An exemplary embodiment of the invention is illustrated in the drawing and is described in more detail below. In the drawing:
FIG. 1 shows a header/collecting tube unit,
FIG. 2 shows the unit according to FIG. 1 in an exploded illustration, and
FIG. 3 shows a section through the header with dryer and filter.
FIG. 1 shows a header 1, consisting of a tubular portion 2 and of an extruded portion 3, and a collecting tube 4 with rim holes 5 for flat tubes, not illustrated, of a refrigerant condenser. The header 1 and collecting tube 4 form an integrated unit of a condenser module initially mentioned.
FIG. 2 shows the unit according to FIG. 1 in two illustrations: the upper part shows the unit according to FIG. 1 in the assembled state; and the lower part shows the header 1 and the collecting tube 4 as separate components, that is to say before their assembly. The tubular portion 2 is inserted into the extruded portion 3 and is soldered to the latter. The extruded portion 3 has two overflow orifices 5 which are assigned two rim holes 6 on the collecting tube 4. The more particular construction and assembly of the header 1 and of the collecting tube 4 are described in more detail in the Applicant's older patent application bearing the file number 101 54 891.
FIG. 3 shows the design according to the invention of a header 10 which corresponds in its type of construction to the header 1 in conjunction with the collecting tube 4 according to FIGS. 1 and 2. The header 10 is composed of a tubular piece 11 of smaller wall thickness and an extruded tubular piece 12 of larger wall thickness. The lower tubular piece 12 has an upper overflow orifice 13, that is to say an inflow orifice, and a lower overflow orifice 14, that is to say an outflow orifice. The upper tubular piece 11 is inserted into the lower tubular piece 12 and is connected to the latter in the region of the joining point 15 by soldering. The two tubular pieces 11 and 12 are closed off in a pressuretight manner, likewise by soldering, at their ends located opposite one another, in each case by means of closing covers 16, 17. The tubular piece 11, which is produced from a welded tube, has a portion 18 of widened cross section which has adjoining it on both sides portions 19 and 20 with an equal smaller cross section. Such a cross-sectional widening can be produced by the expansion of the tube 11, for example by internal high pressure forming (IHF) or what is known as hydroforming. This cross-sectional widening in the region of the portion 18 results in steps 21 and 22 in the profile of the tube 11. In the region of these steps 21, 22 perforated disks 23 and 24, that is to say disks with passage orifices 25 and 26 which are distributed in a multiplicity over the entire cross section, are inserted into the interior of the tubular portion 18. Above the lower perforated disk 23 is arranged a felt layer 27, above which a dryer medium in the form of granulate 28 is located in a dense packing. This dryer granulate 28 is resistant to high temperature, that is to say it does not undergo any impairment during the soldering process. Above the uppermost layer of the granulate 28 is arranged a pressure plate 29 which is supported on the lower surface of the perforated plate 24 via a compression spring 30. This ensures that the packing of the granulate 28 is compressed and does not slip out of place and therefore no abrasion occurs.
The two perforated disks 23, 24 are supported, on the one hand, with their edges, in the region of the transitions 21, 22, positively and frictionally with respect to the wall of the tubular piece 11. In addition, during the final soldering process, they are soldered to the tubular piece 11, so that they form an unreleasable connection with the tube 11. Alternatively, adhesive bonding of the perforated plates 23, 24 to the tubular piece 11 may also be provided. In the lower region of the header 10, that is to say in the extruded tubular piece 12 and between the two overflow orifices 13, 14, is arranged a filter sieve 31 which is of cup-shaped design and has a bottom 32 and an annular edge region 33. The latter is inserted in an annular groove 34 in the tubular piece 12 and is anchored there. Premounting before soldering is therefore carried out by insertion of the edge 33 into the groove 34, and final firm materially integral connection takes place during the concluding process of soldering the condenser.
According to a variant, not illustrated, the filter sieve may also be of annular design.
The functions of drying, on the one hand, and of filtration, on the other hand, are separated spatially here, that is to say drying takes place in the upper region of the header 10, whereas filtration takes place in the lower region. As is known from the prior art initially mentioned, the refrigerant passes through the inflow orifice 13, following the arrow E, into the interior of the header 10, flows through the filter sieve 31 of cup-like design and leaves the header via the outflow orifice 14, following the arrow A. This results in a relatively minor pressure drop for the refrigerant which flows through the header 10, since the refrigerant does not have to flow through the dryer, as it does in the prior art. Drying takes place in that refrigerant vapor and/or refrigerant liquid which pass into the upper region of the header 10 come into contact with the dryer granulate 28 there and are thus dehumidified. In the upper region of the header 10, that is to say above the inflow orifice 13, therefore, a secondary flow of the refrigerant is formed, which leads first to the dryer granulate 28 and from there, dehumidified, flows back in the direction of the filter sieve 31. The two functions of drying and of filtration are consequently ensured.
As already mentioned above, the invention can also be implemented with other forms of header construction, for example in the case of a continuous extruded header profile.
Patent Application
20080047297
