Abstract:
A filling system for an anesthetic evaporator is improved such that an anesthetic-specifically coded adapter neck ( 5 ) of a bottle adapter ( 1 ) can be introduced into the filler neck of a filling device. An outer polygon ( 7 ) is provided on the bottle adapter and an inner polygon designed correspondingly thereto is provided on the filler neck as anesthetic-specific codings.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of priority under 35 U.S.C. § 119 of German Patent Application 10 2004 061 392.3 Dec. 21, 2004 filed, the entire contents of which are incorporated herein by reference. 
   FIELD OF THE INVENTION 
   The present invention pertains to a filling system for an anesthetic evaporator. 
   BACKGROUND OF THE INVENTION 
   A filling system of the type has become known from U.S. Pat. No. 6,585,016 B1. To make it possible to fill liquid anesthetic into an anesthetic evaporator, a bottle adapter is necessary, which establishes the connection between the storage container for liquid anesthetic and the filling device at the anesthetic evaporator. A collet, which has two grooves for receiving an index collar arranged at the neck of the storage container, is provided at the bottle-side end of the bottle adapter. The index collar has an anesthetic-specific design, so that only the bottle adapter fitting the storage container can be screwed on the thread of the bottle. 
   An anesthetic-specific coding in the form of two projections, which are arranged offset at an angle in relation to one another and which engage corresponding openings on the filler neck of the filling device, is likewise provided on the adapter neck of the bottle adapter. 
   The outlet pipe of the bottle adapter is closed by means of a spring-loaded adapter valve, so that no anesthetic vapor can enter the environment. A corresponding filling valve is provided at the filling device. A stationary bar, whose length is selected to be such that the adapter valve can be opened during the introduction of the adapter neck into the filler neck of the filling device, is located in the middle of the filler neck of the filling device. The interaction between the bottle adapter and the filling device is designed such that the filling valve opens first and the adapter valve opens thereafter. Liquid anesthetic can then flow from the storage container into the tank of the anesthetic evaporator. 
   The drawback of the prior-art filling system is that the anesthetic-specific coding on the adapter neck can be introduced into the filler neck of the filling device in a certain preferred position only. 
   SUMMARY OF THE INVENTION 
   The basic object of the present invention is to simplify a filling system of the type in terms of its construction such that the anesthetic-specifically coded adapter neck of the bottle adapter can be introduced into the filler neck in a simple manner. 
   According to the invention, a filling system is provided for an anesthetic evaporator. The filling system comprises a bottle adapter for connection to a storage container for liquid anesthetic. The bottle adapter has an adapter neck. An outer polygon is provided as an anesthetic-specific coding on said adapter neck. A filling device for anesthetic is provided at the anesthetic evaporator with a filler neck for receiving the adapter neck. The filler neck has an inner polygon as an anesthetic-specific coding, which has a design corresponding to that of the outer polygon. 
   The polygon is preferably designed as a regular n-sided polygon. A hexagon, a pentagon or a heptagon may be employed as the polygon. 
   The anesthetic-specific coding designed as a polygon, preferably as a regular n-sided polygon may with different polygons for different anesthetics. For example, a hexagon may be selected as the polygon for the anesthetic halothane, a regular pentagon for enflurane, and a regular heptagon for isoflurane. Thus, no special preferred position is to be complied with for introducing the bottle adapter into the filling device, but the introduction position can be found by slightly rotating the bottle adapter in relation to the filling device. 
   The filling system is such that the bottle adapter is rigidly connected to the storage container. 
   An exemplary embodiment of the present invention is shown in the figures and will be explained in greater detail below. 
   The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings: 
       FIG. 1  is a perspective view of a bottle adapter; 
       FIG. 2  is a longitudinal sectional view of the bottle adapter according to  FIG. 1 ; 
       FIG. 3  is a perspective view of a filling device; and 
       FIG. 4  is a longitudinal sectional view of the filling device according to  FIG. 3 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring to the drawings in particular,  FIG. 1  shows a perspective view of a bottle adapter  1 , which has a collet  2  on its underside for being screwed on a storage container for liquid anesthetic, not shown in  FIG. 1 . On its bottle collar, the storage container has an anesthetic-specific index collar, which is introduced into receiving grooves  3  of the collet  2 . Thus, only a bottle adapter  1  that belongs to the anesthetic can be screwed onto the storage container. The screwing movement is facilitated by recessed grips  4  above the collet  2 . An adapter neck  5  with an O-ring  6  and with an outer polygon  7  for the anesthetic-specific coding as well as an outlet neck  8  with radially extending slots  9  is located at the upper end of the bottle adapter  1 . The top side  10  of the neck is designed as a star  11 . 
     FIG. 2  illustrates the bottle adapter  1  according to  FIG. 1  in a longitudinal section. Identical components are designated by the same reference numbers as in  FIG. 1 . A shut-off valve  12  with a valve piston  13 , a ring  14  on the top side of the valve piston  13  and with a valve spring  15 , which is pretensioned by means of a support plate  16  and presses the valve piston  13  against a sealing surface  131 , is located within the bottle adapter  1 . The support plate  16  is held within the bottle adapter  1  by a support cage  17 . A sealing washer  18 , which lies on the bottle neck of the storage container, not shown in the figures, is fastened on the underside of the support cage  17 . The support plate  16  contains holes  19 , via which the exchange of gas and liquid takes place. The polygon  7  has an anesthetic-specific design, e.g., a hexagon for halothane, a regular pentagon for enflurane, and a regular heptagon for isoflurane. 
     FIG. 3  shows a perspective view of a filling device  20  for anesthetics at an anesthetic evaporator  21 . A filling device  20  has a filler neck  22  with a cylindrical sealing surface  23 , an inner lead-in bevel  24  at the upper end of the filler neck  22 , a spoked wheel  25  with radially inwardly pointing bars  26 , an inner polygon  27  for the anesthetic-specific coding, and a filling valve  28 . 
     FIG. 4  illustrates a longitudinal section of the filling device  20 . Identical components are designated by the same reference numbers as in  FIG. 3 . The filling valve  28  comprises a valve plate  29  at a valve guide bar  30 , which is received in a hole  31  of the evaporator housing  32  in such a way that it can perform lifting movements. The top side  33  of the valve plate  29  is pressed by means of a valve spring  34  against a sealing crater  35  of the filling valve  28 . A guide ring  36  is connected with the valve plate  29  and can be displaced together with the valve plate  29 . 
   The filling system according to the present invention operates as follows: 
   When the bottle adapter  1  is plugged into the filling device  20 , the O-ring  6  first slides over the lead-in bevel  24  and is in contact with the sealing surface  23  of the filler neck  22 . The outer polygon  7  will later engage the inner polygon  27  and the bottle adapter  1  is centered in relation to the filling device  20  as a result. The rods or bars  26  will then be located in the slots  9  of the outlet neck  8  and the outlet neck  8  will enter the area of the guide ring  36 . 
   Due to the bottle adapter  1  being pressed, the neck top side  10  of the bottle adapter is in contact with the top side  37  of the guide ring  36  and the filling valve  28  opens. The adapter valve  12  is still closed. If the pressure on the bottle adapter  1  is increased further, the valve plate  29  is displaced against the force of the valve spring  34  farther downward and the bars  26  touch the ring  14  of the valve body  13 , as a result of which the adapter valve  12  opens. Anesthetic is now flowing from the storage container via the holes  19  of the support plate  16  into the tank of the anesthetic evaporator and, as in communicating vessels, gas flows back into the storage container via the holes  19  from the tank. 
   When the filling operation is terminated, the adapter valve  12  closes at first, so that possible residual quantities of anesthetic within the filler neck  22  can flow off into the tank of the anesthetic evaporator  21 . The filling valve  28  is then closed and the bottle adapter  1  can be removed from the filler neck  22 . 
   While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.