TECHNICAL FIELD 
       [0001]    The present invention relates to a connector able to be mounted on the open end of the neck of a bottle, the connector having a main longitudinal axis X-X and comprising: 
         [0002]    a main body, which comprises constraining means for constraining the connector to the container and a sleeve able to connect the inside of tie container to the external environment; 
         [0003]    a slider which is slidably inserted in the sleeve and is able to move longitudinally between a closed bottom position, where the slider does not allow liquid to out from the container, and an open upper position, where the slider allows liquid to flow out from the container; the slider defining internally a seat able to receive a probe able to allow dispensing of the liquid; 
         [0004]    the slider further comprising: 
         [0005]    a central portion able to be guided at least partially by the sleeve; 
         [0006]    a bottom portion, protruding from the sleeve towards the outside of the container when the slider is in the bottom closed position, and comprising a plurality of longitudinally elongated parts, which, when the slider is in the bottom closed position, reversibly engage with a corresponding engaging portion formed in the probe by expanding elastically in a radial direction with respect to the longitudinal axis X-X. 
       BACKGROUND OF THE INVENTION 
       [0007]    This type of connector may be used on containers with a neck, such as bottles, in combination with devices for controlled dispensing of the beverages present inside the containers. 
         [0008]    The devices for controlled dispensing of beverages referred to are already known in the art and comprise, in brief, control means, a probe able to be inserted inside the connector, an end unit by means of which it is possible to dispense the beverage and, in some cases, also a source of carbon dioxide or other inert gas. 
         [0009]    When probe is inserted inside the connector, which is positioned on the mouth of the container and the latter is arranged with its mouth directed downwards, the device is ready for dispensing. 
         [0010]    If the container is one of the ones which contain water, such as for example the ones which can be found in the offices, the dispensing device will comprise refrigerating means; if the container is a bottle containing an alcoholic beverage and the dispensing device is suitable for preparing a cocktail, it will comprise a source of inert gas which is able to exert on the beverage a pressure which allows it to easily reach the end unit from which it must be dispensed. 
         [0011]    These latter devices are becoming increasingly popular in bars since, with them, precise quantities of beverages also of a varying nature may be rapidly dispensed; in this way, the cocktails which are normally served in these premises may be prepared much more precisely and quickly. 
         [0012]    The connectors used on the bottles designed for this type of dispensing device comprise a main body which, during use, is constrained to the container and a slider positioned inside the main body. These connectors are very similar to the one described in the American patent U.S. Pat. No. 4,375,864 which discloses a connector suitable for use in water dispensers, 
         [0013]    The main disadvantage of the connectors known hitherto is that they are able to ensure sealing of the container only before initial opening and, thereafter, only when probe is inserted inside them. 
         [0014]    In bars, however, there is a need to have a connector which is able to ensure sealing of the container also after initial opening and without probe necessarily having to be inserted. 
         [0015]    This technical effect would allow temporary interruption during dispensing of the beverage present in the container, while ensuring, at the same time, that there is no risk of accidentally introducing into the container substances which are foreign to the liquid present therein and that there is no accidental leakage of liquid. 
         [0016]    In WO00/07902 there is disclosed a connector in which the jacket where the slider is located needs to comprise a narrowed portion for elastically biasing the probe radially inwards in order for the slider to engage the probe. 
         [0017]    The movement of the probe towards the interior of the container must therefore be limited so that the slider does not fall within the container but remains at least partly within the narrowed portion of the jacket. 
         [0018]    This poses a further limit to the overall cross section of the openings which allow the fluid to flow outside of the container. 
         [0019]    On top of this, the disclosed connector requires at least two separate sealing surfaces, i.e. where the two O-rings are represented, requiring a rather complex manufacturing. 
         [0020]    U.S. Pat. No. 5,289,855 to Baker et al. discloses a connector where the engagement between the probe and the slider is obtained by virtue of elastic deformation of the thickness of the material of the slider walls. Such an engagement requires strict tolerances and a precise dimensioning of the elements. 
         [0021]    It would therefore be desirable to provide a connector which does not suffer from the limitations of the prior art, having openings for the passage of the fluid whose cross-section is not limited with respect to the size of the neck of the container and which, at the same time, is simpler to manufacture. 
         [0022]    In view of the state of the art described, the object of the present invention is to provide connectors able to satisfy the requirements described above more so than known hitherto. 
         [0023]    As a result of he present invention it is possible to provide a connector able to allow a large number of opening and closing cycles following insertion/extraction of probe of the dispensing device, which allows higher pouring rates than the ones achievable by prior art connectors and which does not require a complex manufacturing method for being made. 
         [0024]    Moreover, a further advantage of the present connector is that it is possible to use it in bars, in particular in combination with containers containing alcoholic beverages, allowing them to disconnect the probe from the connector without the alcohol contained in the beverages being able to evaporate, altering the organoleptic properties thereof. 
       SUMMARY OF THE INVENTION 
       [0025]    In accordance with the present invention, this object is achieved by means of a connector able to be mounted on the open end of the neck of a bottle, the connector having a main longitudinal axis X-X and comprising: 
         [0026]    a main body, which comprises constraining means for constraining the connector to the container and a sleeve able to connect the inside of the container to the external environment; 
         [0027]    a slider which is slidably inserted in the sleeve and is able to move longitudinally between a closed bottom position, where the slider does not allow liquid to flow out from the container, and an open upper position, where the slider allows liquid to flow, out from the container; the slider defining internally a seat able to receive a probe able to allow dispensing of the liquid; 
         [0028]    the slider further comprising: 
         [0029]    a central port-ion able to be guided at least partially by the sleeve; 
         [0030]    a bottom portion, protruding from the sleeve towards the outside of the container when the slider is in the bottom closed position, and comprising a plurality of longitudinally elongated parts, which, when the slider is in the bottom closed position, reversibly engage with a corresponding engaging portion formed in the probe by expanding elastically in a radial direction with respect to the longitudinal axis X-X. 
         [0031]    wherein the connector further comprises an upper portion having a conical shape terminating in an end having the outer diameter d 4  such as to engage, with slight interference, with the upper portion of the main body; 
         [0032]    the main body having, in the vicinity of its upper end, a circumferential projection projecting towards the inside of main body and with an inner diameter d 5 , the connector being such that when the upper portion of the slider passes over the projection, the bottom pork-ion of the slider is situated inside the sleeve 
         [0033]    Preferably, the longitudinally elongated parts each comprise a tooth, 
         [0034]    According to a possible embodiment, the main body comprises: 
         [0035]    a sleeve with an inner diameter d; 
         [0036]    an upper portion having an inner diameter d 3 &gt;d 1 ; 
         [0037]    the sleeve being longitudinally closer to the mouth of the container than the upper portion, when the connector is fixed to the container; 
         [0038]    the upper portion comprising a circumferential projection projecting towards the inside of the main body and having a height h such that h&lt;d 5 −d 3 /2. 
         [0039]    The slider mazy also comprise a central portion with an outer diameter d 2  and an upper portion having an outer diameter d 4 &gt;d 2 , wherein the central portion is longitudinally closer to the mouth of the container than the upper portion, when the connector is fixed to the container and the slider is in the bottom closed position. 
         [0040]    Preferably, the inner diameter d 1  of the sleeve provides a liquid-tight seal when the sleeve is engaged with the outer surface of the slider or with the central portion of the slider or with the outer surface of the channel of the probe. 
         [0041]    In an advantageous embodiment, d 1  is substantially equal to d 3 , and d 2  is substantially equal to d 4 . 
         [0042]    The slider may comprise a generally flat base between its central and bottom portions. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0043]    The characteristic features and advantages of the present invention will become clear from the following detailed description of a practical embodiment provided by way or a non-limiting example, with reference to the accompanying drawings, in which: 
           [0044]      FIG. 1  shows a partial cross-section and a partial front view of an example of a connector according to a preferred embodiment of the present invention, mounted on the mouth of a bottle-like container and a probe able to engage with the connector; 
           [0045]      FIG. 2  shows a partial cross-section and a partial front view of the connector according to  FIG. 1  in the closed configuration with probe completely engaged inside it; 
           [0046]      FIG. 3   a  shows a partial cross-section and a partial front view of the connector according to  FIG. 1  in an intermediate configuration between the closed configuration and the open configuration shown in  FIG. 5 ; 
           [0047]      FIG. 3   b  shows the cross-section of a detail of the connector according to  FIG. 3   a:    
           [0048]      FIG. 4  shows a partial cross-section and a partial front view of the connector according to  FIG. 3   a  in an intermediate configuration between the configuration shown in  FIG. 3   a  and the open configuration; 
           [0049]      FIG. 5  shows a partial cross-section and a partial front view of the container according to  FIG. 1  in the open configuration 
           [0050]      FIG. 6  shows an enlarged view of a detail according to  FIG. 1   
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0051]    With reference to the figures,  100  denotes a container with a longitudinal axis Z-Z, having a neck  101  and a mouth, such as a bottle for example. A probe  103 , which in  FIG. 1  is shown separate from the container/connector assembly, is connected to the apparatus which controls it and which forms the dispensing device. As can be seen in the figures, it has a retaining groove  104  and windows  105  for allowing the introduction of liquid from the container  100  into the channel  106  of probe  103 . 
         [0052]      1  denotes overall a connector which is integrally joined to the container  100  and composed of a main body  3  and a slider  4  situated inside it and longitudinally sliding therein. 
         [0053]    The connector  1  has a longitudinal axis X-X which, when the connector  1  is mounted on container  100 , coincides with the longitudinal axis Z-Z of the container  100 . 
         [0054]    The main body  3  is provided with retaining means able to constrain it firmly to the container  100 . For example, it may advantageously comprise an outer skirt  5  with a lip  7  such as to engage with a suitable locating element formed on the neck  101  of the container  100 , preventing extraction of the connector  1  from the neck  101  of the container  100 . 
         [0055]    The retaining means may also be formed by an inner thread able to engage with a corresponding thread formed on the container  100 . 
         [0056]    The main body  3  may also comprise means able to prevent rotation relative to the container  100 ; these means may advantageously consist of projections which are parallel to the axis X-X and engage with corresponding projections formed on the outer surface of the neck of the container  100 . 
         [0057]    Slider  4  is able to slide longitudinally between a bottom closed position, shown in  FIGS. 1 ,  2  and  6 , where it defines a closed configuration of the connector  1 , and at least one upper open position, shown in  FIG. 5 , where it defines an open configuration of the connector  1 , and vice versa. 
         [0058]    In the bottom closed position, slider  4  ensures the liquid-tightness of the connector  1  and is able to engage with and disengage from probe  103 . 
         [0059]    When connector  1  is in the upper open configuration, slider  4  is completely disengaged from main body  3  and is situated completely within container  100 ; the apertures of windows  105  associated with probe  103  are completely free. 
         [0060]    It is also possible to regard as open those intermediate configurations between the upper open configuration and the bottom closed configuration, which nevertheless allow the liquid to flow out of the container  100 . During the course of the present description reference will be made mainly to the upper open configuration shown in  FIG. 5 . 
         [0061]    The direction from the bottom closed position towards the tipper open position thus defines the bottom-to-top direction and relates to the arrangement of the container  100  when it is being used, i.e. is upside down. 
         [0062]    The connector  1  may furthermore comprise special means (not shown) for indicating attempts to remove the connector  1  from the container  100  or the fact that initial opening has occurred. 
         [0063]    The main body  3  comprises a sliding sleeve  9  which preferably has a circular cross-section and which has a first end  11  such that, when the connector  1  is fixed to the container  100 , the first end  11  is directed towards the mouth of the container  100 ; the first end  11  is therefore the bottom end of the sleeve  9 , according to the definition given above. 
         [0064]    Slider  4  comprises a central guiding portion  6  which is able to be guided by the sleeve  9  of the main body  3  and a bottom, engaging portion  8  which is able to engage reversibly with probe  103  and is arranged towards the mouth of the container  100 , i.e. on the bottom side of the central portion  6 . 
         [0065]    Slider  4  defines inside it a seat  10  able to receive probe  103 . 
         [0066]    When the connector  1  is in the closed configuration, the bottom engaging portion  8  of slider  4  is situated outside the sleeve  9  of the main body  3 . 
         [0067]    In other words, if α indicates the plane perpendicular to the axis X-X and passing through the first end  11  of the sleeve  9  directed towards probe  103 , the bottom portion  8  of slider  4  is situated on the side of the plane a which is opposite to the the sleeve  9 . The bottom portion  8  is able to receive probe  103  by expanding radially. It may be advantageously divided into a plurality, for example six, eight or ten elongated parts  12  which may advantageously be identical to each other and preferably equally spaced along the outer perimeter of the bottom portion  8  of slider  4 . 
         [0068]    Engagement with the retaining groove  104  of probe  103  is achieved by means of teeth  14  which are advantageously formed on the bottom portion  8  and preferably project towards the seat  10 . Advantageously, a tooth  14  is formed on each elongated part  12 . 
         [0069]    In this way, when probe  103  moves longitudinally towards the seat  10  of slider  4 , the conical end  108  of probe  103  will push the bottom portion  8  of slider  4  outwards, boy means of the teeth  14  and the elongated parts  12 , making use of their radial elasticity. 
         [0070]    As soon as teeth  14  have completely passed over the conical part  108  of probe  103 , the elasticity of the elongated parts  12  will allow the teeth  14  to return elastically into their rest position, thus resulting in snap-engagement of the bottom portion  8  Inside the retaining groove  104 . 
         [0071]    The size of the seat  10  of slider  4  is determined so that the base  16  of the seat  10  is in contact with the top end,  109  of probe  103 , which is generally flat so as to allow also the transmission to slider  4  of high longitudinal forces directed towards the centre of the container  100 . 
         [0072]    Advantageously, the distance between the teeth  14  and the base  16  is slightly less than the distance between the top, end  109  and the groove  104 , so as to ensure constant contact between probe  103  and slider  4 . 
         [0073]    The main body  3  comprises, at the end of the sleeve  9  opposite to the bottom end  11 , a first abutment surface  17  able to cooperate with a second corresponding abutment surface  18  formed on slider  4  in the vicinity of the end of the central portion  6  which is longitudinally opposite to the bottom portion  8  and which has an outer diameter d 2 . 
         [0074]    These first and second abutment surfaces  17 ,  18  are preferably formed as surfaces converging towards the plane α, for example frustoconical surfaces and/or surfaces with a cross-section in the form of a circumferential arc, and are respectively adjacent to the inner surface of the sleeve  9  and to the outer surface of the central portion  6  of slider  4 . 
         [0075]    The function of these surfaces is to allow extraction of probe  103  from the seat  10  formed in slider  4  and preventing extraction of slider  4  from the main body  3 , exerting a longitudinal, force greater than the maximum force which the bottom portion  8  is able to exert on probe  103  via the teeth  14 . 
         [0076]    When probe  103  must be extracted from the container  100  and slider  4  reaches the bottom closed position, the two abutment surfaces  17 ,  18  come into abutment with each other and the bottom portion  8  of slider  4  is situated outside the sleeve  9 . 
         [0077]    The bottom portion  8  is formed so that the longitudinal force which It is able to exert via the retaining means (i.e. teeth  14 ) is less than the maximum longitudinal force which the abutment surfaces  17  and  18  may exert. 
         [0078]    Consequently, each additional longitudinal movement of probe  103  out from the seat  10  of slider  4  results n radial expansion of the bottom portion  8 , therefore allowing probe  103  to pass over the teeth  14 . Probe  103  at this point is free from its engagement inside the seat  10 . 
         [0079]    Advantageously, the in diameter d 1  of the sleeve  9  is such that in is able to provide a liquid-tight seal when the sleeve is engaged with the outer surface of slider  4  or with its central portion  6  or with the outer surface of the channel  106 . 
         [0080]    Normally the diameter of channel  106  constitutes one of the design data and consequently determines the dimensions of the other parts. 
         [0081]    On the side of the first abutment surface  17  opposite to sleeve  9  (and therefore above it), the main body  3  comprises an upper portion  19  able to engage with a corresponding upper portion  20  of slider  4 , formed on the opposite side, relative to the first abutment surface  18 , to that of the central portion  6 . 
         [0082]    This upper portion  19  of the main body  3  is advantageously cylindrical, having an inner diameter d 3 &gt;d 1 . 
         [0083]    The bottom portion  19  of the main body  3  has, in the vicinity of its upper end (namely opposite to plane α), a third and a fifth abutment surface denoted by  25  and  27  in  FIG. 2 , respectively. These surfaces are advantageously formed on a circumferential projection  23  projecting towards the inside of main body  3  and with an inner diameter d 5 . 
         [0084]    The abutment surfaces  25  and  27  therefore define two conical surfaces having opposite vertices with respect to the projection  23  and are advantageously inclined relative to axis X-X by about 15° and about 45°, respectively. 
         [0085]    The upper portion  20  of slider  4  terminates in an end  22  opposite to the bottom portion  8  where the outer diameter d 4  is such as to engage, with slight interference, with the upper portion  19  having a diameter d 3 , so as to prevent any relative movements of slider  4  and main body  3 . 
         [0086]    The upper portion  20  may advantageously have a cylindrical section with an outer diameter d 6  (not indicated in the figures), where d 2 &lt;d 6 &lt;d 4  and d 6 &gt;d 5 , joined on one side to the first abutment surface  18  and, on the opposite side, to an additional conical surface which converges towards the bottom portion  8  and the outer diameter of which reaches the value of d 4  substantially at the end  22 . 
         [0087]    In the vicinity of this maximum diameter d 4 , namely above and below it, it is possible to identify a fourth abutment surface  26 , facing the bottom of the container, and a sixth abutment surface  23  which is directed towards sleeve  9  and the functions of which will be described more fully below. 
         [0088]    The surfaces  25  and  27  co-operate with surfaces  28  and  26 , respectively, so as to allow safe opening and closing of the connector  1 . 
         [0089]    In fact, when the upper portion  20 , during its longitudinal movement, passes over projection  23 , the pairs  25 / 28  and  27 / 26  of abutment surfaces produce a peak in the axial resistive force which opposes the movement of slider  4 . 
         [0090]    This peak depends on the relative inclination of the surfaces, which is chosen so that slider  4  can be suitably actuated by probe  103 . 
         [0091]    The first of the two peaks mentioned above occurs, during opening of the connector, when surface  28  passes over surface  25 ; the second peak occurs during the closing phase, when surface  26  passes over surface  27 . 
         [0092]    The longitudinal distance between the end  22  and the projection  23  when the connector  1  is in the bottom closed configuration, namely the travel movement which probe  103  must perform between the bottom closed position and the position where the abovementioned peak may be detected, must be such as to satisfy a condition clarified below. 
         [0093]    Since, when the projection  23  is passed over, a peak value in the force is reached and this force, applied to slider  4 , opposes the movement of probe  103 , it is important that this force does not cause disengagement of slider  4  from probe  103 , namely that the bottom portion  6  should be able to maintain its grip on probe  103 . 
         [0094]    When probe  103  moves towards the centre of container  100 , the force, which probe  103  may apply on slider  4  depends or, the engagement of the upper end  109  against the base  16  of slider. In this case, there is therefore no risk of the probe being able to disengage from seat  10 . 
         [0095]    In this case, the upper portion  20 ) of slider  4 , which has a conical shape, tends to open, producing interference with the inner wall of the upper portion  19 . 
         [0096]    When probe  103 , however, is moving from the centre of the container  100  towards its mouth, the force which probe  103  may apply on slider  4  depends on the engagement of the bottom portion  8  inside the retaining groove  104 . Since the bottom portion  8  of slider  4  is deformable radially outwards, the force pulse produced as a result of passing over projection  23  could be greater than the opposing force which may be generated by the sole resistance to radial expansion of bottom portion  8  of slider  4 . 
         [0097]    It is therefore possible to design connector  1  so that the bottom portion  8  of slider  4  is situated inside the sleeve  9  when the upper portion  20  of slider  4  passes over the projection  23 , as can be seen in  FIG. 3   b.    
         [0098]    In this way, radial expansion of the bottom portion  8  is prevented by the presence of the sleeve  9 ; moreover, the conical form of the upper portion  20  of slider  4  and the projection  23  are such that, as a result of passing over the projection  23 , the cone of the upper portion  20  tends to close. This reduces friction with the inner wall of the upper portion  19  and the axial force which opposes longitudinal sliding of slider  4  and, consequently, also the axial force which tends to open the bottom portion  8 . 
         [0099]    In other words, the longitudinal distance between second abutment surface  18  and sixth abutment surface  28  may be advantageously greater than the longitudinal extension of the bottom portion  8  and less than the longitudinal distance between the first abutment surface  17  and third abutment surface  25 . 
         [0100]    Main body  3  and slider  4  may be both made of a single piece of polymer material, preferably by means of moulding. 
         [0101]    Obviously a person skilled in the art, in order to satisfy contingent and specific requirements, may make numerous modifications and variations to the configurations described above, all of which are contained, moreover, within the scope of protection of the invention as defined by the following claims.
The present invention concerns a connector ( 1) able to be mounted on the neck of a container for liquids ( 100), in the form of a bottler consisting of a main body having, sliding longitudinally therein, a slider provided with a radially expandable bottom portion so as to engage reversibly with a hollow:, probe, in which the hollow probe is able to perform the longitudinal displacement of the the slider and connect the inside of the container ( 100) with its interior so as to allow the dispensing of liquid from the container.