Piston container

Abstract

Piston container. Container (10) comprising: A body (20), A rotating cap (40), An insert (50) comprising a threaded hollow rod (51), A piston (30) movable axially along the hollow rod between an initial position where it is in contact with the head (54) and a final position where it is near the proximal end of the threaded hollow rod, A first sealing gasket (60) interposed between the peripheral ring and the cylindrical surface (22), the friction of the piston (30) on the tubular portion (21) being sufficient to prevent the piston from rotating relative to the tubular portion while allowing it to move axially on the rod (51) during the rotation of the cap (40), A second sealing gasket (70) interposed between the piston (30) and the head (54) of the insert (50) when the piston is in its initial position. Figure for the abbreviation: Fig. 2

Description

Title of the invention: Piston container technical field

[0001] The present invention relates to a piston container, and more particularly but not exclusively to a container usable as a replaceable cartridge within a cosmetic composition dispenser. Previous technique

[0002] EP 4 086 189 Al discloses a cosmetic composition dispenser configured to receive several cartridges containing different cosmetic compositions, in order to allow the delivery of a personalized formulation from these compositions.

[0003] Each cartridge contains:

[0004] a body having a tubular part elongated along a longitudinal axis, open at its distal end, the tubular part having a cylindrical internal surface of revolution,

[0005] a cap mounted on the body on the side of its distal end, so as to be able to rotate relative to the body,

[0006] a central insert comprising a hollow rod having an external thread, the hollow rod being open at its proximal end, the central insert rotating with the cap, the hollow rod being extended on the distal side by a head fixed in the cap,

[0007] a piston mounted on the threaded rod, comprising an internally threaded hub engaged on the external thread of the hollow rod, and a peripheral ring in contact with the cylindrical inner surface of the tubular part, the piston being axially mobile along the hollow rod between an initial position where it is in contact with the head and a final position where it is close to the proximal end of the hollow rod, the friction of the piston on the body being sufficient to immobilize the piston in rotation relative to the body while allowing it to move axially on the threaded hollow rod during the relative rotation of the body and the cap under the action of the distributor.

[0008] The compartment defined inside the body between the piston and the proximal end of the body contains the composition to be dispensed. During rotation of the cap relative to the body, the piston moves towards the proximal end of the body and decreases the volume of this compartment, the composition being expelled through the hollow threaded rod.

[0009] Concurrently, the compartment located inside the body between the piston and the cap increases in volume during the piston's movement. Air is drawn in through a gap in the cap's mounting on the body.

[0010] The development of such a cartridge requires finding a compromise between several conflicting requirements.

[0011] On the one hand, the piston must apply itself with sufficient friction to the cylindrical surface of revolution of the cartridge body so as not to rotate relative to it during the relative rotation of the body and the cap.

[0012] On the other hand, the piston must not apply too strongly to the body, otherwise it risks generating too great a force between the cooperating threads of the hollow rod and the hub, leading to their damage.

[0013] Finally, the piston must be able to move on the threaded rod without slipping off it and providing the required seal.

[0014] Another example of a cartridge is described in application FR 3 042 293.

[0015] Application FR 3 029 088 describes another example of a distributor.

[0016] Applications FR 2 983 046 and FR 2 864 431 describe applicators comprising a piston mounted on a hollow threaded rod, the piston being made with a peripheral sealing lip formed from the material with the hub engaged on the threaded rod. In application FR 2 983 046, the piston may include a sealing ring engaged on the threaded portion of the rod.

[0017] US application 2013 / 0299515 Al discloses a two-piston container having sealing lips at its periphery. Description of the invention

[0018] The cartridge disclosed in application EP 4 086 189 Al offers satisfaction for the packaging and distribution of fairly viscous compositions exhibiting relatively low sensitivity to oxidation.

[0019] However, for compositions sensitive to oxidation, the shelf life may prove insufficient in some cases.

[0020] There is therefore a need to further improve containers of the type described in application EP 4 086 189 A1, in order to improve the storage conditions of the composition. Summary of the invention

[0021] The invention aims to meet this need, and it achieves this by proposing a container comprising: - A body having an elongated tubular portion along a longitudinal axis, intended to contain a fluid composition, open at its distal end, the tubular portion having a cylindrical internal surface of revolution, - A cap mounted on the tubular body at its distal end, so as to be able to rotate relative to the tubular part, - A central insert comprising a hollow stem having an external thread, the hollow stem being open at its proximal end, the central insert rotating with the cap, the hollow stem being extended on the distal side by a head fixed in the cap, - A piston mounted on the threaded rod, comprising an internally threaded hub engaged on an external thread of the hollow rod, and a peripheral ring opposite the cylindrical inner surface of the body, the piston being axially mobile along the hollow rod between an initial position where it is in contact with the head and a final position where it is close to the proximal end of the threaded hollow rod, - A first sealing gasket, made of elastomer, carried by the peripheral ring, interposed between the peripheral ring and the cylindrical surface, the friction of the piston on the tubular part being sufficient to immobilize the piston in rotation relative to the tubular part while allowing it to move axially on the hollow threaded rod during the relative rotation of the body and the cap, - A second sealing gasket, made of elastomer, interposed between the piston and the insert head when the piston is in its initial position.

[0022] Thanks to the invention, the airtightness of the compartment containing the composition, until its first use, is improved without impairing the proper functioning of the mechanism that causes the piston to move during the relative rotation of the cap and the body. The cap can rotate relative to the cylindrical body held fixed by the distributor; the piston can move axially along the body and along the screw, the screw rotating within the piston.

[0023] The invention thus makes it possible to maintain sufficient friction force between the piston and the cylindrical surface of revolution of the body to guarantee the rotational translation drive of the piston along the hollow threaded rod, without generating excessive friction opposing the axial advance of the piston and a risk of damage to the cooperating threads of the piston and the threaded rod.

[0024] The body and piston can be made by injection molding of a thermoplastic material. The piston can be made of a material having a Shore D hardness greater than or equal to 80 according to ISO 48-4. The piston can be made of a material having an elongation before break of less than 5%, preferably 3% according to ISO 527-1 / -2. The piston can, in particular, be made of a non-polyolefin material, preferably PBT (polybutene terephthalate). The piston can also be made of metal, ceramic, or other materials.

[0025] Preferably, the threaded area of ​​the piston extends over more than 50% of the total axial dimension of the piston; an extended threaded area helps to limit the risk of piston binding and also creates a greater pressure drop, and therefore a better seal at the screw / piston interface. The length of the threaded area of ​​the piston is, for example, more than 75% of the internal diameter of the piston thread. For example, a threaded area length of more than 4 mm, for example, between 4 and 6 mm, for an internal diameter of the threaded area between 5 and 6 mm.

[0026] The piston and the insert can both be made of a non-polyolefin thermoplastic material. In particular, they can be made of a relatively hard material, with a tight gap, which allows for a good seal between the piston and the threaded rod during use of the container.

[0027] The first sealing gasket may be made of a fluoroelastomer. The nature of the gasket and its flexibility can be adjusted according to the composition and friction (a composition containing grease or oil facilitates rotational and translational movements and reduces friction between the body and the piston).

[0028] The first sealing element is preferably an O-ring. One type of O-ring offers a good compromise between sealing performance and the friction generated by its application to the cylindrical surface of the container body. The seal may also have a different shape, such as lobes, a lip, or another type.

[0029] The second sealing ring is preferably also an O-ring. The use of an O-ring helps to limit the force required during the initial drive of the piston to move it away from the insert head.

[0030] The second sealing gasket is preferably carried by the head of the insert.

[0031] The piston may include a sealing lip extending from the hub on the distal side, this lip applying to the second sealing seal when the piston is in its initial position.

[0032] The peripheral crown of the piston may have on the proximal side of the crown a first annular lip opposite the cylindrical surface of revolution of the body.

[0033] This first lip may have a chamfer on the proximal side.

[0034] The peripheral crown of the piston may have on the distal side of the crown a second annular lip opposite the cylindrical surface of revolution of the body.

[0035] This second lip may have a chamfer on the distal side.

[0036] The second lip may include an annular groove receiving the first sealing gasket.

[0037] The peripheral ring may include an axial guide rib, which may come into contact with the cylindrical surface of revolution of the body. Preferably, the peripheral ring comprises two sets of diametrically opposed axial guide ribs, each set preferably comprising three axial ribs.

[0038] The axial rib or ribs are preferably located between the first sealing joint and the second annular lip.

[0039] The insert head may include an annular lip engaged on the cylindrical surface of revolution of the body, and a cylindrical upright on which an annular lip of the cap is engaged.

[0040] The container may include a cannula attached to the insert at its proximal end, and received in a housing of the cap at its distal end.

[0041] The container may contain a cosmetic composition, for example a makeup or skincare composition, including a liquid foundation, a lipstick, a sunscreen product or an anti-wrinkle product.

[0042] The container can constitute a cartridge for a dispenser comprising an actuator for rotating the cap relative to the body. In this case, the cap may have at least one drive relief, in particular teeth, and the body preferably has at least one relief configured to immobilize the body in the dispenser.

[0043] The invention also relates to a dispenser comprising at least one container according to the invention. Brief description of the drawings

[0044] The invention will be better understood upon reading the detailed description that follows, a non-limiting example of its implementation, and upon examination of the accompanying drawing, in which:

[0045] [Fig-1] [Fig.1] schematically represents, in perspective, an example of dispenser receiving several containers according to the invention,

[0046] [Fig.2] [Fig.2] is a longitudinal section of an example of a container according to the invention,

[0047] [Fig.3] [Fig.3] shows in isolation, in partial longitudinal section, the insert of the container of [Fig.2],

[0048] [Fig.4] [Fig.4] represents a detail of the insert of the container of [Fig.2],

[0049] [Fig. 5] [Fig. 5] shows in isolation, in axial section, the piston of the container of the [Fig.2], and

[0050] [Fig.6] [Fig.6] is a cross-section along VLVI of [Fig.5]. Description of the implementation methods

[0051] Figure 1 shows a distributor 1 arranged to receive a plurality of identical containers 10, one of which has been shown in Figures 2 to 6.

[0052] The different containers 10 contain different cosmetic compositions, and are for example three in number.

[0053] Distributor 1 is, for example, as described in application EP 4 086 189 AL

[0054] It includes, for example, as many electric actuators as there are containers, and a control circuit for these actuators allowing selective control of the quantity of composition dispensed from each container. In the example considered, these actuators are electric motors.

[0055] The distributor 1 comprises a housing 2 resting on a base 3. A cable 4 provides electrical power to the distributor.

[0056] The housing 2 may include an on / off button 6 and an indicator light 5 providing information on the operating status.

[0057] The container 10 shown in figures 2 to 6 comprises a body 20, elongated along a longitudinal axis X. This body 20 comprises a tubular part 21, having an internal cylindrical surface 22 of revolution around the axis X.

[0058] The body 20 is closed at its proximal end by a bottom 20a. Ribs 27 can project on the radially external surface of the tubular part 21, near the bottom 20a.

[0059] The tubular part 21 is extended opposite the bottom 20a by a thinned distal portion 23, used for mounting a cap 40 on the body 20.

[0060] The distal portion 23 has an annular rim 24 and the cap 40 has a mounting skirt 41, having a groove 41a snapped onto the rim 24. Thus, the cap 40 is retained axially on the body 20 while being able to rotate around the axis X relative to it.

[0061] The container 10 has a central insert 50 which has a threaded hollow rod 51 defining an internal channel 53 opening near the bottom 20a through radial and axial openings 52.

[0062] The stem 51 connects on the distal side to a head 54 which rotates with the cap 40.

[0063] A piston 30 is mounted on the threaded rod 51. This piston 30 has a hub 31 internally threaded, cooperating with a thread 51a of the rod 51, connected to a peripheral ring 32.

[0064] The crown 32 has a first lip 34, on the proximal side, and a second lip 35, on the distal side.

[0065] The crown 32 has, as can be seen in [Fig.5], a groove 37 for receiving a first sealing gasket 60, preferably in the form of an O-ring, as illustrated.

[0066] The throat 37 is located in the example considered on the first lip 34.

[0067] The latter has a chamfer 34a, on the proximal side, as seen in [Fig.2],

[0068] The second lip 35 has, on the distal side, a chamfer 35a.

[0069] Axial ribs 38 project onto the crown 32 between the first joint 60 and the second lip 35, as seen in [Fig.5] in particular.

[0070] These ribs 38 are arranged for example in the form of two sets of three diametrically opposed ribs, as illustrated in [Fig.6].

[0071] The ribs 38 are arranged to contact the cylindrical surface of revolution 22.

[0072] The head 54 of the insert 50 has a shoulder 54a, as seen in [Fig.3], which axially delimits a portion of smaller diameter on which is present an annular groove 54b for receiving a second sealing joint 70.

[0073] The head 54 has a transverse wall 54c which extends perpendicularly to the axis X. This wall 54c carries on the side opposite the rod 51 a tubular upright 57 of axis X, provided on its radially external face with a toothing 58, visible in particular on [Fig.4].

[0074] The piston 30 has on its distal side an annular lip 36, with a larger internal diameter than the threaded rod 51, directed towards the head 54 of the insert 50.

[0075] The wall 54c has an annular lip 59 on the side of the stem 51.

[0076] The channel 53 opens distally through a housing 53a, provided with a rim annular 53b.

[0077] A cannula 55 is fixed onto the head 54 by snapping one end of the latter into the housing 53a.

[0078] The cannula 55 is inserted at its distal end into a housing 48, defined by the body 42 of the cap.

[0079] The mounting skirt 41 has reliefs cooperating with the teeth 58, which helps to immobilize the cap 40 in rotation relative to the insert 50 and to ensure good transmission of torque between the two.

[0080] The cap has an annular lip 49 which applies to the radially inner surface of the upright 57.

[0081] The cap 40 has an end piece 43, through which an internal channel 44 passes. The end piece 43 has teeth 45, which extend axially back from the distal end of the end piece, so as to provide a free surface 43a. The latter has an annular groove in which a sealing gasket 90 is received.

[0082] A removable closure cap 100 is mounted on the cap 40, for example by snapping, and has an annular lip 101 which applies to the seal 90.

[0083] A cover 80 can be attached to the bottom 20a, as illustrated in [Fig.2].

[0084] The outer diameter of the lips 34 and 35 may be slightly smaller than the diameter of the cylindrical inner surface of revolution 22 of the body 20. For example, the diameter of the surface 22 is 13.25 mm + / - 0.05 mm and the diameters of the lips 34 and 35 are 13.1 mm + / - 0.05 mm.

[0085] The presence of the lip 35 reduces the risk of the piston jamming when sliding inside the tubular part 21.

[0086] The presence of the chamfers 34a and 35a helps to limit friction on the surface 22.

[0087] The ribs 38 contribute to the guidance and reduce the risk of tilting of the piston 30 during its axial movement.

[0088] The seal 60 is slightly compressed between the piston 30 and the surface 22.

[0089] The body 20 can be made of PETG (polyethylene terephthalate copolymer).

[0090] The piston 30 and the insert 50 can be made of a non-polyolefin material, for example in PBT (polybutylene terephthalate).

[0091] The seal 60 can be made of a fluoropolymer.

[0092] The diameter of the circular section of the seal 60 (torus diameter) is, for example, 1 mm, and it is, for example, mounted in a groove deeper and wider than recommended for static mounting, so as to reduce the friction induced by the presence of the seal, for example, a groove 1.25 mm wide and 0.75 mm high. The rod head seal 70, for example, has a torus diameter of 0.5 mm, being received, for example, in a groove 0.8 mm wide and 0.4 mm high.

[0093] In the initial state, the piston 30 is positioned on the insert 50 as illustrated in [Fig.2], the lip 36 applying to the seal 70.

[0094] The compartment C, defined inside the body 20 between the piston 30 and the bottom 20a, is filled by an initial volume of composition.

[0095] This compartment C is isolated from the ambient air by the seals 60, 70 and 90, which allow for a prolonged storage period.

[0096] When the container 10 is inside the dispenser, the body 20 is for example immobilized in rotation relative to the housing 2 thanks to the presence of the ribs 27.

[0097] The teeth 45 of the cap 40 can mesh with a toothed wheel driven by an electric motor of the distributor. Thus, this motor allows the cap 40 to rotate relative to the body 20.

[0098] During this rotation, the piston 30 remains stationary relative to the body 20 due to the friction between the piston 30 and the surface 22, and the rotation of the rod 51 relative to the piston hub 31 causes the latter to move axially towards the bottom 20a. This results in a decrease in the volume of compartment C, which causes the composition to be expelled through the openings 52 into the interconnected channels 53, 56 and 44, until it exits through the distal end of channel 44, the cap 100 having been removed.

[0099] The presence of the seal 70 initially causes additional friction which, however, remains sufficiently low so as not to damage the cooperating threads of the rod 51 and the piston 30, or to rotate the piston with the screw.

[0100] During the movement of the piston 30, air can enter the body 20 between the piston 30 and the cap 40, thanks to a mounting clearance of the cap 40 on the body 20.

[0101] Of course, the invention is not limited to the example just described.

[0102] For example, seals 60 and 70 can be replaced by elastomeric seals other than O-rings, for example overmolded seals.

Claims

1.

2. Demands Container (10) comprising: - A body (20) having a tubular part (21) elongated along a longitudinal axis (X), intended to contain a fluid composition, open at its distal end, the tubular part (21) having an internal cylindrical surface (22) of revolution, - A cap (40) mounted on the tubular part (21) on its distal end, so as to be able to rotate relative to the tubular part, - A central insert (50) comprising a hollow stem (51) having an external thread (51a), the hollow stem being open at its proximal end, the central insert rotating with the cap, the hollow stem being extended on the distal side by a head (54) fixed in the cap, - A piston (30) mounted on the threaded rod (51), comprising an internally threaded hub (31) engaged on the external thread (51a) of the hollow rod (51), and a peripheral ring (32) extending opposite the cylindrical inner surface (22), the piston being axially movable along the hollow rod between an initial position where it is in contact with the head (54) and a final position where it is close to the proximal end of the threaded hollow rod, - A first sealing gasket (60), made of elastomer, carried by the peripheral ring (32), interposed between the peripheral ring and the cylindrical surface (22), the friction of the piston (30) on the tubular part (21) being sufficient to immobilize the piston in rotation relative to the tubular part while allowing it to move axially on the hollow threaded rod (51) during the relative rotation of the body (20) and the cap (40), - A second sealing gasket (70), made of elastomer, interposed between the piston (30) and the head (54) of the insert (50) when the piston is in its initial position. Container according to claim 1, the first sealing joint (60) being an O-ring.

3. Container according to any one of claims 1 and 2, the second sealing ring (70) being an O-ring.

4. Container according to any one of the preceding claims, the second sealing ring (70) being carried by the head (54) of the insert.

5. Container according to claim 4, the piston (30) having a sealing lip (36) extending from the hub (31) on the distal side, this lip applying to the second sealing seal when the piston is in its initial position.

6. Container according to any one of the preceding claims, the peripheral ring (32) of the piston having on the proximal side of the ring a first annular lip (34) opposite the cylindrical surface of revolution (22).

7. Container according to claim 6, the first lip (34) having a chamfer (34a) on the proximal side.

8. Container according to any one of the preceding claims, the peripheral ring (32) of the piston having on the distal side of the ring a second annular lip (35) opposite the cylindrical surface of revolution (22).

9. Container according to claim 8, the second lip (35) having a chamfer (35a) on the distal side.

10. A container according to any one of claims 8 and 9, the second lip (35) having an annular groove (37) receiving the first sealing ring (60), this groove preferably being wider and / or deeper than the nominal dimensions of the groove corresponding to a static mounting of the O-ring

11. Container according to any one of the preceding claims, the peripheral ring (32) having an axial guide rib (38) in contact with the cylindrical surface of revolution of the body.

12. Container according to claim 11, the peripheral ring comprising two sets of diametrically opposed axial guide ribs (38), each set preferably comprising three axial ribs.

13. Container according to one of claims 11 and 12 on the one hand, and one of claims 6 and 7 on the other hand, the axial rib or rib (18) being located between the first sealing joint (60) and the second annular lip (35).

14. Container according to any one of the preceding claims, the head of the insert comprising an annular lip (59) engaged on the cylindrical surface of revolution (22), and a cylindrical upright (57) on which is engaged an annular lip (49) of the cap (40).

15. Container according to any one of the preceding claims, comprising a cannula (55) attached to the insert at its proximal end, and received in a housing (48) of the cap at its distal end.

16. Container according to any one of the preceding claims, containing a cosmetic composition.

17. Container according to any one of the preceding claims, the piston (30) being made of a non-polyolefin thermoplastic material, in particular PBT.

18. Container according to any one of the preceding claims, constituting a cartridge for a dispenser (1) comprising an actuator for rotating the cap relative to the body.

19. Container according to the preceding claim, the cap having at least one drive relief (45), in particular a toothed one, the body preferably having at least one relief (27) configured to immobilize the container in the dispenser.

20. Dispenser comprising at least one container as defined in one of claims 18 and 19.