Patent Publication Number: US-7717302-B2

Title: Pump and a receptacle fitted therewith

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims the benefit of U.S. Provisional Application No. 60/438,324 filed on Jan. 7, 2003, the disclosure of which is incorporated by reference herein. 

   BACKGROUND OF THE INVENTION 
   1. Field of Invention 
   The present invention relates in particular to a pump for mounting on a receptacle, and serving to dispense a substance in a head-up or a head-down position. 
   2. Description of Related Art 
   French Patent Application No. FR 2 528 122 discloses a pump enabling a substance to be dispensed in a head-up or a head-down position, and comprising a pump body with a moving assembly in the pump body and co-operating therewith to define a pump chamber of variable volume. 
   The pump body has a lateral opening enabling the substance contained in the receptacle to penetrate into the pump chamber when the pump is used head-down. The moving assembly has a lip enabling the above-mentioned opening in the pump chamber to be isolated after it has been moved a certain distance into the pump body. 
   Such a pump has two helical springs which are in contact with the substance, and that can lead to problems of compatibility between the substance and the metal of the springs. 
   In addition, that pump has a relatively large number of parts, which is reflected in its manufacturing cost. 
   Finally, if the pump is held head-down for a long period, it can happen that the substance will leak out, particularly if the substance is not very viscous. 
   SUMMARY OF THE INVENTION 
   There exists a need for a pump which remedies those drawbacks in full or in part, and in particular which is relatively simple in structure while enabling a substance to be dispensed in satisfactory manner, even when the substance is not very viscous. 
   In an exemplary embodiment, the invention provides a pump for mounting on a receptacle, the pump comprising: 
   a pump body; and 
   a moving assembly that is movable relative to the pump body and that co-operates therewith to define a pump chamber of variable volume, the pump chamber being suitable for communicating with the inside of the receptacle via at least one opening of the pump body disposed in such a manner as to enable the pump to operate in a head-down position, the pump further comprises: 
   an air intake passage formed between the pump body and the moving assembly and capable of communicating with the opening of the pump body; 
   a first lip arranged, after the moving assembly has moved away from a rest position in the substance-dispensing direction, to press in leaktight manner against the pump body and prevent communication between the inside of the receptacle and the pump chamber via the opening; and 
   a second lip situated above the first lip when the pump is in the head-up position, wherein the second lip is arranged to close the air intake passage when the moving assembly is in its rest position, and to release the air intake passage when the moving assembly is displaced in the substance-dispensing direction. 
   In various exemplary embodiments, the invention is usable in particular to reduce the risk of substance leaking out in the event of the pump being held head-down at rest. 
   Since the moving assembly includes a dispenser orifice, the orifice can be situated, for example, on the side opposite from the opening if there is only one opening, thereby avoiding the pump chamber from emptying when the pump is used in a substantially horizontal position with the dispenser orifice facing downward. 
   Advantageously, each of the first and second lips presents a shape that is substantially frustoconical, flaring toward the pump chamber. 
   In an exemplary embodiment of the invention, the moving assembly includes a third lip disposed in such a manner as to be pressed against the pump body to close the air intake passage when the moving assembly is at the end of its substance-dispensing stroke, thus making it possible when the pump is used head-down to avoid substance leaking out even if the moving assembly is maintained for an extended period in its end-of-stroke position. 
   In an exemplary embodiment of the invention, the pump body and the second lip may be arranged in such as manner as to close the air intake passage when the moving assembly is at the end of its stroke, in which case the moving assembly need not have a third lip. In this exemplary embodiment, the pump body may include, for example, at least one setback, in particular a channel extending parallel to the axis along which the moving assembly moves, said setback being situated between two regions against which the second lip presses when the moving assembly repetitively occupies its rest position and its end-of-stroke position. The setback provides communication between the regions when the moving assembly occupies a position that is intermediate between its rest position and its end-of-stroke position. 
   In an exemplary embodiment of the invention, the moving assembly comprises a pushbutton and an insert fitted thereto, the pushbutton and the insert being arranged together to define a passage for delivering the substance, at least when the pump is actuated to dispense the substance. 
   The first, second, and third above-mentioned lips may be made on the insert. 
   In an exemplary embodiment of the invention, the pushbutton comprises two portions, one of which is stationary relative to the insert and the other is movable relative thereto, the insert and the movable portion of the pushbutton may include respective surfaces for co-operating to close the passage for delivering the substance when the moving assembly is in its rest position and for opening the passage when the movable portion is moved through a determined distance relative to the stationary portion. 
   In the exemplary embodiment described, the pushbutton is arranged so that the movable portion can move through the above-mentioned determined distance relative to the insert from its rest position only when the force exerted on the pushbutton exceeds a threshold. This enables the passage for delivering the substance to be disengaged only once the substance has been compressed in the pump chamber. 
   The stationary portion and the movable portion of the pushbutton may be connected to each other by a web of elastically-deformable material, the web possibly presenting an annular shape. 
   In an exemplary embodiment of the invention, the pump includes a resilient return element suitable for returning the moving assembly into its rest position. The resilient return element may be placed outside the pump chamber and comprise, for example, a helical spring working in compression. Advantageously, the resilient return element is made integrally with the pushbutton. 
   In an exemplary embodiment of the invention, the pump body is arranged to enable a dip tube to be fastened thereto, and the pump may include a check valve that closes while the volume of the pump chamber is decreasing and that opens while the volume of the pump chamber is increasing. This check valve can be disposed in such a manner to enable the pump chamber to be fed with substance via the dip tube when the pump is used head-up. 
   Advantageously, the volume of the pump chamber in the rest position is greater than the volume of a quantity or “dose” of substance to be dispensed, thereby reducing the risk of the pump becoming unprimed. 
   In an exemplary embodiment of the invention, the pushbutton is stationary relative to the insert with the insert possibly including a skirt suitable for co-operating in leaktight manner with a spike of the pump body while the pump is at rest in order to isolate the pump chamber from the outside. 
   The insert may include a check valve suitable for closing an upper opening of the skirt while the volume of the pump chamber is increasing and suitable for allowing substance to pass through while the volume of the pump chamber is decreasing. 
   The check valve may comprise a valve member that is connected to the skirt by a web of frangible material, prior to first use of the pump. The valve member may come into abutment against the spike when the pushbutton is depressed in order to rupture the web of frangible material. 
   Independently or in combination with the above, the invention also provides, in an exemplary embodiment, a pump for mounting on a receptacle, the pump comprising: 
   a pump body, the pump body including a spike; and 
   a moving assembly including a pushbutton and arranged to co-operate with the pump body to define a pump chamber of variable volume, the moving assembly including a skirt via which substance present in the chamber can be delivered toward a dispensing orifice, the skirt being capable of co-operating with the spike when the pump is at rest in order to isolate the inside of the skirt from the pump chamber. 
   By way of example, the skirt may be provided with a valve member which, prior to first use of the pump, is connected to the skirt by a web of frangible material. When the moving assembly is moved downwards on first use of the pump, the valve member comes into abutment against the spike and is moved inside the skirt until it reaches a position where the valve member co-operates with an upper opening of the skirt to form a check valve. In operation of the pump, the check valve opens while the volume of the pump chamber is decreasing and closes while the volume of the pump chamber is increasing, thereby preventing air from being sucked into the pump chamber and enabling it to become filled with substance. 
   The invention also provides a receptacle fitted with a pump as defined above. 
   In an exemplary embodiment, the invention also provides independently or in combination with the above, a pump for mounting on a receptacle, the pump comprising: 
   a pump body; and 
   a moving assembly that is movable relative to the pump body and that co-operates therewith to define a pump chamber of variable volume; 
   the pump having a moving assembly comprising a pushbutton and an insert fitted to the pushbutton, the pushbutton and the insert being arranged together to define a passage for delivering the substance when the pump is actuated to dispense the substance, and by the fact that the pushbutton comprises two portions, one of which is stationary relative to the insert and the other of which is movable relative thereto, the movable portion and the insert having respective surfaces suitable for co-operating to close the passage for delivering the substance when the moving assembly is in its rest position, and for disengaging the passage when the movable portion is moved through a determined distance relative to the stationary portion. 
   These and other features and advantages of the disclosed embodiments are described in, or are apparent from, the following detailed description of various exemplary embodiments according to this invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention can be better understood on reading the following detailed description of non-limiting exemplary embodiments thereof, and on examining the accompanying figures, in which: 
       FIGS. 1–3  illustrate a first exemplary embodiment of a pump mounted on a receptacle according to this invention; 
       FIG. 4  illustrates a second exemplary embodiment of a pump according to this invention; 
       FIGS. 5–7  are cross-sectional views illustrating stages in the operation of the second exemplary embodiment of a pump according to this invention; 
       FIG. 8  illustrates a third exemplary embodiment of a pump according to this invention; and 
       FIGS. 9–10  illustrate a first exemplary embodiment of a receptacle fitted with the pump according to this invention. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   The following detailed description of various exemplary embodiments of a pump and a receptacle fitted therewith may refer to and/or illustrate one specific application, a spray bottle, for the sake of clarity and familiarity. However, it should be appreciated that the principles of this invention as outlined and/or discussed below can be equally applied to any known, or later-developed, pump and receptacle system beyond the simple spray bottle specifically discussed herein. 
     FIGS. 1–9  show a pump  1  mounted on a neck  2  of axis X of a receptacle  3  containing a substance P to be dispensed. 
   The pump  1  comprises a stationary portion  4  and a moving assembly  5  capable of moving along the axis X. 
   The stationary portion  4  includes an assembly skirt  9  secured to the neck  2  of the receptacle  3 . In the exemplary embodiment described, the assembly skirt  9  is snap-fastened to the neck  2 , but it should be appreciated that, in other embodiments, the assembly skirt could be fastened other ways such as, for example, by screw fastening or by crimping the assembly skirt  9 . 
   The assembly skirt  9  is extended upwards by a cylindrical wall  10  having an inwardly-directed annular bead  11  at the top end of the cylindrical wall  10 . 
   The stationary portion  4  also includes a sealing lip  12  bearing against the inside surface of the neck  2 , and a pump body  14  co-operating with the moving assembly  5  to define a variable volume pump chamber  6 . When the pump is observed head-up, as shown in  FIG. 9 , the pump body  14  presents an upper tubular wall  15  and a lower tubular wall  16  that are coaxial about the axis X. 
   The lower wall  16  presents a circularly cylindrical inside surface  16   a  of diameter smaller than the diameter of the likewise circularly cylindrical inside surface  15   a  defined by an annular bead  17  present at the top end of the upper wall  15 . 
   The upper wall  15  is provided, at its base, with a plurality of side openings  18 , only one of which is visible in the drawing. These openings  18  are distributed generally circumferentially around the upper wall  15 . The pump body  14  need have only one of said openings. 
   The lower wall  16  is connected to an endpiece for fastening a dip tube  24  to the bottom end of the pump body  14 . The endpiece  20  also defines a housing for a ball  21 , which ball is held in its housing by bosses  22 . 
   The housing for the ball  21  communicates via an orifice  23  with the dip tube  24 . 
   The moving assembly  5  comprises a pushbutton  30  having an insert  31  fitted therein. 
   The pushbutton  30  comprises a first portion  32  which is stationary relative to the insert  31 . The first portion  32  includes an outer tubular skirt presenting an annular bead  33  at its bottom end suitable for co-operating with the annular bead  11  of the cylindrical wall  10  in order to retain the moving assembly  5  on the portion  4  of the pump that is fastened to the receptacle  3 . 
   The first portion  32  also includes a delivery orifice  34  communicating with a swirling channel chamber  35  formed in the insert  31  usable to enable the substance to be dispensed in the form of a spray. 
   The pushbutton  30  also includes a second portion  36  that is movable relative to the first portion  32 . In the exemplary embodiment described, the second portion  36  comprises a hollow rod that is open at its top end and closed at its bottom end. This rod is connected to the first portion  32  by a web of material  37  that is elastically deformable and annular in shape. 
   The insert  31  has a central duct  39  in which the second portion  36  of the pushbutton  30  is engaged while leaving a passage  38  for delivery of the substance when the pump is actuated to dispense the substance. 
   The insert  31  includes a first annular lip  40  arranged to press in leaktight manner against the inside surface  16   a  of the pump body  14  while the moving assembly  5  is being moved downward through a determined stroke from its rest position of  FIG. 1 , as shown in  FIG. 2 . 
   Above the first lip  40 , the insert  41  has a second annular lip  41  bearing in leaktight manner against the inside surface  15   a  while the moving assembly is in its rest position, as shown in  FIG. 1 . 
   The shape of this second lip  41  is selected in such a manner that when it leaves the annular bead  17  during displacement of the moving assembly  5  to reduce the volume of the pump chamber  6 , the lip  41  ceases to bear in leaktight manner against the upper wall  15  and co-operates therewith to leave an air intake passage  42  enabling the inside of the receptacle  3  to communicate with the outside through the plurality of openings  18 , as shown in  FIG. 2 . 
   In the exemplary embodiment described, each of the lips  40  and  41  is frustoconical in shape, flaring toward the pump chamber  6 . 
   A third annular lip  45  is made on the insert  31  above the second lip  41  usable to bear in leaktight manner against the inside surface  15   a  when the moving assembly  5  is in its end-of-dispensing-stroke position, as shown in  FIG. 3 , closing the air intake passage  42 . 
   The second portion  36  of the pushbutton  30  includes an annular lip  46  suitable for bearing in leaktight manner against the insert  31  to close the passage  38  for delivering substance while the moving assembly  5  is in its rest position. 
   A setback such as an annular groove is made in the insert  31 . The lip  46  occupies a position facing this setback while the second portion  36  is moving downward through a certain distance relative to the insert  31 , as shown in  FIG. 2 , thus allowing substance to pass from the pump chamber toward the outlet orifice  34 . 
   The pushbutton  30  includes a helical spring  49  working in compression. In the exemplary embodiment described, the helical spring  49  is made integrally with the first portion  32 , extending it downwards. The helical spring  49  is housed between the outer wall  10  and the inner wall  15  of the stationary portion  4 . 
   An exemplary pump  1  according to this invention operates substantially as follows. 
   It is assumed initially that the pump  1  is being used head-up, and that it is initially in its rest position as shown in  FIG. 1 . It is assumed that the pump chamber  6  is full of substance following an earlier actuation cycle of the pump. 
   The inside of the receptacle is isolated from the outside by leaktight contact between the second lip  41  and the inside surface  15   a , and by leaktight contact of the lip  46  of the pushbutton on the surface  31   a  of the insert  31  situated above the setback  47 . 
   In order to dispense the substance, the user exerts downward pressure on the central, second portion  36  of the pushbutton  30 . 
   Given that the rest shape of the web of material  37  is slightly outwardly convex, a certain amount of force is required to cause this web of material  37  to change configuration and deform, taking up a substantially upwardly concave configuration, as shown in  FIG. 2 . 
   In this way, the moving assembly  5  begins by moving relative to the stationary portion  4  of the exemplary pump  1  without the displacement of the second portion  36  relative to the first portion  32  being sufficient for the lip  46  to cease bearing in leaktight manner against the surface  31   a  of the insert  31 . 
   In particular, in the exemplary embodiment described, the passage  38  for delivering substance remains closed by the lip  46  at least until the first lip  40  comes to bear in leaktight manner against the surface  16   a  of the pump body  14 . 
   The pressure of the substance contained in the pump chamber  6  increases as the moving assembly continues to move, the ball  21  being pressed against its seat. 
   The force needed to move the moving assembly  5  relative to the stationary portion  4  increases as the substance is compressed in the pump chamber  6 , and at some moment the force exerted on the pushbutton  30  becomes sufficient for the web of material  37  to deform to such an extent as to allow the lip  46  to reach the setback  47 . 
   When a flow of substance can be established via the passage  38  between the pump chamber  6  and the outlet orifice  34 , the substance is already compressed in the pump chamber  6 , so the chamber  35  is fed with sufficient pressure to form a spray. Such an exemplary pump is termed a “precompression” pump. 
   Continued displacement of the moving assembly  5  relative to the stationary portion  4  of the pump  1  causes the volume of the pump chamber  6  to be decreased. 
   During downward displacement of the moving assembly  5 , the second lip  41  ceases to press in leaktight manner against the surface  15   a , such that the inside of the receptacle can communicate with the outside through the plurality of openings  18  and the passage  42 , allowing air to be taken in, where appropriate. 
   At the end of the depression stroke of the moving assembly  5  relative to the stationary portion  4 , the third lip  45  comes to bear against the surface  15   a , thereby closing communication between the inside of the receptacle and the outside via the passage  42 . During the displacement of the moving assembly  5 , the helical spring  49  is compressed. 
   When the user ceases to press on the pushbutton  30 , the web of material  37  tends to return to its initial configuration and the second portion  36  tends to move upward relative to the first portion  32 , thereby reestablishing leaktight contact between the lip  46  and the insert  31 , and closing the passage  38  that put the inside of the pump chamber  6  into communication with the delivery orifice  34 . 
   Continued upward movement of the moving assembly  5  relative to the stationary portion  4  is accompanied by substance being sucked into the pump chamber  6  under the effect of the suction that is created therein, the first lip  40  pressing on the surface  16   a . Air intake can occur via the passage  42  in order to compensate inside the receptacle for the volume of substance drawn in by the pump  1 . While air is being taken in, the air that is sucked into the receptacle can oppose delivery of the substance via the passage  42  given the narrowness of the passage. Once the pump  1  returns to its rest position, the substance can remain inside the pump chamber  6  because the ball  21  tends, under the effect of its own weight, to be pressed against its seat and to close the orifice  23 . 
   When the pump is used head-down, the pump chamber  6  can fill by the plurality of openings  18 . Substance is dispensed in the same manner as in the head-up position. The same applies when the pump  1  is used in an intermediate position between its head-up and head-down positions, with the delivery orifice  34  pointing downward, providing the receptacle contains sufficient substance. 
   When the pump is used head-down, the fact that firstly the second lip  41  presses in leaktight manner against the surface  15   a  while the pump  1  is at rest and secondly that the lip  46  presses against the insert  31  in leaktight manner enables risk of substance leakage to be avoided. 
   The risk of substance leakage is also reduced, if the pump  1  is held head-down with the moving assembly  5  in its end-of-stroke position, because of the third lip  45  pressing against the surface  15   a.    
   In the exemplary embodiment described, the pump chamber  6  presents a volume that is greater than the quantity or “dose” of substance that is dispensed, thereby making it possible to reduce the risk of the pump ceasing to be primed. 
     FIGS. 4–7  illustrate a pump  60  comprising a stationary portion  61  and a moving assembly  62  capable of moving along the axis X. 
   The stationary portion  61  is similar to the above-described stationary portion  4  with the exception that in this example the ball  21  is retained in its housing by bosses  63  made on tabs  64  extending from the bottom of the pump body  65 , and the plurality of openings  18  are replaced by a single opening  88  situated on the side opposite from the delivery orifice  70 . 
   The moving assembly  62  comprises a pushbutton  67  having an insert  68  fitted thereto. 
   The pushbutton  67  comprises a first portion  69  which is stationary relative to the insert  68  and which includes the delivery orifice  70 , which orifice is similar to the above-described delivery orifice  34 . 
   The pushbutton  67  further comprises a spike  71  which is movable axially relative to the first portion  69  and which is connected thereto by a web of material  72 , like the second portion  36  of the pump  1 . 
   The insert  68  includes a central duct  74  whose bottom end  75  penetrates into the space defined between the tabs  64 . 
   The spike  71  is engaged in the top portion of the duct  74  and includes an annular bead  76  bearing in leaktight manner in the rest position against an annular region  74   a  of the wall of the duct  74  (shown in  FIG. 4 ), thereby interrupting communication between the substance delivery passage  77  and the pump chamber. 
   The central duct  74  includes a portion of enlarged section  78  beneath the region  74   a , which portion is arranged so that when the spike  71  is pushed into the duct  74  over a certain stroke, the annular bead  76  ceases to bear against the region  74   a , thereby enabling substance to be delivered via the passage  77 . 
   In the exemplary embodiment described, the fact that the opening  88  is situated on the side opposite to the delivery orifice  70 , avoids the pump chamber emptying in the event of the pump being used substantially horizontal with the delivery orifice  70  pointing downward. 
   Unlike the insert  31  of the first exemplary embodiment above, the insert  68  has only two annular lips  80  and  81 , analogous respectively to the annular lips  40  and  41  in  FIG. 1 . The insert  68  does not have a third annular lip. 
   The upper wall  82  of the pump body  65  comprises two annular regions  83  and  84  that are circularly symmetrical and that have at least one channel  85  extending along the axis X formed between them. 
   The second annular lip  81  can be pressed in leaktight manner against these regions  84  and  83 , respectively, when the moving assembly  62  is occupying its rest position and its end-of-stroke position, as shown in  FIGS. 5 and 6 . The channel  85  can allow air to be taken in when the moving assembly  62  is occupying an intermediate position, as shown in  FIG. 7 . 
   Like pump  1 , pump  60  is a precompression pump. 
   In order to dispense substance, the user exerts downward pressure on the pushbutton  67 . 
   The moving assembly  62  begins by moving relative to the stationary portion  61  without the spike  71  moving relative to the first portion  69  sufficiently for the annular bead  76  to cease pressing in leaktight manner against the region  74   a  of the duct  74 . 
   The passage  77  for delivering the substance thus remains isolated from the pump chamber by the bead  76 , at least until the first lip  84  comes to bear in leaktight manner against the pump body  65 , as shown in  FIG. 5 . 
   As described with reference to the pump  1 , at a certain moment, the force exerted on the pushbutton  67  becomes sufficient for the web of material  72  to deform to a certain extent as to allow the annular bead  76  to go past the enlarged section  78 , thereby allowing the substance to reach the passage  77 . 
   During downward displacement of the moving assembly  62 , as shown in  FIG. 7 , the second annular lip  81  ceases to press against the pump body  65 , thereby making it possible for air to be taken in via the channel  85 , should that be necessary. 
   At the end of the stroke of the moving assembly  62 , the second annular lip  81  comes to press in leaktight manner against the region  83 , as shown in  FIG. 6 , thereby preventing communication between the inside of the receptacle and the outside. 
   When the user ceases to press on the pushbutton  67 , the web of material  72  tends to return to its initial configuration under the action of the spring  49 ′. The spike  71  moves upwards relative to the first portion  69  of the pushbutton  67  in such a manner that the annular bead  76  again presses against the region  74   a  of the duct  74 . The passage  77  for delivering the substance is thus closed. 
   Continued upward movement of the moving assembly  62  relative to the stationary portion  61  causes substance to be sucked into the pump chamber, the first lip  80  pressing against the pump body  65  above the opening  88 , as shown in  FIG. 5 . 
   Air may be taken in through the opening  88  while the second lip  81  is in an intermediate position between the regions  83  and  84 , as shown in  FIG. 7 . 
   When the pump  60  is used head-down, the pump chamber can fill via the opening  88 . 
   It is not essential in the exemplary embodiments according to this invention for the pushbutton  67  to have first and second portions that are movable relative to each other as is the case in the example described above. 
     FIG. 8  illustrates a pump  90  comprising a moving assembly  91  capable of moving relative to a stationary portion  92 . 
   The moving assembly  91  comprises a pushbutton  93  having an insert  94  fitted therein. The insert has two annular lips  119  and  122  similar respectively to the above-described lips  80  and  81 . 
   The pushbutton  93  is stationary relative to the insert  94 . 
   The insert  94  has a recess  95  extending substantially along the axis X and co-operating with a tubular central portion  96  of the pushbutton  93  to define a portion of the passage  97  for delivering the substance. 
   At its first portion, the insert  94  presents a cylindrical skirt  99  that is circularly symmetrical about the axis X and that is suitable for engaging on a central spike  100  of the pump body  101 . 
   At its bottom end, the inside of the skirt  99  presents an annular bead  102 , and at its top end it presents an opening  115  defined by a downwardly flaring frustoconical portion  116 . 
   Prior to first use of the pump  90 , the skirt  99  houses a valve member  105  disposed above the annular bead  102  and including at its top end a head  120  which can initially be secured to the skirt  99 . The head  120  has a frustoconical annular surface  120   a.    
   The skirt  99  and the valve member  105  may be made as a single piece by molding. The valve member  105  may be connected to the skirt  99  by a web of frangible material making it possible, after rupturing, to allow the valve member  105  to move relative to the skirt  99 . The valve member  105  may also comprise an element made separately and then installed in the skirt  99  after the skirt has been manufactured. 
   The valve member  105  has a bottom conical recess  106  suitable for engaging on the conically-shaped top end  107  of the spike  100  when the moving assembly  91  has been depressed over a certain stroke. 
   At the base of the conical portion  107 , the spike  100  has an annular bead  108 . When the moving assembly  91  is in its rest position, the bead  108  bears against the annular bead  102  of the skirt  92  to prevent substance from penetrating into the skirt  99 . 
   The spike  100  is connected to the remainder of the pump body  101  by bridges of material  110 , e.g. being integrally molded with the remainder of the pump body. 
   Prior to first use of the pump  90 , the user pushes in the moving assembly  91 . After it has moved through a certain stroke relative to the stationary portion  92 , the valve member  105  comes into abutment against the conical portion  107  of the spike  100 . As the user continues to exert force on the moving assembly  91 , the valve member  105  goes through the frustoconical portion  116  of the skirt  99  to take up the position shown in chain-dotted lines in  FIG. 8 , in which position the valve member  105  co-operates with the opening  115  to form a check valve. 
   The exemplary pump  90  operates substantially as follows. 
   It is assumed initially that the pump  90  is being used head-up, and is initially in its rest position as shown in  FIG. 8 . 
   It is assumed that the pump chamber is full of substance following an earlier actuation cycle of the pump. 
   The pump chamber is isolated from the outside by leaktight contact of the second lip  122  on the pump body  101  and by leaktight contact also of the annular bead  108  of the spike  100  on the annular bead  102  of the skirt  99 . 
   To dispense the substance, the user exerts downward pressure on the moving assembly  91 . 
   The exemplary pump  90  may be a precompression pump like the exemplary pumps  1  and  60 , providing the height of the annular bead  102  is selected so that the beads  102  and  108  press against each other over a certain stroke of the moving assembly  91  relative to the stationary portion  92 , at least until the annular lip  119  comes to press against the pump body  101  beneath the opening  88 . 
   After a certain stroke has been traveled, the annular beads  102  and  108  cease to press against each other, thereby enabling the substance contained in the pump chamber to flow in the skirt  99  toward the delivery passage  97 , with the pressure of the substance being suitable for lifting the valve member  105  so that the surface  120   a  of the head  120  ceases to press against the edge of the opening  115 . 
   While the moving assembly  91  is moving inward relative to the stationary portion  92 , the first and second annular lips  119  and  122  co-operate with the pump body  101  in a manner analogous to that described above for the annular lips  80  and  81 . 
   When the user ceases the press on the pushbutton  93 , the moving assembly  91  tends to return to its initial position under drive from the spring  49 ′. 
   The head  120  of the valve member  105  then returns to press against the edge of the opening  115  of the skirt  99  to isolate the pump chamber from the outside and to enable substance to be sucked into pump chamber under the effect of the suction which is created therein, the first lip  119  being pressed against the pump body  101  beneath the opening  88 . 
   The invention is naturally not limited to the embodiments described above. 
   The ball  21  may be replaced in particular by any other suitable check valve, in particular an elastomer check valve fitted to, or overmolded on, the pump body. 
   It would not go beyond the ambit of the present invention for the pump to operate without precompression, using a moving assembly configured differently. 
   Throughout the description, including in the claims, the term “comprising a” should be considered as synonymous with “comprising at least one” unless specified to the contrary. 
   Although the present invention herein has been described with reference to particular 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 exemplary embodiments. Other arrangements, alternatives, modifications, variations and/or improvements may be devised without departing from the spirit and scope of the present invention. Therefore, the structures and/or devices according to this invention are intended to embrace all known, or later developed alternatives, modifications, variations, and/or improvements.