Stacked disc cooler, base plate for motor vehicles with a stacked disc cooler

Abstract

Stacked disc cooler (1) with a plurality of heat exchanger plates (2) arranged one above the other in a stack and a base plate (3) arranged at the end of the stack, wherein the base plate (3) has a flat plate (4) and a frame plate (5) arranged above it with a corrugated inner edge (6) which, when the stacked disc cooler (1) is mounted, is at least linearly bonded to one of the heat exchanger plates (2), characterized in that for a height h of a flank of the corrugated inner edge (6) facing the heat exchanger plate (2) the following condition applies: b < h < a, where - a = maximum height of the corrugated inner edge (6), - b = distance of the corrugated inner edge (6) from the plate (4), where 0 < b < a.

Description

The present invention relates to a stacked disc cooler with a plurality of heat exchanger plates arranged one above the other in a stack and a base plate arranged at the end of the stack according to the preamble of claim 1. The invention further relates to a base plate for such a stacked disc cooler and to a motor vehicle with such a stacked disc cooler. Stacked disc coolers, especially stacked disc oil coolers, consist of a base plate, possibly a reinforcing disc, and the individual stacked, heat-transferring heat exchanger plates with or without turbulence inserts. A cover plate and corresponding connections, particularly oil and coolant connections, are also provided. A critical point for the pressure cycling resistance of the stacked disc cooler is the connection of the block or reinforcing disc to the base plate. Due to the pressure cycling and the bolting at the edge of the base plate, the base plate undergoes a so-called "breathing" or "deformation," which can lead to stresses in the connection between the block or reinforcing disc and the base plate. These stresses can be reduced by using rigid / flexurally resistant base plates, but this requires a comparatively large amount of material, i.e., thick sheets.Materials with high strength, and therefore expensive materials, can be achieved. From WO 2007 / 038 871 A1, a stacked disc cooler of the generic type is known, comprising a plurality of heat exchanger plates arranged one on top of the other in a stack and a base plate arranged at the end of the stack, which has a flat plate and a frame plate arranged above it with a corrugated inner edge, which, when the stacked disc cooler is mounted, is at least linearly bonded to one of the heat exchanger plates. From DE 10 2010 001 828 A1, a stacked disc cooler is known, comprising a stack of heat exchanger plates supported by a first base plate. In addition to the first flat base plate, a second base plate is provided with a recess surrounded by a frame-like support rim that rests on the first base plate, and the stack extends into the recess up to the supporting frame-side contact. This is intended to achieve a reduced overall height while saving material and maintaining or even increasing strength. From DE 10 2009 030 095 A1, another stacked disc cooler, in particular a stacked disc oil cooler, is known, which has a plurality of heat exchanger plates arranged one on top of the other in a stack and a base plate arranged at one end of the stack. The base plate has an edge directed towards the stack, which at least partially follows the outline of the stack. This is intended to enable the production of a dimensionally rigid and at the same time cost-effective base plate. As mentioned at the beginning, with stacked disc coolers known from the prior art, the desired high rigidity in the area of ​​the base plate can only be achieved through expensive and thick materials, which not only have a high weight, but also require a comparatively high energy input for soldering. The present invention therefore deals with the problem of providing an improved embodiment for a stacked disc cooler of the generic type, which is in particular lighter and more cost-effective. This problem is solved according to the invention by the subject matter of independent claim 1. Advantageous embodiments are the subject matter of the dependent claims. The present invention is based on the general concept of constructing a stacked disc cooler, particularly a stacked disc oil cooler, with a plurality of heat exchanger plates arranged one above the other in a stack and a base plate arranged at the end of the stack, the latter consisting of two parts: a flat plate and a frame plate arranged above it with a corrugated inner edge. When the stacked disc cooler is mounted, this inner edge is at least linearly bonded to a heat exchanger plate and supports it at its edge. The corrugated inner edge allows for significant stiffening of the frame plate and, consequently, also of the flat plate or the base plate, without requiring the previously necessary high material costs and thus also the expense and weight of the components.The frame plate with its corrugated inner edge can be manufactured relatively cost-effectively as a stamped sheet metal part. Even the folding or unfolding of the corrugated inner edge is technically simple, for example, through a suitable upsetting or bending process. The corrugated inner edge stiffens the frame plate and, consequently, the entire base plate, to such an extent that the previously required material thickness can be dispensed with. This allows not only the base plate but also the entire stacked disc cooler to be constructed much more easily, which is particularly advantageous in terms of fuel consumption when used in modern vehicles. Furthermore, less energy is required when brazing the frame plate to the base plate due to the reduced material thickness, thus making the production of the base plate more environmentally friendly. The plate advantageously has a thickness d1 of approximately 1 mm to 6 mm. Previously, the base plate was made of solid material and had a thickness of approximately 4 mm to 12 mm, and was therefore, in the worst case, 12 times heavier than the plate according to the invention, resulting in high material costs and considerable weight. In a further advantageous embodiment of the solution according to the invention, the frame plate has a thickness d2 of approximately 1 mm to 4 mm. Compared to previous reinforcing discs, the frame plate according to the invention is also significantly thinner, since the required stiffness is no longer achieved through the material thickness, but rather through the corrugated inner edge. The inner edge can be formed completely around the entire plate or only around a portion of the subsequent heat exchanger plate. Advantageously, the flank angle α of the corrugated inner edge corresponds to a flange angle β of the heat exchanger plate, so that the corrugated inner edge can be bonded to the heat exchanger plate over a flat surface when the stacked disc cooler is mounted. In this specific case, a flat brazing joint can thus be achieved between the corrugated inner edge and the flange, i.e., the raised edge of the heat exchanger plate, resulting in a particularly tight connection. The flat brazing also allows for better absorption of pressure pulsations. According to the invention, the following condition applies to the height h of the flank of the corrugated inner edge facing the heat exchanger plate: b < h < a, where a represents the maximum height of the corrugated inner edge and b describes the distance of the corrugated inner edge from the plate. The distance b lies between the maximum height a of the corrugated inner edge and greater than zero. The condition described above already suggests the wide variety of embodiments possible for the stacked disc cooler according to the invention, such that all embodiments are possible, from soldering the flank over the entire height to merely a linear solder joint. In a further advantageous embodiment of the solution according to the invention, the plate and / or the frame plate are designed as stamped sheet metal parts. This enables cost-effective and technically simple, yet precise, production of the base plate, wherein, for joining the plate to the frame plate, at least one of the two plates is solder-clad or has a correspondingly applied solder foil. This makes soldering in a suitable soldering furnace comparatively easy. Further important features and advantages of the invention will become apparent from the dependent claims, the drawings and the associated description of the figures based on the drawings. It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention. Preferred embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein identical reference numerals refer to identical or similar or functionally identical components. Figure 1 shows, schematically, a base plate not designed according to the invention in an exploded view, Figure 2 shows a sectional view through a stacked disk cooler not designed according to the invention, Figure 3 shows a detailed view of detail A from Figure 2 in a modified embodiment, Figure 4 shows the detailed view A from Figure 2, and Figure 5 shows a view as in Figure 3, but with an embodiment of the inner edge according to the invention. As shown in Figures 2, 3, 4 to 5, a stacked disc cooler 1, for example a stacked disc oil cooler for a motor vehicle, has a plurality of heat exchanger plates 2 arranged one above the other in a stack and a base plate 3 arranged at the end of the stack. Not shown is a cover plate arranged on top of the stack with corresponding connections for coolant or oil. According to the invention, the base plate 3 is constructed in two parts, namely a flat plate 4 and a frame plate 5 arranged above it with a corrugated inner edge 6.The raised and corrugated inner edge 6 allows for significantly improved stiffening of the frame plate 5 and, consequently, of the entire base plate 3, so that the base plate 3 according to the invention can be made significantly thinner, i.e., with significantly less material and therefore also significantly lighter, compared to base plates known from the prior art. According to the invention, the plate 4 has a thickness d1 of only 1 to 6 mm, which represents a significant reduction compared to plates known from the prior art with a thickness of up to 12 mm. The frame plate 5, according to the invention, has a thickness d2 between approximately 1 mm and 4 mm and is therefore also significantly thinner and thus considerably lighter than comparable reinforcing discs known from the prior art. Overall, the stacked disc cooler 1 according to the invention can thus use a base plate 3 that is reduced in thickness and weight, but has comparable or even better stiffness than solid base plates known from the prior art.Due to the reduced use of material, significantly less energy is required when soldering the frame plate 5 to the plate 4 of the base plate 3, which has a positive effect on the environmental footprint. In general, it is possible to manufacture the frame plate 5 as a cost-effective stamped sheet metal part and to either simply emboss or stamp the corrugated inner edge 6, as shown, for example, in Fig. 3, or to form it accordingly, as shown in Figs. 2, 4, and 5. For soldering together, the frame plate 5 and / or the plate 4 are provided with a solder plating or a corresponding solder foil. Looking at Fig. 3, it can be seen that the corrugated inner edge 6 is connected linearly to a flange 7, that is, to an edge of the heat exchanger plate 2, and is thus only soldered to it linearly. In contrast, in the embodiments of the corrugated inner edge 6 shown in Figs. 2 and 4, a flank angle α of the corrugated inner edge 6 is selected such that it corresponds to a flange angle β of the heat exchanger plate 2, that is, to a flange 7 of the heat exchanger plate 2, and thus the corrugated inner edge 6 is connected over a surface area to the flange 7 of the heat exchanger plate 2 when the stacked disc cooler 1 is mounted, in particular by soldering. This allows the pressure pulsations occurring in this area to be absorbed particularly well or introduced into the base plate 3. In contrast, if one considers Fig. 5, it can be seen that the following condition applies to the height h of the flank of the corrugated inner edge 6 facing the heat exchanger plate 2: where a represents the maximum height of the corrugated inner edge 6 and b denotes the distance of the corrugated inner edge 6 from the plate 4, with b being between 0 and a. Generally, the corrugated inner edge 6 is designed such that it completely surrounds the heat exchanger plates 2, although it is also conceivable that it is only partially arranged on the inner edge of the plate 4. In general, the corrugated inner edge 6 according to the invention allows the critical point for pressure cycling to be shifted from the brazed joint of the heat exchanger plate 2 to the base plate 3 to a stiffer and stronger location, which leads to an overall increase in strength.Another function of the corrugated inner edge 6 is to increase the wall thickness in the area of ​​the rim 7 of the lowest heat exchanger plate 2, which eliminates the need for the reinforcing disc previously required in this area, as this function is now performed by the frame plate 5 or its corrugated inner edge 6. With the base plate 3 according to the invention, and in particular also with the stacked disc cooler 1 according to the invention, the required installation height of the stacked disc cooler 1 can be reduced, while maintaining the same power-to-pressure-loss ratio. The elimination of the previously required reinforcing discs also eliminates the need for the manufacturing tooling previously required for them, thus reducing the overall manufacturing effort. Furthermore, a reduction in weight and material usage can be achieved, enabling the base plate 3 according to the invention, and consequently the stacked disc cooler 1 according to the invention, to be manufactured cost-effectively and in an environmentally friendly manner.

Claims

Stacked disc cooler (1) with a plurality of heat exchanger plates (2) arranged one above the other in a stack and a base plate (3) arranged at the end of the stack, wherein the base plate (3) has a flat plate (4) and a frame plate (5) arranged above it with a corrugated inner edge (6) which, when the stacked disc cooler (1) is mounted, is at least linearly bonded to one of the heat exchanger plates (2), characterized in that for a height h of a flank of the corrugated inner edge (6) facing the heat exchanger plate (2) the following condition applies: b < h < a, where - a = maximum height of the corrugated inner edge (6), - b = distance of the corrugated inner edge (6) from the plate (4), where 0 < b < a. Stacked disc cooler according to claim 1, characterized in that the plate (4) has a thickness d1 of approximately 1 mm to 6 mm. Stacked disc cooler according to claim 1 or 2, characterized in that the frame plate (5) has a thickness d2 of approximately 1 mm to 4 mm. Stacked disc cooler according to one of claims 1 to 3, characterized in that a flank angle α of the corrugated inner edge (6) corresponds to a flange angle β of a flange (7) of the heat exchanger plate (2), so that the corrugated inner edge (6) is connected to the heat exchanger plate (2) over a surface when the stacked disc cooler (1) is mounted. Stacked disc cooler according to one of claims 1 to 4, characterized in that the plate (4) and / or the frame plate (5) are designed as a stamped sheet metal part. Stacked disc cooler according to one of claims 1 to 5, characterized in that the plate (4) and / or the frame plate (5) are solder-plated. Base plate (3) for a stacked disc cooler (1) according to one of the preceding claims, characterized in that the base plate (3) has a flat plate (4) and a frame plate (5) arranged above it with a corrugated inner edge (6), that for a height h of a flank of the corrugated inner edge (6) facing the heat exchanger plate (2) the following condition applies: b < h < a, where a = maximum height of the corrugated inner edge (6), b = distance of the corrugated inner edge (6) from the plate (4), where 0 < b < a. Motor vehicle with a stacked disc radiator (1) according to one of claims 1 to 6.

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