The invention relates to a vacuum storage box and to a vacuum storage system comprising such box.
In the food-processing field, vacuum technology is increasingly being used for storing organic materials, in particular food. This vacuum technology prevents the oxidation of organic materials by reducing the amount of oxygen in contact thereof. Compared to other sterilization methods, in particular heat sterilization, the vacuum method best preserves the organoleptic properties and vitamins of food.
For organic materials which are sensitive to temperature variations, storage boxes, in addition to being under vacuum, have to be placed in specific enclosures, either cold or hot as appropriate, in order to preserve the organic materials contained in such containers. The preservation of organic materials thus requires maintaining, accordingly, either a cold chain or a hot chain, which is restrictive.
It is known from WO-2018 189 351-A1 how to use a box with a container and a lid, the container comprising a tube, formed in the walls of the container, which allows vacuum to be created inside the container when the container is placed on a base comprising a vacuum pump. The tube is connected to a system of ducts and valves built-in into the lid, which, overall, provides satisfaction. WO-2018 189 351-A1 is however silent about food preservation when a particular temperature, either cold or hot, is required.
DE-296 17 720-U1 describes, e.g. an insulating box with a double-wall forming a vacuum cavity, for keeping food warm. DE-296 17 720-U1 does not discuss food preservation.
The invention more particularly addresses a way to remedy such problems, by proposing a vacuum storage box which is less sensitive to temperature variations.
For this purpose, the present invention relates to a vacuum storage box, comprising a container and a lid for closing the container. The container comprises a body with an inner wall and an outer wall, the inner wall delimiting an inner volume of the container, wherein the inner volume is open upwards when the container is placed on a horizontal surface. The inner and outer walls are connected to each other at an edge and define therebetween a first cavity, the edge having a closed contour. The lid comprises a body with a boundary having a closed contour and intended to press tightly against the edge of the container when the lid is assembled with the container in a closed configuration of the box. According to the invention, the first cavity leads to the outer environment through at least one opening, each opening comprising a first non-return valve, which lets the gas flow from the first cavity to the outside and prevents the gas from flowing from the outside towards the first cavity, while the first cavity leads to the inner volume through at least one passage.
According to the invention, the container is thermally insulating when the vacuum is created inside the first cavity. In this way, heat exchange is limited between the food housed inside the inner volume of the container and the outer environment, which increases the shelf life for food sensitive to temperature. When food is refrigerated, the cold is maintained longer; in contrast, when hot food is put in the vacuum storage box, the food remains hot for several hours and can be eaten without the need to be heated up, e.g. using an oven.
According to advantageous but not mandatory aspects of the invention, such a vacuum storage box may include one or more of the following characteristics taken according to any technically permissible combination:
According to another aspect, the present invention relates to a system for storing under vacuum, a quantity of organic material, in particular a food, comprising a box as described above and a base for receiving the box. The base comprises a vacuum pump connected to a duct, the duct being intended to be connected to the opening of the container when the box is received by the base.
Advantageously, the base comprises a pattern in relief for centering the duct of the base with respect to one of the openings of the container of the box.
The invention will be better understood and other advantages thereof will appear more clearly in the light of the following description, of five embodiments for a vacuum box and a vacuum system according to the principle thereof, given only as an example and making reference to the enclosed drawings, wherein:
A vacuum system 2 is shown in
The food 42 is not part of the invention but contributes to illustrate the principle thereof. In the example shown, the food 42 comprises both a solid and a liquid portion.
In
The base 20 comprises a centering pattern in relief 24, which is provided on the upper surface 22 and which mates with a matching pattern in relief 63 of the container 60, in order to provide a correct positioning of the container 60 with respect to base 20 when a bottom 65 of the container 60 is placed on the upper surface 22 of the base 20.
In the example shown, the centering pattern in relief 24 is provided and protrudes from the surface 22 and has a truncated cone shape centered on an axis A24, which is vertical here, while the matching pattern in relief 63 of the container 60 is arranged as a recess on the bottom 65 of that container.
The base 20 further comprises a pump 26 and a duct 28.
The duct 28 consists of a first end 282, which is connected to the pump 26, and a second end 284, opposite the first end, which leads to the upper surface 22. It is understood that the pump 26 is configured for aspirating a quantity of air through the duct 28 and to discharge said quantity of air toward the outside environment.
In the example shown, the duct 28 leads from the surface 22 to the center of the pattern in relief 24, i.e. the second end 284 is aligned with the axis A24.
The container 60 comprises a body 62 with an inner wall 64 and an outer wall 66. The inner 64 and outer 66 walls are connected to each other at an edge 68, which has a closed contour. In the example, the container 60 has an overall revolution form about an axis A60 which is merged with the axis A24 when the container 60 is placed on the base 20, with the edge 68 having a truncated cone shape centered on the axis A60 and flared upwards. The axis A60 is thus vertical when the bottom 65 of the box 60 is placed on a horizontal surface.
In the example, the bottom 65 is part of the outer wall 66, which further comprises a peripheral wall 67.
The inner wall 64 comprises a bottom 642 and a side wall 644, which delimit an inner volume V64 of the container 60, while the inner wall 64 and the outer wall 66 define therebetween, a first cavity V66, which is closed, i.e. isolated from the outside by the walls 64 and 66 and by the edge 68.
In the configuration shown in
The first cavity V66 leads to the outer environment through an opening 70 equipped with a non-return valve 72, as shown schematically on a larger scale in
The non-return valve 72 has a built-in plugging component 722, which has here the shape of a ball and which is loaded by an elastic component 724, shown here as a spring. The non-return valve 72 of each opening 70 allows the gas to flow from the cavity V66 toward the outside and prevents the gas from flowing from the outside toward the cavity V66. The second end 284 of the duct 28 is equipped with a nipple—which is not shown—which fluidically connects the duct 28 with the opening 70.
The cavity V66 leads to the inner volume V64 through a passage 74. In the example shown, the passage 74 is provided through the edge 68 near a junction corner 682 between the edge 68 and the inner wall 64. Thus, the air is not prevented from flowing through the passage 74 when the lid 80 is fitted onto the container 60 in a closed configuration of the box 40, as shown in
Advantageously, a flap 76 is provided in the passage 74 which leads directly to the inner volume V64. The valve 76 allows the gas to flow from the inner volume V64 toward the cavity V66 but is configured so as to prevent the organic materials 42 contained in the container 60 from penetrating into the cavity V66. More particularly, when the organic materials 42 comprise a liquid portion, the valve 76 prevents the liquid from flowing from the inner volume V64 toward the cavity V66.
Optionally, the valve 76 is also the “non-return” type, with a similar structure to the valve 72. A non-return type valve 76 is shown schematically and on a larger scale in
Other types of valves 76 are also conceivable.
The container 60 has a maximum level graduation 78, which is shown as a dotted-dashed line in
In the example shown, a distance d78 between the bottom 642 of the inner wall 64 and the graduation 78, measured parallel to the axis A60, is equal to 75% of a height h64 between the bottom 642 of the inner wall 64 and the junction corner 682 of the edge 68 with the inner wall 64. The value of the ratio d78/h64 can vary between 0.5 and 0.95, depending on the height of the container 60.
Each passage 74 is located, at height, between the graduation 78 and the lid 80 assembled with the container 60 in the closed configuration of the box 40, so as to prevent the liquid to flow from the inner volume V64 toward the first cavity V66.
The lid 80 comprises a body 82 with a boundary 84. The boundary 84 has a closed contour. The lid 80 is configured for pressing tight against the edge 68 of the container 60. In this example, the boundary 84 has a truncated cone shape, with an angle at the vertex which is the identical to the angle of the edge 68. Thus, in the closed configuration of the box shown in
Advantageously, a sealing component 86 is fitted therebetween the boundary 84 of the lid 80 and the edge 68 of the container 60. The sealing component 86 is housed here inside a groove 840 provided in the boundary 84 of the lid 80. In a variant, the sealing component 86 can be housed on the edge 68 of the container 60, in particular in a groove in the edge 68.
The sealing component 86 is advantageously removable, so as to facilitate the cleaning of the lid 80 and of the sealing component 86, and to make it possible to replace the sealing component 86 when same is damaged.
The sealing compound 86 is here an O-ring with a rectangular section, with two opposite sides 862 arranged parallel to the boundary 84 of the lid 80, and two other opposite sides 864 arranged orthogonal to the boundary 84.
A width L86 of the sealing compound 86 is defined as a distance between the two opposite sides 864, measured parallel to the boundary 84. Similarly, a thickness E86 of the sealing component 86 is defined as a distance between the two opposite sides 864 of the sealing component 86 measured orthogonal to the boundary 84 of the lid 80.
Since the box 40 is intended for the preservation under vacuum of organic materials such as food, the sealing compound 86 is preferentially made of a material suitable for contact with food and resistant to the flowing of gases. Thus, the sealing component 86 is preferentially made of silicone, preferentially manufactured by pressure molding, so as to reduce the porosity of the material. When the vacuum is created in the inner volume V64, the sealing component 86 is compressed between the boundary 84 and the edge 68, since gas infiltrations tend to occur through the sealing component 86 in the direction of the width, i.e. between the opposite sides 864 separated by the width L86. In order to make gas infiltrations through the sealing component 86 as small as possible, the sealing component 86 has the largest possible ratio L86/E86 between the width L86 thereof divided by the thickness E86 thereof. Thus, the ratio between the width L86 divided by the thickness E86 is greater than 5, preferentially greater than 8, preferentially greater than 12. For practical reasons when manufacturing the seal 86, the ratio L86/E86 is kept smaller than or equal to 50, preferentially to 25.
Advantageously, the lid 80 comprises an inner wall 88 and an outer wall 90, opposite the inner wall 88. In other words, the lid 80 has a double-skin. In the closed configuration of the box, the inner wall 88 faces the inner volume V64 of the container 60. The inner wall 88 and outer wall 90 are joined to each other by the boundary 84 and define therebetween a cavity V80. The cavity V80 is closed, and a partial vacuum is created inside the cavity V80 so that the lid 80 is thermally insulating.
Schematically, according to the kinetic theory of gases, the temperature of a gas and the thermal conductivity of a gas depend on the collisions between the molecules of said gas. When the pressure of the gas decreases and a partial vacuum is created, the probability of collision between the gas molecules decreases, and so does the thermal conductivity. More generally, when a partial vacuum is created in a closed volume, such as the cavity V80, said volume becomes thermally insulating. The partial vacuum in the cavity V80 is created at the factory when the lid 80 is manufactured, unlike the partial vacuum created by a user in the cavity V66 or in the inner volume V64, as explained herein.
The lid 80 further comprises a valve 92 which connects the outer environment to the inner volume V64 in the closed configuration of the box 40. The valve 92 is configured for being handled by a user at the opening of the box 40; from the outside of the closed box, so as to allow air to flow from the outside environment toward the inner volume V64 of the box 40 when the box 40 is in a closed configuration, i.e. so as to re-pressurize the inner volume V64. Without the intervention of a user, the valve 92 does not allow air to flow through.
The operation of the vacuum system 2 is further described.
First, a user places the container 60 on the upper surface 22 of the base 20, so that the pattern in relief 24 corresponds with a matching pattern in relief provided in the outer wall 66 of the container 60. The duct 28 of the base is thus aligned with the opening 70 of the container 60. In other words, the pattern in relief 24 is a centering pattern in relief of the duct 28 of the base with respect to one of the openings 70 of the container 60.
The user then places a quantity of organic matter 42 which they wish to preserve in the inner volume V64 of the container 60, taking care not to exceed the graduation 78, and then close the container 60 with the lid 80. Of course, the user can also fill the container 60 and assemble the lid 80 with the container 60 before installing the container 60 on the base 20. The vacuum system 2 is then in the configuration shown in
The user then actuates the pump 26 of the base 20, e.g. via of an on/off button which is not shown. Alternatively, the base 20 comprises a sensor 30 configured for detecting the presence of the container 60 on the base and/or automatically controls the start of the pump 26, as considered in WO-2018/189351-A1.
The pump 26 thus draws the gas contained in the cavity V66 via the duct 28 which is fluidically connected to the cavity, through the non-return valve 72 which allows free-flow in this direction. The gas contained within the inner volume V64 is sucked up into the cavity V66, via the passage 74 and through the non-return valve 76 which allows free-flow in this direction, due to the partial vacuum created inside the cavity. The air coming from the inner volume V64 is discharged outwards through the non-return valve 72, the duct 28, and the pump 26.
Thus, under the action of the pump 26, a partial vacuum is created both inside the cavity V66 and inside the inner volume V64. When the partial vacuum level reaches a suitable level which is chosen by the user or by a control device 32 of the system 2, the pump 26 stops and the user can remove the box 40 from the base 20. Due to the non-return valve 72, the outside air cannot flow from the outside toward the cavity V66. The partial vacuum is maintained in the cavity V66 and in the inner volume V64, and the partial vacuum inside the inner volume V64 holds the lid 80 in place over the container 60, by compressing the seal 86 which efficiently isolates the inner volume V64 from the outside environment.
Due to the partial vacuum in the cavity V66, the cavity V66 is thermally insulating, i.e. heat transfers between the inner volume V64 and the outside environment are reduced. Thus, when a quantity of organic matter initially refrigerated is placed in the box 40 and then put under vacuum, the organic matter is both preserved by the vacuum and maintained longer at low temperature due to the thermally insulating character of the container 60. The preservation of organic matter is thus extended.
In contrast, if an initially hot quantity of organic matter, e.g. a cooked dish which is still hot, is placed in the box 40, the placing under vacuum of the box 40 makes it possible to preserve the dish by reducing the oxidation due to oxygen from the air and to keep the dish warm for longer. It is thus possible to eat the dish hot several hours after the closure of the box 40, without having to reheat it, which is particularly convenient and saves energy.
The box 40 of the first embodiment is intended to be used for food packaging in a household or a professional kitchen. Same is intended to be handled by hand, on a counter, to be placed it in a refrigerator, freezer, dish warmer or oven, and the inner volume V64 thereof has a size between a few cubic centimeters and a few liters.
In the other embodiments shown in
A vacuum storage box 240, according to a second embodiment of the invention, is shown in
The container 260 has here a capacity of several tens or even several hundreds of liters or a few cubic meters, and is intended to receive liquid organic materials, e.g. oil, or solid organic materials, e.g. fruits. The container 260 is shown here on a pallet 261, configured for being moved by means of a handling tool, which is not shown, such as a pallet truck or a forklift. For this purpose, the pallet 261 comprises passages 261A for receiving handling forks, which are not shown. In this embodiment, the pallet 261 is not part of the invention, it is just used to specify the context thereof.
The container 260 has a substantially parallelepiped shape, symmetrical with respect to an axis of symmetry A260. The container 260 comprises a body 262 with an inner wall 264 and an outer wall 266. The inner wall delimits an inner volume V264 of the container 260, the inner volume V264 being open upwards when the container 260 and the pallet 261 are placed on a horizontal surface S. The inner 264 and outer 266 walls are connected to each other at an edge 268 and define therebetween a cavity V266, which is closed.
The lid of the box 240 comprises a body with a boundary which mates with the edge 268 so as to press tightly against the edge 268 of the container 260 when the lid is assembled with the container 260.
In a variant, the container 260 and the lid thereof together form a box in the shape of a barrel or cask with a circular section.
The cavity V266 leads to the outside environment through at least one opening 270. In
The opening or each opening 270 comprises a non-return valve 272, which allows gas to flow from cavity V266 outwards and prevents gas from flowing from the outside toward cavity V266.
The cavity V266 leads directly to the inner volume V264 through at least one passage 274, which is located here on edge 268, near the corner between the edge 268 and the inner wall 264. Each passage 274 leads to the inner volume V264 when the lid is assembled with the container 260 and is located between a graduation 278 of maximum level and the lid assembled with the container 260.
Advantageously, each passage 274 comprises a second valve 276, where each second valve is configured for preventing the flow of liquid from the inner volume V264 toward the first cavity V266, while allowing the gas to flow from the inner volume toward the first cavity.
More generally, it is understood that despite the difference in size and scale between the container 260 of the second embodiment and the container 60 of the first embodiment, the containers 60 and 260 work overall in the same way, i.e. each comprises a cavity V66 or V266 wherein it is possible to create a partial vacuum and which is connected by at least one passage 74 or 274 to the inner volume V64 or V264 of the box which can thus be depressurized with said cavity. Of course, the other elements of the vacuum system 2 are adapted accordingly, e.g. the sizing of the pump, the choice of the materials of the container 260 and of the associated lid. The container 260 and the associated lid e.g. are made of stainless steel, which is suitable for contact with food.
A vacuum storage box 340, according to a third embodiment the invention, is shown in
The box 340 has a similar shape and size to the box 40 of the first embodiment, with a container 60 and a lid 80 for closing the container 60.
One of the main differences between the box 340 of the third embodiment and the box 40 of the first embodiment is that, in the third embodiment, the cavity V66 defined between the inner 64 and outer 66 walls of the container 60 leads to the inner volume V64 through the lid 80, by a passage 74 provided through a top edge 68 of the container 60 which is fluidically connected to a duct 328 provided in the lid 80.
More specifically, the duct 328 comprises a first end 328A, which is positioned opposite to, and fluidically connected to the passage 74 of the container 60, and a second end 328B, opposite the first end 328A, which leads to the inner volume V64 through an orifice 96. When a sealing component, optional and similar to the sealing component 86 of the first embodiment, but not shown in
The lid 80 of the third embodiment comprises a valve 376, which is arranged in the vicinity of the second end 328B of the duct 328, here in the hole 96. In other words, the valve 376 is located, with respect to the passage 74, opposite the cavity V66. In the example in
When a vacuum pump, which is not shown, is fluidically connected to the opening 70 and aspirates a certain quantity of gas, a partial vacuum is created in the cavity V66 and, via the duct 328, in the inner volume V64, the valve 376 allows the gases to flow from the inner volume V64 toward the cavity V66 through the duct 328 and the passage 74. Thus, a partial vacuum is present both in the cavity V66, which is thermally insulating, and in the inner volume V64, which makes it possible to preserve the organic materials that are placed therein.
A vacuum storage box 440, according to a fourth embodiment of the invention, is shown in
The box 440 is similar in size to box 240 of the second embodiment, with a container 260 and a lid 280 for closing container 260. The lid 280 has here a double-skin and a structure similar to that of the lid 80 of the first embodiment, i.e. with an inner wall 88 and an outer wall 90 which delimit therebetween, a cavity V80, which is closed and wherein a partial vacuum is created, so that the lid 280 is thermally insulating.
Among the differences between the box 440 of the fourth embodiment and the previous embodiments, the box 440 comprises passages 461A for handling, similar to the passages 261A of the pallet 261, but which are provided directly in a bottom 265 of the container 260. Thus, the box 440 is in the form of a pallet. The box 440 can thus be moved by means of a handling tool (not shown), such as a trolley equipped with forks, and can be placed on a base provided for this purpose for an automatic fluidic connection of the opening 270 to an end piece of a duct connected to a vacuum pump of the base, the base not being shown.
The lid 280 here has a parallelepiped shape, the lid 280 pressing tight against the edge 268 at the boundary 284, which is here a peripheral portion of the inner wall 88.
In the fourth embodiment, the cavity V266, provided in-between the inner 264 and outer 266 walls of the container 260, leads to the outside environment through an opening 270, which is provided in the bottom 265 of the container 260. The opening 270 comprises a non-return valve (272), which allows gas to flow from the cavity V266 to the outside and prevents gas from flowing from the outside toward the cavity V266.
On the other hand, the cavity V266 leads directly into the inner volume V264 through a passage 274, which is provided here in the inner wall 264 and is located between a graduation 278 of maximum level and the lid 280 assembled with the container in the closed configuration of the box 440.
A vacuum storage box 540, according to a fifth embodiment of the invention, is shown in
The box 540 has a similar shape and size to those of the box 440 of the fourth embodiment, with a container 260 and a lid 280 wherein a cavity V80 is provided.
One of the main differences between the box 540 of the fifth embodiment and the box 440 of the fourth embodiment, is that in the fifth embodiment, the cavity V266 of the container 260 does not lead directly to the inner volume V264, but is fluidically connected to the cavity V80 of the lid, the cavity V80 leading to the inner volume through a main hole 96 provided in the inner wall 88 of the lid 280. Thus, in this embodiment, the cavity V80 of the lid 80 extends the cavity V66, in a similar way to the duct 328 of the third embodiment.
More precisely, two passages 274 are provided through the edge 268 which connects the inner 264 and outer 266 walls to each other.
In
The main hole 96 is provided here in the inner wall 88 in the middle of the two peripheral holes 94. Thus, by extension, the cavity V266 leads to the inner volume V264 through each passage 274 and through the peripheral holes 94, the cavity V80 and the main hole 96.
A valve 376 is housed in the main hole 96. The valve 376 is configured for preventing the liquid from flowing from the inner volume V264 toward the cavity V80 of the lid 280. Since the cavity V80 is fluidically connected to the cavity V266 of the container, the valve 376 also prevents the flow of liquid from the inner volume V264 toward the cavity V266 of container 260.
In other words, with respect to the passage 274, the valve 376 is located opposite the cavity V266 and prevents the flow of liquid from the inner volume V264 toward the cavity V266 while allowing the gas to flow from the inner volume V264 toward the cavity V266 of the container 260, through the main hole 96, the cavity V80, the peripheral holes 94, and the passages 274.
When a vacuum pump (not shown), is fluidically connected to the opening 270 and sucks up a certain quantity of gas, a partial vacuum is created in the cavity V66 and, via the passages 274 which are fluidically connected to the opposite peripheral holes 94, a partial vacuum is further created in the cavity V80 of the lid 280. Since the cavity V80 is further open through the main hole 96 towards the inner volume V264, a partial vacuum is created in the inner volume V264.
Thus, by means of only one vacuum pump, it is possible to create a partial vacuum both in the cavity V266 of the container 260 and in the cavity V80 of the lid 280, which are then thermally insulating, and at the same time in the inner volume V264, which helps to preserve the organic materials which are placed thereof.
According to a variant, not shown, of the first to the fourth embodiments of the invention, a plurality of passages of the type of the passage 74 or 274 may be provided for connecting the cavity V66 or V266 to the inner volume V64 or V264, each passage being equipped, if appropriate, with a non-return valve of the type of the valve 76 or 276. In this way, a pressure drop can be produced more quickly in the inner volume V64 or V264 from the pressure drop created in the cavity V66 or V266. Such different passages can be distributed over the edge 68 or 268, about the axis A60 or V260, or at the upper part of the inner wall 64 or 264. According to another variant, a plurality of holes of the type of the holes 96 can be provided in the third and the fifth embodiments.
In a variant, a valve blocking liquids and solids, but letting through gases in both directions, is mounted in each passage 74 or 274 or in the hole 96.
According to another variant, in particular if it is possible to guarantee that no product is in danger of falling on the passage(s) 74 or 274, said passage or passages are not equipped with a non-return valve.
According to another not shown variant of the invention, a plurality of openings of the type of the opening 70 or 270 can be provided for connecting the cavity V66 or V266 to the outside, each being equipped with a non-return valve of the type of the valve 72 or 272. In this way, a pressure drop can be more rapidly achieved in the cavity V66 or V266, in particular by using a plurality of pumps 26 and a plurality of ducts 28.
The opening(s) 70 or 270 and equivalent openings can be provided on the bottom 65 or on the peripheral wall 67 or 267 of the container 60 or 260.
In a variant, a seal of the type of the seal 86 in the first embodiment can be provided in each of the other embodiments. In such a case, the geometry thereof is suitable for not obstructing the flow of gas through the passage(s) 74 or 274.
In a variant, the lid 80 or 280 of the first and the fourth embodiments or the lid (not shown) of the second embodiment can have only one skin.
The embodiment and the variants mentioned above can be combined with each other so as to generate new embodiments of the invention. In particular, the lids of the boxes of the second to the fifth embodiments can each be equipped with a valve of the type of the valve 92 of the first embodiment, allowing the inner volume V64 and the cavity V66 to be re-pressurized when it is appropriate to open the box. In a variant, such valve can be mounted on the container 60 or an equivalent container, in particular on the outer wall 66 thereof instead of being mounted on the lid.
Number | Date | Country | Kind |
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FR2001708 | Feb 2020 | FR | national |
This application claims benefit under 35 USC § 371 of PCT Application No. PCT/EP2021/054107 entitled BOX FOR PRESERVATION UNDER VACUUM AND VACUUM-APPLICATION SYSTEM COMPRISING SUCH A BOX, filed on Feb. 19, 2021 by inventor Jean-Françis Bourrec. PCT Application No. PCT/EP2021/0554107 claims priority of French Patent Application No. 20 01708, filed on Feb. 20, 2020.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2021/054107 | 2/19/2021 | WO |