A cooling element, which consists of at least two layers of vapour-transmitting foil material with a water-repellent coating. norcold rv refrigerator The cooling element has an inner compartment (5) and an outer compartment (6). The inner compartment (5) is connected to the outer compartment (6) by means of fusion seams (4). The fusion seams 4 are in line with the welded connection 7. This construction ensures that the inner compartment (5) and the outer compartment (6) of the cooling element remain closed together, so that the cooling effect is enhanced.
The inner compartment (5) of the cooling element may be defined by means of an intermediate layer (3) that is inserted between the two layers of foil material 1 and 2. In this case, the welded connections 4 and 7 are rounded at some of their corners and ends so as to prevent stress concentrations from arising when the cooling element is bent. This construction is especially suitable for a rucksack.
In some embodiments, a buffer reservoir (8) is formed adjacent to the compartment (5) between the two layers of foil material and is separated from this by a welded seam (4). This buffer reservoir (8) has a maximal volume that is essentially equal to the liquid volume of the liquid absorbing, vapour-releasing material when this material is saturated with liquid.
Furthermore, a flow restriction (9) is provided in the form of at least one liquid passage between the compartment and the buffer reservoir (8). This enables the fluidization of the liquid absorbing, vapour-releasing materials and the buffer reservoir thereby ensuring that the cooling function is maintained during an essentially longer period of time than that in which the liquid absorbing, vapour-releasing medium would be saturated with liquid.
The buffer reservoir (8) is preferably made of thermoplastic plastic, for example, polyethylene terephthalate or polypropylene. This plastic has a very high moisture-vapour transmittance and is therefore highly resistant to abrasion, such as that which occurs in the case of welding. This is advantageous for the welding operation and, in turn, for the entire production process, as it means that the cooling element can be ready substantially immediately after the welding.
Moreover, in some embodiments the welded connection 4 and 7 are rounded at some of its corners and ends so as to prevent stress concentrations and tears from arising when the cooling element is bent. The welded connection 4 and 7 of this construction is also particularly mechanically reliable, leak-proof, and can be finished substantially immediately after the welding operation.
Further welded connections (7) are provided between said layers of foil material within the circumference of the compartment (5). These welded connections make the foil materials better together than they would be if only the edges necessary for forming a compartment were welded, which in turn makes the overall assembly stronger and less vulnerable.
Thermoelectric coolers are a type of solid-state heat pump that utilize the Peltier effect. They are commonly used in scientific devices, for instance, to perform PCR and other molecular biology techniques, which involve rapid heating and cooling of the reaction mixture. Besides the use in laboratory equipment, these components are widely used as solid-state heat pumps for transporting temperature-sensitive products and components.