Rocker arm assembly and valve mechanism system

Abstract

The utility model relates to a rocker arm assembly and a valve mechanism system. The rocker arm assembly is rotatable about a rocker arm shaft 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 operably engage with one or more valves. The rocker arm assembly also includes a freewheeling assembly configured to absorb at least a portion of the valve lift profile, and a switchable capsule having an actuator assembly and a plunger disposed within a plunger bore.

Description

[0001] priority

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 501,885, filed on May 12, 2023, under 35 U.S.C. §119(e), which is incorporated herein by reference. Technical Field

[0003] The present application relates to engine valve trains and, more particularly, to rocker arm assemblies used in engine valve train assemblies to facilitate engine braking functions. Background Art

[0004] An internal combustion engine may include a valvetrain, wherein in certain configurations, the engine valvetrain may include rocker arms for controlling the opening and closing of intake valves and / or exhaust valves.

[0005] Certain embodiments of the engine may include an engine braking system that may provide for advance and / or additional opening of the exhaust valve at start-up. For example, the exhaust valve may be opened additionally early when the piston in the cylinder may be near the top dead center (TDC) position of its compression stroke. Through such opening of the exhaust valve by the engine braking system, compressed gas may be released through compression release of the exhaust valve. This may cause the engine to act as a power consuming device, which may help to slow the vehicle. Summary of the invention

[0006] In a specific embodiment that may combine features of some or all of the above embodiments, a rocker arm assembly is disclosed that is rotatable about a rocker arm shaft and includes: a first portion configured to receive a valve lift profile; and a second portion configured to operably engage with one or more valves of a plurality of valves based on the valve lift profile, the second portion including: an idle motion assembly configured to absorb at least a portion of the valve lift profile; and a switchable diaphragm cartridge including: an actuating member configured to actuate a valve lift profile; and a switchable diaphragm cartridge configured to actuate a valve lift profile. An actuator assembly capable of switching between a first state and a second state; a plunger disposed in a plunger hole, the plunger being selectively extendable and retractable between a retracted position and an extended position based on actuation of the actuator assembly; and a plunger fixing assembly comprising a plunger biasing member and a retainer, the plunger biasing member being disposed between the plunger and the retainer and being configured to bias the plunger toward the retracted position, wherein corresponding to the first state of the actuator assembly, the plunger biasing member is configured to fix the plunger at the retracted position.

[0007] In a specific embodiment that may combine the features of some or all of the above embodiments, corresponding to the second state of the actuator assembly, the extension force of the actuator assembly overcomes the force associated with the plunger biasing member so that the plunger is extended to the extended position. In a specific embodiment that may combine the features of some or all of the above embodiments, the plunger biasing member comprises a spring.

[0008] In a specific embodiment that can combine the features of some or all of the above-mentioned embodiments, the idler assembly includes: a first shaft, which is confined in an idler hole of the idler assembly; a second shaft, which is disposed in the idler hole and is capable of longitudinal movement relative to the first shaft; and a biasing member, which is configured to bias the second shaft away from the first shaft.

[0009] In a specific embodiment that can combine the features of some or all of the above embodiments, the second shaft of the idler assembly can move between a first position and a second position, the first position being associated with a longitudinal gap in the idler hole between the first shaft and the second shaft, and the second position being limited by contact in the idler hole between the first shaft and the second shaft. In a specific embodiment that can combine the features of some or all of the above embodiments, the actuator assembly of the switchable diaphragm is hydraulically actuated, and wherein the plunger can be selectively retracted and retracted based on the hydraulic actuation of the actuator assembly.

[0010] In a specific embodiment that may combine the features of some or all of the above embodiments, the first portion of the rocker arm assembly comprises a roller configured to engage with a cam to receive at least a portion of the valve lift profile. In a specific embodiment that may combine the features of some or all of the above embodiments, the first portion is configured to operably engage with a push rod to receive at least a portion of the valve lift profile.

[0011] In a specific embodiment that can combine the features of some or all of the above-mentioned embodiments, a rocker arm assembly is disclosed, which is capable of rotating around a rocker arm shaft and includes: a first part, which is configured to receive a valve lift profile; and a second part, which is configured to operably engage with one or more valves based on the valve lift profile, and the second part includes an idler assembly, which includes: a first shaft, which is confined in an idler hole of the idler assembly; a second shaft, which is disposed in the idler hole and is capable of longitudinal movement relative to the first shaft; and a biasing member, which is configured to bias the second shaft away from the first shaft.

[0012] In a specific embodiment that may combine the features of some or all of the above embodiments, the first shaft and the second shaft of the rocker arm assembly are colinearly arranged in the idler hole of the idler assembly. In a specific embodiment that may combine the features of some or all of the above embodiments, the second shaft is movable between a first position associated with a longitudinal gap in the idler hole between the first shaft and the second shaft, and a second position limited by contact between the first shaft and the second shaft in the idler hole.

[0013] In a specific embodiment in which the features of some or all of the above embodiments can be combined, the lost motion assembly of the rocker arm assembly is configured to be operably engaged with the one or more valves via a valve bridge. In a specific embodiment in which the features of some or all of the above embodiments can be combined, the second portion of the rocker arm assembly further comprises a switchable diaphragm box having a retractable plunger, and wherein the lost motion assembly is configured to absorb at least a portion of the valve lift profile. In a specific embodiment in which the features of some or all of the above embodiments can be combined, the switchable diaphragm box further comprises an actuator assembly configured to selectively extend the retractable plunger.

[0014] In a specific embodiment that can combine the features of some or all of the above embodiments, the actuator assembly of the switchable diaphragm is hydraulically actuated, and wherein the retractable plunger is selectively extended based on the hydraulic actuation of the actuator assembly. In a specific embodiment that can combine the features of some or all of the above embodiments, the retractable plunger is arranged in the plunger hole of the switchable diaphragm.

[0015] In a specific embodiment of the features of some or all of the embodiments in the above-mentioned embodiments can be combined, the idle hole is parallel to the plunger hole of the switchable diaphragm box. In a specific embodiment of the features of some or all of the embodiments in the above-mentioned embodiments can be combined, the idle hole is angled with the plunger hole of the switchable diaphragm box. In a specific embodiment of the features of some or all of the embodiments in the above-mentioned embodiments can be combined, the retractable plunger is configured to be operably engaged with a first valve of the one or more valves. In a specific embodiment of the features of some or all of the embodiments in the above-mentioned embodiments can be combined, the retractable plunger is configured to act on a pin to be operably engaged with the first valve, and the pin is slidably disposed in the valve bridge.

[0016] In a specific embodiment that may combine features of some or all of the above embodiments, a valve train system is disclosed, the valve train system comprising: a cam, the cam being provided with a valve lift profile; a plurality of valves, the plurality of valves comprising a first valve and a second valve; a valve bridge, the valve bridge being configured to be operably engaged with the plurality of valves; a rocker arm shaft; and a rocker arm assembly, the rocker arm assembly being rotatable about the rocker arm shaft, the rocker arm assembly comprising: a first portion, the first portion being configured to receive the valve lift profile from the cam; and a second portion, the second portion being configured to be operably engaged with the plurality of valves based on the valve lift profile, the second portion comprising: A switchable diaphragm cartridge configured to be operably engaged with the first valve, the diaphragm cartridge including an actuator assembly and a plunger, the plunger being configured to be selectively retractable based on actuation of the actuator assembly; and an idler assembly configured to be operably engaged with the valve bridge, the idler assembly being further configured to absorb at least a portion of the valve lift profile during an engine cycle, the idler assembly including: a first shaft confined within an idler hole of the idler assembly; a second shaft disposed within the idler hole, the second shaft being capable of longitudinal movement relative to the first shaft; and a biasing member configured to bias the second shaft away from the first shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be described in more detail below based on the exemplary drawings. The present invention is not limited to these exemplary embodiments. Other features and advantages of various embodiments of the present invention will become apparent by reading the following detailed description with reference to the accompanying drawings, which show the following:

[0018] Figure 1A and Figure 1B Schematic cross-sectional views of a rocker arm assembly corresponding to different cam rotational positions are shown according to certain embodiments.

[0019] Figure 2 A schematic diagram of an exemplary engine valve timing diagram for an engine cycle is shown according to certain implementations.

[0020] Figure 3A A schematic partial cross-sectional view of a rocker arm assembly according to certain embodiments is shown, with an enlarged exemplary switchable bellows further depicted in the inset.

[0021] Figure 3B A schematic partial cross-sectional view of a rocker arm assembly according to certain embodiments is shown.

[0022] Figure 4A Schematic exploded views of certain components of an exemplary lost motion assembly are shown, according to certain embodiments.

[0023] Figure 4B Schematic exploded views of certain components of an exemplary plunger retaining assembly are shown according to certain embodiments.

[0024] Figure 5A and Figure 5B An enlarged partial schematic cross-sectional view of an exemplary plunger retaining assembly according to certain embodiments is shown.

[0025] Figure 6 A schematic partial cross-sectional view of a rocker arm assembly is shown depicting an exemplary adjustment of a lost motion assembly according to certain embodiments.

[0026] 7A to 7D A schematic cross-sectional view of a lost motion assembly is shown, depicting an exemplary adjustment process, according to certain embodiments.

[0027] It should be noted that the drawings provided may be schematically illustrated rather than literally or precisely illustrated; components and aspects of the drawings may not necessarily be drawn to scale. In addition, while in many cases the same reference numerals may represent corresponding parts in different views, the same parts may not always have the same reference numerals in each view. DETAILED DESCRIPTION

[0028] According to various embodiments of the present disclosure, rocker arm assemblies and related mechanisms, devices and methods are provided herein. Although the present disclosure may include specific embodiments with specific features and feature combinations and specific use cases to provide a better understanding, it will be understood that the present disclosure is not limited to these specific exemplary embodiments or use cases.

[0029] In certain embodiments, the engine valve train may include a rocker arm for controlling the opening and closing of an intake valve and / or an exhaust valve of the engine. In certain embodiments, the rocker arm may include a reciprocating body that can convert the rotational motion of a camshaft of a rotating camshaft lobe into a motion that can control the opening and closing of the valve. In certain embodiments, the rocker arm may be configured to rotate around a rocker arm shaft, wherein a cam end of the rocker arm is configured to directly or indirectly contact one or more rotating cams, and a valve end is located at an end opposite to the cam end, and interfaces directly or indirectly (e.g., via a valve bridge) with one or more valves of the engine.

[0030] With reference to the accompanying drawings, Figure 1A and Figure 1BSchematic cross-sectional views of rocker arm assemblies corresponding to different cam rotational positions according to certain embodiments are shown. In certain embodiments, the valve train assembly 100 may include a rocker arm assembly 200 having a first portion 110 configured to receive a valve lift profile. In certain embodiments, the first portion 110 may correspond to a cam end that is configured to receive a valve lift profile from a suitable assembly, 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 in Figure 1A and Figure 1B As an example and not limitation, the first portion 110 may be configured to receive a valve lift profile via a push rod mechanism 170, such as in Figure 6 In certain embodiments, the rocker arm assembly 200 can be configured to rotate about the rocker arm shaft 130 .

[0031] In certain embodiments, the rocker arm assembly 200 may include a second portion 140 configured to operably engage one or more of the plurality of valves of the valve train assembly 100 based on the valve lift profile received by the rocker arm assembly 200. In certain embodiments, the second portion 140 may be configured to operably engage two valves, such as the first valve 160 and the second valve 165. In certain embodiments, the rocker arm assembly 200 may include a lost motion assembly 210. By way of example and not limitation, the lost motion assembly 210 may be configured to act directly or indirectly on one or more valves associated with the valve train assembly 100. By way of example and not limitation, such as in Figure 1A and Figure 1B As shown in , lost motion assembly 210 may be configured to act on valves 160 and 165, such as via valve bridge 145. In certain embodiments, lost motion assembly 210 may be configured to act at a common engagement location of valve bridge 145, such as a center portion of valve bridge 145.

[0032] In certain embodiments, the rocker arm assembly 200 may include a switchable diaphragm 230. In certain embodiments, the switchable diaphragm 230 may be configured to act directly or indirectly on one or more valves associated with the valve train assembly 100. By way of example and not limitation, such as in Figure 1A and Figure 1B As shown, the switchable membrane cartridge 230 can be configured to act on one of the plurality of valves, such as the first valve 160. In certain embodiments, the switchable membrane cartridge 230 can enter and / or engage with the first valve 160 via a suitable mechanism disposed in the valve bridge 145, such as a sliding pin 150 or a bridge mechanism (not shown).

[0033] It will be understood that although Figure 1A and Figure 1B The embodiments of the rocker arm assembly 200 shown in the figures may include both the lost motion assembly 210 and the switchable diaphragm box 230, and for ease of understanding, specific features and aspects may be described herein in specific combinations, but embodiments of the rocker arm assembly 200 having other combinations (such as one or the other of the lost motion assembly 210 and the switchable diaphragm box 230) are also possible and are fully contemplated in the present disclosure.

[0034] In certain embodiments, the rocker arm assembly 200 may be configured to allow for switchable engine braking functionality. In certain embodiments, the rocker arm assembly 200 may be configured as an integrated engine braking rocker arm. In certain embodiments, the rocker arm assembly 200 may be configured to engage with a plurality of exhaust valves. By way of example and not limitation, the first valve 160 may correspond to an engine braking exhaust valve, and the second valve 165 may correspond to a main exhaust valve.

[0035] In certain embodiments, the lost motion assembly 210 and / or the switchable diaphragm 230 may be used to selectively increase, decrease, and / or engage one or both of the first valve 160 and the second valve 165 based on the received valve profile. In certain embodiments, the rocker arm assembly 200 may be configured to receive a valve lift profile including a composite valve profile from the cam 120. As an example and not limitation, the composite valve profile may include a combination of valve lifts intended for operating a specific one or both of the first valve 160 and the second valve 165. In certain embodiments, the composite valve profile may include a normal exhaust valve profile or a main exhaust valve profile and an engine brake valve profile.

[0036] By way of example and not limitation, such as in an exemplary integrated engine braking rocker arm, the rocker arm assembly 200 may receive a valve lift profile from the cam 120 that includes a main lift segment 122, modified approach and fall segments (i.e., opening and closing ramps) of the main lift segment 122 based on engine braking demand, and / or one or more discrete engine braking lift segments 124. By way of example and not limitation, Figure 1B The cam 120 is shown with an exemplary main lift section 122 and an engine brake lift section 124 relative to a base circle 123. By way of example and not limitation, Figure 1B Also included are modified ramps leading to and away from the main lift section 122 relative to a non-engine brake exhaust profile (not shown).

[0037] In certain embodiments, the rocker arm assembly 200 may be configured such that the lost motion assembly 210 may absorb the portion of the composite valve lift profile corresponding to engine braking operation and only deliver the portion of the composite valve lift profile required for normal exhaust valve operation (i.e., non-engine braking operation, also referred to as a drive mode). In certain embodiments, the lost motion assembly 210 may be configured to act on the valve bridge 145 to operate the first valve 160 and the second valve 165. Thus, in certain embodiments, the lost motion assembly 210 may be configured to receive the composite valve lift profile, absorb the portion of the profile corresponding to engine braking, and impart a valve lift profile corresponding to normal exhaust valve operation to both exhaust valves.

[0038] In certain embodiments, the switchable membrane 230 can be configured to switch between a first state and a second state. By way of example and not limitation, in the first state, the switchable membrane 230 can be powered on and / or turned on. By way of example and not limitation, in the second state, the switchable membrane 230 can be powered off and / or turned off.

[0039] In a particular embodiment, the switchable diaphragm 230 may be configured to selectively act on a specified engine braking valve among the plurality of exhaust valves. In a particular embodiment associated with a rocker arm assembly 200 configured for engine braking, the switchable diaphragm 230 in a first state may correspond to an engaged engine braking mode. As an example and not limitation, in a first state, the switchable diaphragm 230 may be configured to engage with the first valve 160 to transmit and / or provide engine braking lift to the first valve 160. In a particular embodiment, the switchable diaphragm 230 may engage with the first valve 160 via a sliding pin 150 passing through the valve bridge 145 or using another suitable platform or mechanism.

[0040] In certain embodiments, the switchable diaphragm 230 in the second state may correspond to disengaging the engine braking mode, thereby switching to normal operation or mode (also referred to as the driving mode). As an example and not limitation, in the second state, the switchable diaphragm 230 may be configured to exit and / or disengage providing engine braking lift to the first valve 160.

[0041] Figure 2A schematic diagram of an engine valve timing diagram 300 in an engine cycle according to a particular embodiment is shown, which is depicted in a non-limiting example manner. As an example and not limitation, the illustration is indexed based on four intake-compression-power-exhaust cycles, where piston top dead center (TDC) and bottom dead center (BDC) events are marked accordingly. In a particular embodiment, in a drive mode (i.e., engine brake disengaged), the first valve 160 and the second valve 165 may operate corresponding to a common exhaust valve profile (such as a main exhaust valve profile 310). In a particular embodiment, such as for a particular integrated engine brake rocker arm embodiment, in a drive mode, the switchable diaphragm 230 may be withdrawn and / or disengaged; the rocker arm assembly 200 may receive a composite valve lift profile; the idler assembly 210 may absorb a portion of the composite profile corresponding to the engine brake lift, and the resulting main exhaust valve profile 310 may be transmitted to the first valve 160 and the second valve 165, such as via the valve bridge 145. By way of example and not limitation, the main exhaust lift 340 may correspond to the main lift section 122 of the cam 120 .

[0042] In certain embodiments, such as for certain integrated engine braking rocker arm embodiments, in engine braking mode, the switchable diaphragm 230 may be extended and / or engaged; the rocker arm assembly 200 may receive the composite valve lift profile; the lost motion assembly 210 may continue to absorb the portion of the composite profile corresponding to the engine braking lift, and may transmit the resulting main exhaust valve profile 310 to the first valve 160 and the second valve 165, such as via the valve bridge 145. As an example and not limitation, the main exhaust lift 340 may correspond to the main lift section 122 of the cam 120. Thus, in certain embodiments, the second valve 165 may continue to operate in engine braking as in the driving mode. Separately and / or additionally, in certain embodiments, the second valve 165 may be engaged by the switchable diaphragm 230 to effectively receive an engine braking valve profile, such as the engine braking valve profile 320. In certain embodiments, the engine braking valve profile 320 may include one or more discrete valve lift events, such as the brake gas recirculation lift 350 (in Figure 2 ). By way of example and not limitation, a brake gas recirculation event may charge additional mass to the engine cylinders and may occur when the pressure difference between the exhaust manifold and cylinder pressures is greatest. By way of example and not limitation, the brake gas recirculation lift 350 may correspond to a discrete engine brake lift segment 124.

[0043] By way of example and not limitation, the engine brake valve profile 320 may include one or more continuous, sloped, and / or offset valve lifts, such as a compression release 360 ​​(at Figure 2CR in FIG. 3 ). By way of example and not limitation, in some embodiments, compression release may generate primary engine braking force and opening timing may determine decompression pressure. In certain embodiments, portions of engine brake valve profile 320 may modify, intersect with, and / or otherwise correlate with portions of resulting exhaust valve profile 310.

[0044] Figure 3A A schematic partial cross-sectional view of a rocker arm assembly according to certain embodiments is shown, with an enlarged exemplary switchable bellows further depicted in the inset. Figure 3B A schematic partial cross-sectional view of a rocker arm assembly according to certain embodiments is shown.

[0045] As previously discussed, although the lost motion assembly 210 and the switchable diaphragm cartridge 230 are included in the rocker arm assembly 200 in the depicted embodiment for purposes of illustration and providing understanding, they need not be present together in every embodiment; each suitable aspect and feature of each of the lost motion assembly 210 and / or the switchable diaphragm cartridge 230 is considered herein, both individually and in combination.

[0046] In a particular embodiment, the lost motion assembly 210 may include a first shaft 214 and a second shaft 218 disposed in an lost motion hole 215 of the lost motion assembly 210. In a particular embodiment, the first shaft 214 may include a gap screw. In a particular embodiment, the first shaft 214 may be coupled to the nut 212. In a particular embodiment, the lost motion 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 be directly or indirectly engaged 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 the valve bridge 145. In a particular embodiment, the valve end of the second shaft 218 may include a suitable interface, such as a plunger end, a plunger pad, and / or an electronic foot (E-foot) (e.g., electronic foot 220).

[0047] In certain embodiments of the lost motion assembly 210, such as, by way of non-limiting illustrative example, Figure 3A , the first shaft 214 and the second shaft 218 of the lost motion assembly 210 can be relatively longitudinally constrained so that they can translate forward and backward relative to the aperture housing 222. In certain embodiments, the biasing member 216 can be disposed proximally of the first shaft 214 and / or coaxially with the first shaft. In certain embodiments, the biasing member 216 can be configured to act on the collar 219 of the second shaft 218.

[0048] In certain embodiments, the highest and / or fully retracted position of the lost motion assembly 210 may be indexed or limited by the collar 219 contacting a suitable flange or surface (such as provided on the aperture housing 222). By way of example and not limitation, once properly adjusted and / or calibrated, the electronic foot 220, the second shaft 218, the first shaft 214, and the nut 212 may translate relative to the aperture housing 222 without relative longitudinal displacement therebetween during operation. By way of example and not limitation, the electronic foot 220, the second shaft 218, the first shaft 214, and the nut 212 may move relative to the aperture housing 222 as a composite unit for longitudinal movement, thereby rising and falling between a retracted position and an extended position based on a balance of forces received by the electronic foot 220 and due to the biasing member 216 biasing toward the extended position.

[0049] Figure 4A Schematic exploded views of certain components of an exemplary lost motion assembly according to certain embodiments are shown. In certain embodiments of lost motion assembly 210, such as in the example of a non-limiting illustrative embodiment, Figure 3B , the second shaft 218 and the first shaft 214 can be disposed within the idle bore 215 such that the second shaft 218 can move longitudinally relative to the first shaft 214. By way of example and not limitation, while the first shaft 214 can be optionally adjusted, such as for calibration, maintenance, and / or other adjustments (e.g., clearance), in certain embodiments, during normal operation of the valve train assembly 100, the first shaft 214 can be constrained to a longitudinal position within the idle bore 215. In certain embodiments, the first shaft 214 and the second shaft 218 can be disposed co-linearly within the idle bore 215.

[0050] In certain embodiments, the second shaft 218 can be supported and / or prevented from removal by a suitable attachment, such as a clip 217, while freely translating longitudinally within the idle bore 215. In certain embodiments, the biasing member 216 can be configured to longitudinally separate the first shaft 214 and the second shaft 218, i.e., to increase the relative gap 224 between the first shaft 214 and the second shaft 218. In certain embodiments, the uppermost and / or fully retracted position of the second shaft 218 can be limited by contact with the fixed first shaft 214 within the idle bore 215. In certain embodiments, the relative gap 224 can be zero corresponding to the uppermost and / or fully retracted position of the second shaft 218 within the idle bore 215.

[0051] In certain embodiments, lost motion assembly 210 may include access port 290. By way of example and not limitation, access port 290 may be positioned to allow access therethrough to calibrate and / or otherwise adjust relative clearance 224 between first shaft 214 and second shaft 218, such as using calibration shims 292. By way of non-limiting example, in Figure 6290 is shown as a calibration shim 292 disposed through the entry port 290 to determine the relative gap 224. By way of example and not limitation, the relative gap 224 can be calibrated and / or otherwise adjusted to provide clearance adjustment to the idler assembly 210. By way of example and not limitation, the relative gap 224 can be calibrated or otherwise adjusted to determine and / or fix the maximum travel of the second shaft 218, i.e., the lowest and / or fully extended position of the second shaft 218. In certain embodiments, the first shaft 214 can be adjusted within the idler bore 215, such as with the aid of a nut 212, to calibrate, adjust, and / or otherwise fix the desired relative gap 224.

[0052] In certain embodiments, the switchable diaphragm 230 may include a suitable actuator assembly that is configured to selectively extend and retract a plunger, such as plunger 232. Although specific actuator assemblies are described in greater detail herein as non-limiting illustrations, the present disclosure fully contemplates any suitable actuator assembly for performing the functions disclosed herein. In certain embodiments, the switchable diaphragm 230 may include an electromagnetic actuator assembly that is configured to selectively extend and retract a plunger, such as plunger 232 (e.g., using a solenoid). In certain embodiments, the switchable diaphragm 230 may include a hydraulic actuator assembly, such as, as a non-limiting example, at least Figure 3A , Figure 3B and Figure 6 As shown in .

[0053] In certain embodiments, such as at least Figure 3A , Figure 3B and Figure 6 As shown in , the switchable membrane box 230 (provided with any suitable actuator assembly) may include a selectively retractable plunger 232. In a specific embodiment, based on the actuation of the actuator assembly, the plunger 232 can be retracted between a retracted position (away from the valve interface) and an extended position (toward the valve interface).

[0054] In certain embodiments, in the extended position, the plunger 232 can be configured to be substantially rigid, i.e., to support and resist forces received by contacting the corresponding valve interface. By way of example and not limitation, the plunger 232 in the extended position, which can correspond to an energized or open actuator assembly configuration and an engine braking mode, can be configured to contact the sliding pin 150 to transfer at least a portion of the received valve lift profile to the first valve 160.

[0055] In certain embodiments, in the retracted position, the plunger 232 can be configured to be substantially collapsed, soft and / or compliant, i.e., unable to support and / or resist forces resulting from contact with a corresponding valve interface. By way of example and not limitation, the plunger 232 in the retracted position, which can correspond to a de-energized or closed actuator assembly configuration and a normal or drive mode (engine brake off), can be configured to collapse under any incidental contact with the sliding pin 150.

[0056] In certain embodiments, such as Figure 3A (Illustration) and Figure 6 As shown in , the contact of the plunger 232 with the corresponding valve interface (such as the sliding pin 150) can apply significant forces, loads, impacts, impulses and / or wear to the switchable diaphragm 230. By way of example and not limitation, Figure 3A The enlarged illustration of 200 illustrates specific surfaces (marked by dashed ovals) that may be subject to significant wear and tear due to such contact. Although such contact is desired when the plunger 232 is extended by the actuator assembly, in certain embodiments, incidental contact between the plunger 232 and the corresponding valve interface continues to occur when the plunger 232 is in a collapsed or limp position because such embodiments may lack a positive means to adequately restrain, support and / or maintain the plunger 232 in the retracted position when the plunger 232 is collapsed or limp.

[0057] In certain embodiments, such as shown in FIG. 3B , the switchable membrane 230 may include a plunger fixing assembly 235 to limit, support and / or maintain the plunger 232 in a retracted position when the plunger 232 is folded or soft. In certain embodiments, the plunger fixing assembly 235 may be configured to release and / or allow extension of the plunger 232 through the switchable membrane 230 based on the extension force applied by the actuator assembly when it is energized or turned on to extend the plunger 232.

[0058] Figure 4B Schematic exploded views of certain components of an exemplary plunger fixing assembly according to certain embodiments are shown. In certain embodiments, the plunger fixing assembly 235 can include a plunger biasing member 238 and a retainer 236. In certain embodiments, the plunger biasing member 238 can be disposed between the plunger 232 and the retainer 236.

[0059] In certain embodiments, the idle hole 215 may be disposed parallel to the plunger hole and / or the plunger translation axis of the switchable membrane cartridge 230 .

[0060] Figure 5A and Figure 5B2 shows an enlarged schematic cross-sectional view of an exemplary plunger retaining assembly according to certain embodiments. In certain embodiments, the plunger biasing member 238 can be configured to bias the plunger 232 toward the retracted position of the plunger 232. In certain embodiments, the retainer 236 can include an annular and / or ring-like structure that can be configured to attach to hold the plunger biasing member 238 in place. In certain embodiments, such as in Figure 5A , when the actuator assembly is de-energized or turned off, the plunger biasing member 238 may be appropriately calibrated to withdraw the plunger 232 and / or fix the plunger in the retracted position of the plunger 232. In a particular embodiment, when the actuator assembly is energized or turned on, the plunger biasing member 238 may be additionally or separately appropriately calibrated to release, promote and / or allow the extension of the plunger 232. As an example and not limitation, corresponding to the energized or turned-on state of the actuator assembly, the extension force of the actuator assembly may overcome the force associated with the plunger biasing member 238, so that the plunger 232 can be extended to the extended position, such as to engage the valve interface. In a particular embodiment, the plunger biasing member 238 may include a spring.

[0061] It will be appreciated that although the plunger retaining assembly 235 is illustrated herein as a non-limiting example of a combination of a particular type of actuator assembly and / or switchable diaphragm cartridge 230, the features and functionality of the plunger retaining assembly 235 disclosed herein are fully contemplated in the context of securing any suitable type of plunger and / or for any suitable application, and are not limited to a particular type of diaphragm cartridge, or engine valve train and / or engine braking application.

[0062] Figure 6 A schematic partial cross-sectional view of a rocker arm assembly according to certain embodiments is shown, depicting an exemplary adjustment of a lost motion assembly. By way of example and not limitation, Figure 6 A gap adjustment process and / or calibration process may be depicted according to a particular embodiment of the lost motion assembly. As previously discussed, in a particular embodiment of the lost motion assembly 210, the access port 290 may allow for easy and quick access for calibration and / or other adjustments of the maximum extension of the second shaft 218 via adjustment of the relative gap 224. As an example and not limitation, a calibration shim 292 of an appropriate size may be inserted via the access port 290, and the first shaft 214 may be temporarily translated by loosening and tightening the nut 212 so that the relative gap 224 between the first shaft 214 and the second shaft 218 is appropriately fixed.

[0063] Alternatively or in addition, particular embodiments of the lost motion assembly 210 having a longitudinally fixed first shaft 214 may provide packaging benefits for installation and design freedom within a vertically narrow engine cylinder head space relative to a design of the lost motion assembly 210 in which the first shaft 214 is raised based on contact of the electronic foot 220 with a valve interface (such as the valve bridge 145).

[0064] In certain embodiments, such as at least Figure 3A and Figure 6 As shown in , the actuator assembly of the switchable diaphragm 230 can be hydraulically actuated, including a hydraulic actuator assembly 240. In a particular embodiment, the hydraulic actuator assembly 240 can be connected in fluid communication with a controllable high-pressure hydraulic fluid pipeline, such as through a hydraulic supply hole 260. As an example and not limitation, the hydraulic supply hole 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 hole 260.

[0065] In certain embodiments, the hydraulic actuator assembly 240 may include an upper chamber 242 connected to a hydraulic supply bore 260 and a lower chamber 244 controllably separated from the upper chamber 242 by a check valve 246. In certain embodiments, 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.

[0066] In certain embodiments, the 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 the check valve 246 such that the ball 248 may be used to close the flow passage unless the ball 248 is acted upon externally. In certain embodiments, a control pin 250 may be provided and biased toward the ball 248 by a control pin biasing member 252. In certain embodiments, the control pin biasing member 252 may include a spring.

[0067] In certain embodiments, during operation in the de-energized or closed state of the switchable diaphragm 230, the supply of pressurized hydraulic fluid to the hydraulic actuator assembly 240 is shut off based on closing the engine's oil control valve, thereby shutting off the supply of pressurized hydraulic fluid to the hydraulic actuator assembly 240 via the hydraulic supply hole 260. Therefore, in certain embodiments, the control pin 250 can push the ball 248 away 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 a force on a valve interface (such as the sliding pin 150). By way of example and not limitation, based on a control pin 250 that holds ball 248 open, ball 248 can be switchably rendered inoperable as a hydraulic check valve mechanism, such as by selectively opening and closing a fluid flow passage of check valve 246 in response to an effective force and / or pressure acting on ball 248 .

[0068] In certain embodiments, during operation of the energized or open state of the switchable diaphragm 230, based on opening the oil control valve of the engine, the supply of pressurized hydraulic fluid to the hydraulic actuator assembly 240 can be turned on, thereby connecting the hydraulic actuator assembly 240 to the pressurized hydraulic fluid supply via the hydraulic supply hole 260 and thereby pressurizing the hydraulic fluid in the upper chamber 242. Therefore, in certain embodiments, such as based on the pressure of the pressurized hydraulic fluid pressure in the upper chamber 242, the control pin 250 can be urged to resist the force of the control pin biasing member 252, thereby disengaging or withdrawing the control pin 250 from contact with the ball 248.

[0069] Therefore, in a specific embodiment, in a state where the control pin 250 can withdraw from contact with the ball 248 by a specific manner of switching on the switchable diaphragm 230, the ball 248 can be allowed and / or promoted to respond based on the effective differential force acting on the ball 248 to selectively open and close the fluid flow passage of the check valve 246. As an example and not limitation, in a state where the control pin 250 can withdraw from acting on 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 and not limitation, in a state in which the control pin 250 can be withdrawn from acting on 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).

[0070] Thus, in certain embodiments, the lower chamber 244 may include hydraulic fluid at an effective pressure at least equal to the effective pressure of the upper chamber 242 to maintain the ball 248 to close the fluid flow passage of the check valve 246, such as to maintain the plunger 232 in the extended position. In certain embodiments, 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 to enter the lower chamber 244, such as to extend the plunger 232 and / or maintain the extension of the plunger, and then closed. In certain embodiments, one or more additional or alternative forces, such as forces generated by suitable biasing members, may contribute to one or more effective hydraulic forces to operably determine the open or closed state of the ball 248. In a particular embodiment, when the plunger 232 receives a force from a valve interface (such as a sliding pin 150), the corresponding rise in effective hydraulic fluid pressure in the lower chamber 244 relative to the upper chamber 242 can be used to keep the ball 248 closed, sealing the lower chamber 244 and trapping the hydraulic fluid therein, thereby allowing the plunger 232 to remain rigidly extended to resist and apply force relative to the valve interface (such as a sliding pin 150).

[0071] Figure 6 Also shown is a non-limiting example of a rocker arm assembly 200 configured to receive a valve profile from the pushrod mechanism 170 .

[0072] 7A to 7DA schematic cross-sectional view of a lost motion assembly according to certain embodiments is shown, depicting an exemplary adjustment process. By way of example and not limitation, 7A to 7D The gap adjustment process and / or calibration process according to a specific embodiment of the idler assembly can be described. In certain embodiments, features such as those disclosed herein can significantly simplify and speed up the maintenance, calibration and / or adjustment process of the idler assembly 210, such as gap setting. By way of example and not limitation, as in Fig. 7A As shown in , the nut 212 can be rotated to loosen the idler assembly 210. By way of example and not limitation, as shown in Figure 7B As shown in , the first shaft 214 can then be rotated upward to increase the relative gap 224 between the first shaft 214 and the second shaft 218. As an example and not limitation, as shown in Figure 7C As shown in FIG, a suitable calibration shim 292 (such as a slide gauge including a calibration) can be inserted through the access port 290, and the first shaft 214 can be tightened until it contacts a hard stop corresponding to the calibration shim 292. As an example and not limitation, as shown in FIG. Fig.7D As shown, the nut 212 may then be tightened to complete the gap adjustment and setting of the switchable bellows 230 .

[0073] other

[0074] The above description of these embodiments has been provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the present disclosure. The individual elements or characteristic structures of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable and can be used in selected embodiments where applicable, even if not specifically shown or described. It can also be changed in many ways. Such variants should not be considered to be out of the present disclosure, and all such modifications are intended to be included within the scope of the present disclosure.

[0075] Although the present invention has been shown and described in detail in the accompanying drawings and the foregoing description, such illustration and description are considered to be illustrative or exemplary rather than restrictive. It should be understood that those of ordinary skill in the art can make changes and modifications within the scope of the appended claims. In particular, the present invention encompasses other embodiments with any combination of features from the different embodiments described above and below. In addition, the statements characterizing the present invention made herein refer to an embodiment of the present invention, not necessarily all embodiments.

[0076] The terms used in the claims should be interpreted as having the broadest reasonable interpretation consistent with the foregoing description. For example, the use of the article "one" or "the" when introducing an element should not be interpreted as excluding multiple elements. Similarly, the expression of "or" should be interpreted as inclusive, so that the expression of "A or B" does not exclude "A and B", unless it is clear from the context or the foregoing description that only one of A and B is intended. In addition, the expression "at least one of A, B and C" should be interpreted as one or more of a 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 categories or otherwise. In addition, the expression of "A, B and / or C" or "at least one of A, B or C" should be interpreted as including any single entity from the listed elements (e.g., A), any subset from the listed elements (e.g., A and B), or the entire list of elements A, B and C.

[0077] Numerical ranges recited in this application should be interpreted as including the endpoints of the ranges. Specific axes, such as one or more transverse and / or longitudinal axes, which may be omitted in some of the illustrations herein, should be interpreted as being present in each illustration or instance where relevant or mentioned.

Claims

1. A rocker arm assembly, the rocker arm assembly being rotatable about a rocker arm shaft and characterized in that include: a first portion configured to receive a valve lift profile; and a second portion configured to operably engage one or more valves of the plurality of 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 membrane box, the switchable membrane box comprising: an actuator assembly switchable between a first state and a second state; a plunger disposed in the plunger bore, the plunger being selectively retractable between a retracted position and an extended position upon actuation of the actuator assembly; and a plunger retaining assembly comprising a plunger biasing member and a retainer, the plunger biasing member being disposed between the plunger and the retainer and being configured to bias the plunger toward the retracted position, Corresponding to the first state of the actuator assembly, the plunger biasing member is configured to secure the plunger in the retracted position.

2. The rocker arm assembly according to claim 1, characterized in that: Corresponding to the second state of the actuator assembly, 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 according to claim 1, characterized in that: The plunger biasing member includes a spring.

4. The rocker arm assembly according to claim 1, characterized in that: The idle running assembly comprises: a first shaft constrained within an idler bore of the idler assembly; a second shaft disposed in the idler hole, the second shaft being able to move longitudinally relative to the first shaft; and A biasing member is configured to bias the second shaft away from the first shaft.

5. The rocker arm assembly according to claim 4, characterized in that: The second shaft is movable between a first position associated with longitudinal clearance within the idler bore between the first shaft and the second shaft and a second position limited by contact within the idler bore between the first shaft and the second shaft.

6. The rocker arm assembly according to claim 1, characterized in that: The actuator assembly of the switchable bellows is hydraulically actuated, and the plunger is selectively retractable based on the hydraulic actuation of the actuator assembly.

7. The rocker arm assembly according to claim 1, characterized in that: The first portion includes a roller configured to engage a cam to receive at least a portion of the valve lift profile.

8. The rocker arm assembly according to claim 1, characterized in that: The first portion is configured to operably engage a pushrod to receive at least a portion of the valve lift profile.

9. A rocker arm assembly, the rocker arm assembly being rotatable about a rocker arm shaft and characterized in that include: a first portion configured to receive a valve lift profile; and a second portion configured to operably engage one or more valves based on the valve lift profile, the second portion comprising a lost motion assembly, the lost motion assembly comprising: a first shaft constrained within an idler bore of the idler assembly; a second shaft disposed in the idler hole, the second shaft being able to move longitudinally relative to the first shaft; and A biasing member is configured to bias the second shaft away from the first shaft.

10. The rocker arm assembly according to claim 9, characterized in that: The first shaft and the second shaft are co-linearly disposed within the idler bore of the idler assembly.

11. The rocker arm assembly according to claim 9, characterized in that: The second shaft is movable between a first position associated with longitudinal clearance within the idler bore between the first shaft and the second shaft and a second position limited by contact between the first shaft and the second shaft within the idler bore.

12. The rocker arm assembly according to claim 9, characterized in that: The lost motion assembly is configured to operably engage the one or more valves via a valve bridge.

13. The rocker arm assembly according to claim 9, characterized in that: The second portion further includes a switchable diaphragm having a retractable plunger, and the lost motion assembly is configured to absorb at least a portion of the valve lift profile.

14. The rocker arm assembly according to claim 13, characterized in that: The switchable bellows also includes an actuator assembly configured to selectively extend the retractable plunger.

15. The rocker arm assembly according to claim 14, characterized in that The actuator assembly of the switchable bellows is hydraulically actuated, and the retractable plunger is selectively extended based on the hydraulic actuation of the actuator assembly.

16. The rocker arm assembly according to claim 13, characterized in that The retractable plunger is arranged in the plunger hole of the switchable membrane box.

17. The rocker arm assembly according to claim 16, characterized in that The idle hole is parallel to the plunger hole of the switchable membrane box.

18. The rocker arm assembly according to claim 13, characterized in that The retractable plunger is configured to operably engage a first valve of the one or more valves.

19. The rocker arm assembly according to claim 18, characterized in that The retractable plunger is configured to act on a pin slidably disposed within a valve bridge to operatively engage the first valve.

20. A valve train system, characterized in that include: A cam, wherein the cam is provided with a valve lift profile; a plurality of valves, the plurality of valves comprising a first valve and a second valve; a valve bridge configured to operably engage the plurality of valves; Rocker arm shaft; and A rocker arm assembly, wherein the rocker arm assembly is rotatable around the rocker arm shaft, and the rocker arm assembly comprises: a first portion configured to receive the valve lift profile from the cam; and a second portion configured to operably engage with the plurality of valves based on the valve lift profile, the second portion comprising: a switchable diaphragm configured to be operably engaged with the first valve, the diaphragm comprising an actuator assembly and a plunger, the plunger being configured to be selectively retractable based on actuation of the actuator assembly; and a lost motion assembly configured to operably engage 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 comprising: a first shaft constrained within an idler bore of the idler assembly; a second shaft disposed in the idler hole, the second shaft being able to move longitudinally relative to the first shaft; and A biasing member is configured to bias the second shaft away from the first shaft.

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