LUNCHBOX

Description

[0001] The present invention relates to a lunch box for storing, transporting and heating food in solid, pasty or liquid form, in particular food prepared for consumption.

[0002] Lunch boxes for storing and transporting food for consumption on the go or at work have been in use for many decades. Two-piece containers made of metal or plastic with a hinged lid or a removable lid, with a large bottom section for a main meal, or with an overlapping, approximately equal-sized top and bottom section for bread, etc., are well known.

[0003] In retail, one- or two-piece disposable containers, mostly made of foam, are used, mostly to offer ready-to-eat portions of fruit, vegetables or ready meals.

[0004] DE 202013010997 U1 discloses a folding container designed to prevent objects from falling out when the upper shell is opened. The folding container consists of an upper shell and a lower shell, which are hingedly connected to one another along one long side. A snap-in closure is provided on the opposite long side. The upper shell is provided with an upper inner lid and the lower shell with a lower inner lid, so that the two interior volumes can be closed completely and independently of one another. On the side opposite the hinge point for the inner lids, a lid closure in the form of a snap-in lug is provided in each of the upper shell and the lower shell.

[0005] Another plastic lunch box for storing food is disclosed in DE 10157494 B4. It consists of a container with side walls, a base, and a molded lid. An additional compartment is located on the underside of the container, which can be closed with an additional lid. The lid and additional lid are connected to the container via a film hinge.

[0006] Another container with a lid for storing food contains an exothermic heating element according to EP 0412159 B1. The container comprises an upper inner container for the materials to be heated and a lower inner container located below it, which contains water and an exothermic material. The lower inner container is provided with a cover. The container further comprises an externally operable device for contacting the exothermic material with the water. The cover of the lower inner container is vapor-permeable but impermeable to the exothermic material.

[0007] The water and the exothermic material are in separate bags that can be torn open separately.

[0008] Such a solution is complex and only suitable for stationary operation.

[0009] A portable lunch box is known from WO 2011 / 112284 A1. The lunch box comprises an upper tray and a lower tray, which are hingedly connected to one another along one long side, with a closure provided on the opposite long side. Additionally, a pivoting divider tray is provided, forming an upper and a lower compartment for food. A tray can be inserted into the lower compartment, which can also be filled with a cooling or heating gel to temporarily maintain a specific temperature for food.

[0010] GB 2056264 A shows a conventional lunch box for keeping food warm, for use in kitchens or catering, with a hinged lid that can be locked using a safety catch. A power connection is undoubtedly provided, with the heating element being a conventional heating wire that only heats the food from below.

[0011] Another heated lunch box has an inner container that can be closed with a removable lid in the lower tray. The upper tray has recesses for cutlery. The lower tray is equipped with a power connection for a heating element located in the lower tray, which is housed in an insulating layer of foam. The heating capacity of the food in the inner container is limited and time-consuming.

[0012] US 2015 / 0245723 A1 discloses drinking vessels that can be actively heated or cooled. These have a cylindrical outer shell with a closed bottom in the form of a partition. The upper surface can be closed with a lid. A heatable, double-walled cylinder (inner cylinder) is provided within the outer shell.

[0013] The power supply is provided by integrated batteries in a false floor beneath the partition, which also contains a battery control system. Document CN 105 852 370 B discloses a lunchbox according to the preamble of claim 1.

[0014] The invention is based on the object of providing a lunch box which overcomes the disadvantages of the prior art and which is easy to handle.

[0015] The object is achieved according to the invention with a lunch box having the features of patent claim 1.

[0016] According to the invention, the lunchbox comprises a lid and a housing that can be connected to each other. It has an electric heating element, a device for supplying power and controlling the power supply and operating modes, and a sensor arrangement for controlling the temperature of the heating element.

[0017] Preferred embodiments of the invention are disclosed in the dependent claims.

[0018] The lunchbox according to the invention is suitable for storing, transporting, heating, or cooling food in solid, pasty, or liquid form, especially ready-to-eat food. The food can also be contained in flat plastic bags, glass containers, or the like.

[0019] The lunchbox according to the invention is therefore versatile. It can be used for food for adults, children, or babies.

[0020] The invention will be described in more detail below in an exemplary embodiment with reference to a drawing. In the drawing, the Fig. 1 : a lunch box according to the invention; Fig. 2 : the lunch box after Fig. 1 in a different representation; Fig. 3 : a further design of the lunchbox according to Fig. 1 ; Fig. 4 : the lunch box after Fig. 2 in a different representation.

[0021] A lunchbox 20 according to the invention ( Fig. 1 , 2 ) In the example, it comprises a lid in the form of an upper shell 1 and a housing in the form of a lower shell 2, each made of plastic and / or metal, for example, polypropylene (PP), with the upper shell 1 functioning as a removable lid. The upper shell 1 and the lower shell 2 are connectable to one another. In the example shown, this is done by means of a locking fastener 4 (or snap fastener) on one long side of the lunchbox, with locking cams 14 also being provided on the opposite long side.

[0022] Instead of the snap fastener 4, a film hinge can also be provided (molded on one long side) or a swivel hinge which is attached to the upper and lower shell, etc. This would allow the upper shell 1 to be opened.

[0023] Upper shell 1 and lower shell 2 lie flat against each other in a parting plane and, if necessary, overlap with an overhang of the upper shell 1.

[0024] A power connection socket 5 is provided on a side wall of the lower shell 2. This socket can be designed in the form of a conventional plug or as a USB port to establish a connection to a charging station 21 or a power supply unit. Alternatively or additionally, such a power connection socket 5 can also be provided in the upper shell 1. Additionally or alternatively, flat rechargeable batteries can also be arranged in the lower shell 2.

[0025] On the opposite side wall of the lower shell 2, an LED 6 is arranged as a status indicator (heating) and, if applicable, as a temperature indicator 23. A pressure equalization element (not specified in more detail) for the extraction of warm air and water vapor can also be installed in the upper shell 1.

[0026] The peripheral edge areas of the upper shell 1 and lower shell 2 are designed in such a way that they can function as a seal.

[0027] The lunchbox 20 may further include at least one insertable or removable tray 9 for holding food to be heated or cooled.

[0028] The shell 9 is made, for example, of an aluminum material or stainless steel with a thickness of 0.5 mm and is arranged in the lower shell 2. The shell 9 has an L-shaped angled edge region 8, wherein a seal 10 can be arranged between the edge region 8 and the lower shell 2.

[0029] The bowl 9 can also be flat, for example, to hold liquids in flat dispenser bags with a capacity of 180 ml. This allows breast milk to be warmed sterilely and without a water bath and kept warm at, for example, 37°C, much faster than in a bottle.

[0030] If the lunch box is designed accordingly, it would also be possible to cool the dispenser bag or similar before heating, for example using a Peltier element.

[0031] In a manner not shown, the lower shell 2 can also be designed with higher walls, so that several shells 9 can be arranged one above the other.

[0032] The bowl 9 can be easily removed from the lower bowl 2 for cleaning or other purposes.

[0033] In another embodiment, a fixed arrangement of the shell 9 in the lower shell 2 would also be possible, for example by means of an adhesive connection or the like.

[0034] Insertable or fixed shells 9 without thermal insulation are also possible.

[0035] The bowl 9 and the lower bowl 2 are adapted to each other in their design and shape, or rather, coordinated with each other. Thus, differently shaped bowls 9 can be used or inserted into the lower bowl 2. Thus, the height of the lunchbox 20 can be adjusted to the height of the bowl 9, so that both tall and flat lunchboxes can be produced.

[0036] A thermal insulation 11, for example made of PUR integral foam, can be provided between the inner wall of the lower shell 2 and the shell 9. A sensor-controlled electric heating element 12 with a heating foil, in this example, is also mounted between the insulation and the shell 9. This allows for precise temperature control of the heating (or cooling). However, the thermal insulation 11 could also be formed from a Keraguss S molded part, an aerogel molded part, an EPS molded part, air, or vacuum.

[0037] Thermal insulation 11 and the heating foil can cover the bottom area of ​​the shell 9 or at least partially enclose the side walls of the shell 9.

[0038] In addition, the inside of the upper shell 1 can also be provided with such thermal insulation 11 and a heating element 12.

[0039] The connection between the power connection socket 5 and a control electronics 13 as well as to the heating element 12 is established via cable connections not shown.

[0040] The control electronics 13 is arranged, for example, on a flat circuit board, which in turn is plugged into the inner wall of the lower shell 2 to save space. The control electronics 13 contains the electronic control system, a safety circuit, and a load switch. The electronic control system 13 should include at least an analog or digital temperature sensor 30, a heating switch (thermoswitch 31), and the output for the LED 5 and the temperature indicator 23.

[0041] The electronic control can also allow different heating modes, for example bottom and / or top heat.

[0042] The electronic control 13 can also communicate with an external control unit 22, for example a smartphone (24), and be controlled via an app.

[0043] Alternatively or additionally, haptic buttons, sensor buttons and / or a display can be provided on the Lunchbox 20 itself in order to be able to make mode and temperature settings on it.

[0044] The sensors 30, 31 are preferably arranged near the outer edge of the shell 9 ( Fig. 1 , 2 ) or directly attached to the edge of the bowl.

[0045] Furthermore, an optical sensor, a camera or a thermal imaging camera can be arranged, advantageously in the upper shell 1 above the shell 9, with which the food can be monitored.

[0046] In a further embodiment, the heating element 12 can also be designed in zones, with each zone being assigned a sensor 30, 31. This enables heating (cooling) to different target temperatures in the individual zones.

[0047] In this example, heating element 12 consists of a metallic heating foil embedded between two silicone layers for electrical insulation. However, Kapton heating foils, polyester heating foils, ceramic heating elements, or contact heating elements can also be used.

[0048] The power supply can range from 5V to 240V, including standard tolerances. For example, with 5V or 12V DC, no special safety measures would be required. For a 230V AC version, the shell 11 would either have to be grounded or the aforementioned double electrical insulation would have to be applied.

[0049] When choosing the connection variants, the current carrying capacity, temperature and resistance to cleaning agents must be taken into account.

[0050] The electrical connections are preferably waterproof.

[0051] The heating foil's heat output should be at least approximately 20-150W to allow food to be heated to approximately 160°C if necessary. Depending on the food, lower or higher heat outputs may be permissible, although the values ​​also depend on whether a heating element is installed only in the lower tray 2 or also in the upper tray 1. If a heating element is installed in the upper tray 1, its heat output is normally lower than in the lower tray 2.

[0052] To heat a food item, the lunchbox 20 is connected to the power source and the start button, LED 6, is activated. The LED 5 signals the heating process by illuminating it for a period of time preset in the control electronics 12. Furthermore, the heating process can be displayed as a colored temperature indicator 23 using another LED.

[0053] After the heating time has elapsed, the control electronics switches off the heating foil and LED 5 goes out.

[0054] Other operating modes can be programmed using control unit 22 and the app. List of reference symbols:

[0055] 1Top shell 2Bottom shell 3Side wall 4Locking lock 5Power connection socket 6LED 7Screw 8Edge area 9Shell 10Seal 11Insulation 12Heating element 13Control electronics 14Locking cam 20Lunchbox 21Charging station 22Control unit 23Temperature indicator 24Mobile phone 30Analog sensor 31Thermal switch

Claims

1. Lunchbox for storing, transporting and heating food in solid, pasty or liquid form, in particular food prepared for consumption, comprising a lid and a housing that can essentially be connected to one another, wherein it has an electric heating element (12), a device for the power supply and for controlling the power supply and operating modes and a sensor arrangement for temperature control of the heating element (12), characterized in that the sensor arrangement has at least one analogue or digital sensor (30) and at least one thermostatic switch (31).

2. Lunchbox according to claim 1, characterized in that the heating element (12) is controlled in analogue and / or digital manner and / or is sensor-controlled.

3. Lunchbox according to claim 1 or 2, characterized in that the sensor arrangement has an optical sensor.

4. Lunchbox according to one of the claims 1 to 3, characterized in that a shell (9) can be inserted into the housing or is permanently arranged as a lower shell (2).

5. Lunchbox according to one of the claims 1 to 3, characterized in that a shell (9) for receiving the food to be heated can be arranged in the housing and is assigned a thermal insulation (11).

6. Lunchbox according to one of claims 4 or 5, characterized in that the optical sensor is preferably arranged in the lid designed in the form of a top shell (2) and the at least one sensor (30, 31) for controlling the heating element (12) is arranged close to the shell (9) or on the outside of the shell (9).

7. Lunchbox according to one of the claims 1 to 6, characterized in that an integrated battery and / or a power connection socket (5) is / are arranged on the lower shell (2) for the power supply.

8. Lunchbox according to one of the claims 1 to 7, characterized in that it can be controlled and operated offline on the lunch box itself by means of electronic control and / or online by means of an external control device (22) and optionally the temperature of the food is determined.

9. Lunchbox according to one of the claims 1 to 8, characterized in that it can be controlled via Bluetooth or by means of an app via a mobile phone (24) or a cloud application.

10. Lunchbox according to one of the claims 1 to 9, characterized in that the lid and the casing can be connected to one another in a force-fitting manner in a resting position or can be connected to one another in a hinged manner on one longitudinal side, a closure being provided on the opposite longitudinal side.

11. Lunchbox according to one of the claims 4 to 10, characterized in that the shell (9) is provided with a peripheral edge region (8) in the region of a parting plane between the lid and the housing, with which a sealing element is associated.

12. Lunch box according to one of the claims 1 to 11, characterized in that a pressure equalization element is mounted in the lid.

13. Lunchbox according to one of the claims 5 to 12, characterized in that the thermal insulation (11) and the heating element (12) extend at least over the base of the shell (9) and preferably at least partially enclose the side walls of the shell (9).

14. Lunchbox according to one of the claims 1 to 13, characterized in that the lid is also provided with thermal insulation (11) and an electric heating element (12).

15. Lunchbox according to one of the claims 1 to 14, characterized in that the peripheral edge regions (8) of the lid and housing are designed to be formcorrsponding and to fulfil a sealing function.

16. Lunchbox according to one of the claims 1 to 15, characterized in that the electric heating element (12) comprises a heating foil.

17. Lunchbox according to one of the claims 1 to 16, characterized in that it can be coupled to a charging station (21) and that the charging station (21) and / or the lunch box (20) is provided with a temperature indicator (23) and / or a weight recognition device.