Abstract:
A portable liquid oxygen (LOX) storage/delivery apparatus is provided, including an insulated (LOX) container having an interior, a top portion, a bottom portion and a sidewall, the sidewall including a first side portion and a second side portion, both extending between the top portion of the bottom portion, and a port system in communication with the interior of the container for charging the container and for withdrawing LOX and gaseous oxygen from the container.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   The present application is a divisional of U.S. application Ser. No. 09/696,208, filed Oct. 26, 2000 now U.S. Pat. No. 6,575,159, which claims priority from U.S. Provisional patent application Ser. No. 60/162,133, filed Oct. 29, 1999. The disclosure of the above-referenced provisional patent application is incorporated herein by reference in its entirety. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to a portable liquid oxygen unit. 
   2. Description of the Background Art 
   Therapeutic oxygen is the delivery of substantially pure oxygen to a patient in order to facilitate breathing. When a patient suffers from pulmonary/respiratory problems, delivery of oxygen helps the patient get an adequate level of oxygen into his or her bloodstream. 
   Therapeutic oxygen may be warranted in cases where a patient suffers from a loss of lung capacity. Medical conditions that may make oxygen necessary are chronic obstructive pulmonary disease (COPD), including asthma, emphysema, etc., as well as cystic fibrosis, lung cancer, lung injuries, and cardiovascular diseases, for example. 
   Related art practice has been to provide portable oxygen in two ways. In a first approach, compressed oxygen gas is provided in a pressure bottle, and the gas is output through a pressure regulator and a hose to the nostrils of the patient. The bottle is often wheeled so that the patient may be mobile. The drawback of compressed, gaseous oxygen is that a full charge of a bottle that is portable does not last very long. 
   In order to get around this limitation, in a second approach a related art liquid oxygen (LOX) apparatus has been used wherein LOX is stored in a container and the gaseous oxygen that evaporates from the LOX is inhaled by the patient. 
   The related art LOX apparatus enjoys a longer usable charge than the compressed gas apparatus for a given size and weight, but has its own drawbacks. LOX, being a liquid that is very cold, requires a vacuum-insulated container. 
   Related art portable LOX units typically are formed with necks that can fill with LOX when tipped, and thus are to be used and carried only in a generally vertical position. This can be impractical at times, such as when driving a vehicle, for example. A vertically positioned related art portable LOX unit is unstable and could potentially cause problems for both the oxygen user and for other drivers if it shifts, slides, or tumbles. 
   There remains a need in the art, therefore, for an improved portable LOX unit. 
   SUMMARY OF THE INVENTION 
   A portable liquid oxygen (LOX) storage/delivery apparatus is provided according to the invention. The portable liquid oxygen (LOX) storage/delivery apparatus comprises an insulated (LOX) container having an interior for containing LOX, the LOX container having a top portion, a bottom portion and a sidewall between the top and bottom portions, the sidewall including a first side portion extending between the top portion and the bottom portion of the container, and a second side portion extending between the top portion and the bottom portion of the container, the second side portion being on an opposite side of the container from the first side portion, a port system in communication with the interior of the container for charging the container with LOX, and for withdrawing LOX and gaseous oxygen from the container, wherein the gaseous oxygen is withdrawn from the container through a first outlet communicating with the interior of the container, the first outlet being located adjacent a first juncture between the top portion and the first side portion of the container; wherein LOX is withdrawn from the container through a second outlet communicating with the interior of the container, the second outlet being located adjacent a second juncture between the bottom portion and the second side portion, and wherein gaseous oxygen can be withdrawn from the container through the first outlet and LOX can be withdrawn from the container through the second outlet when the container is positioned in a first orientation with the sidewall vertically oriented, as well as when the container is positioned in a second orientation with the second side portion oriented downwardly and with the first side portion oriented upwardly and overlying the second side portion, and in all positions in between. 
   The above and other features and advantages of the present invention will be further understood from the following description of the preferred embodiment thereof, taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  schematically shows one embodiment of a portable liquid oxygen unit of the present invention in a first position; 
       FIG. 2  schematically shows an alternate position of the portable LOX unit illustrating how the portable LOX unit of the present invention may be used in different orientations; 
       FIG. 3  schematically shows a detail of an insulated support system of the present invention; and 
       FIG. 4  schematically shows the portable LOX unit of the present invention being used in a portable LOX system. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1  shows one embodiment of a portable liquid oxygen unit  100  of the present invention. The portable LOX unit includes an outer shell  101  and a container  104  within the outer shell  101 . 
   A space  110  exists around the container  104  and is preferably evacuated to at least a partial vacuum. In the illustrated embodiment, the container  104  is held and supported within the outer shell  101  by an optional top support  118  and an optional bottom support  119  (discussed below in conjunction with  FIG. 3 ). The container  104  may be insulated or may be formed of a material having heat insulating properties. 
   The container  104  is formed of a top portion  105 , a bottom portion  106 , and a sidewall  107 . The sidewall  107  includes a first side portion  108  and a second side portion  109 , both extending between the top portion  105  and the bottom portion  106 , but with the second side portion  109  being on an opposite side of the container  104  from the first side portion  108 . 
   The container  104  also includes a liquid withdrawal conduit  113  and a gaseous withdrawal conduit  116 . The gaseous withdrawal conduit  116  allows withdrawal of gaseous oxygen from the container  104 . The gaseous withdrawal conduit  116  enters the container  104  and has a first outlet  117  communicating with an interior of the container  104 . The first outlet  117  is located adjacent a first juncture between the top portion  105  and the first side portion  108  of the container  104 . 
   The gaseous withdrawal conduit  116  exits both the container  104  and the outer shell  101 , and forms a first port  440  in the container  104  and in the outer shell  101  (see  FIG. 4 ). The first port  440  is located adjacent the first juncture between the top portion  105  and the first side portion  108  of the container  104 . 
   The liquid withdrawal conduit  113  allows withdrawal of LOX from the container  104 . The liquid withdrawal conduit  113  extends diagonally across the interior of the container  104  and has a liquid withdrawal (second) outlet  114  positioned in the bottom portion  106  of the container  104 . The second outlet  114  is located adjacent a second juncture between the bottom portion  106  and the second side portion  109 . The liquid withdrawal conduit  113  may exit through a second port  441  adjacent the first port  440 , with the second port  441  preferably being concentric with the gaseous withdrawal conduit  116  and exiting within the first port  440 . Thus, at least a portion of the liquid withdrawal conduit  113  may be located within the gaseous withdrawal conduit  116 . 
     FIG. 2  shows an alternate position of the portable LOX unit  100  illustrating how the portable LOX unit  100  may be used in different orientations. As can be seen from the figure, the second outlet  114  of the liquid withdrawal conduit  113  still resides at a low point of the container  104 . It can also be seen from the figure that the first outlet  117  of the gaseous withdrawal conduit  116  remains at a high point in the portable LOX unit  100 . Even in a horizontal orientation, the portable LOX unit  100  maintains the liquid withdrawal conduit  113  and the gaseous withdrawal conduit  116  at desired positions to enable both LOX and gaseous oxygen withdrawal. Therefore, the position of the portable LOX unit  100  is not limited by the internal configuration of withdrawal conduits. 
     FIG. 3  shows a detail of the insulated support system  119 . The insulated support system  119  supports and positions the container  104  within the outer shell  101  (see  FIGS. 1 and 2 ). A top insulated support  118  is centrally located on the top portion  105  of the container  104  and extends upwardly from the top portion  105 . A bottom insulated support  119  is centrally located on the bottom portion  106  of the container  104  and extends downwardly from the bottom portion  106 . 
   The insulated support system  119  includes an outer shell support  121 , a container support  124 , and an insulated support  127 . The outer shell support  121  is attached to the outer shell  101  (top or bottom), while the container support  124  is attached to the container  104 . The insulated support  127  is attached to neither and is merely placed between the two for the purposes of cushioning and insulating. Therefore, the container supports  124  of both the top and bottom insulated support systems  118  and  119  are telescopically received by the respective outer shell supports  121 . 
   It should be noted that the insulated support  127  is preferably made of an insulating material. This is done to minimize heat transfer from the outer shell  101  to the container  104 . Due to the insulated support  127 , the container support  124  does not come into contact with the outer shell support  121 . 
     FIG. 4  shows the portable LOX unit  100  of the present invention being used in a portable LOX system  400 . The portable LOX unit  100  further includes a third port  401  and a LOX delivery conduit  402 . The LOX delivery conduit  402  enters the outer shell  101  through a third port  401  and also enters the container  104 . The third port  401  is located adjacent a third juncture between the first side portion  108  and the bottom portion  106  (see  FIG. 1 ). The LOX delivery conduit  402  terminates with an open end  404  located within the container  104  and adjacent the top portion  105  of the container  104 . Preferably, the open end  404  is centrally located within the top portion  105 , so that when LOX is being charged into the container, it flows along the internal sidewall portions of the container so as to minimize turbulence of LOX within the container, thereby facilitating maximal filling of the container with LOX. 
   Also shown in  FIG. 4  is the emergence of the gaseous withdrawal conduit  116  and the liquid withdrawal conduit  113  from the portable LOX unit  100 . In this embodiment, both conduits  113  and  116  concentrically emerge from the container  104 , and then emerge from the outer shell  101  at the first port  440 . 
   While the invention has been described in detail above and shown in the drawings, the invention is not intended to be limited to the specific embodiments as described and shown.