WO2021099375A1 - Container closure - Google Patents

Abstract

The invention relates to an aerosol dispenser (11) having a plastic container (13), which comprises a first end in the form of a bottom and a second, open end in the form of a neck (19), and a plastic valve cap (15), which has a valve and can be welded to the container (13) by means of a friction welding process. On the container neck (19) are formed a first tongue (29) and a first groove (31), which interact with a second groove (43) and a second tongue (41) formed on the underside of the valve cap (15) facing the container neck (19), in order to connect the valve cap (15) to the container (13) by the first tongue (29) engaging in the second groove (43) and the second tongue (41) engaging in the first groove (31).

Description

Container closure

Field of invention

The invention relates to an aerosol dispenser according to the preamble of claim 1.

State of the art

From the prior art in the field of aerosol containers, outer containers made of plastic are known, from which a filling material is conveyed out of the container by a propellant gas. The outer container is closed by a plastic valve cap with a valve. In the outer container there is a bag in which the contents are filled. In the cavity between the bag and the container Aussenbe the propellant gas is abandoned. The propellant exerts pressure on the bag, which forces the contents out of the bag when the valve is opened.

So that the aerosol container is closed in a gas-tight or filling-material-tight manner by the valve cap, the outer container, the valve cap and the bag are made from plastics that can be welded to one another. For this purpose, the valve cap has an outer and an inner radial welding protrusion formed on its underside. The outer projection can be welded to the outer container and the inner projection to the bag by means of a friction welding process.

This aerosol container is expensive to manufacture, however, since the valve cap must be designed in such a way that it can be welded to the outer container and the bag. Contamination of the product with abraded plastic chips, which can occur during friction welding, is also not reliably prevented. In addition, the projections and their seats on the outer container and the bag must be manufactured very precisely so that the valve cap does not sit askew on the outer container.

At the end of the invention

The disadvantages of the described prior art result in the task of proposing an aerosol dispenser which provides a simple seal between the sen container and the valve cap and at the same time a straight seat of the valve cap on the outer container is made possible and contamination of the product with plastic chips is prevented.

Description

The problem posed is achieved in an aerosol dispenser by the features cited in the characterizing section of claim 1. Developments and / or advantageous design variants are the subject of the dependent claims.

The invention is preferably characterized in that a first spring and a first groove formed on the container neck, usammenwirken which the second groove and formed with a on the side facing the container neck underside of the valve cap second spring _Z to connect to the valve cap to the container by engaging the first tongue in the second groove and the second tongue in the first groove. Between the first tongue and the second groove, a non-detachable and filling material-tight connection can be established, even if the filling material is under pressure in the interior of the container. This connection is preferably produced by a friction welding process in which the plastics of the valve cap and the container merge into one another. However, other types of connection, such as gluing or welding with an auxiliary material, are also conceivable. The interaction of the second tongue with the first groove serves to collect impurities, in particular swarf, which arise when the dispenser is closed. By collecting the impurities in the first groove and closing it with the second tongue, the product is reliably protected from contamination by the impurities. So that this protection works, the first groove and the second tongue are arranged closer to the longitudinal axis of the container than the first tongue and the second groove.

In a particularly preferred embodiment of the invention, the end of the first spring has, in cross section, the shape of a first trapezoid with first legs. As a result, the first tongue has the largest possible contact area with the second groove. The shape of an isosceles trapezoid is preferred, in which definiti- Onsgemäß the first legs are of the same length or in which the two Innenwin angles are the same on one of the parallel base sides. Other trapezoidal shapes, such as a right-angled trapezoid, are also conceivable.

In a further particularly preferred embodiment, the bottom of the two th groove has the shape of a second trapezoid with second legs in cross section. This allows the first tongue to be inserted deeply into the second groove for connection.

The invention is also preferably characterized in that the first and second legs are flush with one another when the valve cap is placed on the container neck. This means that the interior angles of the first and the second trapezoid are equal. This ensures that the contact surface of the first and second legs is as large as possible and consequently a particularly stable welded connection can be produced between the valve cap and the container neck. With this design of the first and second trapezoid, the two welding partners are centered on each other when they are assembled.

The first tongue and the second groove are expediently dimensioned in such a way that a first cavity is formed in the second groove when the valve cap is placed on the neck of the container. Therefore the second legs are longer than the first legs. During friction welding, the first tongue can therefore penetrate further and further into the second groove until it reaches the bottom of the second groove.

It has proven to be expedient if a second cavity is formed in the second groove, if the valve cap is welded to the container neck, in that the first tongue is welded to the second groove. The first tongue is therefore not inserted too deeply into the second groove and the contact pressure between the first and second legs remains high during the friction welding due to their wedge shape, whereby a high level of friction is generated. The high friction means that the melting points of the plastics are reliably reached.

Because the height of the first trapezoid is preferably smaller than the height of the second trapezoid, the first cavity described above can be formed.

It proves to be advantageous if the first groove and the first tongue or the second groove and the second tongue are arranged next to one another. As a result, the A handle elements are arranged to save as much space as possible. Conveniently, the first tongue and the first groove are formed on the end face of the Behäl terhalses. This embodiment also enables the engagement elements to be arranged on the container neck in a space-saving manner as possible.

In a further preferred embodiment of the invention, a third tongue is formed on the end face of the container neck and a third groove is provided on the underside of the valve cap, in which the third tongue can engage. As a result, the engagement elements can together form a labyrinth seal which reliably retains chips in front of the interior of the container.

The first groove is advantageously delimited by the first and third tongue. It is also advantageous if the second tongue is delimited by the second and third groove. As a result, a labyrinth seal can be realized which only takes up the wall thickness of the container neck as space requirement.

In a particularly preferred embodiment of the invention, the first, second and third tongue and the first, second and third groove are circular and have a common axis of rotation when the valve cap is placed on the container neck. As a result, the valve cap can be rotated relative to the container neck, which is unavoidable for the friction welding process.

In a further particularly preferred embodiment of the invention, the middle diameters of the first tongue and the second groove are the same size and the mean diameters of the first groove and the second tongue are the same size. As a result, the springs engage in the middle of the grooves and two annular chambers are formed. In the annular chamber between the first groove and the second tongue, the welding chips are insulated, which are rubbed off between the first and the second trapezoid during the friction process. Conveniently, a circular shoulder is formed on the edge of the valve cap, on which the second tongue and the second and third groove are formed. The shoulder provides the space that is necessary so that the engagement elements of the valve cap can be formed exactly over the engagement elements of the container neck.

In a further preferred embodiment of the invention, the valve cap has a first cylindrical wall which can protrude into the container neck and the valve cap is centered on the container neck. The first cylindrical wall is preferably conical formed, whereby this centering takes place automatically when the valve cap is put on and takes place in addition to the centering by the first tongue with the second groove.

It has proven to be expedient if the shoulder extends between the first cylindrical wall and a second cylindrical wall. The second wall protects the welded connection between the first tongue and the second groove from mechanical damage, since the second wall overlaps the container neck.

The invention is also preferably characterized in that engagement means are provided on the valve cap, on which a tool can engage in order to set the valve cap in rotation relative to the container. As a result, the valve cap can be friction-welded to the container neck by inserting a corresponding tool into the engagement means of the valve cap. The rotational movement is preferably an oscillating rotary movement with an angle of rotation of 90 degrees each.

Further advantages and features emerge from the following description of two exemplary embodiments of the invention with reference to the schematic representations. It shows in a representation that is not true to scale:

FIG. 1: a perspective view of an aerosol dispenser with a loading container in the form of a preform and a valve cap which can be welded to the container neck;

FIG. 2: a section through the valve cap and the container neck;

FIG. 3: a detailed view of the connection between the container neck and the valve cap from FIG. 2 when the valve cap is placed on the container;

FIG. 4: a detailed view of the connection between the container neck and the valve cap from FIG. 2 when the valve cap is welded to the container in a first embodiment; FIG. 5: a detailed view of the connection between the container neck and the valve cap from FIG. 2 in a second embodiment;

FIG. 6: a detailed view of the connection between the container neck and the valve cap from FIG. 2 in a third embodiment;

FIG. 7: the container in a side view in the form of a plastic bottle with a correspondingly shaped container neck;

FIG. 8: the container in a side view in the form of a preform with a correspondingly shaped container neck;

FIG. 9: the container neck from FIG. 5 or 6 enlarged and partially cut open;

FIG. 10: the end face of the container neck in a detailed view and FIG. 11: a detailed view of the valve cap.

In the figures 1 to 4 an aerosol dispenser is shown, which is designated as a whole with the reference numeral 11. The aerosol dispenser 11 has a container 13 and a valve cap 15. The container 13 is shown as a preform in FIGS. 1 and 6, but can also be a bottle (FIG. 5). The container 13 comprises a first end which is designed as a bottom 17 and a second end which is designed as a neck 19.

The valve cap 15 is equipped with a valve 21 in its center. In the Behäl ter 13 a product can be filled. To expel the filling material, a piston can be arranged in the container 13 (not shown in the figures), which divides the inner space 23 in a gas-tight manner into a gas space and a filling material space. A propellant gas is filled in the gas space and the filling material is filled in the filling material space. If the valve is opened, the piston driven by the propellant gas moves upwards and pushes the filling material through the valve 21. The container 13 and the valve cap 15 are each made of a plastic, and the plastics can be welded together. By rapidly oscillating about the longitudinal axis 25 relative to the container 13, at the contact surfaces between the container neck 19 and the valve cap 15 generates such a high degree of frictional heat that the plastics melt together and the valve cap 15 is welded to the container neck 19.

A first tongue 29, a first groove 31 and a third tongue 33 are formed on the end face 27 of the container neck 19. The first and third tongue 29, 33 are preferably separated from one another by the first groove 31. The first and third tongue 29, 33 and the first groove 31 preferably have the shape of a circular ring with the longitudinal axis 25 as the center. The longitudinal axis can therefore also be regarded as an axis of rotation 25.

A shoulder 35 is formed on the outer edge of the valve cap 15 and is positioned between a first inner cylindrical wall 37 and a second outer cylindrical wall 39. A second tongue 41 and a second and third groove 43, 45 are formed on the circular shoulder 35.

The end of the first spring 29 has, in cross section, the shape of a first trapezoid 47 with first legs 49a, 49b. The base of the second groove 43 has, in cross section, the shape of a second trapezoid 51 with second legs 53a, 53b. The two trapezoids 51, 53 are preferably isosceles trapezoids, but the trapezoids can also be right-angled, for example, or the first or second legs can also have a different position relative to one another.

As FIG. 3 shows, the first legs 49a, 49b lie flush with the second legs 53a, 53b when the valve cap 15 is placed on the container neck 19. The interior angles of the first legs 49a, 49b are therefore preferably the same size as the interior angles of the second legs 53a, 53b. The flush contact of the legs 49, 53 enables the valve cap 15 to be automatically centered with the container neck 19 before the start of welding. A large friction surface is also formed between the first and second legs. If the attached valve cap 15 is set in rotation relative to the container neck 19, frictional heat arises between the first legs 49a, 49b and the second legs 51a, 51b, which melt the plastics of the valve cap 15 and the container 13. The first tongue 29 is therefore friction-welded to the second groove 43, and the valve cap 15 is thus filled with the container 13 in a sealed manner connected. The welded joint is tight even if the product filled into the dispenser 11 is under a pressure which is necessary to push the product through the valve 21 out of the dispenser 11.

When the valve cap 15 is placed on the container neck 19, the first tongue 29 protrudes only far enough into the second groove 43 that a first hollow space 55 is formed at the bottom of the second groove 43. The height 57 of the first trapezoid 47 is therefore smaller than the height 60 of the second trapezoid. During the friction welding, the first tongue 29 penetrates the second groove 43, as a result of which the first cavity 55 is reduced in size to form a second cavity 59. The first tongue 29 can also be driven to the bottom of the second groove 43 (FIG. 5) and beyond (FIG. 6), as a result of which there is no longer a second cavity 59.

In FIG. 5, the first tongue 29 is pressed in to the bottom of the second groove 43. This creates a weld seam 62. The pressure and the resulting friction weld connection can be continued even further until the first tongue 29 completely fuses with the second groove 43 (FIG. 6). FIGS. 3 to 6 show that the second and third tongue 41, 33 penetrate further and further into the first and third groove 31, 45, the more pronounced the friction welding is. As a result, the labyrinth seal formed by the plurality of grooves and tongues is sealed better and better and passages are completely closed. It is therefore impossible that chips 64 produced during the friction welding penetrate into the interior 23 and contaminate it. This is also advantageous in that the deeper the valve cap 15 and the end face 27 interlock or the more weld chips 64 arise, the sealing device becomes more tight.

The mean diameters of the first annular spring 29 and the second annular groove 43 are the same size and correspond to a first diameter 61. The mean diameters of the second annular spring 41 and the first annular groove 31 are the same size and correspond to a second diameter 63 The mean diameters of the third circular tongue 33 and the third circular groove 45 are of the same size and correspond to a third diameter 65. In addition, the first tongue 29, the first groove 31 and the third tongue 33 are arranged next to one another or on the container neck 19. on the valve cap 15, the second groove 43, the second tongue 41 and the third groove 45 are arranged next to one another. This allows a System of springs and grooves are formed, which interlock and function on the principle of a labyrinth seal. Chips 64, which are formed during the friction welding, especially when the first and second legs 49,53 interact, are caught in the first groove 31. During the friction welding, the first groove 31 is completely closed by the second tongue 41. Penetration of chips 64 into the interior 23, which could contaminate the filling material, is reliably prevented by the design of the labyrinth seal.

The shoulder 35 is delimited on its side closer to the longitudinal axis 25 by the first cylindrical wall 37. The first wall 37 preferably has a conical shape, as a result of which the valve cap 15 is centered on the container neck 19 in addition to the centering function of the trapezoids 47, 51 when it is placed on the container neck 19. The second cylindrical wall 39, which covers the first spring 29 and accordingly protects against mechanical damage, closes on the outside of the shoulder 35. Engagement means 71 are provided on the top of the valve cap 15. A tool can intervene at this A handle means 71, which can set the valve cap 15 in a rotational movement about the axis of rotation 25 when the valve cap 15 is placed on the container neck 19. This can be, for example, an oscillating Drehbewe supply by 90 degrees. It is also conceivable that the tool exerts a pressure along the axis of rotation 25 on the valve cap 15 in order to increase the friction between the first and second trapezoidal legs 49, 53. As a result, the first spring 29 is friction-welded to the second groove 43. The valve cap 15 and the container 13 are preferably made of polyethylene terephthalate (PET) or polyethylene furanoate (PEF), which plastics can be welded together. The design of the connecting elements between the valve cap 15 and the loading container neck 19 as a first in cross-section trapezoidal spring 29 and as a second in cross-section trapezoidal groove 43 enables reliable friction welding. The design of the connecting elements as a labyrinth seal ensures that weld chips 64 produced during welding are retained in the labyrinth seal and cannot get into the product. Lee end:

11 aerosol dispensers

13 container, bottle, preform

15 valve cap

17 Bottom of the container

19 neck of the container

21 valve

23 interior

25 longitudinal axis, axis of rotation

27 front side

29 First spring

31 First groove

33 Third spring

35 paragraph

37 First cylindrical wall

39 Second cylindrical wall

41 Second spring

43 Second groove

45 Third groove

47 First trapeze

49a, 49b First leg 51 Second trapezoid

53a, 53b Second leg

55 First cavity

57 Height of the first trapezoid

59 Second cavity

60 Height of the second trapezoid 61 First diameter 62 Weld seam

63 Second diameter

64 chips

65 third diameter 71 engagement means

Claims

Claims Aerosol dispenser (11) comprising a container (13) made of a plastic, which comprises a first end designed as a base (17) and a second open end designed as a neck (19) and with a valve cap (15) made of a plastic a valve (21) which can be welded to the container (13) by a friction welding process, characterized in that a first tongue (29) and a first groove (31) are formed on the container neck (19), which with a second groove (43) and second tongue (41) formed on the underside of the valve cap (15) facing the container neck (19) interact to connect the valve cap (15) to the container (13) by the first spring ( 29) engages in the second groove (43) and the second tongue (41) engages in the first groove (31). Dispenser according to Claim 1, characterized in that the end of the first spring (29) in cross section has the shape of a first trapezoid (47) with first legs (49a, 49b). Dispenser according to Claim 1 or 2, characterized in that the base of the second groove (43) has the shape of a second trapezoid (51) with second legs (53a, 53b) in cross section. Dispenser according to Claim 3, characterized in that the first and second legs (49a, 49b, 53a, 53b) lie flush against one another when the valve cap (15) is placed on the container neck (19). Dispenser according to one of the preceding claims, characterized in that the first tongue (29) and the second groove (43) are dimensioned such that a first cavity (55) is formed in the second groove (43) when the valve cap (15 ) is placed on the container neck (19). 6. Dispenser according to one of the preceding claims, characterized in that a second cavity (59) is formed in the second groove (43) when the valve cap (15) is welded to the container neck (19) by the first spring ( 29) is welded to the second groove (43). 7. Dispenser according to one of claims 3 to 6, characterized in that the Height (57) of the first trapezoid (47) is smaller than the height (60) of the second trapezoid (51). 8. Dispenser according to one of the preceding claims, characterized in that the first groove (31) and the first spring (29) or the second groove (43) and the second spring (41) are arranged side by side. 9. Dispenser according to one of the preceding claims, characterized in that the first spring (29) and the first groove (31) are formed on the Sürnseite (27) of the Behäl terhalses (19). 10. Dispenser according to claim 9, characterized in that a third spring (33) is formed on the end face (27) of the container neck (19) and a third groove (45) is provided on the underside of the valve cap (15), in which the third spring (33) can intervene. 11. Dispenser according to claim 10, characterized in that the first groove (31) is delimited by the first and third tongue (29, 33). 12. Dispenser according to one of claims 10 or 11, characterized in that the second spring (41) is delimited by the second and third groove (43, 45). 13. Dispenser according to one of claims 10 to 12, characterized in that the first, second and third tongue (29,41,33) and the first, second and third groove (31,43,45) are circular and have a common axis of rotation ( 25) when the valve cap (15) is placed on the container neck (19). 14. Dispenser according to one of the preceding claims, characterized in that the mean diameter (61) of the first spring (29) and the second groove (43) are the same size and the mean diameter (63) of the first groove (31) and the second tongue (41) are the same size. 15. Dispenser according to one of claims 10 to 14, characterized in that a circular shoulder (35) is formed on the edge of the valve cap (15), on which the second tongue (41) and the second and third groove (43, 45) are formed. 16. Dispenser according to one of the preceding claims, characterized in that the valve cap (15) has a first cylindrical wall (37) which can protrude into the container neck (19) and centers the valve cap (15) on the container neck (19). 17. Dispenser according to one of claims 15 or 16, characterized in that the shoulder (35) extends between the first cylindrical wall (37) and a second cylindrical wall (39). 18. Dispenser according to one of the preceding claims, characterized in that engagement means (71) are provided on the valve cap (15), on which a tool can engage in order to set the valve cap (15) in rotation relative to the container (13) .