US20150014318A1

US20150014318A1 - Low profile securing latch

Info

Publication number: US20150014318A1
Application number: US14/379,455
Authority: US
Inventors: Dale Taylor
Original assignee: Greif International Holding BV
Current assignee: Greif International Holding BV
Priority date: 2012-02-17
Filing date: 2013-02-15
Publication date: 2015-01-15
Also published as: US20150028036A1; US9669969B2; WO2013121024A1; WO2013121025A1; US20150034651A1; WO2013121023A1

Abstract

A securing ring for holding a lid or similar closure on a container includes a ring end having a radially outer surface. A latch lever is mounted by one end to the radially outer surface by a pivotable connection. The radially outer surface is recessed to at least partially accommodate the pivotable connection, thereby reducing the radial profile of the ring latching mechanism.

Description

FIELD OF THE INVENTION

This invention concerns a latched securing ring for holding a lid or similar closure on a container, the ring for example being of the kind having an inwardly facing, circumferentially extending groove arranged to trap a rim of the lid/closure and also trap a peripheral flange or similar radial extension(s) provided around an opening in the container. In this way the lid rim and container flange are locked together.

INVENTION BACKGROUND

Where the ring is re-useable, it is typically openable to allow installation over or removal from the flange and rim. Then the ring will usually comprise a circumferential discontinuity which forms a pair of overlappable or opposed ends which are releasably secured together by a latch mechanism. The groove profile will often be tapered, to draw the flange and rim into engagement with each other as the ring is tightened, and optionally to draw the flange and rim into clamping engagement with an interposed sealing gasket. However such clamping and/or sealing functions need not always be present. Optionally, the ring latch mechanism may be provided with an anti-tamper lock pin or similar tamper indicating security seal or tag, to provide some guarantee of the integrity of the container contents. The container and its opening may be of various sizes and shapes, with lids or other closures of a suitable corresponding size and shape. For example the opening and lid may be substantially square, rectangular or other polygonal shape. Typically the lid or closure is round, for fitment to an open-ended cylindrical drum. In the North American market, fibreboard drums with steel end chimes are commonly used together with injection moulded lids. Open-topped blow-moulded plastics drums are also used, again with injection moulded plastics lids. The blow moulded drums predominate in other markets.
Historically the openable securing rings have been made from metal, commonly painted or plated steel. However these are difficult to recycle and are prone to corrosion, or to flaking of the coating. Corrosion or coating particles shed by the ring can contaminate the container contents. There is therefore an increasing use of securing rings made from plastics. U.S. Pat. Nos. 4,194,772, 4,678,216, 5,129,537, 5,713,482, 7,243,962 and US2009/0294449 relate to such plastics securing rings.
To be strong enough to survive normal rough handling of the filled containers, plastics securing rings need to be made with a heavier (thicker) cross-section than a corresponding metal ring. Similarly, the latch mechanism for the openable ring ends tends to be significantly bulkier in a plastics ring compared to a metal ring. This can lead to a number of problems. One group of problems arises when the bulkier latch protrudes radially from the container to a significant degree. This limits the relative orientations in which the containers can be packed closely together side by side during transport or storage. Drums are also often moved short distances by turning them on their side and rolling them, e.g. to move them along the length of a truck trailer during loading and unloading. A highly protruding latch is not only prone to mechanical damage, but will also prevent the drum from rolling in a straight line. Some existing plastics latch designs protrude to an extent which prevents the containers from being rolled along the length of a typical truck trailer without running into, or falling off, the trailer sides.

SUMMARY OF THE INVENTION

The present invention provides a securing ring for holding a lid or similar closure on a container, the securing ring comprising:
a ring end having a radially outer surface;
a latch lever having a latch lever end, and
a pivotable connection by which the latch lever end is mounted to the radially outer surface, the radially outer surface being recessed so as to at least partially accommodate the pivotable connection. Because the pivotable connection is at least partially accommodated in the recessed radially outer surface of the ring end, the overall radial height (radial size) of the lever and ring end assembly is reduced. The ring end and latch lever assembly may similarly form parts of a securing ring latch mechanism of reduced radial dimension.
The pivotable connection may comprise a pivot shaft receivable in a bearing recess, preferably as a snap fit for ease of assembly. The pivot shaft may be mounted to the latch lever end, for example by a centre web and by two end webs, one said end web being disposed respectively on either side of the centre web. This provides a robust mounting which is not significantly weakened by moulding knit lines.
The bearing recess may comprise at least one hook shaped formation upstanding from a depression which forms the recessed radially outer surface of the ring end. In this way, a snap-fit bearing for the pivot shaft is conveniently produced which is readily formed with an optimally low profile.
For strength and compactness, the latch lever may comprise a top wall and a pair of side walls which define a channel within which the ring end may be at least partially received when the lever is in a closed condition.
The ring may comprise a further ring end to which the lever is mounted by a further pivotable connection.
The ring end, further ring end and lever may form at least part of a latch mechanism having a radially inner portion of reduced axial external thickness so as to provide relief for stable stacking of a first container on top of a second container when the securing ring is attached to the second container.
The lever may comprise:
an elongate top wall which, with the lever in a closed position, lies radially outward of said ring end and extends generally circumferentially of the ring, and
a pair of opposed side walls, co-extensive with the top wall and lying axially to either side of said ring end, so as to form, together with the top wall, a channel in which said ring end is at least partially received.
With the lever in the closed position, a radially inner edge of at least one of the lever side walls preferably lies radially outward of the inner diameter of said ring end to define at least part of the radially inner portion of reduced axial external thickness.
The further ring end may comprise an opposed pair of further walls lying axially to either side of the ring and between which the lever is mounted by the further pivotable connection, and,
with the lever in the closed position, a radially inner edge of at least one of the further walls lies at least as far radially outward as the at least one lever side wall radially inner edge, to define at least part of the radially inner portion of reduced axial external thickness.
The securing ring may comprise a main part having a profile which is extended into said further ring end between said further side walls.
The further pivotable connection may comprise a further pivot shaft cantilevered from the further ring end. This provides a tough pivotable connection which may be easily assembled with the lever and which may be readily formed without weaknesses arising from moulding knit lines.
For compactness and ease of assembly, the further ring end may comprise a yoke from which the further pivot shaft is cantilevered.
The further pivot shaft may comprise an enlarged free end. This strengthens the pivot assembly and assists in retaining the further pivot shaft in its bearing by providing a mechanical key.
To further assist in reducing the radial dimension of the ring end and lever assembly, the radially outer surface of said ring end and/or the latch lever top wall may comprise one or more further recesses which accommodate a portion of the enlarged free end.
Some or all of the recess and further recess(es) may be blind-ended. In this way a continuous and, if desired, smooth, outer surface of the ring can be maintained. The continuous surface presents a neat appearance and is hygienic by minimising crevices where dirt and contaminants may accumulate.
The further pivot shaft may be slidable in a slot in one of the side walls of the lever. This eases assembly and can allow the ring to open or expand circumferentially to a greater extent than otherwise possible.
The ring end may comprise a tip having an radially outwardly projecting detent with an engagement surface facing circumferentially rearward of the ring end and the further ring end may comprise a radially inwardly projecting detent with an engagement surface facing circumferentially rearward of the further ring end, the engagement surfaces being mutually engageable for the transfer of hoop stress between the ring end and further ring end. Locating the outwardly projecting detent at the ring end tip reduces the overlap between the interengaged ring end and further ring end and thereby increases the angle through which the lever may be pivoted. This in turn increases the amount by which the ring may be expanded and contracted.
For additional security, the lever and ring end may comprise a snap-fit interlock which is engaged when the lever is in a closed position over the ring end, and which is manually disengaged as the lever is raised from the closed position by pivoting about said pivotable connection.
The snap-fit interlock may be positioned whereby, when the lever is closed, components of the interlock are accommodated between the pivotable connection and the further pivotable connection. This improves the mechanical advantage when manually disengaging the interlock as the lever is raised.
The above and other preferred features and advantages of the invention are further described below with reference to illustrative embodiments of the invention shown in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a first embodiment of a securing ring according to the present invention, but with the latch lever removed so as to show internal features of the latch ring;

FIG. 2 corresponds to FIG. 1, but shows the securing ring in half section, again with the latch lever removed;

FIGS. 3-7 are, respectively, perspective, top plan, underplan, front end and rear end views of the latch lever of the embodiment of FIGS. 1 and 2, shown separated from the remainder of the securing ring;

FIG. 8 is a longitudinal section through the latch lever mechanism of a second embodiment of the invention;

FIG. 8 a is an enlarged view of a portion of FIG. 8;

FIG. 9 is a perspective view of the latch lever mechanism of FIG. 8;

FIG. 10 is a cross-sectional view through a pair of stacked containers and a securing ring latch lever mechanism as shown in FIGS. 8, 8 a and 9, and

FIG. 11 is a scrap view of a portion of FIG. 10.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A first embodiment of the present invention is shown in FIGS. 1-7. The securing ring in the portion not shown in FIG. 1 is circumferentially continuous and of the same profile as the immediately adjacent portions which are shown in FIG. 1. The partially illustrated securing ring 10 comprises a discontinuity 12 which defines a ring end 14 and a further ring end 16. The securing ring 10 comprises a pair of side walls 18, and a top wall 23 having a radially outer surface 22. The securing ring is therefore of generally U-shaped radial cross-sectional profile, providing an inwardly facing circumferential groove 24 adapted to secure a drum lid (not shown) to a drum end chime (not shown).
The radially outer surface 22 of the top wall 23 extends into the securing ring end 14 and is recessed at 26 to partially accommodate a pivot shaft 28 mounted to one end of a latch lever 30 by a centre web 32 and a pair of end webs 34. The pivot shaft 28 is snap-fittable into a pair of bearing recesses 36 defined by a pair of hook shaped formations 38 upstanding from the outer surface recess 26. For clarity and simplicity, only one of the hook shaped formations 38 is shown in the half-sectional view of FIG. 2; the two formations being substantially identical (the securing ring being substantially mirror-symmetrical about its axial centre plane). When the lever 30 is mounted to the ring end 14, each hook shaped formation 38 partially encircles the pivot shaft 28 between the centre web 32 and a respective one of the end webs 34. The pivot shaft 28 and hook shaped formations with their bearing recesses 36 thereby form a pivotable connection by which the lever 30 is snap-fittingly mounted to the radially outer surface 22. This pivotable connection is partially let into the thickness 22 a of the ring top wall by virtue of the recess 26. This reduces the radial height or size of the lever 30 and end 14 assembly when the lever is in its closed position, oriented generally tangential to and covering the ring end 14. The lever 30 comprises a top wall 40 and a pair of side walls 42 which together define a channel-shaped interior space 44 which at least partially receives the ring end 14 when the lever is in the closed position.
In a modification, the recess 26 may extend all the way through the top wall 22 a, to form a window in which the pivot shaft 28 is partially accommodated. However, the pivot shaft preferably does not intrude significantly into the groove 24, so as not to interfere with the securing ring's installation about a container and lid. It is preferred that at least a thin web of top wall material remains at the bottom of the recess 26, to better confine the pivot shaft 28 in the bearing recess 36 and to act a barrier against ingress of contaminants into the groove 24.
The discontinuity 12 defines a further ring end 16, which comprises a yoke 46 having a pair of opposed, generally parallel arms 48. Each arm 48 is a continuation of one of the ring side walls 18 and carries an inwardly extending cantilevered pivot shaft 50. The two pivot shafts 50 are co-axially opposed and each has a button-shaped, enlarged free end 52 (only one such end 52 being visible in FIG. 2). The lever side walls 42 are each provided with a longitudinal through-going slot 54 running into an enlarged entrance aperture 56, as best seen in FIG. 3. At its end opposite to the entrance aperture 56 and closest to the pivot shaft 28, the slot 54 defines a curved interior bearing surface 58. The entrance apertures 56 are large enough to receive the shaft ends 52, whereas the slots 54 are wide enough to receive the root ends of the cantilevered shafts 50 but too narrow to allow the shaft ends 52 to pass through. The yoke arms 48 are spaced apart a distance which will snugly fit the width of the lever 30. They can be resiliently spread apart enough to allow the shaft ends 52 to snap through the entrance apertures 56 in the lever sides 42. The lever 30 may then be slid relative to the yoke 46 so that the root ends of the cantilevered shafts 50 move into the slots 54, trapping the enlarged ends 52 within the lever interior space 44 and providing a mechanically keyed connection with the lever 30. With the lever in its open position, pivoted about the pivotable connection 28/36 to lie generally radially of the ring 10 (or even pivoted through an angle of more than 90 degrees away from its closed position resting against the ring end 14), the cantilever pivot shafts 50 may be slid along the slots 54 towards the entrance apertures 56, to further open the ring 10. As the lever is pivoted about the connection 28/36 towards its closed position, the shafts 50 first move along the slots 54 until they reach the bearing surfaces 58. The cantilever pivot shafts 50 and bearing surfaces 58 then form further pivoted connections about which the lever rotates relative to the yoke as the lever continues to move toward its closed position, drawing the yoke 46 into overlapping engagement with the ring end 14.
To further assist in reducing the radial profile of the overlapping ring ends 14, 16, the radially outer surface 22 of the ring end 14 preferably comprises two further recesses 60 which each accommodate a portion of one of the enlarged free ends 52 of the cantilevered pivot shafts 50.
The lever interior 44 is preferably further provided with a transverse web 64, to which the centre web 32 is also attached. With the lever 30 in its closed position, a forward surface of the web 64, lying closest to the pivot shaft 28, rests against a pair of pegs 66. These pegs are integrally moulded with the ring end 14 to stand up from the top wall radially outer surface 22. Contact between the pegs 66 and the transverse web 64 transmits tensile hoop stress in the ring end 14 into the lever 30 as compressive stress, thereby sharing and partially relieving the stress burden on the pivotable connection 28/36. The transverse web 66, together with further lever interior walls 65 also help to confine and constrain the button-shaped enlarged ends 52 of the further pivot shafts 50, thereby strengthening the pivotable connection 50/58 when the pivot shafts 50 are engaged with the bearing surfaces 58.
Similarly, the hook shaped formations 38 preferably each comprise a hind portion 68 extending towards the tip 70 of the ring end 14. The top wall 23 of the ring 10 extends forwardly between the arms 48 of the yoke 46 to form a web portion 72 which overlies the hook shaped formations 38 when the ring end 14 and further ring end 16 are brought together. A further web portion 74 depends from the web portion 72 and is attached between the web portion 72 and the ring side walls 18/yoke arms 48. The further web portion 74 engages in complementary slots formed in the hind portions 68 of the hook shaped formations 38 when the ring ends 14, 16 are brought together (see FIG. 2). Tensile hoop stress can therefore be transmitted directly between the thus interengaged ring ends 14, 16, relieving the stress burden on the lever mechanism and its pivotable connections 28/36 and 50/58.
A pair of ears 76 is integrally moulded with the ring end 14 so as to protrude radially from the ring top wall 23 into the interior space 44 when the lever 30 is in its closed position. In that position, axially aligned through holes 78 in the ears 76 also align with the slots 54 for reception of a security tag, tamper indicating lock pin, or the like. Thus the lever 30 cannot be moved to its open position without removing or breaking the tag etc.
A second embodiment of the invention is shown in FIGS. 8, 8 a and 9. This embodiment is generally similar to the embodiment described above, but with the following differences.
The section plane of FIG. 8 is shifted away from the transverse centre plane and towards the viewer. A central longitudinal web 31 in the latch lever interior is therefore visible. Components behind this web are not shown or further described, since the mechanism is mirror-symmetrical about the longitudinal centre plane, and therefore there is an identical set of components on either side of the web 31. For brevity, the following description is mainly confined to the visible set of these components only.
Comparing with FIG. 2, in FIGS. 8 and 8 a the further web portion 74 is moved further towards the tip 70 of the ring end 14. For the stress transfer directly between the interengaged ring ends 14, 16, a transverse wall 80 is provided, upstanding radially from the very tip 70 of the ring end 14, for engagement behind the further web portion 74. The hook shaped formations 38 therefore lack the complementary recess shown in FIG. 2, and are correspondingly shifted towards the ring end tip 70. The overlying web 72 is correspondingly shortened compared to the overall length of the yoke arms 48 (see FIG. 9). This allows the lever 30 to pivot through a wide angle (e.g. 150 degrees) about the further pivotable connection 50/58 (not shown in FIGS. 8 and 8 a) from the closed position before the lever top wall 40 hits the edge 73 of the web 72. This is desirable as it allows greater expansion and contraction of the ring 10 on opening and closing the lever 30. The overall radial height of the yoke 46 and lever 30 is further reduced by providing recesses 82 in the underside of the overlying web 72, to accommodate a top part of the hook shaped formations 38. Similarly, as best seen in FIG. 8, the undersurface of the lever top wall 40 is provided with a pair of elongate recesses 62 extending lengthwise of the lever 30. These recesses 62 receive portions of the cantilever shaft 50 enlarged free ends 52, so as to reduce the radial profile of the lever 30 when it rests in the closed position over the ring end 14. At the same time, the elongate recesses 62 allow the shafts 50 and their enlarged ends 52 to still slide along the length of the slots 54. The resultant reduced lever height also further increases the possible lever opening angle. The recesses 62 may extend through the entire thickness of the lever top wall 30 to form windows, but it is preferred to maintain at least a thin web of material across the bottom of each recess (i.e. at the outer skin of the lever 30) as shown, for strength, hygiene and aesthetic reasons.
Adopting the design features shown in FIGS. 1-7 allows an approximate 25% reduction in the radial height of the ring and latch lever when the lever is in the closed position, compared to prior art designs as shown for example in US published patent application no. US2009/0294449. Reducing the pivot shaft diameters from 0.300 inches (7.62 mm) as used in FIGS. 1-7 above, to 0.250 inches (6.35 mm), together with the further design features in
FIGS. 8, 8 a and 9, allows the radial projection of the closed latch lever above the ring (and similarly the radial projection of the further ring end 16) to be reduced to only 0.375 inches (9.53 mm). This is comparable with steel securing rings and latch mechanisms in current use.
Moving the hook shaped formations closer to the tip 70 of the ring end 14 as in FIGS. 8, 8 a and 9, also makes available extra space between the pivotable connections 28/36 and 50/58. As shown in FIGS. 8 and 8 a, this extra space can be used to accommodate a snap-fit interlock which holds the lever in its closed position until manually unsnapped as the lever is raised. The interlock as shown comprises a post 82 moulded onto the underside of the lever top wall 40 and having a cruciform slotted, bulbous tip 84. When the lever is moved to the closed position, the tip 84 is snap-fittingly engageable beneath a radially inwardly projecting lip 86 formed at the top of a wall 88. The wall 88 is moulded onto the ring end 14 upper surface 22 and partially surrounds the post 82 when the lever 30 is in the closed position.
The extra distance between the pivotable connections 28/36 and 50/58, due to the ring curvature, also maintains the overcentre action of the lever mechanism, despite the decreased lever radial projection. The lever mechanism will therefore remain stably closed (i.e. hold the ring ends together in a circumferentially contracted state) even without the assistance of the snap fit interlock features 82/88.
Referring to FIGS. 9-11, a radially inner portion of the releasable fastening or latch mechanism formed by the ring ends 14, 16 and latch lever 30 has a circumferentially extending recess 130, so that the axial external thickness of the radially inner portion is reduced. In this embodiment of the invention, the latch mechanism is again of all plastics construction. To provide the circumferentially extending recess 130, a side wall 48 of the channel shaped further ring end 16 has a free edge 24 a which terminates radially outwardly of a free edge 26 a of the latch lever 30 side wall 42. Similarly the lever side wall 42 free edge 26 a terminates radially outwardly of (i.e. at a larger radius from the centre of the ring 10 than) the free edge 28 a of the channel-shaped ring end 14 side wall 18. The further ring end 16 side wall 48 thus partly overlies the latch lever side wall 42 which in turn partly overlies the ring end 14 side wall 18 when the latch lever 30 is in its closed, circumferentially extending position. In this way, all three channel free edges 24 a, 26 a, 28 a in the latch mechanism form the boundary to the recess 130 and terminate just short of an upper container 112 bottom end chime 120 when that container is stacked on top of a container 114 to which the ring 10 has been fitted. At the region where the bottom end chime 120 crosses the ring latch mechanism, the bottom end chime is therefore received within the recess 130. This contrasts with arrangements of the prior art, where the free edges of the latch components 14, 16, 30 all terminate at substantially the same ring radius and can therefore block and interfere with the desired positioning of the upper container bottom end chime, when endeavouring to stack one container on top of another. Using a securing ring in accordance with FIGS. 8 and 9, the bottom of the upper container 112 is instead able to rest flat in face-to-face contact with an upstanding central part 118 of a lid 116 of the lower container 114. The upper container 112 is therefore stably supported upright with loads distributed over a wide area of its base and over a wide area of the supporting lower container lid, without imposing any additional load on the ring 10 latch mechanism. The latch lever and ring end arrangement shown in FIGS. 1-7 is preferably similar, with the lower edges 24 a of the yoke 46 arms 48 (lower edges 24 a of the ring side wall continuations at the ring further end 16) lying at a larger radius from the centre of the ring 10 than the lower edges 28 a of the ring end 14. One or both of the lower edges 26 a of the latch lever 30 when it is assembled with the ring ends 14, 16 and is in its circumferentially extending, closed position, preferably lie(s) at a radius from the centre of the ring 10 which is greater than the radius of the edges 28 a, but less than or equal to the radius of the edges 26 a. In this way, a radially inner portion of the latch mechanism of reduced axial external thickness is again provided.

Claims

1. A securing ring for holding a lid or other closure on a container, the securing ring comprising:

a ring end having a radially outer surface;

a further ring end;

a latch lever having a latch lever end; and

a pivotable connection by which the latch lever end is mounted to the radially outer surface,

wherein the radially outer surface is recessed to at least partially accommodate the pivotable connection, and

wherein the latch lever comprises a top wall and a pair of side walls which define a channel within which the ring end is at least partially received when the latch lever is in a closed position.

2. The securing ring of claim 1, wherein the pivotable connection comprises a pivot shaft receivable in a bearing recess.

3. The securing ring of claim 2, wherein the pivot shaft is receivable in the bearing recess as a snap fit.

4. The securing ring of claim 2, wherein the pivot shaft is mounted to the latch lever end by a centre web and by two end webs, each of said end webs being disposed respectively on either side of the centre web.

5. The securing ring of claim 2, wherein the bearing recess comprises at least one hook shaped formation upstanding from the recessed radially outer surface of the ring end.

6. The securing ring of claim 1, wherein the latch lever is mounted to the further ring end by a further pivotable connection.

7. The securing ring of claim 6, wherein the ring end, the further ring end and the latch lever form at least part of a latch mechanism having a radially inner portion of reduced axial external thickness relative to a radially outer portion of the latch mechanism.

8. The securing ring of claim 7, wherein the latch lever comprises:

an elongate top wall which, when the latch lever in the closed position, lies radially outward of said ring end and extends generally circumferentially of the securing ring, and

a pair of opposed side walls, co-extensive with the top wall and lying axially to either side of said ring end to form, together with the top wall, a channel in which said ring end is at least partially received.

9. The securing ring of claim 8, wherein, when the latch lever in the closed position, a radially inner edge of at least one of the latch lever side walls lies radially outward of an inner diameter of said ring end to define at least part of the radially inner portion of reduced axial external thickness.

10. The securing ring of claim 9, wherein:

the further ring end comprises an opposed pair of further walls lying axially to either side of the securing ring and between which the latch lever is mounted by the further pivotable connection, and

when the latch lever in the closed position, a radially inner edge of at least one of the further walls lies at least as far radially outward as the at least one latch lever side wall radially inner edge, to define at least part of the radially inner portion of reduced axial external thickness.

11. The securing ring of claim 10, wherein the securing ring comprises a profile which is extended into the further ring end between said further side walls.

12. The securing ring of claim 6, wherein the further pivotable connection comprises a further pivot shaft having an end by which the further pivot shaft is secured to project freely from the further ring end.

13. The securing ring of claim 12, wherein the further ring end comprises a yoke to which the further pivot shaft is secured.

14. The securing ring of claim 12, wherein the further pivot shaft comprises an enlarged free end.

15. The securing ring of claim 14, wherein the radially outer surface of said ring end or the latch lever top wall comprises one or more further recesses which accommodate a portion of the enlarged free end.

16. The securing ring of claim 15, wherein the recessed ring radially outer surface comprises a blind ended recess, or one or more of the further recesses are blind-ended.

17. The securing ring of claim 12, wherein the latch lever comprises a side wall, and the further pivot shaft is slidable in a slot in the latch lever side wall.

18. The securing ring of claim 1, wherein:

the ring end comprises a tip having a radially outwardly projecting detent with an engagement surface facing circumferentially rearward of the ring end, and

the further ring end comprises a radially inwardly projecting detent with an engagement surface facing circumferentially rearward of the further ring end,

the engagement surfaces of the ring end and the further ring end are mutually engageable for the transfer of hoop stress between the ring end and the further ring end.

19. The securing ring of claim 1, wherein:

the latch lever and ring end comprise a snap-fit interlock which is engaged when the latch lever is in the closed position over the ring end, and

the snap-fit interlock is disengaged by raising the latch lever from the closed position by pivoting the latch lever about said pivotable connection.

20. The securing ring of claim 19, wherein:

the latch lever is mounted to the further ring end by a further pivotable connection, and

the snap-fit interlock is positioned such that, when the latch lever is in the closed position, components of the snap-fit interlock are accommodated between the pivotable connection and the further pivotable connection.

21. A securing ring for holding a lid or other closure on a container, the securing ring comprising:

a ring end;

a further ring end;

a latch lever having a latch lever end; and

a pivotable connection by which the latch lever end is mounted to the ring end,

wherein the latch lever and ring end comprise a snap-fit interlock which is engaged when the latch lever is in a closed position over the ring end, and

wherein the snap-fit interlock is disengaged by raising the latch lever from the closed position by pivoting the latch lever about said pivotable connection.

22. The securing ring of claim 21, wherein:

23. The securing ring of claim 21, wherein:

the latch lever comprises a top wall having an underside,. and

the snap-fit interlock comprises a post extending from the underside of the top wall and a projecting lip formed at the top of a wall upstanding from a radially outer surface of the ring end.

24. The securing ring of claim 1, wherein the securing ring is made of a plastic.