Reclosable cap to be mounted on a spout of a container

Abstract

Shown and described is a reclosable cap (1) to be mounted on a spout of a container, comprising - a cylindrical lateral wall (2) extending around an axis (Z) and a top wall (3) positioned at one end of the lateral wall (2), - a first separating line (SL1) provided circumferentially around the lateral wall (2) to define an anchor ring (8) and a lid (4), wherein the first separating line (SL1) extends between a first end section (12) and a second end section (13), the end sections (12, 13) being spaced apart from each other circumferentially to provide a connection portion (14) connecting the anchor ring (8) and the lid (4), and - a second separating line (SL2) provided circumferentially around the lateral wall (2) between a first and a second end, substantially parallel to the first separating line (SL1) and located on the anchor ring (8). In order to configure and further develop a reclosable cap (1) with a simple design and cheaper production costs without the risk of breakup of the tether arms (8A) and to achieve an improved force distribution at the ends of the separating lines (SL1 and SL2), the end sections (12, 13) each span an angle γ > 6° of the circumference of the lateral wall (2) and define a transition from full wall thickness of the connection portion (14) to the first separating line (SL1), and wherein each end section (12, 13) is bordered axially by reinforcing sections (RS) which have substantially the same lateral wall thickness as the connection portion (14), measured radially.

Description

[0001]January 17, 2024Reclosable cap to be mounted on a spout of a containerThe invention relates to a reclosable cap to be mounted on a spout of a container,comprising- a cylindrical lateral wall extending around an axis and a top wall positioned at oneend of the lateral wall,- a first separating line provided circumferentially around the lateral wall to definean anchor ring and a lid, wherein the first separating line extends between a firstend section and a second end section, the end sections being spaced apart fromeach other circumferentially to provide a connection portion connecting theanchor ring and the lid, anda second separating line provided circumferentially around the lateral wall between afirst and a second end, substantially parallel to the first separating line and located onthe anchor ring.For the last few years, there has been a need to ensure that small pieces of plasticcannot be released separately into the environment (EU Directive 2019 / 904).Therefore, plastic lids of containers must be connected to the respective spoutelement by means of connecting bands in order to reliably avoid separation of suchlids.Reclosable caps for bottles or as part of pouring elements for containers, e.g., beveragecontainers, have long been known in many variations. Such pouring elementscomprise in general a base element with a flange to be sealed onto the surface of apackage, e.g., a carton / polymer-composite package, and a spout with a pouringopening wherein the pouring opening is opened and reclosed by a cap, e.g. a screwcap. These pouring elements additionally have an opening element, e.g., a cuttingelement, arranged inside the spout. Such an opening element opens the packageduring the initial opening by means of a reclosable cap.The cutting element may be shaped as cutting ring movably guided inside the spoutand driven by unscrewing the reclosable cap. The rotation of the cap, generally in ananti-clockwise direction, is used to rotate the cutting ring in the direction onto thesurface of the package. In the area of the later opening, a package might comprise a socalled “overcoated hole” (OCH) consisting of a hole in the carton material beinglaminated with a thin plastic layer, e.g., made from polyethylene (PE), on both sides ofthe carton layer. Other packages may be provided with weakened zones, e.g.,perforations, in order to allow an easier cutting of the package material during theinitial opening of such packages.In order to ensure that the reclosable caps of packages do not enter the environmentunintentionally, it is desirable to secure these screw caps to their respective packageso that loose plastic parts are reliably avoided even when the package is open.Elements which ensure a secure fastening of screw caps to their respective packageeven in the opened state have long been known from the prior art in the area ofclosures for commercially available PET bottles. What the known PET bottles have incommon is that the cylindrical main body has a bottle neck which is significantlynarrower than the main body, so that a screw cap provided with a fastening elementcan be pivoted away significantly over 120°.A closure device for a PET bottle with a ring arranged under the screw cap is knownfrom EP 1124734 B1, said ring being connected to the screw cap via a film hinge andpreventing the screw cap from being pulled off even in the opened state.US 5215204 A shows a closure cap for a bottle with a ring arranged under the screwcap, said ring being connected to the screw cap in a materially-bonded manner via twoTH / ha 230291WO17 January 2024connecting bridges. The ring and the bottle are designed in such manner that the ringcannot be pulled off the bottle.Another cap for closing a container is known from WO 2021 / 014287 A1. This genericcap comprises a side wall and a top wall forming a closure element and a retainingring to ensure that the cap remains anchored to a neck of a container provided with aspout element being part of or adhered to said container. The cap is separated by afirst separating line from the retaining ring wherein a second separating line,arranged substantially parallel to the first separating line, forms connecting bands aspart of the retaining ring in order to allow an easier handling during opening andreclosing the cap.Since such caps might be opened and reclosed repeatedly, the ends of these separatinglines and thus the connection bands may be damaged or even destroyed in case ofhigh and / or repeated forces on the connecting bands. In the past, different solutionshave been found in order to minimize the stress in the cut endings, e.g., roundedendings are known from WO 2021 / 014287 A1. The aforementioned solutions aredemanding and complex to produce. Another reclosable container cap is known fromEP 3689774 A1. However, its design is even more complex than the aforementionedsolutions. It also specifically weakens the walls near the ends of the separating lines sothat the cap can be opened up to 180° pivot angle more easily.Based on this, the object underlying the present invention is to configure and furtherdevelop a reclosable cap with a simple design and cheaper production costs withoutadditional risk of breaking the connecting bands. Furthermore, it is desirable toachieve an improved force distribution at the ends of the separating lines so that noforce spikes are introduced in these relatively weak areas of the cap.These objects are achieved in the case of a reclosable cap element with the features ofthe preamble of claim 1 in that the end sections each span an angle γ > 6° of thecircumference of the lateral wall and define a transition from full wall thickness of theTH / ha 230291WO17 January 2024connection portion to the first separating line, and in that each end section is borderedaxially by reinforcing sections. The reinforcing sections specifically ensure that theforces acting on this border region will be distributed as evenly as possible. Thepolymer wall can still deform plastically, but in a more spread-out manner, e.g., alonga bigger stretch of the tether arms below the first separating line. This inhibits stressspikes from forming and damaging a single part of or around the tether bands whichcould lead to tears and complete breakage of the tether. The aforementioned stress-whitening is simply the first step in this process, especially when opening andreclosing the tethered cap several times.The end sections have a transition from full wall thickness to a very thin skin, beforeending in the first separating line. The transition itself already serves to distributeforces more evenly rather than concentrating them into a single point. Moreover, thementioned thin skin at the ultimate area of the end zone allows small damage to occur(when opening the cap) in a sort of predetermined breaking point or simply bystretching the skin. The beginnings of such a small crack then gets stuck in theincreasing wall thickness of the end zone, rather than branching out and tearing intoweaker parts. Again, this gets even more pronounced with the addition of thereinforcing sections which funnel this controlled force propagation along. A short endas it was known in the prior art directs forces introduced during opening straightacross the wall of the cap, whereas the present invention allows for such forces to bemore spread out and directed partly along the circumferences.A further teaching of the invention provides that the reinforcing sections havesubstantially the same lateral wall thickness as the connection portion, measuredradially. This allows for a simplified production where the positioning of theseparating lines and the cap itself does not need to be aligned perfectly duringproduction.In a particularly preferred configuration of the invention, the end sections each span an angle γ > 8° of the circumference of the lateral wall in order to achieve a sufficient TH / ha 230291WO17 January 2024 force distribution. The longer end zones also guarantee reinforcing sections as theseat least span the same length. Preferred angle ranges are 6° < γ < 12° or 8° < γ < 15°,respectively.According to another preferred configuration, the first and the second end sections ofthe first separating line are formed by a gradual reduction in wall thickness along acircumferentially direction.A preferred design of the invention provides that the connection portion spanscircumferentially an angle δ of 20 to 40°. This ensures that the connection portion canact as reliable hinge for the cap during pivoting open and later closing thereof. On theother hand, a connection portion that spans at most 40° ensures the flexibility of it andthe adjacent reinforcing sections stays high enough that no additional forces areintroduced inherent with a bigger and thus stiffer connection portion. Preferably, theratio of δ / γ is between 2.8 and 3.5. Tests have shown that ratios in this range with arather small connection portion further increase the advantage detailed above. Forexample, a ratio of 3 means that the end and reinforcing sections make up 40% of thecircumferential distance (delta + 2 gamma). These relatively large end sections directthe resulting forces further away and into the side wall, rather than towards thecentral axis.A further teaching of the invention is characterised in that the first separating line andthe second separating line overlap in the circumferential direction and in that theconnection portion is arranged substantially in the centre of the second separatingline. This allows a symmetric design and an optimized function of the reclosable cap.According to a further preferred embodiment of the invention, the parallel ends ofboth the first separating line and the second separating line define two tether arms inthe anchor ring between the connection portion and the wider part of the anchor ring,and in that the distance between the first and second separating lines is constantalong the full length of both tether arms. Preferably, the tether arms each spanTH / ha 230291WO17 January 2024circumferentially an angle of 50 to 75° of the circumference of the lateral wall. Such asolution allows that the tether arms may be twisted during pivoting-open of the capwithout undue localised stress. It also ensures that the tether arms outside of thereinforcing sections still offer enough freedom to move and pivot the caps.In a particularly preferred configuration of the invention, the connection portion andthe reinforcing sections have a stronger lateral wall thickness than the remaininglateral wall of the anchor ring. Due to the reinforcing sections damage and stress-whitening along the axial direction are impeded or prevented and a stressconcentration in single weak points is reliably eliminated. Preferably, the reinforcingsections extend along at least half of the length of each tether arm.According to a preferred embodiment of the reclosable cap according to the invention,another ring is arranged below the anchor ring, which is connected to the anchor ringvia a plurality of material bridges and serves as a tamper-evident seal. The screw cap,the anchor ring and the additional ring serving as a tamper-evident seal aremanufactured in one piece in this case. Preferably, the ring can only be twisted to alimited extent by blocking ribs protruding inwards from the ring with lockingelements arranged over the circumference of the base element such that it is releasedfrom the anchor ring when the screw cap is unscrewed initially by tearing off thematerial bridges and remains in its position on the base element.Another preferred embodiment of a reclosable cap according to the inventionprovides that the cap in its pivoted-open state is locked at a maximum opening angleof 150° by the connection portion in relation to its closed state, preferably with aminimum of 120°. Such a locking is possible, since the connection portion gets flippedwith both tether arms twisted after pivoting open of the cap. In this state, thereclosable cap can no longer pivot back without applying a force externally. This hasthe great advantage that the cap does not pivot back automatically during pouring anddoes not come into contact with the product during the pouring process. Particularlyin this stage, the gradually extended end zones serve as reinforcement and reduceTH / ha 230291WO17 January 2024stress spikes in the region of the connection portion. While opening angles above 150°may be preferable in many cases, they also lead to even higher forces acting on theend sections. As such, limiting the opening angle to a maximum of 150° allows thereclosable cap more freedom in designing the most critical areas.A further teaching of the invention provides that such a cap is radially freely rotatablein its locked opening state. Though the connection portion is flipped over, it is stillpossible to freely rotate the cap even in this position. This has the great advantage thatthe screw cap can be turned to a position desired by the user. In the locked position, aslight force must still be applied externally in order to enable rotation, since anincreased frictional resistance between the connection portion and the spout resultsfrom the fixing of the screw cap in relation to its pivot opening. However, theincreased frictional resistance is also desired so that the screw cap does not easilymove in the direction of the pouring stream during pouring, caused by thegravitational force.In a particularly preferred design of the invention, each single tether arm canwithstand forces of at least 12 N. This ensures that even in case of one damaged ordestroyed tether arm the lid remains securely at the anchor ring. The forces should bemeasured according to EN 17665 and the minimum of 12N needs to be reached for asingle band with every type of measurement detailed in the norm. This guaranteesadditional security in that the norm will still be fulfilled even in adverse situationsdetailed above.The invention will be explained in more detail below on the basis of a drawing whichrepresents a preferred exemplary embodiment. In the drawing showFig. 1 an exemplary embodiment of a reclosable cap according to the inventionin an unopened state (without container) in perspective view,Fig. 2 the reclosable cap from Fig. 1 in a side view,TH / ha 230291WO17 January 2024Fig. 3 a partially broken view of the enlarged circle III from Fig. 1 in aperspective view,Fig. 4 the reclosable cap from Fig. 1 in a bottom view into the vertical sectionalong the line IV-IV in Fig. 2,Fig.5 the cap element from Fig.4 in a perspective view from below,Fig. 6 the reclosable cap from Fig. 1 in a bottom view into the vertical sectionalong the line VI-VI in Fig. 2,Fig.7 the cap element from Fig.6 in a perspective view from below, andFig. 8 the reclosable cap from Fig. 1 during pivoting up in a detailed side view,which is partially broken.Fig. 1 shows the perspective view of a reclosable cap 1 with a cylindrical (hollowcylinder) lateral wall 2 extending around an axis Z and a top wall 3 positioned at oneend of the lateral wall 2. The upper lateral wall 2 and the top wall 3 define a lid 4. Thereclosable cap 1 is mounted on a spout element 5 having a pouring tube (not shown)and a flange 6 extending radially around the pouring tube. The flange 6 allows sealingof the spout element 5 on a container, e.g., a carton / plastic-composite package forbeverages. In order to facilitate of unscrewing the cap 1, its upper surface in thetransition of the lateral wall 2 and the top wall 3 is provided with a corrugation 7.A first separating line SL1 provided circumferentially around the lateral wall 2 todefine an anchor ring 8. Below the anchor ring 8 a further ring 9 can be seen as part ofthe lateral wall 2 separated by a third separating line SL3. The ring 9 serves as atamper-evident element and therefore, can only rotate to a limited extend due toblocking ribs (not shown) protruding inwards from the ring 9 with lateral protrusionsTH / ha 230291WO17 January 202410 arranged over the circumference of the spout element 5. The ring 9 is connected tothe anchor ring 8 via a plurality of material bridges 11 which will break during initialof the cap 1. The first separating line SL1 extends between a first end section 12 andsecond end section 13, which will be shown in Fig. 2, a side view (without spoutelement) of the cap 1 of Fig. 1 for the sake of clarity. In the area without the firstseparating line SL1 between the end sections 12 and 13 a connection portion 14 isdefined. The end sections 12 and 13 are bordered axially on both sides by reinforcingsections RS, which have been shaded in the figures for clarification. A secondseparating line SL2 is provided circumferentially around the lateral wall 2substantially parallel to the first separating line SL1 and between the free edge of thelateral wall 2 and the first separating line SL1. The anchor ring 8 comprises an upperpart comprising two tether arms 8A (one shown in Fig. 2) and a lower part 8B. Thetether arms 8A have the same height over their full length.In the preferred embodiment shown, the first separating line SL1 and the secondseparating line SL2 overlap in the circumferential direction and it can be seen that theconnection portion 14 is arranged in (above) the centre of the second separating lineSL2.In order to better describe the particularities of the end sections 12 and 13, Fig. 3shows an enlarged perspective view of the circle III marked in Fig. 1. It can be clearlyseen that the first and the second end sections 12 and 13 of the first separating lineSL1 are formed by a gradual change in wall thickness wherein the end sections 12 and13 each span an angle γ = 8.85° of the circumference of the lateral wall 2 (10.45° in analternative embodiment not shown in the Figs.).The connection portion 14 is horizontally cut between the end sections 12 and 13. Thetwo lower reinforcement sections RS can be seen at the end of the tether arms 8B. Thewall thickness measured radially is substantially the same as that of the connectionportion 14, whereas the respective wall thickness inside the end sections 12 and 13gets progressively smaller. Since the spout element 5, which defines the pouring tube,TH / ha 230291WO17 January 2024is shown in the broken area, both the top part and the bottom part of the lateralprotrusion 10 can be recognized. Even if not shown, there may be also thin materialbridges in the separating lines SL1 and SL2.Fig. 3 additionally shows that the top wall 3 has a circumferential reinforcing rib 15and driving elements 16 which will be described in more detail below. Additionally, itcan be seen that the lateral wall 2 comprises an internal thread 17. This internalthread 17 acts together with an external thread 18 protruding outside of the lateralwall of the spout element 5.Fig. 4 shows the bottom view of the vertical section along the line IV-IV in Fig. 2. Itshows exactly the same situation of the first separating line SL1 shown in Fig. 3. In thisdrawing the gradual circumferential wall thickness reduction of the end sections 12and 13 are clearly shown. Each of the end sections 12 and 13 span an angle of γ =8.85° (or 10.45° in a further embodiment, not shown) of the circumference of thelateral wall 2. Moreover, the circular reinforcement 15 inside the cap 1 can be seenwhich comprises three driving elements 16 being also cut partially along the cuttingline IV-IV in Fig. 2. For a better understanding, the bottom view of Fig. 4 is illustratedas a perspective view from below in Fig. 5. This shows only the lid 4 as the view is cutexactly on the height of the first separating line SL1 which defines the lid 4 and theanchor ring 8 as part of the cap 1.Fig. 6 shows the reclosable cap from Fig. 1 in a bottom view of the vertical sectionalong the line VI-VI in Fig. 2, i.e., along the second separating line SL2. The lateral wall2 is interrupted partially by the separating line SL2. In the preferred embodiment, thesecond separating line SL2 spans an angle δ of appr. 165°. In Fig. 6, the drivingelements 16 are shown in full. For a better understanding, the bottom view of Fig. 6 isshown as a perspective view from below in Fig. 7. Here, the driving elements 16 areshown which drive, during the initial opening action, (and not shown) a cutting ringinside the spout element to provide an opening in the package under the pouring tubeof the spout element. Obviously, in an alternative embodiment of the reclosable cap 1TH / ha 230291WO17 January 2024both the circular reinforcement 15 and the driving elements 16 may be omitted if nocutting ring is needed for opening the package.Finally, Fig. 8 shows the reclosable cap 1 from Fig. 1 during opening of the lid 4 in adetailed side view of the connection portion 14 which is bent inwardly due to thelifting force onto the lid 4 at its free side. Here, the anchor ring 8 is shown with its twoelements, the tether arm 8A and the lower part 8B of the anchor ring 8. The gradualcircumferential wall thickness reduction at the end section 13 is shown more clearlyand, due to the inventive design of this area, stress spikes in the lateral wall 2 in theregion of the end section 13 are reliably reduced in order to smoothen the openingand reclosing of the lid 4. This position of the cap 1 also shows the stabilising andstiffening effect of the reinforcing sections RS during opening of the lid 4.TH / ha 230291WO17 January 2024 List of reference signs 1 Cap2 Lateral Wall3 Top Wall4 Lid5 Spout Element6 Flange7 Corrugation8 Anchor Ring8A Tether Arm8B Lower Part9 (Tamper Evident) Ring10 Lateral Protrusion11 Material Bridge12 First End Section13 Second End Section14 Connection Portion15 Reinforcing Rib16 Driving Element17 Internal Thread18 External ThreadRS Reinforcing SectionSL1 Separating LineSL2 Separating LineSL3 Separating LineZ Vertical AxisTH / ha 230291WO17 January 2024

Claims

January 17, 2024C l a i m s1. Reclosable cap (1) to be mounted on a spout of a container, comprising- a cylindrical lateral wall (2) extending around an axis (Z) and a top wall (3)positioned at one end of the lateral wall (2),- a first separating line (SL1) provided circumferentially around the lateralwall (2) to define an anchor ring (8) and a lid (4), wherein the firstseparating line (SL1) extends between a first end section (12) and a secondend section (13), the end sections (12, 13) being spaced apart from eachother circumferentially to provide a connection portion (14) connecting theanchor ring (8) and the lid (4), and- a second separating line (SL2) provided circumferentially around the lateralwall (2) between a first and a second end, substantially parallel to the firstseparating line (SL1) and located on the anchor ring (8),c h a r a c t e r i s e d i n t h a tthe end sections (12, 13) each span an angle γ > 6° of the circumference of thelateral wall (2) and define a transition from full wall thickness of the connectionportion (14) to the first separating line (SL1), and in that each end section (12,13) is bordered axially by reinforcing sections (RS).

2. Reclosable cap according to claim 1c h a r a c t e r i s e d i n t h a tthe reinforcing sections (RS) have substantially the same lateral wall thickness asthe connection portion (14), measured radially.

3. Reclosable cap (1) according to claim 1 or 2,ch a r a c t e r i s e d i n t h a t- 2 - the end sections (12, 13) each span an angle γ > 8° of the circumference of thelateral wall (2).

4. Reclosable cap (1) according to claim 3,ch a r a c t e r i s e d i n t h a tthe angular range is 8° < γ < 15°.

5. Reclosable cap (1) according to any of claims 1 to 4,c h a r a c t e r i s e d i n t h a tthe first and the second end sections (12, 13) of the first separating line (SL1) areformed by a gradual reduction in wall thickness along a circumferentiallydirection.

6. Reclosable cap (1) according to any of claims 1 to 5,ch a r a c t e r i s e d i n t h a tthe connection portion (14) spans circumferentially an angle δ of 20 to 40°.

7. Reclosable cap (1) according to claim 6,ch a r a c t e r i s e d i n t h a tthe ratio of δ / γ is between 2.8 and 3.5.

8. Reclosable cap (1) according to any of claims 1 to 7,c h a r a c t e r i s e d i n t h a tthe first separating line (SL1) and the second separating line (SL2) overlap in thecircumferential direction and in that the connection portion (14) is arranged inthe centre of the second separating line (SL2).

9. Reclosable cap (1) according to any of claims 1 to 8,c h a r a c t e r i s e d i n t h a tthe parallel ends of both the first separating line (SL1) and the second separatingline (SL2) define two tether arms (8A) in the anchor ring (8) between theTH / ha 230291WO17 January 2024- 3 - connection portion (14) and the wider part of the anchor ring (8), and in that thedistance between the first and second separating lines (SL1 and SL2) is constantalong the full length of both tether arms (8A).

10. Reclosable cap according to claim 9,c h a r a c t e r i s e d i n t h a tthe tether arms (8A) each span circumferentially an angle of 50 to 75° of thecircumference of the lateral wall (2).

11. Reclosable cap (1) according to claim 9 or 10,c h a r a c t e r i s e d i n t h a tthe reinforcing sections (RS) extend along at least half of the length of each tetherarm (8A).

12. Reclosable cap (1) according to any of claims 1 to 11,c h a r a c t e r i s e d i n t h a tthe connection portion (14) and the reinforcing sections have a stronger lateralwall thickness than the remaining lateral wall (2) of the anchor ring (8).

13. Reclosable cap (1) according to any one of claims 1 to 12,c h a r a c t e r i s e d i n t h a ta further ring (9) is arranged below a third separating line (SL3) under theanchor ring (8) and in that the ring (9) is connected to the anchor ring (8) via aplurality of material bridges (11) and serves as a tamper-evident seal.

14. Reclosable cap (1) according to any of claims 1 to 13,c h a r a c t e r i s e d i n t h a tthe cap (1) in its pivoted-open state is locked at a maximum opening angle of150° by the connection portion (14) in relation to its closed state.TH / ha 230291WO17 January 2024- 4 -15. Reclosable cap (1) according to claim 14,c h a r a c t e r i s e d i n t h a tthe cap (1) is radially freely rotatable in its locked opening state.

16. Reclosable cap (1) according to any of claims 1 to 15,c h a r a c t e r i s e d i n t h a teach single tether arm (8A) can withstand forces of at least 12 N.TH / ha 230291WO17 January 2024

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