FR2752608A1 - Non=return valve for dispensing container - Google Patents

Abstract

The valve has a nozzle (37) with a base (40) which communicates with the dispenser. A nose (42) extends from the base and is provided with a free end. A longitudinal discharge channel (44) for the contents extends within the base and the nose. A finger (52) extends in the channel and is carried by the nozzle. A membrane covering the nose has an opening (59), which is coaxial to the finger and is elastically deformable between a position that closes the discharge channel, in which the edge of the opening is pressed against the finger, and a free position. The membrane is deformed through the action of the pressure differential between two opposite large surfaces of the membrane. The finger is integrally moulded with the nozzle.

Description

 The present invention relates to a non-return valve for product dispensing member and to a push-button for a product dispensing bottle equipped with such a valve.

 The invention also relates to a method of manufacturing this valve.

 There are known non-return valves of the type comprising a nozzle having a base intended to communicate with said dispensing member, a nose extending from the base and provided with a free end and a longitudinal product flow channel. extending in the base and the nose, a finger extending in said channel and carried by said tip and, capping said nose, a membrane provided with an orifice coaxial with said finger and elastically deformable between a closed position of the channel flow in which the edge of the orifice bears against the finger and a position for releasing said channel, under the action of differential pressure between the large mutually opposite surfaces of the membrane.

 The object of the invention is to produce a non-return valve having a relatively small number of parts and which can thus be manufactured at low cost in a production line at high speed.

 It therefore relates to a check valve of the aforementioned type, characterized in that said finger has come from molding with the end piece.

The invention may also include one or more of the following characteristics:
- The finger is connected to the tip by at least one longitudinal support rib extending in said product flow channel;
- Said nose has a convex external surface, and said membrane has a general shape complementary to that of the nose;
- the nose has a generally hemispherical external surface;
- Said tip has an external annular groove formed at the base of the nose in which engages a complementary surface of said membrane;
- Said finger projects beyond the nose and comprises at its free end a stud delimiting a seat for said membrane;
- Said membrane is overmolded on said tip;
- Said membrane is made of an elastomer and said tip is made of polypropylene.

 The subject of the invention is also a pusher cap for a fluid dispensing container intended to be mounted on a pumping member fitted to an open end forming the neck of said container and delimiting a chamber intended to be placed in communication with the pumping member and a product dispensing orifice, characterized in that said product dispensing orifice comprises a non-return valve according to as defined above.

Another object of the invention is to provide a method of manufacturing in one piece a non-return valve for a product distribution member, characterized in that it consists of:
- Molding, by injection of a plastic material, a nozzle comprising a body delimiting a longitudinal product flow channel and provided with a convex external surface and a finger extending in said channel and connected to the body by at least one support rib, said finger projecting beyond an end zone of the body and,
- Overmolding on said endpiece, by injection of an elastically deformable material, in particular an elastomer, a membrane covering said end region of the body and provided with an orifice the edge of which bears on said finger.

 Advantageously, during the molding of the body, an annular groove is made in the surface of the end region of the body using a punch.

Other characteristics and advantages will emerge from the following description, given only by way of examples and made with reference to the appended drawings in which
- Figure 1 is a general view partially in longitudinal section of a fluid dispenser container equipped with a push-button cap provided with a non-return valve according to the invention;
- Figure 2 is a longitudinal sectional view of a non-return valve according to the invention; and
- Figure 3 is a sectional view along the line
III-III of figure 2.

 In FIG. 1, a product dispensing container, designated by the general reference 10, has been represented. It has a plane of symmetry assumed to be vertical, situated in the plane of this FIG. 1.

 The bottle 10 is constituted by a hollow body 12 intended to receive a fluid product, such as a pharmaceutical or cosmetic product; a product pumping member 14 provided with a push-cap 16; and a cover 18 covering the pumping member 14 and the pusher cap 16.

 The hollow body 12 is made of a flexible material for the storage of the product away from air.

 I1 has a lower or proximal end 20 used for filling the body and closed by pinching and welding after filling, and an upper or distal end 22 which delimits a neck 24 opening out through a neck on which the sealing member is mounted pumping 14.

 The pumping member 14 comprises a support 26 for fixing to the neck 24 of the bottle 10, an elastically deformable membrane 28 covering the support 26 and on which the push-button cap 16 comes to bear.

 The push-button cap 16 delimits with the elastically deformable membrane 28 a chamber 30 for metering product of variable volume and is provided with a product dispensing orifice equipped with a non-return valve 32 for dispensing.

 I1 is mounted axially movable relative to the body 12 between a relaxed position for complete admission of product into the chamber 30, shown in FIG. 1, and a depressed position for complete discharge of product through the non-return distribution valve. 32, the membrane 28 urging the push-button cap 16 in the released position.

 Furthermore, the support 26 comprises a central stud 33 molded, mounted in the neck 24 and coaxial therewith.

 The stud 33 projects by one of its ends beyond the open end surface of the neck 24.

 The projecting end of the stud 33 has a frustoconical shape and delimits a bearing surface for the peripheral edge of an orifice 34 formed in the elastically deformable membrane 28.

 Furthermore, the support 26 comprises a tubular end piece 35 for centering the stud 33 on the neck 24.

The end piece 35 extends coaxially with the stud 33 and delimits therewith a set of channels, such as 36 for the product flow, these channels 36 being closed by the membrane 28 during the distribution of product to through the non-return valve.

 It will be appreciated that the assembly constituted by the elastically deformable membrane 28, the stud 33 and the product flow channels 36 constitute a non-return valve for closing the neck 24.

 Furthermore, the non-return valve 32 for dispensing product is produced in one piece by a plastic injection technique.

 Referring to Figures 2 and 3, the distribution check valve 32 comprises a nozzle 37 provided with a body 38 of circular section and of stepped external surface. It has an upstream end 40, considering the direction of flow of product, force fitted into a complementary orifice (not shown), formed in the wall constituting the push-button cap 16 and an opposite downstream end 42 free.

 The body 38 defines a longitudinal product flow channel 44 extending between the upstream 40 and downstream 42 ends.

 As mentioned above, the body 38 has an external surface of stepped shape. I1 comprises a base 46 extending from the upstream end 40 and of constant diameter greater than that of the orifice formed in the wall of the push-cap 16 in which it engages, a nose 48 located in the extension from the base 46 towards the free end 42 and having an outer surface of generally hemispherical shape, of sections smaller than that of the base 46, and an intermediate part situated at the base of the nose 48 and constituted by an annular groove 50 of section smaller than that of the base 46 and the nose 48.

 In addition, the end piece 37 has a central finger 52 extending in the product flow channel 44 coaxially therewith and connected to the body 38 by a support rib 54 preferably extending over the whole length of channel 44.

 It can be seen in FIG. 2 that the finger 52 extends, downstream, beyond the downstream end 42 of the body 38 and comprises at its free end a stud 56.

 Furthermore, the non-return valve 32 comprises an elastically deformable membrane 58 of generally substantially hemispherical shape covering the nose 48 and the annular groove 50 of the body 38.

 The membrane 58 has a regularly decreasing thickness downstream and has an orifice 59 whose edge is supported on a seat delimited by the stud 56.

 It can also be seen in FIG. 2 that the membrane 58 has at its upstream end an annular bead 60 engaging in the annular groove 50 of the body 38.

 Preferably, the end piece 37 and the membrane 58 are made from incompatible materials, that is to say non-missiles and having no compatible chemical bond, for example made of suitable elastomer and polypropylene respectively.

 The non-return valve 32 which has just been described operates in the following manner. When a user exerts a force on the push-button cap 16, the latter then moves axially relative to the support 26 from the relaxed position to the depressed position.

 This movement, which is exerted against the restoring force exerted by the elastically deformable membrane 28 on the push-button cap 16, is accompanied by a reduction in the volume of the metering chamber 30.

 The increase in the resulting pressure in the chamber 30 causes the closure valve for closing the neck 24 to close, by pressing the membrane 28 against the stud 33.

 Likewise, under the effect of the differential pressure prevailing between the two opposite surfaces of the diaphragm 58 of the non-return distribution valve 32, the latter deforms between a closed position of the product flow channel 44, shown in FIGS. 1 and 2, and a position for releasing this passage 44 by deformation of the thinned zone of the membrane located in the vicinity of the orifice 59.

 Thus, when a user exerts a force on the push-button cap 16 to maneuver it from the released position to the depressed position, the pumping member 14 is placed in the closed position and the pressure prevailing inside the chamber 30 the dosage increases, which causes the membrane 58 to pass from the closed position of the channel 44 to the release position of this channel, thus allowing the distribution of the product contained in the chamber 30.

 Furthermore, at the end of travel of the push-button cap, that is to say in the position of complete dispensing of the product contained in the chamber 30, when the user releases the push-button cap, the pumping member 14 causes it to rise. ci and thus a decrease in the pressure prevailing in the chamber 30, which causes the membrane 58 to pass from the release position of the channel 44 to the shutter position of the latter.

 It should be noted that during this movement, the pumping member 14 is placed in the open position for the admission of the product into the chamber 30.

 As previously mentioned, the non-return valve 32 which has just been described is produced in one piece in a production line at high speed.

 To manufacture such a valve, is molded by injection of a plastic material, in particular by injecting polypropylene into a suitable mold, the end piece 36, and in particular the body 38 delimiting the channel 44 and the finger 52 connected to the body 38 by rib 54.

 During this molding, the groove 50 described above is produced using an appropriate punch.

 In the same injection machine, the membrane 58 is produced, by molding, by injection, on the end piece 36 of an elastically deformable material, in particular of the elastomer, using an appropriate mold, providing orifice 59, the edge of which bears against the stud 56.

 It should be noted that, as mentioned previously, the constituent materials of the membrane and of the end piece 36 are incompatible so that no chemical bond is created between the membrane and the finger 52 in order to avoid any sticking between these elements, and in particular in order to avoid sticking between the membrane and the stud 56.

 A unitary assembly is thus obtained consisting of two elements forming a single piece which can then be mounted on a push-cap of a container equipped with a pump.

 The non-return valve which has just been described being produced in a single piece, by injection techniques which are easily implemented, it will be appreciated that its manufacture is of relatively low cost.

Claims (11)

 1. Non-return valve for product dispensing member, comprising a nozzle (37) comprising a base (40), intended to communicate with said dispensing member, a nose (42) extending from the base and provided of a free end, and a longitudinal product flow channel (44) extending in the base (40) and the nose (42), a finger (52) extending in said channel (44) and carried by said end piece (37) and, covering said nose (42), a membrane (58) provided with an orifice (59) coaxial with said finger (52) and elastically deformable between a position for closing the flow channel (44 ) in which the edge of the orifice (59) is in abutment against the finger (52) and a position for releasing said channel (44), under the action of the differential pressure between the two large mutually opposite surfaces of the membrane (58), characterized in that said finger (52) came from molding with the end piece (37).  2. A valve according to claim 1, characterized in that said finger (52) is connected to said end piece (36) by at least one longitudinal support rib (54) extending in said product flow channel (44).  3. Valve according to one of claims 1 and 2, characterized in that said nose (42) has a convex external surface and said membrane (58) has a general shape complementary to that of the nose (42).  4. Valve according to claim 3, characterized in that said nose (42) has an external surface of generally hemispherical shape.  5. Valve according to any one of claims 1 to 4, characterized in that said end piece (37) comprises an annular groove (50) formed at the base of the nose (42) in which engages a complementary surface (60) of said membrane (58).  6. Valve according to any one of claims 1 to 5, characterized in that said finger (52) protrudes beyond the free end of the nose and comprises at its free end a stud (56) delimiting a seat for said membrane.  7. A valve according to any one of claims 1 to 6, characterized in that said membrane (58) is overmolded on said tip (37).  8. Valve according to any one of claims 1 to 7, characterized in that said membrane (58) is made of an elastomer and said end piece is made of polypropylene.  9. Push-button cap (16) for a fluid dispenser container intended to be mounted on a pumping member (14) fitted to an open end forming the neck of said container, and delimiting a chamber (30) intended to be placed in communication with the pumping member (14) and a product dispensing orifice, characterized in that said product dispensing orifice comprises a non-return valve (32) according to any one of claims 1 to 6.  10. A method of manufacturing a single piece of a non-return valve (32) for a product distribution member (16), characterized in that it consists of  - Molding, by injection of a plastic material, a nozzle comprising a body (38) delimiting a longitudinal product flow channel (44) and provided with a convex external surface and a finger (52) extending in said channel and connected to the body by at least one support rib (54), said finger projecting beyond an end zone of the body (38) and,  - overmolding, on said endpiece (36), by injection of an elastically deformable material, in particular an elastomer, a membrane covering said end region of the body and provided with an orifice the edge of which is in abutment on said finger (52 ).  11. The manufacturing method according to claim 10, characterized in that during the molding of the body (38), an annular groove (50) is produced in the external surface of the body (38) using a punch. ) in said end region of the body.