CROSS-REFERENCE TO RELATED APPLICATIONS
FIELD
[0002] The present disclosure relates generally to emergency oxygen supply systems and,
more particularly, to intelligent controllers for oxygen systems for aircrafts.
BACKGROUND
[0003] Emergency oxygen supply systems are commonly installed on aircraft for the purpose
of supplying oxygen to passengers upon loss of cabin pressure at altitudes above about
12,000 feet. Such systems typically include a face mask adapted to fit over the mouth
and nose which is released from an overhead storage compartment when needed. Supplemental
oxygen delivered by the mask increases the level of blood oxygen saturation in the
mask user beyond what would be experienced if ambient air were breathed at the prevailing
cabin pressure altitude condition. The flow of oxygen provided thereby is calculated
to be sufficient to sustain all passengers until cabin pressure is reestablished or
until a lower, safer altitude can be reached.
[0004] Each such face mask may have a reservoir bag attached thereto into which a constant
flow of oxygen is directed upon deployment of the system and upon activation of the
individual face mask via a pull cord. The oxygen is supplied continuously at a rate
that is calculated to accommodate a worst-case scenario, namely to satisfy the need
of a passenger with a significantly larger than average tidal volume who is breathing
at a faster than average respiration rate in response to cabin pressure loss at a
maximum cruising altitude. A total of three valves that are associated with the mask
serve to coordinate flows between the bag and the mask, and between the mask and the
surroundings. An inhalation valve serves to confine the oxygen flowing into the bag
to the bag while the passenger is exhaling as well as during the post-expiratory pause
and at all times also prevents any flow from the mask into the bag. In response to
the passenger inhaling, the inhalation valve opens to allow for the inhalation of
the oxygen that has accumulated in the bag. Upon depletion of the accumulated oxygen,
the dilution valve opens to allow cabin air to be drawn into the mask. The continuing
flow of oxygen into the bag and through the open inhalation valve into the mask is
thereby diluted by the cabin air that is inhaled during the balance of the inhalation
phase. During exhalation, the exhalation valve opens to allow a free flow from the
mask into the surroundings while the inhalation valve closes to prevent flow from
the mask back into the bag. All three valves remain closed during the post-expiratory
pause while oxygen continues to flow into the reservoir bag.
[0005] Inefficiencies in an emergency oxygen supply system may cause the oxygen storage
or oxygen generation means to be larger and therefore weigh more, which has an adverse
impact on the payload capacity and fuel consumption of the aircraft.
SUMMARY
[0006] An oxygen supply system for delivering oxygen to passengers in an aircraft in an
event of a loss of cabin pressure is disclosed herein. The oxygen supply system includes
a source of oxygen, a passenger service unit, and a main controller. The passenger
service unit includes a face mask configured to facilitate a flow of a bolus volume
of oxygen from the source of oxygen, and a sensor configured to detect at least one
of an ambient pressure, an airflow in a first direction, or an airflow in a second
direction. The main controller is configured to determine at least one of the ambient
pressure, the airflow being in the first direction, or the airflow being in the second
direction, and command delivery of oxygen from the source of oxygen to the face mask
in response to the determination.
[0007] In various embodiments, the oxygen supply system includes a plurality of passenger
service units. The main controller is configured to control each of the plurality
of passenger service units.
[0008] In various embodiments, the source of oxygen supplies each of the plurality of passenger
service units.
[0009] In various embodiments, the source of oxygen includes a container of compressed oxygen
gas.
[0010] In various embodiments, an inlet valve of the passenger service unit remains closed
in response to the airflow being in the first direction.
[0011] In various embodiments, the inlet valve is opened in response to the airflow being
in the second direction.
[0012] In various embodiments, the accumulated volume of oxygen is delivered to a reservoir
bag coupled to the face mask prior in response to the airflow being in the second
direction to meter a constant flow.
[0013] In various embodiments, the main controller is configured to open and close the inlet
valve.
[0014] In various embodiments, the main controller is configured to determine a volume of
oxygen as a function of at least one of the ambient pressure or a rate of airflow
being above a predetermined threshold.
[0015] An article of manufacture including a tangible, non-transitory computer-readable
storage medium having instructions stored thereon for controlling a passenger service
unit, in response to execution by a controller, cause the controller to perform operations
is disclosed herein. The operations include determining at least one of an ambient
pressure of an aircraft cabin or an airflow through a face mask in a first direction,
or an airflow through the face mask in a second direction, and commanding delivery
of oxygen from a source of oxygen to the face mask in response to the determination.
[0016] In various embodiments, the passenger service unit comprises the face mask and a
sensor. The face mask is configured to facilitate a flow of an accumulated volume
of oxygen from a source of oxygen. The sensor is configured to detect at least one
of the ambient pressure, the airflow being in the first direction, or the airflow
being in the second direction.
[0017] In various embodiments, the controller is configured to communicate with the sensor
such that the operations further comprise receiving data from the sensor, the data
indicative of at least one of the ambient pressure of the aircraft cabin, the airflow
being in the first direction, or the airflow being in the second direction.
[0018] In various embodiments, the operations further include controlling a plurality of
passenger service units. The controller is operatively coupled to each of the plurality
of passenger service units.
[0019] In various embodiments, the operations further include commanding delivery of oxygen
from the source of oxygen to each of the plurality of passenger service units.
[0020] In various embodiments, the source of oxygen includes a container of compressed oxygen
gas.
[0021] In various embodiments, the operations further include commanding an inlet valve
to open and commanding the inlet valve to close.
[0022] In various embodiments, the inlet valve of the passenger service unit remains closed
in response to the airflow being in the first direction.
[0023] In various embodiments, the inlet valve is opened in response to the airflow being
in the second direction.
[0024] In various embodiments, the accumulated volume of oxygen is delivered to a reservoir
bag coupled to the face mask in response to the airflow being in the second direction
to meter a constant flow.
[0025] In various embodiments, the operations further include determining the volume of
oxygen as a function of at least one of the ambient pressure or a rate of airflow
being above a predetermined threshold.
[0026] The forgoing features and elements may be combined in various combinations without
exclusivity, unless expressly indicated herein otherwise. These features and elements
as well as the operation of the disclosed embodiments will become more apparent in
light of the following description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The subject matter of the present disclosure is particularly pointed out and distinctly
claimed in the concluding portion of the specification. A more complete understanding
of the present disclosure, however, may best be obtained by referring to the following
detailed description and claims in connection with the following drawings. While the
drawings illustrate various embodiments employing the principles described herein,
the drawings do not limit the scope of the claims.
FIG. 1A illustrates a view of a cabin of an aircraft, in accordance with various embodiments;
FIG. 1B illustrates a perspective view of a cabin of an aircraft, in accordance with
various embodiments;
FIG. 2 illustrates a schematic view of an oxygen system, in accordance with various
embodiments;
FIG. 3 illustrates a schematic view of an oxygen system, in accordance with various
embodiments;
FIG. 4 illustrates a schematic view of an oxygen system, in accordance with various
embodiments; and
FIG. 5 illustrates a schematic view of a main controller of an oxygen system, in accordance
with various embodiments.
DETAILED DESCRIPTION
[0028] The following detailed description of various embodiments herein makes reference
to the accompanying drawings, which show various embodiments by way of illustration.
While these various embodiments are described in sufficient detail to enable those
skilled in the art to practice the disclosure, it should be understood that other
embodiments may be realized and that changes may be made without departing from the
scope of the disclosure. Thus, the detailed description herein is presented for purposes
of illustration only and not of limitation. Furthermore, any reference to singular
includes plural embodiments, and any reference to more than one component or step
may include a singular embodiment or step. Also, any reference to attached, fixed,
connected, or the like may include permanent, removable, temporary, partial, full
or any other possible attachment option. Additionally, any reference to without contact
(or similar phrases) may also include reduced contact or minimal contact. It should
also be understood that unless specifically stated otherwise, references to "a," "an"
or "the" may include one or more than one and that reference to an item in the singular
may also include the item in the plural. Further, all ranges may include upper and
lower values and all ranges and ratio limits disclosed herein may be combined.
[0029] With reference to FIG. 1A, a cabin 51 of an aircraft 50 is shown, according to various
embodiments. The aircraft 50 may be any aircraft such as an airplane, a helicopter,
or any other aircraft. The aircraft 50 may include a passenger service unit (PSU)
10 corresponding to each row of seats 62. The cabin 51 may include overhead bins 52,
passenger seats 54 forming the row of passenger seats 62 for supporting passengers
55, etc. In various embodiments, the PSU 10 may be integral with the overhead bins
52 or the PSU 10 may be separate from the overhead bins 52. The present disclosure
is not limited in this regard.
[0030] Referring now to FIG. 1B, a perspective view of the cabin 51 of the aircraft 50 from
FIG. 1A is illustrated with a plurality of oxygen mask assemblies 70 in a deployed
position. Each mask assembly in the plurality of oxygen mask assemblies 70 may be
deployed from a PSU 10. Each PSU may comprise a release mechanism (e.g., release mechanism
112, 122, 132), such as an actuator based lock or the like. The present disclosure
is not limited in this regard and any release mechanism is within the scope of this
disclosure.
[0031] In various embodiments, each oxygen mask assembly in the plurality of oxygen mask
assemblies 70 comprises a tube assembly 201. The tube assembly 201 is configured to
transfer a fluid (e.g., oxygen gas) from an oxygen source, or a compressed oxygen
gas, to a respective oxygen mask 72. In this regard, each tube assembly (e.g., tube
assembly 201) may comprise a fluid conduit configured to transfer the fluid from the
oxygen source to the respective oxygen mask 72.
[0032] Referring now to FIG. 2 a schematic view of an oxygen system 100 for an aircraft
cabin, is illustrated, in accordance with various embodiments. In various embodiments,
the oxygen system 100 comprises a main control system 101 and a plurality of PSUs
(e.g., first PSU 110, second PSU 120, third PSU 130, fourth PSU 140, etc.). Although
illustrated as including three PSUs, the number of PSUs of an oxygen system 100 is
not limited in this regard. For example, a PSU may be disposed in each row of seats
disposed in a respective column of an aircraft cabin. For example, a cabin with 50
rows and 3 columns may have 150 PSUs (e.g., each row in each column having a PSU).
In various embodiments, the PSUs are not limited to rows in the aircraft cabin and
may be placed throughout the aircraft cabin as well.
[0033] In various embodiments, the main control system 101 includes a controller 102 (e.g.,
a main controller) and a memory 104 (e.g., a database or any appropriate data structure;
hereafter "memory 104" also may be referred to as "database 104"). The controller
102 may include one or more logic devices such as one or more of a central processing
unit (CPU), an accelerated processing unit (APU), a digital signal processor (DSP),
a field programmable gate array (FPGA), an application specific integrated circuit
(ASIC), or the like (e.g., controller 102 may utilize one or more processors of any
appropriate type/configuration, may utilize any appropriate processing architecture,
or both). In various embodiments, the controller 102 may further include any non-transitory
memory known in the art. The memory 104 may store instructions usable by the logic
device to perform operations. Any appropriate computer-readable type/configuration
may be utilized as the memory 104, any appropriate data storage architecture may be
utilized by the memory 104, or both.
[0034] The database 104 may be integral to the control system 101 or may be located remote
from the control system 101. The controller 102 may communicate with the database
104 via any wired or wireless protocol. In that regard, the controller 102 may access
data stored in the database 104. In various embodiments, the controller 102 may be
integrated into computer systems onboard an aircraft. Furthermore, any number of conventional
techniques for electronics configuration, signal processing and/or control, data processing
and the like may be employed. Also, the processes, functions, and instructions may
include software routines in conjunction with processors, etc.
[0035] System program instructions and/or controller instructions may be loaded onto a non-transitory,
tangible computer-readable medium having instructions stored thereon that, in response
to execution by the processor, cause the controller 102 to perform various operations.
The term "non-transitory" is to be understood to remove only propagating transitory
signals per se from the claim scope and does not relinquish rights to all standard
computer-readable media that are not only propagating transitory signals per se.
[0036] The instructions stored on the memory 104 of the controller 102 may be configured
to perform various operations, such as determining a cabin air pressure has dropped
below a threshold pressure, commanding release of a plurality of oxygen masks, initiating
a start of chemical oxygen generators, etc.
[0037] In various embodiments, the main control system 101 from FIG. 2 further comprises
a power source 108 and sensor(s) 106. The power source 108 may comprise any power
source known in the art, such as a battery, a solar source, an alternating current
(AC) source, a rechargeable source, or the like. In various embodiments, the sensor(s)
106 may be spaced about the aircraft 50 from FIG. 1A. In various embodiments, the
sensor(s) 106 may comprise pressure sensors. In this regard, the sensor(s) 106 may
be configured to measure an aircraft cabin pressure and relay the measurements to
the controller 102. Thus, the controller 102 may determine whether the aircraft pressure
has dropped below a pressure threshold, and release the oxygen masks as described
further herein.
[0038] In various embodiments, the sensors 106 may comprise any type of sensor that measures
oxygen flowing properly in the oxygen system 100 (e.g., an oxygen gas detector, an
oxygen sensor, or the like). The present disclosure is not limited in this regard.
In various embodiments, the sensors 106 may be external to the tube assembly 201 or
integrated within the tube assembly 201. In various embodiments, the sensors 204 may
be disposed within a fluid conduit of the tube assembly 201 as described further herein.
[0039] In various embodiments, the main control system 101 is in operable communication
with each PSU in the plurality of PSUs (e.g., PSUs 110, 120, 130). In various embodiments,
each PSU comprises a local controller (e.g., controllers 111, 121, 131, 141). The
local controllers 111, 121, 131, 141 may be configured to communicate with the main
control system 101 located outside the PSU by ethernet, CAN, or another network communication
protocol. Each local controller (e.g., controllers 111, 121, 131) may be in accordance
with controller 102. For example, each local controller (e.g., controllers 111, 121,
131) may include one or more logic devices such as one or more of a central processing
unit (CPU), an accelerated processing unit (APU), a digital signal processor (DSP),
a field programmable gate array (FPGA), an application specific integrated circuit
(ASIC), or the like (e.g., controllers 111, 121, 131) may utilize one or more processors
of any appropriate type/configuration, may utilize any appropriate processing architecture,
or both). In various embodiments, the controllers 111, 121, 131 may each further include
any non-transitory memory known in the art. The memory may store instructions usable
by the logic device to perform operations. Any appropriate computer-readable type/configuration
may be utilized as the memory, any appropriate data storage architecture may be utilized
by the memory, or both.
[0040] In various embodiments, each PSU (e.g., PSUs 110, 120, 130) may comprise a release
mechanism (e.g., release mechanism 112, 122, 132), an oxygen source (e.g., oxygen
source 113, 123, 133), and oxygen mask assemblies (e.g., oxygen mask assemblies 114,
124, 134, 144). In various embodiments, the controller 102 may command the various
local controllers (e.g., controllers 111, 121, 131) to instruct the devices therein.
For example, the controller 102 may command the release mechanisms 112, 122, 132 to
release the oxygen mask assemblies 114, 124, 134, command the oxygen source 113, 123,
133 to activate, etc.
[0041] Referring now to FIG. 3-5, in various embodiments, the oxygen system 100 includes
an oxygen cylinder assembly (OCA) 126. In various embodiments, the OCA 126 may be
located inside the oxygen box of the plurality of PSUs 110, 120, 130. The OCA may
be connected to the oxygen mask assemblies 114, 124, 134. The OCA 126 may comprise
of a high pressure oxygen bottle, pressure regulator and electrical or mechanical
initiator. The PSUs 110, 120, 130 may further comprise a low pressure manifold 136
and at least one solenoid or proportional valve 138. The solenoid valve 138 is configured
to dispense oxygen to the mask assemblies 114, 124, 134. For instance, a first solenoid
valve 138a is connected to mask assembly 114, a second solenoid valve 138b is connected
to mask assembly 124, a third solenoid valve 138c is connected to mask assembly 134,
and a fourth solenoid valve 138d is connected to mask assembly 144. The controller
102 may be configured to monitor the manifold pressure and temperature of the oxygen
system 100. For instance, as shown in FIG. 5, a schematic of a main centralized intelligent
controller (e.g., main controller 101), the main controller 101 may include a communications
module 140. The communications module 140 is configured to determine a pressure and/or
temperature reading from sensors 106 and send a signal to the PSUs 110, 120, 130 in
response to the determination. The communication modules 140 of the main control system
101 is further configured to initiate the OCA 126 and manage the delivery of oxygen
to the passengers.
[0042] Activation of an individual passenger interface is accomplished by selecting a face
mask and breathing thereinto. An exhalation is detected by a sensor (e.g., sensor
106) which causes controller 101 to open the inlet valve that is associated with the
face mask to allow the influx of oxygen. For instance, in various embodiments, the
oxygen system 100 includes reservoir bags such that the inlet valve that is associated
with the face mask allows the influx of oxygen into the associated reservoir bag.
The controller 101 is configured to calculate the volume of oxygen needed in light
of the ambient cabin pressure measured via an ambient pressure sensor and closes the
inlet valve after an appropriate period of time. In various embodiments, the controller
101 is configured to calculate the volume of oxygen needed in light of a rate of airflow
(e.g., a passenger's breathing pattern) being above a predetermined threshold. The
system's oxygen pressure may be regulated to a level such that the desired volume
of oxygen is deliverable to the reservoir bag well within the period of time needed
for exhalation. During the passenger's post-expiratory pause, the delivered oxygen
may be held in the reservoir bag. Upon inhalation, the inhalation valve allows all
the oxygen within the reservoir bag to be inhaled to fill the passenger's lower lung
lobes where the most efficient oxygen transfer takes place. Upon depletion of the
contents of the reservoir bag, further inhalation causes the mask's dilution valve
to open so as to allow the passenger's respiratory demand to be satisfied by ambient
cabin air. Exhalation causes the sequence to repeat. In various embodiments, the controller
101 is configured to deliver oxygen without the reservoir bag.
[0043] In other words, the face mask (e.g., face mask assemblies 114, 124, 134, 144) are
configured to facilitate a flow of the accumulated volume of oxygen from the source
of oxygen (e.g., OCA 126). Contemporaneously, the sensor 106 detects at least one
of an ambient pressure, an airflow through the face mask in a first direction, or
an airflow through the face mask a second direction. For instance, airflow in the
first direction may indicate an inhale by the passenger and airflow in the second
direction may indicate an exhale by the passenger. Then the controller 106 may determine
at least one of the ambient pressure, the airflow being in the first direction, or
the airflow being in the second direction, and command delivery of oxygen from the
source of oxygen to the face mask in response to the determination. For instance,
the inlet valve of the passenger service unit (e.g., PSU 110, 120, 130, 140) remains
closed with the airflows in the first direction, and the controller controllers the
inlet valve to open in response to the airflow flowing in the second direction.
[0044] The configuration of the system causes the frequency with which the oxygen is delivered
to match the frequency of the respiratory rate of the passenger breathing therefrom.
Should the volume of oxygen that is received by a particular passenger fail to satisfy
that particular passenger's oxygen demand, the respiratory rate would be expected
to increase to thereby increasing the frequency with which the allotments of oxygen
are delivered to the passenger. Conversely, should the volume of oxygen that is received
by a particular passenger during each respiratory cycle exceed such passenger's oxygen
requirement, the passenger's respiratory rate would be expected to decrease, thereby
decreasing the net flow of oxygen to the passenger.
[0045] By substantially matching the delivery of oxygen to a passenger's demand therefor,
the efficiency of an emergency oxygen supply system is maximized and oxygen consumption
is minimized. Such an increase in efficiency allows the size of the oxygen supply
to be reduced when compared with less efficient systems such as are currently in use
and thereby allows a substantial weight reduction to be realized. The weight reduction
in turn translates into a reduction in an aircraft's fuel consumption and/or an increase
in payload capacity.
[0046] Further, the use of an intelligent controller (e.g., main control system 101 with
controller 102) allows for the implementation of more sophisticated predictive control
algorithms that can better account for breathing variabilities between passengers.
Controller 102 may further be configured to calculate the remaining oxygen in the
bottle and predict when the bottle will be depleted and generate a notification accordingly.
Having the centralized controller 102 creates more space in the PSU to increase the
amount of stored oxygen, or provide more space for masks which will help reduce tangles
during deployment.
[0047] Accordingly, as described herein the controller 102 is configured to controller the
plurality of PSUs 110, 120, 130 in lieu of the local controller (e.g., controllers
111, 121, 131). The oxygen system 100 may be configured to have the capacity to support
the plurality of controllers 102 such that, if an intelligent controller fails, then
its responsible oxygen panels will be reassigned to other controllers. The oxygen
system 100 thus provides redundancy in a safety critical system. Additionally, the
controller 102 may be configured to perform health monitoring, and report issues to
the flight crew or schedule maintenance. Health status and operational status can
be sent to a flight crew screen and inform them if one panel or valve is not operational
so that the crew member can act accordingly. The oxygen system 100 may be integrated
with other smart interior systems to provide information to the flight crew without
duplicating hardware components. In various embodiments, a plurality of intelligent
controllers (e.g., controller 102) may be used to dispense oxygen to passengers.
[0048] Referring now to FIG. 4, in various embodiments, the OCA 126 may be located outside
of the oxygen box of the plurality of PSUs 110, 120, 130. The OCA 126 may be connected
to the oxygen panels with plastic or steel flexible tubing, along with quick disconnects
or threaded connections. In such configuration, the weight of the oxygen system 100
is reduced by reducing the number of OCAs on the aircraft, and larger lighter weight
composite cylinders may be used in the oxygen system 100. Further, removing the OCAs
from the PSUs will allow for a more reliable mask pack and easier maintenance checks.
[0049] Benefits, other advantages, and solutions to problems have been described herein
with regard to specific embodiments. Furthermore, the connecting lines shown in the
various figures contained herein are intended to represent exemplary functional relationships
and/or physical couplings between the various elements. It should be noted that many
alternative or additional functional relationships or physical connections may be
present in a practical system. However, the benefits, advantages, solutions to problems,
and any elements that may cause any benefit, advantage, or solution to occur or become
more pronounced are not to be construed as critical, required, or essential features
or elements of the disclosure. The scope of the disclosure is accordingly to be limited
by nothing other than the appended claims, in which reference to an element in the
singular is not intended to mean "one and only one" unless explicitly so stated, but
rather "one or more." Moreover, where a phrase similar to "at least one of A, B, or
C" is used in the claims, it is intended that the phrase be interpreted to mean that
A alone may be present in an embodiment, B alone may be present in an embodiment,
C alone may be present in an embodiment, or that any combination of the elements A,
B and C may be present in a single embodiment; for example, A and B, A and C, B and
C, or A and B and C. Different cross-hatching is used throughout the figures to denote
different parts but not necessarily to denote the same or different materials.
[0050] Systems, methods and apparatus are provided herein. In the detailed description herein,
references to "one embodiment," "an embodiment," "various embodiments," etc., indicate
that the embodiment described may include a particular feature, structure, or characteristic,
but every embodiment may not necessarily include the particular feature, structure,
or characteristic. Moreover, such phrases are not necessarily referring to the same
embodiment. Further, when a particular feature, structure, or characteristic is described
in connection with an embodiment, it is submitted that it is within the knowledge
of one skilled in the art to affect such feature, structure, or characteristic in
connection with other embodiments whether or not explicitly described. After reading
the description, it will be apparent to one skilled in the relevant art(s) how to
implement the disclosure in alternative embodiments.
[0051] Furthermore, no element, component, or method step in the present disclosure is intended
to be dedicated to the public regardless of whether the element, component, or method
step is explicitly recited in the claims. As used herein, the terms "comprises," "comprising,"
or any other variation thereof, are intended to cover a non-exclusive inclusion, such
that a process, method, article, or apparatus that comprises a list of elements does
not include only those elements but may include other elements not expressly listed
or inherent to such process, method, article, or apparatus.
[0052] Finally, it should be understood that any of the above described concepts can be
used alone or in combination with any or all of the other above described concepts.
Although various embodiments have been disclosed and described, one of ordinary skill
in this art would recognize that certain modifications would come within the scope
of this disclosure. Accordingly, the description is not intended to be exhaustive
or to limit the principles described or illustrated herein to any precise form. Many
modifications and variations are possible in light of the above teaching.
1. An oxygen supply system (100) for delivering oxygen to passengers in an aircraft in
an event of a loss of cabin pressure, comprising:
a source of oxygen (113, 123, 133);
a passenger service unit (110, 120, 130) comprising:
a face mask (114, 124, 134) configured to facilitate a flow of an accumulated volume
of oxygen from the source or a bolus of oxygen; and
a sensor (106) configured to detect at least one of an ambient pressure, an airflow
in a first direction, or an airflow in a second direction; and
a main controller (101) operatively coupled to the passenger service unit, the main
controller configured to:
determine at least one of the ambient pressure, the airflow being in the first direction,
or the airflow being in the second direction; and
command delivery of oxygen from the source of oxygen to the face mask in response
to the determination.
2. The oxygen supply system (100) of claim 1, further comprising a plurality of passenger
service units (110, 120, 130), wherein the main controller (102) is configured to
control each of the plurality of passenger service units; optionally wherein the source
of oxygen supplies each of the plurality of passenger service units.
3. The oxygen supply system (100) of claim 1 or 2, wherein the source of oxygen (113,
123, 133) comprises a container of compressed oxygen gas.
4. The oxygen supply system (100) of any preceding claim, wherein an inlet valve of the
passenger service unit (110, 120, 130) remains closed in response to the airflow being
in the first direction.
5. The oxygen supply system (100) of claim 4, wherein the inlet valve is opened in response
to the airflow being in the second direction.
6. The oxygen supply system (100) of claim 5, wherein the accumulated volume of oxygen
is delivered to a reservoir bag coupled to the face mask (114, 124, 134) prior in
response to the airflow being in the second direction to meter a constant flow.
7. The oxygen supply system (100) of any of claims 4 to 6, wherein the main controller
(101) is configured to open and close the inlet valve.
8. The oxygen supply system (100) of claim 7, wherein the main controller (101) is configured
to determine a volume of oxygen as a function of at least one of the ambient pressure
or a rate of airflow being above a predetermined threshold.
9. An article of manufacture including a tangible, non-transitory computer-readable storage
medium having instructions stored thereon for controlling a passenger service unit
(110, 120, 130), in response to execution by a controller (101), cause the controller
to perform operations comprising:
determining at least one of an ambient pressure of an aircraft cabin or an airflow
through a face mask (114, 124, 134) in a first direction, or an airflow through the
face mask in a second direction; and
commanding delivery of oxygen from a source of oxygen to the face mask in response
to the determination.
10. The article of manufacture of claim 9, wherein the passenger service unit (110, 120,
130) comprises the face mask (114, 124, 134) and a sensor (106) , wherein the face
mask is configured to facilitate a flow of an accumulated volume of oxygen from a
source of oxygen, and the sensor is configured to detect at least one of the ambient
pressure, the airflow being in the first direction, or the airflow being in the second
direction; optionally
wherein the controller (101) is configured to communicate with the sensor such that
the operations further comprise receiving data from the sensor, the data indicative
of at least one of the ambient pressure of the aircraft cabin, the airflow being in
the first direction, or the airflow being in the second direction.
11. The article of manufacture of claim 9 or 10, wherein the operations further comprise
controlling a plurality of passenger service units (114, 124, 134), wherein the controller
(102) is operatively coupled to each of the plurality of passenger service units;
optionally
wherein the operations further comprise commanding delivery of oxygen from the source
of oxygen to each of the plurality of passenger service units.
12. The article of manufacture of any of claims 9 to 11, wherein the source of oxygen
(113, 123, 133) comprises a container of compressed oxygen gas.
13. The article of manufacture of any of claims 9 to 12, wherein the operations further
comprise commanding an inlet valve to open and commanding the inlet valve to close.
14. The article of manufacture of claim 13, wherein the inlet valve of the passenger service
unit (110, 120, 130) remains closed in response to the airflow being in the first
direction; and/or
wherein the inlet valve is opened in response to the airflow being in the second direction;
and/or
wherein the accumulated volume of oxygen is delivered to a reservoir bag coupled to
the face mask in response to the airflow being in the second direction to meter a
constant flow.
15. The article of manufacture of any of claims 9 to 14, wherein the operations further
comprise determining the volume of oxygen as a function of at least one of the ambient
pressure or a rate of airflow being above a predetermined threshold.