This problem is solved by a heating or airconditioning system for a motor
vehicle having the features of Claim 1. The basic advantages of the invention reside in the fact that the fan and the heating heat exchanger are arranged directly adjacent to one another and the free spaces resulting from the configuration of the volute housing are used for the arrangement of air ducts or connection tubes. The outside dimensions of a heating or air-conditioning system are thus reduced to a minimum.
The heating heat exchanger is preferably arranged in the housing in such a manner that it has, on its side lying in the immediate vicinity of the fan volute. a water tank which is provided with receiving connection pieces for the connection tubes, which pieces are located to the side of the portion of the fan volute. The flat water tank contour can thus be placed very close to the fan volute, the receiving connection pieces for the connection tubes, which always require corresponding space, lying in the spaces which are in any case formed to the side of the fan volute 4 and which cannot be used for guiding air in the fan.
A preferred development of the subject-matter of the invention consists in forming on the side of the heating heat exchanger remote from the fan a bypass duct which can be closed by means of an air flow control flap. Because the bypass duct is in that position, the path for the fresh air or cold air is slightly longer than the path of the air stream, the socalled hot air, conveyed through the heating heat exchanger. This has the advantage that the flow resistance of the heating heat exchanger is at least partly compensated for by the shorter flow path.
In an especially preferred embodiment, the housing is provided with an inner housing which has at least one air inlet opening and at least one air outlet opening. The heating heat exchanger is arranged in the inner housing. as a result of which, apart from the air inlet and air outlet openings, the heating heat exchanger is encapsulated. This prevents the cold or fresh air flowing through the bypass duct from being heated inadvertently by the heat radiation of the heating heat exchanger.
It is considered especially advantageous that the bypass duct is formed between the inner wall of the housing and the outer wall of the inner housing and at least one portion of the bypass duct extends approximately parallel to the end face of the heat exchanger. Thus, the walls of the housing parts simultaneously form the bypass duct and, as a result of the portion running parallel to the end face, the housing has a narrow construction. Since the bypass duct runs past the side of the heating heat exchanger remote from the fan, there is a curved portion of approximately 900 upstream of the parallel-running portion of the bypass duct. As a result of the parallelextending wall portions of the housing and inner housing, the cross-section of the bypass duct is approximately constant over its entire length. It is especially advantageous to arrange the air flow control flap in the curved portion of the bypass duct, the flap body being formed in a curved manner about its pivot axis. Thus, when the air flow control flap is open, it is in a position which corresponds to the curved contour of the housing or inner housing, so that the air flow is influenced favourably by the curved portion of the bypass duct.
6 In order to control the air flow portion of the hot air, the air conveyed through the heating heat exchanger is preferably adjusted by means of an air flow control flap mounted pivotably in the region of the air inlet opening. The air inlet opening is advantageously arranged in a region of the inner housing remote from the fan, and the air outlet opening is arranged in a diagonally offset manner with respect to the air inlet opening, relative to the direction of air flow through the heating heat exchanger. As a result of this diagonally offset arrangement of the air inlet and air outlet openings, the end face of the heating heat exchanger is acted upon in such a manner that there is an even temperature profile, although the cross-sections of the air inlet and air outlet openings are substantially smaller than the end face of the heat exchanger system.
In order to prevent the air which flows through the bypass when the air inlet opening of the inner housing is closed from entering the inner housing through the air outlet opening and absorbing heat energy from the heating heat exchanger, guide components which extend at least approximately transversely to the direction of the adjacent portion of the bypass duct are provided in the air outlet opening. These guide components also have 7 the effect that, when the air inlet opening of the inner housing is open, the hot air is discharged at the air outlet opening substantially transversely to the air flow direction of the cold air guided in the bypass duct. Thus, some of the hot and cold air is mixed and some of the hot air is expelled in the direction towards the outlet connection pieces which are connected to the discharge ports for the foot area or the windscreen defrosting system.
As the heating requirement increases, the amount of air flowing through the heating heat exchanger is to be increased and, accordingly, the amount of cold air flowing through the bypass duct is to be reduced. To ensure, in a simple manner, a corresponding dependence in the influencing of the air flows, it is advantageous for the air flow control flap in the air inlet opening and the air flow control flap in the bypass duct to be connected to one another mechanically in such a manner that an increase in the air flow through the air inlet opening leads to a reduction in the air flow through the bypass and vice versa. In order to keep the flow speeds on the path through the system as constant as possible and not to make them dependent on the particular air flow proportions of hot air and cold air, it is 8 advantageous for the air inlet opening, the air outlet opening and the bypass duct to have at least approximately the same cross-sections.
The air ducts preferably extend at least approximately in the same direction as the portion of the bypass duct extending parallel to the heating heat exchanger. This produces a preferred air flow without a change of direction to the air ducts so that it is not necessary to provide deflecting or guide means. In order to be able to use this preferred air flow for windscreen defrosting, which is important for traffic safety, the outlet connection pieces should be provided on the air ducts for defrosting the windscreen.
To ensure that it is also possible to cool the air which is sucked in by the fan and which has a temperature corresponding to the season and the weather conditions, an evaporator of a cooling system is provided in a manner known per se. It is therefore advantageous to form in the housing a space which adjoins an air outlet of the fan volute and into which an evaporator of the cooling system can be inserted. Such an evaporator is always acted upon by the entire air stream; a bypass going round the evaporator is not provided.
9 Embodiments of the invention are explained in more detail hereinafter with reference to the drawings, in which:
Figure 1 is a longitudinal section through a heating system; Figure 2 is a section along the line II-II in Figure 1; Figure 3 is a section along the line III-III in Figure 1; and Figure 4 is a variant of Figure 1 constructed as an air-conditioning system.
In the longitudinal section, shown in Figure 1, through a heating system, a fan 2 having a radial impeller 3 is arranged in an upper portion of a housing 4. This upper portion of the housing 4 is in the form of a fan volute 1 which is constructed in one piece with the housing 4. The lower portion of the housing 4 is formed by a housing shell 41; this part of the housing could, however, also be formed in one piece with the housing. The housing 4 contains an inner housing 6 which, starting from an initial portion 11 of the fan volute 1, extends in the direction towards the lower shell 41 of the housing 4. A heating heat exchanger 7 is arranged in the inner housing 6 and comprises a heat exchanger system 8, an upper water tank 9 and a lower water tank 10.
With the upper water tank 9, the heating heat exchanger 7 lies in the immediate vicinity of the volute housing 1, or of its initial portion 11. Arranged on the upper water tank 9 are receiving connection pieces 14 for receiving and securing connection tubes 13 through which the heating medium is conveyed to the heating heat exchanger. A space 34 entered by the air stream produced by the fan 2 is formed in the housing 4, the air stream leaving the fan volute 1 being indicated with direction arrows 20. Depending on the installation position of the heating heat exchanger 7, the front end face 11 of the heat exchanger system 8 extends approximately parallel to the direction of the air stream 20 leaving the fan volute 1. An insert 15 for guiding air is provided in the housing 4 for the upper delimitation of the space 34. A further insert 16 is arranged in a curved portion of the lower shell 4#.
A bypass duct 12 is formed between the inner housing 6 and the lower shell 41 and also the housing 4, the wall of the inner housing 6 and the wall of the housing 4 or of the shell 41 extending 11 at least approximately parallel to one another. The bypass duct 12 runs first underneath the lower water tank 10 of the heating heat exchanger 7 and then makes a transition into a curved portion 12" which is, finally, adjoined by a portion 121 which extends approximately parallel to the dischargeside end face 111 of the heating heat exchanger 7.
An air flow control flap 23 which is rotatable about a pivot axis 26 and the flap body 24 of which is formed in a curved manner about the pivot axis 26 is arranged in the curved portion 1211 of the bypass duct 12. By means of the air flow control flap 23, the amount of fresh or cold air flowing through the bypass duct 12 can be adjusted or the bypass duct can be completely closed. In the other end position of the air flow control flap 23, the bypass duct 12 is completely open, the flap body 24 adopting a position in which its contour extends parallel to the wall portions of the curved portion 12". As a result of this measure, it is possible to influence the air flow through the bypass duct 12 in a favourable manner.
In the lower region, which is thus remote from the fan 2, the inner housing 6 has, on the side facing the space 34, an air inlet opening 17 which can be closed by means of a pivotably mounted air flow 12 control flap 18. On the other side of the heating heat exchanger 7, an air outlet opening 21 is provided in the inner housing 6 and is arranged diagonally to the air inlet opening 17, relative to the heating heat exchanger 7. As a result of this offset arrangement of the air inlet opening 17 and of the air outlet opening 21, the heat exchanger system 8 is acted upon in an extremely uniform manner over its end face 11 so that a uniform temperature profile is obtained. Air guide components 22 are arranged in the air outlet opening 21 and are orientated substantially transversely to the portion 121 of the bypass duct 12. These guide components 22 cause the hot air stream leaving the heating heat exchanger 7 to impinge substantially transversely on the cold air stream or fresh air stream guided through the portion 121 and this gives rise to intensive mixing.
Secured to the air flow control flap 18 is a lever 19 to which a rod assembly (not shown in the drawing) or a Bowden cable for operating the flap is articulated. The lever 19 is connected via a rod assembly 27 to a lever 25 of the flap 23 so that the two flaps 18 and 23 are operated simultaneously. The functioning of the flaps 18 and 23 is such that, when the air flow control 13 flap 18 moves in the direction of closing the air inlet opening 17, an opposite movement of the air flow control flap 23, namely in the direction of opening the bypass duct 12, takes place and vice versa.
An outlet connection piece 28 in which a pivotably mounted flap 29 is arranged is provided in the wall of the housing 4. The outlet connection piece 28 is provided for the connection of an air duct leading to discharge nozzles in the dashboard. As shown in Figure 1, the outlet connection piece 28 is arranged diagonally opposite the air outlet opening 21 of the inner housing 6. Air ducts 31 are added as an extension of the portion 121 of the bypass duct 12, only one air duct 31 being shown in the view in Figure 1. The beginning of the air duct 31 has an outlet connection piece 30 which continues at rightangles therefrom and to which an air guide duct for the foot area nozzles can be connected. The air duct 31 extends along the fan volute 1, the upper end of the air duct 31 being in the form of an outlet connection piece 33. This outlet connection piece 33 to which an air guide duct which leads to defroster nozzles underneath the windscreen can be connected extends approximately flush with the extent of the fan volute 1 which is 14 outermost in this direction of the housing 4. stop flap 32 is arranged in the air duct 31 upstream of the outlet connection piece 33.
Figure 2 shows a section along the line II-II in Figure 1. This view clearly shows that the initial region 11 of the fan volute 1 lies between the receiving connection pieces 14, 141 at the upper water tank 9 of the heating heat exchanger 7 and between the connection tubes 13 and 13'. The diffuser-like contour of the fan volute 1 extends as far as the beginning of the straight and parallel-extending wall portions of the housing 4 which is closed at its lower end by the shell 41. The side edges of the heat exchanger system 8 are sealed against the wall of the housing 4 by means of a seal 37 in order to avoid secondary air flowing past near the heat exchanger system. With the lower water tank 10, the heating heat exchanger 7 abuts the inner housing 6 in sealing manner, and the bypass duct 12 is formed between the wall of the inner housing 6 and the lower shell 41 of the housing 4. The fan volute 1 contains the radial impeller 3 which is secured to a shaft 38 of a drive motor 36. A suction connection piece 35 which sucks in fresh air, or ambient air withdrawn from the interior of the is vehicle, is formed on the end face of the volute housing 1 lying opposite the drive motor 36.
Figure 3 shows a section along the line III-III in Figure 1. This view clearly shows the position of the air guide ducts 31, 311 to the side of the portion 11 of the fan volute 1. The flaps 32, 321 by means of which the passage cross-section of the air ducts 31, 311 can be adjusted are arranged in front of the outlet connection pieces 33, 331. Figure 3 also shows that the outlet connection pieces 30, 30' for connecting the air guide ducts for the foot area nozzles are arranged at rightangles to the air ducts 31, 311 and project laterally from the housing 4. Flaps 42, 421 are provided in the outlet connection pieces.
Figure 4 shows a variant of Figure 1 which differs from the previously described embodiment in that the inserts 15 and 16 have been removed from the housing 4 or from the lower shell 41, and an evaporator 39 has been inserted in the space 34. Coolant lines 40 and 41 of a compression cooling system are connected to the evaporator. Thus the system can be designed as a heating system or as an air-conditioning system, as desired, without changing the outer contour of the housing and while retaining nearly all the components. The 16 other reference numerals in Figure 4 are the same as those of the embodiments described above where the parts are the same.
17 CLAIMS 1. Heating or air-conditioning system for a motor vehicle having a fan (2), arranged in a housing (4), and a heating heat exchanger (7), wherein the fan (2) comprises at least one radial impeller (3) running round in a fan volute (1) and the heating heat exchanger (7) is arranged, in the air stream, downstream of the fan (2), and having several outlet connection pieces (28, 30, 301, 33, 331) arranged, downstream of the heating heat exchanger (7), on the housing (4) for the air to be conveyed to the interior of a vehicle, characterised in that the heating heat exchanger (7) is arranged in the housing (4) in such a manner that one of its side limits lies in the immediate vicinity of the fan volute (11) and the end face (11) of the heat exchanger core (8) extends at least approximately parallel to the air stream (20) leaving the fan volute (1), and in that a portion (11) of the fan volute (1) is arranged between connection tubes (13, 131) of the heating heat exchanger (7) and/or between air ducts (31, 311) of the housing (4) which lead to outlet connection pieces (33, 331).
2. System according to Claim 1, characterised in that a bypass duct (12) which can 18 be closed by means of an air flow control flap (23) is formed on the side of the heating heat exchanger (7) that is remote from the fan (2).
3. System according to Claim 2, characterised in that an inner housing (6) having at least one air inlet opening (17) and at least one air outlet opening (21) is provided and the heating heat exchanger (7) is arranged in the inner housing (6).
4. System according to Claim 3, characterised in that the bypass duct (12) is formed between the inner wall of the housing (4) and the outer wall of the housing (6) and at least one portion (121) of the bypass duct (12) extends approximately parallel to the end face (11, 111) of the heat exchanger core (8).
5. System according to Claim 4, characterised in that a curved portion (1211) of approximately 90' is provided upstream of the parallelextending portion (121) of the bypass duct (12).
6. System according to Claim 5, characterised in that the air flow control flap (23) is arranged in the curved portion (1211) and 19 the flap body (24) is formed in a curved manner about its pivot axis (26).
7. System according to any one of Claims 3 to 6, characterised in that a pivotably mounted air flow control flap (18) by means of which the air inlet opening (17) can be closed is provided in the region of the air inlet opening (17).
8. System according to any one of Claims 1 to 7, characterised in that the air inlet opening (17) is arranged in a region of the inner housing (6) remote from the fan (2), and the air outlet opening (21) is arranged in a diagonally offset manner with respect to the air inlet opening (17), relative to the direction of air flow through the heating heat exchanger (7).
9. System according to any one of Claims 3 to 8, characterised in that air guide components (22) by means of which the air is discharged from the inner housing (6) substantially transversely to the air flow direction in the portion (121) of the bypass duct (12) are provided in the air outlet opening (21).
10. System according to Claim 7, characterised in that the air flow control flap (18) in the air inlet opening (17) and the air flow control flap (23) in the bypass duct (12) are connected mechanically in such a manner that an increase in the air flow through the air inlet opening (17) causes a reduction in the air flow through the bypass (12) and vice versa.
11. System according to Claim 3, characterised in that the air inlet opening (17), the air outlet opening (21) and the bypass duct (12) have at least approximately the same crosssections.
12. System according to any one of the preceding claims, characterised in that the heating heat exchanger (7) has, on its side arranged in the immediate vicinity of the fan volute (11), a water tank (9) which is provided with receiving connection pieces (14, 14') which are intended for the connection tubes (13, 131) and which are located to the side of the portion (11) of the fan volute (1).
13. System according to Claim 4, characterised in that the air ducts (31, 31') extend at least approximately in the same direction as the portion (121) of the bypass duct (12).
21 14. System according to Claim 13, characterised in that the outlet connection pieces (33, 331) are provided on the air ducts (31, 311) for defrosting the windscreen and can be closed by means of flaps (32, 321).
15. System according to any one of the preceding claims, characterised in that a space (34) which adjoins an air outlet of the fan volute (1) and into which an evaporator (39) of a cooling system can be inserted is formed in the housing (4).
16. Air conditioning system for a motor vehicle substantially as described herein with reference to the accompanying drawings.
17. Heating system for a motor vehicle substantially as described herein with reference to the accompanying drawings.