Gripping and turning device for rotatable closures of containers

Abstract

A gripping and turning device 10 for rotatable closures comprises a shroud 11 with a plurality of graduated receiving and gripping regions 13 each for receiving and gripping a circular closure 30 of different diameters, and manually actuable mean, for example two handles 19, for deforming the shroud and applying a turning force to the gripped closure. The shroud may comprise a frusto-conical body, and the casing and the insert may be of different materials, the insert may be of resiliently compressible material, such as a thermoplastic elastomer. The device may aid elderly, arthritic, those who have recently undergone surgery or those with weak muscles or joints and may aid with the force required to replace the closure in order to make an airtight seal.

Description

The present invention relates to a gripping and turning device for rotatable closures of containers, especially a lid and cap remover and applicator, and has particular reference to a device compatible with closures of different diameters. Screw-type lid and cap closures for glass jars and bottles are often difficult to remove because of the elevated frictional force holding them in place. This is a consequence of the torque generated when they are rotationally applied by industrial automation machines and may on occasion be accentuated by an air pressure differential between the interior of the container and the exterior environment induced by cooling of food content after the closure has been applied. This results in depressurisation and drawing the closure into tighter frictional contact with the glass than would be the case without the pressure differential. The force required to rotate the closure in order to remove it can be greater than that achievable by the unassisted human hand, especially in the case of the elderly and the arthritic, those who have recently undergone surgery or those with weak muscles or joints. Equally, the force required to replace the closure in order to make an airtight seal may be greater than that achievable by hand without assistance. Many existing opener-type devices are intended to provide a low-cost and easy-to-use mechanical means of achieving removal of closures from jars and bottles. These openers do not, however, effectively address all the problems associated with simplicity of operation, provision for removing and replacing closures of different size, and low cost of manufacture. In one approach as disclosed in US Patent No. 4,179,954 (Whalen), two symmetrical gripping members are each provided with a plurality of arcuate notches of minimum, intermediate and maximum radii arranged in order from smallest to largest. A resilient joining or hinging member connecting the gripping members together at hinged ends thereof allows the gripping members to be urged towards one another so that a selected pair of the notches can grasp a closure at its circumference. The notches are preferably lined with rubber to improve grip quality. Handles extend from non-hinged ends of the gripping members to assist movement of the gripping members towards one another to grasp a closure. A generally similar approach disclosed by US Patent No. 7,069,815 B1 (Siu Kwan Yu) provides a pair of symmetrical gripping wings pivotably connected at a junction so as to allow pivotation to bring a selectable one of several differently sized pairs of arcuate gripping regions of the wings into contact with the circumference of a closure. The junction between the two wings takes the form of a narrowing of the structure relative to the wings and when manufactured from a suitable deformable polymer the joining section enables local deformation, this arrangement being known in the field of plastics injection-moulding as a live hinge. The device disclosed by Yu may be formed by injection-moulding as an integral part from a suitable resilient and stiff polymer such as polypropylene or acrylonitrile-butadiene-styrene in distinction to Whalen, where the device is created from an assemblage of parts. However, a single-part approach requires fewer process steps and lends itself to lower cost of manufacture. The gripping regions are provided with a thin layer of thermoplastic elastomer to promote deformation when brought into frictional and compressive contact with a closure, thereby enhancing frictional grip. While the devices disclosed by Whalen and Yu are designed for gripping closures in a range of sizes, closures with a diameter in excess of the largest gripping region and inferior to the smallest gripping region cannot be gripped and closures of intermediate size require two-handed manipulation of the device to adjust the gripping wings by pivotation around the hinge junction to increase the separation distance between the wings in order to bring the gripping regions into contact with sections of a side wall of the closure. Two-handed manipulation requires some skill, strength and co-ordination on the part of the user and may be challenging for those with an arthritic or similar degenerative condition or those with small hands, weak muscles or weak joints. Moreover, two-handed manipulation precludes holding the jar or bottle with the closure during the time that the device is being adjusted to fit the closure, with the risk that the jar or bottle may slide uncontrollably when it is contacted by the device, with the further risk of complicating the gripping process and damaging or breaking the jar or bottle. In the case of a closure having a diameter between two adjacent pairs of gripping regions, the surface area available for gripping is considerably less than in the case of a closure with a diameter corresponding with the diameter of a pair of gripping regions. It can be assumed that gripping of such a closure will be inferior to that of a closure with a diameter equating with a close fit. While cost of manufacture is addressed by Yu through the creation of integral gripping wings and pivot junction by injection-moulding, as distinct from Whalen where multiple parts are required, the provision of a thin layer of elastomeric material on the gripping regions, which is achieved by a multi-step process known as co-moulding, requires the manufacture of large numbers of the product to reach a sufficiently low price-point appropriate to the market. Co-moulding is required in this instance, as the gripping layer, which is relatively shallow in depth and exposed along its length, will tend to peel away from the support structure if attached by an adhesive or by mechanical retention. A tool for gripping multiple sizes of closure is disclosed in US Patent No. 2779224 A (Lee Coggburn and Harley) and has the form of pliers consisting of two gripping arms pivotably connected by means of a pin passing through slots in the arms. Each slot has arcuate notches along one edge and a free end of each arm has a concave gripping portion for gripping a screw-type closure. Adjustment to enable gripping of closures in a range of sizes is achieved by pushing on one handle and pulling on the other to cause the pin to pass along the slots and, upon drawing the arms together, to locate in an arcuate notch thereby creating a selectable point of pivotation. Two-handed manipulation is required to adjust the pliers and it is possible that the concave gripping portions, which are formed from metal and are provided with serrations, may damage and deform the closure. The provision of a single radius of curvature at the concave gripping portion creates a mismatch with the exterior circumference of a closure, thereby reducing contact surface area and undesirably creating localised areas of elevated gripping force, which may increase the risk of damage to the closure. A generally conical gripping device as disclosed in US Patent No. 4766781 A (Grise and Adams) comprises a stiff outer cone and an insert of elastomeric material loosely conforming to the cone. When brought into contact with a closure the insert is stretched and distorted to increase the area of frictional contact. While the conical form allows more than one closure size to be accommodated, no provision is made for assisting the turning force achievable by a human hand, for example by means of a handle or handles. Consequently, only closures requiring moderate turning force may be able to be gripped and removed. A similar conical device as disclosed in US Patent No. 358937 (Armstrong) comprises a single part formed from an elastic material and has no means of gearing the force achievable by the human hand. US Patent No. 20152468021 A1 (Heitz) discloses a device for removing closures with multiple receiving and gripping portions to enable containers in a range of sizes to be opened. A housing attached to a stationary object such as the underside of a kitchen cupboard is provided with a plurality of circular recesses, within each of which is arranged a series of coaxial grips with gradually smaller diameters dimensioned to receive closures of different sizes, the grips being made of rubber. The grip most closely corresponding with the diameter of the closure envelops it. An unspecified means of electromechanical actuation causes the grip to close around the closure. The user then twists the container itself to remove the closure. While this device accommodates more than one lid closure size, there is no gearing to assist the user and accordingly only closures requiring moderate turning force may be able to be gripped and removed. Electromechanical actuation is required to complete the gripping process, which introduces cost and complexity. Removal of a closure requires the user to hold and twist the container, which requires a degree of co-ordination and physical strength. In some instances the moment of release of the closure may be difficult to control, as the weight of the container and its content may transfer unpredictably from the device to the user. It is therefore the principal object of the present invention to provide a gripping and turning device, in particular for rotatable closures of containers, with a capability of co-operating with closures of different diameter to enable removal and refitting of the closures from and to containers. A further object of the invention is provision of such a gripping and turning device which addresses at least some of the mentioned issues affecting the discussed prior art devices, such as ease of use by users including handicapped users, security of gripping of closure circumferences, manufacturing cost and manufacturing simplicity. Other objects and advantages of the invention will be apparent from the following description. According to the present invention there is provided a gripping and turning device for rotatable closures of containers, comprising a shroud provided in its interior with a plurality of receiving and gripping regions each for receiving and gripping a respective one of a corresponding plurality of rotatable circular closures, which are of respectively different diameters, at the circumference thereof, the receiving and gripping regions being graduated to reduce in size with respect to closure diameter in a direction away from an entry end of the shroud and the shroud being positionable by way of its entry end over a closure for reception of the closure in that one of the receiving and gripping regions providing a tightest fit with the circumference of the closure and being resiliently deformable to produce pressurable interengagement of that region and the circumference of the received closure thereby to frictionally grip the closure, and further comprising manually actuable means for deforming the shroud and for use in applying a turning force to the deformed shroud together with a gripped closure. A gripping and turning device embodying the invention and having such a configuration is particularly simple to apply to a closure of a container by pushing the shroud onto the closure until the closure is received in the receiving and gripping region offering the tightest fit with the closure circumference. The tightest fit may be represented by a more or less exact diameter match, a slight tolerance to be taken up by subsequent deformation of the shroud in the sense of compression, or even an undersize of the region requiring deformation of the shroud in the sense of expansion in order to achieve reception and gripping. Once the closure is received the manually actuable means can be actuated to deform the shroud to create a tight frictional grip of the closure and then turned to enable rotation of the closure on the container and thus removal. Fitting of the closure to the container involves the same procedure, in which case the free closure can be inserted into the shroud or alternatively the closure can initially be loosely seated on the container and then the shroud pushed onto the closure. In the case of refitting after removal the removed closure remains held by frictional force in the relevant receiving and gripping region of the shroud and can be refitted by being loosely seated on the container and then rotated by the device after the shroud has been deformed by the device to create a tight frictional grip of the closure. Release of the closure from the receiving and gripping region is achieved by finger pressure on the closure in a direction towards the entry end of the shroud. The provision of a range of receiving and gripping regions graduated to reduce in size with respect to closure diameter in a direction away from the shroud entry end, in effect a substantially coaxial stack of regions reducing in size in steps, makes it possible to accommodate typical sizes of jar or bottle lid diameters, particularly if the sizes of the receiving and gripping regions are selected to correspond with typical or most common lid sizes. The number of regions can be a compromise between maximising the range without detracting from the compactness and wieldability of the devices, about seven such regions being an appropriate number in that respect. In a preferred construction of the device, in particular the shroud, each of the receiving and gripping regions is formed by a surface or a plurality of discrete surfaces extending on the arc of a major sector of a circle. In this configuration of the regions the surface or surfaces of each region will embrace more than half the circumference of a received closure, thus ensuring secure reception and gripping of the closure. In addition, the arcuate form of the or each surface will generally conform with the circumference of a received closure so as to maximise grip area. In that connection it is advantageous if the sector is at least 300 and at most 330 degrees, for preference substantially 315 degrees. A sector of such a size allows gripping of at least five-sixths of the circumference of a closure and thus provides a particularly firm hold of the closure with little or no risk of slipping once the shroud has been suitably deformed. For preference, the shroud comprises a substantially frusto-conical body and the entry end of the shroud is at the wider end of the body. Such a tapered body shape generally mirrors the taper resulting from the stepped configuration of the stacked receiving and gripping regions so that the shroud can be of relatively thin-walled construction with economic use of material. In an advantageous embodiment the body comprises a casing and an insert fixed therein, the gripping regions being formed at the insert. This two-part construction of the shroud facilitates manufacture through the possibility of use of, for example, two simplified injection-moulding tools each adapted to the requirements of the associated features, in particular a casing deformable by the manually actuable means and a conjunctively deformable insert furnished with the gripping and receiving regions. However, a principal advantage is that the separately moulded casing and insert can be made of different materials so that materials optimised with respect to properties most appropriate to the associated features can be selected. In that case the casing can be, for example, a hard, wear-resistant material with a limited capability of resilient deformation, whereas the insert can be a resiliently compressible material, in particular a material which is softer than that of the casing and which is more readily capable of yielding to assist reception of closures in the receiving and gripping regions and to more securely frictionally grip the circumferences of received closures. The frusto-conical body is preferably formed with a dividing gap extending between the wider and narrower ends thereof and reducible in width under deformation of the shroud. This allows the body to be easily squeezed to tightly grip a closure, in particular by bending of the body with minimal resistance due to the gap. With advantage, the gap occupies a sector of up to 60 degrees, preferably substantially 45 degrees, of the frusto-conical body. A gap of that size means that a closure can be received and gripped over 300 degrees or more of its circumference, which ensures firm frictional interengagement of the body and a closure. For preference, the gripping and receiving regions are each adjoined by a shoulder for bearing on a circular end face of a closure received and gripped by the respective region. Such a shoulder functions as a stop to limit insertion of a closure into the shroud and provides a defined seat for the closure, which enhances the stability of the device particularly when applied to a closure while fitted to a container. In a preferred embodiment of the device, the manually actuable means comprising two handles projecting laterally from the shroud, the handles being spaced from one another in an undeformed state of the shroud and being movable towards one another to exert a deforming force on the shroud. The handles thus act as levers offering substantial mechanical advantage to a user applying force to deform the shroud. If the shroud has the form of a frusto-conical body with a dividing gap, the handles should be positioned on either side of the gap. The handles in that case can be relatively close together in the undeformed state of the shroud, so that the handles can be easily encompassed by the hand of a user. A preferred embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a schematic perspective view of a gripping and turning device embodying the present invention; Fig. 2 is a schematic sectional elevation of part of the device, showing an undeformed state of the shroud of the device; Fig. 3 is an inverted plan view of the part of the device shown in Fig. 2; Fig. 4 is a view similar to Fig. 2, but showing a deformed state of the shroud with gripping of a received lid of a container; and Fig. 5 is a plan view of the part of the device shown in Fig. 4, but without the lid. Referring now to the drawings there is shown a gripping and turning device 10 for rotatable closures of containers, especially screw lids of jars. The device 10 is intended particularly for use in removing lids, which for various reasons as mentioned in the introduction can be difficult to loosen, but can equally well be used for fitting or re-fitting lids. The device 10 comprises, as its principal functional component, a shroud 11 which has the form of a frusto-conical body. The shroud is resiliently deformable, particularly with respect to the size of its circumference, and in the preferred embodiment is injection-moulded from synthetic materials of suitable selected resilience and hardness as indicated further below. The wider end of the frusto-conical body represents an entry end 12 of the shroud, the interior of which has a number - here seven - of gripping and receiving regions 13 each for receiving and gripping a respective one of a corresponding number of rotatable circular closures, in particular screw or bayonet lids, of containers. Each region 13 has the form of a part-cylindrical surface 14 approximately concentric with a cone axis 15 of the frusto-conical body of the shroud 11. The surfaces 14 are graduated or stepped to reduce in diameter in a direction away from the entry end 12 of the shroud and are separated by similarly graduated part-annular planar surfaces 16 also approximately concentric with the cone axis 15, the planar surfaces 16 lying in planes perpendicular to that axis. Adjacent surfaces 14 and 16 are connected at an inner circumference of the respective surface 16 by way of an intermediate chamfer 17 or radius. In addition to reducing in diameter, successive surfaces 14 also reduce in depth, that is to say cylinder length, in the direction away from the shroud entry end 12. The graduated part-cylindrical surfaces 14 are configured to each grip the circumference of a container lid of a respectively corresponding or approximately corresponding diameter. The surface diameters are selected to approximate or to be slightly less than (such as by 2.5 to 5%) typical lid diameters of jars or similar containers, for example - in descending order - 85, 73, 69 / 66, 60, 56, 50 and 45 millimetres. Each of the part-annular planar surfaces 16 is configured to form a shoulder for bearing on a circular end face of a respectively associated lid, thus a lid able to be gripped at its circumference by the surface 14 having a diameter the same as or similar to the maximum diameter of that surface 16. The graduated depths of the surfaces 14 reflect the usually reducing depths of lids with reducing diameters, i.e. the smaller the lid diameter the smaller the lid depth will usually be. By reducing the depths of the surfaces 14, the height of the shroud is limited, thus reducing the proportion of a smaller container that is enclosed by the shroud and increasing the proportion that remains exposed and can be held during removal or fitting of the lid. The shroud 11 is expediently of two-part construction, namely a frusto-conical casing 11a and a frusto-conical insert 11b captively and fixedly retained in the casing, such as by a press fit in a flanged socket or cage of the casing and / or by an adhesive or by comoulding. The gripping and receiving regions 13 of the shroud, thus the surfaces 14 and 16 with intermediate chamfers 17, are formed on the insert. The two-part construction simplifies injection-moulding of the shroud 11 and allows use of different materials for the casing 11a and insert 11b, in particular materials with properties optimised with respect to the requirements of deformability of the casing for the purpose of clamping around a lid as explained further below and deformability of the insert, more specifically the surfaces 14 and 16, when engaging the lid. In that connection, the insert 11b can be of a slightly more yielding material by comparison with that of the casing 11a. Thus, for example, the casing 11a can be moulded from a resilient, but stiff polymer such as acrylonitrile-butadiene-styrene and the insert 11b from a more compliant and deformable polymer such as thermoplastic elastomer with a hardness value of 60 to 70 Shore A. The frusto-conical body of the shroud 11, that is to say in the illustrated embodiment both the casing 11a and the insert 11b, is formed with a dividing gap 18 extending the full length between the wider and narrower ends of the body. The deformability of the shroud 11 is such that the gap 18 can be narrowed by an applied compressive force to compress the shroud, thus reduce its diameter, and produce pressurable interengagement of a selected one of the receiving and gripping regions 13, in particular the part-cylindrical surface 14 of the selected region, with the circumference of a lid received within that surface 14. Release of the applied force allows restoration of the shroud 11 to its original shape. Conversely, the gap can be widened by an applied expanding force to enlarge the shroud, thus increase the shroud diameter, and thereby increase the diameter of the part-cylindrical surface 14 of the selected region 13 to allow a lid to be snugly received - free of play - by its circumference within the surface 14. In order to promote deformability of, in particular, the casing 11a this can be provided with a thinning of its wall in a region diametrically opposite the gap 18. The compressive or expanding force can be applied to the shroud by way of two handles 19 which are formed integrally with and project laterally from the shroud casing 11a with a divergent splay of about 45 degrees and which are positioned on either side of the dividing gap 18. The handles 19 are spaced from one another in the undeformed state of the shroud 11 and are movable towards one another to exert a deforming force on the shroud 11 for compression thereof or, conversely, apart to exert a deforming force in an opposite direction, thus for expansion of the shroud. The minimum spacing of the handles 19, which are additionally curved to splay further apart at their free end regions, is such that although they can be brought into contact with one another in the absence of a received lid, when a lid is received in a selected receiving and gripping region 13 and pressurably engaged at its circumference the handles will still be separated by a substantial proportion of the original minimum spacing. As will be self-evident, the handles 19 also conjunctively function as a lever to apply a torque or turning force to a received and gripped lid in order to remove the lid from or fit the lid to a container, generally an action of unscrewing the lid from or screwing the lid onto a corresponding thread formed on the container. The handles 19 can be provided at sides remote from the separating spacing with shallow depressions or indentations to reduce the risk of slipping when held in the hand of a user and are of a length sufficient to provide an effective lever action without unduly detracting from compactness of the device. The dividing gap 18 occupies a sector of up to about 60 degrees of the frusto-conical body of the shroud 11, preferably about 45 degrees. The receiving and gripping regions 13 of the shroud preferably each extend continuously around the interior of the shroud and accordingly occupy a sector of at least about 300 degrees of the body, preferably about 315 degrees. The regions 13, that is to say the surfaces 14 and 16, can alternatively be discontinuous within the occupying sector, for example, interrupted (not shown) once or several times; interruption may assist the deformability of the insert 11b without significant detraction from the available area of the surfaces 14 for effectively gripping lid circumferences. Similarly, the casing 11a can be formed, particularly at end flanges 20 bounding the socket or cage receiving the insert 11b, with notches or other interruptions to assist the deformability of the casing. Interruptions 21 are shown in the flange 20 at the narrower end of the shroud 11. In a refinement, the part-cylindrical surfaces 14 are curved in sectorial regions, which are intermediate a region containing the dividing gap 18 and a region opposite thereto, about an axis slightly offset relative to the axis 15 in a radially outward direction of the shroud 11. The regions associated with the offset axis will, under deformation of the shroud to grip a closure, bend in such a way as to more closely conform with the circumference of the closure in those regions and thereby provide more intimate contact with the circumference when gripped. Use of the device 10 to grip a lid 30 (Fig. 4) for removal from or fitting to a container 31, such as a glass jar, is largely self-evident from the foregoing description of the preferred embodiment and accompanying drawing figures. The lids 30 and 31 have complementary screw threads which frequently are so tightly locked together by friction when the lid is fitted that the friction cannot be readily overcome by a user due to the limited gripping area afforded by the lid circumference and limits on the strength of the user. Conversely, for the same reasons it may be equally difficult to tightly fit or refit the lid to the container. In a first step, in use of the device, the lid 30 is inserted into the shroud 11 via the wider entry end 12 of its frusto-conical body and pushed into the interior of the insert 11b until the circumference of the lid engages, with least play, into the part-cylindrical surface 14 having a diameter most closely matching that of the lid, thus offering a tightest fit with the circumference of the lid. The shroud 11 can, if desired or necessary, be expanded by way of the handles 19 or by way of force exerted by insertion of an oversize lid so that the lid can engage in a selected surface 14 which, in the unexpanded state of the shroud, has a diameter slightly smaller than that of the lid. When the lid 30 is thus engaged, the associated surface 16 of the insert, i.e. the surface 16 having the same maximum diameter as the diameter of the selected surface 14, can bear against the circular end face of the lid to ensure stable seating of the shroud 11 on the lid. The chamfers 17 themselves ensure smooth passage of an inserted lid 30 into a selected surface 14 of the receiving and gripping regions 13. In a second step, when the lid is received in the selected surface 14 the handles 19 are moved towards one another, thus squeezed together, to deform the shroud 11 in the sense of compression of the casing 11a and insert 11b so that the lid circumference is tightly frictionally gripped by the surface 14 around the full sectorial angle of that surface, thus 315 degrees in the described embodiment. In that connection the slightly softer material of the insert 11b (by comparison with the material of the casing 11a) may yield under the applied pressure to assist creation of a firm frictional grip. In a third step, which is consecutive to the second step, but may follow without interruption, the handles 19 while remaining squeezed together to maintain the grip of the lid circumference are turned in anticlockwise direction relative to the container 31 for lid removal or in clockwise direction for lid fitting - such directions being usual for screw threads or bayonet couplings - while the container is manually restrained from turning with the lid. The leverage afforded by the handles 19 in conjunction with the tight frictional grip of the lid by the shroud 11 allows lid removal and fitting with only a relatively small amount of exertion on the part of the user, normally an amount manageable even by a user with compromised strength or grip capabilities. In a fourth step the handles 19 are released or, if necessary, moved slightly apart to free the lid 30 from the device 10, the lid thus being removed from or refitted to the container 31 as required. A device 10 embodying the invention provides a means of more easily removing closures from and fitting closures to containers, particularly screw lids of glass jars, and achieves this purpose in a relatively economic construction consisting of just two parts or optionally just a single part.

Claims

1. A gripping and turning device for rotatable closures of containers, comprisinga shroud provided in its interior with a plurality of receiving and gripping regions each for receiving and gripping a respective one of a corresponding plurality of rotatable circular closures, which are of respectively different diameters, at the circumference thereof,- the receiving and gripping regions being graduated to reduce in size with respect to closure diameter in a direction away from an entry end of the shroud and- the shroud being positionable by way of its entry end over a closure for reception of the closure in that one of the receiving and gripping regions providing a tightest fit with the circumference of the closure and being resiliently deformable to produce pressurable interengagement of that region and the circumference of the received closure thereby to frictionally grip the closure,and manually actuable means for deforming the shroud and for use in applying a turning force to the deformed shroud together with a gripped closure.

2. A device according to claim 1, wherein each of the receiving and gripping regions is formed by a surface or a plurality of discrete surfaces extending on the arc of a major sector of a circle.

3. A device according to claim 2, wherein the sector is at least 300 and at most 330 degrees.

4. A device according to claim 3, wherein the sector is substantially 315 degrees.

5. A device according to any one of the preceding claims, wherein the shroudcomprises a substantially frusto-conical body and the entry end of the shroud is at the wider end of the body.

6. A device according to claim 5, wherein the body comprises a casing and an insert fixed therein, the gripping regions being formed at the insert.

7. A device according to claim 6, wherein the casing and the insert are of different materials.

8. A device according to claim 6 or claim 7, wherein the insert is of resiliently compressible material.

9. A device according to any one of the claims 5 to 8, wherein the frusto-conical body is formed with a dividing gap extending between the wider and narrower ends thereof and reducible in width under deformation of the shroud.

10. A device according to claim 9, wherein the gap occupies a sector of up to 60 degrees of the frusto-conical body.

11. A device according to claim 10, wherein the sector is substantially 45 degrees.

12. A device according to any one of the preceding claims, wherein the gripping andreceiving regions are each adjoined by a shoulder for bearing on a circular end face of a closure received and gripped by the respective region.

13. A device according to any one of the preceding claims, the manually actuable means comprising two handles projecting laterally from the shroud, the handles being spaced from one another in an undeformed state of the shroud and being movable towards one another to exert a deforming force on the shroud.

14. A device according to claim 13 when appended to any one of claims 9 to 12, wherein the handles are positioned on either side of the gap.

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