EP1811259B1 - Fastening assembly for heat exchangers - Google Patents

Abstract

The assembly has a collector box (2) made of a castable material e.g. plastic, and a tube base (3) made of a ductile material e.g. metal. The tube base has a circulating, ductile boundary region (3b), and the collector box has a circulating flange (2d), where the boundary region is mechanically connected with the flange. An O-ring (9) is disposed between a lateral region of the flange and the boundary region of the tube base.

Description

The invention relates to an arrangement for fastening a collecting tank on a tube plate of a heat exchanger according to the preamble of claim 1.

Such mounting arrangements are known as connections between a tube sheet and a collecting box for heat exchangers in various forms. The type of connection depends on the selected materials of the tube plate on the one hand and the header box on the other. Are both parts of the compound of the same material, eg. As plastic or aluminum sheet, a cohesive, compound by welding or soldering is preferred. For different materials, eg. B. a plastic box and a tube sheet made of metal, for. As aluminum, come mechanical connections, so-called flare with inserted seal used. In this case, a closed sealing frame is inserted into a circumferential groove of the tube sheet, the collecting box is placed on the sealing frame and clamped to the ground by Umbördein the edge region of the soil. This gives a tight connection between a plastic box and a metal floor. Such box / floor connections have been known by the following publications of the applicant: DE 28 52 408 B2 . DE 28 52 415 B2 as well as the DE 38 41 470 A1 , In the former document, the DE 408 , Slits are introduced into the edge area of the floor (by punching), and the outermost edge area arranged above the slots becomes during assembly pressed from the box and floor over a circumferential flange of the box. This box / floor connection is referred to as a so-called Wellenschlitzbördelung, which is also in the latter document, DE '470, in a modified form. In DE '415, no slots are made in the edge area of the floor, but the edge area is partially bent over the flange of the box. In the known compounds, the water tank (collecting tank) is loaded with a vertical closing force, ie perpendicular to the plane of the tube sheet. The sealing force also works in this direction. A disadvantage of the known mounting arrangements that the tube sheet - seen in the air flow direction - each protrudes beyond the end faces of the tube / rib block, ie the width of the tube sheet is greater than the so-called block dimension in the depth direction. This results in an increased depth for the heat exchanger.
In particular, with increasing pressure in the known collecting tanks there is a risk that they will detach from the anchorage. This can in particular reduce the clamping force of the seal.

It is an object of the present invention to provide an arrangement for fastening a collecting tank on a tube plate of a heat exchanger of the type mentioned, which has a smaller overall depth of the heat exchanger result.

This object is solved by the features of claim 1. According to the invention, it is provided that the seal between the box and the tube bottom is arranged laterally on the box, ie in the region of the side walls of the box, and overlapped by the erected edge region of the base. The seal, preferably an O-ring thus enclosing the circumference of the box and is preferably arranged for guiding in a circumferential groove. The tubesheet, abuts with its edge region from the outside to the seal and exerts due to the mechanical connection of the soil with the box also the required sealing force. This sealing or pressing force is exerted essentially in a plane which is arranged approximately parallel to the plane of the tube bottom. When using an O-ring, which is guided in a corresponding groove is, no high sealing force is required, but only a slight deformation of the O-section. The advantage of the box / floor connection according to the invention lies in the reduced depth compared to the prior art. The arrangement of the seal on the side walls of the header box eliminates existing in the prior art circumferential groove in the tube sheet in which the seal was added. Due to the arrangement according to the invention, the tube sheet without such a groove, ie up to the peripheral, erected edge region can be formed flat, so that the passages for receiving the tubes can extend to the edge region. Thus, the block dimension, ie the depth of the tube / rib block corresponds approximately to the depth of the bottom or of the box received in the bottom. In particular, when using the heat exchanger according to the invention in a motor vehicle, for. As a coolant radiator for cooling an internal combustion engine, the reduced overall depth has a particularly advantageous effect.

Further advantageous embodiments of the invention will become apparent from the dependent claims. The seal between the box and the floor can also be designed as a pasty seal, which is applied in a doughy form on the box and hardens after connection to the tube sheet. Suitable sealing materials are, for example, silicone or a two-component plastic.

According to an advantageous embodiment of the invention, the edge region of the bottom has a lateral sealing region, to which a fastening region adjoins. The sealing area is smooth and abuts the seal with a certain preload, while the mounting area is deformable and serves to establish a mechanical connection between the box and the floor.

According to a first embodiment, the attachment portion for this purpose has T-shaped punched out locking elements, which are deformed after insertion of the box in the ground to U-shaped locking elements ("claws"), which engage with the box grooves and with the side walls of the box protruding ribs. By the U-shaped deformed locking elements, the box is on the one hand in the longitudinal direction of the tubes of the heat exchanger, ie secured perpendicular to the tube bottom plane and on the other hand transversely to this direction, ie in a plane parallel to the tube bottom.

According to a second embodiment, the fastening region of the tube plate is designed as a locking strip with a continuous outer edge and punched openings, which is bent around the flange of the box and fixed there by means of anchoring elements. In order for a positive connection between the edge region of the tube sheet and the flange of the box is made.

According to a further advantageous embodiment of the invention, the tube sheet passages for receiving pipes, in particular of flat tubes, wherein the passages are formed either to the side of the box or to the opposite side, d. H. the collar of the passages points either to the box or in the direction of the tube / rib block. In the latter case, a maximum length for the passages, which extend over the entire width of the soil and reach up to the wall of the edge region of the soil. Thus, the collar of the passage on the narrow sides in the wall of the edge area over. Thus, a maximum tube depth or block depth for the tube / rib block in relation to the bottom width can be achieved. The block depth thus corresponds approximately to the overall depth of the heat exchanger.

According to a further advantageous embodiment of the collection box and the tube sheet are self-locking connected to each other. Particularly advantageous, in particular with increasing pressure, a seal can be pressed more strongly against the tubesheet and the collecting box. In particular, pressure that would lead to loosening of the tube plate from the header, be converted into a self-locking clamping force.

Fig. 1

eine erfindungsgemäße Befestigungsanordnung für einen Kasten und einen Rohrboden eines Wärmeübertragers,

Fig. 2

einen vergrößerten Ausschnitt der Befestigungsanordnung aus Fig. 1,

Fig. 3

den Rohrboden vor dem Einsetzen des Kastens,

Fig. 4

den Rohrboden mit verformtem Randbereich nach dem Einsetzen des hier nicht dargestellten Kastens,

Fig. 5

den Kasten mit eingelegter Dichtung und Querschnitt in 3-D-Darstellung,

Fig. 6

einen Schnitt durch den Kasten mit eingelegter Dichtung,

Fig. 7

einen Querschnitt durch den Kasten und den Rohrboden mit Durchzug,

Fig. 8

ein zweites Ausführungsbeispiel für eine Kasten/Boden-Verbindung mit Rohrboden,

Fig. 9

den Kasten mit Verankerungselementen und

Fig. 10

einen vergrößerten Ausschnitt der Verbindung zwischen Rohrboden und Kasten.

Embodiments of the invention are illustrated in the drawings and will be explained in more detail below. Show it

Fig. 1

a fastening arrangement according to the invention for a box and a tube plate of a heat exchanger,

Fig. 2

an enlarged section of the mounting arrangement Fig. 1 .

Fig. 3

the tubesheet before inserting the box,

Fig. 4

the tubesheet with deformed edge region after insertion of the box, not shown here,

Fig. 5

the box with inlaid seal and cross-section in 3-D representation,

Fig. 6

a section through the box with inserted seal,

Fig. 7

a cross section through the box and the tube sheet with passage,

Fig. 8

a second embodiment of a box / floor connection with tube sheet,

Fig. 9

the box with anchoring elements and

Fig. 10

an enlarged section of the connection between the tube sheet and box.

Fig. 1 shows a heat exchanger 1, partially shown, which a collection box 2, hereinafter also referred to as a short box called a tube plate 3, hereafter also called bottom, and a tube / rib block 4, hereinafter also referred to as a short block. The heat exchanger 1 can be used as a coolant radiator for cooling an internal combustion engine of a motor vehicle or as a radiator heating and air conditioning of a motor vehicle - it is flowed through in this case of coolant and secondary side acted upon by ambient air. The box 2 is preferably made of plastic, ie formed as a molded part. Likewise, however, is a preparation of metal, for. B. a Leichtmetalldruck- or injection molding possible. The collection box 2 is, as will be shown and explained in more detail below, formed as a box-shaped hollow body, which has a longitudinal side 2a with molded ribs 5 and a narrow side 2b, also with molded ribs 5. (the two opposite sides are not visible in this representation and therefore not marked). The collecting box 2 thus has a substantially rectangular floor plan with rounded corners. Of the Collector 2 has at its top a nozzle 2c for the entry or exit of a heat exchange medium, for example, the coolant of a cooling circuit of an internal combustion engine. The tube sheet 3 is made of a metal sheet, preferably aluminum sheet without cutting and takes the pipes of the block 4, not shown. The tube plate 3 has on its upper side U-shaped locking elements 6 (so-called claws), which - which will be explained - are in engagement with the ribs 5.

Fig. 2 shows an enlarged section of the attachment of collection box 2 and tube sheet 3 in another isometric view. The U-shaped deformed locking elements 6 are part of the bottom 3, pass through a groove 5 arranged in the groove 5 a and lie with their U-legs on both sides of the rib 5 at.

Fig. 3 shows in a 3-D representation of the open bottom 3, ie before the connection to the box 2, which is not shown here. The tube plate 3 has an approximately rectangular planar bottom portion 3a, are received in which tube ends 7 of flat tubes of the block 4, not shown. The flat tube ends 7 extend recognizably over the entire width (depth) of the bottom region 3a. The bottom region 3 a surrounds an approximately vertically erected circumferential edge region 3 b, which has a multiplicity of T-shaped locking elements 6 'on its outer edge. The tube sheet 3 is preferably made of an aluminum sheet, ie made of a board, wherein the T-shaped locking elements 6 'are punched out before the edge region 3b is set up.

Fig. 4 shows the "closed" tube sheet 3 with U-shaped locking elements 6, which are formed by deformation of the T-shaped locking elements 6 '. However, this transformation takes place after placing the box 2, which is omitted here - for better illustration.

Fig. 5 shows the box 2 in a 3-D representation and a cross section through the two longitudinal sides 2a, at the foot of a circumferential groove 8 is arranged for receiving a round cord seal 9. The groove 8 is used for positioning and guiding the round cord seal 9, also called O-ring, during assembly of the box 2, ie when inserted into the open bottom 3, as in Fig. 3 is shown.

The round cord seal 9 is a closed, preferably molded from an elastomer sealing frame which is inserted with slight bias in the groove 8. The corner areas of the box 2 and the tube bottom 3 are sufficiently rounded to ensure proper installation of the seal on both sides.

Fig. 6 shows a cross section through the collecting box 2 with longitudinal sides 2a, groove 8 and inserted round cord seal 9. The long sides 2a - this also applies to the narrow sides 2b not shown here - are thickened in their foot to a flange 2d, in which the groove 8 is introduced , As can be seen from the drawing, the groove 8 is open to the outside, but the sealing frame 9 can not fall out of the groove 8 after insertion due to its bias. Above the flange 2d, the ribs 5 are arranged, which have on their underside an approximately rectangular groove 5a formed. The box 2 is - as mentioned - used with inserted round cord seal 9 in the open bottom 3.

Fig. 7 shows the finished connection (mounting arrangement) between box 2 and tube sheet 3, with U-shaped locking elements 6, which rest on the top of the flange 2d. During assembly, the tube sheet 3 is inserted with its locking elements 6 'in the grooves 5a until the upper edge of the flange 2d below the lower edge of the locking elements 6' is - then the locking elements-6 'are bent inwardly around the respective ribs 5, so that they include these as U-shaped locking elements 6. Box 2 and bottom 3 are thus fixed against each other in all directions. As already mentioned, the round cord seal 9 is slightly deformed by the system on the inside of the edge region 3b in the manner of an O-ring, so that the required Sealing effect is achieved without requiring a relatively high contact pressure would be required. Alternatively, however, instead of an O-ring 9, a pasty seal, for example based on silicone, can be used. Likewise, a two-component plastic can be deposited in a corresponding groove, wherein the plastic cures after application to air. In one development, the two-component plastic is introduced into a groove, for example, by means of a two-component plastic injection technique. We first introduce a first component and then the second component, in particular injected. In another embodiment, the two components are mixed and then introduced into the groove, in particular injected. The bottom 3, ie the flat bottom portion 3 a, has passages 10 for receiving flat tubes 11, which communicate with the interior of the collecting box 2 and are part of the above-mentioned block 4. The passages 10 are - as known per se - produced by punching and Kragenziehen, wherein the collar of the passages 10 are formed in this embodiment, to the side of the block. This results in a maximum clear width Di of the passage 10 (corresponds to the depth of the flat tube 11). The outer dimension of the passage 10 is denoted by Da and corresponds to the width of the bottom 3. The collar of the passage 10 is thus in the edge region 3b of the bottom 3 over. The block depth of the heat exchanger, which corresponds approximately to the dimension Di, is thus only slightly smaller than the bottom width Da, more precisely, only by twice the bottom wall thickness less.

In deviation from the illustrated embodiment, in particular the T-shaped locking elements 6 'and the U-shaped locking elements 6 formed therefrom, as an alternative, a so-called Wellenschlitzbördelung, as described in the cited document of the applicant DE 25 52 408 B2 is described.

FIGS. 8, 9 and 10 show a further embodiment of the invention for a mounting arrangement of a box with a tube sheet of a heat exchanger. Fig. 8 shows a (closed) bottom 12, which is placed on pipe ends 13 of a tube / rib block 14. The tube sheet 12 has a circumferential edge region 12a arranged at the outer edges Locking strips 15, which are notched in the corner areas. Fig. 9 shows a collection box 16, which with respect to circumferential groove 8 and inserted round cord seal 9 corresponds to the previous embodiment (therefore, the same reference numerals). The collecting box has a circumferential flange 16a with a top 16b on which anchoring elements 17 are arranged in the form of a series of teeth.

Fig. 10 shows an enlarged section of the finished connection, ie the locking bar 15 in engagement with the anchoring elements 17 on the box 16. The locking bar 15 of the tube sheet 12 has a continuous outer edge 15a and behind arranged openings 15b, which in the form and arrangement of the toothed rack anchoring elements 17 correspond. After the box 16 has been inserted into the open floor 12, the four circumferentially arranged locking strips 15 are bent inwardly such that the teeth 17 pass through the openings 15b in the locking strip 15 and thus bring about a positive connection. The sealing of collecting tank and tube sheet takes place in the same manner as in the previous embodiment: The edge region 12a of the bottom 12 exerts a (in the drawing) horizontal contact pressure on the O-ring 9, ie approximately parallel to the plane of the tube bottom 12th

Claims (15)

1. Assembly for fastening a header box (2) to a tube plate (3) of a heat exchanger, wherein the header box (2) can be made of a material that can be cast, in particular a plastic, and the tube plate (3) of a deformable material, in particular metal, the tube plate (3) having a raised, all-round edge area (3b) and the header box (2) having an all-round flange (2d) such that a seal (9) can be arranged between the tube plate (3) and the flange (2d) and the said edge area (3b) can be mechanically connected to the flange (2d), characterised in that the seal (9) can be arranged between a lateral part (8) of the flange (2d) and the raised edge area (3b) of the tube plate (3).
2. Assembly according to Claim 1, characterised in that the lateral part of the flange (2d) has an all-round groove (8) in which the seal (9) is held.
3. Assembly according to Claims 1 or 2, characterised in that the seal is in the form or a loop or O-ring (9).
4. Assembly according to any of the preceding claims, characterised in that the seal consists of a pasty sealing material that can be laid into the groove (8) and hardens therein.
5. Assembly according to any of the preceding claims, characterised in that the seal can be made of silicone or a two-component plastic.
6. Assembly according to any of the preceding claims, characterised in that the edge area (3b) of the tube plate (3) has a lateral sealing area against which the seal (9) rests, and a fastening area (6) which overlaps the flange (2d0, which is joined to the header box (2).
7. Assembly according to Claim 6, characterised in that the header box (2) has longer sides (2a) and shorter sides (2b), and the fastening area (6) of the tube plate (3) is connected, preferably with shape interlock, to the said longer and shorter sides (2a, 2b).
8. Assembly according to Claims 6 or 7, characterised in that the fastening area comprises locking elements (6', 6) stamped to form a T-shape that can be deformed to a U-shape and the longer sides (2a) of the header box (2) have projecting fins (5) with grooves (5a), and the said locking elements (6) engage with the said grooves (5a).
9. Assembly according to Claim 8, characterised in that in each case one U-shaped locking element (6) engages in one groove (5a).
10. Assembly according to Claims 6 or 7, characterised in that the fastening area is formed as a locking strip (15) with openings (16b) stamped out of it, anchoring elements (17) are arranged above the flange (16a) of the header box (16), and the locking strip (15) overhangs the upper side (16b) of the flange (1a) in such manner that the anchoring elements (17) engage in the openings (16b).
11. Assembly according to Claim 10, characterised in that the locking strip (15) is bent outwards in its corner areas.
12. Assembly according to any of the preceding claims, characterised in that to receive tubes, in particular flat tubes (11), the tube plate (3) has passages which are formed on the side facing towards the header box (2).
13. Assembly according to any of the preceding claims, characterised in that the tube plate (3) has passages (10) which are formed on the side facing away from the header box (2).
14. Assembly according to Claim 13, characterised in that the passages (10) have longer and shorter sides, and the wall of the passages (10) on their shorter sides merges into the edge area (3b) of the tube plate (3).
15. Assembly according to any of the preceding claims, characterised in that the header box (2) and the tube plate (3) can be connected to one another in a self-locking manner.

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