Abstract:
A self-contained breathing apparatus (SCBA) comprising: a mouthpiece; a breathing component; and a safety quick disconnect comprising: a valve body; a valve spool comprising an L-shaped channel formed such that when the valve spool is appropriately rotated, the L-shaped channel (i) places an opening of the valve body in communication with a first port, or (ii) places the opening in communication with a second port; and a lock mechanism for (i) preventing the valve spool from rotating unless the breathing component is positioned in one of first and second mounts formed on the valve body adjacent the first and second ports, and a replacement breathing component is positioned in the other of the first and second mounts, and (ii) preventing the removal of a breathing component from a mount adjacent to a port which is in communication with the opening.

Description:
REFERENCE TO PENDING PRIOR PATENT APPLICATIONS 
       [0001]    This patent application claims benefit of: 
         [0002]    (i) pending prior U.S. Provisional Patent Application Ser. No. 60/878,338, filed Jan. 3, 2007 by Paul A. Chambers for SELF CONTAINED SELF RESCUER—PLUS (Attorney&#39;s Docket No. CHAMB-11 PROV); 
         [0003]    (ii) pending prior U.S. Provisional Patent Application Ser. No. 60/925,314, filed Apr. 19, 2007 by Paul A. Chambers for SELF CONTAINED SELF RESCUER—PLUS (Attorney&#39;s Docket No. CHAMB-12 PROV); and 
         [0004]    (iii) pending prior U.S. Provisional Patent Application Ser. No. 60/965,464, filed Aug. 20, 2007 by Paul A. Chambers for UNIVERSAL MINER SELF RESCUER (UMSR) (Attorney&#39;s Docket No. CHAMB-13 PROV). 
         [0005]    The three above-identified patent applications are hereby incorporated herein by reference. 
         [0006]    C. 
     
    
     FIELD OF THE INVENTION 
       [0007]    This invention relates to self-contained breathing apparatuses (SCBAs) in general, and more particularly to a self-contained breathing apparatus with a safety quick disconnect for permitting safe and ready access to a replacement breathing component. 
       BACKGROUND OF THE INVENTION 
       [0008]    The nature of underground mining operations makes them highly dangerous. 
         [0009]    For example, in the case of a mine collapse, the supply of breathable air can be severely compromised, placing the miners in great danger. 
         [0010]    Furthermore, mines are often highly susceptible to the infusion of noxious gases (e.g., methane, carbon monoxide, etc.). This situation can occur in many scenarios, even where there is no catastrophic mine collapse. Gas pockets can be exposed at any time and without notice, and can be life-threatening even where the mine is structurally intact. In any of these situations, once the gas enters the space occupied by the miners, their lives are in serious danger. 
         [0011]    In all of these situations, the miners must quickly recognize the danger and then must obtain an supply of breathable air. This supply of breathable air may be provided by various means, e.g., a filtered system, a conventional “open-loop” self-contained breathing apparatus (SCBA), a conventional “closed-loop” self-contained breathing apparatus (SCBA), a solid state oxygen generator, etc. The equipment for providing the supply of breathable air is commonly referred to as a Self Rescuer and is generally carried by the miners on their belts. Once the miners have “switched over” to this supply of breathable air, they must then escape the danger zone. In the case of a “benign” gas pocket, escape may be as simple as walking or riding a mine car out of the affected area. In the case of a mine collapse, gas explosion, or other serious event, escape may involve crawling, tunneling, walking or just waiting for rescue. In any of these latter situations, there is a significant danger that the supply of breathable air may be depleted before the miner has reached a safe location. 
         [0012]    At the same time, in many of these situations, it is not possible for the miners to use conventional negative pressure filtered respirators, powered air purifying respirator (PAPR), etc. due to the nature of the threat, e.g., the possible air contaminants (e.g., some gases), the physical state of the ambient air (e.g., super-heated air), etc. In these situations, a self-contained breathing apparatus (SCBA) is required. 
         [0013]    Conventional “open-loop” SCBA units generally consist of a tank of compressed gas (usually ambient, but filtered, air) with the flow controlled by a regulator or demand valve. One of the major inefficiencies of these units is that the exhausted and/or exhaled air (still containing significant usable oxygen) is vented to the environment and thus lost to the user. Much greater efficiencies (translating into smaller, lighter units and longer supply times) can be attained by using “closed loop” SCBA units which recycle the exhaust air and recover the oxygen, and/or remove the undesirable products of respiration (mainly carbon dioxide). A device utilizing this approach is commonly referred as a “Rebreather”. See  FIG. 1 . 
         [0014]    Any respirator device, whether filtered, open-loop SCBA, closed-loop SCBA, etc. has a limited capacity to supply breathable air. If the miners exhaust the capacity of the respirator device while still in a dangerous environment, the miners must be able to access a replacement breathing component and make the “change-over” to the replacement breathing component without “breaking the seal” or otherwise exposing themselves to breathing in the potentially noxious gases. 
         [0015]    As a result, a primary object of the present invention is to provide a self-contained breathing apparatus (SCBA) which is able to safely and quickly connect to a replacement breathing component without “breaking the seal” so that the replacement breathing component can supply additional breathing capacity to the user. Preferably, the replacement breathing component can take any number of forms, e.g., the working portion of another “closed-loop” SCBA, an air bottle, a carbon monoxide filter respirator, etc. 
       SUMMARY OF THE INVENTION 
       [0016]    The present invention provides a self-contained breathing apparatus (SCBA) which is able to safely and quickly connect to a replacement breathing component without “breaking the seal” so that the replacement breathing component can supply additional breathing capacity to the user. 
         [0017]    In one form of the present invention, there is provided a self-contained breathing apparatus (SCBA) comprising: 
         [0018]    a mouthpiece; 
         [0019]    a breathing component for providing breathable air, the breathing component comprising a component interface; and 
         [0020]    a safety quick disconnect comprising:
       a valve body defining:
           an internal chamber;   an opening communicating with the internal chamber and connectable with the mouthpiece;   first and second ports communicating with the internal chamber;   first and second mounts formed on the body adjacent to the first and second ports, respectively, for receiving the component interface of the breathing component, the first and second mounts being configured so as to place the breathing component into communication with the internal chamber when the component interface is in engagement with one or the other of the first and second mounts;   
           a valve spool selectively rotatably disposed within the internal chamber, wherein the valve spool comprises an L-shaped channel formed such that when the valve spool is appropriately rotated, the L-shaped channel (i) places the opening in communication with the first port, or (ii) places the opening in communication with the second port; and   a lock mechanism for (i) preventing the valve spool from being rotated unless the component interface of the breathing component is positioned in one of the first and second mounts and a component interface of a replacement breathing component is positioned in the other of the first and second mounts, and (ii) preventing the removal of a component interface from a mount adjacent to a port which is in communication with the opening.       
 
         [0028]    In another form of the present invention, there is provided a self-contained breathing apparatus (SCBA) comprising: 
         [0029]    a mouthpiece; 
         [0030]    a counterlung; and 
         [0031]    a breathing component interposed between the mouthpiece and the counterlung, the breathing component being adapted to provide breathable air; wherein the counterlung is sized so as to have a volume which is approximately equal to the tidal volume of a pair of adult lungs. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]    These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which are to be considered together with the accompanying drawings wherein like numbers refer to like elements and further wherein: 
           [0033]      FIG. 1  is a schematic view showing a prior art SCBA; 
           [0034]      FIG. 2  is a schematic diagram showing a high-level overview of a novel SCBA formed in accordance with the present invention; 
           [0035]      FIG. 3  is a schematic diagram showing a more detailed illustration of a novel SCBA formed in accordance with the present invention; 
           [0036]      FIG. 4  is a schematic view showing a novel breathing component formed in accordance with the present invention; 
           [0037]      FIGS. 5-11  are schematic views showing a novel safety quick disconnect of the present invention; 
           [0038]      FIGS. 12-14  are schematic views illustrating how a breathing component and a replacement breathing component may be simultaneously connected to the safety quick disconnect, with only one breathing component being operable at a given time; 
           [0039]      FIGS. 15-17  are schematic views showing how a depleted breathing component may be “switched out” (i.e., changed over) to a replacement breathing component; 
           [0040]      FIGS. 18-23  are schematic views illustrating various configurations for a novel breathing component formed in accordance with the present invention; and 
           [0041]      FIGS. 24-27  are schematic views illustrating various types of breathing components which can be connected to the safety quick disconnect. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0042]    Looking next at  FIGS. 2 and 3 , there is shown a novel self-contained breathing apparatus (SCBA)  5  formed in accordance with the present invention. SCBA  5  generally comprises a mouthpiece  10  which is releasably connected to a multi-port safety quick disconnect  15 . Also connected to quick disconnect  15  is a breathing component  20 . A replacement breathing component  20 A may also be connected to quick disconnect  15  when breathing component  20  is to be replaced. 
         [0043]    Looking now at  FIGS. 2-4 , breathing component  20  preferably comprises a demand regulator  25 , a carbon dioxide scrubber  30  and a counterlung  35 . Breathing component  20  also comprises an oxygen supply  40 . 
         [0044]    During use, the user places mouthpiece  10  in their mouth and inhales and exhales through their mouth (a noseclip may also be supplied to restrict breathing through the nose and permit breathing through only the mouth). As air is exhaled, it passes through demand regulator  25 , through carbon dioxide scrubber  30  and fills counterlung  35 . As this occurs, carbon dioxide scrubber  30  purges carbon dioxide from the exhaled air. Conversely, as air is inhaled, air is drawn from counterlung  35 , through carbon dioxide scrubber  30 , through demand regulator  25  and back into the lungs of the user. Again, as the air from counterlung  35  passes through carbon dioxide scrubber  30 , the scrubber purges carbon dioxide from the air. 
         [0045]    Demand regulator  25  monitors the air pressure in the system and, when the air pressure falls below a certain threshold, releases supplemental oxygen from oxygen supply  40 . More particularly, as the user breathes, the body metabolizes oxygen and releases carbon dioxide. This carbon dioxide is then removed from the system by carbon dioxide scrubber  30 . Therefore, in a “closed-loop” system, as the user breathes, oxygen is consumed by the user, carbon dioxide is consumed by the scrubber, and the quantity of air is reduced. To that end, demand regulator  25  monitors the air pressure in the system and, as the quantity of air is reduced during breathing and scrubbing (which also reflects a reduction in the quantity of oxygen available for breathing), demand regulator  25  releases supplemental oxygen to the system to compensate for the consumed gases. 
         [0046]    As a result of this construction, breathing component  20  is designed to provide extended breathing capacity, due to the use of (i) carbon dioxide scrubber  30 , which allows the re-breathing of exhaled air, and (ii) demand regulator  25  and oxygen supply  40 , which supply supplemental oxygen to the system as oxygen is consumed through breathing. 
         [0047]    Significantly, counterlung  35  is carefully configured so as to have a size approximately equal to tidal volume of a pair of human lungs. This is approximately three times smaller than traditional counterlungs. By configuring counterlung  35  with this unique size, breathing component  20  ensures that demand regulator  25  will release fresh oxygen to the system before the oxygen content of the air being re-breathed falls to a level which is too low to safely sustain the user. More particularly, with each breath of the user, approximately 20% of the oxygen inhaled is consumed by the body and is replaced with exhaled carbon dioxide. This exhaled carbon dioxide is in turn purged by carbon dioxide scrubber  30 . Thus, in the absence of a supplemental oxygen source, as the user breathes, the total quantity of air will continuously decrease as the carbon dioxide is pulled from the air. If counterlung  35  is made too large, it will take too long for the quantity of air in the system to be depleted to the point where demand regulator  25  will trigger the release of supplemental. oxygen from oxygen supply  40 . On the other hand, if counterlung  35  is formed too small, a user will not be able to inhale and exhale a full breath, which is important in emergency breathing situations where the user may need to be moving about rapidly. Sizing counterlung  35  so as to be the approximately the size of the tidal volume of a pair of lungs is a new and significant advance in the art. 
         [0048]    In another significant advance over the prior art, SCBA  5  utilizes a multi-port safety quick disconnect  15  to permit replacement breathing component  20 A to be safely and quickly connected to mouthpiece  10  without “breaking the seal”, so that additional breathing capacity can be safely supplied to the user when necessary. More particularly, any breathing component (e.g., a “closed-loop” SCBA system, a carbon dioxide absorber, an oxygen tank, etc.) has a finite functional lifetime: at the end of that functional lifetime, the breathing component must ultimately be replaced with a fresh unit in order to sustain a user. The present invention provides novel multi-port safety quick disconnect  15  to permit replacement breathing component  20 A to be safely and quickly connected to mouthpiece  10  without “breaking the seal”, so that additional breathing capacity can be safely supplied to the user when necessary 
         [0049]    Safety disconnect  15  is shown in greater detail in  FIGS. 5-11 . Safety disconnect  15  generally comprises a hollow rectangular valve body  45  having a top opening  48  for connecting to mouthpiece  10 , two faces  50 ,  55  ( FIGS. 6 and 9 ) with ports  60 ,  65  formed therein, respectively, and a back plate  67  for closing off valve body  45 . The faces  50 ,  55  are each configured with a U-shaped rail  70  for slidably receiving, and forming an airtight seal with, a component interface  75  which connects with a breathing component. A cylindrical valve spool  80 , with an L-shaped channel  85  formed therein, is rotatably disposed within valve body  45 . A selection knob  90  is provided to permit the user to adjust the rotational position of valve spool  80  within valve body  45 . As a result of this construction, L-shaped channel  85  can be used to connect port  60  with opening  48  or, alternatively, port  65  with opening  48 . 
         [0050]    Significantly, means are provided for restricting the position of valve spool  80  within valve body  45 , and for restricting the inadvertent removal of a component interface  75  from valve body  45 , whereby to present a user from accidentally breathing ambient air. 
         [0051]    More particularly, back plate  67  includes a locking clip  95  having a pair of projecting spring fingers  100 . Valve spool  80  includes four recesses  105  formed therein for selectively receiving spring fingers  100  of locking clip  95 . As a result of this construction, valve spool  80  may not be rotated within valve body  45  unless, and until, two component interfaces  75  are pressed sufficiently rearwardly within U-shaped rail  70  as to push the two corresponding projecting spring fingers  100  out of their corresponding spool recesses  105 . 
         [0052]    Furthermore, selection knob  90  is provided with a peripheral extension  110  along a portion of its perimeter which prevents accidental removal of the component interface  75  selected by and in use on that corresponding side of the valve body so as to prevent the user accidentally disconnecting the active breathing air supply and exposing the corresponding port  60 ,  65  to atmosphere. 
         [0053]    In addition to the foregoing, valve spool  80  is formed so that when it is in a locked position (i.e., so that a spring finger  100  is received in a spool recess  105 ), L-shaped channel  85  is connecting either port  60  with opening  48  or port  65  with opening  48 . 
         [0054]    As a result of this construction, a component interface  75  may only be withdrawn when another component interface  75  has been connected to quick disconnect  15  and valve knob  90  has been rotated to select the side being retained as a breathing source. Furthermore, as shown in  FIGS. 12-14 , only one port  60 ,  65  may be open at any given time to mouthpiece  10 . Thus, the mouthpiece can never be opened to ambient air. As a result, multi-port safety quick disconnect  15  permits a replacement breathing component to be safely and quickly connected to mouthpiece  10  without “breaking the seal”, so that additional breathing capacity can be safely supplied to the user. In other words, a user cannot disconnect from a current breathing component unless, and until, a replacement breathing component has been properly connected to multi-port quick disconnect  15 . Thus, the construction quick disconnect  15  prohibits a user from (i) accidentally disengaging a current breathing component until a replacement breathing component has been connected, and (ii) inadvertently connecting the mouthpiece to ambient air. 
         [0055]    In other words, the foregoing construction permits a first breathing component is to be safely and readily replaced with a replacement breathing component when necessary. More particularly, and looking now at  FIGS. 15-18 , safety quick disconnect  15  permits a first breathing component  20  to be replaced with a replacement breathing component  20 A, and the first breathing component  20  to be thereafter discarded. 
         [0056]    Looking next at  FIGS. 18-21 , it will be seen that quick disconnect  15  can be rotatably positioned in a variety of a configurations vis-à-vis breathing component  20  so as to provide a desired profile, e.g., so as to facilitate wearing on a belt, attachment to alternative breathing component, etc. Furthermore, breathing component  20  can have an ergonomic exterior shape so as to facilitate wearing it on a belt, e.g., the body of breathing component  20  can have a kidney-shaped cross-section and counterlung  35  can have a flat shape (when empty), etc. See, for example,  FIG. 22 . 
         [0057]    If desired, and as shown in  FIGS. 23 and 24 , quick disconnect  15  can be use to switch off between two identical breathing components  20 ,  20 A. Alternatively, quick disconnect  15  can be connected to various other types of breathing components of the sort well known in the art, e.g., a carbon monoxide absorber  20 B ( FIG. 25 ), an oxygen bottle  20 C ( FIG. 26 ), etc. See also  FIG. 27 . 
       MODIFICATIONS 
       [0058]    While the present invention has been described in terms of certain exemplary preferred embodiments, it will be readily understood and appreciated by those skilled in the art that it is not so limited, and that many additions, deletions and modifications may be made to the preferred embodiments discussed herein without departing from the scope of the invention.