WO2001077594A1

WO2001077594A1 - Cooling device

Info

Publication number: WO2001077594A1
Application number: PCT/FR2001/001052
Authority: WO
Inventors: Vincent Letendart; Ali Nicolas Menault
Original assignee: Power-Flex S.A.R.L.
Priority date: 2000-04-07
Filing date: 2001-04-06
Publication date: 2001-10-18
Also published as: AU4848901A; FR2807503A1

Abstract

The invention concerns a device and a cooling method using elements capable of being preserved at room temperature without any particular time constraints, of being transported and used independently without requiring to be connected to any particular infrastructure, such as a power source. It is useful in particular for cooling a beverage. It consists in a cooling device operating by expansion of liquefied gas, characterised in that it comprises a non-sealed chamber (1), wherein the product to be cooled (B) is placed and wherein is input, through intake means (5) a pressurised coolant consisting in liquefied gas (6) part of which at least is expanded therein, said gas having physico-chemical properties so that at least part is preserved in liquid phase in the chamber (1) for a certain time, so as to cool the core product (B).

Description

Cooling device

The present invention relates to a cooling method using elements which can be kept at room temperature without any particular time constraints, and which can be transported and used independently without requiring connection to a particular infrastructure, such as an energy source.

The present invention also relates to a cooling device implementing this method which can be transported and used independently without requiring connection to a particular infrastructure, such as an energy source.

The method or the device according to the present invention can also be used by connection to an infrastructure and make it possible to obtain cooling by a material comprising few moving parts, of reliable operation and of reduced bulk.

In the food sector, for example, it is desirable to be able to cool foodstuffs before consumption, and in particular drinks, for example canned or bottled. It is however obvious that the invention can be used in all fields having the use of a compact and efficient cooling process while being autonomous or simply punctual.

Such applications are in particular envisaged in industrial or medical fields, for example for consumable products requiring cooling for their implementation, and tools and machines. Likewise, applications are envisaged in the field of conservation, medical or food, for initiating or regenerating cooling intended for the conservation of organs or living products or food products. In the current state of the art, in the food sector for example, when it is desired to cool a drink, it must be placed in a refrigerator, or in a receptacle containing ice cubes or pre-refrigerated elements.

On certain occasions it may be desirable to be able to do without such means, for example to be autonomous from any energy source, to avoid the congestion of a refrigerator, or to individualize the presentation of a product while including it the possibility of being eaten fresh.

Solutions to these needs are proposed for example in US patents 5,115,940, US 2,805,556 or FR 580,216 in the form of devices using a gas stored under pressure in a consumable cartridge which expands to cool the product. All of these solutions have the drawback of too brief and thermally ineffective contact between the refrigerant and the product to be cooled, because this refrigerant is in the gaseous state and quickly escapes from the device. These devices have moreover been used little or not in the fields of consumer products such as beverages.

The method according to the invention, which overcomes these drawbacks, consists inter alia of placing the product to be cooled in an unsealed enclosure in which the liquefied gas is initially triggered under pressure.

It is a cooling process using the expansion of a refrigerant, in the form of liquefied gas and stored under pressure and at room temperature, where the exhaust from the enclosure of the vaporized and expanded refrigerant is sufficiently slow to that the pressure in the enclosure containing the product increases as the gas is admitted. Due to this increase in pressure, provided that the refrigerant gas used is judiciously chosen as regards its physicochemical properties, it is possible to obtain a part of this refrigerant is in liquid form in the enclosure at the end of the intake phase. The liquid state of the refrigerant allows good heat exchange with the product, therefore good thermal efficiency, and prevents the refrigerant from escaping as quickly as if it were in gaseous form, which gives the product time to cool "to the core", that is to say throughout its thickness.

This object is achieved by a process of cooling by expansion of a liquefied gas according to claim 22.

The object of the present invention is also to propose a device which can be used to implement this method.

This object is achieved by a device for cooling by expansion of a liquefied gas according to claim 1.

Further developments of the invention are described in the dependent claims.

The invention, with its characteristics and advantages, will emerge more clearly on reading the description made with reference to the accompanying drawings in which: - Figure 1 shows a side sectional view of the device according to the invention in an applied embodiment a bottle, for example of Champagne, and using a valve type gas cartridge; 2 shows a side sectional view of the device according to the invention in another embodiment also applied to a bottle, for example of Champagne, and using a gas cartridge of the valve type; 3 shows a side sectional view of the device according to the invention in another embodiment applied to a drink in a metal can, and intended to use a external source (not shown) such as a pressurized tank or a valve type gas compressor.

In all of the descriptions presented here, it should be understood that the enclosure (1) designates the space, located inside the device, which rises in pressure when the refrigerant is admitted under pressure and then depressurizes slowly thereafter. .

In one embodiment of the device according to the invention, shown in FIG. 1, the bottle (B) is placed in an enclosure (1) in two parts comprising a body (2) and a cap (3). The enclosure is not waterproof and comprises, at its upper part, at least one vent (4) which makes it possible to control the expansion and in particular to keep the gas in liquid phase for a certain time. The body (2) and the cap (3) are assembled by closing means (not shown) and enclose the interior space of the enclosure (1). The vent (4) has a determined passage section, and may have means, of a known type, allowing the adjustment of this passage section.

The body (2) has in its lower part an intake duct (5), opening into the enclosure (1) and which can be put in communication with an arrival of liquefied gas coming from a source (S) under pressure. The passage section of the vent (4) is sufficiently small and the rest of the enclosure (1) is sufficiently leaktight so that, when one admits therein sufficiently quickly gas initially pressurized by the conduit of intake (5), the quantity of gas escaping from the enclosure through the vent is lower than the quantity admitted into the enclosure and therefore that the pressure in this same enclosure increases to a maximum value, corresponding to a situation of pressure balance between the source and the enclosure. From this point of equilibrium, the enclosure (1) undergoes slow depressurization, the duration of which is determined inter alia by the passage section of the vent (4).

The gas used is contained in a conventional cartridge (6), for example a cartridge where the outlet of the gas is controlled by a valve and where a pressure on the gas outlet nozzle is necessary to open said valve. The device according to the invention comprises means for holding the cartridge (6) in a position where it will be easy to transfer the liquid gas which it contains in the enclosure (1) via the conduit (5). . Means can be provided both on the cartridge and on the device for holding the cartridge in these guide means (7).

The body (2) of the device comprises a guide receptacle (7) making it possible to hold the cartridge (6) with its outlet nozzle (8) disposed downwards and applied against a usual diffuser (9), communicating with the conduit ( 5) which leads to the enclosure (1). By exerting pressure (F) on the bottom of the cartridge (6), the outlet nozzle (8) is displaced in the opposite direction and the admission of pressurized liquid refrigerant into the lower part of the enclosure (1).

In another embodiment (not shown), it is also possible to use a cartridge of the kind of those comprising a perforable cover. In this case, the diffuser (9) is provided with a perforating member.

In an embodiment shown in Figure 2, the enclosure (1) consists of a body (2) and a cap (3), assembled by closure means (14) as a screw fixing, these closing means comprising sealing means such as an O-ring (15). The body (2) and the cap (3) assembled enclose the enclosure (1) and have internal walls enclosing the bottle (B) to be cooled and delimiting around this same bottle a space (13) for circulation, tight towards the down, where the refrigerant can circulate.

On their face directed towards the bottle, these internal walls have so-called internal surfaces (21, 31) whose shapes are complementary to each other and to the external walls of the bottle, thus delimiting around this bottle a space (13) for circulation very low volume. So when pressure maintenance or slow depressurization of the enclosure (1), this small volume forces the liquid phase refrigerant to surround the bottle, and therefore to ensure liquid contact, over a large part of its height, even with a small amount of liquid. In the upper part of the circulation space (13) surrounding the bottle (B), the internal walls of the enclosure (1) comprise at least one opening (32) called an overflow leading the liquid refrigerant exceeding the volume space (13) for circulation in a space (33) called overflow which is also located inside the external walls (20,30) of the enclosure. In the lower part of the overflow space (33), the internal wall of the enclosure separating this same space (33) from the circulation space (13) surrounding the bottle has one or more return means ensuring the passage of heat, or passage of liquid, or both. These return means can be thermally conductive, for example by a thinning of the wall or the inclusion therein of a thermally conductive material. These return means can also consist of openings (34) either simply letting the liquid pass by gravity, or of a type allowing the passage of the liquid only slowly, or of a type allowing the passage of the liquid only from the space (33) of overflow towards the space (13) surrounding the bottle.

The return of the liquid refrigerant from the overflow space (33) to the space (13) surrounding the bottle allows this liquid to circulate, and thus ensures that most of this liquid is used for cooling. It also makes it possible to ensure the presence of liquid refrigerant in contact with the bottle as long as possible, even when a part of this refrigerant evaporates during its depressurization and its heating. The return openings (34) therefore allow the return in the space (13) surrounding the bottle of the liquid refrigerant part initially exceeding this same space (13), or the thermal use of this same share of liquid refrigerant, all avoiding as much as possible to allow the refrigerant initially entering the space (13) surrounding the bottle to leave this same space (13) before having filled it to its openings (32) of overflow.

In the upper part of the overflow space (33), the outer wall of the cap (3) carries an opening of a determined section called a vent (4), through which air and vapors escape refrigerant during depressurization. The passage section of this vent constitutes a determining parameter of the maximum pressure value reached in the enclosure during the admission of the liquid refrigerant under pressure, as well as the depressurization speed of the enclosure thereafter. In one embodiment, this passage section can be adjusted by any known adjustment means, for example a needle screw. This adjustment can be carried out continuously or discretely, between determined values or ranges of values, which can be provided for different cases of use of the device, and which can include a closed position. The enclosure may also include pressure limiting means

(not shown), for example in the form of a safety valve which can be located in the vent or in another part of the enclosure.

In one embodiment, the space (13) surrounding the product to be cooled comprises one or more elements made of a deformable or absorbent material or both. These elements can be attached to these walls or to the product during the process, for example in the form of an elastic band or a complete cover passed around the bottle before it is introduced into the enclosure.

These elements can also be fixed on the internal surfaces (21, 31) of the internal walls of the enclosure (1), for example in the form of a strip of foam or blocks of foam (35, FIG. 2) glued on the internal surface (31) of the cap and which will be slightly compressed by the bottle (B) when the cap (3) is closed. These blocks can then have gaps between them allowing the liquid coolant to pass during the filling of the space (13) surrounding the bottle, and have opposite one of the other forms (not shown) forcing the liquid to flow in contact with these foam blocks (35) when it descends by gravity. These absorbent elements allow the liquid refrigerant to remain longer in the upper part of the space (13) surrounding the bottle while slowing its descent, and will also retain all or part of this liquid refrigerant in contact with the bottle by absorption and capillarity. and allow it to cool the bottle in its upper parts even if the amount of liquid is insufficient in this space to fill it to the top.

When the device has one or more foam elements fixed on its internal walls (31), the return openings (34) may be located in locations on this wall where some of these blocks are glued (35), so as to reduce the passage of refrigerant to the overflow space (33) during filling, while allowing the return from this space (33) through the foam. In one embodiment, the conduit (5) for admitting pressurized liquid refrigerant comprises a non-return valve (50) preventing the enclosure (1) from being emptied by this conduit when the source is removed before the end. depressurization. When the source is a cartridge (6), this valve also makes it possible to prevent the pressure in the enclosure from lifting or ejecting this cartridge (6) out of its location in the guide means (7) which receive it. .

In one embodiment, the coolant inlet pipe (5) opens into the enclosure (1) in its lower part under the bottom (B0) of the bottle (B) to be cooled. This conduit then opens into one or more channels (51) formed in the upper surface (53) of the inner wall of the enclosure in a substantially planar part located under the bottom of the bottle. This upper surface (53) then carries an element called base (52), which remains attached to it in normal use. This base (52) has a shape complementary to that of the bottom (B0) of the bottle, and therefore occupies the volume located under this bottom (B0), thus reducing the amount of liquid refrigerant accumulated under this bottom (B0). This base (52) is interposed between the axis (d5) of the opening of the intake duct (5) and the outside of the enclosure when the latter is open in normal use. This normal use having to be understood as the use of the device in the implementation of the method according to the invention, apart from other operations such as cleaning or changing parts, the presence of this base (52) avoids the risk projection of liquid refrigerant outside the enclosure if the latter is open during the admission of pressurized refrigerant, the liquid then being injected in the direction of the axis (d51) of the channels, and coming to strike the inner wall (21) of the enclosure. This base (52) can be removable, among other things for cleaning or maintenance of the device, it is also possible to provide a choice of different models of bases (52) depending on the shape of the product to be cooled. This choice of base can also be coordinated with a choice of annular shims of different thicknesses (not shown) adjusting the height of the bottle in the enclosure.

In another embodiment represented in FIG. 3, the invention can be applied in particular to the cooling of a drink in a usual cylindrical can, of the type of that containing sodas or carbonated drinks or not, with a lid with a single opening and often made of steel or aluminum.

The box (B) of beverage to be cooled is enclosed in an enclosure (1) consisting of a body (2) comprising an inner wall (21) substantially cylindrical and an outer wall (20), and a cover (3) movable around an axis (36) integral with the body (2) and closed by closing means (14) consisting of a thread (not shown) or an elastic hook connected to the body (2) and is clipping onto this cover (3). This cover comprises sealing means (15) in the form of an annular seal applying to the external wall (20) of the body (2) of the device. The source (S) of pressurized liquid refrigerant can be a cartridge (6, FIG. 1) of the valve type which opens when its outlet tube (8, FIG. 1) is pressed into the diffuser (9), or well from any type of known source such as a pressure tank or a compressor provided with injection means (not shown) which will be applied to the diffuser (9).

The liquid refrigerant under pressure is admitted by bringing a source (S) against a diffuser (9), and is led through the non-return valve (50) included in the body of the diffuser (9) and by the conduit ( 5) up to the channels (51) formed in the lower surface of a base (52), this base being fixed on the internal face of the bottom of the internal wall (21) of the enclosure (1). The channels have a trapezoidal shape and are covered by a part of the base which is interposed between the axis (d5) of the inlet opening of the duct (5) and the outside of the enclosure when the latter is open in normal use. This base can also have a shape complementary to that of the bottom (B0) of the box (B), thereby reducing the volume available for the liquid phase refrigerant.

During the intake, the liquid part of the refrigerant crosses the channels (51) and fills the space (13) surrounding the box (B). If and when this space (13) is full, the excess liquid passes through one or more overflow openings (32) in an overflow space (23) located between the internal wall (21) and the external wall (20) of the body (2) of the enclosure. This excess liquid can return to the space (13) surrounding the box through return openings (24) formed in the internal wall (21) and leading to elements (25) of deformable and absorbent foam which cover a part of this internal wall (21).

During depressurization, the refrigerant vapors escape through a vent (4) formed in the external wall (20) of the body of the enclosure (1). In order to adjust the duration of depressurization or the maximum pressure value reached during intake, the passage section of the vent (4) can be adjusted by means of adjustment, for example by rotation of the body of the diffuser (9), this diffuser body comprising a window (91) in the form of a groove communicating with the enclosure and which will be brought opposite the opening of the vent (4) during this rotation.

In another embodiment (not shown), the device applied to the cooling of a beverage in a cylindrical can can have in its lid an opening possibly provided with sealing means, this opening leaving the upper part of the can beyond outside the enclosure. The box being held in the enclosure by holding means of a known type, it will be possible to open the cover and consume the drink, for example with a straw, without removing the box from the device.

In one embodiment, the device according to the invention comprises one or more locating means (not shown), for example visual or audible, indicating one or more adjustments of duration or quantity of admission corresponding to specific types of product to cool, or to specific situations of use, for example as a function of temperature and pressure conditions, or to a combination of these elements. These marks can be replaced or supplemented by mechanical stops allowing these settings to be easily observed.

In one embodiment, the device according to the invention comprises one or more means of information (not shown), for example visual or audio, informing the user discreetly or continuously about the time elapsed since the admission of the refrigerant in the enclosure, the residual pressure in the enclosure, or the temperature of at least one of the elements present in the enclosure, or on a combination of this information. Information on the temperature may for example be displayed using an indicator including a thermochromic compound. In one embodiment, the device according to the invention comprises one or more safety mechanisms (not shown) making it possible to avoid certain manipulations which could, for example, compromise the proper functioning of the process or involve a risk for the user. Such a safety mechanism can be provided to prevent the admission of pressurized liquid refrigerant when the enclosure is open or improperly closed.

Such a safety mechanism may be provided to prevent the admission of liquid refrigerant into the enclosure when the latter contains a container which is not closed, for example to avoid the risk of contamination of the contents of the container with refrigerant under liquid form.

Such a safety mechanism can be provided to prevent the opening of the enclosure when the pressure is greater than a determined value.

In one embodiment, certain characteristics of the method according to the invention are more particularly described below by way of illustration and to facilitate understanding.

Vaporization and expansion The admission of pressurized refrigerant can be done in one or more stages, depending on the applications and needs.

At the start of a refrigerant intake time, when the liquefied gas passes from the source of liquid refrigerant under pressure to the enclosure (1), it changes from a high pressure prevailing in the source to a lower pressure prevailing inside the enclosure.

Because the enclosure is initially at atmospheric pressure, this pressure difference is large enough during at least part of the intake stage so that at least part of the admitted refrigerant vaporizes and then continues to expand. It should be noted that the vaporization can be done in several different regions of the device, including included in a diffuser (9, Figure 1) located directly at the inlet of the intake duct (5), according to the geometry of the elements constituting it and according to the temperature and pressure conditions during the process of using the device . These vaporization and gas expansion transformations are endothermic and absorb heat from all of the bodies present in the enclosure, the temperature of which drops at the same time but not uniformly. Indeed, these endothermic transformations are specifically undergone by the part of the refrigerant which vaporizes then expands, it is therefore this part of the refrigerant which loses heat and therefore whose temperature initially decreases.

On contact and mixing with the gaseous refrigerant, the still liquid refrigerant will see its temperature drop, to a lesser extent because it must give up heat to the coolest part of the refrigerant. By contact with the gaseous refrigerant, the bottle will also decrease in temperature but to an even lesser extent, because the contact between a gas and a smooth solid does not have good thermal efficiency.

Return to liquid phase

During an admission time of the pressurized liquid refrigerant, due to the low leakage rate authorized by the vent (4), the pressure rises in the enclosure to a maximum value between the two values initial chamber and refrigerant source pressure (S). By choosing a refrigerant having physicochemical characteristics such that it is gaseous at pressure and ambient temperature and liquid under the conditions of temperature and pressure prevailing in the enclosure during the maximum pressure reached during an admission time, at least part of the previously vaporized and expanded refrigerant is returned to the liquid phase. In the case, for example, of a bottle of Champagne, a good result is obtained with tetrafluoro ethane.

This part of the refrigerant was successively vaporized, expanded, and then liquefied. Because the liquefaction transformation has exactly the opposite effect from the thermal point of view (at identical mass) of the vaporization transformation, the balance of vaporization and liquefaction remains endothermic, since only part of the vaporized refrigerant has been re-liquefied .

The expansion transformation is also endothermic, the balance of all these transformations is endothermic, that is to say in the direction of heat absorption.

The part of vaporized refrigerant being that which caused the temperature drop, it is it which presents the lowest temperature in the enclosure. For example, the temperature of the vaporized refrigerant can then drop to around -40 ° C, for a cartridge at around 6 bars and an ambient temperature of around (20) ° C.

The liquefaction of part of this vaporized refrigerant will directly establish an excellent thermal contact between the coldest body and the bottle, as well as with the rest of the refrigerant which would not have been vaporized at the end of admission time.

Slow depressurization

Once the pressure balance between the source and the enclosure has been reached, or when the admission of pressurized liquid refrigerant is interrupted, the enclosure slowly depressurizes, at a speed depending on the passage cross section of the vent, as well as among other conditions of temperature and pressure outside the enclosure and possible pressure leaks or heat losses with the outside. Depending on the values of these parameters, the depressurization obtained in an implementation applied to a bottle of Champagne can be of the order of several minutes, for example at least 2 minutes. During this depressurization, the refrigerant in gaseous form will gradually escape through the vent while the refrigerant in liquid form will gradually vaporize, in whole or in part, still absorbing heat from the bodies present in the 'pregnant. For example, after a depressurization of approximately 4 minutes, the enclosure may still contain a portion of refrigerant in the liquid phase having a temperature below 0 ° C.

In addition, the liquid form of the refrigerant allowing a much better heat exchange with the bottle, the cooling of the bottle may be satisfactory at the end of this depressurization. As a comparative example, a bottle of Champagne should be left for around 30 minutes in the atmosphere of a freezer at -18 ° C to obtain a satisfactory result.

In one embodiment, the device according to the invention is characterized in that it comprises a non-sealed enclosure (1), in which the product to be cooled is placed and in which is admitted, by means of admission, a pressurized refrigerant consisting of a liquefied gas at least part of which relaxes therein, this gas having physicochemical properties so that at least part of it remains in the liquid phase in the enclosure for a certain time, so as to be able to cool the product to the core.

According to one feature, the device according to the invention comprises means which sufficiently limit the possible leakage rate outside the enclosure so that the rapid admission of the pressurized refrigerant causes the pressure in the enclosure to rise to conditions causing liquefaction or maintenance in the liquid phase of at least part of the refrigerant present in the enclosure.

According to one feature, the enclosure (1) is close enough to the seal and the operating characteristics of the leakage limitation means, called vent (4) are sufficiently limiting for this enclosure does not return to ambient pressure until after at least 30 seconds.

According to one feature, the refrigerant used is based on tetrafluoroethane. According to one feature, the enclosure has an internal wall, the internal surface (21, 31) of which complements the external shapes of a specific type of product to be cooled, leaving a space (13) between this internal surface and the product. low volume which, inter alia under the effect of pressure, forces the refrigerant in liquid phase in the enclosure (1) to rise above a determined height along the external walls of the product and therefore to ensure a large contact surface with this product.

According to one feature, the liquefied gas inlet is located at the bottom of the enclosure (1). According to one feature, the inner bottom wall of the enclosure supports on its upper surface (53), fixedly in normal use, an element called base (52) which is interposed between the axis (d5) of the opening refrigerant inlet and the outside of the enclosure once it is open in normal use, this base having a shape complementary to the concave shape of the external lower surface (B0) of a determined type of product to be cooled (B), like a bottle.

According to one feature, the enclosure is quasi-isothermal and made of a material which is not very heat conductive or comprises at least two walls separating the product from the outside, or both. According to one feature, the enclosure (1) is composed of a body (2) comprising intake means (5) and of a cap (3) which can be fixed to the body by means of closure (14) and possibly sealing means (15), the whole of this body and of this cap enclosing the space capable of receiving the product (B) to be cooled. According to one feature, the surface (21, 31) of an internal wall of the enclosure (1) limiting the space (13) surrounding the product present in an upper part of the enclosure at least one opening (32) called overflow, allowing the liquid phase refrigerant (Rie) exceeding the volume of this same space (13) to flow outside this internal wall into an overflow space (23, 33) located at inside the external walls (20, 30) of the enclosure.

According to one feature, at least one vent (4) communicates the outside air with the inside of the enclosure (1) at a location on the external walls (20, 30) of the enclosure receiving the vapors which come from the space (23, 33) of overflow receiving the liquid phase refrigerant (Rie) which exceeds the volume of the space (13) surrounding the product.

According to a particular feature, the overflow space (23, 33) communicates with the space (13) surrounding the product,

- Either thermally by conduction due to the material, the thickness or the structure composing a part of the wall (21, 31) separating them;

- Or by at least one opening comprising means allowing the circulation of the refrigerant in liquid phase from the space (23, 33) of overflow towards the space (13) surrounding the product;

- Either by at least one opening (24, 34) large enough to allow liquids to pass from one space to another slowly but not large enough for the liquid phase refrigerant to use this opening instead of mounting the along the product during an intake phase of said refrigerant;

- or by a combination of several of these means. According to one feature, the device according to the invention comprises one or more safety mechanisms preventing one or more of the situations from being caused

- or the refrigerant intake into the enclosure (1) when the latter is open or not closed properly;

- or the refrigerant inlet into the enclosure (1) when the latter contains a container which is not closed;

- Either opening the enclosure (1) when the pressure inside it is greater than a determined value. According to one particular feature, at least one vent (4) has an adjustable section opening between several determined values, possibly including complete closure, or within at least one range of such values, and thus determining the duration of the depressurization of the enclosure (1). According to a particular feature, the intake means (5) between the source (S) of pressurized liquefied refrigerant and the enclosure (1) comprise a closing means of the non-return valve type (50), allowing the entry of refrigerant in the enclosure but not the outlet.

According to a particular feature, one or more elements of the device include indications or stop mechanisms, or both, making it possible to adjust either the quantity of refrigerant admitted into the enclosure (1) during one or more intake operations, either the cooling time, or both.

According to one feature, at least part of the space (13) surrounding the product (B) contains a deformable absorbent material and capable of retaining the refrigerant in liquid phase by capillary action, the position and the shape of this absorbent material being determined by so that it is in contact with the product and possibly compressed by it for at least part of the duration of use of the device, and thus maintains a certain amount refrigerant in liquid phase in contact with it even occurs regardless of the position and the amount of remaining refrigerant in ^the chamber, or by retention of the refrigerant within the absorbent material, or by creating an obstacle to the dropout refrigerant in liquid phase along the walls of the product, ie both.

According to one feature, the absorbent material consists of a foam (35) adhering to at least part of the interior surfaces of the internal wall of the enclosure, or of a strip or cover surrounding the product, or of many of these. According to one feature, the liquefied gas is contained in a cartridge

(6) common of the kind of which the gas outlet is caused by ^the depression of its outlet nozzle which is connected by a conduit (5) to the enclosure (1).

According to one feature, the liquefied gas is contained in a usual cartridge of the kind of those whose outlet orifice is closed by a perforable, tear-off, or single-opening seal.

According to one feature, the device according to the invention comprises means (7) for holding the cartridge (6) in a position favoring the control of the opening of its valve. In one embodiment, the method according to the invention comprises steps of

- introduction of the product into a closed enclosure having a vent with a small passage section, which can be adjustable;

- admission in one or more stages of a pressurized refrigerant consisting of liquefied gas, causing a rise in pressure of the enclosure due to the low leakage rate authorized by the vent;

- at the start of a pressure refrigerant intake time, vaporization and expansion of at least part of this refrigerant, absorbing heat from the bodies present in the enclosure and lowering its temperature;

- At the end of an admission time, return to the liquid phase of at least part of the vaporized refrigerant, under the effect of the pressure rise in the enclosure;

pressure maintenance or slow depressurization of the enclosure, depending on the vent passage section, during which the liquid phase refrigerant is partly in contact with the product to be cooled, absorbing heat on its part and lowering temperature.

It should be obvious to those skilled in the art that the present invention allows embodiments in many other specific forms without departing from the scope of the invention as claimed. Therefore, the present embodiments should be considered by way of illustration, but may be modified in the field defined by the scope of the appended claims, and the invention should not be limited to the details given above.

Claims

1. A device for cooling by expansion of a liquefied gas, characterized in that it comprises an enclosure (1) which is not leaktight, in which the product to be cooled is placed and in which is admitted, by means of admission, a pressurized refrigerant consisting of a liquefied gas at least part of which relaxes therein, this gas having physicochemical properties so that at least part of it remains in the liquid phase in the enclosure for a certain time, so as to be able to cool the product at heart.

2. Device according to claim 1, characterized in that it comprises means sufficiently limiting the possible leakage rate outside the enclosure so that the rapid admission of the refrigerant under pressure causes the pressure in the enclosure to rise to conditions causing the liquefaction or maintenance in the liquid phase of at least part of the refrigerant present in the enclosure.

3. Device according to one of claims 1 to 2, characterized in that the enclosure (1) is sufficiently close to the seal and the operating characteristics of the leakage limiting means, called a vent (4) are sufficiently limiting so that this enclosure does not return to ambient pressure until after a period of at least thirty seconds.

4. Device according to one of claims 1 to 3, characterized in that the refrigerant used is based on tetrafluoroethane.

5. Device according to one of claims 1 to 4, characterized in that the enclosure has an internal wall, the internal surface (21, 31) of which complements the external forms of a specific type of product to be cooled, leaving between this interior surface and the product a space (13) of small volume which, inter alia under the effect of the pressure, obliges the refrigerant in liquid phase in the enclosure (1) to rise above a height determined along the external walls of the product and therefore to ensure a large contact surface with this product.

6. Device according to one of claims 1 to 5, characterized in that the intake of liquefied gas is located at the bottom of the enclosure (1).

7. Device according to one of claims 1 to 6, characterized in that the inner bottom wall of the enclosure supports on its upper surface (53), fixedly in normal use, an element called base (52) which s 'between the axis (d5) of the refrigerant inlet opening and the outside of the enclosure once it has been opened in normal use, this base having a shape complementary to the concave shape of the lower surface external (BO) of a specific type of product to be cooled (B), such as a bottle.

8. Device according to one of claims 1 to 7, characterized in that the enclosure is quasi-isothermal and made of a material which is not very conductive of heat or comprises at least two walls separating the product from the outside, or the of them.

9. Device according to one of claims 1 to 8, characterized in that the enclosure (1) is composed of a body (2) comprising intake means (5) and a cap (3) which can be fixed to the body by closing means (14) and possibly sealing means (15), the whole of this body and of this cap enclosing the space capable of receiving the product (B) to be cooled.

10. Device according to one of claims 1 to 9, characterized in that the surface (21, 31) of an internal wall of the enclosure (1) limiting the space (13) surrounding the product present in a part high of the enclosure at least one opening (32) called overflow, allowing the liquid phase refrigerant (Rie) exceeding the volume of this same space (13) to flow outside this internal wall in an overflow space (23, 33) located inside the external walls (20, 30) of the enclosure.

11. Device according to one of claims 1 to 10, characterized in that at least one vent (4) communicates the outside air with the interior of the enclosure (1) at a location on the external walls (20 , 30) of the enclosure receiving the vapors which come from the overflow space (23, 33) receiving the liquid phase refrigerant (Rie) which exceeds the volume of the space (13) surrounding the product.

12. Device according to one of claims 1 to 11, characterized in that the overflow space (23, 33) communicates with the space (13) surrounding the product,

- or by a combination of several of these means.

1 3. Device according to one of claims 1 to 12, characterized in that it comprises one or more safety mechanism preventing causing one or more of the situations

- or the refrigerant intake into the enclosure (1) when the latter is open or not closed properly; - or the refrigerant inlet into the enclosure (1) when the latter contains a container which is not closed;

- Either opening the enclosure (1) when the pressure inside it is greater than a determined value.

14. Device according to one of claims 1 to 13, characterized in that at least one vent (4) has an opening of adjustable section between several determined values, possibly including a complete closure, or inside at least minus a range of such values, and thus determining the duration of the depressurization of the enclosure (1).

15. Device according to one of claims 1 to 14, characterized in that the intake means (5) between the source (S) of pressurized liquefied refrigerant and the enclosure comprise a closing means of the non-return valve type ( 50), authorizing the entry of refrigerant into the enclosure (1) but not the outlet.

16. Device according to one of claims 1 to 15, characterized in that one or more elements of the device comprise indications or stop mechanisms, or both, making it possible to adjust either the quantity of refrigerant admitted into the enclosure (1) during one or more admission operations, either the cooling time or both.

17. Device according to one of claims 1 to 16, characterized in that at least part of the space (13) surrounding the product (B) contains a deformable absorbent material and capable of retaining the refrigerant in capillary phase liquid, the position and the shape of this absorbent material being determined so that it is in contact with the product and possibly compressed by it during at least part of the duration of use of the device, and thus maintains a certain quantity of refrigerant in liquid phase in contact with the same product regardless of the position and the quantity of refrigerant remaining in the enclosure, either by retention of the refrigerant within this absorbent material, either by constituting an obstacle to the fallout of refrigerant in liquid phase along the walls of the product, or both.

18. Device according to one of claims 1 to 17, characterized in that the absorbent material consists of a foam (35) adhering to at least a portion of the interior surfaces of the inner wall of the enclosure, or a band or cover surrounding the product, or of several of these elements.

19. Device according to one of claims 1 to 18, characterized in that the liquefied gas is contained in a cartridge (6) usual of the kind of those whose output of the gas is caused by the depression of its outlet nozzle which is connected by a conduit (5) to the enclosure (1).

20. Device according to one of claims 1 to 19, characterized in that the liquefied gas is contained in a usual cartridge of the kind of those whose outlet orifice is closed by a perforable, tear-off, or single-opening seal.

21. Device according to one of claims 6 to 20, characterized in that it comprises means (7) for holding the cartridge (6) in a position favoring the control of the opening of its valve.

22. Method for cooling a product, characterized in that it comprises stages of

- admission in one or more stages of a pressurized refrigerant consisting of liquefied gas, causing a rise in enclosure pressure due to the low leakage rate authorized by the vent;

- At the start of a pressure coolant admission time, vaporization and expansion of at least part of this coolant, absorbing heat from the bodies present in the enclosure and lowering its temperature;

- pressure maintenance or slow depressurization of the enclosure, depending on the vent passage section, during which the liquid phase refrigerant is partly in contact with the product to be cooled, absorbing heat on its part and lowering the temperature.