Abstract:
An assembly for packaging and dispensing liquid may include a receptacle for containing a supply of liquid and a refillable unit arranged to be placed in a separable manner on the receptacle. The refillable unit may include a body and a piston that is movable relative to the body and that co-operates therewith to define a storage chamber of variable volume for containing the liquid. The storage chamber may be put into fluid communication with the receptacle to be filled therefrom when the refillable unit is placed on the receptacle. The refillable unit may also include a pump arranged to take liquid from the receptacle when the refillable unit is placed thereon, and to take liquid from the storage chamber when the refillable unit is separate from the receptacle. The pump may include a pump chamber that is distinct from the storage chamber.

Description:
[0001]     This non-provisional application claims the benefit of French Application No.04 04207 filed on Apr. 21, 2004 and U.S. Provisional Application No. 60/569,246 filed on May 10, 2004, the entire disclosures of which are incorporated by reference herein. 
     
    
     BACKGROUND  
       [0002]     The present invention relates to an assembly for packaging and dispensing liquid, for example cosmetics, including care products.  
         [0003]     As used throughout this application, the term “cosmetic” is used to designate a cosmetic product as defined in the Jun. 14, 1993 Directive 93/35/EEC amending Directive 76/768/EEC.  
         [0004]     Patent application FR 2 773 443 discloses a refillable atomizer spray comprising a body that defines a chamber for storing liquid. The atomizer further comprises a piston slidably received in the body and capable of being pressed down to reduce the volume of the chamber and dispense the liquid. The quantity of substance that is dispensed depends on the length of the depression stroke of the piston with the chamber being completely emptied when the piston is depressed over its full stroke. Such an atomizer does not facilitate dispensing an accurate quantity of liquid corresponding to a fraction of the maximum volume of the chamber.  
         [0005]     Patent application FR 2 705 039 describes a dispenser device comprising a receptacle that contains a supply of liquid and is fitted with a first pump, and a refillable flask fitted with a second pump. The flask can be refilled with liquid via the first pump. To dispense the liquid contained in the flask, the user separates the flask from the receptacle and then actuates the second pump.  
         [0006]     Patent application FR 2 813 291 describes a system for filling a secondary flask from a main flask. The main flask is fitted with tubes enabling the main and secondary flasks to be put into fluid communication. When the secondary flask is fitted with a pump, the pump must be removed before interconnecting the main and secondary flasks for refilling.  
         [0007]     Patent application FR 2 802 447 describes a refillable spray system comprising a tank and a spray fitted with a pump. The tank and the spray are provided with ducts suitable for being temporarily interconnected to enable the spray to be refilled. The duct extending into the spray is open at a top end thereof to allow the liquid to flow directly into the tank of the spray system.  
         [0008]     Patent application FR 2 556 091 describes a removable refillable device comprising a body and a piston slidably received in the body. That device does not include a pump.  
       SUMMARY  
       [0009]     Exemplary embodiment of the present invention seek to provide a packaging and dispensing assembly which has a structure that is relatively simple and which enables liquid to be dispensed in relatively precise manner.  
         [0010]     Exemplary embodiment of the present invention thus may provide an assembly for packaging and dispensing liquid, the assembly comprising: a receptacle for containing a supply of a liquid; and a refillable unit arranged to be placed in a separable manner on the receptacle. The refillable unit may comprise: a body and a piston that is movable relative to the body and that co-operates therewith to define a storage chamber of variable volume for containing the liquid, and a pump arranged to take liquid from the receptacle when the refillable unit is placed thereon, and to take liquid from the storage chamber when the refillable unit is separate from the receptacle. The storage chamber may be put into fluid communication with the receptacle to be filled therefrom when the refillable unit is placed on the receptacle. The pump may include a pump chamber that is distinct from the storage chamber, that is, that does not coincide therewith. The storage chamber may be formed under the piston when the refillable unit is observed in a head-up position.  
         [0011]     In exemplary embodiments, when the refillable unit is used separately from the receptacle, one or more measured quantities of liquid may be dispensed relatively accurately, each quantity corresponding to a fraction only of a maximum volume of the storage chamber. The quantity dispensed may be determined by a maximum volume of the pump chamber, where the maximum volume of the pump chamber is smaller than the maximum volume of the storage chamber.  
         [0012]     In exemplary embodiments, the pump may also be used to take liquid from the supply of liquid in the receptacle.  
         [0013]     In embodiments in which the receptacle includes an outlet orifice arranged to be put into fluid communication with the storage chamber of a refillable unit for refilling purposes, the receptacle need not include have a pump that feeds the outlet orifice with liquid. The structure of the receptacle may thus be relatively simple.  
         [0014]     Thus, exemplary embodiments of the invention may include only one pump, that of the refillable unit, thus enabling costs to be reduced.  
         [0015]     Advantageously, the refillable unit may be arranged to enable suction to be generated in the storage chamber, at least when the storage chamber is in fluid communication with the receptacle, so as to enable the storage chamber to be filled.  
         [0016]     In exemplary embodiments, the pump chamber may be isolated from the storage chamber, at least while the liquid is being dispensed by the pump.  
         [0017]     In exemplary embodiments, the pump may include a suction orifice that is disposed close to an outlet orifice of the receptacle, for example, vertically in registration with the outlet orifice, when the refillable unit is placed on the receptacle.  
         [0018]     Thus, in such embodiments, the liquid leaving the receptacle via the outlet orifice may flow toward the suction orifice of the pump following a path that is relatively short, thereby limiting head losses.  
         [0019]     In exemplary embodiments, the pump may comprise an “airless” pump, that is, a pump without any air intake. The pump may be with or without precompression.  
         [0020]     In exemplary embodiments, the receptacle may include a support arranged to receive the refillable unit. The support may be held stationary relative to a remainder of the receptacle, for example. The support may be constituted by a separate part or may be made monolithically with the receptacle.  
         [0021]     In exemplary embodiments, the refillable unit and the receptacle may include respective fastener portions that co-operate in a releasable manner, for example, by snap-fastening, screw-fastening, bayonet-type fastening, by friction, or in some other way. This allows the refillable unit to be secured to the receptacle while the storage chamber is being filled and/or while the pump of the refillable unit is being used to take liquid from the receptacle.  
         [0022]     Advantageously, at least one of the refillable units and the receptacle may include portions in relief that co-operate with the other of the refillable unit and the receptacle to isolate a suction orifice of the pump in a leakproof or leaktight manner from outside, at least when the refillable unit is used to take liquid from the receptacle.  
         [0023]     In exemplary embodiments, the receptacle may include an air intake passage that allows air to be taken in when the pump of the refillable unit is used to take the liquid from the receptacle.  
         [0024]     In other exemplary embodiments, the receptacle does not include an air intake. In such embodiments, the receptacle may include, for example, a piston or a bag in contact with the liquid. For example, the receptacle may have a piston that moves in response to liquid being extracted from the receptacle. For example, the liquid may alternatively be contained in a flexible bag.  
         [0025]     In exemplary embodiments, when the refillable unit is placed on the receptacle so that the pump may take liquid therefrom, a volume of the storage chamber may preferably be at a minimum, for example being substantially zero. In such embodiments, the pump may communicate with a dip tube of the receptacle, for example.  
         [0026]     In exemplary embodiments, the piston may include an orifice that puts the receptacle into fluid communication with the storage chamber.  
         [0027]     In exemplary embodiments, the piston may advantageously have a shape that substantially matches an outside shape of the pump. This may make it possible to reduce a quantity of liquid remaining in the refillable unit when the volume of the storage chamber is at its minimum.  
         [0028]     In exemplary embodiments, the refillable unit may include a check valve disposed in the orifice of the piston. The check valve may be movable between a first position in which the check valve closes the orifice of the piston, and a second position in which the check valve allows liquid to flow through the orifice. The check valve may comprises a body with an inside passage.  
         [0029]     In exemplary embodiments, the check valve may comprise a ball. In such embodiments, the refillable unit may include a resilient return member arranged to apply a force on the ball, tending to return the ball into the closed first position.  
         [0030]     In exemplary embodiments, the piston may include a fastener portion that co-operates in a releasable manner, for example, by screw-fastening or snap-fastening, with a fastener portion of the receptacle when the refillable unit is placed on the receptacle.  
         [0031]     In exemplary embodiments, the piston may include a skirt defining a passage in communication with an orifice of the piston. The skirt may include the fastener portion, for example.  
         [0032]     In exemplary embodiments, the piston may include substantially coaxial inner and outer skirts. In such embodiments, the fastener portion may be provided on the outer skirt, and the inner skirt may define, for example, a passage in communication with an orifice of the piston.  
         [0033]     In exemplary embodiments, the receptacle may include a central portion that engages in the body of the refillable unit when said refillable unit is placed on the receptacle. In such embodiments, the central portion may include a fastener portion that co-operates with a fastener portion of the piston. The central portion may serve to fasten a dip tube, for example.  
         [0034]     In exemplary embodiments, the receptacle may contain a liquid comprising a cosmetic or a care product. For example, the receptacle may contain a perfume. The liquid may also comprise a cream, for example.  
         [0035]     Exemplary embodiments of the invention may also provide a refillable unit arranged to be placed in a separable manner on a receptacle. The refillable unit may comprise a body and a piston that is movable relative to the body and that co-operates therewith to define a storage chamber of variable volume for containing the liquid, and a pump arranged to take liquid from the receptacle when the refillable unit is placed on the receptacle, and to take liquid from the storage chamber when the refillable unit is separate from the receptacle. The storage chamber may be put into fluid communication with the receptacle to be filled therefrom when the refillable unit is placed on the receptacle. The pump may include a pump chamber that is distinct from the storage chamber. The storage chamber may be formed under the piston when the refillable unit is observed in a head-up position.  
         [0036]     In exemplary embodiments, the refillable unit may be arranged to enable suction to be generated in the storage chamber, at least when the storage chamber is in fluid communication with the receptacle, so as to enable the storage chamber to be filled under an effect of the suction.  
         [0037]     In exemplary embodiments, the volume of the pump chamber may be preferably smaller than the maximum volume of the storage chamber.  
         [0038]     In exemplary embodiments, the piston may include an orifice that puts the receptacle into fluid communication with the storage chamber.  
         [0039]     Exemplary embodiments of the invention may also provide a method of dispensing liquid, comprising: providing a packaging and dispenser assembly including a receptacle for containing a supply of liquid, and a refillable unit as described above; using the refillable unit to take one of liquid from the receptacle when the refillable unit is placed on the receptacle, and liquid from the storage chamber of the refillable unit when the refillable unit is separate from the receptacle; and dispensing a quantity of liquid taken by the refillable unit by actuating the pump over a full stroke. The quantity of liquid dispensed may correspond to a fraction only of a maximum volume of the storage chamber. For example, the fraction may be less than one-tenth thereof.  
         [0040]     In exemplary embodiments in which the pump includes a suction orifice and the receptacle includes an outlet orifice, the method may further comprise: putting the suction orifice into communication with the outlet orifice; and taking liquid from the receptacle.  
         [0041]     In exemplary embodiments in which the refillable unit includes a body and a piston sliding in the body, the method may further comprise: placing the refillable unit on the receptacle; and moving the piston relative to the body in order to increase the volume of the storage chamber, the piston moving away from the pump during this movement. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0042]     The present invention may be better understood on reading the following detailed description of non-limiting embodiments thereof, and on examining the accompanying drawings, in which:  
         [0043]      FIG. 1  is a diagrammatic and fragmentary view of an exemplary packaging and dispenser assembly;  
         [0044]      FIG. 2  is a diagrammatic and fragmentary axial section view of the assembly of  FIG. 1 ;  
         [0045]      FIG. 3  is a diagrammatic and fragmentary axial section view of the releasable unit of the assembly of  FIG. 2 , separated from the receptacle;  
         [0046]      FIG. 4  is a diagrammatic and fragmentary axial section view of the pump of the refillable unit of the assembly of  FIGS. 2 and 3 ;  
         [0047]      FIG. 5  is a diagrammatic and fragmentary axial section view of another exemplary packaging and dispenser assembly; and  
         [0048]      FIGS. 6 and 7  are diagrammatic and fragmentary axial section views of another exemplary packaging assembly in two different positions. 
     
    
     DETAILED DESCRIPTION OF EMBODIMENTS  
       [0049]      FIG. 1  shows an exemplary packaging and dispenser assembly  1 .  
         [0050]     The assembly  1  may comprise a receptacle  2  including a receptacle body  3  and a support  4  secured on the body  3 .  
         [0051]     The receptacle  2  may contain a supply of liquid.  
         [0052]     In the exemplary embodiment, the liquid may be a cosmetic, for example a perfume or some other low-viscosity liquid, for example, containing an alcohol-based solvent.  
         [0053]     In exemplary embodiments, the liquid may be a cream, for example, a care product, a lotion, or some other liquid for applying to a portion of the body or the face, including the hair.  
         [0054]     The support  4  may comprise: an assembly skirt  5  that enables the receptacle body  3  to be screw-fastened on the neck  6 ; a substantially cylindrical wall  8  of axis X forming a housing  9  for receiving a refillable unit  10 ; and a central portion  15  extending inside the housing  9 . The wall  8  may have a cross-section that may be circular, elliptical, or some other shape.  
         [0055]     In the exemplary embodiment, the assembly skirt  5  may be screw-fastened on the neck  6 . However, in other exemplary embodiments, the assembly skirt  5  may be secured in some other way, for example, by snap-fastening or crimping.  
         [0056]     Where appropriate or desired, at least one of the neck  6  and the support  4  may include antirotation means, for example, a portion in relief (not shown) that prevents the support  4  from turning relative to the receptacle  2 .  
         [0057]     The support  4  may be pressed against the neck  6  to prevent liquid escaping, while also leaving an air intake passage between the inside of the receptacle  2  and the outside.  
         [0058]     In other exemplary embodiments, the receptacle need not include an air intake between the inside and the outside.  
         [0059]     The wall  8  may have a cross-section that may be circular, elliptical, or some other shape.  
         [0060]     The central portion  15  may comprise a tubular wall  16  of axis X that may be slightly frustoconical, tapering upward, and that may be connected at a bottom end thereof to the wall  8  via a bottom wall  17 .  
         [0061]     In other exemplary embodiments, the wall  16  may have some other shape.  
         [0062]     A dip tube  99  may be secured in an inside space defined by the tubular wall  16 . The dip tube  99  may opens at a top end thereof to an outlet orifice  19  formed on the central portion  15 .  
         [0063]     Above the outlet orifice  19 , the top end of the central portion  15  may comprise a fastener portion  20  which, in the exemplary embodiment, may be provided with an annular bead  21 , the purpose of which is described below.  
         [0064]     Between the fastener portion  20  and the orifice  19 , the central portion may include an internal annular groove  22 .  
         [0065]     The refillable unit  10  may include a body  25  that may comprise a cylindrical wall  26  of axis X and a bottom wall  27 . The bottom wall  27  may be provided with an opening  28  that enables the central portion  15  to be inserted through said opening  28  when the refillable unit  10  is inserted in the housing  9  of the receptacle.  
         [0066]     At a bottom portion thereof, the body  25  may be provided with splines  30  that are parallel to the axis X and are designed to serve as abutments, as described further below.  
         [0067]     The refillable unit  10  may include a piston  32  that presses against an inside surface of the body  25  via bottom and top annular lips  33  and  34 .  
         [0068]     Together with the body  25 , the piston  32  may form a storage chamber  55  of variable volume above the piston  32 . The piston  32  may include a skirt  35  that extends beneath the lips  33  and  34 . The skirt  35  may define a passage  36  that puts a space situated above the piston  32  into communication with a space situated beneath the piston  32 .  
         [0069]     At a top portion thereof, the skirt  35  may include an inner annular bead  37 , and at a bottom portion thereof, may include an orifice  38  in which a check valve  39  is engaged.  
         [0070]     In the exemplary embodiment, the bottom of the skirt  35  may be connected to a fastener portion  42  including an annular groove  48  in which the annular bead  21  of the receptacle  2  may be engaged, for example, by snap-fastening.  
         [0071]     The check valve  39  may comprise a hollow body that defines an inside passage  45  of axis X. The passage may open at a top portion thereof to the outside via lateral openings  47 .  
         [0072]     On an outside surface thereof, the check valve  39  may include an annular bead  46  that snap-fastens in the groove  22  of the receptacle  2 , so as to provide a leaktight bearing between the check valve  39  and the central portion  15  of the receptacle  2 , and fastening therebetween.  
         [0073]     Additional annular beads  51  may be provided on the outside surface of the check valve  39  above the annular bead  46 , so as to come to press with a certain friction force against the inside surface of the skirt  35  when the check valve  39  is moved upward in the orifice  38 , so as to limit movement of the check valve  39  when the refillable unit  10  is in place on the receptacle  2 .  
         [0074]     The beads  51  may also enable the check valve  39  to be maintained in the closed position when the refillable unit  10  is used separately from the receptacle  2 , for example, to ensure that the refillable unit  10  is leaktight.  
         [0075]     The check valve  39  may be provided with a frustoconical top portion  49  that presses against a frustoconical surface  52  of the skirt  35 , so as to close the orifice  38  of the piston  5 , when the refillable unit  10  is separated from the receptacle  2 , as shown in  FIG. 3 .  
         [0076]     The refillable unit  10  may include a top wall  54  with an assembly skirt  56  secured in the body  25 .  
         [0077]     The skirt  56  may also serve to hold an airless pump  150  including a pump chamber  157 .  
         [0078]     The pump  150  may include a duct  162  that is relatively short compared to a height of the body  25 . A bottom end of the duct  162  may include a suction orifice  163 .  
         [0079]     As shown in  FIG. 4 , for example, the pump  150  may include a body  151  secured on the skirt  56 , for example, by snap-fastening.  
         [0080]     A control rod  152  may be mounted in the body  151  to slide against action of a return spring  153  working in compression. An endpiece  154  may be secured to a bottom end of the control rod  152 .  
         [0081]     A pushbutton  98  that serves both as an actuator member and as a dispenser member may be engaged as a force-fit on a top end of the control rod  152 , for example, as shown in  FIG. 2 .  
         [0082]     The control rod  152  may include an axial bore  158  that extends to a top end thereof and opens into the pump chamber  157  via radial orifices  155 .  
         [0083]     A piston  156  may be disposed to slide around the rod  152 . The piston  156  may co-operate with the body  151  to define the pump chamber  157 .  
         [0084]     The body  151  may form a seat for a ball  159  that, at rest, closes the orifice  163 .  
         [0085]     When the control rod  152  is at rest, the orifices  155  may be closed by the piston  156 .  
         [0086]     When a user presses on the pushbutton  98 , the control rod  152  may be depressed into the body  151 . At the beginning of its depression stroke, the piston  156  may not be driven by the control rod  152 . The control rod may thus move relative to the piston  156 , thereby releasing the orifices  155 . As the depression stroke of the control rod  152  continues, the control rod  152  may entrain the piston  156  downward. Liquid in the pump chamber  157  may then be compressed and may flow into the bore  158  via the orifices  155  to be dispensed.  
         [0087]     While the control rod  152  is moving downward, the ball  159  may remain pressed against its seat in a bottom of the body  151 , thereby isolating the pump chamber  157  from the storage chamber  55 .  
         [0088]     When the user releases the pushbutton  98 , the control rod  152  may begin by sliding in the piston  156  until coming into top abutment against the endpiece  154 .  
         [0089]     The axial bore  158  may then be isolated from the pump chamber  157  and continued upward movement of the control rod  152  under drive from the spring  153  may generate suction in the pump chamber  157 , which may be accompanied by the ball  159  lifting and liquid being sucked into the pump chamber  157 .  
         [0090]     The pump  150  may comprise some other structure without thereby going beyond the ambit of the present invention. For example, the ball  159  may be replaced by a suction check valve made of elastomer, for example.  
         [0091]     The piston  32  may have a shape that substantially matches an outside shape of the pump  150 , so that the volume of the storage chamber and the passage  36  is as small as possible when the piston  32  is completely raised.  
         [0092]     The orifice  163  may be situated remote from a top wall of the storage chamber  55 , so as to be immersed in liquid even when a layer of air is above the liquid in a top portion of the storage chamber  55 .  
         [0093]     In the exemplary embodiment, the skirt  35  may surround the duct  162  of the pump with a small amount of clearance, and the bead  37  may press against the pump  150  in a leaktight manner, for example.  
         [0094]     The assembly  1  may be used in various ways.  
         [0095]     For the purpose of taking and dispensing liquid contained in the receptacle  2 , the user may place the refillable unit  10  on the receptacle  2  so that the fastener portion  42  of the piston  32  becomes engaged on the fastener portion  21  of the central portion  15  of the receptacle  2 , for example, as shown in  FIG. 2 .  
         [0096]     The closure member  39  may be moved upward so as to free the lateral openings  47 , thereby enabling the inside passage  45  to communicate firstly with the passage  36  of the skirt  35 , and secondly with the outlet orifice  19  of the receptacle  2 .  
         [0097]     When the refillable unit  10  is secured on the receptacle  2 , the volume of the storage chamber  55  is at its minimum, the piston  32  being pushed until pressing against the pump  150 , the annular bead  37  presses in a leaktight manner against the duct  162  of the pump  150 , for example, as shown in  FIG. 2 .  
         [0098]     By pressing on the pushbutton  98 , the user may cause liquid contained in the pump chamber of the pump  150  to be dispensed.  
         [0099]     By releasing the pushbutton  98 , the pump  150  may suck in liquid contained in the receptacle  2 , the liquid flowing along a path passing via the dip tube  99 , the outlet orifice  19 , the inside passage  45  of the check valve, and the passage  36  of the skirt  35 .  
         [0100]     Additional pressure on the pushbutton  98  may enable the liquid sucked in this manner to be dispensed.  
         [0101]     To fill the storage chamber  55 , the user may move the body  25  of the refillable unit upward relative to the receptacle  2 , with the piston  32  remaining secured to the fastener portion  20  of the receptacle  2 .  
         [0102]     Thus, the piston  32  may slide downward relative to the body  25 , thereby generating suction in the storage chamber  55  that enables liquid contained in the receptacle  2  to be sucked in via the inside passage  45  of the closure member  39 .  
         [0103]     At an end of stroke, the bottom lip  33  of the piston  32  may press via a relatively stiff portion against the splines  30 , so that when the user continues to move the refillable unit  10  upward: the skirt  35  may be released from the central portion  15 , with the check valve  39  remaining secured to the central portion  15 ; then, the frustoconical portion  49  may press against the corresponding frustoconical surface  52  of the skirt  35 , so as to close the orifice  38 ; and then, the check valve  39  may be released from the central portion  15 .  
         [0104]     Such a sequence helps to ensure that the check valve  39  is in the closed position when the refillable unit  10  is removed.  
         [0105]     When the refillable unit  10  is separated from the receptacle  2 , the user may dispense the liquid contained in the storage chamber  55  by actuating the pump  150 .  
         [0106]     The piston  32  may rise in the body  25  as the storage chamber  55  empties.  
         [0107]     When the refillable unit  10  is partially full of liquid, putting the refillable unit  10  in place on the receptacle  2  may cause liquid that was contained in the storage chamber  55  to be expelled into the receptacle  2 , with the check valve  39  passing into the open position before the piston  32  becomes fastened on the central portion  15 .  
         [0108]     The invention is not limited to the exemplary embodiments described above.  
         [0109]      FIG. 5  shows an exemplary packaging and dispenser assembly  200  in accordance with another embodiment of the invention.  
         [0110]     The assembly  200  may include a refillable unit  10 ′ that is substantially similar to the refillable unit described above.  
         [0111]     The refillable unit  10 ′ may have a height that is shorter, and a cross-section that is greater than the refillable unit  10 .  
         [0112]     The refillable unit  10 ′ may be refilled by a receptacle  202  comprising a receptacle body  203  with a neck  206  on which a support  204  is secured, for example, by snap-fastening.  
         [0113]     For example, the support may comprise a tubular skirt  205  of axis X that extends above the neck  206  of the receptacle body  203  to receive the refillable unit  10 ′.  
         [0114]      FIGS. 6 and 7  show an exemplary packaging assembly  300  in accordance with another embodiment of the invention.  
         [0115]     The assembly  300  may include a receptacle  301  comprising a receptacle body  302  and a support  303  secured to the body  302 .  
         [0116]     The support  303  may comprise: an assembly skirt  304  that enables the receptacle body  302  to be screwed onto a neck  305 ; a transverse wall  307  that presses against the top segment of the neck  305 ; and a substantially cylindrical wall  308  of axis X that forms a housing  309  for receiving a refillable unit  310 .  
         [0117]     A major fraction of the wall  308  may extend beneath the transverse wall  307  when the assembly  300  is observed head-up, with the wall  308  forming a cylindrical portion  312  above the transverse wall  307 .  
         [0118]     The support  303  may further comprise a central portion  313  that extends into the housing  309  and comprises a substantially cylindrical wall  314  of axis X connected at a bottom end thereof to the wall  308  via a bottom wall  315 .  
         [0119]     At a top end thereof, the wall  314  may include a fastener portion  317  provided with a groove  318 , the purpose of which is described below.  
         [0120]     The central portion  313  may include an endpiece  319  that extends into an inside space defined by the wall  314 , with the endpiece  319  comprising a frustoconical wall  320  that is connected to the wall  314  beneath the fastener portion  317 .  
         [0121]     The frustoconical wall  320  may be extended by a cylindrical portion  322  of axis X that communicates at a top end thereof with an outlet orifice  323 .  
         [0122]     A dip tube  99  may be secured in the inside space defined by the portion  322 , with the dip tube  99  opening at a top end thereof to the outlet orifice  323 .  
         [0123]     The refillable unit  310  may include a body  330  comprising a tubular wall  331  of axis X with a return margin  332  at a bottom end thereof.  
         [0124]     The margin  332  may have an upwardly-tapering, slightly frustoconical shape with an annular edge  333 , and may have an inside diameter that is slightly smaller that the maximum diameter of the fastener portion  317 .  
         [0125]     The rim  333  may define an opening  335  that enables the central portion  313  to be inserted through the opening  335  when the refillable unit  310  is inserted into the housing  309  of the receptacle  301 .  
         [0126]     The refillable unit  310  may include a piston  337  which may co-operate with the body  330  to form a storage chamber  338  of variable volume above the piston  337 .  
         [0127]     The piston  337  may include outer and inner coaxial skirts  340 ,  341 , with the inner skirt  341  being connected to the inside surface of the outer skirt  342  substantially mid-way up the outer skirt, forming an opening  342  of substantially frustoconical shape that tapers downward.  
         [0128]     The piston  337  may include bottom and top annular lips  345 ,  346  connected to the outer skirt  340  and pressed against the inside surface of the body  330 .  
         [0129]     The outer skirt  340  may include a fastener portion  347  that includes an annular bead  348  arranged to become engaged by snap-fastening in the groove  318  of the fastener portion  317  of the receptacle  301  when the refillable unit  310  is inserted into the housing  309  of the receptacle.  
         [0130]     The inner skirt  341  may form a housing  350  arranged to receive a check valve, for example, comprising a ball  351 . The housing  350  may include a bearing surface  352  against which the ball  351  may be pressed to close a passage  353  defined by the inner skirt  341 .  
         [0131]     The refillable unit  310  may include a resilient return member  354  arranged to exert a force on the ball  351 , such force tending to press the ball  351  against the bearing surface  352  so as to close the passage  353 .  
         [0132]     In the exemplary embodiment, the resilient return member  354  may comprise a helical spring that, at one end, presses against the ball  351 , and at an opposite end, presses against the piston  337 .  
         [0133]     The annular bearing surface  352  may define an orifice  355  that may be put into fluid communication with the outlet orifice  323  of the receptacle.  
         [0134]     At a top end thereof, the body  330  may include a bead  357  that enables a pump  150  to be put in place by a fret  358 .  
         [0135]     The pump  150  may include a duct  162  that is arranged to engage in the passage  353  of the piston  337  via the opening  342 .  
         [0136]     The piston  337  may have a shape that substantially matches an outside shape of the pump  150 .  
         [0137]     The assembly  300  may be used in various ways.  
         [0138]     For the purpose of taking and dispensing the liquid contained in the receptacle  301 , the user may place the refillable unit  310  on the receptacle  301  so that the fastener portion  347  of the refillable unit  310  becomes engaged on the fastener portion  317  of the receptacle by inserting the bead  348  in the groove  318 , for example, as shown in  FIG. 6 .  
         [0139]     The inner skirt  341  of the piston  337  may be pressed in a leaktight manner against the endpiece  319  of the receptacle.  
         [0140]     The ball  351  may be displaced by pressing upward against the endpiece  319 , against the force exerted by the spring  354 , so as to move away from the bearing surface  352  and open the orifice  355 .  
         [0141]     When the refillable unit  310  is secured on the receptacle  301 , the volume of the storage chamber  338  may be at its minimum, with the piston  337  being pushed until coming to press against the pump  150 .  
         [0142]     The pump  150  may be pressed in a leaktight manner against the piston  337 .  
         [0143]     By pressing on the pushbutton  98 , the user may cause liquid contained in the pump chamber of the pump  150  to be dispensed.  
         [0144]     By releasing the pushbutton  98 , the pump  150  may suck in liquid contained in the receptacle  301 , the liquid flowing along a path passing via the dip tube  99 , the outlet orifice  323 , and the passage  353  of the skirt  341 .  
         [0145]     To fill the storage chamber  338 , the user may move the body  330  of the refillable unit upward relative to the receptacle  301 , with the piston  337  remaining secured to the fastener portion  317  of the receptacle.  
         [0146]     Thus, the piston  337  may slide relative to the body  330 , thereby generating suction in the storage chamber  338  that enables liquid contained in the receptacle to be sucked in via the orifice  323  of the receptacle and the passage  353  of the piston  337 .  
         [0147]     At the end of the stroke, the annular edge  333  of the body  330  may be pressed against the fastener portion  317  of the receptacle and the fastener portion  347  of the piston  337  so as to contribute to releasing the annular bead  348  from the groove  318  of the receptacle by elastic deformation.  
         [0148]     When the refillable unit  310  is removed from the receptacle, the spring  354  may return the ball  351  against the bearing surface  352  so as to close the orifice  355 , for example, as shown in  FIG. 7 .  
         [0149]     The user may dispense the liquid contained in the storage chamber  358  by actuating the pump  150 .  
         [0150]     The piston  337  may rise in the body  330  as the storage chamber  338  empties.  
         [0151]     Throughout the description, including in the claims, the term “comprising a” should be understood as being synonymous with “comprising at least one” unless specified to the contrary.  
         [0152]     Although the present invention herein is described with reference to particular exemplary embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention.