Abstract:
A valve manifold assembly having a valve body with at least one chamber defined therein. The chamber has at least one inlet and at least one outlet and has at least one opening. A poppet is disposed in the chamber. The poppet slides in the chamber between a first position where the poppet seals the inlet and a second position where the poppet is disposed in spaced-apart relation relative to the inlet. The poppet has an opening disposed therein. A pin having a first section with a first diameter and having a second section with a second diameter is capable of being slidably disposed through the at least one opening in the valve body and through the opening in the poppet.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   Applicant hereby claims priority based on U.S. Provisional Patent Application No. 60/346,397 filed Jan. 7, 2002, entitled “Valve Manifold Assembly” which is incorporated herein by reference. 

   FIELD OF THE INVENTION 
   The invention relates to an assembly for deploying an emergency breathing mask in an aircraft. 
   BACKGROUND OF THE INVENTION 
   Many aircraft are required to provide passengers and crew members in the pressurized cabin with an emergency breathing mask in the event of a sudden loss of cabin pressure due to a rupture in the cabin wall or to a failure in the aircraft&#39;s pressurizing system. The conventional emergency breathing mask is typically stowed in an overhead storage container directly over the user. Upon a sudden loss of cabin pressure, the container door automatically opens and the mask is deployed by gravity to the user. The mask typically hangs from the open container in the vicinity of the user, but the flow of breathing gas to the mask is not automatically activated. Because the mask may drop over an empty seat, it is desirable to have a user-activated valve that controls the flow of breathing gas to the mask. It has been known to provide a lanyard that is connected between the breathing gas conduit or the mask and a valve in the container such that when the mask is pulled toward the face of the user, the tension on the lanyard opens a valve to allow breathing gas to flow to the mask. An example is disclosed in U.S. Pat. No. 4,909,247 which is incorporated herein by reference. 
   What is needed is an improved valve manifold assembly. 
   SUMMARY OF THE INVENTION 
   The present invention meets the above need by providing a valve manifold assembly having a valve body with at least one chamber defined therein. The chamber has at least one inlet and at least one outlet and has at least one opening. A poppet is disposed in the chamber. The poppet slides in the chamber between a first position where the poppet seals the inlet and a second position where the poppet is disposed in spaced-apart relation relative to the inlet. The poppet has a bore disposed therethrough. A pin is capable of being slidably disposed through the at least one opening in the valve body and through the bore in the poppet. The pin may take different shapes to avoid unintentional actuation of the valve due to environmental conditions such as shock or vibration. In a first embodiment, the pin has at least two concentric sections having different diameters. In a second embodiment, the pin is elongated such that it is prevented from exiting the poppet due to the position of the door when the door is in the closed position. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is illustrated in the drawings in which like reference characters designate the same or similar parts throughout the figures of which: 
       FIG. 1  is a fragmentary longitudinal schematic view of the interior of an airplane showing one environment in which the invention is operative; 
       FIG. 2  is a partial front elevational view of an aircraft passenger oxygen system in the deployed position; 
       FIG. 3  is a top view of the valve manifold assembly of the present invention; 
       FIG. 4  is a cross-sectional view taken along lines  4 — 4  of  FIG. 3 ; 
       FIG. 5  is a cross-sectional view taken along lines  5 — 5  of  FIG. 4 ; 
       FIG. 6  is a side elevational view of the pin of the present invention; 
       FIG. 7  is an end view taken along lines  7 — 7  of  FIG. 6 ; and, 
       FIG. 8  is a sectional view of an alternate embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
   In an embodiment of the invention chosen for the purpose of illustration there is shown by way of example a fragment of aircraft frame  10  having a floor  11  on which are rows of seats  12  and  13 . A ceiling panel  14  has mounted in it over each respective row of seats an oxygen mask dispensing container indicated generally by the reference character  15 , all of which are supplied from a common oxygen source  16  through an oxygen line  17  having a pressure control valve  18 . By way of example, the passenger mask unit on the left is shown in released position and that on the right in closed position. Each mask  21  is provided with a conduit  24  for oxygen attached to a valve manifold assembly  30  ( FIGS. 3-5 ) and a lanyard  33 . 
   Turning to  FIG. 2 , as an example two masks  21  are shown in the deployed position. The number of masks  21  may be varied as will become obvious to those of ordinary skill in the art. As shown a door  22  opens from ceiling panel  14  to deploy the masks  21 . As described in greater detail hereinafter, the door  22  may be automatically opened by means of a spring-biased piston  23  ( FIG. 4 ) engaging with a latch  26  on the inside surface of the door  22 . The masks  21  are shown in a fully downwardly deployed position within reach of the user. When the door  22  is opened as shown in  FIG. 2 , the free fall of the masks  21  is stopped by lanyards  33  which connect between the conduit  24  at  36  and control pins  39  ( FIG. 4 ) on valve manifold assembly  30 . The lanyards  33  may be attached at one end to the conduit  24  as shown or they can be attached at other points on the conduit  24  or mask  21 . The lanyards  33  can be attached at any point on the conduit  24  or mask  21  that provides significant motion when the mask  21  is drawn to the face of the user during deployment. The lanyards  33  are connected to pins  39  by eyelets  42  ( FIG. 4 ) that are attached to the pin  39  through opening  32  (FIG.  6 ). Lanyards  33  thus support masks  21  within reach of intended users and in this position hang taut under the weight of the masks  21  while conduits  24  remain slack as illustrated at  45  in FIG.  2 . Traction on lanyard  33 , as by positive action of an individual user pulling downward on one of the masks  21 , withdraws pin  39  from valve manifold assembly  30  to actuate the supply of breathing gas to that mask  21 . In the illustrated form, each mask  21  is of the modified phase dilution type comprising a truncated hollow cone  31  of suitable material, such as an elastomer, open through its larger end which is adapted to be held against the face of a user and kept in place by an elastic band  34 . The smaller end  35  of each mask  21  is connected to a reservoir bag  37  which is connected to conduit  24  whereby breathing fluid is provided through conduit  24  into the bag to accumulate flow when the user is not inhaling. Attached at the smaller end  35  of the mask  21  are three flapper valves (not shown). One flapper valve is spring loaded to be a phase dilution valve which allows a predetermined amount of outside air into the mask  21  to mix with the breathing fluid supplied to the user so that each user will receive a metered amount of fluid. Another flapper valve is an exhalation valve assembly through which the exhaled carbon dioxide from the user is dispensed to the surrounding atmosphere. The third flapper valve permits fluid flow from the reservoir bag  37  to mask  21  and closes to prevent reverse flow. Such mask arrangements are known in the art, and are not per se, a part of this invention. Other face masks  21 , including masks equipped with demand regulators can be utilized in the present invention. 
   Turning to  FIG. 3 , the valve manifold assembly  30  has a set of openings  50  disposed in the top of the assembly  30 . The openings  50  may be threaded to engage with a set of fasteners  52  (shown in  FIG. 4 ) that attach the assembly  30  to the oxygen mask dispensing container  15 . Hose connectors  56  extend from opposite sides of the assembly  30 . The connectors  56  shown are in the form of hose barbs  55  for connection to the conduits  24  that carry the breathing gas to the masks  21 . Other types and shapes of hose connectors would also be suitable. For example, as will be evident to those of ordinary skill in the art, additional hose connectors  56  may be connected to the flow actuation valve  60  so that a single flow actuation valve can distribute breathing gas to a plurality of masks  21  through a plurality of conduits  24 . As will also be evident to those of ordinary skill in the art, if multiple masks  21  are supplied through a single flow actuation valve then the respective lanyards  33  would each be connected to a single pin  39 . Accordingly, the present invention may function with a flow actuation valve for every mask or may function with multiple masks connected to a single flow actuation valve. When multiple masks  21  are connected to a single flow actuation valve, breathing gas may be allowed to flow to a mask deployed over an empty seat. 
   As will be described in greater detail hereinafter, the valve manifold assembly  30  is formed by attaching valve housings  100  to opposite sides of valve body  71  by means of screws  401 . The valve housing  100  has a slot  300  that allows for rotation of the pin  39  in unison with the poppet  70 . The opening  57  in the poppet  70  that receives the pin  39  visible through the slot  300 . 
   In  FIG. 4 , the lanyards  33  are connected to pins  39  by eyelets  42 . On the left hand side of the figure, a first flow actuation valve  60  is shown in the closed position. On the right hand side of the figure a second flow actuation valve  63  (which is identical to the first flow actuation valve  60 ) is shown in the open position where the pin  39  has been removed by the user pulled lanyard  33 . A pair of ports  66  (best shown in  FIG. 5 ) provide for pressurizing the manifold from the breathing gas source. Two ports  66  are provided in the manifold, therefore numerous manifold assemblies  30  can be connected in series so that outlets  56  are in parallel to accommodate specific applications. Multiple assemblies  30  may be connected in series or a single assembly  30  may be constructed with additional flow actuation valves. One manifold port  66  can be plugged while the other is supplied with gas under pressure. 
   The flow actuation valve  60  is comprised of a precision machined poppet  70  that may be constructed out of suitable materials such as aluminum. The poppet  70  moves back and forth inside a chamber  73  disposed inside the valve body  71 . A set of O-rings  74  seals the sides of the poppet  70  inside the chamber  73  so that breathing gas cannot flow around the sides of the poppet  70 . At one end of the poppet  70 , a soft elastomer seat  76  is inserted into a bore in the poppet  70  and retained in place with an adhesive. The bore is deep enough to provide a sufficient amount of space for the elastomer as described hereafter. The soft elastomer may comprise a silicone meeting or exceeding MIL ZZ-R-765 Type IIA or IIB Grade  70 . The adhesive may comprise a cyanoacrylate, silicone, or other suitable adhesive. A hard seat  79  is formed around a centrally disposed opening  82  in the valve body  71 . 
   A coil spring  85  has a first end  88  and a second end  91 . The first end  88  engages with the valve body  71  around the opening  82 . The second end  91  is disposed opposite the first end  88  and rests inside an opening  94  in the poppet  70 . Depending on the spring rate, the spring  85  could also be disposed external to the poppet  70 . The spring  85  may be formed out of stainless steel. The spring  85  biases the poppet in the open position shown on the right hand side of FIG.  4 . 
   In order to assemble the flow actuation valve  60 ,  63 , the valve spring  85  is inserted into the chamber  73  formed in the valve body  71  such that the poppet  70  acts to compress the spring  85  as it is inserted. The portion of the poppet  70  extending beyond the valve body  71  is inserted into the valve housing  100 . The valve housing  100  is secured to the valve body  71  using screws  401  ( FIG. 5 ) to form the valve manifold assembly  30 . 
   Upon inserting the pin  39  through the poppet  70 , the poppet  70  and the soft seat  76  are forced toward the hard seat  79  while compressing the valve spring  85 . At full insertion of the pin  39 , the compression forces the soft seat  76  to conform to the hard seat  79  thereby providing a seal. Also, when the pin  39  is inserted into the poppet  70  as shown in the left hand side of  FIG. 4 , force is exerted by the spring  85  onto the pin  39  through the poppet  70  causing it to rest against the valve housing  100 . 
   In the middle of  FIG. 4 , a spring-biased piston  23  is shown. The spring  95  may be a coil spring disposed around the piston  23  and biased in the closed position as shown in FIG.  4 . The piston  23  is held inside a housing  96  that attaches to the assembly  30 . The piston  23  has a set of O-rings  97  for sealing the piston inside the housing  96 . The inside of piston  23  is hollow such that a pressurized breathing gas from port  66  acts against the inside surface  98  of the piston  23  to move the piston  23  downward, with respect to the orientation of  FIG. 4 , against the force of spring  95 . When actuated by pressure, the piston  23  extends out of the opening  99  in the housing  96  and engages with the door latch  26  to release the door  22  as shown in FIG.  2 . 
   Turning to  FIG. 5 , the arrows  101  indicate the flow path of the breathing gas through the right hand side of the figure. The removal of the pin  39  results in the poppet  70  moving to the right with respect to the orientation of the figure. The force of the spring  85  (and supplemented by the gas pressure) causes this movement of the poppet  70 . As a result of this motion, the soft seat  76  on the poppet  70  moves away from the central opening  82  in the valve body  71 . Accordingly, referring to the right hand side of the figure, the breathing gas from the one or more open ports  66  is allowed to pass through the central opening  82  and into the chamber  73  formed between the left side of the poppet  70  and the inside walls  102  of the valve body  71 . Because the poppet  70  has O-rings  74  installed around its perimeter, the breathing gas cannot escape between the inside walls  102  of the valve body  71  and the poppet  70 . A pair of pathways  103  disposed through the poppet  70  provide for egress of the pressurized gases. As shown, there are two channels disposed through the poppet  70 . Each channel has a first open end on the left side of the poppet  70  and has a second open end at the right hand side of the poppet  70 . The second opening allows breathing gas under pressure to pass through the poppet  70  into the chamber  110  formed between the poppet  70  and the valve housing  100 . The valve housing  100  also has a central opening  112  that extends through the hose connector  56 . The breathing conduit  24  that leads to the mask  21  is attached to the hose connector  56  and carries the breathing gas to the mask  21  as shown in FIG.  2 . Returning to  FIG. 5 , a calibrated orifice  113  is fabricated in the hose barb area of the connector  56  of the valve housing  100 , so that a predetermined flow of oxygen is administered to the oxygen mask  21  at a given supply pressure. 
   In  FIGS. 6 and 7 , the pin  39  is shown in greater detail. The pin  39  has two sections with different but concentric diameters. The first diameter  200  which is the larger of the two diameters is located along a midportion  210  of the pin  39 , while the second diameter  220  which is the smaller of the two diameters extends along end portions  215  disposed on opposite sides of the mid portion  210 . A transition zone  225  of varying diameter is located at both locations where the pin  39  changes diameters. When the pin  39  is fully inserted, the section having the first diameter  200  is acted on by the compressed valve spring  85  through the poppet  70 , thereby causing the section with the smaller pin diameter  220  to rest against the opening in the valve housing  100 . When the pin  39  is removed in the direction indicated by arrow  240  in FIG.  4  and with reference to the opening in the valve housing  100  located closer to the eyelet  42 , the section with the smaller diameter  220  passes against the valve housing  100  until the first transition zone  225  of varying diameter comes in contact with the valve housing  100 . As the transition zone  225  of the pin  39  passes through the opening in the valve housing  100 , the valve spring  85  is further compressed through the force of the pin  39  on the poppet  70 . The valve spring  85  compression continues until it reaches the maximum that is defined as one-half of the diametrical difference between the two diameters  200 ,  220  of the pin  39 . This additional compression of the valve spring  85  increases the amount of force required to remove the pin  39 . The additional force required to remove the pin  39  is provided to prevent pin  39  from being inadvertently removed due to environmental conditions such as shock and vibration. The soft seat  79  material must be sufficiently resilient to maintain a seal at both levels of compression forces corresponding to the different diameters  200 ,  220  and to do so without resulting in compression set. The depth of the bore may be increased in order to provide for a greater amount of the elastomer to be utilized in order to prevent compression set. 
   In  FIG. 8 , an alternate embodiment of the invention includes a pin  339  having a constant diameter throughout a majority of its length. The pin  339  is elongated such that inadvertent removal of the pin  339  from the poppet  70  is prevented because the pin  339  extends downward far enough toward the door  22  such that the pin  339  is obstructed by the door  22  when the door  22  is in its closed position. When the door  22  opens as shown in  FIG. 2 , the masks  21  drop down and the pin  339  can be removed from the poppet  70  via the user pulled lanyard  33  as described previously. 
   Returning to  FIG. 4 , the pin  39  extends through the poppet  70  and completely through the valve assembly  30 . As will be evident to those of ordinary skill in the art, the poppet  70  may be provided with a recess for receiving a pin that does not extend all the way through the valve assembly  30 . Also, it will be evident to those of ordinary skill in the art that the movable member does not have to be solid and could be hollow. 
   While the invention has been described in connection with certain embodiments related to a passenger oxygen system for aircraft, it is not intended to limit the scope of the invention to the particular forms set forth, but, on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention. In particular, the valve manifold assembly  30  of the present invention may be useful in other shutoff or gas valve applications. Accordingly, the invention is not to be limited to the particular application to a passenger oxygen delivery system in an aircraft. Other applications of the device to shut off valves will be known to those of ordinary skill in the art.