Thermal box

Abstract

The invention relates to a thermal box (10) for actively temperature-controlling the interior of the thermal box, comprising a cup-shaped base (12) and a lid (14) for defining the interior. The base and the lid have insulating walls. Furthermore, a device for actively temperature-controlling the interior is provided. This device includes an outer heat emitter (31) and an inner heat emitter (41). Additionally, an outer rotor (33) and an inner rotor (43) are provided. The inner and outer rotors are connected via a common drive shaft (24) to an electric motor (26), which is located within the interior.

Description

[0001] The invention relates to a thermal box for actively controlling the temperature of the interior of the thermal box. Thermo boxes of this type comprise a cup-like base body and a lid for defining the interior. The base body and the lid are essentially formed with an insulating wall.

[0002] The lid is usually hinged to the base body. A typical thermobox is known, for example, from DE 20 2021 102 922 U1.

[0003] Such thermal boxes are primarily used as coolers. They can be powered by 12 volts direct current from a vehicle power supply, but can also be powered by a wall outlet, for example, with 230 volts alternating current, using appropriate adapters (some of which are integrated). However, the problem with this type of portable cooler is that, with their current design, they often generate a relatively high level of noise. The noise emitted by the thermal box can be perceived as disturbing, especially when used in quiet environments, such as inside a building or when camping with a power supply.

[0004] US Pat. No. 4,726,193 A discloses a refrigerator / food warmer comprising an insulated food compartment and a lid. A thermoelectric heat exchanger and an air circulator are mounted in the lid, with both a heat sink of the thermoelectric heat exchanger and an air impeller of the air circulator located above and below the lid, respectively. The air impeller above the lid draws air through the corresponding heat sink to improve the temperature differential between opposite sides of the thermoelectric heat exchanger, and the air impeller below the lid forces the air of the insulated enclosure through the corresponding heat sink to condition the air hot or cold as desired and to circulate the conditioned air throughout the insulated enclosure.

[0005] US Pat. No. 5,413,166 A discloses a thermoelectric module suitable for selectively heating or cooling the interior of a container, comprising an outer heat exchanger having a plurality of spaced-apart and generally parallel undulating fins. An outer fan is disposed adjacent to the outer heat exchanger and serves to move air from the outside of the container through the spaces between the fins of the outer heat exchanger. An inner fan is disposed adjacent to an inner heat exchanger and is designed to move air from the inside of the container through the spaces between the fins of the inner heat exchanger. A motor drives the fans, which are cooled by air drawn through openings in the hub of the outer fan.

[0006] US Pat. No. 5,315,830 A discloses a modular thermoelectric assembly for maintaining the temperature in a container or enclosed structure at a desired level. The thermoelectric assembly comprises a thermoelectric device with a hot sink and a cold sink. A layer of insulating material is disposed between the hot and cold sinks. The hot sink and insulating material serve to install the thermoelectric assembly in an appropriately sized opening extending through the exterior of the container or enclosed structure. The thermoelectric device, located in the layer of insulating material, acts as a heat pump to transfer heat between the cold sink and the hot sink. An electric motor, a rotating shaft, and two coaxial propellers are supported by the assembly to assist air circulation.

[0007] The invention is therefore based on Task The idea is to provide a thermobox for actively controlling the temperature of its interior, which causes less noise emissions during operation.

[0008] This object is achieved according to the invention by a thermal box having the features of claim 1.

[0009] Preferred embodiments of the invention are specified in the subclaims, in the description as well as in the figures and their explanation.

[0010] The thermobox according to the invention has a device for actively controlling the temperature of the interior in the form of a heat and cold pump for generating a temperature difference between the interior and an exterior of the thermobox. The device for active temperature control has an outer temperature radiator directed towards the exterior of the thermobox and an inner temperature radiator directed towards the interior. In addition, the device for active temperature control has a double fan, which has an outer rotor in the area of ​​the outer temperature radiator and an inner rotor in the area of ​​the inner temperature radiator. The inner and outer rotors have a common drive shaft, which is driven by an electric motor. The electric motor itself is provided on and / or in a region of the wall facing the interior.

[0011] According to the invention, it was recognized that a significant portion of the thermal box's noise emissions is generated by the rotation of the rotors and the electric motor. However, the position and function of the two rotors are inherent to the application, as they serve to move an airflow through the respective heat radiator, enabling better heat dissipation or absorption.

[0012] Therefore, according to the invention, it is proposed to install the electric motor on and / or in a section of the wall facing the interior. This places the electric motor facing the interior. During normal use of the thermal box, it is therefore located inside the thermal box. This offers the advantage that the insulating wall dampens the noise emissions of the electric motor, and the noise escapes to a significantly lesser extent outside the thermal box.

[0013] In this way, noise emissions can be reduced using relatively simple means. Other options, such as redesigning or modifying the rotors, would be far more complex and difficult and would only lead to similar results.

[0014] According to the invention, the electric motor is integrated into the inner rotor. For this purpose, the inner rotor can have a receptacle in which the electric motor is placed. This type of integration or construction offers the advantage that no further adaptations to a conventional thermal or cooling box are necessary, since no additional space needs to be provided for the electric motor outside the rotor.

[0015] In principle, the inner rotor can be designed in any way. It is preferably designed as a rotor for a radial fan. This allows it to be positioned next to the inner heat radiator and draw in air from the front, which is then directed or blown laterally through the inner heat radiator.

[0016] The inner rotor can, for example, have blades for air movement, which are placed on a disc. The blades can extend from an outer region of the disc toward a central area of ​​the disc, leaving an area in the central area free. This means that no blades are provided there. Experience has shown that blades that do not extend completely into the central area are sufficient to enable sufficient air movement. The electric motor can then be placed in the free central area.

[0017] For optimal placement, it is preferable if the mount on the inner rotor is cup-shaped and provided in the free central area. The electric motor or its components can be inserted into this cup-shaped mount during assembly, allowing for relatively easy integration.

[0018] It is advantageous if the depth of the receptacle is equal to or less than the height of the blades of the inner rotor. In other words, the receptacle represents a cylindrical elevation on the disk in the central region, located on the side on which the blades are attached. Because the receptacle is no deeper than the height of the blades, the overall depth of the inner rotor is not increased by the design according to the invention. The receptacle can be closed on the side of the blades and open on the side of the disk facing away from the blades, so that the electric motor can be inserted there. In this way, at least individual parts of the electric motor can be connected to the cover and function as a stator.

[0019] It is preferred that a ring- or cylindrical magnet of the electric motor be firmly fixed in the cup-shaped receptacle, serving as the rotor of the electric motor. The remaining electric motor—as the stator—is located in the remaining free space of the receptacle, through which the shared drive shaft of the two rotors also extends. The stator of the electric motor is firmly connected to the axle and the base body or the cover of the thermal box, while the ring- or cylindrical magnet, which acts as the rotor, is firmly fixed in the cup-shaped receptacle.

[0020] In principle, any heat and cold pumps can be used for the thermobox according to the invention. These are preferably thermoelectric elements, in particular Peltier elements.

[0021] The device for actively controlling the interior temperature is preferably located in the lid of the thermobox. However, it can also be integrated into the sides of the base body. The only essential requirement is that the outer rotor allows a sufficiently strong airflow through the outer temperature radiator. The same applies to the inner rotor and the inner temperature radiator. In addition, it should be possible to arrange the heat and cold pump between the two temperature radiators and connect them to them in a thermally conductive manner.

[0022] The invention is explained in more detail below using schematic embodiments with reference to the figures. Fig. 1 shows a schematic view of a mobile thermal box according to the invention; Fig. 2 shows a lid of a thermal box according to the invention; and Fig. 3 shows an inner rotor on the thermal box according to the invention.

[0023] In Fig. 1A schematic representation of a thermal box 10 according to the invention is shown, which can also be referred to as a cooling box. In principle, however, the thermal box 10 can also be used to keep the interior warm.

[0024] The thermal box 10 has a base body 12 and a removable lid 14. This can—but does not have to—be hinged to the base body 12. The base body 12 is cup-shaped and can be closed with the lid 14 to enclose an interior space.

[0025] InIn this embodiment, the lid 14 contains a device for active temperature control 20, which may comprise a thermoelectric temperature control element, in particular a Peltier element. The active temperature control unit 20 is shown only in outline. The active temperature control unit 20 serves to adjust a temperature difference between the interior of the thermobox 10 and the exterior. Preferably, the interior is cooled. However, heating of the interior can also be provided.

[0026] The active temperature control device 20 receives its power, for example, from a suitable power supply that supplies it with 12 volts direct current or 230 volts alternating current. It can also be powered by a battery.

[0027] The device for active tempering 20 is described below with reference to Fig. 2 explained in more detail. Fig. 2shows a section of the cover 14. On the outside of the cover 14, an external temperature radiator 31 and an external rotor 33 are provided. In Similarly, an inner temperature radiator 41 and an inner rotor 43 are provided on the inside of the cover 14. A heat pump 22 extends between the two temperature radiators 31 and 41. This heat pump does not have to extend to the two temperature radiators 31, 41, but can also be thermally connected to them alone. A temperature difference can be created between the inside and outside by means of the heat pump 22.

[0028] The temperature radiators 31, 41 are preferably constructed of a temperature-conducting material and have cooling or radiating fins. They absorb the temperature generated by the heat pump 22 and dissipate it to the interior or exterior, respectively.

[0029] In the following, it is assumed, by way of example, that the heat pump 22 is used to cool the interior of the thermobox 10. In this case, the temperature radiator 41 is cooled, whereas the temperature radiator 31 is exposed to the corresponding heat energy generated by the cooling. To improve the radiation of the respective temperatures, an outer rotor 33 and an inner rotor 43 are provided. These draw in air—as indicated by the arrows—and blow it through their respective temperature radiators 31, 41.

[0030] An electric motor 26 is provided to drive the two rotors 33, 43. The rotors 33, 43 are connected by a common shaft 24. The electric motor 26 is located on the side of the lid 14 facing the interior of the thermal box 10.

[0031] As indicated by the thickness of the portion of the lid 14 shown here, the wall is insulated. This insulation provides both thermal insulation and noise dampening. This ensures that, when closed, the noise generated by the electric motor 26 is less likely or barely transmitted to the exterior of the thermal box 10, thus dampening the noise.

[0032] In principle, the electric motor 26 can be designed and integrated anywhere on the inside of the thermobox 10, for example in the area of ​​the lid 14.

[0033] In Fig. 3 A particularly space-saving recording option is shown. Fig. 3shows an enlargement of an embodiment of an inner rotor 43. This has a disk 46 on which rotor blades 45 are arranged. These extend from an outer region to a central region, but not into the central region. In the central region, a receptacle 44 for the electric motor 26 is provided. This can be cup-shaped. In the embodiment shown here, this receptacle 44 is closed at the top so that the electric motor 26 is inserted from below. The electric motor 26 is connected by its stator to the cover of the thermal box 10. In principle, however, another design is also possible. The electric motor 26 is connected to the drive shaft 24 of the two rotors 33, 43.

[0034] By means of the thermobox according to the invention, it is possible to significantly reduce noise emissions without, however, having to carry out a comprehensive redesign of the thermobox.

Claims

1. Thermal box (10) for active temperature control of an interior of the thermal box (10), with a cup-like main body (12) and a lid (14) for defining the interior, wherein the main body (12) and the lid (14) have an insulating wall, with a device for active temperature control (20) of the interior in the form of a heat and cold pump (22) for generating a temperature difference between the interior and an exterior of the thermal box (10), wherein the device for active temperature control (20) has an outer temperature radiator (31) directed towards the exterior of the thermal box (10) and an inner temperature radiator (41) directed towards the interior, wherein the device for active temperature control (20) has a dual fan, which in the region of the outer temperature radiator (31) has an outer rotor (33) and in the region of the inner temperature radiator (41) has an inner rotor (43), wherein the inner rotor (43) and the outer rotor (33) have a common drive shaft (24), which is driven by means of an electric motor (26), wherein the electric motor (26) is provided on and / or in a region of the wall facing the interior, and characterised in that the electric motor (26) is integrated into the inner rotor (43).

2. Thermal box (10) according to claim 1, characterised in that at least the inner rotor (43) is configured as a rotor for a radial fan.

3. Thermal box (10) according to claim 1 or 2, characterised in that the inner rotor (43) has blades (45) on a disc (46) which extend from an outer region of the disc (46) in the direction of a central region of the disc (46), wherein the central region is left open.

4. Thermal box (10) according to any one of claims 1 to 3, characterised in that the inner rotor (43) has a receptacle (44) for the electric motor (26).

5. Thermal box (10) according to claim 4 in combination with claim 3, characterised in that the depth of the receptacle (44) is the same as or smaller than the height of the blades (45) of the inner rotor (43).

6. Thermal box (10) according to claim 4 in combination with claim 3 or claim 5, characterised in that the receptacle (44) of the inner rotor (43) is designed cup-like in the central region of the inner rotor (43),7. Thermal box (10) according to claim 6, characterised in that an annular or cylindrical magnet is firmly fixed in the cup-like receptacle (44).

8. Thermal box (10) according to any one of claims 1 to 7, characterised in that a rotor of the electric motor (26) is firmly connected to the drive shaft (24).

9. Thermal box (10) according to any one of claims 1 to 8, characterised in that the heat and cold pump (22) is embodied as a Peltier element.

10. Thermal box (10) according to any one of claims 1 to 9, characterised in that the device for active temperature control (20) of the interior is provided in the lid (14) of the thermal box (10).

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