Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to pressure responsive valves
and more particularly to a pressure responsive valve suitable
for simultaneously controlling several fluid flow paths.
Various functions of internal combustion engines are
controlled by devices relying on vacuum pressure established
adjacent the intake manifold of the engine. Such pressure varies
from a negative or a vacuum pressure to 2ero pressure and has a
relationship to the loading of the engine. However, with tùrbo-
charged engines, manifold pressure varies from a negative to
a positive pressure and the vacuum signals originating from
the carburetor do not accurately reflect engine load. For
proper engine operations certain functions of the engine should
be terminated when under loading conditions which in conVen~
tional engines would result in low vacuum pressure, Examples~
of such ~unctions are vacuum advance at the distributor, ex-
haust gas recirculation control and air cleaner temperature
control.
The invention provides a control mechanism for turbo-
charged internal combustion engines having a control device
responslve to intake manifold vacuum pressure and having a
housing including a first member forming a valve cavity and
a second member forming inlet r outlet and exhaust ports, the
inlet port communicating with a variable s~urce of vacuum,
the outlet porc communicating with the control device and the
exhaust port communicating with the exterior of the housing,
valve means including a valve element disposed in the valve
cavity and being movable between the normal open position in
which the lnlet and outlet ports communicate with each other
to an operative position in which the inlet port is closed and
the outlet port communicates through passage means in the
second member with the exhaust port and the control de~ice,
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a movable wall and a third member holding the movable wall
relative to the second chamber and forming a control chamber
at one side of the movable wall, the other side of the movable-
wall being connected to said valve element, a control port
connected to said control member and being connected to said
engine manifold, spring means biasing said movable wall to
a first position to maintain the valve element in its normal
open position in the presence of a pressure in the control cham- ~
ber no greater than atmospheric pressure, the movable wall be- -
ing movable to a second position in the presence of a positive
pressure greater than atmospheric pressure to movè the valve
element to the operative position to isolate the control device.
Figure 1 is a schematic view of an air~fuel induction
system and control devices used with a turbo charged engine un~
der the control of the valve mechanism embodying the invention;
Figure 2 is a cross-sectiona]. elevation of the con-
trol mechanism seen in Figure 1 but at an enlaryed scale;
Figure 3 is an end view of the control`mechanism
seen in Figure 2; and
Figure 4 is a cross-sectional view of a portion of
the control mechanism seen in Figure 3 and taken on line 4-4.
The present invention is embodied in a valve 10 for
use with an induction system indicated at 12 for a turbo-
charged engine. The induction system 12 includes a carburetor
14 having an induction passage 16 under the control of a throt-
tle valve 20. Disposed in the induction passage is a turbo-
charger compressor 22 which receives the air charge from the
inductlon passage 16 and delivers it to the intake manifold 24
of the engine.
The control valve 10 of the present invention is
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connected to an outlet 28 associated with the intake manifold
and is employed for the purpose of controlling various vacuum
operated functions indicated at 30, 32 and 34 and connected
through the valve 10 to the intake manifold 24,
The control valve 10 includes a housing 40 having a
pair of housing members 42 and 44 made of plastic material or
the like and forming a plurality of valve chambers of cavities
46. The housing members 42 and 44 are held in abutting rela-
tionship with each other by a metal shell member 48. The
valve housing is small in size and in actual practice has a
diameter of less than two inches, The shell membèr 48 and
housing member 44 form a housing cavity which is divided into
an operating chamber 50 and an exhaust chamber 52 by a dia~
phragm assembly 54. The diaphragm assembly 54 has a diaphragm
56 with the outer peripheral edge 58 clamped to the housing
member 44.
The housing member 42 is provided with a plurality
of annularly spaced ports 61, 62, 63, 64, 65 and 66 and a cen-
ter port 67 all communicating with the interior of the housing
' 40. Each of the ports is in form of a tapered stem to receive
a hose or conduit for conveying air. ~djoining pairs of ports
communicate with each other. For example, port 61 communicates
with port 62, port 63 communicates with port 64 and port 65
communicates with port 66, Each pair of ports has a passage-
way 69 formed in the housing member 44 by which the ports ofeach pair communicate with each other,
One valve cavity 46 is associated with each pair of
control ports and contains a valve assembly 74, Each valve
assembly includes a valve closure element or disc 76 one side
of which is adapted to seat on an O~ring and the other side
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of which ls adapted to seat on an O~ring 80, One O~ring 80
surrounds each of the inlet ports 61, 63 and 65, Each of
the O-rings 78 is seated in a cavity 46 around a valve stem 82
formed integrally wi-th each of the discs 76. The valve s-tem
82 is slidably supported in an opening 84 formed in the housing
member 44. The wall of opening 84 is formed with a groove 86
by which the valve cavities 46 communicates with the exhaust
chamber 52 at one side of the diaphragm assembly 54,
The ends of the valve stem 82 opposite to the valve
discs 76 are attached to the diaphragm assembly 54 which in-
cludes a backing plate 88 and a backing plate 90 held -together
at opposite surfaces of the diaphragm 56 by means of a central
stem 92 formed integrally with the backing plate 88 and passing
through an opening in the backing plate 90 and upset as indi-
cated at 93 to rivet the backing plates ~8 and 90 together,
The backing plate 90 is provided with a plurality of cavities
94 which receive the heads 95 on each of the valve stems 82 so
that movement of the diaphragm assembly 54 results in movement
of the stems 82. The diaphragm assembly 54 is biased to the
left as viewed in the drawings by a spring 96 which is disposedaxially of the housing 40 in a bore 98 so that the parts norm~
ally occupy the positions seen in Figure 3 with all of the
valve discs 76 in contact with the O-rings 78. T'ne bore 98
. maintains the associated exhaust chamber 52 in communication
with the port 67 and therefore the a-tmosphere.
The shell 48 of the housing 40 supports an elongated
intake member 100 communicating with the operating chamber 50
at the interior of the housing 40 and is adapted to be connec-
ted to the intake maniold 24 of the induction system 12.
In the normal condition of the valve 10, the spring
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96 biases the diaphragm assembly 54 to the left so that the
valve discs 76 are all seated on the O-rings 78. Under such
conditions the inlet ports 61, 63, and 65 of each pair of ports
communicates with the outlet ports 62, 64 and 66 respectively.
Similarly, when the control chamber 50 is subjected to vacuum
pressure, the exhaust chamber 52 at the opposite side of the
diaphragm 56 will be subjected to atmospheric pressure by way
of the center port 67 and bore 98. This results in a differ-
ential pressure urging the diaphragm assembly 54 to the left.
Such movement pulls on the valve stems 82 to pull the valve
discs 76 to the left into sealing engagement with the O-rings
78. This closes off communication between the valve cavities
46 and the exhaust port 67 but maintians the pairs of inlet and
outlet ports in communication with each other and permits air
flow in the fluid flow lines or paths between the manifold and
devices 30, 32 and 34.
Under certain conditions of engine loading, the pres-
sure in the intake manifold will increase above the typical
vacuum pressure. By way of example, such pressure may be in
the range of one to two psi. When the pressure reaches such
levels in the control chamber 50 a differential is created on
the diaphragm 56 which acts to the right as viewed in the draw-
ings. The pressure differential causes movement of diaphragm
assembly 54 to compress the spring 96 and to simultaneously
move all of the valve stems 82 and the attached discs 76 to
the right out of engagement with the seats formed by the O-rings
78.
When the valve discs 76 move out of engagement with
the O-rings 78 and into engagement with the O-rings 80, the
inlet ports 61, 63 and 65 from the vacuum source, namely the
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intake m~nifold 24, are closed so that they are isolated from
the outlet ports 62, 64 and 66. Simultaneously, the outlet
ports 62, 64 and 66 are opened to the center exhaust port 67 by
way of the passageways 6~, valve cavities 46, groove 86 and
exhaust chamber 52, Such communication assures that any resi-
dual pressure, that is, vacuum pressure existing in the con-
trolled devices 30, 32 and 34 is disipated to bring the pres-
sure to atmospheric pressure threby terminating further opera-
tion of the devices 30, 32 and 34,
When the manifold pressure returns to a vacuum level,
the differential pressure acting on the diaphragm 56 and the
biasing effort of the spring 96 moves the diaphragm assembly 54
and valve discs 76 to the left as viewed in the drawings so
that the valve discs 76 are reseated on the O-rings 78. Under
those conditions the exhaust passageways are closed to the
valve cavities 46 and the pairs of inl.et and outlet ports are
placed in communication with each other so that control func-
tions at the control devices 30, 32 and 34 can resume.
Although the valve control mechanism has been dis-
closed with three fluid flow paths, it will be understood thata lesser or greater number of such paths could be used.
A valve control mechanism for a turbo-charged inter-
nal combustion engine has been provided for regulating a plura-
lity of control devices used to regulate the engine and which
are responsive to the pressure in the air-fuel induction system
of the engine. A control mechanism is responsive to the pres-
sure in the air~fuel induction system to move a plurality of
valves simultaneously between an open position in which the
various control devices are free to respond to the pressure in
the induction system to a closed position when the presure in
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the induction system becomes positive or atmospheric so that
operation of the control devices is prevented~ The control
mechanism employs a diaphragm assembly which moves all control
valves simultaneously between their open and closed positions
to regulate separate fluid flow paths.
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