Abstract:
A bottle charged with a gaseous material intended to be discharged through a range of temperatures but not outside that range, has a valve through which the gaseous material is to be directed. The valve has at least a part wholly inside the bottle, which part has a restricted port through it through which the gaseous material passes to issue from the valve, and a thermally responsive member adapted to block the port when the temperature of the interior of the bottle is outside the range. Preferably, the gaseous material is both introduced to the bottle and discharged from the bottle through the same valve, and the valve has a fill port of larger diameter than the restricted port, and an axially moveable actuating element, and the thermally responsive member is carried by the actuating element.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
         [0001]    Not Applicable.  
         BACKGROUND OF THE INVENTION  
         [0002]    The valved bottle of this invention is described as being filled with a mixture of nitrogen as a carrier gas and ethanol, the mixture being used to standardize or calibrate a breath alcohol testing device, but its utility is not confined thereto. In calibrating breath alcohol determining devices, it is essential that a calibrating gas be uniform and of exactly known alcohol content. The temperature of the ambient air around the cylinder is not a certain measure of the condition of the gaseous mixture within the bottle. It is an object of this invention to provide a valve with means for cutting off the discharge of such gaseous material when the temperature inside the bottle is outside a desired range. For example, when the gaseous material is a common nitrogen/ethanol mixture, the valve is disabled at a temperature of about 35° F. (1.7° C.), or in any event, a temperature above the dew point of the mixture. As another example, when the gaseous material is oxygen being administered to a patient, it may be desirable to maintain the temperature of the oxygen within a fairly narrow range, which can be accomplished with a valve of this invention. Another source of possible heterogeneity when the gaseous material is a mixture, is in the filling process. In valves through which a mixture of gas and volatile liquid is both introduced to a bottle or tank and discharged from the bottle or tank, conventionally, the passages through which the gas mixture flows in filling and discharging are the same. When the whole or a part of these passages is restricted, and the pressure drop over the restricted passage during the filling process is great, the expansion of the gas as it leaves the restricted passage can so cool the mixture as to cause the volatile liquid to drop out of the mixture (outgas). In addition, the restriction drastically slows the filling process. Accordingly, it is a further object of this invention to provide a valve that permits faster filling and minimizes the danger of precipitating a volatile liquid component from a gaseous mixture during the filling process.  
         BRIEF SUMMARY OF THE INVENTION  
         [0003]    In accordance with this invention, generally stated, a bottle charged with a gaseous material intended to be discharged through a range of temperatures but not outside that range, is equipped with a valve through which the gaseous material is to be directed. The valve has a part wholly inside the bottle, the part having a restricted port through it through which the gaseous material passes to issue from the valve, and a thermally responsive member adapted to block the port when the temperature of the gaseous material is outside the predetermined range. The valve also has a fill port of greater diameter than the restricted discharge port, which permits faster filling with less danger of precipitating volatile liquids from a volatile liquid/gas mixture. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0004]    In the drawings:  
         [0005]    [0005]FIG. 1 is a diametric sectional view of a bottle and valve of this invention;  
         [0006]    [0006]FIG. 2 is sectional view of the valve of FIG. 1 in gaseous content discharge condition;  
         [0007]    [0007]FIG. 3 is sectional view of the valve of FIG. 1 in gaseous content discharge blocked condition; and  
         [0008]    [0008]FIG. 4 is an exploded view of the valve, showing its constituent elements.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0009]    Referring to the drawings for one illustrative embodiment of bottle and valve of this invention, reference numeral  1  indicates the bottle, which has a neck  2  with internal threads  3  and a shoulder  4 . In this embodiment, the bottle contains a mixture  6  of nitrogen and (0.08% or 0.10%) ethyl alcohol.  
         [0010]    A valve  10  of this invention has a bonnet  12  with external threads  13  complementary to the threads  3  of the neck, and internal threads  14  to receive a fitting from a fill tank or a fitting of a regulator, control valve or the like into which gas is to be discharged from the bottle. A step  15  forms a seat for an O ring  16 , which, seated on the shoulder  4  forms a seal, as shown particularly in FIG. 1. A stepped internally threaded passage  17  in the bonnet receives an externally threaded annular plug  18  with an axial passage, which cages an O ring  19  resting on an upper surface of an internal shoulder  22 . A lower passage  20 , internally threaded, receives an externally threaded cylindrical neck  26  of a valve body  25 . A channel at the lower end of the neck  26  forms a seat  27  for an O ring  28 , which abuts a lower edge of the skirt defining the passage  20 .  
         [0011]    A radially extending fill passage  29  communicates with the exterior of the body  25  at one end and with an axial passage  30  in the body at its other end. An expanded cylindrical chamber  31  extends from the lower end of the passage  30  to an open end of the valve body  25 . The chamber  31  is defined at its upper end in part by a radial surface  32  which serves as a stop, as will be explained hereinafter.  
         [0012]    The actuating element of the valve includes a stem  40  with an axial passage  41  through it, diametrically extending lateral passages  42  that communicate with the exterior of the stem and with the passage  41 , an intermediate part  43  of larger diameter than the stem  40 , with a seat channel  44  between the intermediate part and the stem to house an O ring  45 , and a thermal valve chamber  50 , of larger diameter than the intermediate part. A radial discharge passage  46  communicates with the exterior of the part  43  and with an axial passage  41 , the lower end of which opens into the thermal valve chamber  50 . An annular channel  48  in the intermediate part  43  houses an O ring  49  below the radial discharge passage  46 , forming a seal against the inner wall of the passage  30 . The thermal valve chamber  50  has an outer radial surface  53 , which abuts the inner surface  32  of the chamber  31 , and an inner radial surface  54  bounded by an annular shoulder  55 , a lower surface of which serves as a seat for a bimetal disc  56 , which is caged between the shoulder  55  and a rim  59  of an orifice plate  57 . The orifice plate  57  has a well  61 , within which a ball  65  is moveably seated, an orifice passage  60  communicating at its upper end with the well  61  and at its lower end with the exterior of the orifice plate, and a spring receiving channel  67 . A radially outwardly extending flange  62  around the lower edge of the orifice plate, abutting the skirt of the valve chamber  50 , limits the upward movement of the orifice plate.  
         [0013]    A spring retainer disc  70  has external threads  73  complementary to the threads  33  of the cylindrical chamber  31 , an axial passage  66 , and an annular spring receiving channel  71 . A helical compression spring  69  is caged between the channel  67  of the orifice plate  57  and the channel  71  of the spring retainer disc  70 .  
         [0014]    In filling the bottle, the stem  40  is moved to its lowest position against the bias of the spring  69 , at which point the radial passage  46  is below the fill passage  29 , so that gas introduced to the neck passage  41  flows through the passages  42 , around the intermediate part  43  and out the fill passage  29 . When the bottle is filled, the stem  40  is permitted to be moved to the position shown in FIG. 1 by the bias of the spring, at which position, the O ring  49  and the O ring  45 , which abuts the underside of the internal shoulder  22  of the bonnet well, seal the bottle against escape of gas.  
         [0015]    In discharging the contents of the bottle at a temperature within the desired range, the stem  40  is depressed only half way, so that the fill passage  29  is isolated by the O ring  49 , as shown in FIG. 2, the gaseous mixture  6  passes through the passage  66 , through the orifice  60 , past the ball  65  and disc  56 , through the passages  47  and  46  of the intermediate part and through the passages  42  and  41 , hence out of the bottle. However, when the temperature on the inside of the bottle reaches a point at which the bimetal disc  50  acts, the disc snaps to a position in which the ball  65  is forced against the orifice  60 , stopping the flow of gas as shown in FIG. 3. In the illustrative example, the initial pressure of gas in the bottle is about 1100 lbs. per square inch, but the orifice  60  is on the order of about ten one-thousandths of an inch (0.01″) in diameter, so the sealing force required of the disc is well within the capacity of commercially available bimetal discs. In the embodiment shown, the disc snaps over at about 35° F. Clearly, if one is concerned with a high temperature rather than a low one, a disc with the property of snapping over at a higher temperature can be used. If it is desired to limit the flow at both a low temperature and a high temperature, it is only necessary to provide two discs in series, because the discs have the virtue of returning to “unsnapped” position when the temperature has risen (or fallen, as the case may be) beyond the critical temperature. It is to be noted that the operation of the valve is independent of the pressure of the gas in the bottle.  
         [0016]    Merely by way of illustration and not of limitation, the stem passage  41  can be {fraction (1/16)}″ in diameter, and the lateral passages, 0.031″, the fill passage  29  can be about 0.043″ in diameter, and the passage defined between the intermediate part  43  and the surrounding wall of the valve body, about 0.015″ wide. Because the intermediate part  43  is, in this illustration, about 0.275″ in diameter, the total volume available around the stem is greater than the volume of the fill passage  29 . Although during the filling process, the radial discharge passage  46  is open to the space between the passage between the intermediate part  43  and the valve body, so that gas can flow between the space and the port  60 , little, if any gas will be introduced to the bottle through the port  60 , because of the availability of the fill passage  29 . As has been indicated, the fill tank gas mixture is at about 1,100 pounds per square inch, so that initially the drop in pressure over the fill port is enough to cause expansion of the gas mixture, hence some cooling of the mixture, but a great deal less than would the drop over the discharge port  60 . As is apparent, the provision of the larger fill port speeds the filling process. If, for some reason, it is desired to empty the bottle quickly, the valve stem can be depressed all the way, as in the filling mode, and the gas mixture allowed to escape.  
         [0017]    Numerous variations in the construction of the valve of this invention will occur to those skilled in the art in light of the foregoing disclosure. The dimensions given in the example are, as indicated, merely illustrative. They can be varied over a wide range, depending upon the application of the device, the fill rate desired, and the kind of gas or gas mixture involved. As to other variations, merely by way of example, a bimetal strip can be used in lieu of the disc, the additional time required for the closing being undesirable but not an insuperable obstacle, as long as the valve is fully closed at the critical temperature. The particular configuration of the valve, and its various elements, can be varied, as long as the thermally responsive element is carried by the stem assembly. The thermally responsive element can actuate a sleeve type valve mechanism. The particular construction of the bottle itself forms no part of the invention and can be varied in any desired way, the valve being configured accordingly These variations are merely illustrative.