GB2576716A - E-cigarette child proofing apparatus - Google Patents

Abstract

The apparatus provides an adapter (17) with a ring formation (18) to be attachable to a spigot (6) providing the threaded connector for a battery pack (1). The battery pack is to be connected to a clearomiser (2) in an E-cigarette whereby the adapter can be irrotatably secured into the E-cigarette by the resulting clamping action. The adapter (17) provides the first part of a child resistant securing mechanism. The second part of a child resistant securing mechanism forms part of a cover (21) whereby the cover can be easily secured to envelop the clearomiser (2) but will resist tampering by a child. The cover can be readily removed to facilitate inhalation from the clearomiser.

Description

CHILD PROOFING AN ELECTRONIC CIGARETTE

Technical Field

The European Tobacco Products Directive (EUTPD) (2014/40/EU requires that electronic cigarettes (e-cigarettes) shall be required to have child resistant features which prevent children from accessing the liquid when the e-cigarette is not being used. For guidance as to the meaning of child resistant the reader may reference BS EN ISO 8317:2015 which specifies performance requirements and test methods for reclosable packages designated as resistant to opening by children. Generally closures meeting the requirements require two or more coordinated movements of parts of the closure to open the closure by separating parts of the closure.

Background Art

As a result of the referenced directive bottles that contain liquid now come with child resistant features, however once the liquid is transferred from the child resistant bottle to the e-cigarette no such protection is provided.

The clearomiser is sometimes known by other names including but not limited to a tank, atomiser, cartomizer, rebuildable atomizer (RBA), rebuildable dripping atomiser (RDA), rebuildable tank atomiser (RTA).. The battery pack comprises a housing adapted to enclose a battery. The battery is commonly a rechargeable battery of conventional chemistry and dimensions. The battery pack will include a charging port, usually a micro-USB port, possibly some form of display, usually LED to indicate the current charge state of the battery a connector to operably connect the battery pack to the clearomiser. The connector is commonly a spigot bearing an external screw thread or a bayonet fitting, however a simple compression (press fit) fitting may also be used. The [0004] [0005] [0006] connector will also include electrical connections to electrically connect the battery to the clearomiser and a manually operable power button.

The clearomiser consists of a clearomiser connector socket to receive the connector spigot from the battery pack. The connector is adapted to seal a liquid containment chamber provided in the clearomiser housing by means of a bung press fitted into a socket of the housing . The connector is readily removable to allow the chamber to be charged with a liquid. A heating element is provided and contacts one or more wicks which depend into the chamber to draw the liquid to the heating element. To facilitate inhalation passages are provided into a mouthpiece from the heating element. The Electrical connections in the socket communicate with the heating element. In use the user actuates the power button causing the liquid soaked heater/wick assembly to heat up sufficiently to vaporise the liquid which vapour is then entrained in air and can be inhaled by mouth.

If the e-cigarette is insecurely put down by its keeper children may access the e-cigarette and copy the adult’s use of the e-cigarette inhaling the vapour. The child may simply suck on the mouthpiece or pull the bung from the closure spilling or consuming the liquid.

Background art known to the author includes US2016213062, which discloses a protective cover for housing a vaporizer or modified electronic cigarette has an elongate body with a valve at its proximal end that may be opened to provide fluid access to the mouthpiece of a vaporizer housed within it. The elongate body may include a transparent and deformable region having a valve. The actuating button on a vaporizer housed within the body may be depressed by depressing the deformable region of the housing adjacent to the actuation button. The valve in the deformable region opens [0007] [0008] [0009] when the actuating button is depressed, providing fluid access to the intake valves of the modified electronic cigarette. The interior of the cover includes padding around the interior of its distal region and a piston biased by a spring to hold a housed modified electronic cigarette in a proper orientation within the cover. This is an overly complex and expensive mechanism directed solely at providing a means to keep the mouthpiece of an e-cigarette hygienically clean during conventional non-use. It cannot easily be adapted to function with a range of differently designed e-cigarettes.

US2018116295 this seeks to child proof access to the liquid chamber of the clearomiser (atomiser) only by providing a modified chamber closure/sealing assembly. For new e-cigarettes this present manufacturers with the great expense of modifying production processes and apparatus and still fails to child proof the mouthpiece. The claimed atomiser is of no use to existing designs of e-cigarettes.

WO2015/165064 discloses a child proof e-cigarette which is modified to make it difficult for a young child to disassemble the cigarette and access the liquid in the chamber. It is subject to similar technical disadvantages as US2018116295.

WO/2017/133982 discloses an container (essentially a jar or can) having a chamber closable by means of a child resistant cap. The cap is adapted by means of a “smoking article holder” to receive and hold a disassembled e-cigarette and accessories such as liquid. This is a large and cumbersome solution which is inconvenient to carry. The user must disassemble the e-cigarette and secure it to the smoking article holder, before returning the holder and associated cap to the jar. Conversely use requires the cap to be separated from the jar and the e-cigarette reassembled before use. The container is also a large extra item to carry around so that a user will be discouraged from using the container and so fail to implement the child proofing of their e-cigarette.

[0010] [0011] [0012] [0013] [0014] [0015]

The present invention aims to provide an apparatus to child proof an e-cigarette which addresses the technical problems identified above in relation to the prior art, providing an inexpensive, easily used, technically simple and reliable child proofing of a range of conventional e-cigarettes.

Summary of invention

Accordingly there is provided apparatus to child proof an e-cigarette wherein: the e-cigarette comprises a battery pack and a clearomiser, said battery pack having a battery pack connector adapted to separably connect the battery pack to a corresponding clearomiser connector in the clearomiser, one of said battery pack connector or clearomiser connector comprising a spigot adapted for reception in a socket forming the connector in the other of the clearomiser or battery pack and said apparatus comprises: an adapter having a hole adapted to fit closely around the spigot, whereby the adapter is secured to the e-cigarette assembled from the battery pack and clearomiser, said adapter deploying a first part of a child resistant securing mechanism to secure the second part of a child resistant securing mechanism mounted on a cover, whereby said cover encases the clearomiser when secured to the adapter.

Preferably the cover extends over the axial length of the clearomiser and is closed at the end remote from the adapter and open at the end for connection to the adapter.

The adapter is preferably provided by a ring formed of metal or plastics to have an axial hole such that the adapter cannot be removed from the spigot without disassembling the battery pack and clearomiser.

The first part of a child resistant securing mechanism is provided primarily on the rim of the adapter. Preferably the rim and cover are cylindrical. The disposition of the rim of the [0016] [0017] [0018] adapter determines the dimensions of the mouth of the cover. Accordingly the dimensions of the adapter are chosen so that the rim enables a cover mouth able to pass over the clearomiser without fouling. Preferably the adapter is cylindrical and the dimension of radius is sufficient that the rim extends beyond the periphery of the clearomiser.

In a first preferred embodiment the rim supports an external male screw thread. A female thread is formed on the interior of the open end of the cover. One of said male or female threads is supported on a sleeve freely rotatable around the adapter or within the cover. An asymmetric clutch mechanism is provided such that; when the cover is rotated in a tightening direction, usually clockwise, the sleeve locks and the threads can be easily joined; when the cover is rotated in a loosening direction the clutch disengages unless a sufficient axial force is applied pushing the cover towards the adapter. In a variant of the first embodiment the sleeve may be mounted on the adapter to rotate around a collar with the clutch mechanism acting between the collar and the sleeve. In a further variant the adapter may provide a collar with an internal female thread while the external thread is formed on the end of the cover which is received into the collar. The rotatable sleeve and clutch mechanism may be mounted on either of the sleeve or collar.

Preferably the thread on the adapter is formed integrally and is therefore fixed with the rotatable sleeve internal to the open end of the cover.

In a second embodiment the one of the adapter or the open end of the cover is provided with an arrangement of lugs disposed for reception in a corresponding arrangement of notches or slots formed in a flange extending from the other of the adapter and the cover. The lugs are disposed so that they can only pass through the slots in one relative rotary position of the of the adapter and cover. Thus the cover can only be separated from the adapter when precisely aligned. Alignment may be marked by indicators on the periphery of the respective adapter and cover. Preferably the flange is formed on a male sleeve projecting to overly the clearomiser.

[0019] A third embodiment preferred embodiment provides complementary male and female threads on each of the adapter and the inside of the open end of the cover. On one of the cover or the adapter is formed a resiliently radially displaceable detent mechanism. In a rest condition the detent is adapted to pass the rotation of the cover as it is threaded onto the adapter and to arrest the rotation of the cover in the opposite direction. The detent mechanism is connected to a manually operable lever to be displaceable from the rest position to a release position at which the cover can be rotated in a loosening direction to be withdrawn from encasing the clearomiser.

[0020] A fourth embodiment of the invention has a female screw thread formed internally near the opening of the cover. At least one lug is formed inside the mouth of the cover and relative to the thread remote from the closed end of the cover. The lug projects radially in from the open mouth of the cover. A male screw thread is formed on the periphery of the adapter to engage with the female screw thread. At least one lug is formed on the periphery of the adapter, on the side of the thread which, when installed, will be remote from the clearomiser. The region of the cover adjacent the mouth is configured to be resiliently deformable and the shape of the lugs is formed such that, as the cover is screwed onto the adapter an inclined ramping surface of the cover mounted lug will engage with a corresponding ramping surface of the lug on the adapter to deform the cover and allow the cover to be screwed on. However if the cover is torqued in the unscrewing direction radially extending abutting surfaces of the adapter lug and cover

10 18 lug engage to arrest rotation. By manually applying a radially inward pinching force to the periphery of the cover along a radius orthogonal to a radius passing through the lug the cover deforms to disengage the lugs and allow the cover to be unscrewed. In a variant of this embodiment a collar may be provided on the adapter with a female thread to receive a male thread formed on the outside of the cover mouth.

Brief description of drawings [0021] Embodiments of an apparatus for child proofing an electronic cigarette will now be described, by way of example only, with reference to the accompanying illustrative figures, in which:

Figure 1.1.0 is a plan view of a first embodiment assembled with an e-cigarette;

Figure 1.1.1 is a sectional plan view through the assembly of figure 1.1.0;

Figure 1.1.2 is an enlarged sectional view of the detail 1.3 in figure 1.1.1;

Figure 1.2.0 is an isometric SW view with hidden detail of the cover in Figure 1.1.0;

Figure 1.2.1 is an isometric SW enlarged detail of 1.2.0 ;

Figure 1.3.0 is a sectional plan view through a cylindrical sleeve of the first embodiment;

Figure 1.3.1 is a right hand elevation of the sleeve in figure 1.3.0;

Figure 1.3.2 is an isometric SW view of the sleeve in figure 1.3.1 ;

Figure 1.3.3 is an enlarged detail from figure 1.3.1;

Figure 1.4.0 is a plan view of an adapter from figure 1.1.1;

Figure 1.4.1 is a sectional plan of the adapter in figure 1.4.0;

Figure 2.1.0 is a plan view of a cover for the second embodiment;

Figure 2.1.1 is a sectional plan view through the cover in Figure 2.1.0;

Figure 2.1.2 is an end elevation showing the open mouth of the cover in Figure 2.1.1;

Figure 2.2.0 is a plan view of a clearomiser of the e-cigarette;

Figure 2.3.0 is a plan view of an adapter of the second embodiment;

Figure 2.3.1 is a front elevation of the second embodiment;

Figure 2.4.0 is a plan view of a battery pack of the e-cigarette;

Figure 2.5.0 is a plan view of the assembled apparatus and e-cigarette;

Figure 2.5.1 is a sectional plan view of the assembled apparatus and e-cigarette;

Figure 3.1.0 is a plan view of a cover of the third embodiment;

Figure 3.1.1 is a sectional plan view through the cover of 3.1.0;

Figure 3.1.2 is an enlarged end elevation of the mouth of the cover of 3.1.0;

Figure 3.2.0 is a plan view of a clearomiser of the e-cigarette;

Figure 3.3.0 is a plan view of an adapter of the third embodiment;

Figure 3.3.1 is an enlarged SE isometric view of the adapter of Figure 3.3.0;

Figure 3.4.0 is a battery pack of the e-cigarette;

Figure 3.5.0 is a plan view of the assembled apparatus and e-cigarette;

Figure 3.5.1 is a sectional plan view of figure 3.5.0;

Figure 4.1.0 is a plan view of a cover of the fourth embodiment;

Figure 4.1.1 is a SE isometric view of the cover of Figure 4.1.0;

Figure 4.1.2 is an enlarged detail of the mouth of the cover of the Figure 4.1.1;

Figure 4.2.0 is a plan view of a clearomiser of the e-cigarette;

Figure 4.3.0 is a plan view of an adapter of the fourth embodiment;

Figure 4.3.1 is an enlarged SE isometric view of 4.3.0;

[0022] Figure 4.4.0 is a broken view of a battery pack of the e-cigarette;

Figure 4.5.0 is a plan view of the assembled apparatus and e-cigarette; and

Figure 4.5.1 is a sectional plan view of 4.5.0.

[0023] [0024] [0025] [0026]

Description of embodiments

The E-cigarettes comprise a battery pack 1 and a clearomiser 2. The battery pack comprises a housing 3 adapted to enclose a battery 4. The battery is commonly a rechargeable battery of conventional chemistry and dimensions. The battery pack includes an LED display 5 to indicate the current charge state of the battery, a connector to operably connect the battery pack to the clearomiser. The connector has a spigot 6 bearing an external screw thread. The connector also includes electrical connections (not shown) to electrically connect the battery to the clearomiser. A manually operable power button 7 is provided for user operation of the e-cigarette.

The clearomiser 2 consists of a clearomiser connector 8 having a threaded connector socket 9 to receive the connector spigot 6 from the battery pack 1. The connector is adapted to seal a liquid containment chamber 10 provided in the clearomiser housing 11 by means of a bung 12 press fitted into a socket 13 of the housing. The connector is readily removable to allow the chamber 10 to be charged with a liquid. A heating element 14 is provided in fluid communication with a mouthpiece 15 of the e-cigarette and contacts one or more wicks 16 which depend into the chamber 10 to draw the liquid to the heating element. Electrical connections in the connector 8 communicate with the heating element 14 and the button 7.

The apparatus of the first embodiment comprises an adapter 17. The adapter 17 has a radially extending ring 18 sized to encircle the spigot 6 and to project radially beyond the clearomiser 2. A cylindrical sleeve 19 extends to project towards the mouthpiece when installed. A screw thread 20 is formed on the external surface of the sleeve 19.

The apparatus comprises a cover 21 comprising an elongate cylindrical tube closed at one end (on the left in the figures) and open mouthed at the other. A ring of saw tooth features 22 is formed integrally around the interior surface of the closed end. A rotatable sleeve 23 is retained in the mouth of the cover by press fitting past a deformable retainer ring 24 at the mouth of the cover.

[0027] A complimentary ring of saw tooth features 25 is formed on the outside of a closed end of the sleeve 23 which when assembled faces the saw tooth features 22. The length of the sleeve 23 is less than the distance between the apex of the saw tooth features 22 and the internal surface of the retainer ring 24 to leave a gap for longitudinal movement of the sleeve relative to the cover. A screw thread 26 is formed on the inside of the saw tooth cover ring 24 to thread onto the thread 20.

[0028] The saw tooth ring features are inclined such that when a user seeks to screw the cover 21 onto the adapter 17 oblique surfaces 22.1,25.1 of saw tooth features of rings 22 and 24 readily engage and rotate the sleeve 23 with the cover causing the cover to screw onto the adapter thread 20 until tight. However if the cover is rotated in the opposite direction the acutely inclined surfaces 22.2, 25.2 of the saw tooth features of saw tooth rings fail to engage readily unless a sufficient axial force is applied to urge the adapter and cover relatively towards each other, thus providing a child proof securing mechanism for the cover.

[0029] In the second embodiment of figures 2.1.0-2.5.0 the E-cigarette is identical to the E-cigarette previously described consisting of battery pack 1 having a connector spigot 6 and clearomiser2 with a corresponding connector socket.

[0030] The apparatus of the invention comprises an adapter 26 having a ring 27 sized to encircle the spigot 6 whereby the adapter can be irrotatably retained by socketing the adapter 26 over the spigot 6 and securing the spigot 6 into the connector socket 9 as with the first embodiment. The ring 27 supports an axially extending sleeve 28 at a radius which encircles the connector body. A flange 29 extends radially out from the sleeve 28 at the end remote from the ring 27. The flange 29 is perforated by three equiangularly spaced notches 30, 31 and 32.

[0031] The apparatus includes a cover 33 generally similar to the cover of the first embodiment, however, the inner surface is free of interruptions and cylindrical up to the mouth of the cover where three equiangularly spaced lugs 34, 35, 36 are provided to project radially inwards. The positions (radius and relative angle) and size of each lug complement the size of the notches 30, 31 and 32. Thus to secure the cover to the adapter, the lugs on the adapter must be aligned to pass through the notches. By making one notch 30 and one corresponding lug 36 of a different, in this example smaller, size relative to the others only one rotational position will allow the attachment or removal of the cover. An alignment marker 37 is placed on the external periphery of the mouth of the cover. A corresponding marker 38 is engraved into the periphery of the adapter. Thus the user rotationally aligns the markers in order to secure the cover to the adapter by axial displacement toward the battery pack 1 and then rotates the cover to secure it against axial displacement. Over displacement toward the battery is prevented by a portion of the ring 27 which extends radially beyond the sleeve 28 so that the lugs are trapped in an annular groove formed between the ring, the sleeve and the flange 29. Separation of the cover from the adapter requires realignment of the markers 37, 38.

[0032] The third embodiment illustrated in figures 3.1.0 to 3.5.1 provides an adapter 39 comprising a ring 40 sized to fit around the spigot 6 of battery pack 1. A sleeve 41 extends axially from the periphery of the ring 39 and is intended to overly the connector part of the clearomiser 2 when installed over the spigot 6 and clamped between the battery pack 1 and clearomiser 2. The exterior surface of the cylindrical sleeve 41 bears [0033] [0034] [0035] a male screw thread 42. Extending axially oppositely to the sleeve 41 is a detent mechanism. The detent mechanism includes a resiliently deformable spiral arm 43 extending radially out from the sleeve 41 in anti-clockwise direction as viewed from the battery pack 1. The base of the arm 43 is attached to a tab 44 in the form of an arch projecting towards the base of the battery pack 1 when installed.

The cover 45 has an open end inside of which is formed a female screw thread 46 compatible with the screw thread 42. A collar 47 is formed around the open end of the cover with an oversized internal bore in order to slide over the thread 42 as the thread 46 engages the thread 42. Within the collar bore an arresting projection 48 extends radially inwards to present an acute surface 49 to the detent as the cover is screwed onto the adapter and a radial surface 50 as the cover is unscrewed. When being screwed on the acute surface 49 acts as a ramp displacing the end of the spiral arm 43 radially in to allow passage of the arresting projection. The arm then returns by virtue of its resilience to its rest position. When the cover is unscrewed the radial surface 50 impinges on the end of the spiral arm 43 without any radial component of force to displace the arm 43 which consequently arrests unscrewing rotation.

In order to unscrew the cover the user must depress the tab 44 radially towards the battery pack 1 as the cover is unscrewed. The movement of the tab carries the arm 43 radially towards the battery pack 1 allowing the arresting projection 48 to pass.

The fourth embodiment shown in figures 4.1.0 to 4.5.1 has an adapter 51 comprising a radially extending ring 52. The ring supports an axially extending sleeve 53 intended to overly the connector of the clearomiser when installed. The external surface of the sleeve 53 bears a male screw thread 54. The peripheral surface of the ring 52 bears two [0036] [0037] diametrically opposite lugs 55. Each lug 55 has an acute ramping surface 56 and a radially extending arresting surface 57.

The cover is generally similar to previously described cases and has a female screw thread 58 to screw onto the male screw thread 54. A collar 59 extends around the open mouth of the cover extending beyond the thread so that a pair of diametrically opposed lugs 60 formed on the smooth inside of the collar 59 can be carried across the thread 54 without fouling the thread. Each lug 60 has a radial arresting surface 61 and an inclined ramping surface 62 disposed so that the ramping surfaces 62 engage the ramping surfaces 56 as the cover is screwed onto the adapter 51. When the cover is unscrewed from the adapter the arresting surfaces of the lugs engage preventing the cover from being unscrewed.

The collar 59 and or cover is fabricated to be resiliently deformable so that when the collar is squeezed radially in at diametrically opposed pressure points 63 orthogonal to the diameter of the lugs 60 the lugs 60 are urged radially out allowing the arresting surfaces to override the lugs 55 so that the cover can be unscrewed.

Claims (15)

Claims

1. Apparatus to child proof an e cigarette wherein: the e cigarette comprises a battery pack and a clearomiser, said battery pack having a battery pack connector adapted to separably connect the battery pack to a corresponding clearomiser connector in the clearomiser, one of said battery pack connector or clearomiser connector comprising a spigot adapted for reception in a socket forming the connector in the other of the clearomiser or battery pack and said apparatus comprises: an adapter having a hole adapted to fit closely around the spigot, whereby the adapter is secured to the e-cigarette assembled from the battery pack and clearomiser, said adapter deploying a first part of a child resistant securing mechanism to secure the second part of a child resistant securing mechanism mounted on a cover, whereby said cover encases the clearomiser when secured to the adapter.

2. Apparatus according to claim 1 wherein the cover extends over the axial length of the clearomiser and is open at the end for connection to the adapter.

3. Apparatus according to claim 1 or claim 2 wherein the adapter is provided by a ring having an axial hole such that the adapter cannot be removed from the spigot without disassembling the battery pack and clearomiser.

4. Apparatus according to claim 3 wherein the first part of a child resistant securing mechanism is provided on the rim of the adapter.

5. Apparatus according to claim 4 wherein:

the rim supports an external male screw thread, a screw thread is formed on one of the adapter or cover to operatively engage a screw thread formed on the other of the adapter or cover,, one of said threads is supported on a sleeve freely rotatable around the adapter or within the cover, an asymmetric clutch mechanism is provided such that, when the cover is rotated in a tightening direction, the sleeve locks and the threads can be easily joined; when the cover is rotated in a loosening direction the clutch disengages unless a sufficient axial force is applied to push the cover towards the adapter.

6. Apparatus according to claim 5 wherein the thread on the adapter is formed integrally and is therefore fixed with the rotatable sleeve internal to the open end of the cover.

7. Apparatus according to any of claims 1 to 3 wherein one of the adapter or the open end of the cover is provided with an arrangement of lugs disposed for reception in a corresponding arrangement of notches formed in a flange extending from the other of the adapter and the cover, said lugs disposed so that they can only pass through the slots in no more than one relative rotary position of the of the adapter and cover.

8. Apparatus according to claim 7 wherein the slots are formed in a flange supported by a sleeve extending from the ring of the adapter.

9. Apparatus according to either of claims 7 or 8 wherein alignment markers are provided on the cover and the adapter.

10. Apparatus according to any of claims 1 to 3 wherein there is provided complementary male and female threads on each of the adapter and the inside of the open end of the cover, on one of the cover or the adapter is formed a resiliently radially displaceable detent mechanism, in a rest condition the detent is adapted to pass the rotation of a lug formed on the other of the cover or the adapter to facilitate the cover being threaded onto the adapter and to arrest the rotation of the cover in the opposite direction, the detent mechanism is connected to a manually operable lever tab to be displaceable from the rest position to a release position at which the arresting action is disabled and the cover can be rotated in a loosening direction to be withdrawn from encasing the clearomiser.

11. Apparatus according to claiml 1 wherein the detent mechanism comprises a resiliently deformable member extending radially out from the adapter.

12. Apparatus according to claim 11 wherein the manually operable lever tab is integrally formed with the adapter.

13. Apparatus according to claim 10 or 11 wherein the lug is formed to project radially in from the cover and to override the thread on the adapter without fouling, said lug having a ramping surface to facilitate displacement of the resiliently deformable member as the cover is screwed on and an arresting surface to engage the resiliently deformable member without any radial force as the cover is unscrewed.

14. Apparatus according to any of claims 1 to 3 wherein:

the cover has a screw thread formed near the opening of the cover, at least one lug is formed adjacent the mouth of the cover and, relative to the thread, remote from the other end of the cover, the lug projects radially from the cover, a co-operable screw thread is formed on the periphery of the adapter to engage with the screw thread of the cover, at least one lug is formed on the periphery of the adapter, the region of the cover adjacent the mouth is configured to be resiliently deformable and the shape of the lugs is formed such that, as the cover is screwed onto the adapter an inclined ramping surface of the cover mounted lug will engage with a corresponding ramping surface of the lug on the adapter to deform the cover and allow the cover to be screwed on, when the cover is torqued in the unscrewing direction radially extending arresting surfaces of the adapter lug and cover lug engage to arrest rotation, and the radially outer of the adapter or the cover is deformable by the application of a compressive force along a radius orthogonal to a radius passing through the lug mounted on the radially outermost of the adapter or cover components, so that the component deforms to disengage the cover lug and adapter lug and allows the cover to be unscrewed.

15. Apparatus according to claim 14 wherein the screw thread formed on the adapter outside is a male screw thread formed on the outside of a peripheral sleeve of the adapter, and the screw thread formed on the cover is a female screw thread formed inside the mouth of the cover, the adapter lug extends radially out from the adapter and the cover lug extends radially in from the cover