CROSS-REFERENCE TO RELATED APPLICATIONS
FIELD
[0002] The present disclosure relates generally to a rocker arm assembly for use in a valve
train assembly and more particularly to a rocker arm assembly that incorporates a
dedicated rocker arm that acts on a single exhaust valve to perform an engine brake
function.
[0003] CN203097985U shows an engine braking device with special cam for braking single valve.
WO2012078280A1 shows engine braking devices and methods.
WO2012162616A1 shows a primary and auxiliary rocker arm assembly for engine valve actuation.
[0004] Compression engine brakes can be used as auxiliary brakes, in addition to wheel brakes,
on relatively large vehicles, for example trucks, powered by heavy or medium duty
diesel engines. A compression engine braking system is arranged, when activated, to
provide an additional opening of an engine cylinder's exhaust valve when the piston
in that cylinder is near a top-dead-center position of its compression stroke so that
compressed air can be released through the exhaust valve. This causes the engine to
function as a power consuming air compressor which slows the vehicle.
[0005] In a typical valve train assembly used with a compression engine brake, the exhaust
valve is actuated by a rocker arm which engages the exhaust valve by means of a valve
bridge. The rocker arm rocks in response to a cam on a rotating cam shaft and presses
down on the valve bridge which itself presses down on the exhaust valve to open it.
A hydraulic lash adjuster may also be provided in the valve train assembly to remove
any lash or gap that develops between the components in the valve train assembly.
[0006] 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.
SUMMARY
[0007] The invention is defined according to the claims.
[0008] A dual exhaust rocker arm assembly constructed in accordance to one example of the
present disclosure is operable in a combustion engine mode and an engine braking mode.
The dual exhaust valve rocker arm assembly selectively opens first and second exhaust
valves and includes a rocker shaft, an exhaust valve rocker arm assembly, an engine
brake rocker arm assembly and an engine brake capsule. The exhaust valve rocker arm
assembly has an exhaust rocker arm that receives the rocker shaft and is configured
to rotate around the rocker shaft. The exhaust rocker arm further defines a bore having
an inner diameter. The engine brake rocker arm assembly has an engine brake rocker
arm. The engine brake capsule is slidably received along the inner diameter of the
bore of the exhaust valve rocker arm. The engine brake capsule is selectively translatable
upon urging by the engine brake rocker arm. The engine brake capsule, in turn, urges
one of the first and second exhaust valves open during engine braking mode.
[0009] According to additional features the dual exhaust valve rocker arm assembly further
comprises an oil control valve that provides oil flow for actuation of the engine
brake capsule from a pressurized oil supply. The engine brake capsule includes an
engine brake capsule piston and an engine brake capsule body. A pressurized oil chamber
is defined between the engine brake capsule piston and the engine brake capsule body.
The engine brake rocker arm is configured to act on the engine brake capsule piston
which acts on the engine brake capsule body which ultimately acts on one of the engine
brake exhaust valves.
[0010] According to other features, the dual exhaust valve rocker arm assembly further comprises
a valve tip positioned between one of the engine brake exhaust valves and the engine
brake capsule body. A lock ball assembly can include a ball lock and a ball lock spring.
The ball lock spring can urge the ball lock into a groove defined on the engine brake
capsule body. A c-clip can be configured on the rocker arm assembly. The c-clip can
limit a stroke of the engine brake capsule and provide a hard stop.
[0011] According to still additional features, the dual exhaust rocker arm assembly further
includes an actuator assembly configured to move the engine brake capsule between
an extended and a retracted position. The actuator assembly and the oil control valve
are configured in the exhaust rocker arm separate from the engine brake capsule. The
actuator assembly includes an actuator body, an actuator check ball, an actuator needle,
an actuator return spring and an actuator locking nut. The actuator needle is configured
to keep the actuator check ball in an open position and prevent oil pressure buildup
in the engine brake capsule. The actuator check ball allows one-way replenishment
at every cycle into the pressurized oil chamber. In engine braking mode, the oil control
valve is energized open and oil pressure causes the actuator needle to move away from
a corresponding seat such that the engine brake capsule is extended a predetermined
length. De-energizing the oil control valve causes the actuator needle to allow oil
out from the pressurized oil chamber and the engine brake capsule to move to the retracted
position allowing combustion. In additional features, the dual exhaust rocker arm
assembly includes a first adjustment screw provided on the engine brake rocker arm
and a second adjustment screw provided on the exhaust rocker arm. Both of the first
and second adjustment screws are adjustable to selectively provide lash settings for
the dual exhaust rocker arm assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The present disclosure will become more fully understood from the detailed description
and the accompanying drawings, wherein:
FIG. 1 is a top view of a partial valve train assembly incorporating a rocker arm
assembly including an intake rocker arm, an exhaust rocker arm and an engine brake
rocker arm constructed in accordance to one example of the present disclosure;
FIG. 2 is a side view of an exhaust rocker arm and an engine brake rocker arm of the
valve train assembly of FIG. 1;
FIG. 3 is a schematic illustration of the exhaust rocker arm and the engine brake
rocker arm of FIG. 2 according to one example;
FIG. 4 is a schematic illustration of the exhaust valve rocker arm assembly of FIG.
2 and shown with an engine brake capsule fully extended;
FIG. 5 is a schematic illustration of the exhaust valve rocker arm assembly of FIG.
2 and shown with the engine brake on max lift;
FIG. 6 is a detail cross-sectional view of a ball lock and ball spring that loads
a ball against a groove defined in an outer diameter of a capsule body of the exhaust
valve rocker arm assembly of FIG. 2 according to one example;
FIG. 7 is a side view of the ball engaging the groove on the outer diameter of the
capsule body of FIG. 6;
FIG. 8 is a top perspective view of a first adjustment screw on the engine brake arm,
a second adjustment screw of the exhaust arm and a third adjustment screw of the intake
arm, all provided to provide valve lash set according to one example of the present
disclosure; and
FIG. 9 is a cross-sectional view of the exhaust rocker arm assembly of FIG. 2 showing
a stroke length of a fully collapsed and fully expanded engine brake capsule;
FIG. 10 is a side view of the exhaust valve rocker arm assembly shown with the exhaust
rocker arm and the engine brake rocker arm on the base circle of the cam shaft;
FIG. 11 is a schematic illustration of the exhaust valve rocker arm assembly of FIG.
10;
FIG. 12 is a side view of the exhaust valve rocker arm assembly shown with the exhaust
rocker arm on maximum lift and the engine brake rocker arm on the base circle of the
cam shaft;
FIG. 13 is a schematic illustration of the exhaust valve rocker arm assembly of FIG.
12;
FIG. 14 is a side view of the exhaust valve rocker arm assembly shown with the exhaust
rocker arm and the engine brake rocker arm on the base circle of the cam shaft;
FIG. 15 is a schematic illustration of the exhaust valve rocker arm assembly of FIG.
14;
FIG. 16 is a side view of the exhaust valve rocker arm assembly shown with the exhaust
rocker arm on the base circle and the engine brake rocker arm rotated a distance counterclockwise
from engaging a raised portion of the cam shaft;
FIG. 17 is a schematic illustration of the exhaust valve rocker arm assembly of FIG.
16;
FIG. 18 is a side view of the exhaust valve rocker arm assembly shown with the exhaust
rocker arm at maximum lift and the engine brake rocker arm on the base circle of the
cam shaft;
FIG. 19 is a schematic illustration of the exhaust valve rocker arm assembly of FIG.
18;
FIG. 20 is a side view of the exhaust valve rocker arm assembly shown with the exhaust
rocker arm and the engine brake rocker arm on the base circle of the cam shaft; and
FIG. 21 is a schematic illustration of the exhaust valve rocker arm assembly of FIG.
20.
DETAILED DESCRIPTION
[0013] Heavy duty (HD) diesel engines with single overhead cam (SOHC) valvetrain requires
high braking power, in particular at low engine speed. The present disclosure provides
an added motion type De-Compression engine brake. To provide high braking power without
applying high load on the rest of the valvetrain (particularly the camshaft), the
present disclosure provides a dedicated rocker arm for engine brake that acts on one
exhaust valve. In this regard, half of the input load is experienced compared to other
configurations that have two exhaust valves opening.
[0014] With initial reference to FIG. 1, a partial valve train assembly constructed in accordance
to one example of the present disclosure is shown and generally identified at reference
10. The partial valve train assembly 10 utilizes engine braking and is shown configured
for use in a three-cylinder bank portion of a six-cylinder engine. It will be appreciated
however that the present teachings are not so limited. In this regard, the present
disclosure may be used in any valve train assembly that utilizes engine braking. The
partial valve train assembly 10 is supported in a valve train carrier 12 and can include
three rocker arms per cylinder.
[0015] Specifically, each cylinder includes an intake valve rocker arm assembly 20, an exhaust
valve rocker arm assembly 22 and an engine brake rocker arm assembly 24. The exhaust
valve rocker arm assembly 22 and the engine brake rocker arm assembly 24 cooperate
to control opening of the exhaust valves and are collectively referred to as a dual
exhaust valve rocker arm assembly 26 (FIG. 2). The intake valve rocker arm assembly
20 is configured to control motion of the intake valves. The exhaust valve rocker
arm assembly 22 is configured to control exhaust valve motion in a drive mode. The
engine brake rocker arm assembly 24 is configured to act on one of the two exhaust
arms in an engine brake mode as will be described herein. A rocker shaft 34 is received
by the valve train carrier 12 and supports rotation of the exhaust valve rocker arm
assembly 22 and the engine brake rocker arm assembly 24.
[0016] With further reference now to FIGS. 2 and 3, an exhaust valve rocker arm assembly
22 will be further described. The exhaust valve rocker arm assembly 22 can generally
include an exhaust rocker arm 40, a valve bridge 42, a spigot spigot assembly 44 and
an engine brake capsule 46. The valve bridge 42 engages a first and second exhaust
valve 50 and 52 (FIG. 2) associated with a cylinder of an engine (not shown). The
exhaust rocker arm 40 rotates around the rocker shaft 34 based on a lift profile of
a cam shaft 54. The engine brake rocker arm assembly 24 can include an engine brake
rocker arm 60 having an engaging portion 62. The engine brake rocker arm 60 rotates
around the rocker shaft 34 based on a lift provide of the cam shaft 54.
[0017] With specific reference to FIG. 3, schematic function of the exhaust valve rocker
arm assembly 22 and the engine brake rocker arm assembly 24 will be described. The
configuration includes an oil control valve 70 that provides oil flow 72 for actuation
from a pressurized oil supply 74. Pressurized oil chamber 78 is shown inside the engine
brake capsule 46. The engine brake capsule 46 can include an engine brake capsule
piston 80 and an engine brake capsule body 82. A valve tip pin 83 is positioned between
the exhaust valve 52 and the engine brake capsule body 82. A c-clip 84 can provide
a hard stop for the engine brake capsule body 82. An engine brake rocker arm schematic
90 represents the engine brake rocker arm assembly 24 rotating as a result of cam
lobe breaking 92.
[0018] An actuator assembly 100 includes an actuator body 102, an actuator check ball 104,
an actuator needle 106, an actuator return spring 108 and an actuator locking nut
110. When the engine is in drive (combustion) mode, the oil control valve 70 is closed
and the engine brake capsule body 82 is completely retracted having no influence on
the exhaust valves 50 and 52 motion. The actuator needle 106 can keep the check ball
104 in an open position (away from corresponding seat 107) and prevent oil pressure
buildup in the engine brake capsule 46. The motion of the engine brake rocker arm
60 (FIG. 2), or represented in FIG. 3 as the rocker arm schematic 90 will have no
effect on the motion of the exhaust valve 52 when the engine is in drive mode.
[0019] When the engine is in brake (no combustion) mode, the oil control valve 70 will be
energized open and oil pressure will push back the actuator needle 106 and fill (extend)
the engine brake capsule 46 for a predetermined length such as 4 mm. A gap between
the engine brake rocker arm 60 (rocker arm schematic 90) and the exhaust valve 52
will be compensated so that motion of the engine brake rocker arm 60 controlled by
the cam lobe 92 will create additional lift on the exhaust valve 52. The actuator
check ball 104 will allow one-way oil replenishment at every cycle into the pressurized
oil chamber 78. When de-energizing the oil control valve 70, the needle 106 will allow
oil out from the pressurized oil chamber 78 and the engine brake capsule 46 will go
back into a retracted position allowing driving mode (combustion) again. The engine
brake rocker arm assembly 24 opens the exhaust valve 52 (positioned closer to the
rocker shaft 34) providing favorable force ratio allowing higher braking power. The
exhaust valve 52 is opened later in a compression stroke (close to top dead center),
still with acceptable load on the cam lobe.
[0020] FIG. 4 illustrates the engine brake capsule 46 expanded or extended. The gap between
the engine brake capsule body 82 and the valve tip pin 83 is eliminated. FIG. 5 illustrates
the engine brake at maximum lift. The exhaust rocker arm 40 is on the base circle
while the engine brake rocker arm 60 controls the lift of the engine brake exhaust
valve 52. Explained further, the engine brake rocker arm 60 acts on the engine brake
capsule piston 80, which acts on the engine brake capsule body 82, which acts on the
valve tip pin 83, which acts on the engine brake exhaust valve 52.
[0021] With reference now to FIGS. 6 and 7, additional features of the present disclosure
will be described. A ball lock assembly 150 includes a ball lock 152 and a ball lock
spring 154. The ball lock spring 154 urges (identified by force F, FIG. 7) the ball
lock 152 into a groove 160 defined on the outer diameter of the engine brake capsule
body 82. The groove 160 has a depth 170 and a radius 172 configured to assure the
engine brake capsule body 82 does not shake by its inertia, but rather under the load
of the engine brake rocker arm 60 in engine brake mode. The ball lock assembly 150
will have no impact on the engine brake capsule piston 80 expansion or retraction
time. A c-clip 180 is provided to limit the stroke of the engine brake capsule body
82. In this regard, the c-clip 180 provides a hard stop important for transportation.
[0022] Turning now to FIGS. 8 and 9, additional features will be described. A first adjustment
screw 210 is provided on the engine brake arm 60. A second adjustment screw 212 is
provided on the exhaust arm 40. A third adjustment screw 214 is provided on the intake
arm 20. Each of the first, second and third adjustment screws 210, 212 and 214 all
provide valve lash settings according to one example of the present disclosure. To
set the engine brake lash, the engine brake capsule 46 is pushed down (as viewed in
FIG. 9) into the collapsed position (no oil) to zero the lash in the exhaust valve
52. From this position, the first adjustment screw 210 is re-winded for exhaust brake
capsule stroke and lash on the same valve. In one example the engine brake capsule
46 is made such that the difference between a fully collapsed and fully expanded length
is within a narrow tolerance 220 (such as plus or minus 0.05 mm). Each of the first,
second and third adjustment screws 210, 212 and 214 can have a common thread and nut
size so that a common tool can be used for adjustment.
[0023] The present configuration provides many benefits. For example, actuation of engine
brake function is controlled by pressurized engine oil by two oil control valves 70,
one for each of the three cylinders (for the example shown in FIG. 1). The oil control
valves 70 can be configured to operate independently. Valve actuation components for
three cylinders are incorporated in one valvetrain carrier 12 ready to be assembled
on a cylinder head. The configuration provides high performance engine braking without
necessarily creating high load on valvetrain components by acting solely on one exhaust
valve 52. By using a dedicated rocker arm (engine brake rocker arm 60), for engine
brake, favorable rocker and force ratio transmitting lower load on the rocker shaft
34 and camshaft 54.
[0024] Furthermore, the engine brake capsule 46 is installed in and guided by an inner diameter
190 (FIG. 6) defined in the exhaust rocker arm 40. In this regard, while prior art
configurations may provide a hydraulic capsule configured within the engine brake
rocker arm, the present disclosure includes an engine brake capsule 46 configured
in the exhaust rocker arm 40 (instead of in the engine brake rocker arm 60). The configuration
provides favorable packaging advantages. The engine brake capsule 46 is configured
to move freely along the inner diameter 190 in the exhaust rocker arm 40 while being
controlled by the engine brake rocker arm 60.
[0025] The configuration of the present disclosure provides actuation control from the actuator
assembly 100 to move the engine brake capsule 46 between an extended and retracted
position. The actuator assembly 100 and the oil control valve 70 (FIG. 3) are configured
in the exhaust rocker arm 40 and are separate from the engine brake capsule 46. Moreover,
the ball lock assembly 150 provides drive mode retention of the engine brake capsule
body 82 in drive mode.
[0026] With reference now to FIGS. 10-21, an exemplary operating sequence of the dual exhaust
valve rocker arm assembly 26 will be described. FIG. 10 shows the exhaust rocker arm
40 and the engine brake rocker arm 60 on the base circle of the cam shaft 54. The
engaging portion 62 of the engine brake engine brake rocker arm 60 is disengaged with
the engine brake capsule piston 80. The engine brake capsule 46 is collapsed. The
schematic of FIG. 11 corresponds to the position of the dual exhaust valve rocker
arm assembly 26 in FIG. 10. The oil control valve 70 is closed draining open. The
check ball 104 is in an open position away from its seat 107.
[0027] FIGS. 12 and 13 will now be described. FIG. 12 shows the exhaust rocker arm 40 on
maximum lift of the cam shaft 54 and the engine brake rocker arm 60 on the base circle
of the cam shaft 54. The engaging portion 62 of the engine brake rocker arm 60 is
disengaged with the engine brake capsule piston 80. An exhaust brake rocker arm lost
motion spring 232 keeps the engine brake rocker arm 60 against the camshaft 54. The
engine brake capsule 46 is collapsed. The schematic of FIG. 13 corresponds to the
position of the dual exhaust valve rocker arm assembly 26 in FIG. 12. The oil control
valve 70 is closed draining open. The check ball 104 is in an open position away from
its seat 107.
[0028] FIGS. 14 and 15 will now be described. FIG. 14 shows the exhaust rocker arm 40 on
the base circle of the cam shaft 54 and the engine brake rocker arm 60 on the base
circle of the cam shaft 54. The engaging portion 62 of the engine brake rocker arm
60 is engaged with the engine brake capsule piston 80. The engine brake capsule 46
is expanded such that engine brake capsule body 82 touches the valve tip 83 on the
valve bridge 42. The schematic of FIG. 15 corresponds to the position of the dual
exhaust valve rocker arm assembly 26 in FIG. 14. The oil control valve 70 is open.
The needle 106 is retracted. The check ball 104 opens only under oil pressure from
the oil control valve 70.
[0029] FIGS. 16 and 17 will now be described. FIG. 16 shows the exhaust rocker arm 40 on
the base circle of the cam shaft 54 and the engine brake rocker arm 60 rotated a distance
counterclockwise from engaging a raised portion of the cam shaft 54. The engaging
portion 62 of the engine brake rocker arm 60 is engaged with the engine brake capsule
piston 80. The engine brake capsule 46 is expanded such that engine brake capsule
body 82 touches the valve tip 83 on the valve bridge 42. Rigid transitioning of the
engine brake rocker arm 60 motion to the exhaust valve 52 engine brake lift (opening)
is shown. The schematic of FIG. 17 corresponds to the position of the dual exhaust
valve rocker arm assembly 26 in FIG. 16. The oil control valve 70 is open. The needle
106 is retracted. The check ball 104 is closed by pressure from the engine brake capsule
46.
[0030] FIGS. 18 and 19 will now be described. FIG. 18 shows the exhaust rocker arm 40 at
maximum lift on cam shaft 54 and the engine brake rocker arm 60 on the base circle
of the cam shaft 54. Once passed the engine brake lift, the exhaust rocker arm assembly
22 will control opening of both valves 50, 52. The engine brake rocker arm 60 will
be kept in place against the cam shaft 54 by the lost motion spring 232. The schematic
of FIG. 19 corresponds to the position of the dual exhaust valve rocker arm assembly
26 in FIG. 18. The oil control valve 70 is open. The needle 106 is retracted. The
check ball 104 opens only by pressure from the engine brake capsule 46. The engine
brake capsule 46 will expand up to its hard stop for maximum extension.
[0031] FIGS. 20 and 21 will now be described. FIG. 20 shows the exhaust rocker arm 40 and
the engine brake rocker arm 60 on the base circle of the cam shaft 54. Both exhaust
valves 50, 52 will close contemporary controlled by the exhaust rocker arm assembly
22. The engine brake capsule 46 will be (again) fully expanded. Oil leaked out from
the engine brake capsule 46 during the lift will be replenished. The schematic of
FIG. 21 corresponds to the position of the dual exhaust valve rocker arm assembly
26 in FIG. 20. The oil control valve 70 is open. The needle 106 is retracted. The
check ball 104 opens only by pressure from the engine brake capsule 46. The engine
brake capsule 46 will expand up to its hard stop for maximum extension.
1. A dual exhaust valve rocker arm assembly (26) operable in a combustion engine mode
and an engine braking mode, the dual exhaust valve rocker arm assembly (26) selectively
opening first and second exhaust valves (50, 52) and comprising:
a rocker shaft (34);
an exhaust valve rocker arm assembly (22) having an exhaust rocker arm (40) that receives
the rocker shaft (34) and is configured to rotate around the rocker shaft (34), the
exhaust rocker arm further (40) defining a bore having an inner diameter (190);
an engine brake rocker arm assembly (24) having an engine brake rocker arm (60); and
an engine brake capsule (46) slidably received along the inner diameter (190) of the
bore of the exhaust valve rocker arm (40), wherein the engine brake capsule (46) includes
an engine brake capsule piston (80) and an engine brake capsule body (82), wherein
a pressurized oil chamber (78) is defined between the engine brake capsule piston
(80) and the engine brake capsule body (82), wherein the engine brake rocker arm (60)
is configured to act on the engine brake capsule piston (80) which acts on the engine
brake capsule body (82) which ultimately acts on one of the first and second exhaust
valves (50, 52), and wherein the engine brake capsule (46) is selectively translatable
upon urging by the engine brake rocker arm- (60), the engine brake capsule (46), in
turn, urging one of the first and second exhaust valves (50, 52) open during engine
braking mode;
wherein the dual exhaust valve rocker arm assembly further comprises:
an oil control valve (70) that provides oil flow for actuation of the engine brake
capsule (46) from a pressurized oil supply (74),
characterized in that:
the dual exhaust valve rocker arm assembly (26) comprises:
a lock ball assembly (150) including a ball lock (152) and a ball lock spring (154);
wherein the ball lock spring (154) of the lock ball assembly (150) is configured to
urge the ball lock (152) into a groove (160) defined on the engine brake capsule body
(82) to provide retention of the engine brake capsule body (82) in the combustion
mode;
wherein, when the engine is in the combustion mode, the oil control valve (70) is
closed and the engine brake capsule body (82) is completely retracted having no influence
on the first and second exhaust valves (50, 52) motion and is retained by the lock
ball assembly (150).
2. The dual exhaust valve rocker arm assembly of claim 1, further comprising a valve
tip (83) positioned between one of the first and second exhaust valves (52) and the
engine brake capsule body (82).
3. The dual exhaust valve rocker arm assembly of claim 1, further comprising a c-clip
(84) configured on the rocker arm assembly and that limits a stroke of the engine
brake capsule (46) and provides a hard stop.
4. The dual exhaust valve rocker arm assembly of claim 1, further comprising:
an actuator assembly configured to move the engine brake capsule (46) between an extended
and a retracted position.
5. The dual exhaust valve rocker arm assembly of claim 4, wherein the actuator assembly
(100) and the oil control valve (70) are configured in the exhaust rocker arm (40)
separate from the engine brake capsule (46).
6. The dual exhaust valve rocker arm assembly of claim 4, wherein the actuator assembly
(100) includes an actuator body (102), an actuator check ball (140), an actuator needle
(106), an actuator return spring (108) and an actuator locking nut (110), wherein
the actuator needle (106) is configured to keep the actuator check ball (140) in an
open position and prevent oil pressure build-up in the engine brake capsule (46).
7. The dual exhaust valve rocker arm assembly of claim 6, wherein the actuator check
ball allows (140) one-way replenishment at every cycle into the pressurized oil chamber
(78).
8. The dual exhaust valve rocker arm assembly of claim 6, wherein in engine braking mode,
the oil control valve (70) is energized open and oil pressure causes the actuator
needle (106) to move away from a corresponding seat (107) such that the engine brake
capsule (46) is extended a predetermined length.
9. The dual exhaust valve rocker arm assembly of claim 8, wherein de-energizing the oil
control valve (70) causes the actuator needle (106) to allow oil out from the pressurized
oil chamber (78) and the engine brake capsule (46) to move to the retracted position
allowing combustion.
10. The dual exhaust valve rocker arm assembly of claim 1, further comprising:
a first adjustment screw provided (210) on the engine brake rocker arm (60); and
a second adjustment screw (212) provided on the exhaust rocker arm (40); wherein both
of the first and second adjustment screws (210, 212) are adjustably positioned to
selectively provide lash settings for the dual exhaust rocker arm assembly.
1. Doppelauslassventil-Kipphebelarmanordnung (26), die in einem Verbrennungsmotormodus
und einem Motorbremsmodus betreibbar ist, wobei die Doppelauslassventil-Kipphebelanordnung
(26) selektiv erste und zweite Auslassventile (50, 52) öffnet, und Folgendes umfasst:
eine Kipphebelwelle (34);
eine Auslassventil-Kipphebelarmanordnung (22), die einen Auslasskipphebelarm (40)
aufweist, der die Kipphebelwelle (34) aufnimmt und konfiguriert ist, um sich um die
Kipphebelwelle (34) herum zu drehen, wobei der Auslasskipphebelarm (40) eine Bohrung
definiert, die einen Innendurchmesser (190) aufweist;
eine Motorbremskipphebelarmanordnung (24), die einen Motorbremskipphebelarm (60) aufweist;
und
eine Motorbremskapsel (46), die gleitend entlang des Innendurchmessers (190) der Bohrung
des Auslasskipphebelarms (40) aufgenommen ist, wobei die Motorbremskapsel (46) einen
Motorbremskapselkolben (80) und einen Motorbremskapselkörper (82) beinhaltet, wobei
eine mit Druck beaufschlagte Ölkammer (78) zwischen dem Motorbremskapselkolben (80)
und dem Motorbremskapselkörper (82) definiert ist, wobei der Motorbremskipphebelarm
(60) konfiguriert ist, um auf den Motorbremskapselkolben (80) zu wirken, der auf den
Motorbremskapselkörper (82) wirkt, der schließlich auf eines von dem ersten und zweiten
Auslassventil (50, 52) wirkt, und wobei die Motorbremskapsel (46) beim Forcieren durch
den Motorbremskipphebelarm (60) verschiebbar ist, wobei die Motorbremskapsel (46)
wiederum während des Motorbremsmodus eines von dem ersten und zweiten Auslassventil
(50, 52) zwangsöffnet;
wobei die Doppelauslassventil-Kipphebelarmanordnung weiter umfasst:
ein Ölsteuerventil (70), das einen Ölfluss zum Betätigen der Motorbremskapsel (46)
aus einer mit Druck beaufschlagten Ölzuführung (74) bereitstellt,
dadurch gekennzeichnet, dass:
die Doppelauslassventil-Kipphebelarmanordnung (26) umfasst:
eine Verriegelungskugelanordnung (150), die eine Kugelverriegelung (152) und eine
Kugelverriegelungsfeder (154) beinhaltet;
wobei die Kugelverriegelungsfeder (154) der Verriegelungskugelanordnung (150) konfiguriert
ist, um die Kugelverriegelung (152) in eine Nut (160) zu forcieren, die auf dem Motorbremskapselkörper
(82) definiert ist, um eine Bewahrung des Motorbremskapselkörpers (82) im Verbrennungsmodus
bereitzustellen;
wobei, wenn der Motor im Verbrennungsmodus ist, das Ölsteuerventil (70) geschlossen
ist, und der Motorbremskapselkörper (82) vollständig eingezogen ist, keinen Einfluss
auf die Bewegung des ersten und zweiten Auslassventils (50, 52) aufweist und durch
die Verriegelungskugelanordnung (150) zurückgehalten wird.
2. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 1, weiter eine Ventilspitze
(83) umfassend, die zwischen einem von dem ersten und zweiten Auslassventil (52) und
dem Motorbremskapselkörper (82) positioniert ist.
3. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 1, weiter einen C-Clip (84)
umfassend, der auf der Kipphebelarmanordnung konfiguriert ist und einen Hub der Motorbremskapsel
(46) eingrenzt und einen harten Stopp bereitstellt.
4. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 1, weiter umfassend:
eine Betätigeranordnung, die konfiguriert ist, um die Motorbremskapsel (46) zwischen
einer ausgefahrenen und eingezogenen Position zu bewegen.
5. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 4, wobei die Betätigeranordnung
(100) und das Ölsteuerventil (70) in dem Auslasskipphebelarm (40) von der Motorbremskapsel
(46) getrennt konfiguriert sind.
6. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 4, wobei die Betätigeranordnung
(100) einen Betätigerkörper (102), eine Betätigersperrkugel (140), eine Betätigernadel
(106), eine Betätigerrückstellfeder (108) und eine Betätigerverriegelungsmutter (110)
beinhaltet, wobei die Betätigernadel (106) konfiguriert ist, um die Betätigersperrkugel
(140) in einer offenen Position zu halten, und zu verhindern, dass der Öldruck in
der Motorbremskapsel (46) ansteigt.
7. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 6, wobei die Betätigersperrkugel
(140) eine Einweg-Auffüllung in jedem Zyklus in die mit Druck beaufschlagte Ölkammer
(78) erlaubt.
8. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 6, wobei das Ölsteuerventil
(70) im Motorbremsmodus stromversorgt offen ist und der Öldruck dafür sorgt, dass
sich die Betätigernadel (106) von einem entsprechenden Sitz (107) wegbewegt, sodass
die Motorbremskapsel (46) um eine vorbestimmte Länge erweitert wird.
9. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 8, wobei das Stromlosmachen
des Ölsteuerventils (70) dafür sorgt, dass die Betätigernadel (106) Öl aus der mit
Druck beaufschlagten Ölkammer (78) herauslässt, und sich die Motorbremskapsel (46)
in die eingezogene Position bewegt, um eine Verbrennung zu erlauben.
10. Doppelauslassventil-Kipphebelarmanordnung nach Anspruch 1, weiter umfassend:
eine erste Einstellschraube (210), die auf dem Motorbremskipphebelarm (60) bereitgestellt
ist; und
eine zweite Einstellschraube (212), die auf dem Auslasskipphebelarm (40) bereitgestellt
ist; wobei beide der ersten und zweiten Einstellschraube (210, 212) einstellbar positioniert
sind, um selektiv Spieleinstellungen für die Doppelauslassventil-Kipphebelarmanordnung
bereitzustellen.
1. Ensemble culbuteur à double échappement (26) pouvant fonctionner dans un mode moteur
à combustion et un mode frein moteur, l'ensemble culbuteur à double échappement (26)
ouvrant de façon sélective des première et seconde soupapes d'échappement (50, 52)
et comprenant :
un axe de culbuteur (34) ;
un ensemble culbuteur à soupape d'échappement (22) ayant un culbuteur d'échappement
(40) qui reçoit l'axe de culbuteur (34) et est configuré pour tourner autour de l'axe
de culbuteur (34), le culbuteur d'échappement (40) définissant en outre un alésage
ayant un diamètre interne (190) ;
un ensemble culbuteur de frein moteur (24) ayant un culbuteur de frein moteur (60)
; et
une capsule de frein moteur (46) reçue de manière coulissante le long du diamètre
interne (190) de l'alésage du culbuteur d'échappement (40), dans lequel la capsule
de frein moteur (46) comprend un piston de capsule de frein moteur (80) et un corps
de capsule de frein moteur (82), dans lequel une chambre d'huile sous pression (78)
est définie entre le piston de capsule de frein moteur (80) et le corps de capsule
de frein moteur (82), dans lequel le culbuteur de frein moteur (60) est configuré
pour agir sur le piston de capsule de frein moteur (80) qui agit sur le corps de capsule
de frein moteur (82) qui enfin agit sur l'une des première et seconde soupapes d'échappement
(50, 52), et dans lequel la capsule de frein moteur (46) se déplace en translation
de façon sélective lors de la poussée par le culbuteur de frein moteur (60), la capsule
de frein moteur (46), à son tour, poussant l'ouverture de l'une des première et seconde
soupapes d'échappement (50, 52) en mode frein moteur ;
dans lequel l'ensemble culbuteur à double échappement comprend en outre :
une soupape de commande d'huile (70) qui fournit un flux d'huile pour l'actionnement
de la capsule de frein moteur (46) depuis une alimentation en huile sous pression
(74),
caractérisé en ce que :
l'ensemble culbuteur à double échappement (26) comprend :
un ensemble bille de verrouillage (150) comprend un verrouillage à billes (152) et
un ressort de verrouillage à billes (154) ;
dans lequel le ressort de verrouillage à billes (154) de l'ensemble bille de verrouillage
(150) est configuré pour pousser le verrouillage à billes (152) dans une rainure (160)
définie sur le corps de capsule de frein moteur (82) pour fournir la rétention du
corps de capsule de frein moteur (82) en mode combustion ;
dans lequel, lorsque le moteur est en mode combustion, la soupape de commande d'huile
(70) est fermée et le corps de capsule de frein moteur (82) est complètement rétracté
et n'a aucune influence sur le mouvement des première et seconde soupapes d'échappement
(50, 52) et est retenu par l'ensemble bille de verrouillage (150).
2. Ensemble culbuteur à double échappement selon la revendication 1, comprenant en outre
une pointe de soupape (83) positionnée entre l'une des première et seconde soupapes
d'échappement (52) et le corps de capsule de frein moteur (82).
3. Ensemble culbuteur à double échappement selon la revendication 1, comprenant en outre
un clip en c (84) configuré sur l'ensemble culbuteur et qui limite une course de la
capsule de frein moteur (46) et fournit une butée dure.
4. Ensemble culbuteur à double échappement selon la revendication 1, comprenant en outre
:
un ensemble actionneur configuré pour déplacer la capsule de frein moteur (46) entre
une position étendue et une position rétractée.
5. Ensemble culbuteur à double échappement selon la revendication 4, dans lequel l'ensemble
actionneur (100) et la soupape de commande d'huile (70) sont configurés dans le culbuteur
d'échappement (40) à distance de la capsule de frein moteur (46).
6. Ensemble culbuteur à double échappement selon la revendication 4, dans lequel l'ensemble
actionneur (100) comprend un corps d'actionneur (102), une bille de retenue d'actionneur
(140), une aiguille d'actionneur (106), un ressort de rappel d'actionneur (108) et
un écrou de verrouillage d'actionneur (110), dans lequel l'aiguille d'actionneur (106)
est configurée pour maintenir la bille de retenue d'actionneur (140) dans une position
ouverte et empêche l'accumulation de pression d'huile dans la capsule de frein moteur
(46).
7. Ensemble culbuteur à double échappement selon la revendication 6, dans lequel la bille
de retenue d'actionneur (140) permet un réapprovisionnement unidirectionnel à chaque
cycle dans la chambre d'huile sous pression (78).
8. Ensemble culbuteur à double échappement selon la revendication 6, dans lequel en mode
frein moteur, la soupape de commande d'huile (70) est activée en ouverture et la pression
d'huile amène l'aiguille d'actionneur (106) à s'éloigner d'un siège correspondant
(107) de telle sorte que la capsule de frein moteur (46) est étendue d'une longueur
prédéterminée.
9. Ensemble culbuteur à double échappement selon la revendication 8, dans lequel la désactivation
de la soupape de commande d'huile (70) amène l'aiguille d'actionneur (106) à laisser
l'huile sortir de la chambre d'huile sous pression (78) et la capsule de frein moteur
(46) à se déplacer vers la position rétractée, permettant la combustion.
10. Ensemble culbuteur à double échappement selon la revendication 1, comprenant en outre
:
une première vis de réglage (210) prévue sur le culbuteur de frein moteur (60) ; et
une seconde vis de réglage (212) prévue sur le culbuteur d'échappement (40) ; dans
lequel les première et seconde vis de réglage (210, 212) sont positionnées de manière
réglable pour fournir de façon sélective des réglages de jeu pour l'ensemble culbuteur
à double échappement.