CARRYING DEVICE FOR TEMPERING OR HEATING FOOD

Description

[0001] The invention relates to a carrying device for food.

[0002] The amount of food prepared and pre-portioned for delivery to facilities such as hospitals, schools, daycare centers, canteens, etc., is constantly increasing. These pre-prepared meals make it possible to avoid the complex and costly setup of kitchens within these facilities.

[0003] To transport prepared food to the facilities, trolleys are known that are designed for transporting trays containing the food. Usually, hot and cold dishes, such as a roast and a salad, are transported together on one tray. For this purpose, the trolleys have two compartments designed for different temperatures. One compartment holds the trays with the cold dishes, and the other compartment holds the trays with the hot dishes. To prevent the food from exchanging temperatures, a partition is provided between the compartments.

[0004] FR 2 684 281 A1 describes such a transport trolley for storing and distributing food. The trolley is equipped with an insulated vertical partition featuring slots for two-zone food trays. One zone of the tray is for hot food, and the other for cold food. The trolley can be connected to a unit equipped with a refrigeration section and a combined refrigeration and heating section. This unit remains permanently installed in a fixed location, such as a hospital wards. The trolley is connected to this unit during storage and / or reheating of meals to be served hot. A disadvantage is the high energy consumption required for heating the food.

[0005] FR 2 775 886 A1 describes a tray intended for carrying dishes. A first zone of the tray is designed to heat the dishes, and thus the food contained therein, by contact from below with a heating plate.

[0006] The invention is therefore based on the objective of creating a carrying device for food for the rapid and energy-efficient heating or tempering of food, which makes it possible to efficiently heat and / or cool prepared food to the intended temperature regardless of location.

[0007] The problem is solved by a food carrying device with the features of claim 1. Advantageous embodiments are the subject of the dependent claims relating thereto.

[0008] The food carrying device according to the invention comprises a support containing an upper surface and a lower surface. Food and / or food containers can be placed on the upper surface. The carrying device has at least one thermal zone for transferring heat energy between the lower and upper surfaces. For this purpose, the thermal zone is made of a thermally conductive material. The thermal zone extends at least from the upper surface surrounding the thermal zone to the lower surface of the carrying device surrounding the thermal zone. The lower surface of the thermal zone can be structured to absorb the introduced heat energy.

[0009] The food carrier with the thermal zone enables particularly energy-efficient heating or cooling of food placed on the thermal zone. A key advantage is that the heat or cold is absorbed extremely effectively by the structured lower surface and transported to the upper surface where the food is located.

[0010] The thermal zone of the food carrier is preferably made of a metal, particularly preferably of an aluminum alloy. The thermal zone can also be made of a thermally conductive plastic. The thermally conductive plastic used for the thermal zone preferably has a thermal conductivity of 5 W / mK to 20 W / mK, particularly preferably a thermal conductivity of 10 W / mK to 20 W / mK, and further, particularly preferably, a thermal conductivity of 15 W / mK to 20 W / mK.

[0011] A thermal zone made from one of the above-mentioned materials is particularly advantageous because it provides low-loss transport of heat and cold energy.

[0012] The thermal zone is preferably designed to be in direct contact with the food container. This direct contact between the thermal zone and the food container advantageously enables particularly good thermal coupling. This good thermal coupling ensures that the heat or cold available in the thermal zone is transferred to the food container, and thus to the food being tempered or heated, with minimal loss.

[0013] The structured lower surface of the thermal zone of the carrying device for transporting food preferably has a lamellar shape or a wave structure.

[0014] The preferred lamellar or corrugated structure of the lower surface of the thermal zone advantageously increases the surface area. This increased surface area effectively absorbs the supplied heat or cold energy. The corrugated structure also facilitates easy cleaning of the support structure, particularly in the thermal zone area.

[0015] Preferably, the structured surface of the thermal zone is shaped such that a temperature-controlled airflow directed onto it is guided in a predetermined direction. Guiding the temperature-controlled airflow advantageously produces a turbulence-free airflow, which generates a uniform heat distribution within the thermal zone.

[0016] The carrying device preferably has at least two raised sections on its lower surface. These raised sections are dimensioned such that they extend beyond the structured surface of the thermal zone. This advantageously allows the carrying device to be placed on flat surfaces. The raised sections prevent heat loss through direct contact between the thermal zone and the surface on which it is placed.

[0017] The thermal zone preferably has a one-piece molded rim that is embedded between the upper and lower surfaces of the support. This one-piece molded rim advantageously transfers the loads caused by the weight of the food placed on the thermal zone into the support. This prevents the thermal zone from detaching from the support.

[0018] The carrying device preferably has a tapered receiving area. This tapered receiving area is designed to pass through a thermal partition. The tapered receiving area extends along an insertion direction into a system for tempering or heating food. The tapered receiving area for the thermal partition advantageously prevents airflow between the areas divided by the partition. This prevents heat exchange between the areas of the carrying device separated by the partition. Preferably, the carrying device includes a holder for a label and / or an information card. This advantageously allows information about the food and the person to whom the carrying device is assigned to be attached to the device.

[0019] The holder is preferably positioned on the carrying device in a front edge area such that the labeling and / or information card is legible when the carrying device is inserted into the food temperature control system. This makes it particularly advantageous to quickly locate the required carrying device within the food temperature control system and thus avoid significant temperature changes in the food.

[0020] The holder is preferably designed such that the labels and / or information card are legible when aligned at an angle of 30° to 50°, and preferably 40° to 45°, to the upper surface of the carrying device. This orientation makes it particularly advantageous to read the information attached to the carrying devices at virtually any level within the food temperature control system.

[0021] The holder and support of the carrying device are preferably manufactured as a single piece. This one-piece design makes the carrying device particularly easy to manufacture. Furthermore, the one-piece design allows for particularly easy cleaning of the carrying device and holder.

[0022] Exemplary embodiments of the invention are described below with reference to the drawing. The drawing shows: FIG. 1: An embodiment of a system according to the invention for tempering or heating food; FIG. 2: An interior view of the system for tempering or heating food with two chambers according to an embodiment according to the invention; FIG. 3a: An embodiment of a food carrying device according to the invention; FIG. 3b: An embodiment of a food carrying device according to the invention with a tapered receiving area for a partition; FIG. 4: A sectional view of the carrying device with a recessed thermal zone according to an embodiment that is not part of the invention. FIG. 5: A sectional view of the carrying device with two protrusions on its lower surface according to an embodiment according to the invention; FIG. 6: An enlarged sectional view of a thermal zone with an integrally formed edge in the carrying device according to an embodiment according to the invention; FIG.FIG. 7a: a sectional view of a thermal zone with a triangularly structured lower surface according to an embodiment of the invention; FIG. 7b: a sectional view of a thermal zone with a wave-shaped structured lower surface according to an embodiment of the invention; FIG. 7c: a sectional view of a thermal zone with a lamellarly structured lower surface according to an embodiment of the invention; and FIG. 7d: a thermal zone with an arcuately arranged structure on its lower surface according to an embodiment of the invention.

[0023] FIG. 1 Figure 1 shows an example of a system 1 for tempering or heating food. The system is enclosed by a box-shaped housing 35 belonging to the system. This housing consists of at least outer side walls, an outer rear wall, an outer bottom, an outer lid, and a door 36. Besides the box shape, the housing 35 can also be designed in shapes that, for example, allow integration into a means of transport.

[0024] To minimize temperature exchange between the interior and exterior of the housing, the housing is constructed with insulation. In this example, the housing elements described above are designed in a sandwich structure. A first and a third layer form the outer and inner surfaces of the housing, respectively. An insulating layer is positioned between these first and third layers. This insulating layer consists of a foamed plastic, mineral wool, or, for specific requirements, a nearly vacuum-free space.

[0025] The system for tempering or heating food further comprises at least one chamber 2 for accommodating several food support devices 20 according to the invention. This chamber 2 is arranged within the housing. Within the chamber 2, the support devices 20 are arranged vertically one above the other, each forming a horizontal surface. The support devices 20 are spaced apart. The distance between the support devices is at least large enough to prevent the food or food containers located in the system and arranged on the support devices 20 from coming into contact with the support device 20 arranged above them.

[0026] The system includes retaining devices 3 to accommodate the food carrying devices in the vertical manner described above. These carrying devices 20 are arranged in the space 2 for receiving the carrying devices. The retaining devices 3 consist of ledges on which the carrying devices 20 rest in such a way that a predetermined vertical position is maintained. The retaining devices 3 can also be designed as rails. This prevents the carrying device 20 from tipping over if it is not fully inserted into the space 2.

[0027] In the exemplary embodiment, space 2, which houses the support devices 20, is subdivided into at least two chambers 4, 37. The in FIG. 1 The two chambers 4, 37 shown each extend to at least one side wall 5. The at least one side wall 5 is spaced apart from the housing 35. As shown in this embodiment, the support devices 20 extend over the two chambers 4, 37.

[0028] Each of the two chambers 4 and 37 can be independently temperature-controlled. For example, food items in the first chamber 4 can be heated while another item in the second chamber 37 is simultaneously cooled. To achieve this, chambers 4 and 37 are thermally insulated from each other by a partition 6. This partition is constructed of a plastic with a particularly low thermal conductivity or an insulating layer system. The layer system comprises a first and a third layer, which form the outer surfaces of the partition 6. An insulating layer is located between these outer surfaces. This insulating layer consists of a foamed plastic, mineral wool, or, for special requirements, an almost completely airtight space.

[0029] Alternatively, docking a receiving vehicle to a docking station is also conceivable. It is also possible to cool the area to be heated first. In this case, the cooling unit of the refrigeration system can be used for the area to be cooled.

[0030] FIG. 2 Figure 1 shows an interior view of the example of system 1 for tempering or heating food 24 with two chambers 4, 37. The direction of view corresponds to the direction in which the support devices 20 according to the invention are inserted into system 1.

[0031] Retaining devices 3 for the carrying devices 20 according to the invention are attached to the side walls 5 and are designed, for example, as rails. The carrying devices 20 are inserted into the retaining devices 3 from the front of the system 1. Designing the retaining devices 3 as rails ensures that the carrying devices according to the invention cannot tip out of the retaining devices, even if they are only partially inserted.

[0032] A partition wall 6 is provided for the thermal separation of the two chambers 4 and 37. FIG. 2 It is clearly evident that the partition 6 is interrupted in the area of ​​the support devices 20 according to the invention in order to allow the support devices to be inserted. The inserted support devices 20 according to the invention extend through the interruptions in the partition 6. The slots in the partition 6 created by the interruptions can contain sealing elements. The sealing elements then serve to prevent an airflow between the chambers 4, 37 with different temperature levels.

[0033] In the FIG. 2 In the example shown, the left chamber 4, separated by the partition 6, is intended for heating food 24. Three fans 38 are arranged on the inner rear wall 40 (see also FIG. 2 ). With the help of the fans 38, an airflow to be heated (109 from FIG. 2 ) is generated. In this example, a heat generation device 30 located between the housing 35 and the left side wall 5 serves as the heat source. The heat generation device 30 contains three heating units 31 in this example. The three heating units heat the airflow passing by.

[0034] The hot airflow is directed via outlet openings 11, 11-1, 11-2 ... 11-10 onto a lower surface of each of the support devices 20. The outlet openings are designed to ensure optimal airflow to the area of ​​the respective support device 20 to be heated. For example, outlet openings 11-1, 11-8, and 11-9 are designed as short, tubular elements with an end beveled towards the support device 20. Outlet openings 11-2, 11-4, 11-5, and 11-6 are designed, for example, as long, tubular elements with an end beveled towards the support device 20, thus achieving targeted, localized heating of the respective support device 20. Another suitable shape for outlet openings 11-3, 11-7, and 11-9 is an arc-shaped design.Furthermore, box-shaped outlet openings, for example, are suitable for directing the hot airflow over a larger area of ​​the support device 20 according to the invention. The outlet openings can also be realized by means of louvers in the side wall 5. The design of the outlet openings is not limited to the shapes described above.

[0035] In this example, the right chamber 37 of system 1 is designed to cool the food 24 contained therein. To generate the cooling airflow 10, four fans 39 are provided as an example. Furthermore, a refrigeration unit 41 is provided, the heat exchanger of which is arranged between the housing 35 and the right side wall 5. The resulting cold airflow is directed, as already described, through a gap between the door 36 and the side wall 5 towards the support structures. However, it is also possible to provide outlet openings corresponding to those of the left chamber 4.

[0036] In this example, a left pressure sensor 110 is provided in the left chamber 4. This pressure sensor measures a negative pressure in the left chamber 4 generated by the fans 38. This negative pressure in the left chamber 4 is created by the airflow generated by the fans 38 towards the outlet openings 11-1 ... 11-10. The right chamber 37 has a right pressure sensor 112, which measures a negative pressure in the right chamber 37 generated by the fans 39. The left pressure sensor 110 and the right pressure sensor 112 are connected to a pressure control unit 111. Furthermore, the pressure control unit is connected to each of the fans 38 in the left chamber 4 and each of the fans 39 in the right chamber 4, with these connections being used to control the rotational speed of the fans 38 and 39. The pressure control unit 111 compares the vacuum measured by the left pressure sensor 110 and the right pressure sensor 112.If the pressure control unit 111 detects a pressure difference between the negative pressure of the left chamber 4 and the right chamber 37, the speeds of the fans 38 and 39 are controlled so that the pressure difference is largely zero.

[0037] To simplify pressure control, for example, the fans 38 of the left chamber 4 are operated at a constant speed. The resulting negative pressure in the left chamber 4 is measured by the left pressure sensor 110. The value measured by the left pressure sensor 110 is used as a reference value in the pressure control unit 111. The speed of the fans 39 of the right chamber 37 is then regulated so that the value measured by the right pressure sensor 112 corresponds to the reference value. This control ensures that the pressure conditions in the left chamber 4 and the right chamber 37 are nearly identical. Therefore, it is possible to omit a seal between the partition 6 and the support structure 20 without any temperature equalization between the left chamber 4 and the right chamber 37.

[0038] In another example, the reference variable can also be provided by the pressure in the right chamber 37. Pressure equalization is then controlled by the fans 38 of the left chamber 4. Other control systems are also conceivable, in which each chamber has a separate control system with a common reference variable.

[0039] FIG. 3a Figure 1 shows an embodiment of the food carrying device 20 according to the invention. The carrying device 20 comprises a support 21 and at least one thermal zone 25. In this embodiment, only one thermal zone 25 is shown. The number of thermal zones 25 is not limited. The thermal zone 25 can also extend over the entire area to be heated. The size of the thermal zone 25 is designed such that it occupies the entire partial area of ​​a chamber 4, 37 belonging to the thermal zone 25. The upper surface 22 of the carrying device 20 is designed so that food and / or food containers 24 can be placed on it. The shape of the thermal zone 25 is not limited to a circular shape. The thermal zone 25 can also have an oval shape, a rectangular shape, or any other shape.

[0040] FIG. 3b Figure 1 shows a further embodiment of the food carrying device 20 according to the invention. In this embodiment, the carrier 21 has a tapered receiving area 44 for the dividers, a holder 43 for labels and / or an information card. Labels and / or information cards containing personal data, including all necessary information about the food or the recipients, can be held in the holder. To improve readability, the holder is preferably designed so that the labels and / or the information card are attached at an angle of approximately 45° to the upper surface 22.

[0041] The holder 43 is arranged on the support structure at its front edge so that the labeling and / or information card is legible when the support structure is inserted into the food tempering system 1. Furthermore, the holder 43 is positioned at a distance from the side edges and / or a receiving area 44, which in this embodiment is tapered, for the partition 6 of the support structure 20. In other embodiments, the receiving area can be raised or flush with the lower surface 23 and the upper surface 22 of the support structure 20. The distance of the holder 43 from the side edges ensures that the support structure 20 can be inserted into the food tempering system 1 without obstruction. In this embodiment, the holder 43 and the support structure 21 are formed as a single piece. The holder 43 can also be attached separately to the support structure 21 by snapping, screwing, and / or gluing.

[0042] In FIG. 3b A thermal zone 25 with a circular shape is shown. The circular shape is dimensioned such that it is larger than the diameter of the food container. The shape of the thermal zone 25 is not limited to a circular shape. The thermal zone 25 can also have an oval shape, a rectangular shape, or any other shape. In further embodiments, the size of the thermal zone 25 can be dimensioned such that the thermal zone 25 extends over the entire area of ​​a respective sub-area. This respective sub-area is limited by the lateral edges of the support device 20 and the tapered receiving area 44 for the partitions. The size of the thermal surface 25 in this sub-area can also be smaller, corresponding to the size of the food containers 24 used.

[0043] The thermal zone 25 serves to transport heat energy between the lower surface 23 and the upper surface 22 of the support structure 20. For this purpose, the thermal zone 25 consists of a thermally conductive material.

[0044] The best heat transfer in Thermozone 25 is achieved with a metal. If Thermozone 25 is made of metal, it is preferably constructed from an aluminum alloy. A metal Thermozone 25 offers good thermal conductivity at a low weight and is resistant to chemicals such as those found in food or used for cleaning purposes. Another suitable metal group is food-grade stainless steel. This has a slightly lower thermal conductivity and a higher weight. The advantages of using food-grade stainless steel include its high corrosion resistance and almost complete resistance to acidic and alkaline cleaning agents.

[0045] Thermozone 25 can also be made of a thermally conductive plastic. Suitable plastics include, for example, those based on a short-chain polyamide (PA 6), a long-chain polyamide (PA 12), a polypropylene (PP), a polyphenylene sulfide (PPS), or a polyurethane (PUR). These plastics are modified with additives to adjust their thermal conductivity to values ​​of 5 W / mK to 20 W / mK, preferably 10 W / mK to 20 W / mK, and particularly preferably 15 W / mK to 20 W / mK.

[0046] FIG. 4 Figure 1 shows a sectional view of the carrying device with a recessed thermal zone according to an embodiment that is not part of the invention. For the transfer of heat energy between the lower surface 23 and the upper surface 22, the thermal zone 25 extends at least from the upper surface 22 surrounding the thermal zone to the lower surface 23 of the carrying device 20 surrounding the thermal zone. To further improve heat transfer, the thermal zone 25 is preferably designed to be in direct contact with the food container 24.

[0047] As in FIG. 4 As can be seen, the thermal zone 25 is preferably structured on its lower surface 26 to increase its surface area for absorbing the introduced heat energy. The thermal zone is integrated into the support 21 in such a way that the raised areas of the structured surface 26 are flush with the lower surface 23 of the support. This prevents a support device 20 placed on a flat surface from wobbling.

[0048] FIG. 5 Figure 1 shows a sectional view of the support device 20 with two protrusions 27, on the lower surface of which 23 are formed according to the invention. Here, the thermal zone is integrated into the support 21 such that the recessed areas of the structured surface 26 are flush with the lower surface 23 of the support, and the raised areas project beyond the lower surface 23 of the support. To ensure stability on a flat surface, the two protrusions 27 on the lower surface of the support device 20 are dimensioned to project beyond the raised areas of the structured surface 26 of the thermal zone. Such a support device 20 enables further improved heat transfer. Furthermore, the support device 20 can be placed securely on many uneven surfaces.

[0049] FIG. 6 Figure 1 shows an enlarged sectional view of a thermal zone 25 with an integrally formed rim 28 in the support structure 20 according to an embodiment of the invention. The integrally formed rim 28 is embedded in the support structure 21 between the upper surface 22 and the lower surface 23 of the support structure. The integrally formed rim 28 of the thermal zone is completely enclosed by the material of the support structure 21 to the extent that it projects into the support structure 21. The embedded rim 28 significantly increases the mechanical load-bearing capacity of the thermal zone 25. This allows even heavy foods and / or heavy food containers 24 to be placed on the thermal zone. This prevents the weight of the food or food containers 24 from pushing the thermal zone downwards out of the support structure 20.

[0050] In FIG. 7a A lower surface 26 of the thermal zone, structured in a triangular cross-section according to an embodiment of the invention, is shown in a sectional view. The triangular structure increases the surface area and thus improves heat transfer. Such a structure can be produced particularly easily by machining methods. Other manufacturing methods for such a structure include extrusion or injection molding.

[0051] In FIG. 7b A further embodiment shows a lower surface 26 of the thermal zone 25 with a wave-like cross-section. The wave structure is characterized by its particularly easy cleaning. This structure has no corners or edges. Therefore, it is impossible for contaminants to become trapped in the structure. Suitable manufacturing methods include, for example, extrusion or injection molding.

[0052] If special requirements are placed on the transfer of heat energy, the in FIG. 7c The illustrated thermal zone 25 features a lower surface 26 with a lamellar cross-section. Depending on the dimensions of the lamellae, a very large surface area can be generated here. With increasing surface area, the absorption capacity for heat energy from a flowing air stream also increases.

[0053] The structures of the lower structured surfaces 26 of the thermal zone are not limited to triangular, wave, or lamellar geometries. Any other suitable structures can be applied to increase the surface area.

[0054] FIG. 7dFigure 25 shows a thermal zone with an arc-shaped structure on its lower surface 26 according to an embodiment of the invention. The arc shape is adapted to the flow conditions between the outlet openings for the tempered airflow and the intake fan. This ensures uniform heat distribution and optimal heat energy transfer. Optimal heat distribution is achieved through a low-turbulence airflow, which is supported by the arc-shaped structure. The arc-shaped structure guides the airflow from the outlet openings towards the fan in a streamlined manner, thus preventing turbulence. If turbulence is not avoided and a laminar airflow is not preferred, areas of differing temperatures occur, resulting in uneven heating of the food.

Claims

1. Supporting device (20) for food, having: a support (21) which has an upper surface (22) and a lower surface (23), wherein food and / or food containers (24) are able to be brought onto the upper surface (22), wherein the supporting device (20) has at least one thermal zone (25) for transport of thermal energy between the lower surface (23) and the upper surface (22), wherein the thermal zone (25) is formed from a thermally conductive material, wherein the thermal zone (25) extends at least from the upper surface (22), which surrounds the thermal zone, to the lower surface (23), which surrounds the thermal zone, of the supporting device (20), characterized in that the thermal zone (25) is formed with structuring on the lower surface (26) in order to absorb the thermal energy introduced, wherein low regions of the structured surface (26) terminate flush with the lower surface (23) of the support (21) and raised regions project beyond the lower surface (23) of the support (21), and wherein the supporting device has on its lower surface (23) at least two elevations (27) which project beyond the raised regions of the structured surface (26) of the thermal zone (25).

2. Supporting device (20) according to Claim 1, wherein the thermal zone (25) is composed of a metal, preferably an aluminium alloy, or a thermally conductive plastic having a thermal conductivity of 5 W / mK to 20 W / mK, preferably having a thermal conductivity of 10 W / mK to 20 W / mK, particularly preferably having a thermal conductivity of 15 W / mK to 20 W / mK, and / or wherein the thermal zone (25) is in direct contact with the food container (24).

3. Supporting device (20) according to Claim 1 or 2, wherein the structured lower surface (26) has the form of lamellae or has a wave structure.

4. Supporting device according to one of Claims 1 to 3, wherein the structured surface (26) is shaped in such a way that a temperature-controlled air stream directed onto it is diverted into a predetermined direction.

5. Supporting device according to one of Claims 1 to 4, wherein the thermal zone (25) has an edge (28) which is formed in one piece thereon and which is embedded between the upper surface (22) and the lower surface (23) of the support (21).

6. Supporting device according to one of Claims 1 to 5, wherein the supporting device (20) has a tapered receiving region (44) which is formed to pass through a thermal partition wall (6), wherein the tapered receiving region (44) extends along a push-in direction into a system (1) for temperature control or heating of food.

7. Supporting device according to one of Claims 1 to 6, wherein the supporting device (20) has a holder (43) for receiving a label and / or an information card.

8. Supporting device according to Claim 7, wherein the holder (43) is arranged on the supporting device (20) in a front edge region so that the label and / or information card is legible when the supporting device (20) has been pushed into the system (1) for temperature control of food.

9. Supporting device according to Claim 7 or 8, wherein the holder (43) is arranged in such a way that the labels and / or information card are / is legible oriented at an angle of 30° to 50°, preferably of 40° to 45°, to the upper surface (22) of the supporting device (20).

10. Supporting device according to one of Claims 7 to 9, wherein the holder (43) and the support (21) are designed in one piece.