GB2097653A - Insulated containers for dispensing liquids - Google Patents

Abstract

An insulated container such as a teapot for dispensing hot or cold liquids comprises double walls (12,22) moulded in two wall moulding stages in ceramic ware and an insulating material such as low density rigid foam 36 located between the double walls. <IMAGE>

Description

SPECIFICATION Liquid dispensing apparatus and method of manufacturing same This invention relates to a liquid dispensing apparatus and a method of manufacturing same, and is particularly concerned with small domestic containers such as teapots and coffee-pots.

According to the present invention there is provided a liquid dispensing apparatus comprising a body having a first wall defining a cavity for containment of a liquid, a second wall extending around the first wall and spaced outwardly there- from at at least predetermined locations, and heat insulating means provided between said first and second walls.

Preferably said first and second walls are formed of a ceramic material, and the body is formed as an integral moulded component.

Preferably also said first wall defines a spout through which liquid can be dispensed from the cavity. A handle may be provided at a location on said second wall generally opposite the location of the spout and may be formed by spaced walls with heat insulating means provided therebetween.

Further the first wall may have an additional opening which is closable by a lid, the latter having a hollow configuration with heat insulating means provided therein.

Advantageously the heat insulating means comprises a low density rigid foam.

According to the present invention there is also provided a method of manufacturing a liquid dispensing apparatus, said method comprising forming a first wall which defines a cavity for containment of a liquid, forming a second wall around and spaced outwardly from said first wall at at least predetermined locations, and locating heat insulating means between said first and second walls.

Preferably the method comprises locating mould parts together to define a first mould, casting slip in the first mould to form the first wall, inverting the first mould with the moulded first wall, removing certain of the mould parts, and replacing with further mould parts spaced from the moulded first wall at said predetermined locations, to define a second mould with the first moulded wall, casting slip in the second mould to define the second wall integral with the first wall, and removing the second mould ports to release the integral moulded apparatus.

Preferably also the cavity defined by the moulded first wall is filled with a moisture absorbing material prior to moulding of the second wall, such that the slip is formed only on the further mould parts and not the first moulded wall. The moisture absorbing material is preferably a material which can be burnt away during subsequent firing of the moulded apparatus, for example sawdust.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawing, the single figure of which is a section through a teapot.

Referring to the drawing, a teapot 10 has a body defined by an integral shell of a ceramic material and comprising an inner wall 12 presenting a cavity 14 for containment of a liquid. The wall 12 is shaped at one location to define a spout 16 through which the liquid can be dispensed, and at its upper end in use the wall 12 presents an opening 18 through which the liquid can enter the teapot 10. The opening 18 is closable by a lid 20 as hereinafter described.

An integral outer wall 22 is generally located around, and spaced from, the sides and lower end of the inner wall 12, with the exception of the location of the spout 16, the latter being formed as a single wall thickness only. At a location on the outer wall 22, generally opposite the spout 16, there is formed a handle 24 which is defined by a pair of spaced walls 26,28 formed integrally with the outer wall 22. The latter is further formed with an integral base part 30 by means of which the teapot 10 can stand.

The lid 20 is moulded from a ceramic material of hollow configuration, presenting a handle part 32 an annular lip 34 for seating on the upper end of the inner wall 12 and a downwardly extending flange 35 for locating in the opening 18.

Within the double walled parts of the body of the teapot 10, there is located a heat insulating material 36, for example a low density rigid foam such as MDI-diphenylmethane diisocyanate. The material 36 also fills the hollow interior of the lid 20.

To manufacture the teapot 10, a plaster of Paris mould is first formed by three mould parts retained together, a top part seated on two side parts of which meet at their lower ends. The top part has two openings through which slip can be poured to form the inner wall 12 on the inner walls of the moulded parts, the openings corresponding to the spout opening and the top opening 18. After casting, the mould is inverted to drain the excess slip and the cavity 14, defined by the inner wall 12, is filled with a flowable, moisture absorbing material, for example sawdust.

With the sawdust retained in thecavity 14, the side parts of the mould are removed after the moulded inner wall 12 has dried to a sufficient extent and replacement side parts are located on the original top part, but now the lower part of the mould. The replacement side parts engage with the moulded spout 16 but are generally otherwise spaced from the moulded wall 12. The new mould is completed by an additional top part mounted on the replacement side parts. Slip is then introduced through suitable holes in the additional top part and, as the mould parts are formed of plaster of Paris which is absorbent, the outer wall 22 is built up on the inner walls of the mould parts, but not the moulded inner wall 12 from which moisture has been removed by the sawdust, excess slip being drained.After suitable drying, the mould parts are removed to release the moulded shell oftheteapot 10.

In subsequent firing of the moulded shell, the sawdust is burnt away and it will be appreciated that any suitable decoration applicable to a ceramic article may be provided.

For insulation purposes, the double walled parts of the moulded shell are filled through the filling holes with a heat insulating material, preferably a low density rigid urethane foam which is initially avail able in a flowable state. One example of the foam is MDI-Diphenylmethane diisocyanate. After injection of the foam, the filling holes are plugged.

The teapot 10 thus formed significantly reduces the rate of cooling of hot liquids such as tea, and also facilitates the handling of the teapot because the outer walls do not heat up to the same extent as conventional teapots. Further, the handle is totally insulated and therefore is not affected by the hot liquid thus facilitating handling of the teapot. It will be appreciated of course that the invention can be applied to other beverages. It will also be appreciated that when used to dispense cooled liquids, the liquids will stay cooler in such a container for a greater length of time than in other containers of a similar type. The shapes of the containers may of course differ greatly from that shown.

Although the invention has been described in relation to a teapot having a moulded integral body, the body may be fabricated by having its inner wall moulded and one or more outer wall pieces fixed on the inner wall.

Various other modifications may be made without departing from the invention. For example other types of heat insulating material may be used and also other types of filling for the internal cavity during moulding may be provided. Sawdust is particularly suitable however as not only is it flowable and hygroscopic but it will burn away on subsequent firing in a ceramic container.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the applicant claims protection in respect of any patentable feature or combination of features herein before referred to whether or not particular emphasis has been placed thereon.

CLAIMS (filed 7.4.82.) 1. Liquid dispensing apparatus comprising a body having a first wall defining a cavity for containment of a liquid, a second wall extending around the first wall and spaced outwardly therefrom at at least predetermined locations, and heat insulating means provided between said first and second walls.

2. Liquid dispensing apparatus as claimed in claim 1 wherein said first and second walls are formed of a ceramic material, and the body is formed as an integral moulded component.

3. Liquid dispensing apparatus as claimed in claim 1 or claim 2 wherein said first wall defines a spout through which liquid can be dispensed from the cavity.

4. Liquid dispensing apparatus as claimed in any preceding claim, wherein a handle is provided at a location on said second wall generally opposite the location of the spout and is formed by spaced walls with heat insulating means provided therebetween.

5. Liquid dispensing apparatus as claimed in any preceding claim wherein the first wall has an additional opening which is closable by a lid, the latter having a hollow configuration with heat insulating means provided therein.

6. Liquid dispensing apparatus as claimed in any preceding claim wherein the heat insulating means comprises a low density rigid foam.

7. A method of manufacturing a liquid dispensing apparatus comprising forming a first wall which defines a cavity for containment of a liquid forming a second wall around and spaced outwardly from said first wall at at least predetermined locations, and locating heat insulating means between said first and second walls.

8. A method of manufacturing a liquid dispensing apparatus as claimed in claim 7 wherein the method comprises locating mould parts together to define a first mould, casting slip in the first mould to form the first wall, inverting the first mould with the moulded first wall, removing certain of the mould parts, and replacing with further mould parts spaced from the moulded first wall at said predetermined locations, to define a second mould with the first moulded wall, casting slip in the second mould to define the second wall integral with the first wall, and removing the second mould parts to release the integral moulded apparatus.

9. A method of manufacturing a liquid dispensing apparatus as claimed in claim 7 or claim 8 wherein the cavity defined by the moulded first wall is filled with a moisture absorbing material prior to moulding of the second wall, such that the slip is formed only on the further mould parts and not the first moulded wall.

10. A method of manufacturing a liquid dispensing apparatus as claimed in any of claims 7 to 9 wherein moisture absorbing material is preferably a material which can be burnt away during subse quentfiring of the moulded apparatus.

11. A method of manufacture a liquid dispensing apparatus as claimed in claim 10 wherein the moisture absorbing material is sawdust.

12. Liquid dispensing apparatus substantially as hereinbefore described with reference to the accompanying drawing.

13. A method of making a liquid dispensing apparatus substantially as hereinbefore described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (13)

**WARNING** start of CLMS field may overlap end of DESC **. able in a flowable state. One example of the foam is MDI-Diphenylmethane diisocyanate. After injection of the foam, the filling holes are plugged. The teapot 10 thus formed significantly reduces the rate of cooling of hot liquids such as tea, and also facilitates the handling of the teapot because the outer walls do not heat up to the same extent as conventional teapots. Further, the handle is totally insulated and therefore is not affected by the hot liquid thus facilitating handling of the teapot. It will be appreciated of course that the invention can be applied to other beverages. It will also be appreciated that when used to dispense cooled liquids, the liquids will stay cooler in such a container for a greater length of time than in other containers of a similar type. The shapes of the containers may of course differ greatly from that shown. Although the invention has been described in relation to a teapot having a moulded integral body, the body may be fabricated by having its inner wall moulded and one or more outer wall pieces fixed on the inner wall. Various other modifications may be made without departing from the invention. For example other types of heat insulating material may be used and also other types of filling for the internal cavity during moulding may be provided. Sawdust is particularly suitable however as not only is it flowable and hygroscopic but it will burn away on subsequent firing in a ceramic container. Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the applicant claims protection in respect of any patentable feature or combination of features herein before referred to whether or not particular emphasis has been placed thereon. CLAIMS (filed 7.4.82.)

1. Liquid dispensing apparatus comprising a body having a first wall defining a cavity for containment of a liquid, a second wall extending around the first wall and spaced outwardly therefrom at at least predetermined locations, and heat insulating means provided between said first and second walls.

2. Liquid dispensing apparatus as claimed in claim 1 wherein said first and second walls are formed of a ceramic material, and the body is formed as an integral moulded component.

3. Liquid dispensing apparatus as claimed in claim 1 or claim 2 wherein said first wall defines a spout through which liquid can be dispensed from the cavity.

4. Liquid dispensing apparatus as claimed in any preceding claim, wherein a handle is provided at a location on said second wall generally opposite the location of the spout and is formed by spaced walls with heat insulating means provided therebetween.

5. Liquid dispensing apparatus as claimed in any preceding claim wherein the first wall has an additional opening which is closable by a lid, the latter having a hollow configuration with heat insulating means provided therein.

6. Liquid dispensing apparatus as claimed in any preceding claim wherein the heat insulating means comprises a low density rigid foam.

7. A method of manufacturing a liquid dispensing apparatus comprising forming a first wall which defines a cavity for containment of a liquid forming a second wall around and spaced outwardly from said first wall at at least predetermined locations, and locating heat insulating means between said first and second walls.

8. A method of manufacturing a liquid dispensing apparatus as claimed in claim 7 wherein the method comprises locating mould parts together to define a first mould, casting slip in the first mould to form the first wall, inverting the first mould with the moulded first wall, removing certain of the mould parts, and replacing with further mould parts spaced from the moulded first wall at said predetermined locations, to define a second mould with the first moulded wall, casting slip in the second mould to define the second wall integral with the first wall, and removing the second mould parts to release the integral moulded apparatus.

9. A method of manufacturing a liquid dispensing apparatus as claimed in claim 7 or claim 8 wherein the cavity defined by the moulded first wall is filled with a moisture absorbing material prior to moulding of the second wall, such that the slip is formed only on the further mould parts and not the first moulded wall.

10. A method of manufacturing a liquid dispensing apparatus as claimed in any of claims 7 to 9 wherein moisture absorbing material is preferably a material which can be burnt away during subse quentfiring of the moulded apparatus.

11. A method of manufacture a liquid dispensing apparatus as claimed in claim 10 wherein the moisture absorbing material is sawdust.

12. Liquid dispensing apparatus substantially as hereinbefore described with reference to the accompanying drawing.

13. A method of making a liquid dispensing apparatus substantially as hereinbefore described with reference to the accompanying drawing.