Abstract:
An apparatus for deploying oxygen masks that includes a pre-packaged modular system that does not require manual repacking of oxygen masks by aircraft technicians. The cartridge is for use with a manifold having a passageway in fluid communication with a source of breathable gas. The cartridge includes an end wall, a sidewall extending from the end wall and terminating at a distal end adjacent to an opening. A flexible member defines a chamber inside the cartridge. The chamber is in fluid communication with the passageway when the cartridge is coupled to the manifold. The flexible member has an outlet. A mask assembly is disposed inside the cartridge. The mask assembly has a hose coupled to the outlet of the flexible member. A cover is removably attached to the distal end of the at least one side wall.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation-in-part of U.S. Pat. No. 8,356,595 issued on Jan. 22, 2013, which is a continuation of U.S. Pat. No. 8,443,802 filed on May 21, 2013, which claims benefit of U.S. Provisional Patent Application No. 60/643,449 filed on Jan. 13, 2005, titled “Method and Apparatus for Deploying Oxygen Masks,” all of which applications are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a method and apparatus for deploying an emergency breathing mask in an aircraft. The apparatus is automatically or manually operable to present the breathing mask to a user upon loss of cabin pressurization. 
     BACKGROUND OF THE INVENTION 
     As shown in  FIG. 1A , typical emergency breathing mask deployment systems include a generally rectangular shaped storage container  12  carrying a fluid valve assembly  14 , one or more oronasal oxygen masks  16  and means, generally indicated at  18 , for supporting masks  16  thereon in a stowed condition within container  12 . As known to those of ordinary skill in the art, the masks  16  have to be stowed in such a way that they will unfold during deployment without tangling. With the conventional systems, the masks  16  may have to be repacked in the container  12  by aircraft technicians several times during the usable life of the container  12  and/or aircraft. For example, the masks  16  may have to be replaced after a predetermined period of time, the masks may have to be repacked after inspection or they may have to be repacked after a deployment. In order to repack the masks  16  in the container  12 , components, which typically include the oxygen tubes  29 , reservoir bag  38 , elastic strap  34  and lanyards  60 , must be carefully folded and coiled as shown in  FIG. 1B  so that the mask  16  deploys properly and does not become tangled during an emergency situation. The process of repacking masks is time-consuming and costly given the labor rates of aircraft technicians. 
     Accordingly, there is a need for a method and apparatus that eliminates the need to have aircraft technicians manually repack oxygen masks during service-related replacement of masks. In addition while most masks are mounted in the ceilings of aircraft, some aircraft will require mounting in the sidewalls or as part of a seat assembly. In these aircraft there is a need for an emergency mask system that can be deployed by forces other than gravity. There is also a need for a method and apparatus that meets both needs. 
     SUMMARY OF THE INVENTION 
     The present invention meets the above-described need by providing a method and apparatus for presenting oxygen masks that provides a pre-packaged, modular system that does not require manual repacking of oxygen masks by aircraft technicians. The system also provides a force other than gravity for deploying the masks. It is to be understood that the present invention may be used in a ceiling mounted orientation where it would provide a force in addition to gravity for releasing the masks. The system may be embodied as a modular deployment system having an oxygen source, and an embodiment is provided wherein the oxygen source is proximate to and/or attached to the modular deployment system. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1A  is a perspective view of a prior art emergency mask deployment system showing the oxygen masks dropped free from the container; 
         FIG. 1B  is a perspective view of an oxygen mask folded for deployment inside the container; 
         FIG. 2  is a front elevational view of an individual mask cartridge of the present invention; 
         FIG. 3  is an elevational view showing three ports for receiving the individual cartridges; 
         FIG. 4  is an elevational view showing the present invention in relation to an access door; 
         FIG. 5  is an elevational view showing an alternate embodiment of the present invention; 
         FIG. 6A  is an elevational, cross-sectional view of an alternate embodiment of the cartridge of the present invention; 
         FIG. 6B  is an elevational, cross-sectional view of an alternate embodiment of the cartridge shown in  FIG. 6A ; 
         FIG. 6C  is a cross-sectional view of a cartridge with a valve located between the diaphragm and the hose to the mask assembly; 
         FIG. 6D  is a cross-sectional view of an alternate embodiment of the valve for controlling flow to the mask assembly; 
         FIG. 6E  is a cross-sectional view of another alternate embodiment showing a valve for controlling flow to the mask assembly; 
         FIG. 7  is an elevational, cross-sectional view of an alternate embodiment of the cartridge of the present invention; 
         FIG. 8  is a front elevational view of a plurality of cartridges attached to a manifold; 
         FIG. 9  is a perspective view of the cartridges and manifold shown in  FIG. 8 ; 
         FIG. 10  is a partial elevational cross-sectional view of an alternate embodiment of the manifold; 
         FIG. 11  is a cross-sectional elevational view of an alternate embodiment of the cartridge of the present invention; 
         FIG. 12  is a partial elevational cross-sectional view of an alternate embodiment of the cartridge and manifold of the present invention; and 
         FIG. 13  is a side elevational view of a system having an attached oxygen source according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 2 , a cartridge  100 , which may be in the shape of a cylinder, contains a single oxygen mask assembly  103 . As will be evident to those of ordinary skill in the art, the oxygen mask assembly  103  may include the following major components: a folded reservoir bag  106 , an oronasal mask  109 , a strap  112 , and breathing conduit  115 . The cartridge  100  is provided with side walls  118  and an end wall  121 . The end wall  121  is provided with an opening  124  for receiving a quick connect fitting that is in fluid communication with the conduit on the mask assembly. Opposite from the end wall  121 , the cartridge  100  has an opening  127  where the mask  109  exits the cartridge  100  during deployment. The opening  127  may be initially covered or partially covered by a removable substrate  130  which may be provided with a pressure-sensitive adhesive or the like. Alternately, the substrate  130  may be creased, scored, or perforated such that it will split open during deployment of the mask. The substrate  130  covers the opening  127  to hold the mask assembly  103  in position during installation of the cartridge  100  and may also prevent contamination. The cartridge  100  is a pre-packed standalone assembly that is intended to be installed in the field without requiring any handling of individual mask components by aircraft technicians. Accordingly, the cartridge  100  is provided with quick connect oxygen line connections and quick connect mechanical connections such as quarter-turn bayonet (not shown), pin and slot connections ( FIG. 6-9 ), or “push and stab” connections ( FIG. 12 ) that provide for quick installation in the field without the requirement of tools or separate fasteners. However, it is to be understood that the cartridge  100  can also be installed with tools and separate fasteners. 
     In addition to being a pre-packed modular construction, the cartridge  100  includes a supplemental mask ejection device such as the spring-biased piston  131  shown in  FIG. 2 . The piston  131  is biased by a pair of coil springs  133  disposed in grooves  135  in the back of the piston  131 . When an electrical signal is given or when the oxygen flow is activated, the spring  133  is released from a retention mechanism and provides a force on the piston  131  in the downward direction with respect to the orientation of  FIG. 2 . This force ejects the mask  109  from its cartridge to present it to the user. 
     As will be evident to those of ordinary skill in the art, the mask ejection device may be formed as part of the cartridge, as part of the housing or oxygen manifold (as shown and described herein in connection with  FIGS. 10-12 ) or as a part of some or all of the above components. Also, in order to eliminate the ejection device from the cartridge, the cartridge may be provided with an end wall that is responsive to force from an ejection device mounted on the manifold. Also, the cartridge may be formed with one or more openings in the top and the one or more openings may be covered by a flexible covering such that the ejection device may act upon the mask  109  to deploy it. 
     Turning to  FIG. 3 , a bank of cartridges are shown. On the left side with respect to the orientation of  FIG. 3 , cartridge  100  is shown with the mask removed for clarity. As shown, the cartridge  100  includes a quick connect fitting for attaching to a manifold  140 . In the other positions along the manifold  140 , alternate embodiments for the cartridge are shown. In the middle position, a cartridge  150  is shown. The cartridge  150  includes a piston  153  sealed with O-rings  156 . The piston  153  is actuated by the pressure of the oxygen and ejects the mask from its cartridge. In the right hand position, another alternate gas pressure actuated piston is shown with cup seals  159  to form the pressure chamber above the piston. 
     In  FIG. 4 , a pair of cartridges  100  and  150  are shown in relation to the door  160  leading to the inside of the aircraft cabin. As shown, the door  160  may be opened by a solenoid-operated actuator  163 . As an alternative, the door  160  could be held by a mechanically operated latch capable of being released by the force of the ejection of the mask  109 . 
     Once the door  160  is opened, the mask  109  is ejected from its cartridge by the force of the piston which may be spring-biased or pressure actuated as described above. If the flow of oxygen is initiated when the masks are presented, then the masks may be ejected by pneumatic pressure as described above. 
     Turning to  FIG. 5 , in an alternate embodiment of the invention, mask  109  is ejected from cartridge  180  by a bellows chamber  183 . When the flow of oxygen is initiated the bellows chamber  183  fills with oxygen causing it to expand and push the mask  109  downward with respect to the orientation of  FIG. 5 . 
     In  FIG. 6A , an alternate embodiment of the cartridge is shown. Cartridge  200  includes side walls  203  and an end wall  206 . Extending from end wall  206  are a pair of studs  209  that can be used for attaching the cartridge  200  to a support structure. The studs have a body portion  212  and an enlarged head  215  for engaging with a slot having an enlarged opening leading to a slot. By inserting the head  215  into the enlarged opening and rotating the cartridge  200 , the body portion  212  can be received and retained by the slot as will be evident to those of ordinary skill in the art. 
     In the center of the end wall  206  there is an opening  207  surrounded by an adapter  218 . The adapter  218  is provided with an O-ring  221  capable of engaging with the oxygen manifold to provide for fluid communication between the oxygen manifold and the oxygen conduit  224  in the cartridge  200 . Other connecting means such as quick connects and the like could also be used and the cartridge  200  could therefore be supported from these other structures disposed around the central opening. As shown the adapter  218  leads to a bladder  227  the outlet of which is in fluid communication with the conduit  224 . The conduit  224  is coiled above the remaining components such as the reservoir bag, straps, and oronasal mask. A cover  230  is attached to the cartridge  200  at the end opposite from the end wall  206 . In operation, the flow of oxygen from the manifold into the bladder  227  causes the bladder  227  to expand and force the mask assembly to push the cover  230  off of the cartridge and causes the mask assembly to exit the cartridge  200 . 
     In  FIG. 6B , a variation of the bladder  227  is shown. A diaphragm  250  is formed from a flexible sheet of material. The diaphragm  250  may be attached on opposite sides of the cartridge  253  at midwall between the top  256  and bottom  259  of the cartridge. The cartridge  253  has a central opening  268  which is surrounded by a gasket  271  when the cartridge  253  is in position. The central opening  268  is in fluid communication with gas passageway  274  in the manifold  265 . 
     A mask assembly  277  (including straps, etc. as described above in connection with  FIG. 2 ) is provided for delivering the breathing gas to the user. A hose assembly  280  connects the mask assembly  277  to a fitting  283  on the diaphragm  250 . The mask assembly  277  and hose assembly  280  are folded and stowed in the cartridge  253  prior to use (as shown in  FIG. 6A ). 
     As shown in  FIG. 6B , upon actuation the flow of breathing gas in the direction of arrow  284  from the manifold  265  causes the diaphragm  250  to move downward with respect to the orientation of  FIG. 6B . The force of the diaphragm  250  against the mask assembly  277  causes it to deploy. The force of the diaphragm  250  against the mask assembly  277  provides for deployment of the mask assembly  277  regardless of the location of the cartridge  253  which may include overhead in the ceiling of the aircraft, in the sidewalls of the aircraft, or in the seat assembly. 
     In  FIG. 7 , an alternate embodiment of the cartridge is shown. Cartridge  300  has side walls  303  and an end wall  309 . The end wall  309  may be provided with studs  312  for engaging with support structure on oxygen manifold  308  ( FIGS. 8-9 ) as described above in connection with studs  209 . Also, a central opening  310  is surrounded by an adapter  315  having an O-ring  318  disposed thereon. The adapter  315  may be inserted into the oxygen manifold  308  such that a seal is formed by the O-ring  318 . 
     A spring  321  is seated in a retaining member  323 . The retaining member  323  may be provided with a major portion having an H-shape in cross-section. The top section  324  holds the spring  321  and prevents it from making contact with the coiled breathing conduit  327 . A tube  330  extends between the adapter  315  and the breathing conduit  327  and is disposed through an opening in the center of the retaining member  323 . The bottom of the retaining member  323  is hollow and provides additional support for the coiled breathing conduit  327 . The top of the retaining member  323  is provided with a flange  333  that extends outwardly. The spring  321  is compressed between the end wall  309  of the cartridge  300  and the dividing wall  336  in the retaining member  323 . The spring  321  is biased against the retaining member  323  in the downward direction with respect to the orientation of  FIG. 7 . 
     A latch  350  connected to retaining member  323  holds the spring  321  in the compressed state as shown in  FIG. 7 . As shown in  FIGS. 8-9 , the latch  350  is engaged with a surface on the oxygen manifold  308 . A solenoid actuated piston  360  ( FIGS. 8-9 ) may be provided to disengage the latch for deployment of the masks. The piston on the solenoid disengages the latch such that the spring is allowed to expand and push into the mask assembly which in turn pushes against the cover  365  to open the end of the cartridge  300 . After the cover  365  is released, the mask assembly exits from the cartridge  300 . 
     Turning to  FIGS. 10-12 , an alternate embodiment of the invention provides for mounting the springs external to the cartridge. As shown in  FIG. 10 , manifold  400  supports a pair of latches having a catch member  403 , a shaft  406 , a head  409  and a pair of springs  412 . The springs  412  are pre-loaded in compression between the head  409  and the bottom surface  415  of the manifold  400 . 
     As shown in  FIG. 11 , a cartridge  420  has a pair of openings  423  in the top wall for receiving the springs  412  and their supporting structure. The cartridge  420  may be provided with studs  413  for mounting the cartridge  420  on the manifold  400 . The cartridge  420  also includes a central opening  426  surrounded by an adapter  429 . The central opening is in fluid communication with a breathing conduit  432  connected to an oronasal mask assembly. Accordingly, oxygen from the manifold  400  can flow into the breathing conduit  432  when the cartridge  420  is attached to the manifold  400 . A spacer member  430  is disposed between the springs  412  and the mask assembly. 
     Turning to  FIG. 12 , a solenoid actuated piston assembly  450  is mounted on the manifold  400  and is disposed such that the pistons disengage the catch members  403  from the oxygen manifold  400 . Once the catch members  403  are free, the springs  412  push against the spacer member  430  which pushes the mask assembly against the cover  480  and out of the cartridge  420 . 
     It is to be understood that the present invention may be used with all types of aircraft supplemental oxygen delivery systems. There are two primary types of delivery systems: systems whose deployment is initiated by the turning on of a central oxygen supply and systems whose deployment is initiated by an electrical signal. In systems where deployment is initiated by turning on a central oxygen supply, the pneumatic pressure can be used to push the mask out of its container as described above. Because the containers are normally stored in a housing that typically includes a cover, the pneumatic pressure of the oxygen can be used to unlatch the cover or the cover could be unlatched by the masks pressing against the inside of the cover as they are ejected from their containers. 
     There are also systems where deployment is initiated by the turning on of a central oxygen supply; however, in order to conserve oxygen the central oxygen supply is not delivered to the individual masks until users reach for the mask and take an action such as drawing the mask to their face. In this situation, the pressure of the oxygen supply being turned on may be used to open the door of the housing and to provide flow to a bellows or bladder for ejecting the mask. Returning to  FIGS. 6C-6E , a valve may be inserted in the oxygen supply to prevent a sustained flow of oxygen out through a mask which is not being used. In  FIG. 6C , such an arrangement is shown where the valve  285  is inserted at the point where the hose assembly  280  attaches to a fitting  283  on diaphragm  250 . In this case, the valve  285  may be a simple on/off toggle valve or a clip closing off hose assembly  280 . This valve may be attached to a lanyard  288  and when mask assembly  277  is pulled to a user&#39;s face, the lanyard  288  will actuate the valve  285  or release the clip allowing oxygen to flow. The valve could also be electronic such that it would be activated by the user&#39;s drawing in a breath after donning the mask and creating a slight negative pressure in the mask and tubing, which would be sensed by the electronic switch allowing the oxygen to flow. 
       FIG. 6D  illustrates a switch that may be mounted on the manifold or the cartridge. Oxygen flows into a bellows or bladder ejecting the mask as described previously but cannot flow into the tubing of the mask until the electronic valve  289  senses the presence of a user and allows the oxygen to flow to the mask assembly  277 . 
       FIG. 6E  is a variation of the electronic switch located in the oxygen supply. In this example, the electronic switch  296  allows oxygen to flow into the bellows or bladder through central opening  268 , ejecting the mask assembly  277  as described previously. However, the switch  296  is programmed to allow the flow of oxygen to occur for only the length of time needed to eject the mask, after which the oxygen supply is cut off by the electronic switch  296 . The electronic switch  296  does not reopen, allowing the flow to continue, until it senses by means of sensor tube  294  that the user is taking a breath. 
     In systems where deployment of the masks is initiated by an electrical signal, without any flow of oxygen occurring, the oxygen source is often a chemical oxygen generator or a sealed oxygen cylinder serving only the group of masks contained in one or more housings. In such cases in order not to expend an oxygen generator or unseal a sealed cylinder, the oxygen supply may be initiated by the users reaching for the oxygen masks and pulling them toward their faces. Accordingly, the ejection of the masks is not associated with the flow of oxygen as the masks have to be ejected prior to actuation of the source of oxygen gas. 
       FIG. 13  depicts an embodiment of the aforementioned system  700  wherein the oxygen source  702 , which may be, for example, but not limited to, a chemical oxygen generator, serves only the group of masks contained in one housing (it should be understood that there may be only one mask in the housing). In system  700 , the oxygen source  702  is attached to the housing. In other embodiments, the oxygen source  702  may be located at some distance from the housing. The system  700  may include an igniter  704 . As described above, the system  700  may be initiated in various ways. For example, ejection of the masks may be caused by the flow of oxygen from the oxygen source  702 . In another example, ejection of the masks may be caused by another mechanism such as the spring-biased ejector, and the flow of oxygen may be initiated by the users pulling the oxygen masks towards their faces. Some embodiments of system  700  further comprise an enclosure  706  containing all components of the system  700  including the oxygen source  702 . 
     Although the present invention has been described with respect to one or more particular embodiments, it will be understood that other embodiments of the present invention may be made without departing from the spirit and scope of the present invention. Hence, the present invention is deemed limited only by the appended claims and the reasonable interpretation thereof.