Rocker arm assembly of engine valve structure

Abstract

A rocker arm assembly (200) is rotatable about a rocker arm shaft (130) and includes a first portion and a second portion. The first portion is configured to receive a valve lift profile. The second portion is configured to operatively engage with one or more valves. The rocker arm assembly further includes a lost motion assembly (210) configured to absorb at least a portion of the valve lift profile; and a switchable unit (230) having an actuator assembly and a plunger (232) disposed within the plunger bore. Further, the switchable unit includes a plunger securing assembly (235).

Description

[0001] priority This application claims the benefit of U.S. Provisional Patent Application No. 63 / 501,885, filed May 12, 2023, pursuant to 35 USC § 119(e), which is incorporated herein by reference. Technical Field

[0002] This application relates to engine valve structure, and more specifically, to rocker arm assembly for promoting engine braking function in engine valve structure assembly. Background Technology

[0003] An internal combustion engine may include a valve structure, wherein, in a particular configuration, the engine valve structure may include rocker arms for controlling the opening and closing of intake valves and / or exhaust valves.

[0004] Specific implementations of the engine may include an engine braking system that, when activated, can provide early and / or additional opening of the exhaust valves. For example, the exhaust valves can be opened earlier when the piston in the cylinder is approaching the top dead center (TDC) position of its compression stroke. By opening the exhaust valves in this way through the engine braking system, compressed gas can be released through the exhaust valves via compression release. This can cause the engine to function as an energy-consuming device, thereby aiding in vehicle deceleration. Summary of the Invention

[0005] In a specific embodiment that may combine features of some or all of the above embodiments, a rocker arm assembly is disclosed, rotatable about a rocker arm axis and comprising: a first portion configured to receive a valve lift profile; and a second portion configured to operatively engage one or more of a plurality of valves based on the valve lift profile; the second portion including an actuation assembly and a switchable capsule, the actuation assembly being configured to absorb at least a portion of the valve lift profile, the switchable capsule including an actuator assembly, a plunger, and a plunger retaining assembly, the actuator assembly being switchable between a first state and a second state, the plunger being disposed within a plunger bore, the plunger being selectively extended between a retracted position and an extended position based on actuation of the actuator assembly, the plunger retaining assembly including a plunger biasing member and a retainer, the plunger biasing member being disposed between the plunger and the retainer and configured to bias the plunger toward the retracted position, wherein, corresponding to the actuator assembly being in the first state, the plunger biasing member is configured to retain the plunger in the retracted position.

[0006] In a particular embodiment that may combine some or all of the features of the above embodiments, corresponding to the actuator assembly being in a second state, the extension force of the actuator assembly overcomes the force associated with the plunger biasing member, causing the plunger to extend to the extended position. In a particular embodiment that may combine some or all of the features of the above embodiments, the plunger biasing member includes a spring.

[0007] In a particular embodiment that may combine some or all of the features of the above embodiments, the aerodynamic assembly includes: a first shaft constrained within an aerodynamic hole of the aerodynamic assembly; a second shaft disposed within the aerodynamic hole, the second shaft being longitudinally movable relative to the first shaft; and a biasing member configured to bias the second shaft away from the first shaft.

[0008] In a particular embodiment that may combine some or all of the features of the above embodiments, the second shaft of the pneumatic assembly is movable between a first position and a second position, the first position being associated with a longitudinal clearance between the first and second shafts within the pneumatic bore, and the second position being constrained by contact between the first and second shafts within the pneumatic bore. In a particular embodiment that may combine some or all of the features of the above embodiments, the actuator assembly of the switchable unit is hydraulically actuated, and wherein the plunger is selectively extended based on the hydraulic actuation of the actuator assembly.

[0009] In a particular embodiment that may combine features of some or all of the above embodiments, a first portion of the rocker arm assembly includes a roller configured to engage with a cam to receive at least a portion of the valve lift profile. In a particular embodiment that may combine features of some or all of the above embodiments, the first portion is configured to operatively engage with a pushrod to receive at least a portion of the valve lift profile.

[0010] In a particular embodiment that may combine some or all of the features of the above embodiments, a rocker arm assembly is disclosed, the rocker arm assembly being rotatable about a rocker arm axis and including: a first portion configured to receive a valve lift profile; and a second portion configured to operatively engage one or more valves based on the valve lift profile, the second portion including a pneumatic assembly including a first shaft, a second shaft, and a biasing member, the first shaft being constrained within a pneumatic orifice of the pneumatic assembly, the second shaft being disposed within the pneumatic orifice and longitudinally movable relative to the first shaft, the biasing member being configured to bias the second shaft away from the first shaft.

[0011] In a specific embodiment that can combine some or all of the features of the above embodiments, the first and second axes of the rocker arm assembly are collinearly disposed within the air hole of the air-operated assembly. In a specific embodiment that can combine some or all of the features of the above embodiments, the second axis is movable between a first position and a second position, the first position being associated with the longitudinal clearance between the first and second axes within the air hole, and the second position being constrained by the contact between the first and second axes within the air hole.

[0012] In a particular embodiment that may combine some or all of the features of the above embodiments, the pneumatic component of the rocker arm assembly is configured to operatively engage with one or more valves via a valve bridge. In a particular embodiment that may combine some or all of the features of the above embodiments, the second portion of the rocker arm assembly further includes a switchable unit with an extendable plunger, wherein the pneumatic component is configured to absorb at least a portion of the valve lift profile. In a particular embodiment that may combine some or all of the features of the above embodiments, the switchable unit further includes an actuator assembly configured to selectively extend the extendable plunger.

[0013] In a particular embodiment that may combine some or all of the features of the above embodiments, the actuator assembly of the switchable unit is hydraulically actuated, and wherein the extendable plunger can be selectively extended based on the hydraulic actuation of the actuator assembly. In a particular embodiment that may combine some or all of the features of the above embodiments, the extendable plunger is disposed within the plunger bore of the switchable unit.

[0014] In a specific embodiment that can combine some or all of the features of the above embodiments, the vent hole is parallel to the plunger hole of the switchable unit. In a specific embodiment that can combine some or all of the features of the above embodiments, the vent hole is inclined relative to the plunger hole of the switchable unit. In a specific embodiment that can combine some or all of the features of the above embodiments, the extendable plunger is configured to operatively engage with a first valve of one or more valves. In a specific embodiment that can combine some or all of the features of the above embodiments, the extendable plunger is configured to act on a pin to operatively engage with a first valve, the pin being slidably disposed within a valve bridge.

[0015] In a specific embodiment that can combine some or all of the features of the above embodiments, a valve structure system is disclosed, the valve structure system comprising: a cam having a valve lift profile; a plurality of valves, including a first valve and a second valve; a valve bridge configured to operatively engage with the plurality of valves; a rocker arm shaft; and a rocker arm assembly rotatable about the rocker arm shaft, the rocker arm assembly including a first portion and a second portion, the first portion being configured to receive the valve lift profile from the cam, and the second portion being configured to operatively engage with the plurality of valves based on the valve lift profile, the second portion including: a switchable unit. The unit, configured to operatively engage with a first valve, includes an actuator assembly and a plunger configured to selectively extend based on actuation of the actuator assembly; and an actuation assembly configured to operatively engage with a valve bridge, the actuation assembly further configured to absorb at least a portion of the valve lift profile during an engine cycle, the actuation assembly including a first shaft, a second shaft, and a biasing member, the first shaft being constrained within an actuation orifice of the actuation assembly, the second shaft being disposed within the actuation orifice and longitudinally movable relative to the first shaft, the biasing member being configured to bias the second shaft away from the first shaft. Attached Figure Description

[0016] The invention will now be described in more detail based on exemplary figures. The invention is not limited to the exemplary embodiments. Other features and advantages of various embodiments of the invention will become apparent from the following detailed description with reference to the accompanying drawings, which illustrate the following: Figure 1A and Figure 1B A schematic cross-sectional view of a rocker arm assembly corresponding to different cam rotation positions according to a specific embodiment is shown.

[0017] Figure 2 A schematic diagram of an exemplary engine valve timing diagram within an engine cycle, according to a particular embodiment, is shown.

[0018] Figure 3A A schematic partial cross-sectional view of a rocker arm assembly according to a particular embodiment is shown, and an exemplary switchable unit is further depicted in the form of enlarged illustrations.

[0019] Figure 3B A schematic partial cross-sectional view of a rocker arm assembly according to a particular embodiment is shown.

[0020] Figure 4A A schematic exploded view of a specific component of an exemplary aerodynamic assembly according to a particular embodiment is shown.

[0021] Figure 4B A schematic exploded view of a specific component of an exemplary plunger fixing assembly according to a particular embodiment is shown.

[0022] Figure 5A and Figure 5B A partially enlarged schematic cross-sectional view of an exemplary plunger fixing assembly according to a particular embodiment is shown.

[0023] Figure 6 A schematic partial cross-sectional view of a rocker arm assembly according to a particular embodiment is shown, depicting an exemplary adjustment of the aerodynamic component.

[0024] Figures 7A to 7D A schematic cross-sectional view of an aerodynamic component according to a particular embodiment is shown, depicting an exemplary adjustment process.

[0025] It should be noted that the provided drawings may be schematic rather than actual or precise; and the components and aspects in the drawings may not necessarily be to scale. Furthermore, although the same reference numerals may designate corresponding components in many cases across different views, the same components may not always be assigned the same reference numerals in each view. Detailed Implementation

[0026] Based on various embodiments of this disclosure, rocker arm assemblies and related mechanisms, apparatuses, and methods are provided herein. While this disclosure may include specific embodiments with particular features and combinations of features, as well as specific use cases, to provide a better understanding, it should be understood that this disclosure is not limited to these specific exemplary embodiments or use cases.

[0027] In a particular embodiment, the engine valve structure may include a rocker arm for controlling the opening and closing of the engine's intake and / or exhaust valves. In a particular embodiment, the rocker arm may include a reciprocating element that converts the rotational motion of a cam lobe of a rotating camshaft into motion that controls the opening and closing of the valve. In a particular embodiment, the rocker arm may be configured to rotate about a rocker arm axis, with the cam end of the rocker arm positioned in direct or indirect contact with one or more rotating cams, and the valve end located at the opposite end of the cam end, directly or indirectly (e.g., via a valve bridge) engaging with one or more valves of the engine.

[0028] Refer to the attached diagram. Figure 1A and Figure 1B A schematic cross-sectional view of a rocker arm assembly corresponding to different cam rotation positions according to a particular embodiment is shown. In a particular embodiment, the valve structure assembly 100 may include a rocker arm assembly 200 having a first portion 110 configured to receive a valve lift profile. In a particular embodiment, the first portion 110 may correspond to a cam end configured to receive a valve lift profile from a suitable component, such as a cam. By way of example and not limitation, the first portion 110 may be configured to receive a valve lift profile from a cam 120 via a roller mechanism 125, such as... Figure 1A and Figure 1BAs shown in the figure. By way of example and not limitation, the first part 110 can be configured to receive a valve lift profile via the push rod mechanism 170, such as Figure 6 As shown in the figure. In a particular embodiment, the rocker arm assembly 200 may be configured to rotate about the rocker arm axis 130.

[0029] In a particular embodiment, the rocker arm assembly 200 may include a second portion 140 configured to operatively engage one or more valves of a plurality of valves of the valve structure assembly 100 based on a valve lift profile received by the rocker arm assembly 200. In a particular embodiment, the second portion 140 may be configured to operatively engage with two valves, such as a first valve 160 and a second valve 165. In a particular embodiment, the rocker arm assembly 200 may include an actuation assembly 210. By way of example, and not limitation, the actuation assembly 210 may be configured to act directly or indirectly on one or more valves associated with the valve structure assembly 100. By way of example, and not limitation (such as in...) Figure 1A and Figure 1B As shown in the figure, the pneumatic assembly 210 can be configured to act on both valves 160 and 165 (e.g., via valve bridge 145). In a particular embodiment, the pneumatic assembly 210 can be configured to act at a common engagement location of valve bridge 145 (e.g., the central portion of valve bridge 145).

[0030] In a particular embodiment, the rocker arm assembly 200 may include a switchable unit 230. In a particular embodiment, the switchable unit 230 may be configured to act directly or indirectly on one or more valves associated with the valve structure assembly 100. This is done by way of example, not limitation (such as in...). Figure 1A and Figure 1B As shown in the figure, the switchable unit 230 can be configured to act on one of a plurality of valves, such as the first valve 160. In a particular embodiment, the switchable unit 230 can access and / or engage the first valve 160 via a suitable mechanism provided in the valve bridge 145, such as a sliding pin 150 or a bridging mechanism (not shown).

[0031] It should be understood that, although the implementation of the rocker arm assembly 200 (such as in...) Figure 1A and Figure 1B The rocker arm assembly 200 shown herein may include both the pneumatic component 210 and the switchable unit 230, and specific features and aspects may be described in a particular combination to provide understanding, but implementations of the rocker arm assembly 200 having other combinations, such as one or the other of the pneumatic component 210 and the switchable unit 230, are possible and fully contemplated in this disclosure.

[0032] In a particular embodiment, the rocker arm assembly 200 may be configured to allow switching of engine braking functions. In a particular embodiment, the rocker arm assembly 200 may be configured as an integrated engine braking rocker arm. In a particular embodiment, the rocker arm assembly 200 may be configured to engage with a plurality of exhaust valves. By way of example, and not limitation, a first valve 160 may correspond to an engine braking exhaust valve, and a second valve 165 may correspond to a main exhaust valve.

[0033] In a particular embodiment, based on the received valve profile, the aerodynamic assembly 210 and / or the switchable unit 230 can be used to selectively add, subtract, and / or engage one or both of the first valve 160 and the second valve 165. In a particular embodiment, the rocker arm assembly 200 can be configured to receive a valve lift profile including a composite valve profile from the cam 120. By way of example, and not limitation, the composite valve profile can include a combination of valve lifts intended to operate a particular one or both of the first valve 160 and the second valve 165. In a particular embodiment, the composite valve profile can include a normal or main exhaust valve profile and an engine brake valve profile.

[0034] By way of example, and not limitation, such as in an exemplary integrated engine brake rocker arm, rocker arm assembly 200 may receive a valve lift profile from cam 120, the valve lift profile including a main lift segment 122; modified approach and descent segments (i.e., upper and lower ramps) of the main lift segment 122 based on engine braking requirements; and / or one or more separate engine brake lift segments 124. By way of example, and not limitation, Figure 1B A cam 120 is shown, having an exemplary main lift segment 122 and an engine brake lift segment 124 relative to a base circle 123. This is by way of example, not limitation. Figure 1B It also includes a modified gradient relative to the non-engine brake exhaust profile (not shown) leading to and leaving the main lift section 122.

[0035] In a particular embodiment, the rocker arm assembly 200 may be configured such that the aerodynamic assembly 210 can absorb the portion of the compound valve lift profile corresponding to engine braking operation and only transmit the portion of the compound valve lift profile required for normal exhaust valve operation (i.e., non-engine braking operation, also known as driving mode). In a particular embodiment, the aerodynamic assembly 210 may be configured to act on the valve bridge 145 to operate both the first valve 160 and the second valve 165. Accordingly, in a particular embodiment, the aerodynamic assembly 210 may be configured to receive the compound valve lift profile, absorb the portion of the profile corresponding to engine braking, and apply the valve lift profile corresponding to normal exhaust valve operation to both exhaust valves.

[0036] In a particular implementation, the switchable unit 230 may be configured to switch between a first state and a second state. By way of example, and not limitation, the switchable unit 230 may be powered and / or turned on in the first state. By way of example, and not limitation, the switchable unit 230 may be disabled and / or turned off in the second state.

[0037] In certain embodiments, the switchable unit 230 may be configured to selectively act on a designated engine brake valve among a plurality of exhaust valves. In a particular embodiment associated with a rocker arm assembly 200 configured for engine braking, the switchable unit 230 in a first state may correspond to engaging an engine braking mode. By way of example, and not limitation, in the first state, the switchable unit 230 may be configured to engage with a first valve 160 to transmit and / or provide engine brake lift to the first valve 160. In a particular embodiment, the switchable unit 230 may engage with the first valve 160 via a sliding pin 150 passing through the valve bridge 145, or engage with the first valve using another suitable platform or mechanism.

[0038] In a particular embodiment, the switchable unit 230 in the second state may correspond to disengaging from the engine braking mode and thereby switching to normal operation or mode, also known as driving mode. By way of example, and not limitation, in the second state, the switchable unit 230 may be configured to retract and / or disengage the supply of engine braking lift to the first valve 160.

[0039] Figure 2 A schematic diagram of an engine valve timing diagram 300 within an engine cycle, depicted by way of non-limiting example and according to a particular embodiment, is shown. By way of example and not limitation, the diagram is characterized based on a four-stroke intake-compression-power-exhaust cycle, with the piston top dead center (TDC) and bottom dead center (BDC) events marked accordingly. In a particular embodiment, in driving mode (i.e., when the engine is disengaged from braking), both the first valve 160 and the second valve 165 can operate corresponding to a common exhaust valve profile (such as the main exhaust valve profile 310). In a particular embodiment (such as for a particular integrated engine brake rocker arm embodiment), in driving mode, the switchable unit 230 can be retracted and / or disengaged; the rocker arm assembly 200 can receive a compound valve lift profile; the aerodynamic assembly 210 can absorb the portion of the compound profile corresponding to the engine braking lift, and the resulting main exhaust valve profile 310 can be transferred to both the first valve 160 and the second valve 165 (such as via valve bridge 145). By way of example rather than limitation, the main exhaust lift 340 can correspond to the main lift segment 122 of the cam 120.

[0040] In certain implementations (such as for a particular integrated engine brake rocker arm implementation), in engine braking mode, the switchable unit 230 can extend and / or engage; the rocker arm assembly 200 can receive a compound valve lift profile; the aerodynamic assembly 210 can continuously absorb the portion of the compound profile corresponding to the engine braking lift and can transfer the resulting main exhaust valve profile 310 to both the first valve 160 and the second valve 165 (e.g., via valve bridge 145). By way of example, and not limitation, the main exhaust lift 340 can correspond to the main lift segment 122 of the cam 120. Accordingly, in a particular implementation, the second valve 165 can operate continuously during engine braking as it does in driving mode. Individually and / or additionally, in a particular implementation, the second valve 165 can be engaged via the switchable unit 230 to effectively receive engine brake valve profiles, such as engine brake valve profile 320. In a particular implementation, the engine brake valve profile 320 can include one or more independent valve lift events, such as brake gas recirculation lift 350 (in Figure 2 (Also known as BGR). By way of example, and not limitation, the brake gas recirculation event can fill the engine cylinder with additional mass and can occur when the pressure difference between the exhaust manifold and the cylinder pressure is at its maximum. By way of example, and not limitation, the brake gas recirculation lift 350 can correspond to the independent engine brake lift segment 124.

[0041] By way of example rather than limitation, the engine brake valve profile 320 may include one or more continuous, tilted, and / or offset valve lifts, such as compression release 360 ​​(in... Figure 2 (also referred to as CR in English). By way of example, and not limitation, in some embodiments, compression release can generate primary engine braking power, and opening timing can determine decompression pressure. In certain embodiments, portions of the engine brake valve profile 320 may be modified, intersect with, or otherwise associated with portions of the resulting exhaust valve profile 310.

[0042] Figure 3A A schematic partial cross-sectional view of a rocker arm assembly according to a particular embodiment is shown, with an exemplary switchable unit further depicted by enlarging the illustration. Figure 3B A schematic partial cross-sectional view of a rocker arm assembly according to a particular embodiment is shown.

[0043] As previously discussed, although the rocker arm assembly 200 includes the pneumatic assembly 210 and the switchable unit 230 for illustrative and understanding purposes in the depicted embodiments, they do not need to be present together in every embodiment; every suitable aspect and feature of each of the pneumatic assembly 210 and / or the switchable unit 230 (both individually and in combination) is contemplated herein.

[0044] In a particular embodiment, the pneumatic assembly 210 may include a first shaft 214 and a second shaft 218 disposed within a pneumatic bore 215 of the pneumatic assembly 210. In a particular embodiment, the first shaft 214 may include a clearance screw. In a particular embodiment, the first shaft 214 may be coupled to a nut 212. In a particular embodiment, the pneumatic assembly 210 may be provided with a biasing member 216. By way of example, and not limitation, the biasing member 216 may include a spring. By way of example, and not limitation, the biasing member 216 may be used to absorb at least a portion of the valve lift profile received by the rocker arm assembly 200. In a particular embodiment, the second shaft 218 may include a valve end configured to engage directly or indirectly with one or more valves. In a particular embodiment, the valve end of the second shaft 218 may be configured to engage with a valve bridge (such as valve bridge 145). In a particular embodiment, the valve end of the second shaft 218 may include suitable engagement portions, such as a plunger end, a plunger pad, and / or an E-shaped foot (e.g., an E-shaped foot 220).

[0045] In a specific embodiment of the aerodynamic component 210 (such as in Figure 3A In the example depicted (as a non-limiting illustrative example), the first shaft 214 and the second shaft 218 of the aerodynamic assembly 210 may be longitudinally constrained relative to each other, allowing them to translate back and forth together relative to the bore housing 222. In a particular embodiment, a biasing member 216 may be disposed proximal to and / or coaxial with the first shaft 214. In a particular embodiment, the biasing member 216 may be configured to act on a collar 219 of the second shaft 218.

[0046] In certain embodiments, the uppermost and / or fully retracted position of the aerodynamic assembly 210 can be positioned or constrained by the collar 219 contacting a suitable flange or surface (such as that provided on the bore housing 222). By way of example, and not limitation, after proper adjustment and / or calibration, the E-foot 220, the second shaft 218, the first shaft 214, and the nut 212 can translate relative to the bore housing 222 during operation without relative longitudinal displacement between them. By way of example, and not limitation, the E-foot 220, the second shaft 218, the first shaft 214, and the nut 212 can move as a composite unit relative to the bore housing 222 for longitudinal movement, thereby rising and falling between the retracted and extended positions based on the balance between the force received through the E-foot 220 and the force due to the biasing member 216 biasing towards the extended position.

[0047] Figure 4A A schematic exploded view of specific components of an exemplary aerodynamic assembly according to a particular embodiment is shown. In a particular embodiment of the aerodynamic assembly 210 (such as in...), Figure 3B In the embodiment depicted (as a non-limiting illustrative example), the second shaft 218 and the first shaft 214 may be disposed within the air passage 215 such that the second shaft 218 is longitudinally movable relative to the first shaft 214. By way of example, and not limitation, while the first shaft 214 may be optionally adjustable, such as for calibration, maintenance, and / or other adjustments (e.g., clearance), in a particular embodiment, the first shaft 214 may be constrained to a longitudinal position within the air passage 215 during normal operation of the valve assembly 100. In a particular embodiment, the first shaft 214 and the second shaft 218 may be disposed collinearly within the air passage 215.

[0048] In a particular embodiment, the second shaft 218 can be supported and / or prevented from being disassembled by suitable attachments (such as snap-fit ​​217) while allowing free longitudinal translation within the plenum 215. In a particular embodiment, the biasing member 216 can be configured to separate the first shaft 214 and the second shaft 218 in the longitudinal direction, i.e., increasing the relative clearance 224 between the first shaft 214 and the second shaft 218. In a particular embodiment, the uppermost and / or fully retracted position of the second shaft 218 can be constrained by contact with the first shaft 214 fixed within the plenum 215. In a particular embodiment, the relative clearance 224 can be zero, corresponding to the second shaft 218 being in the uppermost and / or fully retracted position within the plenum 215.

[0049] In a particular embodiment, the aerodynamic assembly 210 may include an inlet / outlet 290. By way of example, and not limitation, the inlet / outlet 290 may be positioned to provide entry and exit for purposes such as calibrating and / or otherwise adjusting the relative clearance 224 between the first shaft 214 and the second shaft 218 using a calibration shim 292. By way of non-limiting example, Figure 6 The diagram shows a calibration shim 292 configured to pass through inlet / outlet 290 to determine a relative clearance 224. By way of example, and not limitation, the relative clearance 224 can be calibrated and / or otherwise adjusted to provide clearance adjustment to the aerodynamic assembly 210. By way of example, and not limitation, the relative clearance 224 can be calibrated or otherwise adjusted to determine and / or fix the maximum travel of the second shaft 218, i.e., the lowermost and / or fully extended position of the second shaft 218. In a particular embodiment, the desired relative clearance 224 can be calibrated, adjusted, and / or otherwise fixed, such as by means of a nut 212 within the aerodynamic bore 215.

[0050] In a particular embodiment, the switchable unit 230 may include a suitable actuator assembly configured to selectively extend and retract a plunger, such as plunger 232. While specific actuator assemblies may be described in more detail herein as a non-limiting illustration, this disclosure fully contemplates any suitable actuator assembly for performing the functions disclosed herein. In a particular embodiment, the switchable unit 230 may include an electromagnetic actuator assembly configured (e.g., using a solenoid) to selectively extend and retract a plunger, such as plunger 232. In a particular embodiment, the switchable unit 230 may include a hydraulic actuator assembly, such as, in a non-limiting example, at least Figure 3A , Figure 3B and Figure 6 As shown in the image.

[0051] In a specific implementation method (such as at least) Figure 3A , Figure 3B and Figure 6 As shown in the diagram, the switchable unit 230 (equipped with any suitable actuator assembly) may include a selectively extendable plunger 232. In a particular embodiment, the plunger 232 may extend between a retracted position (away from the valve engagement) and an extended position (towards the valve engagement) based on actuation of the actuator assembly.

[0052] In a particular embodiment, in the extended position, the plunger 232 may be configured to be substantially rigid, i.e., to support and resist forces received due to contact with the corresponding valve engagement. By way of example, and not limitation, the plunger 232 in the extended position may be configured to contact the sliding pin 150 to transmit at least a portion of the received valve lift profile to the first valve 160, the extended position potentially corresponding to an actuator assembly configuration that is powered or activated and an engine braking mode.

[0053] In a particular embodiment, in the retracted position, plunger 232 may be configured to be substantially collapsed, soft, and / or compliant, i.e., unable to support and / or resist forces arising from contact with the corresponding valve engagement. By way of example, and not limitation, plunger 232 in the retracted position may be configured to collapse upon any accidental contact with sliding pin 150, which may correspond to a disabled or closed actuator assembly configuration and a normal or driving mode (engine brake off).

[0054] In a particular implementation method (such as in Figure 3A (Illustration) and Figure 6 As shown in the diagram, the contact between the plunger 232 and the corresponding valve engagement (such as the sliding pin 150) can exert significant forces, loads, shocks, pulses, and / or wear on the switchable unit 230. This is by way of example, not limitation. Figure 3A The enlarged illustration shows a specific surface (marked by a dashed ellipse) that can receive significant wear due to such contact. However, such contact is required when the plunger 232 extends under the action of the actuator assembly. In certain embodiments, incidental contact between the plunger 232 and the corresponding valve engagement occurs when the plunger 232 is in a retracted or soft position because such embodiments may lack an active means for adequately constraining, supporting, and / or holding the plunger 232 in the retracted position when the plunger 232 is in a collapsed or soft position.

[0055] In a particular implementation method (such as in Figure 3B As shown in the diagram, the switchable unit 230 may include a plunger retaining assembly 235 for constraining, supporting, and / or holding the plunger 232 in a retracted position when the plunger 232 collapses or softens. In a particular embodiment, the plunger retaining assembly 235 may be configured to release and / or allow the plunger 232 to extend due to the switchable unit 230 based on the extension force applied by the actuator assembly when it is powered or activated to extend the plunger 232.

[0056] Figure 4BA schematic exploded view of specific components of an exemplary plunger retaining assembly according to a particular embodiment is shown. In a particular embodiment, the plunger retaining assembly 235 may include a plunger biasing member 238 and a retainer 236. In a particular embodiment, the plunger biasing member 238 may be disposed between the plunger 232 and the retainer 236.

[0057] In a particular embodiment, the venting hole 215 may be configured to be parallel to the plunger hole and / or plunger translation axis of the switchable unit 230.

[0058] Figure 5A and Figure 5B A partially enlarged schematic cross-sectional view of an exemplary plunger retaining assembly according to a particular embodiment is shown. In a particular embodiment, the plunger biasing member 238 may be configured to bias the plunger 232 toward a retracted position of the plunger 232. In a particular embodiment, the retainer 236 may include annular and / or ring-shaped structures that may be configured to attach to retain the plunger biasing member 238 in place. In a particular embodiment (such as in...) Figure 5A As shown in the diagram, the plunger biasing member 238 can be suitably calibrated to retract and / or fix the plunger 232 to its retracted position when the actuator assembly is disabled or closed. In a particular embodiment, the plunger biasing member 238 can be suitably calibrated additionally or separately to release, facilitate, and / or allow the extension of the plunger 232 when the actuator assembly is powered or turned on. By way of example, and not limitation, corresponding to the powered or turned-on state of the actuator assembly, the extension force of the actuator assembly can overcome the force associated with the plunger biasing member 238, allowing the plunger 232 to extend to an extended position, such as engaging a valve engagement. In a particular embodiment, the plunger biasing member 238 may include a spring.

[0059] It should be understood that while the plunger retaining assembly 235 may be shown in combination with a particular type of actuator assembly and / or switchable unit 230 as a non-limiting example herein, the features and functions of the plunger retaining assembly 235 disclosed herein are fully contemplated in the context of retaining any suitable type of plunger and / or for any suitable application, which is not limited to a particular type of unit, or engine valve structure, and / or engine braking application.

[0060] Figure 6 A schematic partial cross-sectional view of a rocker arm assembly according to a particular embodiment is shown, depicting an exemplary adjustment of the air-lift component. This is by way of example, not limitation. Figure 6The clearance adjustment and / or calibration process according to a specific embodiment of the aerodynamic assembly can be described. As previously discussed, in a specific embodiment of the aerodynamic assembly 210, the inlet / outlet 290 can provide convenient and rapid access to calibrate and / or otherwise adjust the maximum extension of the second shaft 218 by adjusting the relative clearance 224. By way of example, and not limitation, a suitably sized calibration shim 292 can be inserted via the inlet / outlet 290, and the first shaft 214 can be temporarily translated by loosening and tightening the nut 212, so that the relative clearance 224 between the first shaft 214 and the second shaft 218 is properly fixed.

[0061] Alone or in addition, compared to the design of the pneumatic assembly 210 in which the first shaft 214 rises based on the contact of the e-shaped foot 220 with the valve engagement (such as the valve bridge 145), a particular embodiment of the pneumatic assembly 210 having a longitudinally fixed first shaft 214 can provide the packaged benefits of installation and design freedom within the vertically confined space of the engine cylinder head.

[0062] In a specific implementation method (such as at least) Figure 3A and Figure 6 As shown in the diagram, the actuator assembly of the switchable unit 230 can be hydraulically actuated, including a hydraulic actuator assembly 240. In a particular embodiment, the hydraulic actuator assembly 240 can be fluidly connected to a controllable high-pressure hydraulic fluid line, such as through a hydraulic supply port 260. By way of example, and not limitation, the hydraulic supply port 260 can be connected to an engine hydraulic supply passage 262 passing through the rocker arm shaft 130 and controlled by an oil control valve (not shown) to open (allow) or close (deny) the supply of pressurized hydraulic fluid to the hydraulic actuator assembly 240 via the hydraulic supply port 260.

[0063] In a particular embodiment, the hydraulic actuator assembly 240 may include an upper chamber 242 connected to a hydraulic supply port 260 and a lower chamber 244 controllably separable from the upper chamber 242 via a check valve 246. In a particular embodiment, the lower chamber 244 may be configured to act on and extend the plunger 232 when the lower chamber 244 is filled with pressurized hydraulic fluid.

[0064] In a particular embodiment, check valve 246 may include a ball 248 or other suitable valve member. By way of example, and not limitation, the ball 248 may be biased against a flow passage of check valve 246 such that the ball 248 can be used to close the flow passage unless the ball 248 is subjected to an external force. In a particular embodiment, a control pin 250 may be provided, which is biased toward the ball 248 by a control pin biasing member 252. In a particular embodiment, the control pin biasing member 252 may include a spring.

[0065] In a particular embodiment, during operation when the switchable unit 230 is in a disabled or closed state, the pressurized hydraulic fluid supply to the hydraulic actuator assembly 240 is cut off based on the oil control valve for shutting off the engine, thereby cutting off the pressurized hydraulic fluid supply to the hydraulic actuator assembly 240 via the hydraulic supply port 260. In a particular embodiment, correspondingly, the control pin 250 can push back the ball 248 to allow residual hydraulic fluid to flow freely through the flow passage of the check valve 246. By way of example, and not limitation, since both chambers (lower chamber 244 and upper chamber 242) may contain residual and / or relatively low-pressure fluid in this state, the plunger 232 may collapse and / or be unable to resist or exert force on the valve engagement (such as the sliding pin 150). By way of example rather than limitation, based on the control pin 250, the ball 248 is kept open. The ball 248 can be switchably presented as not operating as a hydraulic check valve mechanism, such as selectively opening and closing the fluid flow passage of the check valve 246 in response to the effective force and / or pressure acting on the ball 248.

[0066] In a particular embodiment, during operation when the switchable unit 230 is powered or in an on state, a pressurized hydraulic fluid supply to the hydraulic actuator assembly 240 can be initiated by opening the engine's oil control valve, thereby connecting the hydraulic actuator assembly 240 to the pressurized hydraulic fluid supply via the hydraulic supply port 260, and thereby pressurizing the hydraulic fluid in the upper chamber 242. Accordingly, in a particular embodiment, the control pin 250 can be pushed against the force of the control pin biasing member 252 (such as based on the pressure of the pressurized hydraulic fluid in the upper chamber 242), thereby disengaging or retracting the contact between the control pin 250 and the ball 248.

[0067] In a particular embodiment, correspondingly, in a state where the control pin 250 can be withdrawn from contact with the ball 248 by a specific means of activating the switchable unit 230, the effective differential force acting on the ball 248 can allow and / or facilitate the ball 248 to selectively open and close the fluid flow passage of the check valve 246. By way of example, and not limitation, in a state where the control pin 250 can be withdrawn from contact with the ball 248, the ball 248 can be configured to open the fluid flow passage of the check valve 246 based on the hydraulic fluid pressure in the upper chamber 242 (and / or other forces acting on the ball 248 to open the fluid flow passage of the check valve 246) exceeding the effective hydraulic fluid pressure in the lower chamber 244 (and / or other forces acting on the ball 248 to close the fluid flow passage of the check valve 246). By way of example rather than limitation, in which the control pin 250 can be retracted from the ball 248, the ball 248 can be configured to close the fluid flow passage of the check valve 246 based on the hydraulic fluid pressure in the upper chamber 242 (and / or other forces acting on the ball 248 to open the fluid flow passage of the check valve 246) being lower than the effective hydraulic fluid pressure in the lower chamber 244 (and / or other forces acting on the ball 248 to close the fluid flow passage of the check valve 246).

[0068] In a particular embodiment, the lower chamber 244 may accordingly include hydraulic fluid at an effective pressure at least equal to the effective pressure in the upper chamber 242, to keep the ball 248 closed against the fluid flow passage of the check valve 246, such as holding the plunger 232 in an extended position. In a particular embodiment, based on the balance of the effective differential forces acting on the ball 248, the fluid flow passage of the check valve 246 may be opened as needed to pressurize the lower chamber 244 and / or allow additional hydraulic fluid into the lower chamber 244, such as to extend and / or hold the extended plunger 232, and subsequently close. In a particular embodiment, one or more additional or alternative forces (such as due to suitable biasing members) may contribute to acting on one or more effective hydraulic pressures that operatively determine the open or closed state of the ball 248. In a particular embodiment, when the plunger 232 receives force from the valve engagement (such as the sliding pin 150), the corresponding increase in the effective hydraulic fluid pressure in the lower chamber 244 relative to the upper chamber 242 can serve to keep the ball 248 closed, thereby sealing the lower chamber 244, trapping the hydraulic fluid therein, and thus allowing the plunger 232 to remain rigidly extended to resist and apply forces relative to the valve engagement (such as the sliding pin 150).

[0069] Figure 6 A non-limiting example of a rocker arm assembly 200 configured to receive a valve profile from a push rod mechanism 170 is also shown.

[0070] Figures 7A to 7D A schematic cross-sectional view of an aerodynamic component according to a particular embodiment is shown, depicting an exemplary adjustment process. This is by way of example, not limitation. Figures 7A to 7D The clearance adjustment and / or calibration process according to a specific implementation of the aerodynamic component can be described. In a particular implementation, features as disclosed herein can significantly simplify and accelerate the maintenance, calibration, and / or adjustment processes of the aerodynamic component 210, such as clearance setting. By way of example and not limitation, such as Figure 7A As shown, nut 212 can be rotated to release the air-operated assembly 210. This is by way of example, not limitation. Figure 7B As shown, the first axis 214 can then be rotated upwards to increase the relative clearance 224 between the first axis 214 and the second axis 218. This is by way of example, not limitation, as... Figure 7C As shown, a suitable calibration shim 292 (such as including a calibration slide gauge) can be inserted via inlet / outlet 290, and the first shaft 214 can be tightened until it contacts the hard stop corresponding to the calibration shim 292. This is by way of example, not limitation, as... Figure 7D As shown, nut 212 can then be tightened to complete the gap adjustment and setting of switchable unit 230.

[0071] other The foregoing description of the embodiments is provided for illustrative and descriptive purposes. It is not intended to be exhaustive or limiting of this disclosure. Individual elements or features in a particular embodiment are generally not limited to that particular embodiment, but where applicable, these elements or features are interchangeable and can be used in the chosen embodiment, even if not specifically shown or described. This content can also be varied in many ways. Such variations should not be considered as departing from this disclosure, and all such variations are intended to be included within the scope of this disclosure.

[0072] While the invention has been shown and described in detail in the accompanying drawings and the foregoing description, such showing and description should be considered illustrative or exemplary rather than restrictive. It should be understood that changes and modifications can be made by those skilled in the art within the scope of the following claims. Specifically, the invention covers other embodiments with any combination of features from the different embodiments described above and below. Furthermore, statements characterizing the invention herein refer to embodiments of the invention, and not necessarily all embodiments.

[0073] The terms used in the claims should be interpreted as having the broadest reasonable meaning consistent with the foregoing description. For example, the use of the articles “a” or “the” when introducing an element should not be interpreted as excluding multiple elements. Similarly, the expression “or” should be interpreted as inclusive, such that the expression “A or B” does not exclude “A and B” unless it is clear from the context or the foregoing description that it refers only to one of A and B. Furthermore, the expression “at least one of A, B, and C” should be interpreted as one or more of the group of elements consisting of A, B, and C, and should not be interpreted as requiring at least one of each of the listed elements A, B, and C, regardless of whether A, B, and C are related as a category or otherwise. In addition, the expressions “A, B, and / or C” or “at least one of A, B, or C” should be interpreted as including any single entity of the listed elements (e.g., A), any subset of the listed elements (e.g., A and B), or the complete list of elements (A, B, and C).

[0074] The numerical ranges stated in this application should be interpreted as including the endpoints of the stated ranges. Specific axes (such as one or more transverse and / or longitudinal axes) that may be omitted in some illustrations herein should be interpreted as existing in every illustration or situation associated with or referring to therein.

Claims

1. A rocker arm assembly rotatable about a rocker shaft and comprising: a first portion configured to receive a valve lift profile; and a second portion configured to operatively engage with one or more valves based on the valve lift profile, the second portion comprising: a lost motion assembly configured to absorb at least a portion of the valve lift profile; and a switchable unit comprising: an actuator assembly switchable between a first state and a second state; a plunger disposed within a plunger bore, the plunger selectively extendable between a retracted position and an extended position based on actuation of the actuator assembly; and a plunger securing assembly comprising a plunger biasing member and a retainer, the plunger biasing member disposed between the plunger and the retainer and configured to bias the plunger toward the retracted position, wherein corresponding to the actuator assembly being in the first state, the plunger biasing member is configured to secure the plunger at the retracted position.

2. The rocker arm assembly of claim 1, wherein, corresponding to the actuator assembly being in the second state, an extension force of the actuator assembly overcomes a force associated with the plunger biasing member such that the plunger extends to the extended position.

3. The rocker arm assembly of claim 1, wherein, the plunger biasing member comprises a spring.

4. The rocker arm assembly of claim 1, wherein, the lost motion assembly comprises: a first shaft constrained within a lost motion bore of the lost motion assembly; a second shaft disposed within the lost motion bore, the second shaft longitudinally movable relative to the first shaft; and a biasing member configured to bias the second shaft away from the first shaft.

5. The rocker arm assembly of claim 4, wherein, the second shaft is movable between a first position associated with a longitudinal gap between the first shaft and the second shaft within the lost motion bore and a second position constrained by contact between the first shaft and the second shaft within the lost motion bore.

6. The rocker arm assembly of claim 1, wherein, the actuator assembly of the switchable unit is hydraulically actuated, and wherein the plunger is selectively extendable based on the hydraulic actuation of the actuator assembly.

7. The rocker arm assembly of claim 1, wherein, the first portion comprises a roller configured to engage with a cam to receive at least a portion of the valve lift profile.

8. The rocker arm assembly of claim 1, wherein, the first portion is configured to operatively engage with a push rod to receive at least a portion of the valve lift profile.

9. A rocker arm assembly rotatable about a rocker shaft and comprising: a first portion configured to receive a valve lift profile; and a second portion configured to operatively engage with one or more valves based on the valve lift profile, the second portion comprising a lost motion assembly comprising: a first shaft constrained within a lost motion bore of the lost motion assembly; a second shaft disposed within the lost motion bore, the second shaft longitudinally movable relative to the first shaft; and a biasing member configured to bias the second shaft away from the first shaft.

10. The rocker arm assembly of claim 9, wherein, the first shaft and the second shaft are disposed collinearly within the lost motion bore of the lost motion assembly.

11. The rocker arm assembly of claim 9, wherein, the second shaft is movable between a first position associated with a longitudinal gap between the first shaft and the second shaft within the lost motion bore and a second position constrained by contact between the first shaft and the second shaft within the lost motion bore.

12. The rocker arm assembly of claim 9, wherein, The lost motion assembly is configured to operatively engage with one or more valves via a valve bridge.

13. The rocker arm assembly of claim 9, wherein, The second portion further includes a switchable unit having an extendable plunger, and wherein the lost motion assembly is configured to absorb at least a portion of the valve lift profile.

14. The rocker arm assembly of claim 13, wherein, The switchable unit further includes an actuator assembly configured to selectively extend the extendable plunger.

15. The rocker arm assembly of claim 14, wherein, The actuator assembly of the switchable unit is hydraulically actuated, and wherein the extendable plunger is selectively extendable based on the hydraulic actuation of the actuator assembly.

16. The rocker arm assembly of claim 13, wherein, The extendable plunger is disposed within a plunger bore of the switchable unit.

17. The rocker arm assembly of claim 16, wherein, The lost motion bore is parallel to the plunger bore of the switchable unit.

18. The rocker arm assembly of claim 13, wherein, The extendable plunger is configured to operatively engage with a first valve of the one or more valves.

19. The rocker arm assembly of claim 18, wherein, The extendable plunger is configured to act on a pin to operatively engage with the first valve, the pin being slidably disposed within a valve bridge.

20. A valve train system, comprising: a cam provided with a valve lift profile; a plurality of valves including a first valve and a second valve; a valve bridge configured to operatively engage with the plurality of valves; a rocker shaft; and a rocker assembly rotatable about the rocker shaft, the rocker assembly including: a first portion configured to receive the valve lift profile of the cam; and a second portion configured to operatively engage with the plurality of valves based on the valve lift profile, the second portion including: a switchable unit configured to operatively engage with the first valve, the unit including an actuator assembly and a plunger, the plunger configured to be selectively extendable based on actuation of the actuator assembly; and a lost motion assembly configured to operatively engage with the valve bridge, the lost motion assembly further configured to absorb at least a portion of the valve lift profile during an engine cycle, the lost motion assembly including: a first shaft constrained within a lost motion bore of the lost motion assembly; a second shaft disposed within the lost motion bore, the second shaft being longitudinally movable relative to the first shaft; and a biasing member configured to bias the second shaft away from the first shaft.

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