EP1775540B1 - Header for a heat exchanger - Google Patents

Description

The invention relates to a manifold for a heat exchanger according to the preamble of claim 1 and a heat exchanger with manifold.

Figure 18 of the document US 2002/0057941 A1 discloses such a manifold.

Known heat exchangers consist of collecting and distribution tanks and a block with pipes whose pipe ends open into the collection. The collecting container, which are integrally or in several parts, are formed with so-called passages, d. H. provided approximately collar-shaped openings, in which the pipe ends are inserted and connected to the collecting containers. When using thin sheets for the collection container, as is known for heat exchangers of motor vehicles, the passages are produced by chipless forming, d. H. by punching, embossing or slitting. In two-part Samrnelbehältern, which consist of a lid and a bottom, the passages can be made by means of die and stamp, for example by punching, resulting in precisely shaped passages.

By the DE 41 30 517 A1 the applicant has a two-piece junction box (sump) for a heat exchanger is known in which the passages are first formed in a flat bottom, which is then deformed U-shaped and sealed with a lid.

By the DE 41 29 573 C2 The applicant has been known a floor with passages for a terminal box (collection container), in which the passages are "torn" by means of a punch. The material of the floor is thereby torn or slotted by a cutting edge of the punch and then deformed into a passage. This produces at the end of the passage demolition edges, which have no sharp contour, but are well soldered to the recorded by the passages flat tubes.

When using one-piece headers, z. B. with circular cross-section must be used for the production of passages shared dies, which are removable according to the shapes of the passages from the closed pipe cross-section. This increases the production costs.

In the DE 195 32 860.A1 The Applicant was therefore proposed to fill a circular cylindrical manifold with a hydraulic fluid and put under pressure. To produce the passages, sharp-edged cutting punches are introduced into the pipe wall against the hydraulic internal pressure. This can be dispensed with a conventionally divided die - but the known method is costly.

By the EP 0 198 581 B1 a heat exchanger with one-piece circular cylindrical manifold with passages for receiving flat tubes was known, wherein between the passages spherical tube sections are provided. This should increase the strength of the manifold against internal pressure. A disadvantage of the known manifold is that the distance between the pipes, ie the pipe pitch is relatively large due to the spherical sections. This limits the performance of such a heat exchanger.

It is an object of the present invention to provide a manifold of the type mentioned with simple and inexpensive to produce passages, with low pipe pitches are possible.

The object of the invention is solved by the features of claim 1. Advantageous embodiments of the invention will become apparent from the dependent claims.

According to the invention, the areas between adjacent passages are flattened in the circumferential direction, i. H. the cross section of the originally circular collecting tube has in this area a flattening, which is approximately in the middle - seen in the longitudinal direction of the tube - between adjacent passages. The length of these flattened areas, seen in the circumferential direction, corresponds approximately to the length of the passages. All flattened areas affect a fictitious plane, which is a flattening of the circular cylindrical manifold, The inventive geometry of the passages or provided with passages manifold the advantage of a simple and inexpensive production is achieved, with a narrow pipe pitch can be achieved. The molding of the passages by means of radially guided to the manifold punch, which can be dispensed with entirely on a die or a hydraulic back pressure.

Preferably, the passages are made with a multi-stage tool, a punch with a cutting edge, wherein the first pipe material is slotted or torn and then shaped and calibrated, so that the geometry of the invention results in flattening of the cylinder circumference. The manifold according to the invention is dimensionally stable and inert pressure.

According to a preferred embodiment, the passage at its end facing the tube inside a circumferential contact surface, which corresponds to the circumference of the flat tubes to be used. The height of this contact surface (seen in the radial direction), corresponds to the wall thickness of the manifold. This results in the advantage of a close system between passage and flat tube and thus a firm and tight solderability.

The manifold according to the invention is advantageously used for a refrigerant condenser of an automotive air conditioning system or for a coolant radiator of a cooling circuit for a motor vehicle.

Fig. 1

eine Ansicht von unten auf einen Teil eines Sammelrohres mit Durchzügen,

Fig. 2

eine Seitenansicht des Sammelrohres gemäß Fig. 1,

Fig. 3

einen Schnitt durch das Sammelrohr in der Ebene III-III in Fig. 1,

Fig. 4

einen Schnitt in der Ebene IV-IV gemäß Fig. 1,

Fig. 5

einen Schnitt in der Ebene V-V gemäß Fig. 4 und

Fig. 6

eine Einzelheit X gemäß Fig. 1.

An embodiment of the invention is illustrated in the drawing and will be described in more detail below. Show it

Fig. 1

a view from below of a part of a manifold with passages,

Fig. 2

a side view of the manifold according to Fig. 1 .

Fig. 3

a section through the manifold in the level III-III in Fig. 1 .

Fig. 4

a section in the plane IV-IV according to Fig. 1 .

Fig. 5

a section in the plane VV according to Fig. 4 and

Fig. 6

a detail X according to Fig. 1 ,

Fig. 1 shows a portion of a manifold 1, which is preferably made of an aluminum material and for heat exchangers, for. B. a coolant radiator for motor vehicles is used. In the bottom (drawing plane) of the manifold 1 passages 2 are introduced with a flat oval cross section, which serve to receive flat tubes, not shown. The flat tubes, also made of an aluminum alloy, are soldered to the manifold. The manifold 1 ends the end face in a socket 1a, to which a coolant hose, not shown, can be connected. The other end of the tube, not shown, is closed at the front, z. B. by a soldered lid. The passages 2, which extend transversely to a longitudinal axis 1b of the collecting tube 1 in their longitudinal extent, are arranged at equal distances from each other, ie with a measure t, which is referred to as pipe division. Between adjacent passages 2 in the region of the pipe pitch t are flattened, with respect to the passage openings 2 raised, elongated areas 3 are arranged, which will be discussed in more detail below.

Fig. 2 shows the manifold 1 in a view from the side, ie with respect to the representation in Fig. 1 rotated by 90 ° about the axis 1 b. The raised flattened areas 3 appear here as wave peaks of a wavy line w. Between the wave crests 3 are wave troughs 4, in the region of the passages 2 (not shown here) are arranged. All wave peaks 3 are tangent to a notional plane E which is perpendicular to the plane of the drawing and has the distance x from the longitudinal axis 1b which is smaller than the radius r of the manifold 1. The wave crests 3 are thus - which will be explained in more detail below - set against the circular shape.

Fig. 3 shows a cross section through the manifold 1 in the plane III-III according to Fig. 1 , ie through a passage 2, which, viewed from the circumference, is directed inwards, ie towards the center M of the collecting tube 1. The passage 2 has in the radial direction an outer boundary in the form of the flattening 3 and an inner boundary in the form of a straight line 5, on which the longitudinal edge of the passage 2 forms. The dimension between the outer and inner boundary lines 3, 5, which run parallel to one another, is denoted by h, the draft height. At the longitudinal edge 5, a circumferential, band-shaped contact surface 6 connects radially outwardly, which is formed by two flat longitudinal and two rounded narrow sides, ie corresponding to the circumference of a flat oval or the flat tube, not shown. The flattening 3, which the wave crests 3 in Fig. 2 is opposite to the circumference of the circle radially inwardly offset - it thus forms a secant of the circle. The length of the flattening 3 corresponds approximately to the longitudinal extension of the passage 2 in the region of the contact surface 6. The manifold 1 has a wall thickness s, and the contact surface 6 has a radial extent b, which corresponds approximately to the wall thickness s. The longitudinal extension of the passages 2 is denoted by.

Fig. 4 shows a cross section through the manifold 1 in the plane IV-IV in Fig. 1 , ie in the area of the flattened area 3 and in the middle between two adjacent passages 2. The flattened area 3 appears in Fig. 4 as a cut surface, from which it is clear that the original circular cross-section of the manifold 1 is flattened in this area. The passage 2 appears in this section as a view from the outside with the inner longitudinal edge 5. The outer diameter of the manifold 1 is denoted by d = 2r.

Fig. 5 shows a section along the plane VV in Fig. 4 , ie an axial or longitudinal section through the manifold 1. Between two adjacent passages 2 is an approximately roof-shaped or V-shaped trained wall region 7 can be seen, the apex of which is formed by the flattened region 3. On both sides of the flattened region 3, conically inclined surfaces 8, 9 which run in a funnel shape towards the contact surfaces 6 extend. The illustration shows that the contact surface 6 in the region of the narrow sides is slightly offset in height relative to the longitudinal sides of the passages 2.

Fig. 6 shows the detail X Fig. 1 ie a view of the passages 2 and the flattened region 3 arranged between the passages 2, which in its extent transversely to the longitudinal axis 1b corresponds approximately to the longitudinal extent of the passages 2.

According to a preferred embodiment, the dimension I of a passage 2, d. H. Its longitudinal extent is approximately half of the outer diameter d of the manifold 1. The ratio I / d is therefore approximately 0.5. Deviations up and down are possible, where I / d is always less than 1.

According to a preferred manufacturing method, the passages 2 are freely formable, d. H. without inserting a die in the manifold 1 and without hydraulic back pressure. The passages 2 can be produced with a radially deliverable multi-stage tool (not shown), a wedge-shaped punch with cutting edge and calibration shaft. The cutting edge of the punch initially strikes the circular cylindrical circumference of the collecting tube and ruptures the tube wall. By further radial inward movement of the punch of the passage 2 shown in the above-mentioned figures is formed. The longitudinal edges 5 are formed as tear-off edges due to the free cutting process.

Claims (9)

1. Manifold (1) for a heat exchanger with a substantially circular cross-section and with inward looking, flat oval passages (2) for receiving flat tube ends, wherein deformed sections (3) are arranged between adjacent passages (2), wherein the design of the deformed sections (3) is flattened in the peripheral direction and the flattened sections (3) are each arranged in the centre between adjacent passages (2) and the length of the flattened sections (3) in the peripheral direction approximately corresponds to the length of the longitudinal sides (5) of the passages (2), wherein seen in the longitudinal direction (1b) of the manifold (1) and adjacent to the flattened sections (3), angular surfaces (8, 9) sloping towards the passages (2) are arranged and the passages (2), based on the flattened sections (3), have a substantially constant height h, especially in the section of the longitudinal edges (5) and the longitudinal sides of the passages (2) each have tear-off edges (5), characterised in that the height of the passages (2) in the section of the narrow sides is lower than in the section of the longitudinal sides (5).
2. Manifold according to claim 1, characterised in that the deformed sections (3), viewed from the longitudinal view, are approximately formed in a roof-or V-shape (7, 8, 9).
3. Manifold according to one of the preceding claims, characterised in that the flattened sections (3) are tangent to a fictional plane E, which forms a flattening of the circular cross-section of the manifold (1).
4. Manifold according to one of the preceding claims, characterised in that the passages (2) have a circumferential, ribbon-shaped contact area (6) on the inside thereof which has a height b corresponding to the wall thickness s of the manifold (1).
5. Manifold according to claim 4, characterised in that the contact area (6) can be soldered to the flat tube end.
6. Manifold according to one of the preceding claims, characterised in that the length 1 of the passage and the diameter d of the manifold (1) form a ratio l/d which is in the range between 0.3 and 1, preferably in a range between 0.4 and 0.6.
7. Manifold according to one of the preceding claims, characterised in that the passages (2) can be produced with a tool which is deliverable in the radial direction, especially a multilevel cutting and calibrating stamp.
8. Use of the manifold (1) according to one of the preceding claims for a condenser of an air conditioning system or a coolant cooler of a cooling circuit for a vehicle.
9. Heat exchanger comprising a manifold (1) according to one of claims 1 to 7, characterised in that tube ends of flat tubes are arranged inside the passages (2) and soldered to the passages.

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