WO2002064447A1

WO2002064447A1 - Heat-insulated container

Info

Publication number: WO2002064447A1
Application number: PCT/FR2002/000530
Authority: WO
Inventors: Albert Benat
Original assignee: Albert Benat
Priority date: 2001-02-13
Filing date: 2002-02-12
Publication date: 2002-08-22
Also published as: FR2820725A1; US20040129711A1; FR2820725B1

Abstract

The invention concerns a heat-insulated container (1), preferably a bottle, flask, can or the like, designed to receive directly a product, preferably a food product such as a beverage, introduced or extracted, through an opening (5) closed with a cap (6), in a chamber (4) delimited by an inner wall (2), said container further comprising an outer wall (3) which, with the inner wall, defines a closed volume (24), the major part of said inner wall (2) having a first high heat conductivity and second low heat conductivity. Said container is characterised in that it comprises intrinsic transformation means and mechanical control means (R) for shifting from said first state to said second state. The invention is applicable to heat insulation of beverages to be consumed hot or cold.

Description

THERMALLY INSULATED CONTAINER

The present invention relates to a thermally self-insulating container, in particular a bottle, a gourd, a can or any similar container, intended to receive a product, preferably a food product, for example a drink.

TECHNOLOGICAL BACKGROUND OF THE INVENTION

The principle of the double wall to limit the heat exchanges between the inside and the outside of a container - or vice versa - has been known for a very long time. The Dewar vase, with two silver inside walls, between which a vacuum has been created, eliminates any possibility of heat transfer by conduction, convection or radiation. This type of container, due to the 19th century English chemist and physicist who gave it its name, is the ancestor of all thermally insulated containers known today as the "thermos bottle".

However, thermos are fragile and therefore, to avoid this drawback, it is common to replace the vacuum between the two walls with a material of low thermal conductivity, in order to improve the robustness of the jacket.

In this regard, as shown in particular by US Pat. No. 2,215,532 issued on September 24, 1940, in the name of E. Richardson, the use of a thermally insulating fluid is not new. The method and the device described also provide a solution to the problem of heating an isolated enclosure, consisting in precisely controlling the convective movements of the fluid in the wall.

The question of allowing, on the one hand, the heat exchanges between the environment and the interior chamber of the container and, on the other hand, the insulation of the latter as required may be of importance, for example in the case of the sale of food drinks to be consumed preferably hot or cold, each at a so-called temperature hereinafter ideal. It is a question of effectively heating - or cooling - the drink to said ideal temperature for consumption in its container, then to maintain it at this ideal desired temperature until the moment of its consumption, said drink then being isolated or, even otherwise said, the container is no longer subjected on this occasion, on the part of its environment, to a heat transfer intended to maintain the drink at the ideal temperature for consumption. For this purpose, the thermal characteristics of the wall of the container can be adapted to the various conditions of use by an appropriate choice of its structure and the nature of the fluid.

For example, French patent application FR-2,306,661 published on November 5, 1976 in the name of M. Brevi describes a cooling glass for beverages, the structure of which is that of a Dewar vase, but in which the vacuum has been replaced with water that can be frozen. According to the inventor, the icicle formed makes it possible to cool the drink contained in the glass, while remaining isolated from room temperature. Japanese patent application JP-10 / 099.213 published on April 21, 1998, in the name of the company Yokoyama, describes a tankard implementing a similar principle. Ice water can be introduced into the double wall, through the removable bottom of the mug, and can be changed on demand. The transition from a state of low thermal conductivity to a state of high conductivity of part of the wall of the container can also be obtained by a simple removal of the insulating material. European patent application EP-0.891.738 published on January 20, 1999, in the name of D. Bengtson, illustrates this type of process: the conductive bottom of the thermos bottle is provided with a removable insulating envelope.

The use of a gas with low thermal conductivity as a fluid has also given rise to a large number of thermal insulation devices.

One of the simplest systems, for example that described in American patent US-5,896,641 published on April 27, 1999, in the name of M. Yamada et al., Comprises a chamber filled with gas, xenon, krypton, or argon, inserted in a double wall. The insulating enclosure can only be a flexible inflatable structure. German patent application DE-3,813,218 published on November 2, 1989, in the name of H&V Konzeption Design Planun, illustrates such a design. The container, intended to keep cold and protect food or drinks, consists of two sheets of flexible material, PVC or other, welded together to form puffy bags by means of a valve. Devices, based on the same principle, use a compressed gas generator to inflate the walls of the container. Japanese patent application JP-5 / 278,765 published on October 26, 1993, in the name of the company Fushimi Jushi, discloses the use of a carbon dioxide cartridge. The phenomenon of liquefaction or vaporization of a fluid at a given temperature has an application in the manufacture of insulating walls at high temperature. Indeed, above its vaporization temperature, the fluid is in the state of gas of low conductivity, while it is liquid below, and therefore better transmits heat. For example, the walls described in Japanese patent application JP-7 / 156.974 published on June 20, 1995, in the name of the company Kukoba, change thermal property between

300 ° C and 400 ° C. In the case of a packaging for food intended to be heated in a microwave oven, as described in American patent US Pat. No. 5,081,330 published on January 14, 1992, in the name of L. Brandberg et al., the expansion of the residual air present between two sheets of material welded along contact lines is enough to create insulating pockets.

All the documents described above describe a process or disclose a device for modifying the state of thermal conductivity of the walls of a container. This modification is obtained either by adding or removing an element from the container, or even by modifying the temperature outside it. However, none of the systems, processes and / or devices contained in the state of the art uses internal means integral with the container to carry out the transformation. In addition, the auto containers Existing insulation does not, in general, provide both a solution to the problem of reheating and to the problem of cooling an insulating container.

It therefore appears from the state of the art that self-insulating receptacles comprising a double wall, the interval of which contains a fluid, and having a double state, insulating or conducting, are known, but that there exists to date no device that exactly meets the needs.

GENERAL DESCRIPTION OF THE INVENTION

The present invention therefore relates to a self-insulating container, preferably of the "bottle", "gourd", "can" or similar type, intended to directly receive a product, preferably a food product such as a drink, introduced or extracts, by means of an opening closed by a plug, in an enclosure delimited by an internal wall, said container further comprising an external wall which, with the internal wall, delimits a closed chamber, most of the internal wall having a first state of high thermal conductivity and a second state of low thermal conductivity, said container being characterized in that it comprises transformation means, which are intrinsic to it, and mechanical control means for effecting the passage from said first state to said second state, in that, in the first state, the chamber delimited by the double wall comprises a thermally conductive liquid ur filling at least the part of said chamber which is located in line with the enclosure and in that, in the second state, the chamber delimited by the double wall comprises a thermally insulating gas filling at least the part of said chamber which is located to the right of the enclosure.

Advantageously, the thermally conductive liquid and the thermally insulating gas present in the double wall are preferably water and, respectively, air. According to two first alternative embodiments, the self-insulating container according to the invention is characterized in that the chamber delimited by the double wall: a) contains a first fluid of high thermal conductivity and a second fluid of low thermal conductivity, said first and second fluids being of different densities and immiscible with each other, b) has an asymmetry such that, in a first position of the container corresponding to the first state, most of the internal wall is wetted by the first fluid and, in a second position of the container corresponding to the second state, the major part of said internal wall is wetted by the second fluid.

In a first alternative embodiment, the self-insulating container according to the invention is characterized in that the asymmetry results from a space, comprised between the part of the external wall constituting the bottom of said container and the part of the wall internal facing this bottom, the volume of said space being greater than 50% of the total volume of the chamber delimited by the double wall.

Still in this first alternative embodiment, the container according to the invention is preferably such that: a) the first fluid is a liquid with high thermal conductivity, preferably water, and the second fluid is a gas with low thermal conductivity , preferably air, b) the first position of the container corresponding to its first state is a first vertical position, the opening or neck being directed downwards, and the second position of the container corresponding to its second state is a second vertical position in which the opening or neck faces upwards.

In a second variant embodiment, the self-insulating container according to the invention is characterized in that the asymmetry results from a thickness of the chamber delimited by the double wall which is greater at part of the internal wall constituting a side of the container than it is at the diametrically opposite part of the inner wall.

Still in this second variant embodiment, the container according to the invention is preferably such that: a) the first fluid is a liquid with high thermal conductivity, preferably water, and the second fluid is a gas with low thermal conductivity , preferably air, b) the first position of the container corresponding to its first state is a first horizontal position in which the part of the chamber delimited by the double wall having the greatest thickness is located above the container, and the second position of the container corresponding to its second state is a second horizontal position in which the part of the chamber delimited by the double wall having the greatest thickness is located below said container.

According to a third alternative embodiment, the self-insulating container according to the invention is characterized in that the processing means comprise a frangible membrane placed between the part of the external wall constituting the bottom of the container and the part of the internal wall. facing this bottom, and intended to release by gravity the overlying thermally conductive liquid, as well as a thermally insulating gas, preferably air, filling the space between said membrane and the part of the outer wall constituting the bottom of the container.

In this third variant, the control means with which the container according to the invention is provided preferably comprises means for breaking, preferably by impact or pressure, the membrane.

Advantageously, in all the variants envisaged, the double wall of the container according to the invention is made of plastic or aluminum or any other material compatible with the product to be thermally insulated.

Also preferably, and always in all the variants envisaged, the container according to the invention is such that its first and second fluids are introduced permanently in the chamber delimited by the double wall at the time of manufacture of said container.

BRIEF DESCRIPTION OF THE DRAWINGS

Figures la and lb are schematic sectional views of a first embodiment of the self-insulating container according to the invention, the wall of which is respectively in a state of high thermal conductivity, and in a state of low conductivity thermal after inverting the container in a vertical plane.

Figures 2a and 2b are schematic sectional views of a second embodiment of the self-insulating container according to the invention, the wall of which is respectively in a state of high thermal conductivity, and in a state of low conductivity thermal after rotating the container half a turn horizontally.

Figures 3a and 3b are schematic sectional views of a third embodiment of the thermally self-insulating container according to the invention, the wall of which is respectively in a state of high thermal conductivity, and in a state of low thermal conductivity after rupture of an internal membrane.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

The present invention consists of a container (1) with double wall, each of said walls (2,3) being sealed. The internal wall (2) delimits a closed interior enclosure (4), intended to receive a product, preferably a food product, which for the rest of the description will be defined by way of example under the term "drink". The upper part of this internal wall (2), which is either flat if the container is of the "can" type, or in the form of a neck if the container is of the "bottle" or "gourd" type, as shown by example in the drawings, comprises an opening (5) which is closed by a stopper (6) and by which the drink is introduced into the enclosure (4). The outer wall (3) is connected to this inner wall (2) at the opening (5) or slightly below. The connection line between the two walls, internal (2) and external (3) respectively, is itself sealed. The walls (2, 3) therefore delimit between them a chamber (24) which is itself closed.

The particular shape and position of the inner enclosure (4) relative to the outer wall (3) make it possible to transform a thermally conductive container into a heat insulating container by a simple change of position thereof. .

A first preferred embodiment of the container is shown schematically in Figures la and lb. In this first embodiment, the walls (2) and (3) are separated from each other by an interval (A) which is constant at the sides of the container, but it is intended that a wider distance (B) than the above-mentioned interval (A), visible in FIGS. 1a and 1b, separates the bottoms (22, 23) from the internal (2) and respectively external (3) walls. (It should be noted here that, for a better understanding of the drawings of FIGS. 1a and 1b, the interval (A) separating the walls (2) and (3) has been voluntarily enlarged).

This wider distance (B) is moreover such that the volume of the space (11) located between the two bottoms (22, 23) is greater than 50% of the total volume of the chamber (24) delimited by the two walls (2, 3).

In Figure la, the container (1) is shown with its opening (5), here its neck, directed downwards. In this position, the double wall (2,3) is partially filled with a liquid with high thermal conductivity (9) which has been introduced inside the chamber (24) delimited by the walls (2, 3), up to 'to come at least by covering the bottom (22) of the internal wall (2). The wall (2) at the level of the neck and the sides of the enclosure (4) will therefore allow heat transfers with the outside in order to heat, cool, or maintain at an adequate temperature, namely the ideal consumption temperature, the drink contained in the enclosure (4) of the container (1).

Advantageously, the volume of the thermally conductive liquid (9) occupies less than 50% of the total volume of the chamber (24), and preferably a volume slightly less than 50% of the aforementioned total volume.

Above the bottom (22) of the inner enclosure (4), there therefore remains in the chamber (24) delimited by the two walls (2,3) a space (11) empty of liquid and filled with gas ( 10) insulator, which itself therefore occupies a volume greater than 50% of the total volume of said chamber (24), and therefore greater than the volume of the thermally conductive liquid (9). Thus, the space (11) has a sufficient volume to collect at least all of the liquid (9) contained in the double wall (2,3) when the container (1) is turned over (R) vertically in normal position with its neck (5) facing upwards. This position is shown in Figure lb. After such a reversal, the inner enclosure (4) is then entirely surrounded by the gas (10) and the heat exchanges with the environment are considerably limited.

The gas (10) and the liquid (9) used are preferably air and respectively water. Air is indeed a fairly good thermal insulator, because it has a coefficient of thermal conductivity of the order of 0.025 / m ° K, while that of water is about 20 times greater.

A simple calculation allows to estimate the thickness that must be given to the air layer (above the interval (A) separating the walls (2, 3) at the sides of the container) to maintain for a duration D of a cylindrical container containing water below a certain temperature Tl, the container having been cooled to temperature T0 and the ambient temperature being Tamb, taking into account only the heat exchanges by the surface side of the container (1) and neglecting convection and radiation exchanges.

For an initial temperature T0 = 5 ° C and a hold below T1 = 10 ° C, the results are as follows (thickness or interval (A) in mm) in the case of a cylinder having a diameter of 90 mm ( size of a standard 1.5 L bottle of mineral water):

The thickness (A) to be given to the double wall (2, 3) being known, it is easy to deduce in the case of a cylindrical container with a volume of 1.5 L the minimum height (B ) of the space (11) intended to receive the thermally conductive liquid after the reversal (R). An elementary calculation shows that the relative increase in height of the external wall (3) must be substantially equal to twice the relative increase in the radius of the internal wall (2), i.e. the relative thickness of the double wall (2,3). Under the same temperature conditions as above, the minimum additional height (B) to be expected approximately (in mm) is:

These results show that, by means of an outer wall (3) of dimensions slightly larger than those of the non-insulated container, the drink contained in the enclosure (4) remains fresh for an appreciable time even if the ambient temperature is high.

The effect of the insulation is of course the same whether it is a hot drink or a cold drink. Thanks to the remarkable simplicity of the device, it will even be possible for the trader to present the container according to the invention in a normal position to his client so that the container nevertheless retains an optimum temperature for a long time. In the second embodiment of the self-insulating container according to the invention, shown diagrammatically in FIGS. 2a and 2b, the principle of creating an asymmetry in the internal volume of the double wall (2,3) is also implemented . The asymmetry is in this case axial, two diametrically opposite side parts of the double wall (2,3) having a different thickness.

As the asymmetry is axial, the container must be laid down so that it generates a variation in the position of the liquid (9) in the double wall (2,3) when the container (1) is turned on itself, half a turn (R).

When the part having the smallest thickness is below the container, as shown in FIG. 2a, the liquid (9) of a given volume, this time again less than 50% of the total volume of the chamber (24), must cover a large area. Much, if not all, of the inner enclosure (4) is therefore surrounded by a wall (2) with high thermal conductivity. It is the opposite, when the thickest part (11) is below the container (1), as shown in Figure 2b: this part (11) collects the liquid (9), and the gas (10) therefore isolates the enclosure (4).

The transition from the most conducting state to the most insulating state is here again carried out manually by a rotation

(R) 180 ° around the axis of the container (1). According to an advantageous manufacturing method, the fluids

(9, 10) are permanently introduced. The external wall (3) has for this purpose one, or even two orifices (7) close to the neck (5), and provided with shutters.

In some cases, the user will find it preferable to periodically change the heat-conducting liquid (9), especially if it is water. One of the two orifices (7) makes it possible to extract and then introduce the water into the chamber (24) delimited by the double wall (2,3). The second identical orifice (7) allows the simultaneous evacuation of air. The openings (7) are closed after this operation.

However, the orifice (7) can be unique and allow the opposite and simultaneous movements of the water (9) and the air (10) if it is sufficiently dimensioned for this purpose.

In the third embodiment shown schematically in Figures 3a and 3b, the outer wall

(3) has two orifices (7,8) which are close to the neck

(5) and which are fitted with shutters. A membrane (12) is placed between the part of the internal wall (2) constituting the bottom (22), and the bottom part (23) of the external wall (3) opposite.

One of the orifices, for example the orifice (7), makes it possible to introduce into the internal chamber (24) of the double wall

(2,3), located above the membrane (12), a thermally conductive fluid (9). The second orifice (8) allows the evacuation of air. The openings (7,8) are closed after this operation.

The part (13) of the chamber (24) between the membrane (12) and the outer bottom (23) of the container (1) facing the membrane (12) remains filled with air. As was seen previously with respect to the first two embodiments of the invention, the volume of the part

(13) of the chamber (24) originally filled with air is greater than 50% of the total volume of the chamber (24) and therefore greater than the volume of the part of said chamber situated above the membrane (12).

The double wall (2,3) filled in this way has, for the most part, a high thermal conductivity which promotes thermal transfers between the enclosure (4) and the environment. The drink can therefore be easily reheated, cooled or kept at the appropriate temperature, ie the ideal temperature for consumption.

At all times, the membrane (12) is broken, as shown in Figure 3b, and the thermally conductive fluid

(9) flows by gravity into the space (13) located in below, while the air (10) replaces it in the part of the double wall (2, 3) located to the right of the enclosure (4).

Under these conditions, the heat exchanges between the drink and the outside are limited, and said drink therefore retains its optimum temperature.

Advantageously, these containers, of the "mineral water bottle", "soda bottle", "beer can" types, or

"gourd", are made of plastic or aluminum, or any other material compatible with the product to be thermally insulated.

As examples of products which may be contained in a container in accordance with the invention, it is possible to cite, without this list being exhaustive:

- water, mineral or not, carbonated or not, milk and other liquid or solid foods based on milk, drinks based on tea, coffee or chocolate, soups and soups, sodas, juices fruit, beer, a soft drink of the lemonade or cooler type, wine, an alcohol of the vodka type in the case of food products, - blood in the case of a non-food liquid,

- organs, for transplantation.

It goes without saying that the invention is not limited to the single embodiment above, given by way of example; on the contrary, it embraces all possible variants of embodiments. Thus, the air volume / water volume ratio defined in the chamber (24) could be for example between 51/49 and 80/20, a small ratio, fairly close to 1, which can however be ideally sought to avoid that the container (1) has too high a height caused by the presence of the space (11) (Figures la and lb) or by that of the part (13) (Figures 3a and 3b).

Claims

1) Self-insulating container (1), preferably of the "bottle", "gourd", "can" or similar type, intended to directly receive a product, preferably a food product such as a drink, introduced or extracted, way of an opening

(5) closed by a plug (6), in an enclosure (4) delimited by an internal wall (2), said container further comprising an external wall (3) which, with the internal wall, delimits a chamber (24) closed, the major part of said internal wall (2) having a first state of high thermal conductivity and a second state of low thermal conductivity, said container being characterized in that it comprises transformation means, which are intrinsic to it, and mechanical control means (R, 12) for passing from said first state to said second state, in that, in the first state, the chamber (24) delimited by the double wall (2,3) comprises a thermally conductive liquid (9) filling at least the part of said chamber which is situated in line with the enclosure (4) and in that, in the second state, the chamber (24) delimited by the double wall (2,3) comprises a thermally insulating gas (10) filling at least the par tie of said room which is located to the right of the enclosure (4).

2) Self-insulating container (1) according to claim 1, characterized in that the thermally conductive liquid (9) and the thermally insulating gas (10) present in the double wall (2, 3) are respectively water and air.

3) Self-insulating container (1) according to any one of claims 1 and 2, characterized in that the chamber

(24) delimited by the double wall (2,3): a) contains a first fluid (9) of high thermal conductivity and a second fluid (10) of low thermal conductivity, said first and second fluids (9,10) being of different densities and immiscible with each other, b) has an asymmetry (11) such that, in a first position of the container (1) corresponding to the first state, most of the internal wall (2) is wetted by the first fluid (9) and, in a second position of the container corresponding to the second state, most of said internal wall (2) is wetted by the second fluid (10).

4) container (1) with self-thermal insulation according to claim 3, characterized in that the asymmetry results from a space (11), between the part (23) of the external wall (3) constituting the bottom of said container (1) and the part (22) of the internal wall (2) facing this bottom, the volume of said space (11) being greater than 50% of the total volume of the chamber (24) delimited by the double wall (2, 3).

5) Container (1) with thermal self-insulation according to claim 4, characterized in that: a) the first fluid (9) is a liquid with high thermal conductivity, preferably water, and the second fluid (10) is a gas of low thermal conductivity, preferably air, b) the first position of the container corresponding to its first state is a first vertical position, the opening (5) or neck being directed downwards, and the second position of the container corresponding to its second state is a second vertical position in which the opening (5) or neck is turned upwards.

6) container (1) with self-thermal insulation according to claim 3, characterized in that the asymmetry results from a thickness (11) of the chamber (24) delimited by the double wall (2,3) which is greater at a part of the inner wall (2) constituting a side of the container (1) than it is at the part of the inner wall (2) diametrically opposite. 7) container (1) with thermal self-insulation according to claim 6, characterized in that: a) the first fluid (9) is a liquid with high thermal conductivity, preferably water, and the second fluid (10) is a gas of low thermal conductivity, preferably air, b) the first position of the container corresponding to its first state is a first horizontal position in which the part of the chamber (24) delimited by the double wall (2,3 ) with the greatest thickness

(11) is located above the container (1), and the second position of the container corresponding to its second state is a second horizontal position in which the part of the chamber (24) delimited by the double wall (2,3) having the greatest thickness (11) is located below said container (1).

8) Self-insulating container (1) according to any one of claims 1 and 2, characterized in that the mechanical transformation and control means comprise a frangible membrane (12) placed between the part of the external wall (3 ) constituting the bottom (23) of said container (1) and the part (22) of the internal wall (2) facing this bottom, and intended to release by gravity the thermally conductive liquid (9) above jacent, as well as a thermally insulating gas (10), preferably air, filling the space (13) between said membrane

(12) and the part of the external wall (3) constituting the bottom (23) of the container (1).

9) Self-insulating container (1) according to claim 8, characterized in that the mechanical control means comprise means for breaking, preferably by impact or pressure, the membrane (12).

10) Self-insulating container (1) according to any one of claims 1 to 9, characterized in that the double wall (2,3) is made of plastic or aluminum or any other material compatible with the product to be thermally insulated. Self-insulating container (1) according to any one of Claims 1 to 10, characterized in that the first and second fluids (9,10) are introduced permanently into the chamber (24) delimited by the double wall (2 , 3) at the time of manufacture of said container.