Patent Application
20070023170
The present invention relates to a tube/plate condenser for a cooling circuit of a refrigerator and/or freezer comprising a tube preferably bent in a meandering shape in which the cooling circuit medium can be condensed and a carrier panel made of sheet metal to which the tube is secured.
A tube/plate condenser of this type for refrigerators and/or freezers is known, for example, from DE 20 2004 017 652 U1. Rear wall condensers of this type typically consist of a steel panel onto which the steel tube bent in a meandering shape is mounted and secured, with both the steel panel and the steel tube being lacquered as a rule. Since the heat dissipation is limited with condensers of this type, the tube bent in a meandering shape must have a correspondingly large length and the carrier panel of sheet metal serving the heat dissipation to ambient must have a correspondingly large surface so that the refrigerant evaporated in the evaporator of the refrigeration circuit is sufficiently cooled when flowing through the tube and is thus condensed again. The named DE 20 2004 017 652 U1 proposes, for the improvement of the heat dissipation, providing the condenser tube moving to and fro in a meandering manner with a specific bending radius and thus giving the straight sections a predetermined spacing since a more uniform heat radiation should hereby be achieved over the surface of the carrier panel. The heat dissipation nevertheless remains limited and the required carrier panel surface and tube length thus remains considerable.
Starting from this, it is the object underlying the invention to provide an improved condenser of this named type which avoids disadvantages of the prior art and further develops the latter in an advantageous manner. A further improved heat dissipation and/or a smaller construction size of the condenser should in particular be achieved.
This object is solved in accordance with the invention by a condenser herein. Preferred aspects of the invention are also the subject of the invention herein.
The present invention is based on the consideration that the heat dissipation of the evaporator can be effectively improved by an increase of the thermal conductivity of the carrier panel, on the one hand, and by an increase of the heat transfer from the condenser tube to the sheet metal of the carrier panel, on the other hand, with both being able to be achieved in a particular degree by a specific material pairing between the material of the carrier panel and the material of the tube. In accordance with the invention, the carrier panel consists of an aluminum sheet, whereas the tube is a steel tube or an aluminum tube. A considerably improved heat dissipation of the condenser can hereby be achieved over the previously typically used steel tubes on sheet steel carrier panels. On the one hand, the aluminum sheet has a much better thermal conductivity over the previously customary steel sheets. On the other hand, a very good heat transfer from the tubes to the carrier panel can be achieved by the material pairing selected. The required tube length and the correspondingly required carrier panel area can hereby be considerably reduced overall so that the condenser has a smaller construction overall. In addition, its weight can be considerably reduced.
The tube can in particular be connected to the carrier panel in a shape matched manner and/or in a force transmitting manner. In accordance with an advantageous embodiment of the invention, the carrier panel can have bent tube reception passages into which the tube is inserted such that the aluminum sheet snugly fits around the tube areally. On the one hand, a very good heat transfer between the tube and the aluminum sheet is hereby achieved. On the other hand, time-consuming joining steps such as aluminum welding or soldering can be avoided, whereby the condenser can be produced more cost favorably.
The tube reception passages advantageously fit snugly around the tube by more than 180° in cross-section such that the heat transfer area, and so the heat dissipation, is particularly large. In addition, a firm connection between the sheet metal and the tube is hereby ensured. A press fit or clamp fit is advantageously provided between the tube reception passages and the tube.
The tube can in this process generally be differently received in the tube reception passages. In accordance with an advantageous embodiment of the invention, the tube can be rolled into the aluminum sheet in the region of the tube reception passages. In this process, the carrier panel can generally be made of one single sheet of metal, with it alternatively being possible, however, to assemble the carrier panel from a plurality of sheet metal parts.
The carrier panel can in particular consist of a plurality of strips of sheet metal overlapping one another when the tube is not rolled into the aluminum sheet, but is rather received between overlapping strips of sheet metal of the carrier panel. A complete surrounding of the tube by the material of the carrier panel can hereby be achieved.
If a steel tube is used as the condenser tube, this can generally be a bare steel tube without a surface coating or surface treatment. Alternatively, a particularly favorable material pairing also results when galvanized steel tubing is used. The same applies to tinned steel tubing. A particularly favorable heat transfer can also hereby be achieved.
In contrast to the prior art, the carrier panel made of aluminum sheet and/or the condenser tube can remain unlacquered in accordance with an embodiment of the invention. Optionally, however, a lacquer coating can alternatively be provided.
The invention will be explained in more detail in the following with reference to a preferred embodiment and to associated drawings. There are shown in the drawings:
The condenser 1 shown in
The carrier panel 2 is made of a metal sheet of aluminum or of an aluminum alloy. The tube 3 can likewise consist of aluminum or of an aluminum alloy in accordance with an embodiment of the invention. Alternatively, a steel tube, which can be galvanized in accordance with one embodiment of the invention or tinned in accordance with another alternative embodiment of the invention, can be used as the condenser tube 3.
As
In the embodiment in accordance with
In the embodiment in accordance with
| Number | Date | Country | Kind |
|---|---|---|---|
| UM 202005011535.5 | Jul 2005 | DE | national |
| UM 202005012048.0 | Aug 2005 | DE | national |
