Making a straw from frozen liquid

Abstract

Apparatus for making a straw of frozen liquid, comprising: a tubular outer member 12 and a tubular inner member 14. The outer member 12 has a closed first end 12a and an open second end 12b. The inner member 14 has an open first end 14a and a closed second end 14b. The inner member 14 is locatable in the outer member 12 such that the first end 14a of the inner member is located against the first end 12b of the outer member 12. Liquid for freezing to form the straw is locatable between the inner member 14 and the outer member 12. The inner member 14 is arranged so a portion 20 thereof, including the second end 14b of the inner member, projects from the outer member when the first end of the inner member is located against the first end of the outer member. The portion 20 is squeezable for increasing air pressure in the inner member to push the inner member away from the first end of the outer member.

Description

06 09 23 Field of the Invention 5 The invention relates to apparatus for making straw from frozen liquid. The invention also relates to an assembly made from the apparatus, and to a method of making a straw from frozen liquid. Background 10 Most straws used today are single-use and formed of plastic. Their use thus results in waste. Straws made from ice are known. Such straws advantageously do not create waste. They also cool drink passing through them. However, difficulty exists in making of straws of ice, particularly in providing a passage through the straw through which drink is to be sucked up. 15 A mould can be used to form the passage, but it is difficult to remove the mould, particularly without breaking the straw. Summary of the Invention 20 According to a first aspect of the invention, there is provided apparatus as defined in claim 1. According to a second aspect, there is provided an assembly as defined in claim 9. According to a third aspect, there is provided a method as defined in claim 11. 25 Optional and / or preferred features and / or steps for each aspect are set out in the claims. Brief Description of Figures 30 Embodiments of the invention are now described, by way of example only, with reference to the accompanying Figures in which: Figure 1A is a perspective view of an assembly according to an embodiment; 35 Figure 1B is a see-through view of the assembly showing different parts; Figure 2 is a side view of an outer tube; Figure 3 is a side view of an inner tube; Figure 4 is a side view of a cap. Detailed Description of Embodiments Apparatus for making an ice straw, shown as an assembly 10 in Figures 1A and 1B, comprises an outer tube 12, an inner tube 14 and a cap 16. Referring also to Figure 2, the outer tube 12 is hollow and has a closed first end 12a. Interior and exterior concentric surfaces of the outer tube 12 are cylindrical. The outer tube 12 is open at its second end 12b. The first end 12a has a domed shape with a base portion 22 at a centre thereof. Referring also to Figure 3, the inner tube 14 has an open first end 14a and closed second end 14b. An exterior surface of the inner tube 14 is cylindrical. An interior surface of the inner tube 14 is also cylindrical. The inner tube 14 is shaped to fit in the outer tube 12 with a first end 14a of the inner tube 14 located against the base portion 22. When the first end 14a is so located, a portion 20 of the inner tube 14, which includes the second end 14b, projects from the second end 12b of the outer tube 12. The interior surface of the outer tube 12 and the exterior surface of the inner tube 14 have relative diameters so that liquid can be located between the two surfaces. They provide a mould to form a straw. The base portion 22 is circular and serves to centre the first end 14a of the inner tube 14. Although not essential, preferably the first end 14a of the inner tube 14 fits against first end 16a in a sealing manner, to prevent egress of air within the inner tube 14 and prevent ingress of liquid. Referring also to Figure 4, the cap 16 is configured for mounting on the second end 12b of the outer tube 12. The cap 16 has an aperture 18 therethrough. The inner tube 14 extends through the aperture 18, such that a portion 20 of the inner tube 14 projects from the cap 16 and also from the second end 12b of the outer tube 12. The portion 20 is squeezable by a user to increase air pressure in the inner tube 14. The aperture 18 is located in a centre of the cap 16, so that the cap 16 retains the inner tube 14 concentrically with respect to the second end 16a of the outer tube 16. The aperture 18 together with the base portion 22 result in the inner tube 14 being retained concentrically within the outer tube 12. The cap 16 and an exterior of the second end 12b of the outer tube are respectively shaped so that the cap 16 can be located fittingly over the second end 12b, this and the nature of the material from which the cap 16 and the outer tube 12 are made permitting the cap 16 to stay in place. The outer tube 12, the inner tube 14 and the 16 are made from silicone. Embodiments are not limited to being made from silicone; one, more or all may be made from alternative resiliently deformable materials. In use, first the inner tube 14 is inserted by the user into the outer tube 12 so the first end 14a is located against the base portion 22. A user then fills the outer tube 12 with liquid to be frozen. Alternatively, the inner tube 14 can be inserted after the outer tube 12 has been filled. The cap 16 is then mounted on the second end 12b of the outer tube 12 with the inner tube 14 being located through the aperture 18. The assembled parts with the contained liquid in are then put in a freezer until the liquid is frozen. Preferably, the assembled parts are put in the freezer in an upright position. This is because, if the outer tube 12 has not been completely filled with the liquid, air will be present. Positioning the assembly 10 upright causes the air to rise to a top of the assembly 10. If air is present and the assembly 10 is positioned on its side, a thin section of a wall of the straw will result. After the liquid is frozen, the assembly 10 is removed from the freezer. Due to expansion of the liquid, air in the inner tube 14 is pressurised. The portion 20 is then squeezed by the user, further pressurising air in the inner tube 14. The pressure in the inner tube 14 at the first end 14a pushes apart the inner tube 14 and the base portion 22, decoupling the inner tube 14 from the frozen liquid surrounding it. The inner tube 14 can them be easily pulled out of the outer tube 12 by the user through the aperture 18. The user then removes the cap 16. Alternatively, the cap 16 can be removed with the inner tube 14. The outer tube 12 must then be removed from the straw. This is done first by warming the outer tube 12, typically using hands. Alternatively, the outer tube with its frozen contents can just be left for a few minutes. Then, the user squeezes the first end 12a of the outer tube 12, incrementally pushing the straw out of the outer tube 12 by repeated squeeze actions up the outer tube 12 from the first end 12a to the second end 12b. The straw can then be put directly into a drink or glass, or returned to a freezer future use. Embodiments are not limited to use of any particular liquid, provided the liquid can be frozen and safely used as a drinking straw. The liquid is typically water or water-based, and may also be flavoured. Embodiments are not limited to the interior surface of the outer tube 12 and the exterior surface of the inner tube 14 each being cylindrical. Alternatively, they may each have square cross sections for example. The relative shapes of the outer tube 12 and the inner tube 14 may be modified, provided the inner tube 14 can be inserted into the outer tube 12 and provided they are then spaced such that a wall of the resultant straw has a thickness to be able to survive use. Embodiments are not limited to the first end 12a of the outer tube having a domed shape with the base portion 22. The shape may be in the form of a frustum of another type causing centring of the inner tube 14. Alternative means for centring may also be provided; for example, a projection may be provided from the first end 12a of the outer tube 12 inwardly, which can extend into the first end 14a of the inner tube 14. In variant embodiments, the cap 16 may be absent. Alternative means may be provided to centre the inner tube 14 with respect to the second end 12b the outer tube 12. For example, the inner tube 12 may have arms projecting radially for location against an inner surface of the outer tube 12 at the second end 12b of the outer tube 12. The outer tube 12 would be filled with liquid to be frozen such that such arms, being at a top of the outer tube 12 when the outer tube 12 is upright, are clear of the liquid and do not impede the inner tube 14 being removed after freezing of the liquid. By way of other example, a frame may be provided, mounting on an exterior of the outer tube 12, for retaining the inner tube 14 centred with respect to the outer tube 12. Unless otherwise indicated, all individual features and / or steps of all embodiments described herein are disclosed in isolation and any combination of two or more such features is also disclosed, to the extent that such features or steps or combinations of features and / or steps are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art. This is regardless of whether such features or steps or combinations of features and / or steps solve any problems disclosed herein.

Claims

1. Apparatus for making a straw of frozen liquid, comprising:a tubular outer member having a closed first end and an open second end;a tubular inner member having an open first end and a closed second end,wherein the inner member is locatable in the outer member such that the first end of the inner member is located against the first end of the outer member,wherein liquid for freezing to form the straw is locatable between the inner member and the outer member,wherein the inner member is arranged so a portion thereof, including the second end of the inner member, projects from the outer member when the first end of the inner member is located against the first end of the outer member, andwherein the portion is squeezable for increasing pressure in the inner member to push the inner member away from the first end of the outer member.2 The apparatus of claim 1, wherein the inner tube is configured so that, on freezing of the liquid, expansion of the liquid against the inner member pressurises air in the inner member.

3. The apparatus of claim 1 or claim 2, further comprising means for centring the inner member in the outer member.

4. The apparatus of claim 3, wherein the centring means comprises first means for centring the first end of the inner member in the outer member, wherein the first end of the outer member includes the first means for centring.

5. The apparatus of claim 3 or claim 4, wherein the centring means comprises second means for centring the inner member in the outer member at the second end of the outer member.

6. The apparatus of claim 5, wherein the second centring means comprises a cap for mounting on the second end of the outer member, wherein the cap has an aperture therethrough through which the inner member extends and from which the portion projects.

7. The apparatus of claim 6, wherein the cap, together with the inner tube extendingtherethrough, is for sealing the second end of the tubular member.

8. The apparatus of any one of the preceding claims, wherein the inner member is locatable in the outer member such that the first end of the inner member is located against the first end of the outer member to seal the interior of the inner member.

9. An assembly comprising the apparatus of any one of the preceding claims, wherein the inner member is inserted in the outer member with the portion of the inner tube projecting from the second end of the outer member.

10. The assembly of claim 9 when comprising the apparatus of any one of claims 6 to 8, wherein the cap is mounted on the second end of the outer member and the inner member extends through the aperture.

11. A method of making a straw of frozen liquid, comprising:providing a tubular outer member having a closed first end and an open second end with an inserted tubular inner member having an open first end and a closed second end with the first end of the inner member located against the first end of the outer member and a portion of the inner member projecting from the second end of the outer member, and with liquid to be frozen between the inner and outer members;after freezing of the liquid, squeezing the portion to increase pressure in the inner member, to push the inner member away from the first end of the outer member and thus decouple the inner member from the straw.

12. The method of claim 11, wherein the providing the outer member with an inserted inner member with the first end of the inner member located against the first end of the outer member comprises locating the first end of the inner member against a means for centring the in the first end of the outer member.

13. The method of claim 11 or claim 12, further comprising mounting a cap on the outer member with the inner member extending through an aperture in the cap, such that the portion projects from the aperture.

14. The method of claim 13, wherein the cap, together with the inner tube extending therethrough, is for sealing the second end of the tubular member.

15. The method of claim 13 or claim 14, wherein the cap retains the inner member in a centre of the outer member.

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