Abstract:
The invention relates to a measuring cap ( 1 ) for a pressurised container ( 2 ), comprising: a body ( 8 ) having an axial fluid channel ( 12 ), shaped in order to be inserted into the container ( 2 ) through the neck ( 5 ); a sealing joint ( 15 ) shaped bear on a portion of the body ( 8 ); an assembly ring ( 16 ) which is used for removably securing the measuring cap ( 1 ) to the container ( 2 ) and which is removable; and a closure member ( 17 ) for selectively closing and opening the fluid outlet channel ( 12 ).

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    The present invention concerns pressurised receptacles able to contain a fluid, and more particularly the means of closing such pressurised receptacles. 
         [0002]    Known pressurised receptacles are of the aerosol type. 
         [0003]    An aerosol is a set of solid or liquid particles of a chemical substance given in suspension in a gaseous medium. 
         [0004]    In normal life, the term “aerosol” also designates the receptacle containing a mixture of a product and a propellant gas. The propellant gas creates a pressure inside the receptacle. By opening an outlet valve, the mixture is expelled outside the pressurised receptacle. The product is atomised in the form of an aerosol, that is to say in fine particles in suspension in air. 
         [0005]    The propellant gas is normally nitrogen since it is an inert gas and therefore less dangerous than propane, butane and other flammable hydrocarbons, which do not however have an effect on the ozone layer. 
         [0006]    A known aerosol receptacle comprises a bottom, a lateral wall and a neck, and is usually produced from aluminium. The thickness of the receptacle is designed to withstand up to 18 bar pressure inside. There exist such aerosol receptacles having various capacities. 
         [0007]    Such receptacles are described in particular in the documents U.S. Pat. No. 3,977,576, FR 2909981 A1, U.S. Pat. No. 6,253,970 B1 and U.S. Pat. No. 3,187,962. 
         [0008]    These known receptacles are closed by a dispensing valve designed to be non-removable. The receptacles cannot therefore be reused. When a pressure is applied to an operating member connected to the dispensing valve, the seal is broken, enabling the product contained in the receptacle to pass into the valve and to escape to the outside of the receptacle. 
         [0009]    Aerosols, that is to say the pressurised receptacles provided with a non-removable dispensing valve, are governed by very strict and draconian safety standards. In all known aerosols, the dispensing valves are not removable and they do not make it possible to effectively measure out the flow of product emerging from the pressurised receptacle. The internal pressure allowed by the standards is limited to 12 bar at 50° C. In addition, the filling of known aerosols is limited by strict standards to 66% of the volume, which is itself a maximum of one litre. 
         [0010]    Known aerosols function only when they contain a non-granular fluid, otherwise the dispensing valve becomes blocked and the aerosols can no longer dispense fluid. 
       DISCLOSURE OF THE INVENTION 
       [0011]    A first problem proposed by the present invention is to design a closure means for a pressurised receptacle able to contain a fluid that is removable and makes it possible to measure out the emerging product, and the safety in use of which is ensured up to pressures of more than 20 bar. 
         [0012]    A second problem that is at the basis of the present invention is to design a pressurised receptacle that allows an intermittent thrust and can contain and dispense even a granular fluid. 
         [0013]    Because aerosols do not function with a granular fluid, aerosol valves do not make it possible to solve these problems. 
         [0014]    The idea that is at the basis of the invention is to design a reliable removable measuring cap and to use it in association with a receptacle containing a fluid at a pressure appreciably greater than the pressures normally allowed for aerosols, for example around 30 bar. 
         [0015]    To achieve these aims as well as others, the invention proposes, according to a first aspect, a measuring cap for a pressurised receptacle able to contain a fluid, the receptacle comprising a bottom and a substantially cylindrical lateral wall that narrows towards a neck having a front neck face and an internal neck edge, comprising:
       a body with a longitudinal axis having:
           a penetrating part, which is conformed so as to enter the neck of the receptacle and comprises a radial peripheral protrusion able to engage in abutment against the internal edge of the neck,   an emerging part, with an axial fluid passage communicating with the inside of the receptacle and communicating with the outside of the receptacle through a fluid outlet passage,   a sealing shoulder at the junction between the penetrating part and the emerging part,   
           a sealing joint, conformed so as to bear on the sealing shoulder and on the front neck face,   an assembly ring able to be fixed removably to the emerging part of the body while axially clamping the first sealing joint against the front neck face and against the sealing shoulder, and   a closure member able to selectively close and open the fluid outlet passage, controlled by an operating member accessible on the emerging part of the body.       
 
         [0023]    Such a measuring cap is removable. Thus the receptacle that it closes can easily be reused, which reduces the quantity of waste produced. Such a measuring cap is therefore ecological. Such a measuring cap does not comprise a valve. And the pressurised receptacle provided with such a removable measuring cap is not constrained by the strict aerosol standards, nor by other rules if the volume of the receptacle is less than one litre and the pressure produced per volume is less than 50 bar/litre. 
         [0024]    This measuring cap is simple in design; it comprises only three main elements that can be preassembled, and a fourth element to be assembled in order to connect the measuring cap to the pressurised receptacle. It is therefore also simple to use. 
         [0025]    Such a measuring cap is compatible with conventional receptacle bodies for aerosols so that it is possible to profit from the low cost of these mass-produced receptacles. 
         [0026]    In addition, the cap according to the invention is a measuring cap and the user can therefore choose the rate of flow of product out of the pressurised receptacle. 
         [0027]    Advantageously, it is possible to provide for the radial peripheral protrusion to comprise a frustoconical portion, the cone angle of which corresponds substantially to the inclination of the internal neck edge of the receptacle. 
         [0028]    The mechanical thrust forces on the neck of the receptacle are thus best distributed. 
         [0029]    Advantageously, provision can be made for the penetrating part to comprise at least one recessed lateral face defining a width less than the diameter of the neck of the receptacle. 
         [0030]    The introduction of the body into the pressurised receptacle is thus facilitated. 
         [0031]    Provision can advantageously be made for said at least one lateral face to be positioned so that it allows a slight local deformation of the neck that generates a leakage beyond a predetermined pressure inside the receptacle. 
         [0032]    This is an inexpensive safety element that is easy to implement. 
         [0033]    Provision can advantageously be made for the measuring cap to be produced from metal or plastics material. 
         [0034]    The use of plastics material reduces the manufacturing costs of the measuring cap since plastics material is less expensive than metal. However, metal will have better mechanical strength. 
         [0035]    In the case of a metal measuring cap, provision can advantageously be made for the metal to be stainless steel or an aluminium alloy. 
         [0036]    These metals are widespread and forming thereof by numeric control or any other means is well known. 
         [0037]    Advantageously, provision can be made for the assembly ring to be fixed to the body by screwing, pressing or cottering. 
         [0038]    These types of assembly make it possible to obtain a measuring cap that is removable. 
         [0039]    Advantageously, provision can be made for the penetrating part of the body to comprise two lateral flats on either side of the longitudinal axis of the body. One of these two flats producing the lateral face. 
         [0040]    Provision can advantageously be made for the assembly ring to comprise a peripheral skirt surrounding the neck of the receptacle, leaving a leakage space between its end edge and the peripheral wall of the receptacle. 
         [0041]    This is an inexpensive safety element that is easy to implement, which guides away from the user the jet of fluid emerging from the receptacle through the sealing joint in the event of overpressure. 
         [0042]    By surrounding the neck of the receptacle, the assembly ring also fulfils the function of reinforcement of the neck, opposing the action of the internal pressure of the receptacle, which tends to enlarge the neck. 
         [0043]    Advantageously, provision can be made, according to a first embodiment, for the closure member to be a rod slidably mounted in the axial fluid passage between a closure position and an open position, and comprises two annular grooves able to receive annular closure joints. 
         [0044]    The travel of the closure element is limited between two predefined positions. This prevents any risk of the closure element leaving the axial fluid passage unexpectedly. 
         [0045]    According to a second embodiment, provision can advantageously be made for the closure member to be a locking screw that is actuated by screwing or unscrewing in the body. 
         [0046]    The penetration of the locking screw in the body is chosen precisely by a user by screwing this locking screw to a greater or lesser extent. And the structure is well suited to applications in which the fluid contains powders or solid suspensions. 
         [0047]    Provision can advantageously be made for the closure member also to comprise a closure element positioned in the axial fluid passage close to the neck of the receptacle and held distant from the latter by a spring or by the internal pressure of the receptacle. 
         [0048]    The closure element fulfils a dual function, namely the valve function during filling and the safety element function. 
         [0049]    According to a second aspect, the invention provides a receptacle able to contain a pressurised fluid, closed by a measuring cap according to first aspect of the invention, and having an initial internal pressure greater than 20 bar. 
         [0050]    Such a receptacle does not need to comply with aerosol standards since it does not comprise a fixed valve and the cap is removable. 
     
    
     
       SUMMARY DESCRIPTION OF THE DRAWINGS 
         [0051]    Other objects, features and advantages of the present invention will emerge from the following description of particular embodiments, given in relation to the accompanying drawings, among which: 
           [0052]      FIG. 1  is a view in longitudinal section of a pressurised receptacle provided with a measuring cap according to a first embodiment of the invention; 
           [0053]      FIG. 2  is an exploded view of the elements to be assembled for producing the measuring cap of  FIG. 1 ; 
           [0054]      FIG. 3  is a side view of the body of the measuring cap of  FIG. 1  in a state in which it has entered the neck of the receptacle; 
           [0055]      FIG. 4  is an enlarged view in longitudinal section of the measuring cap of  FIG. 1 ; 
           [0056]      FIG. 5  is a view in longitudinal section of the measuring cap of  FIG. 1  in a closed position; 
           [0057]      FIG. 6  is a view in longitudinal section of an enlargement at the annular groove of the measuring cap of  FIG. 1  in an intermediate position; 
           [0058]      FIG. 7  is a view in longitudinal section of the cap of  FIG. 1  in an open position; 
           [0059]      FIGS. 8 and 9  are views in longitudinal section of a pressurised receptacle provided with a measuring cap according to a second embodiment; 
           [0060]      FIGS. 10 and 11  are views in longitudinal section of a pressurised receptacle provided with a measuring cap according to a third embodiment. 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0061]      FIGS. 1 to 7  illustrate a first embodiment of the invention, in which a measuring cap  1  is connected by screwing to a pressurised receptacle  2 . The numerical references therefore refer to the same elements in all these figures. 
         [0062]      FIG. 1  illustrates the receptacle  2  closed by the measuring cap  1 . 
         [0063]    The receptacle  2  comprises a bottom  3  and a cylindrical lateral wall  4  that narrows towards a neck  5 . The narrowing is provided at an angle of inclination p. The neck  5  is produced by an outward folding on itself of the material constituting the receptacle  2 . The neck  5  comprises a front neck face  6  and a bottom neck edge  7 . The receptacle  2  is designed to contain a pressurised fluid. 
         [0064]    To describe the measuring cap  1 ,  FIG. 4  is considered, which illustrates more precisely in section the elements making up the measuring cap  1 . 
         [0065]    The measuring cap  1  comprises a body  8  with a longitudinal axis I-I, a sealing joint  15 , an assembly ring  16 , a closure member  17  and an operating member  18 . 
         [0066]    The body  8  comprises a penetrating part  9  and an emerging part  11 , which join at a sealing shoulder  14  oriented towards the emerging part  11 . 
         [0067]    The penetrating part  9  comprises a substantially cylindrical distal part and a radial peripheral proximal protrusion  10 . The radial peripheral protrusion  10  comprises a frustoconical portion  10   a  ( FIG. 2 ) with a cone angle α. 
         [0068]    The cone angle α is designed to correspond to the angle of inclination β so as to distribute the mechanical forces of the measuring cap  1  on the receptacle  2 . 
         [0069]    The penetrating part  9  comprises two lateral flats  19   a  and  19   b  ( FIGS. 2 and 3 ) on either side of the longitudinal axis I-I of the body  8 . These two lateral flats  19   a  and  19   b  ( FIGS. 2 and 3 ), parallel to the longitudinal axis I-I, are designed to enable the penetrating part  9  of the body  8  to be introduced into the receptacle  2  through the neck  5 . 
         [0070]    To do this, the width  190  of the penetrating part  9 , at the two lateral flats  19   a  and  19   b , is designed to be less than the diameter D of the neck  5  of the receptacle  2 . 
         [0071]    As an alternative, the penetrating part  9  of the body  8  can comprise non-parallel, non-symmetrical lateral faces, or a single lateral face. The main thing is to enable the penetrating part  9  to enter the neck  5  and to afford a sufficient surface for the sealing joint  15 . 
         [0072]    The emerging part  11  comprises a through axial fluid passage  12 , a fluid outlet passage  13  and a threaded portion  11   a  on its external surface close to the sealing shoulder  14 . The fluid outlet passage  13  and the axial fluid passage  12  communicate with each other in order, once the measuring cap  1  is connected to the receptacle  2 , to enable the product contained in the receptacle  2  to flow. 
         [0073]    The axial fluid passage  12  comprises an intermediate shoulder  30  disposed in an intermediate position between the fluid outlet passage  13  and the upstream orifice  12   a  of the axial fluid passage  12  and having its face oriented in the upstream direction. 
         [0074]    The sealing joint  15  is annular and is conformed so as to bear on the sealing shoulder  14  and on the front neck face  6 . 
         [0075]    The assembly ring  16  comprises a substantially cylindrical portion  25  having a threaded through opening  24  and a peripheral skirt  20 . The thread of the threaded through opening  24  of the assembly ring  16  is designed to correspond to the thread of the threaded portion  11   a  of the emerging part  11 . 
         [0076]    The closure member  17  is able to selectively close and open the fluid outlet passage  13 . It is controlled by an operating member  18  accessible on the emerging part  11  of the body  8 . 
         [0077]    The closure member  17  is a rod comprising two annular grooves  22   a  and  22   b  with a frustoconical profile and offset longitudinally from each other at a separation greater than the axial separation between the fluid outlet passage  13  and the intermediate shoulder  30  ( FIG. 4 ). 
         [0078]    Each annular groove  22   a  and  22   b  is provided with a closure joint, respectively  23   a  and  23   b . Each closure joint  23   a  and  23   b  can advantageously be made from elastomer and be cylindrical and tubular in shape with a circular cross section of constant thickness. The upstream annular groove  22   a  has a depth that decreases in the direction of the upstream orifice  12   a.    
         [0079]    The closure member  17  comprises an intermediate portion  170  situated between the two annular grooves  22   a  and  22   b  and is cylindrical in the embodiment in  FIGS. 1 to 7 . This intermediate portion  170  could however be frustoconical, or more widely any shape to be determined according to the granulometry of the fluid to be dispensed. 
         [0080]      FIGS. 5 to 7  illustrate the sliding of the closure member  17  in the axial fluid passage  12 . 
         [0081]      FIG. 5  illustrates the measuring cap  1  in a closure position P 1  in which the product contained in the receptacle  2  cannot be expelled to the outside of the receptacle  2 : the upstream closure gasket  23   a  is engaged in a cylindrical portion with a small diameter of the axial fluid passage  12 , between the fluid outlet passage  13  and the intermediate shoulder  30 , and then provides sealed closure of the axial fluid passage  12 . 
         [0082]      FIG. 6  illustrates the closure member  17  to a larger scale in an intermediate position P. In this intermediate position P, the upstream closure joint  23   a  is in line with the intermediate shoulder  30  and produces a partial opening allowing the pressurised fluid to pass at a rate that the user can control by axial movement of the closure member  17 . The frustoconical form of the annular groove  22   a  gradually forces the upstream closure joint  23   a , which allows gradual opening. 
         [0083]      FIG. 7  illustrates the measuring cap  1  in an open position P 2 , in which the product contained in the receptacle  2  is expelled to the outside of the receptacle  2 . 
         [0084]    As illustrated in  FIG. 5 , when the closure member  17  is in the closure position P 1 , the fluid cannot be expelled since the axial fluid passage  12  is closed off by the closure member  17 . Through the pressure inside the receptacle  2 , the closure member  17  is pushed outwards, and its travel is limited by a shoulder  26  provided on the closure member  17  and which bears axially against the intermediate shoulder  30  of the axial fluid passage  12 , preventing the closure member  17  escaping. 
         [0085]    The sealing is provided in the closure position P 1  by the upstream closure joint  23   a , which is pressed in a cone against the wall of the axial fluid passage  12 . 
         [0086]    In the event of overpressure inside the receptacle  2  beyond a given pressure value, leakage is possible through the sealing joint  15  and in the space E between the peripheral skirt  20  and the receptacle  2 . 
         [0087]    When a user applies a force F ( FIG. 7 ) on the operating member  18 , the rod of the closure member  17  slides in the axial fluid passage  12 . The fluid does not escape, because of the upstream closure gasket  23   a , which is always pressed against the wall of the axial fluid passage  12 . As will be understood from  FIG. 6 , the closure is provided effectively and very economically with a cylindrical closure joint  23   a  engaged in a frustoconical annular groove  22   a.    
         [0088]      FIG. 7  illustrates the elements in the open position P 2  in which the fluid is expelled. The closure member  17  is lowered sufficiently to break the seal at the upstream closure gasket  23   a.    
         [0089]    The fluid is therefore expelled in a controlled fashion towards the outside, passing through the axial fluid passage  12  and then the outlet passage  13 . The second closure gasket  23   b  provides the seal for preventing a quantity of fluid being able to be extracted towards the operating member  18 . 
         [0090]    The operating member  18  is a hood provided with a threaded bore  18   a  for fixing thereof by screwing on the threaded distal end  17   a  of the closure member  17 . As an alternative, the operating member  18  can be fixed by clipping, crimping, pooping or adhesive bonding. 
         [0091]    In the embodiment described, an elastic means  17   b  of the helical compression spring type is engaged between the operating member  18  and the body  8  in order to assist closure if the pressure is too low inside the receptacle  2 , or if the fluid is sticky. 
         [0092]    The elastic means  17   b  is however not essential and it can be considered that the pressure inside the receptacle  2  is sufficient to enable the closure member to slide as far as the closure position P 1  with suitable fluids to be dispensed. 
         [0093]    If necessary, the fluid contained in the receptacle must be previously filtered. 
         [0094]      FIG. 2  explains the order of assembly of these elements in order to produce the measuring cap  1 . 
         [0095]    The sealing joint  15  is arranged on the inside of the assembly ring  16  so that, once the whole is assembled, the sealing joint  15  makes the seal at the neck  5  of the receptacle  2 . The closure member  17  without the operating member  18  is slidably mounted in the axial fluid passage  12 , engaging it through the upstream orifice  12   a . The closure gaskets  23   a  and  23   b  will have been previously mounted in the respective annular grooves  22   a  and  22   b  provided in the closure member  17 . The assembly ring  16  provided with the gasket  15  is engaged on the body  8 . The operating member  18  is screwed on the distal end  17   a  of the closure member  17 , locking the closure member with respect to rotation by engagement of a screwdriver in a slot  17   c  provided at the proximal end of the closure member  17 . As an alternative to the slot  17   c , any other locking means can be provided, and the slot  17   c  can have any other profile. 
         [0096]    Next the penetrating part  9  can be introduced obliquely in the neck  5  of the receptacle  2 . This introduction is made possible in particular through the presence of the two lateral flats  19   a  and  19   b . Then the measuring cap  1  is positioned so that the radial peripheral protrusion  10  engages in abutment against the internal edge of the neck  7 . 
         [0097]    Then the assembly ring  16  is screwed on the threaded part of the emerging part  11  of the body  8 . The assembly ring  16  axially clamps the first gasket  15  against the front neck face  6  and against the sealing shoulder  14 . The connection of the measuring cap  1  with the receptacle  2  is effected. 
         [0098]    The peripheral skirt  20  surrounds the neck  5  of the receptacle  2 , leaving a leakage space E between its extreme edge  21  and the peripheral wall  4  of the receptacle  2 . 
         [0099]    The invention also ensures the safety of the users, through a safety leak when a predetermined maximum pressure is reached inside the receptacle  2 . To do this, the lateral flats  19   a  and  19   b  are positioned recessed so that they allow a slight local deformation of the neck  5 , producing an area of less strength. Thus, when the predetermined maximum pressure is reached, the neck  5  is deformed outwards and the gasket  15  is less crushed, which gives rise to a safety leakage. 
         [0100]    This first embodiment is particular suitable for fluids with a granulometry of less than 500 μm. 
         [0101]      FIGS. 8 and 9  illustrate a second embodiment of the present invention, in which the receptacle  2  ( FIG. 1 ) is closed by the measuring cap  100 . As in the first embodiment, the measuring cap  100  is connected to the receptacle  2  by screwing. 
         [0102]    The same essential means are marked by the same numerical references as in  FIGS. 1 to 7 . 
         [0103]    The measuring cap  100  comprises a body  80  with a longitudinal axis II-II, a sealing joint  15 , an assembly ring  16  and a closure element  40 . 
         [0104]    The main difference between the first and second embodiments lies in the fact that, in the second embodiment, the closure member  41  and the operating member  42  are in a single piece and produce the closure element  40 . As an alternative, the operating member  42  can be a part attached by adhesive bonding, clipping, hooping or screwing. 
         [0105]    The axial fluid passage  12  comprises a threaded top portion  12   b , a bottom shoulder  43  and an intermediate shoulder  44   a . The bottom shoulder  43  is placed in an intermediate position between the fluid outlet passage  13  and the upstream orifice  12   a  of the axial fluid passage  12 . 
         [0106]    The closure element  40  is able to selectively close and open the fluid outlet passage  13 . It is controlled directly by an action of a user on the operating member  42  accessible on the emerging part  11  of the body  80 . 
         [0107]    The closure member  41  is a rod comprising four sections. A first top section  41   a  is partially threaded in its part close to the operating member  42 . Its second portion  41   b  has a reduced diameter and comprises an annular groove  45  with a frustoconical double profile. 
         [0108]    The annular groove  45  may however have any other form producing a bulge, for example a spherical profile. 
         [0109]    The first portion  41   a  and the second portion  41   b  are joined by a shoulder  44   a . The third portion  41   c  has a frustoconical profile and joins the fourth portion  41   d  at a point that terminates the rod. 
         [0110]    The annular groove  45  is provided with a closure joint  46 . As in the previous embodiment, the closure joint  46  can advantageously be made from elastomer and be tubular and cylindrical in shape with a circular cross section with constant thickness. The annular groove  45  has a depth that increases in the direction of the upstream orifice  12   a.    
         [0111]    In this embodiment, the measuring cap  100  also comprises a closure element such as a ball  47 , engaged in axial movement in the axial fluid passage  12 , and held in position by a conical spring  48 . The diameter of the ball  47  is chosen so as to be sufficient in order not to enter the receptacle  2 , and sufficient to create a seal when the ball  47  is in contact with the bottom shoulder  43 . 
         [0112]    In an embodiment that is not illustrated, the spring could be straight and in abutment on the plunger tube  49  ( FIGS. 8 to 11 ), the inside diameter of which is less than that of the ball  47 . 
         [0113]    The functioning of the measuring cap  100  will now be described. 
         [0114]    In the position illustrated in  FIG. 9 , the measuring cap  100  is in a closure position in which the product contained in the receptacle  2  cannot be expelled to the outside of the receptacle  2 . The point-shaped fourth portion  41   d  of the closure member  41  cooperates with a narrowing  50  of the axial fluid passage  12 , upstream from the fluid outlet passage  13 . The narrowing  50  forms a seat against which the fourth portion  41   d  can come to bear, then providing a sealed closure of the axial fluid passage  12 . 
         [0115]    When the closure member  41  is in an intermediate position, the point-shaped fourth portion  41   d  no longer cooperates with the narrowing  50  of the axial fluid passage  12 . In this way a partial opening is produced, which allows the pressurised fluid to pass at a rate that the user can control by axial movement of the closure member  41  by screwing the closure element  40  to a greater or lesser extent. The point-shaped form of the fourth portion  41   d  allows gradual opening. 
         [0116]    In order to adapt the flow rate of the fluid according to the granulometry of the fluid to be dispensed, the diameter of the third portion  41   c  and the shape of the point  41   d  can be modified. 
         [0117]    In an open position, the product contained in the receptacle  2  is expelled to the outside of the receptacle  2  since the third portion  41   c  is no longer in contact with the narrowing  50  of the axial fluid passage  12 , which has the effect of breaking the seal. 
         [0118]    When a user unscrews the closure element  40 , the rod of the closure member  41  rises in the axial fluid passage  12 . The closure seal  46 , which remains pressed against the wall of the axial fluid passage  12 , prevents the progress of the fluid towards the operating member  42 . 
         [0119]    The ball  47  fulfils the dual function of filling valve and safety valve. The function of the safety valve is illustrated in  FIG. 8 . 
         [0120]    For filling, the closure element  40  is absent, the fluid outlet passage  13  is blocked, and the ball  47  is pushed by the conical spring  48  towards the bottom shoulder  43 . By contact between the ball  47  and the bottom shoulder  43 , the seal is provided. 
         [0121]    During filling, the fluid entering under pressure pushes the ball  47  towards the inside of the receptacle  2  so that the ball  47  is no longer in contact with the bottom shoulder  43  and allows the pressurised fluid to pass towards the inside of the receptacle  2 . 
         [0122]    The ball  47  fulfils the role of non-return valve in that it prevents the fluid contained in the receptacle  2  from emerging since the fluid that moves towards the outlet pushes the ball  47  in contact with the bottom shoulder  43 , creating the seal and preventing the expulsion of pressurised fluid towards the outside of the receptacle  2 . 
         [0123]    The ball  47  also fulfils the role of safety valve since, if the closure  40  element is unscrewed by accident, the ball  47  rises and comes into contact with the bottom shoulder  43  in order to create the seal. The pressurised fluid is then not expelled to the outside of the receptacle  2 . 
         [0124]      FIGS. 10 and 11  illustrate a third embodiment of the invention. The difference compared with the second embodiment is the absence of a conical spring. The ball  47  is held in position by sufficient pressure inside the receptacle  2  ( FIG. 10 ). 
         [0125]      FIGS. 8 to 11  illustrate a plunger tube  49  for guiding the fluid from the inside of the receptacle  2  to the outside. 
         [0126]    The ball  47  has a diameter greater than the inside diameter after fitting of the plunger tube  49 , so that the ball  47  does not fall into the receptacle  2  ( FIG. 11 ). In this way, the ball  47  is engaged between the plunger tube  49  and the bottom shoulder  43 . 
         [0127]    The plunger tube  49  is not shown in  FIGS. 1 to 7  but can be designed to fulfil in particular the same function of limitation of the travel of the ball  47 , or the function of support of the spring  48 . 
         [0128]    In the embodiments in  FIGS. 8 to 11 , provision can advantageously be made for the cone of the needle  41   d  to have an angle of approximately 60°, and the needle is truncated so as to not to damage the ball  47  when the needle  41   d  is in contact with ball  47 . 
         [0129]    The second and third embodiments are suitable particularly for fluids with a granulometry of less than 2 mm. 
         [0130]    The measuring cap can be produced from any material having food characteristics when the receptacle must contain and dispense a fluid for food use. It can be produced from plastics material or metal (for example stainless steel or an aluminium alloy). 
         [0131]    The fluid outlet  13  could have any form enabling an extension tube to be fitted for dispensing the fluid more ergonomically. 
         [0132]    In an embodiment that is not illustrated, the cone angle α of the frustoconical portion of the radial peripheral protrusion  10  does not correspond to the inclination β of the internal edge of the neck of the receptacle. Thus when the penetrating part  9  is rotated an undercut is created and locks the body  8  firmly. 
         [0133]    In another embodiment that is not illustrated based on the embodiments in  FIGS. 8 to 11 , the ball  47  could be replaced by a cylinder with a diameter substantially less than the diameter of the axial fluid passage  12  and substantially greater than the inside diameter of the spring  48 , where applicable. Said cylinder can be provided with a substantially frustoconical groove, like the groove  22   a  ( FIG. 6 ). A closure joint, like the closure joint  23   a , is provided in the groove. The seal is achieved as illustrated in  FIG. 6 , the sealing joint coming into contact with a narrowing of the axial fluid passage, such as the narrowing  50  ( FIGS. 8 to 11 ). 
         [0134]    The present invention is not limited to the embodiments that have been explicitly described but includes the various variants and generalisations contained in the field of the following claims.