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[0001]    This application claims benefit to U.S. Provisional Application 60/776,954, filed on Feb. 28, 2006, which is herein incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    The invention generally relates to mine safety and more specifically to an emergency safety pod developed for the purpose of sustaining the lives of miners in case of disaster. 
         [0003]    The mining industry is subject to distinct and inherent risk of extremely hazardous and often fatal catastrophes which may occur with little or no warning. Consequently, mining accidents account for thousands of deaths each year, particularly in developing countries. Such accidents vary widely in magnitude and origin, ranging from seismic activity, poisonous gas and ignition of flammable gas, to sudden flooding, dust explosions and collapsing shafts. 
         [0004]    In the face of a sudden, life-threatening emergency, the unfortunate individuals closest to the danger may be unable to reach an exit of the mine or the chamber in time. Accordingly, some mines may include life-saving pods which may be installed within the mine and transported to remain within the vicinity of areas where miners plan to carry out their work. A known life protection enclosure for mines is shown in U.S. Pat. No. 4,815,363 (“the &#39;363 patent”). The enclosure of the &#39;363 patent, however, is lacking in several respects. For example, the &#39;363 patent does not provide means for monitoring interior and exterior atmospheric conditions, does not include a system for maintaining a positive interior air pressure, nor does it include a equipment for aiding in locating potentially buried pods, such as a system employing a transponder or the like. A life-saving pod capable of installation and transportation within a mine, for providing protection against the aforementioned dangers and other hazards, and remedying the above listed deficiencies is desired. 
       SUMMARY 
       [0005]    The underground Mine Rescue Pod (“pod”) is an emergency safety pod developed for the purpose of sustaining lives of miners in case of disaster. The pod&#39;s exterior rigid steel frame, which may for example be constructed to MSHA canopy standards, is designed to withstand a typical mine-roof fall and to protect miners against possible secondary explosions and noxious atmospheric elements. Use of fire-resistant insulation creates heat-resistant walls for the pod. The pod also has a substantially airtight interior. 
         [0006]    The pod&#39;s interior provides an atmosphere-controlled environment, housing emergency equipment such as an oxygen generator, nourishment, and a transponder for communication between occupants of the pod and persons and/or equipment outside the pod, such as a rescue team. Additionally, the pod is equipped with both interior and exterior air quality sensors for monitoring levels of various gases inside and outside the shelter, and other air quality characteristics. 
         [0007]    In one aspect, the invention provides a pod comprising a substantially airtight structure, including an oxygen supply system, batteries, charging equipment and equipment for monitoring the interior atmosphere of the pod. 
         [0008]    In another aspect, the invention provides a pod comprising a substantially airtight structure, including an oxygen supply system, batteries, charging equipment and equipment for monitoring the atmosphere in the vicinity of the exterior of the pod and relaying the information to the interior of the pod. 
         [0009]    In another aspect, the invention provides a pod comprising a substantially airtight structure, including an oxygen supply system, batteries, charging equipment and equipment for maintaining a positive air pressure within the interior atmosphere of the pod. These and other features and advantages of the invention will be more clearly understood from the following detailed description and drawings of preferred embodiments of the present invention 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a plan view of an underground mine rescue pod according to a preferred embodiment of the invention. 
           [0011]      FIG. 2  is a front view of the pod of  FIG. 1 . 
           [0012]      FIG. 3  is a side view of the pod of  FIG. 1 . 
           [0013]      FIG. 4  is a view of detail A of  FIG. 1 . 
           [0014]      FIG. 5  is a view of detail B of  FIG. 1 . 
           [0015]      FIG. 6  is a cross-sectional elevation view of an underground mine rescue pod according to an alternate embodiment of the invention. 
           [0016]      FIG. 7  is a cross-sectional view of a door of the pod of  FIG. 6 . 
           [0017]      FIG. 8  is a view taken along section line VIII-VIII of  FIG. 9 . 
           [0018]      FIG. 9  is a view taken along section line IX-IX of  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0019]    In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which are shown by way of illustration preferred embodiments of the invention. These embodiments are described in sufficient detail to enable those skilled in the art to make and use them, and it is to be understood that structural, logical or procedural changes may be made. 
         [0020]    Refer now to  FIG. 1 , there being shown an underground mine rescue pod, generally designated by reference numeral  10 , according to a preferred embodiment of the invention. The pod  10  is generally rectangular in shape having walls  20 , including sidewalls  22  and  24 , a front wall  23 , back wall  21 , a top wall  25  ( FIG. 2 ) and a bottom wall  26 . The front wall  23  has an aperture  28  sealable by a door  30 . The pod  10  contains supplies and equipment for life support for miners or other persons in emergency situations. The equipment includes a number of non-gas-emitting type batteries  61  for providing power to the pod  10 . Suitable charging equipment  69  for charging the batteries  61  is also provided. Typically, the pod  10  will be placed at or near a substation  70  for each such unit in the mine, or where power is available. A connection  71  may be provided on the pod  10  for connecting the pod  10  through power and communications equipment  73  into available power and communication lines at the substation  70 . The charging equipment  69  is also connectable with the substation  70 . 
         [0021]    An oxygen supply system  62  may include tanks of oxygen or one or more oxygen generators. Suitable oxygen generators could include, for example, those provided by Chembio Shelter Inc. of Allentown, Pa. Alternatively, an oxygen candle and carbon monoxide (CO) curtain (not shown) may be used in the oxygen supply system  62 . An oxygen candle is a canister that, when activated, emits oxygen as a result of a chemical reaction. A CO curtain absorbs CO and is typically flat and flexible, and may be rolled up for storage. Suitable example of oxygen candles and CO curtains are also provided by Chembio Shelter, Inc. 
         [0022]    Also within the pod  10  are a chemical commode  63 , line communication equipment  67 , which may be telephone equipment, and a location beacon  66 , which may be, for example, a transponder. Moveable components may be placed in an interior overhead shelf  68  that may also hold food and water. In use, the location beacon  66  may emit a signal to aid searchers, rescuers or other miners in locating the pod  10 . 
         [0023]    Along the sides of the pod are bench seats  64 . The oxygen supply system  62  and other equipment may be stored under the seats  64 . The pod  10  may be made corresponding to the dimension of the mine shaft, in a preferred embodiment. In the illustrated embodiment, the pod  10  is about sixteen feet long, about fifty inches high and about seventy-seven inches wide. This size should be able to hold about fourteen people and support them for about ninety-six hours. Alternatively, the pod  10  may be sized to shelter sixteen people for approximately 600 hours. Other sizes could be used. 
         [0024]    An exterior air quality display  65  provides information from an exterior air quality sensor  60  regarding the atmospheric and air quality conditions outside of the pod  10 . An interior air quality sensor and display unit  72  monitors and provides information regarding the atmospheric conditions within the pod  10 . As an additional safety measure, and in particular against any cracks or faults in the integrity of the pod  10 , an air pressure system  83  may be provided, such as a valve  84  responsive to a pressure sensor  85  to release oxygen at a rate to maintain a positive air pressure within the pod  10 . In use, the positive air pressure equipment maintains a slightly higher pressure inside the pod  10  as compared with air pressure outside the pod. As such, the air pressure system  83  minimizes the risk of noxious gases that may exist exterior of the pod from seeping into the interior of the pod  10 , and further endangering the occupants. 
         [0025]    Referring now to  FIG. 2 , the door  30  is shown in greater detail. In the illustrated embodiment, the door  30  has two hinges  40 . Four lever locks  50  are provided, one at each corner of the door  30 . In a preferred embodiment, the bottom wall  26  is lined with mild steel, which may be ⅝ inch mild steel, which functions as a sled when the pod  10  is moved. A pull eye  27  ( FIG. 3 ) is provided at each bottom corner, for example, for moving the pod  10 .  FIG. 3  shows a side view of the pod  10 . The top wall  25 , side walls  22 , front wall  23  and back wall  21  are made of one-inch thick mild steel plate in a preferred embodiment. 
         [0026]    With reference to  FIG. 4 , the wall construction of detail A ( FIG. 1 ) is shown. The walls in a preferred embodiment may include structural H-beams  29  having faces, and plates  54  and  56 . In a preferred embodiment, all of the walls  21 ,  22 ,  23 , and  25  of the pod  10  are of similar construction. The space between the plates  54  and  56  is filled with a fire resistant insulation  58 . The fire resistant insulation  58  may be blown into the space as foam and allowed to harden. In one embodiment, the H-beams  29  are four-inch H-beams that are rated 14 pounds per foot. 
         [0027]    With reference to  FIG. 5 , detail B ( FIG. 1 ) of a portion of the door  30  is described. Hinges  40  include arms  41  that extend to pivot in the eye  42  attached to the front wall  23 , preferably proximate an H-beam  29 . The locks  50  can be rotated to engage the angled catch  51  with the angle iron  52  to lock the door  30  to seal the aperture  28 . A fire resistant door gasket  53  is compressed upon the engagement of the angle iron  52  by catch  51 . The gasket  53  may be similar to gasket materials used in oven doors. In use, the locking arrangement of  FIG. 5  should result in an air-tight attachment of the door  30  to the wall  23  of the pod  10 . 
         [0028]    Refer now to  FIGS. 6 through 9 , there being shown an underground mine rescue pod, generally designated by reference numeral  110 , according to an alternate embodiment of the present invention. The pod  110  has wider spacing along its walls  120  between the H-beams  129 , as compared with the pod  10 . Also, the pod  110  has a circular door that is shown in its locked position in  FIG. 7 . The door  130  has a groove  132  that engages an edge of a ring  131  of the pod  110 . The door  130  also has inner protrusions  133  that provide alignment with the ring  131 . The door  130  may be hinged (not shown). 
         [0029]    While the invention has been described in detail in connection with preferred embodiments known at the time, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention.

Summary:
An rescue pod is disclosed having walls providing a substantially airtight interior, a transponder for communication, interior and exterior atmospheric monitoring systems. The disclosed rescue pod also has support equipment, systems for powering the equipment, and a connection for providing access to external communications and power sources. The rescue pod also comprises a positive air pressure system.