EP3209581B1 - Thermally insulated transport container comprising thermal insulation resting against the walls - Google Patents

Description

The invention relates to a thermally insulated transport container with a housing for forming a space for goods, with walls and a thermal insulation against the walls, and a wall structure of such a container. In particular, the invention relates to such an air cargo container.

Objects, foodstuffs, pharmaceuticals, biological samples, blood, blood plasma or even organs intended for transplantation are stored or transported at a suitable temperature in a suitable form in thermally insulated containers. There should be no impairment over a longer period of time and, in particular in the case of air freight, there should be no additional energy supply for additional cooling or heating. These containers are also unattended for long periods in transport and therefore equipped with means of communication for data transmission, e.g. For example: GPS, GSM for location transmission and temperature control, RFID for logistic logging, etc.

So far, containers have been used that have thermal insulation. In the simplest case, such containers are made of or with polymeric foams, such as. B. polystyrene (styrofoam). Although these foams advantageously have a low weight, they are not very durable and stable. Furthermore, the achievable thermal insulation is limited.

The use of vacuum insulation panels (VIP) is known. These panels have improved thermal insulation, but only as long as the high vacuum required within the panels can be maintained. The outer shell of vacuum insulation panels is usually formed from at least one film, which can also be coated with a metal. Both the film and in particular the connections of the film for the gas-tight closure of the panels, e.g. E.g .: in the form of sealed seams, but they are critical and leakages can occur due to mechanical stress or thermal influences, so that the vacuum conditions inside are lost. Therefore revealed DE 10 2011 015 715 A1 a wall structure with an inner wall made of a thermoplastic polymer to protect the vacuum insulation panel.

A known vacuum insulation panel consists of a pre-compressed porous bed, a porous press plate or an open-cell hard foam as a substrate, which is enveloped by a gas-tight film, the film being welded or glued after evacuation. For example, precipitated and dried silicas, silica gels, fly ash, open-celled organic-based foams such as open-celled rigid polyurethane foams or bound rigid polyurethane foam powder, as used, for example, in, serve as filling material for vacuum insulation panels DE 4 439 331 and DE 4 439 328 to be discribed. Such vacuum insulation panels are also already used in the manufacture of cold rooms, for example refrigerators or refrigerated containers, by inserting them between the outer and inner housing and foaming the remaining space between the outer and inner housing. For example, disclosed EP 0 822 379 a vacuum insulation panel fastened on a rigid plate, which is fixed on the rigid plate by a polyurethane foam applied as a liquid reaction mixture.

Other known containers require a stability-giving frame in which the multilayer walls, for. For example: made of sheet metal with glued insulation. The structure is complicated, expensive and has a high weight, which is to be avoided in particular in the case of air freight.

WO 2005/016643 A1 discloses a transport container without thermal insulation, with a housing with walls. Sandwich plastic plates are provided as walls, with a honeycomb core, which is welded to both sides with a cover layer, the honeycomb core and the cover layers being made of a thermoplastic material,

WO 2012/085212 A2 discloses a container using vacuum insulation panels (VIP) as thermal insulation, these being integrated into a box constructed from individual normal wall elements. The wall elements are not sandwich panels.

DE 696 30 193 T2 discloses a load container with walls made of sandwich plastic plates with a honeycomb core, which is welded to both sides with a cover layer, the honeycomb core and the cover layers being made of a thermoplastic material.

It is therefore an object of the invention to provide a thermally insulated transport container which is further developed compared to the prior art or to further develop details. This object is achieved by a thermally insulated transport container with the features of claim 1. Advantageous refinements are the subject of the dependent claims. Further developments are the subject of secondary claims.

The thermally insulated transport container according to the invention initially necessarily comprises a housing for forming a space for goods, that is to say the objects to be transported and cooled. The housing also has walls and a thermal insulation against the walls. According to the invention, sandwich plastic panels are now provided as walls with a honeycomb core, which is welded to both sides with a cover layer, the honeycomb core and the cover layers being made of a thermoplastic material, preferably PP. The walls are in particular a thermoplastic sandwich panel, consisting essentially of a PP (polypropylene) honeycomb core and PP cover layers, in particular glass fiber reinforced, which are homogeneously bonded to one another by melt lamination are. Such plates are e.g. For example: offered by Wihag Composites GmbH & Co. KG under the MonoPan ® brand, which are preferred here.

The use of thermoplastic material enables adjacent sandwich plastic sheets to be attached to one another by welding. These are welded in the area of the edges and corners of the housing. It is therefore possible to produce largely frameless and thus lighter transport containers. A reinforcement is provided only in the area of the door, which particularly absorbs the door load. Basically, an outside corner, inside corner, outside edge and / or inside corner protection can also be provided, which rather represents mechanical protection of the sensitive edges / corners and also serves as a foot part, guide or support surface for a better installation and / or stacking of the containers. The protection can also serve air and / or heat sealing purposes, since the insulating honeycomb structure is impaired in the area of the weld seam. In the prior art, aluminum sheets or aluminum light building boards are usually used in a stability-giving frame made of aluminum profiles. These connections are often not tight, which allows undesired heat transfer through air exchange. Sandwich plastic sheets made of thermoplastic material that are welded together enable sealing without additional sealing compound and steps. Furthermore, thermoplastics have a lower density and thermal conductivity and are permeable to radio waves. The welding is preferably carried out by fusion welding, hot air welding or plastic extrusion welding. Such plates are also easy to cut.

The transport container is constructed without a frame, the sandwich plastic panels connected to one another forming a torsionally rigid, self-supporting housing. So there is no need for a subframe, e.g. E.g .: from aluminum profiles. Therefore, no further stiffening elements are provided in addition to the sandwich plastic panels and a door reinforcement for a door.

If vacuum insulation panels are provided as thermal insulation, light, industrially manufactured components can be used which have excellent thermal insulation.

According to the invention, the walls have two layers of sandwich plastic plates in between lying, adjacent thermal insulation, on. This is the Thermal insulation, especially the sensitive vacuum insulation panels, is protected on both sides against damage and the wall is stiffened by the thermal insulation.

If a self-supporting outer housing made of welded sandwich plastic plates and a preferably also self-supporting inner housing made of welded sandwich plastic plates are preferably provided, the inner housing forming the space for goods and being arranged at a distance from the outer housing in the outer housing, the space between the inner and outer housing is filled with the thermal insulation, the inner housing can be removed as a whole or for panels for maintenance and / or cleaning purposes. Especially when using vacuum insulation panels, it is important that they are easily accessible and interchangeable or testable.

Furthermore, if the insulation is preferably fastened flatly or sectionally or point by point in the outer housing and the inner housing is also preferably inserted into the insulation, a further stiffening results from the connection of the components.

If the sandwich plastic sheets consist exclusively of thermoplastic material, preferably PP, the weldability is simplified and the weld seams improved, in particular their tightness and stability.

Alternatively, it is preferred that the one or both cover layers and / or the honeycomb core are fiber-reinforced, in particular glass or carbon fiber reinforced and / or have such a cover and / or intermediate layer. If the weldability is only slightly impaired, the stability of the walls is increased considerably with only a minimal increase in weight of the container.

The honeycomb core is preferably homogeneously bonded to the cover layers by means of melt lamination.

The suitability of the container for maintaining the prescribed temperature during long transport, e.g. For example, air freight is particularly given if the thermal conductivity of the thermal insulation is 0.002 - 0.009 W / m K.

To control the route and the transport conditions of the container according to the invention during transport, communication means, in particular mobile radio devices, RFID or other wireless transmitters / receivers, are preferably provided within the outer housing for data transmission. Because of their short range, RFID is used for logistic operators. These means of communication can e.g. For example: outside of the thermal insulation, but located inside the outer casing or simply inside the container.

There are therefore no implementations z. For example: to the antenna or sensors through the walls. The communication means preferably contain integrated sensors or are connected or connectable to them. Therefore, if necessary, the communication means as a whole can be exchanged and serviced without the need for complex cabling, which therefore cannot be accidentally forgotten. The communication means can be easily installed in the transport containers in use, so that no communication means have to be kept ready for containers that are not in use.

GPS for location transmission and sensors for temperature control are considered to be integrated sensors or sensors that can be connected or connected with the communication means. Furthermore, vacuum detectors for monitoring the air pressure in the vacuum insulation panels can also be provided as sensors.

If the door reinforcement preferably comprises a profile, in particular a frame formed from it, made of a light metal alloy, in particular aluminum, which is fastened to the outer housing and the inner housing and connects them to one another, this results in increased stability in the area of the opening for the door. The door reinforcement thus forms a door frame for inserting and receiving the door and connects and closes off the inner housing with the outer housing. The frame stiffens the PP housing, which is normally relatively soft in the area of the door opening, in such a way that opening the heavy door through the load introduction of the door into the wall-mounted hinge does not cause the housing to twist and / or the door may hang slightly crooked in the housing frame . The door reinforcement allows a weaker design of the walls and thus saves weight. It also serves to secure the door, e.g. E.g .: by means of door hinges or a lock.

Although the cooling of the container according to the invention is carried out in any conventional manner, for example via a refrigerator, cold storage or storage effect of the goods contained therein, the use of cold storage 7 is preferred, in particular latent heat storage. A latent heat storage device is a device that can hide thermal energy, with little loss, with many repetition cycles and for a long time. For this purpose, so-called phase change materials (PCM) are used, the latent heat of fusion, solution heat or absorption heat of which is significantly greater than the heat that they can store due to their normal specific heat capacity (without the phase change effect).

Memory elements filled with paraffin are preferably used as PCM, e.g. E.g .: a PCM, which should keep the temperature in the container in the range 2 - 8 ° C and has a melting point of 4 ° C. PCM serve as a buffer against undesired cooling and heating. The latent heat stores are removably attached in the room for the goods, e.g. E.g .: in holders in the form of rails 71. The used stores can thus be exchanged with the regenerated ones.

The space for goods is preferably designed and dimensioned in such a way that international standard pallets (US, Asia, Europe) can be inserted and lashed into them.

• Höhe: 1.300 - 1.600 mm;
• Breite 800 - 2.000 mm;
• Tiefe 1.400 - 1.800 mm;
• Dicke der Sandwichkunststoffplatte (Innengehäuse) 10- 20 mm;
• Dicke der Sandwichkunststoffplatte (Außengehäuse) 10-50 mm;
• Abstand zwischen Innen. und Außengehäuse: 25 - 80 mm; und/oder
• Wärmeleitfähigkeit der Thermoisolierung: 0,002 - 0,009 W/mK

The container preferably has the following dimensions, particularly when used as an air transport container:

• Height: 1,300 - 1,600 mm;
• Width 800 - 2,000 mm;
• Depth 1,400 - 1,800 mm;
• Thickness of the sandwich plastic plate (inner casing) 10- 20 mm;
• Thickness of the sandwich plastic plate (outer housing) 10-50 mm;
• Distance between inside. and outer housing: 25 - 80 mm; and or
• Thermal conductivity of thermal insulation: 0.002 - 0.009 W / mK

These dimensions allow international standard pallets (US, Asia, Europe) to be placed in the transport container.

If the thickness of the sandwich plastic plate of the inner casing is smaller than the thickness of the sandwich plastic plate of the outer casing, weight is saved because the requirements for the stability of the outer casing are higher.

Further advantages result from the following description and the attached figures.

Fig. 1 shows a thermally insulated transport container 1 according to the invention closed with a door 5 in an embodiment as an air cargo refrigerated container. The self-supporting outer housing 1a is formed by walls 3a made of sandwich plastic plates with a honeycomb core which is welded to both sides with a cover layer, the honeycomb core and the cover layers being made of the thermoplastic material PP. The structure of the sandwich plastic panels is not shown in the figures. Adjacent sandwich plastic sheets 3a are along their common edge 32 and / or over a corner 31 fastened and sealed together by welding. The container is closed by a door 5.

Fig. 2 shows the container Fig. 1 on average through door 5 and housing 1a, 1b. The thermally insulated transport container 1 has a double-shell housing 1a, 1b to form a space 2 for goods. The self-supporting outer housing 1a consists of sandwich plastic plates 3a welded along their common edge 32 or corner 31. It contains the self-supporting inner housing 1b formed in the same way, consisting of sandwich plastic plates 3b welded along their common edge 32 or corner 31. The inner housing 1b forms the space 2 for goods and is arranged at a distance from the outer housing 1a in the outer housing. The space between the inner and outer housing is filled with thermal insulation 4, here numerous vacuum insulation panels (VIP). The vacuum insulation panels 4 are fastened in the outer housing 1a. The inner housing 1b is inserted into the vacuum insulation panels 4.

The walls 3 thus essentially consist of two layers of sandwich plastic sheets 3a, 3b with VIP thermal insulation 4 in between.

The space 2 contains numerous latent heat stores 7 as cooling stores, which are removably inserted in holders in the form of rails 71. These are standard products that can therefore be procured in numerous variants and at low cost.

Fig. 3 shows the container 1 with the door 5 opened by 270 °. The inner doors 5a consist of struts 52, which serve in part as rails for inserting the latent heat accumulator 7. As a result, they are decoupled from the heat-insulating door 5, which is therefore particularly light and only needs a weakly dimensioned joint.

Airline rails 8 on the floor of the room formed by the inner housing 1b permit secure fastening of goods placed in standard containers in room 2.

Fig. 4 shows the outer housing with vacuum panels 4 fastened therein, which are visible because the inner housing 1b is not inserted. The vacuum insulation panels 4 each have a vacuum detector on their outer wall, here in the form of a strain gauge 6 (DMS) for monitoring the air pressure in the respective vacuum insulation panel. It is not shown here that each vacuum detector comprises a digital circuit with its own address, which can be read out via a data bus and all vacuum detectors are connected to a data bus; and a readout unit is connected to the data bus in such a way that the air pressure can be called up continuously or on user request from all vacuum detectors.

Claims (7)

1. A thermally insulated transport container (1)
   with a housing (1a, 1b) for forming a space (2) for goods, with walls (3, 3a, 3b), wherein sandwich plastic plates are provided as walls (3, 3a, 3b), with a honeycomb core welded on both sides to one covering ply, respectively, the honeycomb core and the covering plies consisting of a thermoplastic material, preferably PP, characterized in that a thermal insulation (4) abuts against the walls, wherein the walls (3a or 3b) have two plies of the sandwich plastic plates with an abutting thermal insulation (4) located therebetween, wherein
   adjacent sandwich plastic plates (3a or 3b), along their joint edge (32) and/or across the corner (31), are attached to each other and preferably sealed by welding, wherein welding is carried out by means of fusion welding, heated-air welding or plastic extrusion welding, and
   the transport container (1) has a frameless construction, wherein the sandwich plastic plates (3a or 3b) that are connected to each other form a self-supporting housing (1a or 1b), wherein no further stiffening elements in addition to the sandwich plastic plates, the thermal insulation (4) and a door reinforcing means for a door (5) are provided,
2. The container according to any one of the preceding claims, characterized in that vacuum insulating panels are provided as thermal insulation (4).
3. The container according to any one of the preceding claims, characterized in that a self-supporting outer housing (1a) of welded-together sandwich plastic plates and a self-supporting inner housing (1b) of welded-together sandwich plastic plates is provided, the inner housing (1b) forming the space for goods and being disposed in the outer housing at a distance from the outer housing (1a), the space between the inner and the outer housing being filled with the thermal insulation (4),
   the insulation further preferably being fastened in the outer housing (1a) in a planar manner or in portions or in a point-shaped manner, and the inner housing (1a) further preferably being inserted into the insulation (4).
4. The container according to any one of the preceding claims, characterized in that the sandwich plastic plates consist exclusively of thermoplastic material, preferably PP.
5. The container according to any one of the preceding claims, characterized in that the one or both covering plies and/or the honeycomb core are fiber reinforced, in particular glass or carbon fiber reinforced and/or have such a covering and/or intermediate ply
   and/or
   the honeycomb core, with regard to the materials, is homogeneously connected to the cover layers by means of thermally fused connection.
6. The container according to any one of the preceding claims, characterized in that the thermal conductivity of the thermal insulation is 0.002 - 0.009 W/m K.
7. The container according to any one of the preceding claims, characterized in that the door reinforcing means comprises a profile, in particular a frame formed therefrom, consisting of a light metal alloy, in particular aluminum, which is attached to the outer housing and the inner housing and connects them with one another.

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