GB2120769A

GB2120769A - Heat exchanger in particular a radiator for motor vehicles

Info

Publication number: GB2120769A
Application number: GB08312689A
Authority: GB
Inventors: Hans Martin
Original assignee: Behr GmbH and Co KG
Current assignee: Mahle Behr GmbH and Co KG
Priority date: 1982-05-25
Filing date: 1983-05-09
Publication date: 1983-12-07
Also published as: FR2527761A1; GB8312689D0; ES271365Y; GB2120769B; ES271365U

Abstract

A radiator for motor vehicles, has disposed parallel with one another and discharging into an upper and a lower water tank 4, 5 a plurality of tubes 3 for carrying a heat exchange medium and having, arranged perpendicular to the tubes, heat exchanger fins 2 which are connected to the tubes rigidly in solder-free fashion, and having, disposed in solder-free manner on both side faces 6, 7, side parts 8, 9 on which are disposed holders 14, 15, 16 for attachment of the heat exchanger to a motor vehicle or the like, characterised in that both side parts are clamped to one another via at least one tie rod 11 and are held frictionally against the side faces. Wedge surface 10 is used to tension the tie-rod 11. <IMAGE>

Description

SPECIFICATION Heat exchanger, in particular a radiator for motor vehicles The invention relates to a heat exchanger, in particular a radiator for motor vehicles, having disposed parallel with one another and discharging into an upper and a lower water tank, a plurality of tubes for carrying the heat exchange medium and having, disposed at a right-angle to the tubes, heat exchanger fins which are connected to the tubes rigidly but in solder-free fashion, and having, disposed in solder-free manner on both side faces, side parts on which are disposed holders for attachment of the heat exchanger to a motor vehicle or the like.

Generally, such so-called round tube heat exchangers are constructed so that they can be assembled together without soldering. The side parts are not soldered on but are normally held in form-locking fashion on the heat exchanger fins of the fin block. Such an attachment of the side parts is described, for example, in French Patent No. 2 145 383.

There, notches are provided in the heat exchanger fins into which are bent the lugs which are constructed on the side parts after these have been fitted, so creating a formlocking connection. It is also known (from German Offenlegungsschrift No. 24 18 132) to provide on the end faces of the heat exchanger fins dovetailed stamped-out recesses into which then corresponding lugs bent out from the surface plane of the side parts engage and so produce a form-locking connection. These known fixing methods make it possible with what is referred to as solder-free heat exchangers, rigidly and reliably to secure the side parts but they are complicated in that a corresponding notch or recess must be provided on the heat exchanger fins. Furthermore, bending over of the lugs which engage into the recesses or notches constitutes an additional operation in manufacturing of the heat exchanger.

The invention is based on the problem of providing a heat exchanger, in particular a radiator for motor vehicles, in which it is possible to secure the side parts in an extremely simple manner.

The invention resides in that both side parts are clamped to one another via at least one tie rod and are held frictionally against the side faces. This construction means it is no longer necessary in some subsequent operation to establish a form-locking connection between the side parts and the fin block of the heat exchanger. Therefore, the side parts can be mounted on the side faces and are then clamped to one another via tie rods. This provides for an extremely simple fitment of the side parts. When the side parts are clamped to one another, there is a frictional connection between the heat exchanger fins and the side parts which can withstand the necessary fixing forces which arise due to fixing on a motor vehicle or the like via the holders provided on the side parts.

In a favourable further development of the invention, it is envisaged to provide on at least one side part and at a distance corresponding substantially to the width of the side face, two oppositely disposed walls which project outwardly at a right-angle to the side face, through which the free ends of the tie rods can have their hook-shaped bent-over ends passed and clamped. The walls represent the points of attack of the tie rods and so permit of a simple operative connection between the tie rods and the side parts.

In a very advantageous further development of the invention, it is envisaged for at least one of the walls to be provided with at least one wedge-shaped surface rising away from the side face for clamping of the tie rod.

Thus, the free ends of the tie rod can initially be engaged on one zone at the commence; ment of the wedge-shaped surface and then clamped by being pushed up along the wedge-shaped surface. In consequence, the clamped condition of the tie rod can be very easily achieved. It is also advantageous if the tie rod or rods can be secured to the wedgeshaped surface in self-locking and/or formlocking manner. Then no special elements are necessary to avoid the tie rod slipping on the wedge-shaped surface.

It is also advantageous if the tie rods are constructed as clamping means encircling the fin block formed by the heat exchanger fins and engaging the walls of a side part. Then only one tie rod is required which, starting from one side part, is passed around the fin block and the oppositely disposed side part, its other free end being again suspended in the other wall of the side part. Then, a wedgeshaped surface is only required on one side part. It is naturally also conceivable to use two tie rods which then in each case on one side clamp the side parts together.Similarly in the case of relatively large-area heat exchangers, two encircling tie rods may be used which extend at a distance from each other in the longitudinal direction of the side face and which are then likewise clamped in corresponding walls via the wedge-shaped surfaces or other means.

If encircling tie rods are used, it is also sufficient to provide one of the two side parts with the wedge-shaped surfaces and to have the tie rod passing around it in such a way to rest directly on the surface of the other side part. The side part which is not provided with the wedge-shaped surface can then be very simple in construction.

For securing the side parts transversely to the longitudinal direction of the side faces, i.e.

at a right-angle to the end faces of the radia tor, it is convenient if the side parts are provided with angled-over edges engaging laterally around the heat exchanger fins. The bent-over edges of the side parts then bear laterally on the heat exchanger fins so that the side parts are held immovably in the indicated direction.

With regard to manufacture, it is convenient if the angled-over edges of the side part provided with the wedge-shaped surfaces are constructed as lugs stamped out from the basic surface and bent through 90 . Thus, the material of the basic surface is also used for the lugs, which are advantageously so constructed that the lugs on one side of the side part are staggered in relation to the lugs on the other side. The stability of the side part is then not adversely affected. The angled-over edges on the side part which is not provided with the wedge-shaped surface can be constructed as continuous walls or similarly as correspondingly constructed lugs.

A further advantageous development of the invention envisages disposing on the side part which is not provided with the wedge-shaped surface two abutments which are disposed at a distance from each other corresponding to the width of a tie rod. Thus, the tie rod is placed immovably over this side part and is secured against displacement in the longitudinal direction of the side parts.

With regard to assembly, it is particularly suitable if the tie rod is a steel strip which is then, in the manner described above, easily placed around the heat exchanger fin block and appropriately engaged.

The invention is described in greater detail hereinafter with reference to an embodiment shown in the accompanying drawings, in which: Figure 1 is a side view of a heat exchanger according to the invention: Figure 2 shows a section through the heat exchanger taken on the line ll-ll in Fig. 1; Figure 3 is a section through a side part of the heat exchanger taken on the line Ill-Ill in Fig. 1, and Figure 4 is a diagrammatic partial view similar to Fig. 1 but with precurved side parts which can be pressed under initial tension against the side faces.

The heat exchanger 1 shown in Fig. 1 may be used as a radiator in a motor vehicle. A coolant, for example water, is passed through the round tubes 3 which extend between the two water tanks 4 and 5. At a right-angle to the tubes 3 and at short intervals there extend plate-like heat exchanger fins 2 which are rigidly connected to the tubes which pass through them.

The heat echanger such as is shown in Fig.

1 is assembled in a solder-free manner.

Mounted on the side faces 6 and 7 of the heat exchanger 1 are side parts 8 and 9 which are provided with holders 14, 15 and 16 via which the heat exchanger can be fixed in a motor vehicle. The side parts 8 and are clamped to one another via tie rods, which in the example illustrated is a steel strip 11, and are thus held on the relevant side faces 6, 7 of the fin block by a frictional connection. As can be seen in Fig. 1, the side part 8 has, rising away from the surface of the side part 6, a wedge-shaped surface 10 which serves for tensioning of the tie rod, as will be explained in greater detail hereinafter.

As Fig. 2 shows, the side part 8 has, constructed on the two longitudinal edges of the side parts and protruding at an angle of 90 from the surface of the side part, walls 8a, 8b, the distance apart of which corresponds substantially to the width of side face 6. In the region which can be seen in Fig. 1, these walls are provided with the wedgeshaped surface 10. Furthermore, the side part 8 has oppositely disposed staggered lugs 1 2 by which it engages laterally around the heat exchanger fins 2. The (in Figs. 1 and 2) lower side part 9 is C-shaped and similarly has angled-over edges 1 3 which engage laterally around the heat exchanger fins 2 so that both side parts are secured transversely of the longitudinal direction of the side faces.

The tie rod 11 is constructed as an encircling steel strip having two free ends 11 a, 11 b which are bent over in the shape of a hook and which are engaged on the side part 2 via the walls 8a, 8b. This steel strip 11 is guided over the surface of the side part 9 and presses the two side parts towards each other when the free ends which are initially placed loosely over the walls 8a, 8b, more or less at the commencement of the up slope of the wedgeshaped surface 10, are pushed up the wedgeshaped surface 10 and are thus tensioned.As in this example only one encircling tie rod is used-in the case of relatively large heat exchangers naturally, it is also conceivable to use two or more encircling tie rods-the wedge-shaped surface is so constructed that in the tensioned condition, the steel strip 11 extends substantially in the centre of the longitudinal extent of the side parts 8, 9 and parallel with the direction of the heat exchanger fins, so that over their length, the side parts are applied regularly against the heat exchanger fins ensuring that a good frictional connection is achieved.

The wedge-shaped surface 10 is not absolutely necessary. It may be sufficient to construct the walls so that they extend flat and to achieve tensioning of the tie rod when the free ends are bent over. Naturally, too, it is not essential for the walls to project from the longitudinal edges of the side parts, since it is also conceivable to secure side parts which are wider than the lateral faces of the heat exchanger fin block. Then the walls for engagement of the tie rod could be obtained at suitable locations at a distance corresponding substantially to the width of the side face, for example by being bent up out of the basic surface.

Secured rigidly on the side part 9 are two holders 14 and 1 6 which leave between them a gap corresponding to the width of the steel strip 11. These holders form two abutments disposed laterally of the steel strip so that the steel strip is guided and cannot shift in the longitudinal direction of the side parts.

Upon engagement of the tie rod, this is first placed with the corresponding portion in the guide created between the holders 14 and 16, its bent-over end being engaged in the region of the upward rise of the wedgeshaped surfaces 10. In this starting position, it extends obliquely between the side parts.

Afterwards, its free ends are displaced along the wedge-shaped surface 10 until it occupies the position shown in Fig. 1. Instead of the holders 14 and 16, it would also be possible to provide a depression on the side part 9 which form a guide for the tie rod.

The angle of inclination of the wedgeshaped surface 10 and the manner in which it extends in the region in which the tie rod occupies its final position is such the tie rod is self-lockingly seated. Naturally, it is also possible to provide additional securing elements such as, for example, caulking in the plank of the side part to provide a certain form-locking connection.

Fig. 3 shows that the lugs 1 2 which are disposed in an offset relationship on the two sides of the side part 8, are stamped out of the basic surface of the side part 8 and are bent downwardly. This side part is thus very easily produced. Also a part forming a holder 1 5 can be constructed on the walls 8a, 8b so that no additional holders are required which would have to be mounted on the side part 8.

Naturally, it is also possible, instead of a continuous steel strip, to dispose two steel strips extending in each case on one side, although this would mean that the side part 9 would have to be provided with walls constructed in accordance with the walls 8a, 8b of the side part 8, for engagement of the two ends of these steel strips, the said ends having likwewise to be bent over into a hook shape. Then, too, the side parts could be reliably secured in an extremely simple manner without special tools.

Fig. 4 shows diagrammatically that the side parts 8' and 9' are of different lengths and may be constructed as pre-curved brackets of elastic material which can have their ends 8a applied against the associated side face 6, 7 and which after assembly can bear with initial tension against the side faces 6, 7. By reason of the tie rod or rods 11', the outwardly curved middle parts are then drawn inwardly until they, too, are bearing on the side faces.

With appropriate dimensioning, it is thus possible to achieve even pressures over the total length of the side parts 8', 9' to produce the desired frictional connection.

well for correspondingly shaped sheet metal side parts. If the tubes 2 are offset in their disposition in relation to one another (see Fig.

4b), the rod 1 9 between the heat exchanger fins need not extend parallel with the end face, as shown in Fig. 4b. The diameter of the bores 23 is somewhat larger than the diameter of the rod 19, to simplify pushing of the rod 1 9 through the bores. Since the distance between adjacent heat exchanger fins is normally less than the diameter of the rod, the heat exchanger fins between which the rod is pushed will be bent somewhat apart, which has no effect of any kind on the functioning of the heat exchanger.

Furthermore, walls 24, 25 are integrally moulded on and project upwardly from the surface of the side part halves, bores 1 6 opposite one another and through which fixing of the heat exchanger is possible, are incorporated into the walls 24 which are aligned in the direction of the groove. The walls 25 which extend transversely to the direction of the groove 6 extend obliquely in the direction of the groove 6 so that, upon insertion of the lugs 8a into the groove 6, a pivoting movement of the two side parts in respect of each other remains possible.

Claims

1. Heat exchanger, in particular a radiator for motor vehicles, having disposed parallel with one another and discharging into an upper and a lower water tank, a plurality of tubes for carrying the heat exchange medium and having, arranged perpendicular to the tubes, heat exchanger fins which are connected to the tubes rigidly in solder-free fashion, and having, disposed in solder-free manner on both side faces, side parts on which are disposed holders for attachment of the heat exchanger to a motor vehicle or the like, characterised in that both side parts are clamped to one another via at least one tie rod and are held frictionally against the side faces.

2. Heat exchanger according to Claim 1, characterised in that oppositely disposed on at least one side part and at a distance corresponding approximately to the width of the side face and projecting at a right-angle to the side face there are walls through which the free hook-like bent over ends of the tie rods are engaged and tensioned.

3. Heat exchanger according to one of Claims 1, and 2, characterised in that at least one of the walls is provided with at least one wedge-shaped surface rising away from the side face for tensioning of the tie rods.

4. Heat exchanger according to Claim 3, characterised in that the tie rods are secured on the wedge-shaped surface in a positive and/or self-locking manner.

5. Heat exchanger according to one of Claims 1 to 4, characterised in that the tie rods are constructed as tensioning means passing around the fin block formed by the heat exchanger fins and engaged on the walls of a side part.

6. Heat exchanger according to one of Claims 1 to 5, characterised in that one of the two side parts is provided with the wedgeshaped surface and in that the tie rod passes around in such a way as to rest on the surface of the other side part.

7. Heat exchanger according to one of Claims 1 to 6, characterised in that the side parts are provided with angled-over edges which engage laterally around the heat exchanger fins.

8. Heat exchanger according to Claim 7, characterised in that the angled-over edges of the side part which is provided with the wedge-shaped surface are constructed as lugs stamped out of a basic surface and bent over through 90

9. Heat exchanger according to Claim 8, characterised in that the lugs are provided on one side of the side part and are staggered in respect of the lugs on the other side.

10. Heat exchanger according to one of Claims 1 to 9, characterised in that on the side part which is not provided with the wedge-shaped surface, there are two abutments which are disposed at a distance apart which corresponds to the width of one tie rod.

11. Heat exchanger according to one of Claims 1 to 10, characterised in that the tie rod provided is a steel strip.

12. Heat exchanger according to Claim 1, characterised in that at least one side part is constructed as a curved bracket of elastic material which has its ends pressing on the associated side face and which is applied with pretension against the side face.