Patent Publication Number: US-11661808-B2

Title: Inflatable down hole bag with inflation reagent release

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of PCT/AU2019/051146 filed Oct. 21, 2019, which claims priority to AU Patent Application No. 2018903977, filed Oct. 19, 2018, the entire disclosures of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to inflatable bags for use down a drill hole, such as to provide a platform or plug inside of the drill hole. 
     BACKGROUND 
     Inflatable bags are also known with a compressed inflation fluid in a canister, which is released into the bag in a controlled manner. Whilst these types of bags are effective the inflation fluids are typically gasses that have a GWP or health concerns greater than CO 2 . 
     Inflatable bags are known to have reagents, such as a carbonate or bicarbonate salt and an acid, which produce an inflation medium (typically CO 2 ) for inflating the bag when it is lowered inside the drill hole. The problem is that the reaction of the reagents needs to be slow enough to position the bag, but quick enough so that time is not wasted waiting for the reaction to be sufficiently progressed for the bag to be inflated enough for it to hold itself in place. A problem with existing solutions is that the reaction time is not sufficiently controlled, or that the reagent(s) clump or otherwise do not properly mix so as to react, or require breakage of a frangible component (typically holding the acid) which risks puncture of the bag from sharp remnants of the frangible component. An alternative is desired. 
     Any document, reference, patent application or patent that might be cited in this text is expressly incorporated herein in their entirety by reference, which means that it should be read and considered by the reader as part of this text. That the document, reference, patent application, or patent cited in this text is not repeated herein is merely for reasons of conciseness. 
     In this specification, where a literary work, act or item of knowledge (or combinations thereof), is discussed, such reference is not an acknowledgment or admission that any of the information referred to formed part of the common general knowledge as at the priority date of the application. Such information is included only for the purposes of providing context for facilitating an understanding of the inventive concept/principles and the various forms or embodiments in which those inventive 
     SUMMARY 
     According to an aspect of the present invention there is provided an inflatable down hole bag, comprising: 
     an inflatable body for holding an inflation fluid; 
     a container for holding one or more substances, the container being disposed inside of the inflatable body; 
     wherein the container comprises a closure for keeping the one or more substances in the container when the closure is in an inoperative state, the closure also for releasing the one or more substances from the container when the closure is in an operative state;
 
wherein release of the one or more substances causes an inflation fluid producing reaction within the inflatable body, thereby inflating the inflatable body; wherein, the container comprises at least two separated chambers, each chamber for holding a respective one of the substances, wherein the closure comprises a stopper for closing a respective opening to one of the chambers, wherein the closure further comprises an actuator for removing each stopper from the respective opening so as to release each substance from each respective chamber.
 
     Preferably, the actuator comprises a stopper withdrawing mechanism and a trigger, wherein pressing on the trigger operates the stopper withdrawing mechanism. Typically, the trigger comprises a contact tab for receiving pressure to operate the trigger. 
     Preferably, the stopper in is an interference fit with the opening. Preferably the stopper comprises an annular rib in the interference fit with a groove of the opening. 
     Preferably, the stopper mechanism restrains the stopper from opening until the trigger mechanism is activated. Preferably the stopper comprises a releasable holder for restraining the stopper. Preferably, the holder comprises an upper member for preventing upward movement of the stopper relative to the opening. Preferably, the holder comprises a lower member for preventing downward movement of the stopper relative to the opening. Preferably, the stopper comprises a flange extending substantially laterally relative to the opening. Preferably the upper member is disposed above the flange. Preferably the lower member is disposed below the flange and is preferably initially not in contact with the flange, but when the trigger is activated the lower member moves underneath the flange. Preferably, the holder comprises a vertical portion extending between upper member and the lower member. Preferably vertical portion pushes against the flange when the trigger is activated. 
     Preferably, the stopper withdrawing mechanism comprises a wedge mechanism for lifting the stopper relative to a body of the container. 
     Preferably, the stopper withdrawing mechanism comprises a pivot mechanism for pivoting a side of the stopper relative to a body of the container. 
     Preferably, the stopper withdrawing mechanism comprises a wedge mechanism for lifting the stopper relative to a body of the container and a pivot mechanism for pivoting a side of the stopper relative to a body of the container. Typically, the wedge mechanism and pivot mechanism are substantially sequential in operation. 
     Alternatively, the stopper withdrawing mechanism comprises an engagement mechanism for engaging a portion of the stopper and a pivot mechanism for pivoting a side of the stopper relative to the opening of the container. In an embodiment the engagement mechanism comprises the lower member and the pivot mechanism comprises the vertical portion. 
     In an embodiment, the inflatable body comprises a reaction bag within the inflatable body within which the container is disposed. 
     Preferably, the reaction bag comprises a sloped internal surface when the inflatable down hole bag is oriented for lowering into the hole such that the substances are urged to move to a lowermost part of the reaction bag under the influence of gravity. 
     Preferably, the reaction bag comprises a first reagent substance within one or more dissolvable skins and at least one of the substances within the container is a second reagent capable of dissolving the dissolvable skin, and the first and second reagents when in contact produce or contribute to the production of the inflation fluid producing reaction. 
     Preferably, the or each dissolvable skin with the first reagent therein is in the form of a tablet. In an embodiment the rate of the inflation fluid producing reaction is selectable by selecting the size of the or each of the tablets. 
     According to an aspect of the present invention there is provided a container for release of a reactive substance into an inflatable down hole bag, comprising: 
     a container body for holding one or more substances; and 
     a closure for keeping the one or more substances in the container when the closure is in an inoperative state, the closure also for releasing the one or more substances from the container when the closure is in an operative state; 
     wherein release of the one or more substances causes an inflation fluid producing reaction within the inflatable body, thereby inflating the inflatable body; wherein, the container comprises at least two separated chambers, each chamber for holding a respective one of the substances, wherein, the closure comprises a stopper for closing a respective opening to one of the chambers. In an embodiment, the closure further comprises an actuator for removing each stopper from the respective opening so as to release each substance from each respective chamber. 
     In an embodiment, the actuator comprises a stopper withdrawing mechanism and a trigger, wherein pressing on the trigger operates the stopper withdrawing mechanism. Typically, the trigger comprises a contact tab for receiving pressure to operate the trigger. 
     Preferably, the stopper in is an interference fit with the opening. Preferably the stopper comprises an annular rib in the interference fit with a groove of the opening. 
     Preferably, the stopper withdrawing mechanism restrains the stopper from opening until the trigger mechanism is activated. Preferably the stopper comprises a holder for restraining the stopper. Preferably, the holder comprises an upper member for preventing upward movement of the stopper relative to the opening. Preferably, the holder comprises a lower member for preventing downward movement of the stopper relative to the opening. Preferably, the stopper comprises a flange extending substantially laterally relative to the opening. Preferably the upper member is disposed above the flange. Preferably the lower member is disposed below the flange and is preferably initially not in contact with the flange, but when the trigger is activated the lower member moves underneath the flange. Preferably, the holder comprises a vertical portion extending between upper member and the lower member. Preferably vertical portion pushes against the flange when the trigger is activated. 
     In an embodiment, the stopper withdrawing mechanism comprises a wedge mechanism for lifting the stopper relative to a body of the container. In an embodiment, the stopper withdrawing mechanism comprises a pivot mechanism for pivoting a side of the stopper relative to a body of the container. Typically, the wedge mechanism and pivot mechanism are substantially sequential in operation. 
     Alternatively, the stopper withdrawing mechanism comprises an engagement mechanism for engaging a portion of the stopper and a pivot mechanism for pivoting a side of the stopper relative to the opening of the container. In an embodiment the engagement mechanism comprises the lower member and the pivot mechanism comprises the vertical portion. 
     According to an aspect of the present invention there is provided a method of inflating a down hole bag, comprising: 
     providing an inflatable bag having an inflatable body for holding an inflation fluid; the bag comprising a container for holding two or more substances in at least two separated chambers, each chamber for holding a respective one of the substances, the container being disposed inside of the inflatable body, the container comprising a closure which comprises a stopper for closing a respective opening to one of the chambers;
 
activating an actuator of the container so as to change it from an inoperative state where the one or more substances in the container a held therein to an operative state wherein upon the change from the inoperative state to the operative state removes each stopper from the respective opening so as to release each of the substances of each respective chamber of the container into the inflatable body;
 
wherein release of the one or more substances causes an inflation fluid producing reaction within the inflatable body, thereby inflating the inflatable body.
 
     According to an aspect of the present invention there is provided a method of opening a container for release of a reactive substance into an inflatable down hole bag, comprising: 
     providing a container having a body for holding two more substances in at least two separated chambers, each chamber for holding a respective one of the substances; and a closure for keeping the substances in the container when the closure is in an inoperative state, the closure comprises a stopper for closing a respective opening to one of the chambers, the closure also comprising an actuator for releasing the substances from the container when the closure is in an operative state;
 
activating the closure so as to removes each stopper from the respective opening so as to release the substances such that they cause an inflation fluid producing reaction within the inflatable bag.
 
     Any document, reference, patent application or patent that might be cited in this text is expressly incorporated herein in their entirety by reference, which means that it should be read and considered by the reader as part of this text. That the document, reference, patent application, or patent cited in this text is not repeated herein is merely for reasons of conciseness. 
     In this specification, where a literary work, act or item of knowledge (or combinations thereof), is discussed, such reference is not an acknowledgment or admission that any of the information referred to formed part of the common general knowledge as at the priority date of the application. Such information is included only for the purposes of providing context for facilitating an understanding of the inventive concept/principles and the various forms or embodiments in which those inventive 
     Various aspects described herein can be practiced alone or combination with one or more of the other aspects, as will be readily appreciated by those skilled in the relevant art. The various aspects can optionally be provided in combination with one or more of the optional features described in relation to the other principal aspects. Furthermore, optional features described in relation to one example (or embodiment) can optionally be combined alone or together with other features in different examples or embodiments. 
     For the purposes of summarising the aspects, certain advantages and novel features have been described herein above. It is to be understood, however, that not necessarily all such advantages may be achieved in accordance with any particular embodiment or carried out in a manner that achieves or optimises one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features of the invention are described in the following description of several non-limiting embodiments thereof. This description is included solely for the purposes of exemplifying the inventive principles. It should not be understood as a restriction on the broad summary, disclosure or description as set out above. The description is made with reference to the accompanying drawings in which: 
         FIG.  1    is a schematic see-through elevation of an inflatable down hole bag according to an embodiment of the invention; 
         FIG.  2    is a schematic elevation of a reagent container according to an embodiment of the invention, with a closure in place, and the container oriented to be in a preferred activation position, which is inverted from its operational position; 
         FIG.  3    is a schematic rear elevation of the reagent container of  FIG.  2   , with the closure of the container removed; 
         FIG.  4    is a front elevation of the closure of  FIG.  2   ; 
         FIG.  5    is a plan view of the closure of  FIG.  2   , in an inoperative state; 
         FIG.  6    is an isometric view of a cross section through A-A of  FIG.  5   , in the inoperative state; 
         FIG.  7    is an elevation of the cross section through A-A of  FIG.  5   , in the inoperative state; 
         FIG.  8    is an isometric view of a cross section through A-A of  FIG.  5   , at a first transition point between the inoperative state and an operative state; 
         FIG.  9    is an elevation of the cross section through A-A of  FIG.  5   , in the first transition point of  FIG.  8   ; 
         FIG.  10    is an isometric view of a cross section through A-A of  FIG.  5   , at a second transition point between the inoperative state and the operative state; 
         FIG.  11    is an isometric view of a cross section through A-A of  FIG.  5   , at a third transition point between the inoperative state and the operative state; 
         FIG.  12    is an elevation of the cross section through A-A of  FIG.  5   , in the third transition point of  FIG.  11   ; 
         FIG.  13    is an isometric view of a cross section through A-A of  FIG.  5   , at a fourth transition point between the inoperative state and the operative state; 
         FIG.  14    is an elevation of the cross section through A-A of  FIG.  5   , in the fourth transition point of  FIG.  13   ; 
         FIG.  15    is an isometric view of a cross section through A-A of  FIG.  5   , at a fifth transition point between the inoperative state and the operative state; 
         FIG.  16    is an elevation of the cross section through A-A of  FIG.  5   , in the fifth transition point of  FIG.  13   ; 
         FIG.  17    is a front isometric view of the closure in the fifth transition point between the inoperative state and the operative state; 
         FIG.  18    is a lower isometric view of the closure with a stopper mechanism being released from the remainder of the closure, so that the closure is in the operative state; 
         FIG.  19    is an isometric view of an alternative embodiment of the closure of  FIG.  2   ; 
         FIG.  20    is a vertical cross section (through F. 20 -F. 20  of  FIG.  22   ) of a further alternative closure of a reagent container according to another embodiment of the invention; 
         FIG.  21    is an isometric view of the closure of  FIG.  20   ; 
         FIG.  22    is a plan view of the closure of  FIG.  21   ; and 
         FIG.  23    is a horizontal cross section (though F. 23 -F. 23  of  FIG.  20    as if it were not a cross-section) of the closure of  FIG.  21   . 
     
    
    
     In the figures, like elements are referred to by like numerals throughout the views provided. The skilled reader will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to facilitate an understanding of the various embodiments exemplifying the principles described herein. Also, common but well understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to provide a less obstructed view of these various embodiments. It will also be understood that the terms and expressions used herein adopt the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein. 
     It should be noted that the figures are schematic only and the location and disposition of the components can vary according to the particular arrangements of the embodiment(s) as well as of the particular applications of such embodiment(s). 
     Specifically, reference to positional descriptions, such as ‘lower’ and ‘upper’, and associated forms such as ‘uppermost’ and ‘lowermost’, are to be taken in context of the embodiments shown in the figures, and are not to be taken as limiting the scope of the principles described herein to the literal interpretation of the term, but rather as would be understood by the skilled reader. 
     Embodiments described herein may include one or more range of values (eg. size, displacement and field strength etc). A range of values will be understood to include all values within the range, including the values defining the range, and values adjacent to the range which lead to the same or substantially the same outcome as the values immediately adjacent to that value which defines the boundary to the range. 
     Other definitions for selected terms used herein may be found within the detailed description and apply throughout. Unless otherwise defined, all other scientific and technical terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the embodiment(s) relate. 
     DETAILED DESCRIPTION 
     The words used in the specification are words of description rather than limitation, and it is to be understood that various changes may be made without departing from the spirit and scope of any aspect of the invention. Those skilled in the art will readily appreciate that a wide variety of modifications, alterations, and combinations can be made with respect to the above described embodiments without departing from the spirit and scope of any aspect of the invention, and that such modifications, alterations, and combinations are to be viewed as falling within the ambit of the inventive concept. 
     Throughout the specification and the claims that follow, unless the context requires otherwise, the word “comprise” or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. 
     Furthermore, throughout the specification and the claims that follow, unless the context requires otherwise, the word “include” or variations such as “includes” or “including”, will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. 
     Referring to  FIG.  1   , there is shown an inflatable down hole bag  10  comprising an inflatable body for holding an inflation fluid. The inflatable body comprises an outer bag  12  and an inner bag  14 . The inner bag  14  is inside of the interior  16  of the outer bag  12 . The inner bag  14  is smaller in size than the outer bag  12 , but large enough so that when inflated it is of a suitable size to fill a circumference of and a portion of the length of a drill hole. Inside  18  of the inner bag  14  is a container  30  for holding one or more reagent substances. The inside of the bag  14  may also comprises one or more reagent substances are described further below. 
     Referring to  FIG.  2   , the container  30  comprises a closure  50  for keeping the one or more reagent substances in the container when the closure is in a closed configuration of an inoperative state. The closure  50  is also able to release the one or more reagent substances (for example a salt  32  and an acid  34 ) from respective chambers (in this case chambers  42  and  44 ) of the container  50  when the closure  50  is in an open configuration of an operative state. 
     The released reagent substances  32  and  34  mix at  36  and (chemically) react causing release of an inflation fluid  38 , such as carbon dioxide (CO 2 ) gas, thereby inflating inner bag  14 , and in turn the outer bag  12 , and thus the inflatable body. 
     The inside  18  of the inner bag  14  houses the reaction. In order to aid in the mixing of the reagent substances the inner reaction bag  14  comprises a sloped internal surface  20  when the inflatable down hole bag  10  is oriented for lowering into the drill hole such that the substances are urged to move to a lowermost part  22  of the reaction bag under the influence of gravity. Further the container  30  is fixed (such as by adhesive) to a side wall of the inner bag  14  so as to be disposed relatively high above the lowermost point  22 . The drop of the falling substances  32  and  34  from the container  30  on impact with the mix  36  preferably causes agitation to the mix  36 , thereby encouraging complete reaction of the substances and avoiding clumping. Such is useful when faster reaction time (and in turn inflation time) is desired. 
     However, a slower reaction time may also be desired. In that instance one or some of the reagent substances may be within a tablet  35  having (or not having) a dissolvable skin or coating. Thus, for instance when liquid, such as acid  34 , is released from the container the acid will begin to dissolve the skin of the tablet  35 , or the tablet  35  will be designed to be a rapidly dissolving tablet (RDT). As the acid contacts the reagent substance(s) therein (such as bicarbonate or carbonate salt) this will react thereby creating the inflation fluid  38 , but only after the delay of the acid dissolving the skin has occurred. The reaction rate can also be controlled by the size of the tablet or tablets  35 , due to the reaction rate being dependent on the surface area of the or each tablet  35  undergoing reaction or the tablet composition as in the case of a RDT without a skin. 
     The tablet(s)  35  may be loose within the inner bag  14 , adhered to a position in the region of the lower most point  22  or released from the container  30 . 
     It will be appreciated that reagent substances other than a carbonate/bicarbonate salt and an acid may be used and indeed more than two reagent substances may be used. For example, the acid may be in a dry solid form (eg. citric acid granules) that is activated when wet, such as by the release of water from one or the chambers of the container  30 . Further the container  30  may only have one of the reagent substances when another is already in the inner reaction bag  14 . 
     The amounts/proportions of the reagent substances can be selected for the size of the bag  10  and the amount of inflation fluid  38  to be produced. In this example chamber  42  is smaller than chamber  44  and the chambers  42  and  44  are connection by a web  40 . In an embodiment the chambers  42 ,  44  have screw tops  46  and  48 , respectively. A cap  130  having a hole  100  substantially axially therethough is screwed to each screw top  46 ,  48 . In the hole  100  is a stopper having a disc portion  72  which is held in placed by an interference or taper fit (such as a snap fit arrangement). The hole  100  is defined by a lip  70 . 
     Referring to  FIG.  19   , an embodiment of the closure  50  comprises the caps  130 , a release actuator assembly  120  (shown separated in  FIG.  18   ) and a skirt  60 , which is clipped to the underside of the caps  130  so as to hold the skirt  60  in place. As shown in  FIG.  19   , the release actuator assembly  120  is held in place within the skirt  60  by wings  114  extending from a tab  82 , in the form of a plate, of the release actuator assembly  120 . The wings  114  interfere with protrusions  112  on the inside of the skirt  60 . In an embodiment, the skirt  60  extends down (when oriented as per  FIG.  1   ) from the container end of the caps  130 , across the height of the caps  130  as indicated by  54 ,  56 , and to a distance that houses the release actuator assembly  120 . The skirt  60  has a void therein for housing the release actuator assembly  120 . The void also allow allows clear passage of the reagent substance  32 ,  34  exiting the container  30  when the release actuator assembly  120  has being activated. The skirt  60  also has an opening  52  in a side which allows pressing or contact with plate  82  so as to trigger activation of the release actuator assembly  120 . 
     In an embodiment, the release actuator assembly  120  comprises a stopper withdrawing mechanism and a trigger, wherein pressing on the trigger operates the stopper withdrawing mechanism. The trigger comprises the plate  82  for receiving pressure to operate the trigger. Each stopper  72  (and  72 ′) comprises a disc forming the body of the stopper  72  which seals the respective hole  100  in the respective cap  130 , which hole  100  is defined by the respective lip  70  (and  70 ′), an axially aligned projection  74  (see  FIGS.  6  and  7   ) and a hat  76  preferably in the form of a circular flange. The projection  74  and the hat  76  form a T-shape in cross section as best seen in  FIG.  7   , and with the disc, form an H shape in cross section. 
     The skirt  60  also comprises a platform  90  between the lips  70 ,  70 ′. The release actuator assembly  120  further comprises a wedge member  84 , a latch  80  and a slide  88 . The release actuator assembly  120  moves as the tab  82  is pushed. In particular the slide  88  slides over the platform  90  as the tab  82  is pushed. The wedge member  84  projects from the tab  82  and has a clearance  92  underneath it. The wedge member  84  has a sloped surface portion as seen in  FIG.  7    and an upper surface portion substantially parallel with the slide  88 . The distance between the upper surface portion and the underside is substantially the same as the distance between the hat  76  and the disc part of the stopper  72 . The latch  80  also projects from the tab  82  and has a hooked end as seen in  FIG.  7   . The latch  80  is of a length substantially the same as the diameter of the hat  76 . 
     The release actuator assembly  120  is in an inoperative state as shown in  FIGS.  6 ,  7  and  19   . To operate the release actuator assembly  120  a user presses the tab  82  as indicated by P 1  in  FIG.  8   . 
     Pressing the tab  82  causes the wings  114  to flex until they are released from the protrusions  112 , such that the protrusions no longer hold the wings  114  and thus the release actuator assembly  120  captive in the skirt  60 . Further, slide  88  moves along the platform  90  and the wedge member  84  moves into the space between the hat  76  and the disc of the stopper  72  until the sloped surface portion contacts the hat  76  as indicated by C in  FIG.  9   . Contact of the sloped surface portion of the wedge member  84  as movement L occurs lifts the hat  76  as indicated by L, in  FIG.  9   . Lifting of the hat  76  causes lifting of the disc of the stopper  72  out from its interference fit in the hole defined by the lip  70 . In an embodiment this occurs at one side of the stopper  72 . 
     In an embodiment (not shown) the platform or the slide may comprise a ramp for adding a displacement of the wedge member  84  to the action (providing a similar effect to the wedging of the wedge member  84 ) with movement of the release actuator assembly  120 . 
     As the tab  82  continues to be pushed, as indicated by P 2  in  FIG.  10   , the wedge member  84  continues to be inserted between the hat  86  and the disc of the stopper  72  and this continues to lift the hat  76  and thus the stopper  72 . The disc of the stopper  72  moves into the clearance  92 . The hook of the latch  80  moves across the upper surface of the hat  76 . The latch  80  may be bent along its length as this occurs. 
     As the tab  82  is continues to be pushed, as indicated by P 3  in  FIG.  11   , the wedge member  84  continues to be inserted between the hat  86  and the disc of the stopper  72  until the upper surface portion contacts the hat  76 . In an embodiment the disc of the stopper  72  is at least partly (and in some embodiments fully) removed from the hole  100 . The hooked end  96  of the latch  80  (resiliently) falls off the upper surface of the hat  76  and latches onto the hat  76 . The stopper  72  via the hat  76  is thus held by the release actuator assembly  120  via the latch  80 . 
     As the tab  82  is continues to be pushed, as indicated by P 4  in  FIG.  13   , the slide  88  falls off the stepped end of the platform  90  as indicated by D (or in the embodiment shown in  FIG.  19    runs down a slide  96 ) causing the tab  82  to pivot as indicated by U and T. In turn the stopper  72  will pivot as indicated by R. The pivoting is about the side of the stopper  72  opposite the tab  82 . 
     As the tab  82  is continues to be pushed as indicated by P 5  in  FIG.  15    the pivoting continues, which continues to open the hole  100  until the stopper  72  is fully released from the hole  100  as indicated by  FIG.  17   . Typically, this occurs while the container  50  is open side up. The container  50  is thus in an open state. 
     The bag  10  is then inverted and lowered into the drill hole (not shown). In doing so the container is inverted to be in the orientation shown in  FIG.  1   . The release actuator assembly  120  holding the stopper  72  then falls away as indicated by F and the contents of each chamber  42 ,  44  of the container  30  then empty, as indicated by E 1  and E 2 , into the inner reaction bag  14  so as to collect at the lowermost point  22  and commence the inflation fluid releasing reaction so as to inflate the bag  10 . 
     Referring to  FIG.  20   , an alternative embodiment of the closure  150 , which comprises an alternative release actuator assembly  220 , is shown. The closure  120  comprises similar components to closure  50 , namely the closure comprises the caps  130  and a skirt  60 , which is clipped to the underside of the caps  130  so as to hold the skirt  60  in place. 
     The release actuator assembly  220  is held in place, for example using similar wings  114  (to those of the release actuator assembly  120 ) extending from a tab  82  of the release actuator assembly  220 . The wings  114  interfere with protrusions  112  on the inside of the skirt  60 . 
     In an embodiment, the release actuator assembly  220  comprises a stopper withdrawing mechanism, similar in function to the embodiment of  120 , but different in form, and a trigger. Pressing on the trigger operates the stopper  72  withdrawing mechanism. The trigger comprises the plate  82  for receiving pressure to operate the trigger. Each stopper  72  (and  72 ′) comprises a disc forming the body of the stopper  72  which seals the respective hole  100  in the respective cap  130 , which hole  100  is defined by a respective lip  70  (and  70 ′). The stopper  72  also comprises an axially aligned projection  74  and a hat  76 . The projection  74  and the hat  76  form a T-shape in cross section, and with the disc form a somewhat H shape in cross section. 
     The skirt  60  also comprises a platform  90  between the lips  70 ,  70 ′ in the form of a projecting stripe that extends from the skirt  60 . The release actuator assembly  120  further comprises a holder for restraining the stopper  72 , a slide  88  and the platform  90 . The release actuator assembly  220  moves as the tab  82  is pushed. In particular, the slide  88  slides over the platform  90  as the tab  82  is pushed. In an embodiment, walls  186 ,  186 ′ are on the sides (preferably outsides) of the platform  90  and another (complementary) platform  90 ′ and ensure the release actuator assembly  120  is restricted to move in a direction aligned with the lengths of the platforms  90 ,  90 ′. The holder comprises an upper member  180  disposed above the hat  76  for preventing upward movement of the stopper  72  relative to the opening. Thus, the stopper  72  is held closed until the trigger is activated. 
     The release actuator assembly  120  is held in within the skirt  60  by a retention mechanism until the trigger is fully actuated. In an embodiment, the retention mechanism comprises a downward projection  190  having a flange  196  and in this case opposite facing flanges. The flanges  196  fit between and may contact the caps  130 . Connected to the skirt  60  and the platform  90  is inward projection  192  (for each cap) against which the downward projection  190  can slide and under which the flange  196  slides. The inward projection  192  retains the flange  196  and thus the projection  190  and in turn the release actuator assembly  120  until the flange reaches an opening  194 , whereupon the flange  196 , which is sized to fit through the opening  194 , can move though so as to release the release actuator assembly  120 . The opening  194  is positioned such that the trigger has engaged the stopper  72 , and in some embodiments, removes the stopper  72  from the opening  100 . 
     Preferably, the holder comprises a lower member  206 ,  208  disposed below the hat  76  and between with the projection  74  is able to be received for preventing downward movement of the stopper  72  relative to the opening. Preferably the lower member  206 ,  208  is preferably initially not in contact with the hat  76 , but when the trigger is activated the holder and in particular the lower member  206 ,  208  moves underneath the flange of the hat  76 . Preferably, the holder comprises a vertical portion  202 ,  203 ,  204  extending between upper member  180  and the lower member  206 ,  208 . Preferably the vertical portion  202 ,  203 ,  204  is curved to conform to the shape of a matching part of the hat  76 . Preferably a rear part  203  of the vertical portion (seen in  FIG.  23   ) pushes against the matching part of the hat  76  when the trigger is activated, thus the holder comes into engagement with the hat  76 . 
     The release actuator assembly  220  is in an inoperative state as shown in  FIGS.  20  to  22   . To operate the release actuator assembly  120  a user presses the tab  82  as indicated by P 1  in  FIG.  22   . 
     Pressing the tab  82  causes the wings  114  to flex until they are released from the protrusions  112 , such that the protrusions no longer hold the wings  114  and thus the release actuator assembly  120  captive in the skirt  60 . 
     Further, slide  88  moves along the platform  90  and the holder engages the hat  76 . Then, when the rear part  203  of the vertical portion contacts the hat  76 , further pressure on the tab  82 , indicated by P 2 , causes the rear part  203  to lift and pivot the stopper  72 . A wedge mechanism similar to that described above may also be used at this point. In an embodiment the opening  194  is defined by a ramped surface  198 , which acts as a wedge mechanism by pushing the flange  196  relatively upward, which in turn causes the release actuator assembly  120  and the held stopper  72  to be lifted. Lifting of the stopper  72  lifts it out from its interference fit in the hole  100  defined by the lip  70 . 
     This embodiment of the release actuator assembly  220  is able to hold the stopper  72  in place against a force this might overcome the interference fit. Accordingly, this embodiment may use a lower force requirement to dislodge the stopper  72  from the opening  100  in comparison to the embodiment of the release actuator assembly  120  that used resilience of the latch  80  to hold the stopper  72  in place and the wedge mechanism, including wedge member  84 , to overcome the interference fit so as to lift the stopper  72  from the hole  100 . 
     When the release actuator assembly  220  has fully released the stopper  72  from the hole  100  it can fall away and the contents of each chamber  42 ,  44  of the container  30  can then empty, as indicated by E 1  and E 2  in  FIG.  1   , into the inner reaction bag  14  so as to collect at the lowermost point  22  and commence the inflation fluid releasing reaction so as to inflate the bag  10 . 
     The skilled reader would readily appreciate the nature of the materials appropriate for making the components of the embodiments of the arrangements described herein. Modifications and variations as would be apparent to the skilled addressee are intended to be covered by the accompanying claims. 
     Future patent applications maybe filed in Australia or overseas on the basis of, or claiming priority from, the present application. It is to be understood that the following claims are provided by way of example only and are not intended to limit the scope of what may be claimed in any such future application. Features may be added to or omitted from the provisional claims at a later date so as to further define or re-define the invention or inventions.