Abstract:
A frozen beverage device to convert a liquid beverage into a semi-frozen or frozen form has inner and outer walls forming a refrigerant cavity containing a refrigerant material with a freezing point below the freezing point of the liquid, the refrigerant material occupying at least 80% of the volume of the refrigerant cavity. The outer wall has a base portion which can be moved from a first position, where the liquid is at least semi-frozen, to a second position where the internal pressure in the refrigerant cavity urges the inner wall outwardly towards the outer wall so that the refrigerant material contacts a maximum area of the surface of the inner wall in the refrigerant cavity for maximum heat transfer and to minimise constriction of access to the frozen beverage. Alternative methods to seal the inner and outer walls to close the refrigerant cavity are also disclosed.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    THIS INVENTION relates to an improved method and cup for operation of a frozen beverage device; and to methods of producing frozen beverages using the device. 
         [0003]    The invention is particularly suitable for, but not limited to, apparatus for making frozen beverages in semi-frozen “slurry” or “slushie” form; and to such a frozen beverage device which may be used as a toy or plaything. 
         [0004]    Throughout the specification, the term “slurry” shall be used to include a mixture of liquid/semi-liquid, liquid/frozen and/or semi-liquid/frozen portions of the liquid. 
         [0005]    2. Prior Art 
         [0006]    Machines to produce so-called “slurry”-type drinks, e.g., of well-known beverages such as “Coca-Cola”, “Pepsi Cola” and “Schweppes Lemonade” (all registered trade marks) are well-known and commonly found in take-away food outlets and convenience stores. However, these machines are expensive to manufacture and install; and are not suitable for, e.g., domestic use; or for the manufacture of a wide range of “slurry”-style beverages, including alcoholic beverages such as cocktails. 
         [0007]    International Patent Application PCT/AU2005/001895 (=International Publication WO 2006/063401) (Bucceri, Alfio) disclosed a method of and apparatus for converting a liquid in a container to a semi-frozen slurry or to frozen ice particles. 
         [0008]    The freezing device was a purposely-designed cup capable of holding a refrigerant between 2 flexible walls; and could be provided in numerous sizes and shapes. 
         [0009]    The refrigerant between the walls of the cup consisted of salt and water, or a similar brine-type solution, that lowers the freezing temperature of the solution. The refrigerant was placed between the walls, and air was excluded before sealing the two walls of the cup that was formed. 
         [0010]    In this way, a vacuum was formed between the walls which allowed for the refrigerant to be disbursed high onto the side walls of the cup or vessel, or other freezing means, and then a beverage was added to be chilled or frozen. 
         [0011]    The cup was then subjected to squeezing by the consumer&#39;s hands for a pre-determined period of time, and the beverage was quickly chilled, or could be totally or partially frozen. The beverage was then ready for consumption. 
         [0012]    It was found that when using that apparatus and method, the refrigerant between the wall cavities would drop by gravity to the bottom of the cup, and create a pressure on the flexible and pliable inner wall. 
         [0013]    The inner wall was made from flexible pliable material such as silicon, TPU, PE, EVA, thin-sheeted aluminum, copper foil, or food grade polyurethane- or polyethylene material. 
         [0014]    The problem did not affect the working of the apparatus; and during the freezing of the cup and the squeezing of the cup, the problem was not readily noticeable, and the device worked very well and did what it was designed to do during these processes. 
         [0015]    In fact, it was the pressure of the liquid refrigerant on the flexible inner wall of the cup that made this a workable and innovative product. 
         [0016]    During the use of the apparatus, the double-walled cup containing the refrigerant was frozen in the freezer, and the liquid coolant would fill the total void between the cup walls to ensure that heat transfer occurred to all parts of the inner cup, from the base to the top of the cup. 
         [0017]    The refrigerant was distributed in this manner by freezing the cup in an upside down position i.e. turning the cup upside down, when in the freezer, to ensure that the refrigerant was easily and efficiently spread. 
         [0018]    Then, when the consumer took the cup from the freezer and filled the cup with a cold liquid and squeezed the sides, the transfer of heat caused the ice crystals that were formed on the inner wall of the apparatus to be dislodged and to float to the top of the cup. It has been shown that cup worked perfectly and efficiently in making a slushy drink in this manner. 
         [0019]    However, in doing so, there was a problem with the cup that became relevant during the consumption of the beverage by the user. 
         [0020]    The problem that occurred is that the melting refrigerant between the inner walls of the cup drops by gravity to the base of the cup, as the refrigerant is converted from ice to liquid and released the cold. 
         [0021]    The inner wall of the cup would expand at the base as with the user consumed the frozen beverage and caused the amount of frozen beverage to diminish within the cup. 
         [0022]    This caused the top of the flexible inner wall to move inwards at the top of the cup, while at the same time bulging out at the base of the cup as the liquid refrigerant in the lower side pushed against the inner wall. 
         [0023]    The effect of this action was that the perfectly formed inner wall can now resemble a wine-glass shape with the bottom part of the inner wall constricting around the remaining frozen beverage remaining in the cup. 
         [0024]    As this is the nature of the flexible inner wall, the result is understandable, and because of the nature of the resilient flexible material it was still possible to maneuver the spoon through the constriction to consume and retrieve the remaining e.g. 15% to 20% of the frozen beverage. 
         [0025]    Another problem caused by the above described constriction was that the cleaning of the cup could be more difficult due to this constriction and the liquid refrigerant pressure on the base of the inner wall. 
         [0026]    International. Patent Application PCT/AU2008/001923 (=International Publication WO 2009/079721) (Bucceri, Alfio) disclosed an alternative apparatus, and method, for converting a liquid in a closable container to a semi-frozen slurry or to frozen ice particles, where freezing devices, with thin deformable walls, contain refrigerant to form a thin layer of ice/ice crystals on the deformable walls, the ice crystals being released therefrom due to agitation of the liquid in the container by shaking/rotation and/or squeezing on the container and/or the removable closure. 
         [0027]    Experience with the prior art devices described above has identified some limitations with those devices e.g. the frozen beverage may be difficult to remove from the container and/or the freezing period may be too slow to be acceptable to the users. 
       OBJECTS OF THE PRESENT INVENTION 
       [0028]    It is an object of the present invention to overcome, or at least ameliorate, one or more problems with the prior art devices. 
         [0029]    Other preferred objects of the present invention will become apparent from the following description. 
       SUMMARY OF THE PRESENT INVENTION 
       [0030]    In one aspect, the present invention resides in an apparatus for converting a liquid into a semi-frozen or frozen form, including: 
         [0031]    an outer wall and an inner wall sealably connected together to form a refrigerant cavity; 
         [0032]    a refrigerant material at least partially filling the refrigerant cavity, the refrigerant material being able to be cooled below a freezing temperature of the liquid to at least partially-freeze the liquid to form a semi-frozen slurry and/or frozen particles when the liquid is brought into contact with the inner wall; wherein: 
         [0033]    the inner wall is formed from a flexible liner and defines a freezing cavity for the liquid; and 
         [0034]    the outer wall has a base portion flexibly connected to a main body portion; 
         [0035]    so arranged that, before the refrigerant material is cooled, the base portion is moved to a first position adjacent, or at least partially within, the main body portion, and after the liquid is at least partially-frozen, the base portion is moved to a second position at or below the main body portion to cause internal pressure in the refrigerant cavity to move the inner wall towards the main body portion of the outer wall. 
         [0036]    Preferably, the outer wall is formed of a flexible, insulating material; and 
         [0037]    the base portion and main body portion are interconnected by a foldable connection portion, and are preferably formed integrally. 
         [0038]    In one preferred embodiment, a link member interconnects the base portion to a lower portion of the inner wall. 
         [0039]    Preferably, the refrigerant material occupies at least 80% of the volume of the refrigerant cavity when the base portion is in the first position, and is in contact with substantially 100% of the inner wall within the refrigerant cavity when the base position is in the second position. 
         [0040]    In a second aspect, the present invention resides in a method of converting a liquid into a semi-frozen or frozen form, including the steps of: 
         [0041]    cooling a refrigerant material in a refrigerator or freezer, the refrigerant material being contained in a sealed refrigerant cavity between an outer wall and a flexible inner wall of an apparatus, where a base portion of the outer wall occupies a first position and causes the inner wall to move inwardly away from the outer wall; 
         [0042]    removing the apparatus from the refrigerator or freezer; 
         [0043]    placing the liquid within a freezing cavity defined by the inner wall; and when the liquid is semi-frozen or frozen, moving the base portion to a second position away from the inner wall to cause internal pressure in the refrigerant cavity to move the inner wall outwardly towards a main body portion of the outer wall. 
         [0044]    In a third aspect, the present invention resides in a method of converting a liquid into a semi-frozen or frozen form, including the steps of: 
         [0045]    cooling a refrigerant material and the liquid in a refrigerator or freezer, the refrigerant material being contained in a sealed refrigerant cavity between an outer wall and a flexible inner wall of an apparatus, and the liquid being contained in a freezing cavity defined by the inner wall, where a base portion of the outer wall occupies a first position and causes the inner wall to move inwardly away from the outer wall; 
         [0046]    removing the apparatus from the refrigerator or freezer when the liquid is semi-frozen or frozen; and 
         [0047]    moving the base portion to a second position away from the inner wall to cause internal pressure in the refrigerant cavity to move the inner wall outwardly towards a main body portion of the outer wall. 
         [0048]    In a fourth aspect, the present invention resides in a sealing assembly for an apparatus for converting a liquid into a semi-frozen or frozen form, the apparatus having an outer wall and an inner wall forming a refrigerant cavity, and each wall has an inwardly-directed peripheral flange about a respective mouth portion; 
         [0049]    the sealing assembly including: 
         [0050]    an inner locking ring having a tubular body with an outwardly-directed peripheral flange, the tubular body having at least one outwardly-directed locking formation; and 
         [0051]    an outer locking ring having a body with an inner annular wall connected to an outer annular wall by a web member, the inner annular wall having at least one inwardly-directed locking formation complementary with the outwardly-directed locking formation, and the outer annular wall having a downwardly-directed rim; 
         [0052]    so arranged that: 
         [0053]    when the inner wall is located within the outer wall with their respective peripheral flanges co-axially aligned, and the peripheral flange of the inner locking ring wall is aligned with the rim, locking engagement of the inwardly- and-outwardly directed locking formations causes the peripheral flanges of the inner and outer walls to be sealably clamped between the peripheral flange of the inner locking ring and the rim of the outer locking ring. 
         [0054]    Preferably, both the inner and outer walls have lip flanges about their peripheral flanges; and 
         [0055]    the lip flanges are sealably received within the body of the outer locking ring. 
         [0056]    In a fifth aspect, the present invention resides in a sealing assembly for an apparatus for converting a liquid into a semi-frozen or frozen form, the apparatus having an outer wall and an inner wall forming a refrigerant cavity, and each wall has an outwardly-directed peripheral flange about a respective mouth portion; 
         [0057]    the sealing assembly including: 
         [0058]    a top locking ring having an annular wall with an outer peripheral flange with at least one inwardly-directed locking formation; and 
         [0059]    a bottom locking ring having an annular wall having an upper portion with a rim to be received within the outer peripheral flange, the annular wall having at least one outwardly-directed locking formation complementary to the inwardly-directed locking formation; 
         [0060]    so arranged that: 
         [0061]    when the inner wall is located within the outer wall with their respective peripheral flanges co-axially aligned, and the peripheral flange of the outer wall is engaged with the rim, locking engagement of the inwardly- and-outwardly directed locking formations causes the peripheral flanges of the inner and outer walls to be sealably clamped between the annular wall of the top locking ring and the rim of the bottom locking ring. 
         [0062]    Preferably, the annular wall of the lower locking ring has an annular recess; 
         [0063]    both the inner and outer walls have lip flanges about their peripheral flanges; and 
         [0064]    the lip flanges are sealably received in the annular recess. 
         [0065]    Preferably, the top locking ring further includes an inner peripheral flange, on an opposed side of the annular wall. 
         [0066]    Preferably, the inner peripheral flange forms a lower portion of a removable cover for the apparatus, or has at least outwardly-directed locking formation for releasable engagement with a removable cover for the apparatus. 
         [0067]    Preferably, the locking formations comprise one or more screw-threads; but may comprise bayonet coupling members or like releasable formations. 
         [0068]    A flexible wall may overlie the mouth portions of the inner and outer walls and be darned between the annular wall of the top locking ring and the peripheral flange of the inner wall. 
         [0069]    Preferably, the apparatus of the first aspect and/or apparatus incorporating the sealing assembly of the fourth or fifth aspects are received, and preferably enclosed, in a cover formed of semi-rigid or soft materials. 
         [0070]    In a sixth aspect, the present invention resides in an apparatus for converting a liquid into a semi-frozen or frozen form, including: 
         [0071]    an outer wall and an inner wall sealably connected together to form a plurality of refrigerant cavities; and 
         [0072]    a refrigerant material at least partially filling each one of the refrigerant cavities, the refrigerant material being able to be cooled below a freezing temperature of the liquid to at least partially-freeze the liquid to form a semi-frozen slurry and/or frozen particles when the liquid is brought into contact with the inner wall. 
     
    
     
       DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
         [0073]    To enable the invention to be fully understood, preferred embodiments of the present invention will now be described with reference to the accompanying drawings, in which: 
           [0074]      FIGS. 1 to 4  are respective perspective, first side, second side and bottom views of a first embodiment of a beverage freezing device in accordance with the present invention; 
           [0075]      FIG. 5  is a sectional side view of the device of  FIGS. 1 to 4 ; 
           [0076]      FIGS. 6 to 9  are respective perspective, first side, second side and bottom views of a second embodiment of a beverage freezing device in accordance with the present invention; 
           [0077]      FIG. 10  is a sectional side view, with the base portion of the outer wall in the first (or raised) position; 
           [0078]      FIG. 11  is a similar view, with the base portion in the second (or lowered) position; 
           [0079]      FIGS. 12 to 14  are respective side, top and part sectional side views of a third embodiment of a beverage freezing device in accordance with the present invention; 
           [0080]      FIG. 15  is a sectional side view of a fourth embodiment of a beverage freezing device in accordance with the present invention; 
           [0081]      FIG. 16  is a perspective view of a first embodiment of a sealing assembly for a beverage freezing device, as used in the devices of the first, third and fourth embodiments, together with a cover; 
           [0082]      FIG. 17  is a sectional side view of the sealing assembly and cover of  FIG. 16 ; 
           [0083]      FIG. 18  is a perspective view of the locking rings of a second embodiment of a sealing assembly for a beverage freezing device, as used in the device of the second embodiment; 
           [0084]      FIG. 19  is a perspective view of a refrigerant stirring spoon for use with the beverage freezing devices; 
           [0085]      FIG. 20  is a perspective view of a beverage freezing device within a soft-fabric cover; 
           [0086]      FIG. 21  is a perspective view of three ball-type soft-fabric covers; 
           [0087]      FIG. 22  is a perspective view of the two halves of a semi-rigid material cover, with a beverage freezing device received in one half of the cover; 
           [0088]      FIG. 23  is a perspective view of the cover of  FIG. 23  when closed; 
           [0089]      FIGS. 24 and 25  are respective top and side perspective views of a fifth embodiment of a beverage freezing device in accordance with the present invention; and 
           [0090]      FIG. 26  is a perspective view of the device of  FIGS. 24 and 25  containing a semi-frozen liquid. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0091]    Referring to  FIGS. 1 to 5 , the respective components of the beverage freezing device  10  of the first embodiment are manufactured from food-grade polymeric materials, such as silicone rubber and polyethylene. 
         [0092]    The device  10  has an outer wall  11  and an inner wall  12  which are sealed together, as will be hereinafter described, to form a refrigerant cavity  13  containing a refrigerant material  14  e.g. a brine solution. 
         [0093]    The inner wall  12  is formed as a thin, flexible liner, with a convergent side wall portion  15 , a bottom wall portion  16 , and a mouth  17 . 
         [0094]    The outer wall  11  is formed of thicker, insulating material, and has a (downwardly-convergent) main body portion  18  and a base portion  19  interconnected by a connecting portion  20 . The connecting portion  20  has an intermediate portion  21  connected to the main body portion  18  and base portion  19  by respective circumferential fold lines  22 ,  23 . The main body portion  18 , base portion  19  and connecting portion  20  are formed as an integral unit. The outer wall has a mouth  24 . 
         [0095]    As will be hereinafter described in more detail with respect to  FIGS. 16 and 17 , the respective mouths  17 ,  24  of the inner and outer walls  12 ,  11 , are sealed together by a first sealing assembly  40  of the present invention and selectively closed by a removable cover  41 . 
         [0096]      FIGS. 6 to 11  illustrate a second embodiment of a beverage freezing device  110  in accordance with the present invention. The general method of construction is similar to that of the first embodiment of  FIGS. 1 to 5 , except the respective mouths  117 ,  124  of the inner and outer walls  112 ,  111  are sealed together by a second sealing assembly  140  of the present invention, to be hereinafter described with reference to  FIGS. 10 ,  11  and  18 . The removable cover  141  has a hole  142  (which may be offset) to enable access to the frozen beverage in the device  110   
         [0097]    The bottom wall portion  116  of the inner wall  112  is connected to the base portion  119  of the outer wall  111  by a flexible link  125 , so that when the base portion  119  is moved from the first (or raised) position illustrated in  FIG. 10  to the second (or lowered) position illustrated in  FIG. 11 , the bottom wall portion  116  is pulled downwardly therewith. 
         [0098]    The liquid refrigerant material  114  in the refrigerant cavity  113  tends to force the inner wall inwardly, away from the outer wall  111 , when the base portion  119  is moved to the first position. The volume of the refrigerant material  114  is at least 80%, preferably 85%+ of the volume of the refrigerant cavity  113  (but the volume of the refrigerant material, whether liquid or frozen, must not exceed the volume of the refrigerant cavity  113 . 
         [0099]    When the base portions  19 ,  119  are moved to their respective second positions—see FIGS.  5  and  11 —the refrigerant material  13 ,  113  is brought into contact with substantially 100% of the side wall portion  15 ,  115  within the refrigerant cavity  13 ,  113 , the internal pressure (or more correctly, vacuum) in the refrigerant cavity  13 ,  113  drawing the side wall portions  16 ,  116  of the inner wall  12 ,  112  outwardly towards the outer wall  11 ,  111 . 
         [0100]    In addition, when the base portions  19 ,  119  are in their second positions, the inner wall  12 ,  112  does not constrict access to the frozen beverage and makes cleaning of the device  10 ,  110  after use much easier. 
         [0101]    The skilled addressee will appreciate that the device  10 ,  110  may be placed in a refrigerator or freezer to cool the refrigerant material, where the liquid is added after removal therefrom; or the liquid may be placed in the device  10 ,  110  before being placed in the refrigerator or freezer. In either case, on removal from the refrigerator or freezer, the consumer squeezes and/or shakes the device  10 ,  110  to produce a non-solid frozen beverage, and the base portion  19 ,  119  is moved to the second position to both maintain transfer of the cold from the inner wall  12 ,  112  to the frozen beverage and to improve access to the latter. 
         [0102]      FIGS. 12 to 14  illustrate a third embodiment, where the device  210  has an elliptical, or football, shape and has a construction similar to the device  10  of  FIGS. 1 to 5 , except that the outer wall  211  is at least semi-rigid and the device  210  is shaken after the liquid has been placed in the freezing cavity  239  defined by the inner wall  212  and the cover  241 . 
         [0103]    In the device  210 , the outer and inner walls  211 ,  212  are sealed together to form the refrigerant cavity  214  by the first sealing assembly  240  to be hereinafter described. 
         [0104]    The device  310  illustrated in  FIG. 15  is of similar construction to the device  10 , having a substantially “spherical” ball shape, where the inner and outer walls  312 ,  311  may be interconnected by a flexible link  325  to enable the inner wall  312  to be moved outwardly under the internal pressure in the refrigerant cavity  313  in the manner hereinbefore described. 
         [0105]    Alternatively, the outer wall  311  may be semi-rigid and the device  301  is shaken after the device  310  has been removed from the refrigerator or freezer and the liquid added to the freezing cavity  339 . 
         [0106]    The device  310  incorporates a first sealing assembly  340  to now be described in more detail with reference to  FIGS. 16 and 17 . 
         [0107]    The device  310  has inner and outer walls  312 ,  311 , and a removable cover  341 . The mouth  324  of the outer wall  311  is defined by an inwardly-directed peripheral flange  360  and an upwardly-directed lip flange  361 . The mouth  317  of the inner wall  312  is also defined by an inwardly-directed peripheral flange  362  and an inverted-L shape lip flange  363  which forms a downwardly-directed annular sealing recess  364 . 
         [0108]    An inner locking ring  370  has a tubular body  371  with external locking formations in the form of screw-threads  372 . An integral peripheral flange  373  is provided around the lower end of the tubular body  371 . 
         [0109]    An outer locking ring  374  has an annular body  375  of substantially-inverted-U shape, with inner and outer body walls  376 ,  377  interconnected by a web member  378 . NB: The annular body  375 , in this embodiment, has an inclined extension  379  which fills the gap between the cover  341  and the mouth  324  of the outer wall  311 . In the device  10  of the first embodiment, the extension lies parallel to the outer body wall. Inwardly-directed locking formations, in the form of screw-threads  380 , are provided on the inner body wall  376  for releasable (and sealing) engagement with the screw-threads  372 . 
         [0110]    The skilled addressee will appreciate that the lip flange  361  of the outer wall  311  is received within the annular recess  364  of the inner wall  312 , and that the peripheral flanges  360 ,  362  are clamped between the peripheral flange  373  and outer body wall  377  of the inner and outer locking rings  371 ,  374  to provide an effective seal closing the refrigerant cavity  313 . 
         [0111]    The cover  341  has internal screw-threads  343  for sealing engagement with the screw-threads  372  on the inner sealing ring  370 . 
         [0112]    The device  110  incorporates a second sealing assembly  140 , which will now be described with reference to  FIGS. 10 ,  11  and  18 . 
         [0113]    The mouth  124  of the outer wall  111  has an outwardly-directed peripheral flange  160  and a downwardly-directed lip flange  161 . The mouth  117  of the inner wall  112  is defined by similar flanges  162 ,  163 . 
         [0114]    The bottom locking ring  170  has a tubular body with an annular wall  171  with external screw-threads  172 . The top face of the annular wall  171  has an annular recess  173  surrounded by inner and outer circumferential rims  174 ,  175 . 
         [0115]    The top locking ring  176  has a tubular body with an upper annular wall  177  and a lower annular wall  178  (of larger diameter) interconnected by a peripheral flange or web-member  179 . Outwardly-directed screw-threads  180  are provide about the upper annular wall  177 , and inwardly-directed screw-threads  181  are provided on the lower annular wall  178  to engage the screw-threads  172  on the bottom locking ring  170 . The cover  141  has screw-threads  143  to engage the screw-threads  180  to releasably secure the cover  141  to the device  110 . 
         [0116]    The skilled addressee will appreciate that the lip flanges  161 ,  163  of the outer and inner walls  111 ,  112  are received in the annular recess  173 , while the peripheral flanges  160 ,  162  are clamped between the peripheral flange or web-member  179  and the outer circumferential rim  175  of the top and bottom locking rings  176 ,  170  to sealably close the mouths  124 ,  117  of the side walls  111 ,  112 . 
         [0117]    To assist the freezing of the liquid, a spoon  400  may be placed in the device  110 , the spoon having a hollow shaft  401  and concave head  402  filled with a refrigerant material similar the refrigerant material hereinbefore described. The spoon  400  is placed in the refrigerator or freezer with the device; and in the liquid if the device has been filled. After the device has been removed from the refrigerator or freezer, the spoon is inserted into the liquid to assist in freezing the beverage and/or retaining the beverage in an at least semi-frozen state. 
         [0118]    As illustrated in  FIGS. 20 and 21 , the device  10  may be placed in a cavity  501  on a soft-fabric cover  500  and thrown/rolled/shaken/otherwise agitated to agitate the liquid in the device to accelerate the freezing step. As illustrated in  FIG. 21 , the cover  500  may have a range of shapes/ornamentations, including a soccer (football) shape. 
         [0119]    Alternatively, as illustrated in  FIGS. 22 and 23 , the device  10  may be placed in a cavity  601  in one half-body  602  of a semi-rigid material cover  600 . The two half-bodies  602  are secured together by elastic bands (not shown) received in external grooves  603 . 
         [0120]    In a fifth embodiment, the device  710  has an outer wall  711  and an inner wall  712  which are e.g. RF welded together to form a plurality of refrigerant cavities  713 . After being cooled in a refrigerator or freezer, the liquid beverage is converted to an at least semi-frozen beverage  709 , the consumer squeezing the walls  711 ,  712  as the freezing occurs. A tubular extension on the outer wall  711 , above the line of sealing with the inner wall  712 , can provide a folding cover to enclose the liquid and/or frozen beverage  709 . 
         [0121]    Where the device  10 ,  110 ,  210 ,  310  is fitted with a cover  41 ,  141 ,  241 ,  341  having a hole e.g. similar to the hole  142  in cover  141 , a flexible, circular, cover sheet may be clamped over the mouths of the inner walls  12 ,  112 ,  212 ,  312 , by the sealing assemblies  40 ,  140 ,  240 ,  340 , to prevent unwanted loss of liquid from the freezing cavity ( 339 ) in the device  10 ,  110 ,  210 ,  310  while it and the liquid beverage are in the refrigerator or freezer. The sealing assembly may be undone to release the cover sheet, or it may simply be perforated to provide access to the at least semi-frozen beverage for consumption. 
         [0122]    The skilled addressee will appreciate the embodiments of the invention hereinbefore described and illustrated provide simple, efficient, relatively inexpensive, devices and methods for producing at least semi-frozen beverages. 
         [0123]    Various changes and modifications may be made to the embodiments described and illustrated without departing from the present invention.