FAN WHEEL OF A MOTOR VEHICLE

Abstract

A fan wheel and a radiator of a motor vehicle, the fan wheel having a hub to which a number of fan blades is connected. The fan blades each have a stabilizing structure of a first material, which is surrounded by means of a respective body of a second material.

Claims

1. A fan wheel of a motor vehicle, the fan wheel comprising: a hub to which at least two fan blades is connected; and a stabilizing structure formed on each of the at least two fan blades, the stabilizing structure comprising a first material surrounded by a respective body of a second material.

2. The fan wheel according to claim 1, wherein the bodies of the second material are formed by overmolding the stabilizing structure.

3. The fan wheel according to claim 1, wherein the hub and the body are one-piece.

4. The fan wheel according to claim 1, wherein each stabilizing structure has at least two at least partially radially extending struts.

5. The fan wheel according to claim 4, wherein the extension of the struts is increased in the axial direction.

6. The fan wheel according to claim 1, wherein the fan blades are connected at their radial outer end to an outer ring arranged concentrically to the hub.

7. The fan wheel according to claim 6, wherein the outer ring has a further stabilizing structure of another first material, which is surrounded by another body of another second material.

8. The fan wheel according to claim 7, wherein the stabilizing structures and the further stabilizing structure are directly attached to each other.

9. The fan wheel according to claim 7, wherein the further stabilizing structure is a hollow cylinder arranged concentric to the hub.

10. A radiator fan of a motor vehicle, the radiator fan, comprising: a wheel according to claim 1; and a fan frame that has a round recess within which the fan wheel is arranged and which is driven by an electric motor that is connectable to the fan frame.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0032] FIG. 1 schematically shows a land-based motor vehicle with a radiator fan,

[0033] FIG. 2 schematically shows simplified in an exploded view, partially the radiator fan with a fan wheel,

[0034] FIG. 3 shows in perspective, the fan wheel having a plurality of fan blades,

[0035] FIG. 4 shows in part an end region of one of the fan blades, and

[0036] FIGS. 5 and 6 show in each case, in perspective, a variant of the fan wheel.

DETAILED DESCRIPTION

[0037] FIG. 1 shows a schematically simplified motor vehicle 2 in the form of a passenger car, having an internal combustion engine 4. The motor vehicle 2 is driven by means of the combustion engine 4. For this purpose, the combustion engine 4, by means of an unspecified drive train, is in active connection with at least one of the four wheels 6 of the motor vehicle 2. In addition, the motor vehicle 2 comprises a radiator fan 8, which serves to cool the combustion engine 4. Thus, the radiator fan 8 is a main fan of the motor vehicle 2. The radiator fan 8 is fluidically connected to the combustion engine 4 by means of a number of lines 10, through which a coolant is led during operation from the radiator fan 8 to the combustion engine 4 and through cooling channels therein. By means of the coolant, excess heat is absorbed and led back to the radiator fan 8, by means of which a cooling of the coolant takes place.

[0038] The radiator fan 8 comprises a radiator 12 with a radiator network, not further shown, through which a number of pipes are passed and are thermally contacted with it. The pipes are fluidically coupled with the lines 10, so that during operation, the coolant is passed through the pipes. The radiator fan 8 further comprises a fan frame 14, which is arranged in a direction of travel 16 of the motor vehicle 2 behind the radiator 12. An electric motor 18 is attached to the fan frame 14. During operation, an air stream passes through the radiator 12 and is suitably shaped by means of the fan frame 14. When the motor vehicle 2 is stopped, air is sucked through the radiator 12 by means of the electric motor 18, so that the radiator 12 is essentially always, or at least depending on existing requirements, interspersed with the air stream during operation. Thus, a cooling of the radiator 12 takes place, which is why even after a comparatively long operation of the combustion engine 4 no overheating of the radiator fan 8 takes place. In addition, by means of the fan frame 14, the air passing through the radiator fan 8 is directed to the combustion engine 4 and the latter is additionally cooled in this way from the outside.

[0039] FIG. 2 shows the radiator fan 8 schematically simplified, in perspective in an exploded view, wherein the radiator 12 is omitted. On the radiator 12, the fan frame 14 is attached, which completely covers the radiator network, not shown, and is congruent with this. The fan frame 14 is essentially flat and has a round recess 20, which is oriented perpendicular to the direction of travel 16, and which has a diameter of 30 cm.

[0040] The fan frame 14 further comprises a motor mount 22, which is arranged counter the direction of travel 16 above the recess 20 and held there by means of a plurality of mounting struts 24. In the assembly state, the electric motor 18 is held by means of the motor mount 22 and the electric motor 18 thus attached to this. Here, the electric motor 18 is located on the opposite side of the radiator 12 of the fan frame 14. A shaft 26 of the electric motor 18 protrudes in the direction of travel 16 through the motor mount 22 and is attached in a rotationally fixed manner to a hub 28 of a fan wheel 30. Thus, the fan wheel 30 is driven by means of the electric motor 18, which is held by means of the motor mount 22. At the hub 26, a number of fan blades 32 is connected.

[0041] In the assembly state, the fan wheel 30 is arranged parallel to the recess 20 within this and is rotated during operation by means of the electric motor 18 about an axis of rotation 34, which is parallel to the direction of travel 16, and which extends through the center of the recess 20. Thus, air is sucked through the recess 20 counter the direction of travel 16 during operation.

[0042] In addition, the fan frame 14 comprises a dynamic pressure damper 36, which comprises an opening which is covered by a flap 38. If there is a comparatively high (air) pressure in the direction of travel 16 in front of the fan frame 14, in particular with a comparatively fast movement of the motor vehicle 2, the passage of air through the recess 20 is partially hindered due to the fan wheel 30 or the fan wheel 28 30 can be rotated comparatively quickly. However, this would lead to an increased load on the electric motor 18 and the other component and to increased noise. From a certain pressure, the flap 38 is therefore swiveled and the opening released so that air can flow through it. Thus, an air stream through the radiator 12, which is located in the direction of travel 16 in front of the fan frame 14, is increased. At a comparatively low air pressure in front of the fan frame 14, as is the case with a standstill of the motor vehicle 2, the flap 38 is closed, so that the formation of a circular air stream passing only through the opening of the dynamic pressure damper 36 and the recess 20 is prevented. Thus, the radiator 12 is always interspersed by means of a sufficient air stream.

[0043] FIG. 3 and FIG. 4 show, enlarged in sections in perspective in a semi-transparent representation, the fan wheel 30 which is rotationally symmetrical with respect to the axis of rotation 34. The fan wheel 34 comprises the pot-shaped hub 28, to which in this example a total of nine fan blades 32 are connected, which run partly radially and partly tangential with respect to the axis of rotation 34. In other words, the fan blades have a crescent shape, wherein these constantly face the same direction in the tangential direction. To create the air stream through the fan frame 14, the fan blades 32 are inclined slightly perpendicular to a plane perpendicular to the axis of rotation 34. The radial ends of the fan blades 32 with respect to the axis of rotation 34 are bluntly designed in this embodiment, and the fan wheel 30 is thus without an outer ring.

[0044] Each of the fan blades 32 comprises a stabilizing structure 40, which is formed by means of three spaced struts 42. The struts 42, and thus the respective stabilizing structure 40, is made of a first material, namely a steel. As a result, the struts 42 have a comparatively high stability, but the weight is increased. The struts 42 are identical to each other or at least built from the same by means of cutting to length and suitable bending so that all struts 42 have the same cross-section over their complete course.

[0045] Here, the course of the struts 42 is substantially equal to the course of the respective fan blade 32, wherein the radial outer ends of the struts 42 of the respective stabilizing structure 40 are offset to each other, so that do not have a completely parallel course. The struts 42 extend in this embodiment from the radial outer end of the respective fan blade 32 to the hub 28. In a variant, not shown, the struts 42 are shortened so that they are radially offset outwards from the hub 28. The struts 42 have a substantially rectangular cross-section perpendicular to their course. Here, their extension is increased in the axial direction, i.e., parallel to the axis of rotation 34. In this way, the stability of struts 42 in this direction is increased.

[0046] Each of the fan blades 32 further comprises a body 44 which is made of a second material, namely a plastic, by overmolding the respective stabilizing structure 40. Thus, the second material differs from the first material. Each body 44 is also arranged between the individual struts 42 of the same fan blade 32, and these are held captively by means of the respective body 44. By means of the respective body 44, the external shape of the respective fan blade 32 is predetermined, and the struts 42, and consequently also each stabilizing structure 40, are completely surrounded by the respective body 44, except for their respective ends.

[0047] The bodies 44 are made of the second material, namely a polyamide, wherein the hub is also made of the second material. The hub 28 and the body 44 are one-piece, so that a separate attachment of the fan blades 32 to the hub 28 is not required. Robustness is also increased in this way. For the production of the fan wheel 30, the stabilizing structures 40 are suitably positioned within a mold, which is subsequently filled by means of the second material by injection molding, so that all cavities of the mold are filled. As a result, the bodies 44 and the hub 28 are created, wherein the stabilizing structures 40 are surrounded by the respective bodies 44.

[0048] FIG. 5 shows an alternative embodiment of the fan wheel 30, wherein the hub 28 and the fan blades 32 are not changed. However, the fan blades 32 are surrounded by an outer ring 46 arranged vertically and concentrically to the axis of rotation 34. Thus, the outer ring 46 is also concentric to the hub 28, and these are essentially arranged in a common plane which is perpendicular to the axis of rotation 34. The radial outer ends of the fan blades 32 are attached to the outer ring 46. The outer ring 46 is created one-piece from the second material and formed on the bodies 44. In production, the outer ring 46 is created in one step with the hub 28 and the bodies 44 by injection molding.

[0049] The outer ring 46 has an essentially L-shaped cross-section, which thus comprises two legs. In this case, one of the legs is arranged parallel to the axis of rotation 34, and the remaining one points radially outwards from this. In this way, stability is increased, wherein the weight of the fan wheel 30 is not excessively increased. In the assembly state, an unspecified contour arranged on the radially outwardly projecting leg engages in a corresponding contour of the fan frame 14, which surrounds the recess 20, so that a labyrinth seal is created. In this way, leakage air between the fan wheel 30 and the fan frame 14 is minimized.

[0050] FIG. 6 shows a further modification of the fan wheel 30. The hub 28 is not changed. Also, the outer ring 46 is again present. However, this is no longer merely designed in one piece, but has a further stabilizing structure 48, which is formed by means of a hollow cylinder made of a further first material and arranged concentrically to the hub 28 and thus also to the axis of rotation 34. The other first material is equal to the first material and thus a steel.

[0051] Compared to the preceding embodiment, in the fan blades 32, the struts 42 are slightly extended at their radial outer end, and welded to the further stabilizing structure 48, i.e., the hollow cylinder. Thus, the stabilizing structures 40 and the further stabilizing structure 48 are directly attached to each other.

[0052] The further stabilizing structure 48 of the outer ring 46 is surrounded by another body 50 from the further second material. By means of the further body 50, the outer shape of the outer ring 46 is specified, which corresponds to the outer shape of the preceding embodiment. The further second material is the same as the second material, and the further body 50 is formed in one piece with the respective bodies 44.

[0053] To produce this fan wheel 30, the further stabilizing structure 48, to which the stabilizing structures 40 are already attached, is inserted into a corresponding mold, which is subsequently filled by means of the second material, which also forms the further second material, so that the stabilizing structures 40 and the further stabilizing structure 48 are overmolded by means of the second material and thus surrounded. The hub 28 is also created. Due to the further stabilizing structure 48, the positioning of the stabilizing structures 40 within the mold is facilitated.

[0054] The invention is not limited to the embodiments described above. Rather, other variants of the invention can be derived from it by the skilled person without departing from the subject-matter of the invention. In particular, all the individual features described in connection with the individual embodiments can also be combined in other ways without departing from the subject-matter of the invention.

[0055] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.