Patent Publication Number: US-2007102923-A1

Title: Coupling system

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a coupling system for transfer of an anaesthetic fluid from a bottle to a vaporizer.  
      2. Description of the Prior Art  
      A coupling system for transferring anaesthetic fluid from a bottle to a vaporizer is known that has a bottle part having a first valve with a first spring-loaded valve body and a first reactive body, and a vaporizer part having a second valve with a second spring-loaded valve body and a second reactive body. The bottle part and the vaporizer part are adapted to be coupled together, with the first reactive body being arranged so as to act on the second spring-loaded valve body in an opening direction, and the second reactive body being arranged so as to act on the first spring-loaded valve body in an opening direction so as to form a flow-path for the anaesthetic fluid. A seal is arranged between the first valve body and the first reactive body of the bottle part, and a further seal is arranged between the second valve body and the second reactive body of the vaporizer part.  
      During inhalation anaesthesia, a mixture containing anaesthesia is given to a patient via the respiratory passages. The anaesthesia is usually provided in liquid form in a vaporizer, and a certain amount of fluid is vaporized in accordance with the needs for supply to the patient. The vaporizer contains a limited amount of liquid, and refilling of the liquid may be necessary during a progressive narcosis.  
      When filling liquid to the vaporizer it is important to make sure that the anaesthesia does not reach the surroundings and is vaporized. Above all, there are two reasons for this. A short-term effect is that the nursing staff is negatively affected during surgery by anaesthetic gas. A long-term effect is that staff exposed during extended periods of time to anaesthetic gases can develop cancer.  
      A common disadvantage of known coupling systems is that liquid remains in the coupling when the parts are pulled apart after being coupled together, thereby allowing the liquid to evaporate into the surroundings.  
      In conjunction with a coupling system of the type initially mentioned, and which is described in EP 1 304 132 A1, attempts have been made to solve said problem by arranging the two parts of the coupling system so that the spring-loaded valve body and the reactive body in the respective part substantially form a plane surface. Due to the plane surfaces of the parts, there is in principle no volume between the parts that could be filled with liquid. However, liquid seeping in between the surfaces and forming a liquid film cannot be completely avoided. Since the plane surfaces of the coupling system are relatively large, a considerate amount of fluid can vaporize into the surroundings when the parts are pulled apart.  
     SUMMARY OF THE INVENTION  
      An object of the invention is to present a coupling system of the type initially described that insures that no or a negligible spill of liquid will occur when the bottle is removed from the vaporizer.  
      This problem is solved in a coupling system of the type initially described wherein that the seals are positioned and the reactive bodies are arranged so that, when the bottle part and the vaporizer part are coupled together, the seal of the bottle part abuts sealingly against the second reactive body, and the seal of the vaporizer part abuts sealingly against the first reactive body. The positioning of the seals makes it impossible for fluid to leak during filling and form a film between the parts. After separation of the parts, only a negligible part of the coupling, which during filling was in contact with the fluid, will now come in contact with the surrounding air.  
      In an embodiment of the coupling system according to the invention, the distance between the respective seal and reactive body is such that, upon coupling together of the bottle part and the vaporizer part, the seal of the vaporizer part firstly comes into contact with the first reactive body. Thereby, a tight connection is secured between the vaporizer part and the bottle part before the valve body of the bottle part and the reactive body of the vaporizer part are displaced to a position in which the flow-path for the anaesthetic fluid is open.  
      In preferred embodiment of the coupling system according to the invention the first valve body has a recess. A recess makes it more difficult to open the valve body of the bottle part by mistake.  
      According to a further preferred embodiment of the coupling system according to the invention it is suggested that the second reactive body has a protruding part, the shape of which corresponds to the recess. Thereby, it is difficult to open the spring-loaded valve body of the vaporizer part by mistake. 
    
    
     DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a side sectional view of a coupling system in accordance with the present invention, with a bottle part and a vaporizer part separated from and facing each other.  
       FIG. 2  shows the coupling system of  FIG. 1  in a partially coupled, but still closed, position.  
       FIG. 3  shows the coupling system according to  FIGS. 1 and 2 , in a position wherein the inlet of the vaporizer part is partly opened but the outlet of the bottled part is closed.  
       FIG. 4  shows the coupling system of  FIGS. 1, 2  and  3  in an open position allowing gas flow therethrough.  
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      In  FIG. 1 , a coupling system is shown in a side view with a bottle part  1  and a vaporizer part  2  shown in longitudinal cross-section, which parts are shown facing each other. The bottle part  1  is fitted to or is a part of a bottle  3 , and the vaporizer part is mounted in a vaporizer  4  of a narcosis apparatus.  
      The bottle part  1  has a first valve formed by a spring-loaded valve body  5  and a reactive body  6 . The reactive body  6  is formed by the free end side of the bottle part  1 . Between the valve body  5  and the reactive body  6  a seal  7  is provided in the form of an O-ring seal that is fastened to the valve body  5 . The spring  8  for the valve body  5 , pushing the seal  7  against the inner side of the reactive body  6 , is, as shown in the Figure, tightened between a lock ring  9  and the side of the valve body  5  that is directed towards the lock ring  9 . The valve body  5  is also provided with channels  15 .  
      The vaporizer part  2  has a second valve with a spring-loaded valve body  10  and a reactive body  11 , which bodies  10 ,  11  are placed in a housing  14 . Between the valve body  10  and the reactive body  11  a seal  12  is provided in the form of a O-ring seal, which is fastened to the valve body  10 . The spring  13  for the valve body  10 , which pushes the seal  12  against the lower side of the reactive body  11 , is tightened between the inner side of the housing  14  of the vaporizer part  2  and the side of the valve body  10  that is facing said inner side. The reactive body  11  forms a part of a shaft  16 , which is fixed to the bottom  17  of the housing  14 . The bottom  17  is provided with channels  18 .  
       FIG. 2  shows that, upon coupling together of the parts  1  and  2 , i.e. when the bottle part  1  is brought into the vaporizer part  2 , the seal  12  of the vaporizer part  2  will at first come into contact with the reactive body  6  of the bottle part  1  and form a seal between the bottle part  1  and the vaporizer part  2  before any of the valves  5 ,  6 , and  10 ,  11 , respectively, of the parts have been opened.  
       FIG. 3  shows that, upon a further displacement of the bottle part  1  downwardly in the vaporizer part  2 , the reactive body  6  of the bottle part  1  is pressed towards the seal  12  so that the valve body  10  of the vaporizer part  2  is pressed downwards, whereby the seal  12  leaves the lower side of the reactive body  11  of the vaporizer part  2 , causing the inlet to the vaporizer part  2  and thus to the vaporizer  4  to be opened. The seal  7  of the bottle part  1  still abuts against the inner side of the reactive body  6  of the bottle part  1 .  
      When the bottle part  1  is further pushed downwardly towards the vaporizer part  2 , the reactive body  6  of the bottle part  1  pushes the seal  12  and thereby the valve body  10  of the vaporizer part  2  downwards, whereby the inlet to the vaporizer part  2  and thereby to the vaporizer  4  is completely opened. At the same time the valve body  5  of the bottle part  1  is pushed upwards by means of the reactive body  11  of the vaporizer part  2  so that the seal  7  lifts from the inner side of the reactive body  6  of the bottle part  1 , whereby a flow-path for the anaesthetic fluid through the coupling system is formed, which is shown in  FIG. 4 . Now fluid can flow from the bottle  3  through the channels  15  in the valve body  5  and through the opening formed around the valve body  5  of the bottle part  1  and the reactive body  11  of the vaporizer part  2 , which opening is indicated by arrows  19 , and further into the vaporizer  4  ( FIG. 1 ) through the channels  18 .  
       FIG. 4  shows the parts of the coupling system that, upon filling of anaesthetic fluid, will come into contact with the fluid and that, after a separation of the bottle part and the vaporizer part, will come into contact with the surroundings. These parts are the surface of the peripheral part  20  of the reactive body  11  of the vaporizer part  2 , and the surface of the inner ring of the reactive body  6  of the bottle part, which in  FIG. 4  is indicated by the reference numeral  21 . The peripheral part  20  and the inner ring  21  are also indicated in  FIG. 1 . The fluid that possibly can stick to these small surfaces is negligible.  
      When the bottle part  1 , after completed filling of anaesthetic fluid to the vaporizer  4 , is pulled upwards out of the vaporizer part, a closing of the valves  5 ,  6  and  10 ,  11  with their seals  7 ,  12  takes place so that the bottle part  1  as well as the vaporizer part  2  are sealed before the bottle part  1  and the vaporizer part  2  have been pulled apart. The closing of the parts  1  and  2  takes place in an inverted order as compared to what has been described above in connection with  FIGS. 1-4 .  
      In  FIGS. 1-4 , it is shown that the valve body  5  of the bottle part  1 , as described above, can have a recess  22 . Also the reactive body  11  of the vaporizer part  2  can have a protruding part  23 , the shape of which corresponds to fit into recess  22 . The advantages of this are presented above in the introduction of the description. The coupling system according to the invention works in the same way as described, even if the valve body  5  and the reactive body  11  are replaced by a planar arrangement.  
      Although modifications and changes may be suggested by those skilled in the art, it is the invention of the inventor to embody within the patent warranted heron all changes and modifications as reasonably and properly come within the scope of the inventor&#39;s contribution to the art.