output rocker arm and the second input rocker arm are configured to be deployed adjacent to each other.

[0018] In one embodiment, the one-way coupling includes a coupling arm forming a part of the second output rocker arm and a coupling contact surface forming a part of the first output rocker arm, and wherein the coupling arm and the coupling contact surface are configured to contact each other.

[0019] In one embodiment, the second floating member includes a hydraulically controlled locking mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The foregoing and other features and advantages will be discussed in detail in the following non-limiting description of specific embodiments in conjunction with the accompanying drawings, in which:

[0021] Figure 1 and Figure 2 schematically illustrates an embodiment of a valve actuation system including a floating member in accordance with the present disclosure;

[0022] Figure 3 Is a cross-sectional view of an example of an air-operated component that can be used to implement various embodiments described herein;

[0023] Figure 3A Is a cross-sectional view of an alternative example of an air-operated component that can be used to implement various embodiments described herein;

[0024] Figures 4 to 6 Illustrates a first embodiment of a valve actuation system according to Figure 1 a first embodiment;

[0025] Figure 7 and Figure 8 Illustrates a second embodiment of a valve actuation system according to Figure 2 a second embodiment;

[0026] Figures 9 to 11 Illustrates a third embodiment of a valve actuation system also according to Figure 2 the second embodiment; and

[0027] Figures 12 to 21 is Figures 4 to 6 an embodiment of Figure 7 and Figure 8 an embodiment of Figure 3A a cross-sectional view of an alternative air-operated component employed in an embodiment of Detailed Description

[0028] As used herein, a phrase that is substantially similar to "at least one of A, B, or C" is intended to be interpreted disjunctively, i.e., requiring A or B or C or any combination thereof, unless the context otherwise indicates or implies. Additionally, a phrase that is substantially similar to "at least one of A, B, and C" is intended to be interpreted conjunctively, i.e., requiring at least one of A, at least one of B, and at least one of C, unless the context otherwise indicates or implies. Furthermore, the term "substantially" or similar words that require subjective comparison are intended to mean "within manufacturing tolerances", unless the context otherwise indicates or implies.

[0029] As used herein, the term "operatively connected" is understood to mean at least a functional relationship between two components, i.e., the claimed components must be connected in a manner that performs the indicated function (potentially including the presence of intervening elements or components).

[0030] Figure 1Schematically illustrate a first embodiment of a valve actuation system 100 including a first rocker arm assembly 110 and a second rocker arm assembly 140. As shown, the first rocker arm assembly 110 is operatively connected to a first valve actuation motion source 120, and the second rocker arm assembly 140 is operatively connected to a second valve actuation motion source 150. A first engine valve 162 and a second engine valve 164 (both of which can be, for example, intake valves or exhaust valves) are associated with a cylinder 160 of an internal combustion engine, and these valves 162, 164 are operatively connected to respective rocker arm assemblies of the first rocker arm assembly 110 and the second rocker arm assembly 140. Thus, the first rocker arm assembly 110 and the second rocker arm assembly 140 are operative to actuate (i.e., open and close) the engine valves 162, 164 in accordance with instructions from the first valve actuation motion source 120 and the second valve actuation motion source 150 (and subject to the operation of any incorporated lash components), as described in more detail below. Although Figure 1 only a single cylinder 160 is illustrated, it should be understood that an internal combustion engine can include more than one cylinder, and the valve actuation system described herein can be applied to any number of cylinders of a given internal combustion engine.

[0031] The valve actuation motion sources 120, 150 can include any combination of elements such as cams that are capable of providing valve actuation motion. Each of the valve actuation motion sources 120, 150 can be dedicated to providing main exhaust motion, main intake motion, auxiliary motion, or a combination of main exhaust or main intake motion and auxiliary motion. For example, in one embodiment, the first motion source 120 is configured to provide auxiliary valve actuation motion, and the second motion source 150 is configured to provide main valve actuation motion (either exhaust or intake).

[0032] In a first embodiment, a first rocker arm assembly 110 includes a first input rocker arm 112, a first floating member 114, and a first output rocker arm 116 arranged in series. As used herein, the phrase "in series" is with respect to the conveyance of valve actuation motion, i.e., the degree to which the respective components are in series such that they convey valve actuation motion from one to another along a path from a valve actuation motion source to one or more engine valves. Specifically, the first input rocker arm 112 is operatively connected to a first valve actuation motion source 120 and the first output rocker arm 116 is operatively connected to a first engine valve 162, wherein the first floating member 114 is operatively connected to the first input rocker arm 112 and the first output rocker arm 116 and is disposed therebetween. The first input rocker arm 112 and the first output rocker arm 116 may include center pivot rocker arms or type III rocker arms, and various embodiments based on center pivot rocker arms are described in more detail below. However, it should be understood that end pivot rocker arms or type II rocker arms may also be used to implement the first input rocker arm 112 and the first output rocker arm 116. Optionally (as shown in dashed lines), a first hydraulic lash adjuster (HLA) 118 may be included in the first rocker arm assembly 110. In the illustrated example, the first HLA 118 is disposed in the first output rocker arm 116, which may include a hydraulic passage (known in the art; not shown) adapted to supply hydraulic fluid to the first HLA 118. It should be understood that the first HLA 118 may alternatively be disposed as part of other components 112, 114 that make up the first rocker arm assembly 110.

[0033] As Figure 1 Further depicted, an engine controller 180 may be provided and operatively connected to the first floating member 114. The engine controller 180 may include any electronic control device, mechanical control device, hydraulic control device, electro-hydraulic control device, or other type of control device for controlling the operation of the floating mechanism 114, i.e., switching between its respective locked and unlocked states as described above. For example, the engine controller 180 may be implemented by a microprocessor and a corresponding memory storing executable instructions for implementing the desired control functions, including those described below known in the art. It should be understood that other functionally equivalent embodiments of the engine controller 180 may be equivalently employed (e.g., a suitably programmed application specific integrated circuit (ASIC), etc.). Additionally, the engine controller 180 may include a peripheral device located intermediate the engine controller 180 and the first floating member 114 that enables the engine controller 180 to control the operating state of the floating device 114. For example, in the case where the floating device 114 is a hydraulically controlled mechanism (i.e., responsive to the absence or application of hydraulic fluid to an input), such a peripheral device may include a suitable solenoid.

[0034] As Figure 1 shown, the control of the first air-moving component 114 by the engine controller 180 is provided directly to the first air-moving component 114. However, in practice, such control may be implemented via a path through at least one of the adjacent input rocker arm 112 or output rocker arm 116. For example, in the various embodiments described herein, such control is implemented under the control of the engine controller 180 by using hydraulic fluid supplied via one or more fluid channels formed in either the first input rocker arm 112 or the first output rocker arm 116. However, as will be understood by those skilled in the art, other types of control schemes may be equivalently employed to achieve this purpose.

[0035] As Figure 1 further shown, the second rocker assembly 140 includes a second rocker arm 146 that is operatively connected to the second valve actuation motion source 150 and connected to the second engine valve 164. Again, an optional second HLA 148 may be included in the second rocker assembly 140. In the illustrated example, the second HLA 148 is deployed in the second rocker arm 146, which may include a hydraulic passage (not shown) adapted to supply hydraulic fluid to the second HLA 148. It should be noted that since the second rocker assembly 140 does not include an air-moving component, it may not be necessary to ensure the controlled operation (i.e., stroke limitation) of the first HLA 118 as described above.

[0036] A feature of the illustrated first embodiment is the provision of a one-way coupling (OWC) 170 between the second rocker arm 146 of the second rocker assembly 140 and the first output rocker arm 116 of the first rocker assembly 110. The second rocker arm 146 is capable of driving the first output rocker arm 116, but not vice versa, as Figure 1 shown by the one-way arrows between the second rocker arm 146, the one-way coupling 170, and the first output rocker arm 116. That is, there is a one-way coupling 170 such that the valve actuation provided by the second valve actuation motion source 150 can be applied to the first output rocker arm 116, while the valve actuation provided by the first valve actuation motion source 120 cannot be applied to the second rocker arm 146. In one embodiment, the one-way coupling 170 is implemented using a fixed element such that the one-way coupling 170 is "always there", i.e., the one-way coupling 170 is not selectable. However, it should be understood that selectable elements such as a hydraulically controlled actuator may also be used to implement the one-way coupling 170.

[0037] As Figure 1In the configuration shown, the valve actuation system 100 provides various options for actuating engine valves 162, 164. For example, in a case where the second valve actuation motion source 150 provides the primary valve actuation motion and the first valve actuation motion source 120 provides the auxiliary valve actuation motion, the first idle member 114 can be controlled to be in its unlocked state or motion absorbing state such that the auxiliary valve actuation motion applied to the first input rocker 112 is not transmitted by the first idle member 114 to the first output rocker 116 or thus to the first engine valve 162. In this case, the primary valve actuation motion applied to the second rocker 146 is applied to the second engine valve 164. Additionally, by means of the one-way coupling 170, the primary valve actuation motion applied to the second rocker 146 is also applied to the first output rocker 116 and thus to the first engine valve 162. Such control of the engine valves 162, 164 can be utilized to, for example, implement the forward power generation operation of the engine.

[0038] On the other hand, the first idle member 114 can be controlled to be in its locked state or motion transmitting state such that the auxiliary valve actuation motion applied to the first input rocker 112 is transmitted by the first idle member 114 to the first output rocker 116 and thus to the first engine valve 162. In this case, the second rocker 146 and the one-way coupling 170 will continue to operate as described above, with the result that the primary valve actuation motion will be provided to both the first engine valve 162 and the second engine valve 164, while the auxiliary valve actuation motion will be provided only to the first engine valve 162. Such control of the engine valves 162, 164 can be utilized to implement, for example, the conventional 4-stroke, compression release engine braking operation of the engine, or to provide other additional auxiliary valve actuation motions of the above type.

[0039] Now referring to Figure 2 , a second embodiment of a valve actuation system 200 including a first rocker assembly 110 and a second rocker assembly 240 is shown. Figure 2 The valve actuation system 200 of Figure 1 differs from the valve actuation system 100 of Figure 2Components of the second rocker arm assembly 240. More specifically, the second rocker arm assembly 240 includes a second input rocker arm 242, a second floating member 244, and a second output rocker arm 246 arranged in series. Specifically, the second input rocker arm 242 is operatively connected to the second valve actuation motion source 150, and the second output rocker arm 246 is operatively connected to the second engine valve 162, wherein the floating member 244 is operatively connected to the second input rocker arm 242 and the second output rocker arm 246 and is disposed therebetween. The second input rocker arm 242 and the second output rocker arm 246 may include center pivot rocker arms, and various embodiments based on the center pivot rocker arms are described in more detail below. Again, it should be understood that end pivot rocker arms or type II rocker arms may also be used to implement the first input rocker arm 112 and the first output rocker arm 116. Optionally, a second hydraulic lash adjuster (HLA) 248 may be included in the second rocker arm assembly 240. In the illustrated example, the second HLA 248 is disposed in the second output rocker arm 246, which may include a hydraulic passage (not shown) adapted to supply hydraulic fluid to the second HLA 248. It should be understood that the second HLA 248 may alternatively be disposed as part of other components 242, 244 that make up the second rocker arm assembly 110. Similar to the first HLA 118 in the first embodiment, in the presence of the second floating member 244 in the second rocker arm assembly 240, it may be desirable to control the operation of the second HLA 248 to prevent the second engine valve 164 from overextending. Alternatively, again, in this case, by incorporating a stroke limit into the second floating member 244 and a biasing force supplied by the first floating member 224 sufficient to prevent the HLA 248 from overextending, the overextension of the engine valve may be prevented by the operation of the HLA 248 instead.

[0040] In the case where the second floating member 244 is added to the second rocker arm assembly 240, the controller 280 in the second embodiment is substantially the same as the controller 180 in the first embodiment, except that the controller 280 is modified to also be operatively coupled to the second floating member 244. Again, although the controller 280 is illustrated as directly controlling the second floating member 244, it should be understood that such control may be facilitated through a path provided in an adjacent component such as the second input rocker arm 242 and / or the second output rocker arm 246, for example.

[0041] In addition to this, except as Figure 2 shown, a one-way coupling 270 is disposed between the second output rocker arm 246 and the first output rocker arm 116, the operation of the one-way coupling 270 in the second embodiment is substantially the same as the operation of the one-way coupling 170 in the first embodiment.

[0042] As Figure 2In the illustrated configuration, valve actuation system 100 provides various options for actuating engine valves 162, 164. For example, again, in the case where second valve actuation motion source 150 provides primary valve actuation motion and first valve actuation motion source 120 provides auxiliary valve actuation motion, first idle member 114 can be controlled to be in its unlocked state or motion absorbing state such that the auxiliary valve actuation motion applied to first input rocker 112 is not transmitted by first idle member 114 to first output rocker 116 or thus not transmitted to first engine valve 162. Additionally, second idle member 244 can be controlled to also be in its unlocked state or motion absorbing state such that the primary valve actuation motion applied to second input rocker 242 is not transmitted by second idle member 244 to second output rocker 246, or thus not transmitted to second engine valve 164 (or not transmitted to first engine valve by means of one-way coupling 270). Such control of engine valves 162, 164 can be utilized, for example, to effect cylinder deactivation (CDA) operation of the engine.

[0043] Alternatively, based on the same example where first idle member 114 again operates in its unlocked / motion absorbing state and second idle member 244 operates in its locked / motion transmitting state, the auxiliary valve actuation motion is not transmitted to first engine valve 162, while the primary valve actuation motion is transmitted to both first valve 162 and second valve 164. Such control of engine valves 162, 164 can be utilized, for example, to effect positive power generation operation of the engine.

[0044] In another alternative, based on the same example where first idle member 114 operates in its locked / motion transmitting state and second idle member 244 operates in its locked / motion transmitting state, the auxiliary valve actuation motion is transmitted to first engine valve 162 and the primary valve actuation motion is transmitted to both first valve 162 and second valve 164. Such control of engine valves 162, 164 can be utilized to effect, for example, conventional 4-stroke, compression release engine braking operation of the engine, or to provide other additional auxiliary valve actuation motions of the type described above.

[0045] In yet another alternative, based on the same example where the first air moving member 114 operates in its locked state / motion transmission state and the second air moving member 244 operates in its unlocked state / motion absorption state, the auxiliary valve actuation motion is transmitted to the first engine valve 162, while the main valve actuation motion is not transmitted to the first valve 162 or the second valve 164. Such control of the engine valves 162, 164 can be utilized to achieve a working mode where the desired auxiliary valve actuation is present but the desired main valve actuation is not. For example, such working modes can include the so-called 2-stroke or 1.5-stroke, compression release engine braking operations of the engine.

[0046] Figure 3 An example of an air moving member 300 is illustrated, which can be used in conjunction with Figure 1 and Figure 2 the valve actuation systems 100, 200 shown and the various specific embodiments described below regarding Figures 4 to 11 is shown in cross-section to better illustrate the hydraulically controlled locking mechanism 310, which forms a sub-assembly of the air moving member 300 and is deployed between the housing 320 and the plunger 322. Although the housing 320 can be formed as a single element, in the Figure 3 example shown, the closed end of the housing 320 is provided by an end cap 321 attached to the housing 320. The plunger spring 324 is deployed outside the housing 320 and the plunger 322. In the illustrated embodiment, the plunger spring 324 is deployed between a flange 326 formed on or attached to the outer surface of the plunger 322 and a shoulder 328 formed in the housing 320. In this way, the plunger spring 324 biases the housing 320 and the plunger 322 away from each other. In one embodiment, the biasing force applied by the plunger spring 324 is high enough to prevent any hydraulically actuated lash adjuster deployed within the same valve mechanism as the air moving member 300 from extending. Additionally, although the plunger spring 324 is deployed outside the housing 320 in the illustrated example, it should be understood that the plunger spring 324 can also be disposed within the housing 320 such that it achieves a similar biasing as described above.

[0047] As described, the plunger spring 324 is strong enough to prevent any hydraulically actuated lash adjuster deployed within the same valve mechanism as the air moving member 300 from extending. However, if the biasing force of the plunger spring 324 is too strong, this may cause the hydraulically actuated lash adjuster to fail. To prevent this from occurring, a stroke limit for the air moving member 300 can be provided to prevent the housing 320 and the plunger 322 from extending too far away from each other, as otherwise such over-extension may apply a compressive force to the hydraulically actuated lash adjuster sufficient to cause it to fail. For example, although not shown in Figure 3However, the end of the plunger 322 near the plunger cap 343 may include a radially extending lip or flange configured to engage a shoulder 331 formed in the surface defining the housing aperture 330. Thus, when the plunger spring 324 biases the plunger 322 out of the housing 320, the engagement of the radially extending lip or flange with the shoulder 331 prevents the plunger 322 from further traveling out of the housing 320. By restricting the travel of the plunger 322, the floating member 300 is prevented from applying an excessive compressive force to any of the component hydraulic lash adjusters in the valve train, thereby preventing the hydraulic lash adjuster from failing.

[0048] As Figure 3 shown, the locking mechanism 310 includes a plunger 322 disposed within a housing aperture 330 that is formed in and extends along the longitudinal axis of the floating member 300 from a first end of the housing 320. An inner plunger 332 is slidably disposed within a longitudinal aperture 334 formed in the plunger 322. An inner plunger spring 342 is disposed between the inner plunger 342 and the plunger cap 343 and thus tends to bias the inner plunger out of the aperture 334. A locking element in the form of a wedge 336 is provided and is configured to engage an annular outer recess 338 formed in the surface defining the housing aperture 330. The illustrated embodiment is a locking mechanism 310 that is normally locked, i.e., in the absence of hydraulic control applied to the inner plunger 332 via (in this case) the floating hydraulic passage 340, the inner plunger spring 342 biases the inner plunger 332 into a proper position such that the wedge 336 extends radially out of an opening formed in the plunger 320, thereby engaging the outer recess 338 and effectively locking the plunger 322 in a proper position relative to the housing 320.

[0049] In this locked state, any valve actuation movement (whether primary or secondary) applied to either end of the floating member 300 is transmitted by the floating member 300. It should be noted that although in the locked state as Figure 3 shown, the longitudinal extent of the outer recess 338 is still greater than the thickness of the wedge 336 such that a small amount of movement is still possible between the plunger 322 and the housing 320. Such additional space provided by the outer recess 338 facilitates locking / unlocking the locking mechanism 310 when the floating member 300 is unloaded. As Figure 3 shown, for example, in the case where valve actuation movement has been applied to the floating member 300 to overcome any outward biasing applied to the plunger 322 by the plunger spring 324, this additional space has been occupied.

[0050] The bias applied by the plunger spring 324 can be selected to additionally ensure that adjacent valve train components 352, 354 (or such additional upstream or downstream valve train components in the system, not shown) are biased into continuous contact with the respective endpoints of the valve train (i.e., the valve actuation motion source and the engine valve). For example, as described in more detail below, the input rocker arm and the output rocker arm are arranged in series with the floating member within the rocker arm assembly. In this case, the plunger spring 324 of the floating member can apply a biasing force to the input rocker arm and the output rocker arm to ensure that such input rocker arm is biased into contact with the valve actuation motion source and / or such output rocker arm is biased towards the respective engine valve, thereby fully loading any constituent hydraulic lash adjuster to prevent its excessive expansion.

[0051] Referring again Figure 3 , hydraulic fluid is provided to the input receiving end of the inner plunger 332 via the floating hydraulic passage 340 (such as the bottommost surface as Figure 3 shown), and the hydraulic fluid is sufficiently pressurized to overcome the bias of the inner piston spring 342, causing the inner plunger 332 to translate within the orifice 334 such that the wedge portion 336 can retract from and disengage from the outer recess 338, thereby effectively unlocking the plunger 322 relative to the housing 320 and enabling the plunger 322 to slide freely within its orifice 330, in which case, it is subjected to the bias provided by the plunger spring 324. In this unlocked state, any valve actuation motion applied to the floating member 300 will cause the plunger 322 to reciprocate within its orifice 330. Thus, and assuming that the stroke of the plunger 322 within its orifice 330 is greater than the maximum range of any applied valve actuation motion (i.e., the plunger 322 cannot reach the lowest point within its orifice 330), such valve actuation motion is not transmitted by the floating member 300 and is effectively discarded. Alternatively, the stroke of the plunger 322 within its orifice 330 can be configured such that the plunger 322 "reaches the lowest point", i.e., contacts the closed end of the orifice 330, in order to always provide "fail-safe" valve lift in the event of a failure of the locking mechanism 310.

[0052] Although Figure 3 illustrating a specific embodiment and construction of the floating member 300, it should be understood that other constructions can be equivalently employed and the present disclosure is not limited in this regard. For example, as previously described, the illustrated floating member 300 is a normally locked floating assembly. However, as should be understood by those skilled in the art, a floating member of the normally unlocked type can be equivalently employed.

[0053] Figure 3A An example of a floating member 300' that is normally unlocked is illustrated. In Figure 3 and Figure 3A , elements with similar reference numerals are substantially similar in structure and function, while Figure 3AReference numerals in the figures that include an apostrophe (') refer to elements that are characterized by having a structure and / or function different from that of the corresponding element shown in Figure 3 as described below. In the embodiment shown in Figure 3A the floating member 300' again includes a housing 320 having a longitudinal aperture 330 formed therein and a plunger 322' slidably disposed in the aperture 330. Similarly, an inner plunger 332' is disposed in an aperture 334' formed in the plunger 332' and is biased out of the aperture 334' by an inner plunger spring 342 disposed between the inner plunger 322' and a plunger cap 343.

[0054] However, in this case, the inner plunger 332' is configured to be substantially opposite to the inner plunger 332 shown in Figure 3 such that in the absence of hydraulic control being applied to the inner plunger 332', the inner plunger spring 342 biases the inner plunger 332' into a proper position such that the wedge portion 336 does not radially extend out of an opening formed in the plunger 320 and thus does not engage an outer annular groove 338', thereby effectively unlocking the plunger 322' relative to the housing 320 and allowing the plunger 322' to freely slide within its aperture 330, subject to the bias provided by a plunger spring 324. In this unlocked state, any valve actuation movement applied to the floating member 300' will cause the plunger 322' to reciprocate within its aperture 330. In the illustrated embodiment, the plunger 322' is configured such that the stroke of the plunger 322' within its aperture 330 allows the plunger 322' to "bottom out", i.e., in this case, contact is formed between the plunger cap 343 and the closed end of the aperture 330. Thus, the floating member 300' is capable of preventing any hydraulic lash adjuster disposed in the same valve mechanism as the floating member 300' from overextending. Additionally, such a stroke limitation of the plunger 322' allows for the application of a "fail-safe" auxiliary valve actuation movement, e.g., a high-lift brake gas recirculation (BGR) movement, in the event of a failure of the locking mechanism 310. Again, a stroke limitation of the floating member 300' may be provided in order to prevent the housing 320 and the plunger 322' from overextending away from each other, which otherwise could cause the hydraulic lash adjuster to fail. For example, as shown in Figure 3A the plunger cap 343 may be configured such that it includes a radially extending lip or flange 333 that is configured to engage a shoulder 331 formed in the aperture 330, thereby preventing the plunger 322' from overextending out of the aperture 330.

[0055] On the other hand, at the input receiving end of the inner plunger 332' (as shown in Figure 3AThe bottom surface shown) provides hydraulic fluid that is pressurized sufficiently to overcome the bias of the inner piston spring 342, causing the inner plunger 332' to translate within the orifice 334 such that the wedge portion 336 is forced to extend and engage the outer recess 338', thereby effectively locking the plunger 322' relative to the housing 320. In this locked state, an actuating movement of the valve applied to the floating member 300' will cause the plunger 322' to engage the housing 320, thereby transmitting such valve actuating movement.

[0056] Another feature of the housing 320 is that the annular outer recess 338' has a longitudinal extent such that the plunger 322' can slide within its orifice 330 even when the floating member 300' is in its locked / movement - transmitting state. As described in more detail below, during the operating state where the first output rocker 116 is controlled by the second rocker 146 / second output rocker 246 and the intermediate one - way couplings 170, 270, this configuration of the outer recess 338' accommodates the separation between the first input rocker 112 and the first output rocker 116.

[0057] Now referring to Figures 4 to 6 , there is shown a first embodiment of a valve actuating system according to Figure 1 . Specifically, the embodiment shown includes a first rocker assembly 402 and a second rocker assembly 404. The first rocker assembly 402 includes a first input rocker 406, a first output rocker 408, and a floating member 410. The first input rocker 406 includes a roller bearing 407 that is configured to receive valve actuating movement from a first valve actuating movement source, such as a cam disposed on an overhead camshaft (not shown), at the movement receiving end of the first input rocker 406. The movement applying end of the first input rocker 406 is operatively connected to the input end of the first floating member 410. In turn, the output end of the first floating member 410 is operatively connected to the movement receiving end of the first output rocker 408. In one embodiment, the first input rocker 406 may include one or more hydraulic channels (not shown) that are configured to receive hydraulic fluid from, for example, a rocker shaft (not shown) and direct such hydraulic fluid to the first floating member 410 (thereby controlling its operation as described above with respect to Figure 3 ).

[0058] In the present embodiment, the first output rocker arm 408 includes a pair of lateral arms 412, 414 that define a central opening 416 therebetween, which central opening 416 is configured to receive the first input rocker arm 406 such that the first input rocker arm 406 is surrounded or embraced between the lateral arms 412, 414. In the present embodiment, the first output rocker arm 408 also includes a hydraulic lash adjuster 420 that is configured to be operatively connected to a first engine valve (not shown). According to known techniques, the first output rocker arm 408 also includes one or more internal hydraulic passages (not shown) that are configured to receive hydraulic fluid from, for example, a rocker shaft (not shown) and direct such hydraulic fluid to the hydraulic lash adjuster 420.

[0059] As Figure 4 best shown, the first output rocker arm 408 includes rocker shaft apertures 418 formed in both of the lateral arms 412, 414, which rocker shaft apertures are configured to receive a rocker shaft. Additionally, although not shown in Figures 4 to 6 it, the first input rocker arm 406 also includes a rocker shaft aperture that is configured to receive a rocker shaft. Constructed in this manner, both the first input rocker arm 406 and the first output rocker arm 408 are capable of reciprocating about the rocker shaft in response to valve actuation movement being applied to the first input rocker arm 406 (and via the first idle member 410 to the output rocker arm 408) or, as explained in more detail below, in response to valve actuation movement being applied to the first output rocker arm 408 via the second rocker assembly 404.

[0060] It should be noted that, from the perspective of the first valve actuation motion source (applying valve actuation movement to the first input rocker arm 406) and the first engine valve (receiving the valve actuation movement of the first output rocker arm 408), the first rocker assembly 402 operates in a manner similar to a type II rocker or an end pivoted rocker, much like a so-called finger follower known in the art. However, to achieve such an operating mode, the first rocker assembly 402 relies on a combination of two type III rockers or center pivoted rockers (the first input rocker arm 406 and the first output rocker arm 406) used in conjunction with the first idle assembly 410. That is, the first rocker assembly 402 can be regarded as a quasi-type II rocker or a composite type II rocker based on a combination of component type III rockers.

[0061] In the present embodiment, the second rocker assembly 404 includes a second rocker arm 422. As Figure 5 and 6As best shown, in the present embodiment, the second rocker arm 422 is a shaft-mounted end pivot rocker arm or a type II rocker arm, which includes a rocker arm shaft orifice 424 that is configured to receive a rocker arm shaft. As shown, the second rocker arm assembly 404 is placed adjacent to the first rocker arm assembly 402, and more specifically, the second rocker arm 422 is disposed on a rocker arm shaft adjacent to the first output rocker arm 408. The second rocker arm 422 also includes a roller bearing 423 that is configured to receive valve actuation motion from a second valve actuation motion source, such as a cam disposed on an overhead camshaft. In the present embodiment, the second rocker arm 422 also includes a hydraulic lash adjuster 426 that is configured to be operatively connected to a second engine valve (not shown). According to known techniques, like the first output rocker arm 408, the second rocker arm 422 also includes one or more internal hydraulic channels (not shown) that are configured to receive hydraulic fluid from, for example, the rocker arm shaft and direct such hydraulic fluid to the hydraulic lash adjuster 426. Constructed in this manner, the second rocker arm 422 is capable of reciprocating about the rocker arm shaft in response to valve actuation motion applied by the second valve actuation motion source and transmitting such valve actuation motion to the second engine valve.

[0062] As Figure 4 and Figure 5As best shown, a one-way coupling 430 is provided between the second rocker arm 422 and the first output rocker arm 408. In the present embodiment, the one-way coupling 430 is formed by a combination of a coupling arm 432 and a coupling contact surface 434 that are respectively provided at the motion application ends of the second rocker arm 422 and the first output rocker arm 408. The coupling arm 432 is integrally formed in the second rocker arm 422 and extends toward the first output rocker arm 408. The upward-facing coupling contact surface 434 is integral with and aligned with the first output rocker arm 434 so as to form contact (but not lock or fasten thereto) with the downward-facing surface of the coupling arm 432. In this way, the valve actuation motion applied to the second rocker arm 422 is transmitted to the first output rocker arm 408, while the valve actuation motion applied to the first output rocker arm 408 via the first input rocker arm 406 and the first idle member 410 is not transmitted to the second rocker arm 422. Although in the illustrated embodiment, the component elements of the one-way coupling 430 are provided at the motion application ends of the second rocker arm 422 and the first output rocker arm 408, it should be understood that the one-way coupling 430 can be provided at various positions between the respective rocker arms. Additionally, although the contact surfaces provided by the coupling arm 432 and the coupling contact surface 434 are illustrated as fixed surfaces, it should be understood that such surfaces can be made into selectable surfaces, such as in the case of using an adjustable clearance screw or the like. In addition to this, it should be understood that two coupling arms can be used to construct the one-way coupling 430, the two coupling arms extending toward each other and having overlapping contact surfaces, such as in the case where the first rocker arm assembly 402 and the second rocker arm assembly 404 are not positioned adjacent to each other, which may be necessary.

[0063] Now referring to Figure 7 and Figure 8 , there is shown a second embodiment of a valve actuation system according to Figure 2 . Consistent with Figure 2 , Figure 7 and Figure 8 the embodiment shown includes a first rocker arm assembly 402 and an adjacent second rocker arm assembly 704. Figure 7 and Figure 8 The first rocker arm assembly 402 shown in Figures 4 to 6 is substantially the same in function and structure as the first rocker arm assembly 402 shown in Figure 2 , as indicated by similar reference numerals. However, consistent with Figures 4 to 6The second rocker arm assembly 404 shown is more complex. In this case, the second rocker arm assembly 704 includes a second input rocker arm 706, a second output rocker arm 708, and a second floating member 710. The second input rocker arm 706 includes a roller bearing 707 configured to receive valve actuation motion from a second valve actuation motion source such as a cam (not shown) provided on an overhead camshaft (not shown) at a motion receiving end of the second input rocker arm 706. A motion application end of the second input rocker arm 706 is operatively connected to an input end of the second floating member 710. Subsequently, an output end of the second floating member 710 is operatively connected to a motion receiving end of the second output rocker arm 708. In one embodiment, the second input rocker arm 706 may include one or more hydraulic channels (not shown) configured to receive hydraulic fluid from, for example, a rocker shaft (not shown) and direct such hydraulic fluid to the second floating member 710 (thereby controlling its operation as described above with respect to Figure 3 ). The second output rocker arm 708 substantially includes paired side arms 712, 714 as in the first output rocker arm 408, the paired side arms defining a central opening 716 therebetween, the central opening 716 being configured to receive the second input rocker arm 706 such that the second input rocker arm 706 is surrounded or embraced between the side arms 712, 714.

[0064] Unlike Figures 4 to 6 the embodiment of, the first output rocker arm 408 and the second output rocker arm 708 each include a lash screw and a pivot (or electronic foot) assembly 720, 740 provided at motion application ends of the first output rocker arm 408 and the second output rocker arm 708, rather than including a hydraulic lash adjuster. However, it should be understood that if either or both of the first output rocker arm 408 and the second output rocker arm 708 are configured to include the necessary hydraulic channels for operating a hydraulic lash adjuster, the corresponding hydraulic lash adjuster can be used to replace one or both of the lash screw and the pivot assembly 720, 740.

[0065] As Figure 8 best shown, the second output rocker arm 708 includes rocker shaft apertures 718 formed in both of the side arms 712, 714, the rocker shaft apertures being configured to receive a rocker shaft. Additionally, although not shown in Figure 7 and Figure 8However, the second input rocker arm 706 also includes a rocker shaft port that is configured to receive a rocker shaft. Constructed in this manner, both the first input rocker arm 706 and the first output rocker arm 708 are capable of reciprocating about the rocker shaft in response to valve actuation motion being applied to the first input rocker arm 406 (and via the first idle member 410 to the first output rocker arm 408) or in response to valve actuation motion being applied to the first output rocker arm 408 via the second rocker assembly 704 and the one-way coupling 730.

[0066] As with Figures 4 to 6 the embodiment shown, the second rocker assembly 704 is placed adjacent to the first rocker assembly 402, and more specifically, the second output rocker arm 708 is disposed on a rocker shaft adjacent to the first output rocker arm 408. The second input rocker arm 706 also includes a roller bearing 707 that is configured to receive valve actuation motion from a second valve actuation motion source such as a cam disposed on an overhead camshaft. Constructed in this manner, the second input rocker arm 706 and (in combination with the second idle member 710) the second output rocker arm 708 are capable of reciprocating about the rocker shaft in response to the second valve actuation motion source applying valve actuation motion to the second input rocker arm 706.

[0067] As Figure 7 best shown, a one-way coupling 730 is disposed between the second output rocker arm 708 and the first output rocker arm 408. In the present embodiment, the one-way coupling 730 is formed by a combination of a coupling arm 732 disposed at the motion application end of the second output rocker arm 708 and the aforementioned coupling contact surface 434, respectively. In this case, the coupling arm 732 is integrally formed in the second output rocker arm 708 and extends toward the first output rocker arm 408. Again, the upward-facing coupling contact surface 434 is integral with and aligned with the first output rocker arm 434 so as to form contact (but not lock or fasten thereto) with the downward-facing surface of the coupling arm 732. Thus, the valve actuation motion applied to the second output rocker arm 708 (via the second input rocker arm 706 and the second idle member 710) is transmitted to the first output rocker arm 408, while the valve actuation motion applied to the first output rocker arm 408 via the first input rocker arm 406 and the first idle member 410 is not transmitted to the second output rocker arm 732. Again, the Figures 4 to 6 variant of the one-way coupling 430 shown can be equivalently applied to Figure 7 and Figure 8 the one-way coupling 730 shown.

[0068] As will be understood by those skilled in the art, Figures 4 to 8The embodiments of the rocker arm assemblies 402, 404, 704 effectively enable each rocker arm assembly to perform end pivoting or type II operation. As is known in the art, a type II rocker arm utilizes a rocker arm that pivots about one of its ends and applies valve actuation motion at its other end, where a force or valve actuation force is applied to the rocker arm at a midpoint between the pivot end and the load application end. Thus, in Figures 4 to 8 the embodiments, each of the rocker arm assemblies 402, 404, 704 exhibits behavior similar to type II because the assembly rotates or pivots about a rocker shaft and applies valve actuation motion at opposite ends of the assembly, where the assembly receives at least some of the valve actuation motion from a valve actuation motion source applied between its pivot end point and its motion application end point.

[0069] Now referring to Figures 9 to 11 , there is shown a second embodiment of a valve actuation system according to Figure 2 . Consistent with Figure 2 , Figures 9 to 11 the embodiment shown includes a first rocker arm assembly 902 and an adjacent second rocker arm assembly 904. Functionally, Figures 9 to 11 the embodiment shown is substantially the same as Figure 7 and Figure 8 the embodiments shown because the first rocker arm assembly 902 includes a first input rocker 906, a first output rocker 908, and a first intermediate floating member 910 operatively connected to the first input rocker 906 and the first output rocker 908, and the second rocker arm assembly 904 includes a second input rocker 912, a second output rocker 914, and a second intermediate floating member 916 operatively connected to the second input rocker 912 and the second output rocker 914. As Figure 10 and Figure 11 best shown, the illustrated input rockers 906, 912 and output rockers 908, 914 each include respective vertically extending protrusions 940, 942, 944, 946 that are configured to receive corresponding ends of the first floating member 910 and the second floating member 916, as shown. In this case, a hydraulic fluid supply for controlling the operation of the respective floating members 910, 916 can be provided through suitable hydraulic channels (not shown) formed in any one of the input rockers 906, 912 and output rockers 908, 914 and their corresponding protrusions 940, 942, 944, 946.

[0070] In this embodiment, all of the illustrated input rockers 906, 912 and output rockers 908, 914 are shaft-mounted semi-rockers. As Figure 9 and Figure 10As best shown separately, the second output rocker arm 914 and the first output rocker arm 908 each include rocker arm shaft openings 924, 924, which enable the respective output rocker arms 908, 914 to reciprocate about the rocker arm shaft. Although not shown in Figure 9 or Figure 10 , the input rocker arms 906, 912 each include similar rocker arm shaft openings, which enable the respective input rocker arms 906, 912 to reciprocate about the rocker arm shaft. As Figure 10 best shown, the respective input rocker arms 906, 912 each include roller bearings 907, 913, which are used to receive valve actuation motion from respective first valve actuation motion sources and second valve actuation motion sources (not shown), such as cams on a camshaft. In addition, as Figure 9 best shown, the respective output rocker arms 908, 914 each include clearance adjustment screws and swivel assemblies 930, 932 similar to those of the Figure 7 and Figure 8 illustrated embodiment. However, again it should be understood that a hydraulic clearance adjuster may be used instead of either or both of the clearance adjustment screws and swivel assemblies 930, 932, provided that the corresponding first output rocker arm 908 and / or second output rocker arm 914 includes one or more hydraulic channels configured to supply hydraulic fluid to such a clearance adjuster.

[0071] As Figure 11 (wherein, in a top view, the first floating member 910 and the second floating member 916 have been removed to better illustrate the rocker arms 906, 908, 912, 914) best shown, the present embodiment is characterized in that, different from the embodiment in which the input rocker arms 406, 706 of Figure 7 and Figure 8 are nested within their corresponding output rocker arms 408, 708, the input rocker arms 906, 912 are arranged side by side with their corresponding output rocker arms 908, 914.

[0072] It should be noted that, from the perspective of the valve actuation motion source (applying valve actuation motion to the first input rocker arm 906 and the second input rocker arm 912) and the first engine valve and the second engine valve (receiving valve actuation motion from the first output rocker arm 908 and the second output rocker arm 914), the first rocker arm assembly 902 and the second rocker arm assembly 904 operate in a manner similar to that of a type 3 rocker or a center pivot rocker, as is known in the art. In this case, in order to achieve such an operating mode, the first rocker arm assembly 902 and the second rocker arm assembly 904 each rely on two type 3 rockers / center pivot rockers used in combination with the corresponding first idle motion assembly 910 and the second idle motion assembly 916. That is, the first rocker arm assembly 902 and the second rocker arm assembly 904 can be regarded as quasi-type 3 rockers or composite type 3 rockers based on the combination of component type 3 rockers.

[0073] In addition, a one-way coupling 930 is provided between the first rocker arm assembly 902 and the second rocker arm assembly 904. However, in the present embodiment, the one-way coupling 918 includes paired coupling arms 920, 922. In this case, the first coupling arm 920 is integrally formed in the first output rocker arm 908 and extends towards the second output rocker arm 914, while the second coupling arm 922 is integrally formed in the second output rocker arm 914 and extends towards the first output rocker arm 908. The extensions of the first coupling arm 920 and the second coupling arm 922 result in their having overlapping contact surfaces, where the downward-facing contact surface of the second coupling arm 922 faces the upward-facing contact surface of the first coupling arm 920, as Figure 9 best shown. Constructed in this way, the first rocker arm assembly 902, the second rocker arm assembly 904, and the one-way coupling 918 operate in a manner Figure 7 and Figure 8 substantially the same as the first rocker arm assembly 402, the second rocker arm assembly 704, and the one-way coupling 730 shown.

[0074] As those skilled in the art should understand, compared with the embodiment shown in Figures 4 to 8 , the embodiments of the rocker arm assemblies 902, 904 in Figures 9 to 11 effectively enable each rocker arm assembly to perform center pivot or type III operation. As is known in the art, a type III rocker utilizes a rocker that pivots about an intermediate point while receiving a force or valve actuation motion at one end and applying such valve actuation motion at the other end. Therefore, in the embodiment of Figures 9 to 11 , the rocker arm assemblies 902, 904 each exhibit behavior similar to that of a type III because the assemblies rotate or pivot about a rocker shaft while receiving at least some valve actuation motion at one end of the assembly and applying such valve actuation motion at the opposite end of the assembly.

[0075] Figures 12 to 21 is adoptedFigure 3A Cross-sectional view of a valve actuation system of the air-driven component 300'. Specifically, Figures 12 to 21 illustrate Figures 4 to 6 or Figure 7 and Figure 8 Examples of embodiments, but it should be understood that the air-driven component 300' can be equivalently applied to Figures 9 to 11 the embodiments shown. In Figures 12 to 21 the example shown, the first cam that implements the first valve actuation motion source is configured to provide two compression release engine braking valve actuations 1206, 1208 and BGR valve actuation 1210, and the second cam that implements the second valve actuation motion source is configured to provide main exhaust valve actuation 1212, as is known in the art.

[0076] Figure 12 Illustrate the first input rocker 1202 and the first output rocker 1204, wherein the first input rocker 1202 includes a cam roller 1214 configured to receive valve actuation motion from the first valve actuation motion source. Although not shown in Figures 12 to 21 However, a second rocker / second output rocker and a one-way coupling (as described above) are provided and configured to receive valve actuation motion from the second valve actuation motion source and transmit such valve actuation to the first output rocker 1204. As further shown, according to Figure 3A the air-driven component 300' is deployed between the first input rocker 1202 and the first output rocker 1204 and is operatively connected to the first input rocker and the first output rocker.

[0077] Figure 12 Illustrate the case where the air-driven component 300' is in the unlocked state and both the first cam and the second cam are at the base circle. In this state, the plunger spring 324 biases the housing 320 and the plunger 322' freely apart from each other, and in doing so, also biases the first input rocker 1202 into contact with the first cam and biases the first output rocker 1204 into contact with the engine valve (not shown).

[0078] Figures 13 to 15 Illustrate the case where the air-driven component 300' remains in the unlocked state and the first cam applies (i) the peak of the first compression release valve actuation 1206 to the first input rocker 1202, (ii) the peak of the BGR valve actuation 1210 to the first input rocker 1202, and (iii) the peak of the second compression release valve actuation 1208 to the first input rocker 1202. Figure 14 Also shown (via the one-way coupling) is the partial application of the main exhaust valve actuation 1212 applied to the first output rocker 1204. In Figures 13 to 15In each of them, the applied valve actuation causes the plunger 322' to slide within its orifice and causes the plunger spring 324 to compress ( Figure 13 and Figure 15 ) or expand ( Figure 14 ), this compression or expansion being relative to the initial state as shown in Figure 12 . Thus, as previously described, the biasing exerted by the plunger spring 324 ensures continuous contact of the first rocker arm 1202 with the first cam, and continuous contact of the idle member 300' with the first input rocker arm 1202 and the first output rocker arm 1204.

[0079] Figure 16 Illustrated is the case where the idle member 300' remains in the unlocked state and the first cam applies a partial BGR valve actuation 1210 to the first input rocker arm 1202 and the second cam applies the peak of the main exhaust valve actuation 1212 (again, via the one-way coupling) to the first output rocker arm 1204. The result of this situation is that the first output rocker arm 1204 is in the high lift state while the first input rocker arm 1202 is in a relatively low lift state. In this state, the plunger spring 324 freely biases the housing 320 and the plunger 322' to be even further apart from each other, and again, also biases the first input rocker arm 1202 into contact with the first cam and biases the first output rocker arm 1204 into contact with the engine valve (not shown). That is, the idle member 300' can expand to a sufficient extent under the biasing provided by the plunger spring 324 to ensure continuous contact of the idle member 300' with the first input rocker arm 1202 and the first output rocker arm 1204, and to ensure continuous contact of the first input rocker arm 1202 with the first cam.

[0080] Except that the first idle member 300' is maintained in its locked state / motion transfer state, Figure 17 the illustrated state is substantially equivalent to the state shown in Figure 12 . Despite this change in the state of the idle member 300', the plunger spring 324 again freely biases the housing 320 and the plunger 322' to be apart from each other, and in doing so, also biases the first input rocker arm 1202 into contact with the first cam and biases the first output rocker arm 1204 into contact with the engine valve.

[0081] Figures 18 to 21An example is shown where the floating member 300' remains in the locked state and the first cam applies (i) the peak of the first compression release valve actuation 1206 to the first input rocker 1202, (ii) the peak of the BGR valve actuation 1210 to the first input rocker 1202, (iii) the peak of the second compression release valve actuation 1208 to the first input rocker 1202, and (iv) the first cam applies a portion of the BGR valve actuation 1210 to the first input rocker 1202 and the second cam applies the peak of the main exhaust valve actuation 1212 (again, via the one-way coupling) to the first output rocker 1204. Figure 19 Also shown is the partial application of the main exhaust valve actuation 1212 applied to the first output rocker 1204 (via the one-way coupling). In Figures 18 to 21 each of these cases, the applied valve actuation causes the plunger 322' to engage the housing 320 via the interaction of the wedge portion 336 with the upper surface of the annular outer recess 338'. Thus, the various applied valve actuations are applied to the engine valves.

[0082] Although not shown in Figures 17 to 21 depending on the configuration of the first and second cams, there may be a situation where the difference in lift applied to the first input rocker 1202 (via the first cam) and the first output rocker 1204 (via the one-way coupling) will cause a tendency for the plunger 322' and the housing 330 to separate from each other, even though the floating member 300' is in the locked state / motion transmission state. In these cases, even though the floating member 300' is in the locked state, the greater longitudinal length of the annular outer recess 338' still allows the floating member to expand, thus ensuring that the floating member 300' is maintained between the first input rocker 1202 and the first output rocker 1204.

[0083] Although the various embodiments in accordance with the present disclosure have been described in connection with their specific embodiments, it will be apparent that many alternatives, modifications, and variations will be obvious to those skilled in the art. In the various embodiments described herein, the input rocker and the output rocker are depicted as pivoting about a rocker shaft. However, the present disclosure need not be limited in this regard, and it should be understood that pivot arrangements other than about a rocker shaft can be equivalently employed. For example, the input rocker and the output rocker can pivot about different axes respectively. Additionally, such axes can even be mounted on other rockers or on separate shaft seats.

[0084] Accordingly, the preferred embodiments of the invention set forth herein are for illustrative purposes only and not for purposes of limitation, so long as their variations fall within the scope of the appended claims and their equivalent claims.

Claims

1. A system for actuating at least two engine valves associated with a cylinder of an internal combustion engine, the system comprising: A first rocker arm assembly operatively connected to a first valve actuation motion source and connected to a first engine valve of the at least two engine valves, the first rocker arm assembly including a first idle member arranged in series with a first input rocker arm and a first output rocker arm, the first input rocker arm being configured to receive a first valve actuation motion from the first valve actuation motion source, and the first output rocker arm being configured to impart the first valve actuation motion to the first engine valve, wherein the first idle member is operable in a motion absorption state to prevent the first valve actuation motion from being transmitted from the first input rocker arm to the first output rocker arm, and is operable in a motion transmission state to transmit the first valve actuation motion from the first input rocker arm to the first output rocker arm; A second rocker arm assembly operatively connected to a second valve actuation motion source and connected to a second engine valve of the at least two engine valves, the second rocker arm assembly including at least one second rocker arm configured to receive a second valve actuation motion from the second valve actuation motion source and configured to impart the second valve actuation motion to the second engine valve; and A one-way coupling mechanism disposed between the first output rocker arm and the at least one second rocker arm such that the second valve actuation motion is transmitted from the at least one second rocker arm to the first output rocker arm, and the first valve actuation motion is not transmitted from the first output rocker arm to the at least one second rocker arm.

2. The system according to claim 1, wherein The first output rocker arm includes a hydraulic lash adjuster.

3. The system according to claim 1, wherein The at least one second rocker arm includes a hydraulic lash adjuster.

4. The system according to claim 1, wherein The first rocker arm assembly is configured to operate as a type II rocker arm.

5. The system according to claim 1, wherein, The first rocker arm assembly is configured to operate as a type III rocker arm.

6. The system according to claim 1, wherein, Each of the first input rocker arm and the first output rocker arm includes an axially-mounted half rocker arm.

7. The system according to claim 6, wherein, The first output rocker arm includes a lateral arm defining a central opening configured to receive the first input rocker arm therebetween.

8. The system according to claim 6, wherein, The first output rocker arm and the first input rocker arm are configured to be deployed adjacent to each other.

9. The system according to claim 1, wherein, The at least one second rocker arm includes an axially-mounted type II rocker arm.

10. The system according to claim 1, wherein The one-way coupling mechanism includes a coupling arm forming a part of the at least one second rocker arm and a coupling contact surface forming a part of the first output rocker arm, and wherein the coupling arm and the coupling contact surface are configured to contact each other.

11. The system according to claim 1, wherein, The first idle member includes a hydraulically controlled locking mechanism.

12. The system according to claim 1, wherein The first idle member includes a spring that biases the first input rocker arm toward the first valve actuation motion source and biases the first output rocker arm toward the first engine valve.

13. The system according to claim 1, wherein, The first idle member is configured to provide a fail-safe lift event.

14. The system according to claim 1, wherein, The at least one second rocker arm includes: A second floating component, the second floating component being arranged in series with a second input rocker arm and a second output rocker arm, the second input rocker arm being configured to receive the second valve actuation movement from the second valve actuation movement source, and the second output rocker arm being configured to impart the second valve actuation movement to the second engine valve, wherein the second floating component is capable of operating in a movement absorption state to prevent the second valve actuation movement from being transmitted from the second input rocker arm to the second output rocker arm, and is capable of operating in a movement transmission state to transmit the second valve actuation movement from the second input rocker arm to the second output rocker arm.

15. The system according to claim 14, wherein, The second output rocker arm includes a hydraulic lash adjuster.

16. The system according to claim 14, wherein, The second rocker arm assembly is configured to operate as a type II rocker arm.

17. The system according to claim 16, wherein, The first rocker arm assembly is configured to operate as a type II rocker arm.

18. The system according to claim 14, wherein, The second rocker arm assembly is configured to operate as a type III rocker arm.

19. The system according to claim 18, wherein, The first rocker arm assembly is configured to operate as a type III rocker arm.

20. The system according to claim 14, wherein The second input rocker arm and the second output rocker arm each include an axially-mounted half rocker arm.

21. The system according to claim 20, wherein, The second output rocker arm includes a lateral arm defining a central opening, the central opening being configured to receive the second input rocker arm therebetween.

22. The system according to claim 20, wherein The second output rocker arm and the second input rocker arm are configured to be deployed adjacent to each other.

23. The system according to claim 14, wherein, The one-way coupling mechanism includes a coupling arm forming a part of the second output rocker arm and a coupling contact surface forming a part of the first output rocker arm, and wherein the coupling arm and the coupling contact surface are configured to contact each other.

24. The system according to claim 14, wherein The second floating component includes a hydraulically controlled locking mechanism.

25. The system according to claim 14, wherein, The second floating component includes a spring that biases the second input rocker arm toward the second valve actuation movement source and biases the second output rocker arm toward the second engine valve.

26. The system according to claim 14, wherein, The second floating component is configured to provide a fail-safe lift event.

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