Heat exchanger, especially for vehicles
A heat exchanger including a collecting tank and at least one flat tube row. The flat tubes have a discharge end secured to the collecting tank, a closed end, and a longitudinal separator dividing the tubes into oppositely-traversed channels, wherein at least a portion of one tube wall at the closed end and the separator associated with the tube wall portion are omitted. A closure piece closes the tubes where the tube wall portions are omitted. A partition in the collecting tank separates the inlet and outlet sides. Heat exchanger elements between the flat tubes are adapted to be traversed by a medium flowing outside the tubes. The first tube row may be connected with one end to one side of the collecting tank with a second tube row connected with its first end to another side of collecting tank.
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENTNot applicable.
REFERENCE TO A MICROFICHE APPENDIXNot applicable.
TECHNICAL FIELDThe present invention is directed toward heat exchangers, and more particularly to vehicle coolant radiators.
BACKGROUND OF THE INVENTION AND TECHNICAL PROBLEMS POSED BY THE PRIOR ARTA radiator for the cooling unit of an internal combustion engine of a vehicle is shown and described in DE 34 40 489 C2, and has a collecting tank divided into parts by a partition, with a series of flat tubes discharging on one end into the tank. The flat tubes are divided into oppositely traversed channels by a longitudinal separator, which terminates short of the other tube end, whereby there is flow connection between the channels in the other end of the flat tubes. Accordingly, it will be appreciated that flowing medium in one part of the collecting tank enters one channel on the tube one end, flows through that channel to the other end, then passes to the adjacent channel at that other end (where there is no channel separator), and then flows back in the opposite direction through the adjacent channel to the other part of the collecting tank. The longitudinal separator is formed as an inserted rod or as a bead in the wall of the flat tube, which was flattened a bit on the other end of the flat tube. Both the rod to be inserted and the part of the bead to be flattened are obstacles to a cost-effective manufacturing process.
The present invention is directed toward overcoming one or more of the problems set forth above.
SUMMARY OF THE INVENTIONAccording to one aspect of the present invention, a heat exchanger includes at least one collecting tank and at least one row of flat tubes. The flat tubes have a first end secured to the collecting tank to discharge therein, a closed second end, and at least one longitudinal separator in the tubes dividing the tubes into oppositely-traversed channels, wherein at least a portion of one tube wall at the closed second end and the separator associated with the tube wall portion are omitted. At least one closure piece closes the tubes where the portions of the one tube wall are omitted, and at least one partition in the collecting tank separates the inlet side from the outlet side. Heat exchanger elements are arranged between the flat tubes and adapted to be traversed by a medium flowing outside of the flat tubes.
In one form of this aspect of the present invention, the heat exchanger is a vehicle coolant radiator.
In another form of this aspect of the present invention, a common closure piece is provided for the second ends of a plurality of the tubes.
In still another form of this aspect of the present invention, separate closure pieces are provided for each tube having a wall portion omitted.
In yet another form of this aspect of the present invention, aligned portions of both side walls of each flat tube are omitted.
According to another aspect of the present invention, a heat exchanger includes at least one collecting tank and at least two rows of flat tubes. The flat tubes have a first end secured to the collecting tank to discharge therein, a closed second end, and at least one longitudinal separator in the tubes dividing the tubes into oppositely-traversed channels. A first row of flat tubes is connected with one end to one side of the collecting tank and a second row of flat tubes is connected with its first end to another side of collecting tank. A partition in the collecting tank separates the inlet side from the outlet side; and heat exchanger elements are arranged between the flat tubes and adapted to be traversed by a medium flowing outside of the flat tubes.
In one form of this aspect of the present invention, at least a portion of one tube wall at the closed second end and the separator associated with said tube wall portion are omitted, and at least one closure piece closes the tubes where the portions of the one tube wall are omitted.
In another form of this aspect of the present invention, the heat exchanger is a vehicle coolant radiator.
In still another form of this aspect of the present invention, the first and second rows of flat tubes lie in a common plane.
In yet another form of this aspect of the present invention, the first and second rows of flat tubes are at an angle to each other.
In another form of this aspect of the present invention, the flat tubes have different tube lengths (L).
In still another form of this aspect of the present invention, the tube lengths (L) are different in both rows.
In yet another form of this aspect of the present invention, the tube lengths (L) are the same in both rows.
In another form of this aspect of the present invention, flow through the flat tubes occurs in the opposite direction in all rows of flat tubes.
BRIEF DESCRIPTION OF THE DRAWINGS
The Figures illustrate different variants of air-cooled coolant radiators which may be advantageously produced completely from aluminum. The coolant, according to the arrows C (see, e.g.,
The heat exchanger according to
It should be appreciated that it would be within the scope of the present invention for there to be, for example, two directly adjacent or connected collecting tanks (with, e.g., an inlet tank and an outlet tank). Further, it would be within the scope of the invention, depending upon the requirements of a particular application, to include more than one partition in the collecting tank(s).
A single row of flat tubes 10 with corrugated ribs 12 is shown in
The flat tubes 10 can, for example, be advantageously produced from an endless sheet of metal which is shaped and soldered or welded, where the longitudinal separator 46 is formed by the longitudinal edges of the sheet metal, where the longitudinal edges are in contact roughly in the center of the flat tube and there form the longitudinal separator 46. It should be appreciated, however that advantages of the present invention could be obtained with a variety manufacturing methods used to form the basic tubes, including manufacturing of flat tubes in which several channels per flow direction and several longitudinal separators are provided.
Advantageous formation of the other tube ends 54 (remote from the collecting tank 20) is shown in
Manufacture of tubes 10 according to this aspect of the invention can be advantageously accomplished by first forming tubes stock, either continuously or at desired lengths, then cutting tubes from the tube stock to the desired length, including forming cut-outs 60 at one end 54 such as described herein, then adding the closure piece(s) 70 while assembling the tubes 10 with the collecting tank 20.
The advantageous cut-out 60 according to the present invention may be formed in a variety of ways and configurations.
The cut-out 60 in the embodiment illustrated in
In the embodiment shown in
Other embodiments are shown in
Two heat exchangers are shown in
Moreover,
The difference between
Moreover, it should be appreciated that while the formation of the tubes by use of cut-outs 60 such as previously described could be advantageously used with heat exchangers such as shown in
It should also be appreciated that these are only practical examples intended to illustrate that different forms of the heat exchanger are possible by the simple expedient of providing different tube lengths L, and variants having a heat exchanger shape that differs significantly from
It should further be appreciated that the tubes requiring passage between the channels 50, 52 at the outer end 54 may be relatively simply and efficiently produced by use of cut-outs 60 as described. For example, production of cut-outs is simpler than flattening of the bead such as was done in the prior art. This is especially true when the flat tubes are extremely flat (free width 1 mm or less), as often used, for example, with vehicle engine radiators. Moreover, production of the cut-outs 60 can be readily and efficiently accomplished simultaneously with cutting off lengths of the endlessly produced flat tubes.
Moreover, it should be appreciated that heat exchangers according to the invention promises excellent heat exchange efficiency, because heat exchange according to the cross-counterflow principle is provided. That is, the coolant flows in a channel 50 within the flat tubes 10 and flows back in a parallel channel 52 of the flat tube 10 in counter-current, and cooling air flows across the flat tubes 10 between them and through the heat exchange elements (corrugated ribs) 12.
Still other aspects, objects, and advantages of the present invention can be obtained from a study of the specification, the drawings, and the appended claims. It should be understood, however, that the present invention could be used in alternate forms where less than all of the objects and advantages of the present invention and preferred embodiment as described above would be obtained.
Claims
1. A heat exchanger, comprising:
- at least one collecting tank;
- at least one row of flat tubes having a first end secured to said collecting tank to discharge therein, a closed second end, and at least one longitudinal separator in said tubes dividing said tubes into oppositely-traversed channels, wherein at least a portion of one tube wall at said closed second end and the separator associated with said tube wall portion are omitted;
- at least one closure piece closing said tubes where said portions of said one tube wall are omitted;
- at least one partition in said collecting tank separating the inlet side from the outlet side; and
- heat exchanger elements arranged between said flat tubes and adapted to be traversed by a medium flowing outside of said flat tubes.
2. The heat exchanger of claim 1, wherein said heat exchanger is a vehicle coolant radiator.
3. The heat exchanger of claim 1, wherein a common closure piece is provided for said second ends of a plurality of said tubes.
4. The heat exchanger of claim 1, wherein separate closure pieces are provided for each tube having a wall portion omitted.
5. The heat exchanger of claim 1, wherein aligned portions of both side walls of each flat tube are omitted.
6. A heat exchanger, comprising:
- at least one collecting tank;
- at least two rows of flat tubes having a first end secured to said collecting tank to discharge therein, a closed second end, and at least one longitudinal separator in said tubes dividing said tubes into oppositely-traversed channels, wherein a first row of flat tubes is connected with one end to one side of the collecting tank and a second row of flat tubes is connected with its first end to another side of collecting tank;
- at least one partition in said collecting tank separating the inlet side from the outlet side; and
- heat exchanger elements arranged between said flat tubes and adapted to be traversed by a medium flowing outside of said flat tubes.
7. The heat exchanger of claim 6, wherein at least a portion of one tube wall at said closed second end and the separator associated with said tube wall portion are omitted, and further comprising at least one closure piece closing said tubes where said portions of said one tube wall are omitted.
8. The heat exchanger of claim 6, wherein said heat exchanger is a vehicle coolant radiator.
9. The heat exchanger of claim 6, wherein said first and second rows of flat tubes lie in a common plane.
10. The heat exchanger of claim 6, wherein said first and second rows of flat tubes are at an angle to each other.
11. The heat exchanger of claim 6, wherein said flat tubes have different tube lengths (L).
12. The heat exchanger of claim 6, wherein said tube lengths (L) are different in both rows.
13. The heat exchanger of claim 6, wherein said tube lengths (L) are the same in both rows.
14. The heat exchanger of claim 6, wherein flow through the flat tubes occurs in the opposite direction in all rows of flat tubes.
Type: Application
Filed: Dec 5, 2005
Publication Date: Jun 22, 2006
Inventor: Jens Nies (Holzgerlingen)
Application Number: 11/294,309
International Classification: F28D 7/06 (20060101);