CN114622963B

CN114622963B - Box assembly, rocker arm assembly and valve assembly

Info

Publication number: CN114622963B
Application number: CN202210300505.4A
Authority: CN
Inventors: M·赛瑟
Original assignee: Eaton Intelligent Power Ltd
Current assignee: Eaton Intelligent Power Ltd
Priority date: 2016-04-07
Filing date: 2017-12-05
Publication date: 2024-04-05
Anticipated expiration: 2037-12-05
Also published as: CN113803127B; WO2017177102A1; CN109154216B; CN109154216A; CN114622963A; CN113803127A; DE112017001251T5

Abstract

A valve assembly constructed in accordance with one example of the present disclosure includes primary and secondary exhaust rocker arm assemblies, first and second latch assemblies, and an actuation assembly. The main exhaust rocker arm assembly has a first main exhaust rocker arm and a second main exhaust rocker arm. The secondary exhaust rocker arm assembly has a first secondary exhaust rocker arm and a secondary exhaust rocker arm. The actuation assembly has an actuator, a primary arm, and a secondary arm. The actuator rotates an exhaust cam lever including a first cam and a second cam. The main arm rotates based on movement to the first cam, thereby moving the first latch assembly between a first position and a second position. The secondary arm rotates based on movement of the second cam, thereby moving the second latch assembly between a first position and a second position.

Description

Box assembly, rocker arm assembly and valve assembly

The present application is a divisional application of chinese patent application 201780085111.9 entitled "heavy duty variable valve actuation" with application date of 2017, 12, 05.

Cross Reference to Related Applications

The present application claims priority from U.S. provisional application Ser. No. 62/430,102, filed on day 5, 12, 2016. The disclosures of the above applications are incorporated herein by reference.

Technical Field

The present disclosure relates generally to cartridge assemblies, rocker arm assemblies, and valve assemblies.

Background

The combustion cycle on a four-stroke internal combustion engine may be modified to achieve various desired results such as improved fuel economy. In one approach, the expansion stroke is increased relative to the compression stroke. The effect is sometimes referred to as the Miller (Miller) cycle or the Atkinson (Atkinson) cycle. The miller cycle and the atkinson cycle may be implemented by closing the intake valve earlier than a standard or Otto (Otto) cycle ("base") having a shorter intake valve lift duration ("EIVC") than standard or by closing the intake valve after a longer intake valve lift profile ("LIVC") than standard.

Various systems have been developed for altering valve lift characteristics of internal combustion engines. Such systems are commonly referred to as Variable Valve Lift (VVL), variable Valve Timing (VVT) or Variable Valve Actuation (VVA), improve fuel economy, reduce emissions, and improve driving comfort over a range of speeds.

Discrete variable valve lift may be achieved through the use of a switching rocker arm technique. Switching rocker arms allow control of valve actuation by alternating between a latched state and an unlatched state, which typically involves an inner arm and an outer arm. In some cases, the arms engage different cam lobes, such as a low-lift lobe, a high-lift lobe, and a no-lift lobe. A mechanism is required to switch the rocker mode in a manner suitable for the operation of the internal combustion engine.

In addition to the wheel brakes, the compression engine brake may be used as an auxiliary brake on relatively large vehicles, for example powered by a heavy or medium duty diesel engine. When the piston in an engine cylinder is close to the top dead centre position of its compression stroke, the compression engine brake system is arranged to effect additional opening of the exhaust valve of said cylinder at start-up, so that compressed air can be released through said exhaust valve. This allows the engine to act as a power consuming air compressor, slowing the vehicle.

In a typical valve assembly used with a compression engine brake, the exhaust valves are actuated by rocker arms that engage the exhaust valves via valve bridges. The rocker arm rocks in response to rotating a cam on the camshaft and presses down the exhaust valve to open it. In some examples, a valve bridge may be disposed between a rocker arm and a pair of exhaust valves. Hydraulic lash adjusters may also be provided in the valve assembly to remove any lash or play created between components in the valve assembly.

The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

Disclosure of Invention

A valve assembly constructed in accordance with one example of the present disclosure includes primary and secondary exhaust rocker arm assemblies, first and second latch assemblies, and an actuation assembly. The main exhaust rocker arm assembly has a first main exhaust rocker arm and a second main exhaust rocker arm. The first latch assembly is selectively movable between a first position in which the first and second main exhaust rocker arms are locked for simultaneous rotation and a second position in which one of the first and second main exhaust rocker arms rotates relative to the other of the first and second main exhaust rocker arms. The secondary exhaust rocker arm assembly has a first secondary exhaust rocker arm and a secondary exhaust rocker arm. The second latch assembly is selectively movable between a first position in which the first and second secondary exhaust rocker arms are locked for simultaneous rotation and a second position in which one of the first and second secondary exhaust rocker arms rotates relative to the other of the first and second secondary exhaust rocker arms. The actuation assembly selectively moves the first and second latch assemblies between respective first and second positions. The actuation assembly has an actuator, a primary arm, and a secondary arm. The actuator rotates an exhaust cam lever including a first cam and a second cam. The main arm rotates based on movement to the first cam such that the first latch assembly moves from the first position to the second position. The secondary arm rotates based on movement of the second cam such that the second latch assembly moves from the first position to the second position.

According to additional features, the actuation assembly further includes a link arm disposed between the actuator and the exhaust cam lever, wherein translation of the link arm causes rotation of the exhaust cam lever. The first latch assembly includes an inner pin and an outer pin slidably disposed in the main exhaust rocker arm assembly. The inner and outer pins are misaligned with the corresponding first and second main exhaust rocker arms when the first latch assembly is in the first position, and the inner and outer pins are aligned with the corresponding first and second main exhaust rocker arms when the second latch assembly is in the second position.

The second latch assembly includes an inner pin and an outer pin slidably disposed in the main exhaust rocker arm assembly. The inner and outer pins are misaligned with the corresponding first and second secondary exhaust rocker arms when the second latch assembly is in the first position, and the inner and outer pins are aligned with the corresponding first and second secondary exhaust rocker arms when the second latch assembly is in the second position. The main arm includes a first main swing arm and a second main swing arm coupled by a main biasing member. The primary biasing member urges the first primary swing arm into engagement with the first cam.

According to other features, the first leaf spring urges the first latch assembly back to the first position. The second leaf spring urges the second latch assembly back to the first position. The secondary arm includes a first secondary swing arm and a second secondary swing arm coupled by a second biasing member. The secondary biasing member urges the first secondary swing arm into engagement with the second cam.

In other features, the valve assembly further comprises a primary intake rocker arm assembly, a third latch assembly, a secondary intake rocker arm assembly, and a fourth latch assembly. The main intake rocker arm assembly has a first main intake rocker arm and a second main intake rocker arm. The third latch assembly is selectively movable between a first position in which the first and second main intake rocker arms are locked for simultaneous rotation and a second position in which one of the first and second main intake rocker arms rotates relative to the other of the first and second main intake rocker arms. The secondary intake rocker arm assembly has a first secondary intake rocker arm and a second secondary intake rocker arm. The fourth latch assembly is selectively movable between a first position in which the first and second intake rocker arms are locked for simultaneous rotation and a second position in which one of the first and second intake rocker arms rotates relative to the other of the first and second intake rocker arms. The actuation assembly further includes an intake cam lever. The actuator rotates both the exhaust cam lever and the intake cam lever.

In additional features, the main exhaust rocker arm assembly is configured to selectively operate in a standard exhaust lift and Early Exhaust Valve Opening (EEVO). The main intake rocker arm assembly is configured to selectively operate in an Early Intake Valve Closing (EIVC) and a Late Intake Valve Closing (LIVC). The secondary exhaust rocker arm assembly and the secondary intake rocker arm assembly are configured to selectively operate in two-stroke engine braking (TSEB). The first main exhaust rocker arm has a rocker arm body defining an oil supply passage and an opening receiving an exhaust rocker shaft.

According to additional features, the first main exhaust rocker arm further includes a first cartridge assembly disposed on the rocker arm body and configured to selectively transfer oil to and from the oil supply passage. The cartridge assembly includes a plunger assembly and a spool valve assembly. The plunger assembly has a plunger that selectively translates within the plunger chamber between an extended rigid position based on the plunger chamber being pressurized with oil and a retracted non-rigid position based on the plunger chamber being depressurized, the plunger moving the engine valve toward the open position. The spool valve assembly moves between a first position and a second position based on oil communicated in the oil supply passage. The spool valve assembly has a spool valve that is selectively movable between a closed position and an open position wherein oil flows into the plunger chamber. The rocker arm assembly moves sequentially along (i) a first valve lift profile in which pressurized oil is delivered from the oil supply passage, (ii) a reset valve lift profile in which pressurized oil is not delivered from the oil supply passage, and (iii) a valve closing profile in which the spool valve assembly moves into the second position such that the spool valve is opened, the pressure chamber is pressurized and the plunger moves to the extended rigid position.

In an additional feature, the spool valve assembly moves into the second position based on the oil supply passage of the rocker arm body being aligned with the actuation oil supply passage on the exhaust rocker shaft. The spool valve assembly moves into the first position based on the oil supply passage of the rocker arm body being aligned with the reset drain passage on the rocker shaft. The actuator may be a pneumatic actuator.

Drawings

The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

FIG. 1 is a first perspective view of a partial valve assembly having two exhaust rocker arm assemblies configured for opening and closing respective exhaust valves and two intake rocker arm assemblies for opening and closing respective intake valves, according to one example of the present disclosure;

FIG. 2 is a second perspective view of the partial valve assembly shown in FIG. 1;

FIG. 3 is a plan view of the partial valve assembly of FIG. 1, and showing an exemplary exhaust lift profile and intake lift profile that may be implemented using an exhaust rocker arm assembly and an intake rocker arm assembly, including a standard exhaust lift profile, an Early Exhaust Valve Opening (EEVO) profile, two-stroke engine braking (TSEB), early Intake Valve Closing (EIVC), and Late Intake Valve Closing (LIVC);

FIG. 4 is a table illustrating operating modes of a valve assembly that may be used with the present disclosure;

FIG. 5 is a perspective detail view illustrating a primary and secondary exhaust rocker arm assembly having an exhaust side deactivation assembly constructed in accordance with one example of the present disclosure;

FIG. 6 is a plan view of the exhaust side deactivation assembly of FIG. 5 showing the primary and secondary exhaust rocker arm assemblies in a deactivated position;

FIG. 7 is a cross-sectional view of the latch assembly taken along line 7-7 of FIG. 6 and showing the latch assembly in a first position;

FIG. 8 is a plan view of the primary and secondary exhaust rocker arm assemblies and the exhaust side deactivation assembly of FIG. 5 showing the primary exhaust latch actuation assembly in an activated position;

FIG. 9 is a cross-sectional view of the latch assembly taken along line 9-9 of FIG. 8 and showing the latch assembly in a second position;

FIG. 10 is a perspective view of the exhaust side deactivation module of FIG. 5;

FIG. 11 is a plan view of the exhaust side disabling assembly of FIG. 10;

FIG. 12 is a graph illustrating reset function in engine braking and driving modes on a main exhaust rocker arm assembly constructed in accordance with the teachings of the present invention;

FIG. 13 is a cross-sectional view of a rocker arm assembly constructed in accordance with the present disclosure and shown in an engine braking mode;

FIG. 14 is a cross-sectional view of a rocker arm assembly constructed in accordance with the present disclosure and shown in a drive mode with lost motion;

FIG. 15 is a front perspective view of the rocker arm assembly constructed in accordance with the present disclosure and showing the oil supply passage initially aligned with the return drain passage;

FIG. 16 is a front perspective view of the rocker arm assembly constructed in accordance with the present disclosure and showing the rocker arm assembly after completion of the reset function; and is also provided with

Fig. 17 is a perspective view of a rocker arm assembly constructed in accordance with the present disclosure and showing the rocker arm assembly rotated further clockwise.

Detailed Description

During 2021 to 2027, heavy vehicles must increase fuel efficiency by 2.5% per year. The present disclosure provides embodiments and strategies for achieving more fuel efficient valve actuation. As will be appreciated from the discussion below, the present disclosure provides a heavy duty variable valve assembly 10 that provides LIVC, EIVC, standard exhaust valve opening, early Exhaust Valve Opening (EEVO), two-stroke engine braking (TSEB), and Cylinder Deactivation (CDA) in one system.

The heavy duty variable valve assembly 10 is based on a dual overhead cam valve train layout of four rocker arm assemblies for each cylinder. In the specific examples discussed herein, a portion of a valve assembly is shown utilizing engine braking in a three cylinder bank portion configured for a six cylinder engine. However, it should be appreciated that the present teachings are not so limited. In this regard, the present disclosure may be used in any valve assembly that utilizes variable valve actuation. The partial valve assembly 10 shown in the figures provides four rocker arm assemblies for each cylinder. The following discussion focuses, for simplicity, on the operation of these four rocker arm assemblies configured for use on a single cylinder. It should be appreciated that, although not shown, four rocker arm assemblies are further provided for each of the remaining cylinders.

The valve assembly 10 includes a primary exhaust rocker arm assembly 20, a secondary exhaust rocker arm assembly 22, a primary intake rocker arm assembly 30, and a secondary intake rocker arm assembly 32. The main exhaust rocker arm assembly 20 and the main intake rocker arm assembly 30 incorporate reset function boxes 34 and 36, respectively. The secondary exhaust rocker arm assembly 22 and the secondary intake rocker arm assembly 32 are configured for selective operation in a two-stroke engine braking mode.

Each of the rocker arm assemblies 20, 22, 30, and 32 incorporates a deactivated scissor type configuration. Further explained, the main exhaust rocker arm assembly 20 commonly includes a first main exhaust rocker arm 20a and a second main exhaust rocker arm 20b. The secondary exhaust rocker arm assembly 22 collectively includes a first secondary exhaust rocker arm 22a and a second secondary exhaust rocker arm 22b. The main intake rocker arm assembly 30 commonly includes a first main intake rocker arm 30a and a second main intake rocker arm 30b. The secondary intake rocker arm assembly 32 collectively includes a first secondary intake rocker arm 32a and a second secondary intake rocker arm 32b.

The exhaust valves 40, 42 are opened and closed by the primary and secondary exhaust rocker arm assemblies 20, 22. Similarly, the intake valves 44, 46 are opened and closed by the primary intake rocker arm assembly 30 and the secondary intake rocker arm assembly 32. An intake rocker shaft (removed for clarity) is received by the valve assembly carrier and supports rotation of the primary intake rocker arm assembly 30 and the secondary intake rocker arm assembly 32. The exhaust rocker shaft 48 is received by the valve assembly carrier and supports rotation of the primary and secondary exhaust rocker arm assemblies 20, 22. In the example shown, the main exhaust rocker arm assembly 20 opens and closes the exhaust valves 40, 42 via a valve bridge 50. The main intake rocker arm assembly 30 opens and closes the intake valves 44, 46 via a valve bridge 52. The secondary exhaust rocker arm assembly 22 may selectively open the exhaust valve 42 during two-stroke engine braking. The secondary intake rocker arm assembly 32 may selectively open the intake valve 46 during two-stroke engine braking. The exhaust valves 40, 42 and intake valves 44, 46 are biased closed by valve springs (removed for clarity).

The main exhaust rocker arm assembly 20 rotates about the exhaust rocker shaft 48 based on the lift profile of a main exhaust cam 54a (FIG. 2) that rotates with an exhaust camshaft 55 a. The secondary exhaust rocker arm assembly 22 rotates about the exhaust rocker shaft 48 based on the lift profile of the secondary exhaust cam 54b that rotates with the exhaust camshaft 55 a. The main exhaust rocker arm assembly 20 has a roller 56a that rotatably engages the main exhaust cam 54 a. The secondary exhaust rocker arm assembly 22 has a roller 56b that rotatably engages the secondary exhaust cam 54 b. The main intake rocker arm assembly 30 rotates about an intake rocker shaft based on the lift profile of a main intake cam 57a that rotates with an intake camshaft 55 b. The secondary intake rocker arm assembly 32 rotates about an intake rocker shaft based on the lift profile of the secondary intake cam 57b that rotates with the intake camshaft 55 b. The main intake rocker arm assembly 30 has a roller 58a (fig. 1) that rotatably engages a main intake cam 57a (fig. 2). The secondary intake rocker arm assembly 32 has a roller 57b that rotatably engages a secondary intake cam 57b.

As will be appreciated from the following discussion and as shown in fig. 3 and 4, the main exhaust rocker arm assembly 20 may be configured for operation along a standard exhaust valve lift profile or an early exhaust valve lift profile. The secondary exhaust rocker arm assembly 22 may be configured for operation in a two-stroke engine brake exhaust profile. The main intake rocker arm assembly 30 may be configured for operation along an Early Intake Valve Closing (EIVC) lift profile or a late intake valve closing profile (LIVC). The secondary intake rocker arm assembly 32 may be configured for operation in a two-stroke engine braking intake profile. As discussed herein with respect to fig. 12-16, the main exhaust rocker arm assembly 20 and the main intake rocker arm assembly 30 are actuated based on pressurized oil (two oil control valves). When the main exhaust rocker arm assembly 20 is operating in EEVO, a (first) oil control valve (exhaust side) is positioned upstream to direct oil flow into the cartridge 34. However, a (second) oil control valve (intake side) is positioned downstream of the cartridge 36 to control the discharge of oil from the cartridge 36. Deactivation of two-stroke engine braking and cylinder deactivation is achieved using electromechanical actuation assembly 59.

Each rocker arm pair 20a, 20b;22a, 22b;30a, 30b; and 32a, 32b have latch assemblies 60, 62, 64 and 66 that move independently based on electromechanical actuating assembly 59 to allow either simultaneous rotation of each rocker arm pair or relative rotation of the second rocker arm and the first rocker arm. More clearly explained, the latch assembly 60 moves between a first position (fig. 7) that allows the rocker arm pairs 20a and 20b to rotate simultaneously and a second position (fig. 9) that allows the second main exhaust rocker arm 20b to rotate relative to the first main exhaust rocker arm 20a. As mentioned in fig. 6 to 9, the latch assembly 60 is shown in a first position (fig. 7) that allows the rocker arm pairs 20a and 20b to rotate simultaneously and in a second position (fig. 9) that allows the second main exhaust rocker arm 20b to rotate relative to the first main exhaust rocker arm 20a (the lost motion stroke causes no valve actuation). It should be appreciated that each of the other latch assemblies 60, 62 and 66 operate similarly.

The latch assembly 62 moves between a first position allowing the rocker arm pairs 22a and 22b to rotate simultaneously and a second position allowing the second exhaust rocker arm 22b to rotate relative to the first exhaust rocker arm 22a (the lost motion stroke causes no valve actuation). The latch assembly 64 moves between a first position allowing simultaneous rotation of the rocker arm pairs 30a and 30b and a second position allowing rotation of the second main intake rocker arm 30b relative to the first main intake rocker arm 30a (the lost motion stroke causes no valve actuation). The latch assembly 66 moves between a first position allowing simultaneous rotation of the rocker arm pairs 32a and 32b and a second position allowing rotation of the second intake rocker arm 32b relative to the first intake rocker arm 32a (the lost motion stroke causes no valve actuation).

The first and second main exhaust rocker arms 20a, 20b may rotate together when the main exhaust latch assembly 60 is in the normal latched position. The second main exhaust rocker arm 20b is rotatable relative to the first main exhaust rocker arm 20a when the main exhaust latch assembly 60 is in the unlatched position. The coil return spring 61 biases the second main exhaust rocker arm 20b rearward against the main exhaust cam 54 a. The first and second secondary exhaust rocker arms 22a, 22b may rotate together when the secondary exhaust latch assembly 62 is in the normal latched position. The second secondary exhaust rocker arm 22b may rotate relative to the first secondary exhaust rocker arm 22a when the secondary exhaust latch assembly 62 is in the unlatched position. The coil return spring 63 biases the second secondary exhaust rocker arm 22b rearward against the secondary exhaust cam 54 b.

The first and second main intake rocker arms 30a, 30b may rotate together when the main intake latch assembly 64 is in the normal latched position. The second main intake rocker arm 30b is rotatable relative to the first main intake rocker arm 30a when the main intake latch assembly 64 is in the unlatched position. The coil return spring 65 biases the second main intake rocker arm 30b rearward against the main intake cam 57 a. The first and second intake rocker arms 32a, 32b may rotate together when the secondary intake latch assembly 66 is in the normal latched position. The second secondary intake rocker arm 32b may rotate relative to the first secondary intake rocker arm 32a when the secondary intake latch assembly 66 is in the unlatched position. The coil return spring 67 biases the second intake rocker arm 32b rearward against the second intake cam 57b.

Returning now to fig. 1 and 2, electromechanical actuating assembly 59 will be further described. The electromechanical actuation assembly 59 generally includes an exhaust side deactivation assembly 70 and an intake side deactivation assembly 72. Generally, the electromechanical actuating assembly 59 includes a common pneumatic actuator 80 that translates a link arm 82. It should be appreciated that other actuators than pneumatic actuators may alternatively be used. For example, the actuator may be electrohydraulic. Translation of the link arm 82 causes simultaneous rotation of the exhaust side cam lever 86 and the intake side cam lever 88. The following description will focus on the exhaust side disabling assembly 70. However, it should be appreciated that additional exhaust side deactivation components are provided for each cylinder and operate similarly. Likewise, the intake side deactivation module 72 operates similarly to other intake side deactivation modules on other cylinders.

Referring now specifically to FIG. 5, the exhaust side cam lever 86 extends through the bracket assembly 90 and includes a first cam 100 and a second cam 102. The exhaust side disabling assembly 70 includes a primary exhaust latch actuation assembly 110 and a secondary exhaust latch actuation assembly 112. The main exhaust latch actuation assembly 110 moves the main exhaust latch assembly between a latched position and an unlatched position. The secondary exhaust latch actuation assembly 112 moves the secondary exhaust latch assembly between a latched position and an unlatched position. The main exhaust latch actuation assembly 110 includes a first main swing arm 120, a second main swing arm 122, and a main biasing member 124. The first and second main swing arms 120, 122 are rotatably coupled about a pivot 126 disposed on the carriage assembly 90. The secondary exhaust latch assembly 112 includes a first secondary swing arm 130, a second secondary swing arm 132, and a secondary biasing member 134. The first swing arm 130 and the second swing arm 132 are rotatably coupled about a pivot 136 disposed on the bracket assembly 90. The biasing members 124, 134 affect constant engagement of the first primary swing arm 120 and the first secondary swing arm 130 with the respective cams 100 and 102.

Referring now additionally to fig. 6-9, actuation of the primary exhaust latch actuation assembly 110 will be described. Rotation of the exhaust side cam lever 86 causes the cam 100 to engage and thus rotate the first main swing arm 120 about the pivot 126. The biasing member 124 in turn urges the second main swing arm 122 to rotate about the pivot 126. Movement of the second main swing arm 122 moves the latch assembly 60 from the normally engaged position shown in fig. 7 to the disengaged position shown in fig. 9. Further explained, the latch assembly 60 includes an outer pin 140 and an inner pin 142. In the normal engaged position (fig. 7), the outer and inner pins 140, 142 are misaligned with the corresponding first and second main exhaust rocker arms 20a, 20b. In this position, the first and second main exhaust rocker arms 20 and 20b rotate together for simultaneous movement. As the second main swing arm 122 rotates, it translates the outer and inner pins 140, 142 to align with the first and second main exhaust rocker arms 20a, 20b such that only the second main exhaust rocker arm 20b rotates and the first main exhaust rocker arm 20a does not rotate. The return leaf spring 150 urges the latch assembly 60 back to the latched position shown in fig. 9.

Actuation of the secondary exhaust latch actuation assembly 112 will be described. Rotation of the exhaust side cam lever 86 engages the cam 102 and thus rotates the first swing arm 130 about the pivot 136. The biasing member 134 in turn urges the second swing arm 132 to rotate about the pivot 136. Movement of the second swing arm 132 moves the latch assembly 62 from a normally engaged position, such as shown in fig. 7, to a disengaged position, such as shown in fig. 9. Further explained, the latch assembly 62 includes an outer pin 160 and an inner pin 162. The outer pin 160 and the inner pin 162 are misaligned with the corresponding first and second secondary exhaust rocker arms 22a, 22b in a normal engaged position (similar to that shown in fig. 7). In this position, the first and second secondary exhaust rocker arms 22a, 22b rotate together for simultaneous movement. As the second swing arm 132 rotates, it translates the outer pin 160 and the inner pin 162 to align with the first and second secondary exhaust rocker arms 22a, 22b such that only the second secondary exhaust rocker arm 22b rotates and the first secondary exhaust rocker arm 22a does not rotate. The return leaf spring 170 urges the latch assembly 62 back to the latched position similar to that shown in fig. 9.

Referring now to fig. 13-17, the first main exhaust valve rocker arm assembly 20a will be described in greater detail. However, it should be appreciated that the first main intake valve rocker arm assembly 22a is similarly configured with a reset function. The first main exhaust valve rocker arm assembly 20a includes a rocker arm body 180 defining an oil supply passage 182 and an opening 184 that receives the exhaust rocker shaft 48. As will be explained herein, the oil supply passage 182 is aligned with an actuation oil supply passage 190 provided on the exhaust rocker shaft 48 along a first operating condition and with a reset drain passage 192 along a second operating condition. A bushing 196 may be disposed between the rocker arm body 180 and the exhaust rocker shaft 48.

The first main exhaust valve rocker arm assembly 20a may include a cartridge assembly 34 that includes a cartridge housing 212 received in the rocker arm body 180. Cartridge housing 212 defines a plunger chamber 214, a spool chamber 216, and a connection port 218 connecting plunger chamber 214 with spool chamber 216. Cartridge assembly 34 generally includes a plunger assembly 220 and a spool valve assembly 224. Plunger assembly 220 includes plunger 228, plunger biasing member 230, guide bar 232, and pictographic foot 234. Plunger 228 is slidably received in plunger chamber 214 and is biased outwardly by plunger biasing member 230. As will be appreciated, when oil accumulates within plunger chamber 214, plunger 228 is forced outwardly in a rigid position.

Spool valve assembly 224 may generally include an outer body 240, an inner body 242, balls 244, a ball biasing member 246, a spool biasing member 250, a pin 252, and a cover or closure member 256. The outer body 240 and the inner body 242 are collectively referred to herein as spool valve body 260. Spool body 260 may define an upstream spool port 262 and a downstream spool port 264. Spool body 260, balls 244, and ball biasing member 246 may collectively provide spool 270 that selectively allows fluid communication in an open position (as seen in the figure, spool assembly 224 translates to the right) between connecting port 218, upstream spool port 262, and downstream spool port 264.

Turning now to fig. 12 to 17, the operation of the first main exhaust rocker arm 20a having a reset function in the engine braking and driving modes will be described. In the drive mode, spool valve assembly 224 occupies a first position (translated to the left as seen in FIG. 13, biased by spool valve biasing member 250. In the engine braking mode (identified by "FIG. 13" in FIG. 12), spool valve assembly 224 translates to the right and occupies a second position. In the engine braking mode, pressurized oil is communicated through oil supply passage 182 such that spool valve assembly 224 translates to the right and spool valve 270 opens, thereby causing oil to fill spool chamber 214 and move spool 228 to an extended rigid position.

In the drive mode with lost motion (identified in fig. 7 by "fig. 14"), spool valve assembly 224 occupies the first position and plunger chamber 214 is not pressurized. Thus, the plunger 228 is permitted to translate against the bias of the plunger biasing member 230.

The reset function will now be described. As the first main exhaust rocker arm 20a continues to rotate about the rocker shaft 48, the oil supply passage 182 will initially align with the return drain passage 192 (identified in fig. 7 by "fig. 15") allowing oil to drain from the cartridge assembly 210 (left arrow) through the oil supply passage and into the return drain passage 192. Spool valve assembly 224 is translated to the left (identified in fig. 7 by "fig. 17") to avoid biasing of spool valve biasing member 250. Plunger 228 is then free to move to the retracted position (plunger chamber 214 is no longer pressurized). In this regard, the lift profile transitions from a solid line to a dashed line (FIG. 7). After completion of the reset function (identified in FIG. 7 by "FIG. 16"), the spool valve assembly 224 remains biased to the left by the spool valve biasing member 250 and the valve lift may follow the standard exhaust lift profile. For rocker arms configured for engine braking and early exhaust valve opening, an oil control valve will be upstream of the cartridge assembly 210 to control oil flow into the cartridge assembly 210 through the exhaust path 280 in the cartridge housing 212. For early and late intake valve closing, an oil control valve would be connected to the exhaust path 280 downstream, controlling oil flow from the cartridge assembly 210.

Turning now to fig. 4, various operational states of the valve assembly 10 are illustrated. As used herein, the term "enabled" corresponds to the respective latch assembly (60, 62, 64, 66) being in a "first" position that is consistent with simultaneous rotation of the corresponding rocker arm pair. Similarly, the term "deactivated" corresponds to the respective latch assembly being in a "second" position that is consistent with lost motion rotation of the respective second rocker arm relative to the first rocker arm.

For EIVC, the oil feed control valve of the main intake rocker arm assembly 30 is off; the oil drain control valve of the main exhaust rocker arm assembly 20 is opened or closed; the secondary intake rocker arm assembly 32 is deactivated; the secondary exhaust rocker arm assembly 22 is deactivated.

For LIVC, the oil feed control valve of the main intake rocker arm assembly 30 is open; the oil drain control valve of the main exhaust rocker arm assembly 20 is opened or closed; the secondary intake rocker arm assembly 32 is deactivated; the secondary exhaust rocker arm assembly 22 is deactivated.

For standard exhaust lift, the oil feed control valve of the main intake rocker arm assembly 30 is opened or closed; the oil drain control valve of the main exhaust rocker arm assembly 20 is turned off; the secondary intake rocker arm assembly 32 is deactivated; the secondary exhaust rocker arm assembly 22 is deactivated.

For EEVO, the oil feed control valve of the main intake rocker arm assembly 30 is turned on or off; the oil drain control valve of the main exhaust rocker arm assembly 20 is opened; the secondary intake rocker arm assembly 32 is deactivated; the secondary exhaust rocker arm assembly 22 is deactivated.

For TSEB, the main intake rocker arm assembly 30 is deactivated; the main exhaust rocker arm assembly 20 is deactivated; the secondary intake rocker arm assembly 32 is activated; the secondary exhaust rocker arm assembly 22 is activated. During cylinder deactivation, all four rocker arm assemblies 20, 22, 30, and 32 are deactivated.

The foregoing description of the examples has been provided for the purposes of illustration and description. The description is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular example are generally not limited to that particular example, but are interchangeable and can be used for a selected example where applicable, even if not specifically shown or described. The individual elements or features of a particular example may also be varied in a number of ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Claims

1. A cartridge assembly for a rocker arm, comprising:

a cartridge housing including a plunger chamber and a spool chamber;

a plunger assembly comprising a plunger configured to selectively translate within the plunger chamber between an extended rigid position and a retracted non-rigid position;

a spool valve assembly configured to move between a first position and a second position, the spool valve assembly comprising a spool valve configured to selectively move between a closed position configured to maintain pressure in the plunger chamber and an open position configured to pressure flow into the plunger chamber;

a connection port fluidly connecting the plunger chamber and the spool chamber when the spool valve assembly is in the second position; and

a vent path fluidly connecting the plunger chamber and the spool chamber when the spool valve assembly is in the first position, the vent path being separate from the connection port and configured to release pressure from the plunger chamber.

2. The cartridge assembly of claim 1, comprising a plunger biasing member in the plunger chamber configured to bias the plunger outwardly from the plunger chamber.

3. The cartridge assembly of claim 1, wherein the spool valve assembly is configured to translate in the spool valve chamber, wherein the plunger assembly is configured to translate in the plunger chamber, and wherein the plunger assembly translates transverse to the spool valve assembly.

4. A cartridge assembly according to any one of claims 1 to 3, wherein the plunger assembly comprises a spool valve body biased to a closed position.

5. The cartridge assembly of claim 4, wherein the plunger assembly comprises an inner body in an outer body, wherein the inner body is biased to a closed position by a spool valve biasing member.

6. The cartridge assembly of claim 5, comprising a ball biased against the outer body by a ball biasing member seated against the inner body.

7. The cartridge assembly of claim 4, wherein the spool body comprises an upstream spool port and a downstream spool port.

8. The cartridge assembly of claim 7, wherein the spool valve assembly is configured to selectively fluidly connect the connection port to the downstream spool valve port.

9. A rocker arm assembly, comprising:

a rocker arm body including an oil supply passage; and

the cartridge assembly of any one of the preceding claims;

wherein the oil supply passage is fluidly connected to the spool valve chamber.

10. The rocker arm assembly of claim 9 further comprising a pin seated on the rocker arm body and seated against the spool valve assembly.

11. A valve assembly comprising the rocker arm assembly of claim 9, and further comprising a rocker shaft passing through the rocker arm body, the rocker shaft comprising an actuation oil supply passage, wherein the spool valve assembly is configured to move to a second position when the oil supply passage of the rocker arm body is aligned with the actuation oil supply passage on the rocker shaft.

12. The valve assembly of claim 11, wherein the rocker shaft further comprises a reset drain passage, wherein the spool valve assembly is configured to move to a first position when the oil supply passage of the rocker body is aligned with the reset drain passage on the rocker shaft.