Fan wheel for motor vehicle

Abstract

The invention relates to a fan wheel for a motor vehicle, comprising a hub (24) to which a plurality of sickle-shaped fan blades (30) are connected, each of which has a front edge (36) and a rear edge (38), and the front edge and the rear edge are connected on the end side to an outer ring (32). A first angle (40) is formed between the leading edge (36) and the outer ring (32) and a second angle (48) is formed between the trailing edge (38) and the outer ring (32), and wherein both angles are greater than 90 DEG. The invention also relates to a radiator fan (8) for a motor vehicle (2).

Description

TECHNICAL FIELD

[0001] The invention relates to a fan wheel for a motor vehicle, the fan wheel having a hub, to which a plurality of fan blades are attached. The fan wheel is preferably part of a radiator fan of a motor vehicle. The invention also relates to a radiator fan, for example a main fan, for a motor vehicle. BACKGROUND

[0002] Motor vehicles having an internal combustion engine generate a large amount of heat during operation, so that the internal combustion engine has to be cooled. If the motor vehicle has an electric motor for propulsion, a high-voltage energy store is charged and discharged during operation, wherein losses also occur here, so that the high-voltage energy store has to be cooled. In order to cool and also in order to operate air conditioning systems, a liquid coolant / refrigerant is usually used, which is heated as a result. In order to cool the coolant / refrigerant again, a radiator grid, which is loaded by the driving wind, is usually used, which is in heat exchange with the coolant / refrigerant. For this purpose, for example, the coolant / refrigerant is guided into a tube, which is integrated into the radiator grid. Since the driving wind is usually not sufficient for cooling, in particular at low vehicle speeds, it is known to use an electric fan, by means of which the driving wind is intensified or generated accordingly.

[0003] The fan is usually arranged behind the radiator grid in the driving direction. Air is then sucked by means of the fan wheel of the fan in order to pass through the radiator grid and, if necessary, to be guided onto the internal combustion engine. There, the air absorbs the excess heat of the internal combustion engine and carries it away.

[0004] In order to achieve a relatively high air volume throughput through the radiator grid, it is possible to rotate the fan wheel at a relatively high rotational speed. However, it is possible here that, on the one hand, the air flow is interrupted. On the other hand, a relatively high-frequency vibration will occur in this way, which can be perceived as unpleasant. Instead of this, it is possible to select the fan wheel diameter to be relatively large, which, however, leads to an increased space requirement.

[0005] In the above-described solutions, a higher force consumption is also required in order to rotate the fan wheel. As a result, a relatively powerful electric motor is required, which leads to an increased production cost. As an alternative, it is therefore provided that the fan blades are sickle-shaped, so that the fan blades have a curved shape. As a result, the length of the fan blades is increased, wherein, however, the radius of the fan wheel itself is not increased. It is therefore also possible to rotate the fan wheel with a reduced torque. Here, the fan blades are sickle-shaped, for example, only in the forward direction or in the reverse direction, which leads to different advantages and disadvantages. SUMMARY

[0006] The objective of this invention is to provide a fan wheel particularly suitable for motor vehicles and a radiator fan particularly suitable for motor vehicles, wherein, in particular, performance and / or stability are improved, and wherein, acoustic improvements are suitably achieved.

[0007] According to the invention, the task concerning the fan wheel is solved by the feature of claim 1, and the task concerning the radiator fan is solved by the feature of claim 9. Advantageous improvements and designs are the subject of the corresponding dependent claims.

[0008] In its installed state, the fan wheel is preferably an integral part of the motor vehicle and is suitably configured and set up for this purpose. In particular, the fan wheel, in its installed state, is an integral part of the motor vehicle's radiator fan. Here, the fan wheel is suitably, and especially, configured and set up for drawing in or blowing air through the motor vehicle's radiator. The radiator fan, and thus the fan wheel, is preferably used to cool the internal combustion engine or high-voltage energy storage device, such as the motor vehicle's high-voltage battery. Suitablely, the coolant / refrigerant is cooled by means of the radiator, and / or the airflow is directed to the possible internal combustion engine by means of the fan wheel. Alternatively, the fan wheel may be, for example, an integral part of a blower, by means of which air is delivered, in particular, to the interior space of the motor vehicle. The motor vehicle is suitably land-based and, for example, a passenger vehicle (Pkw). Alternatively, the motor vehicle may be a commercial vehicle, such as a truck (Lkw) or a bus.

[0009] The fan impeller has a generally planar design. However, at least, the extension of the fan impeller in one plane is greater than its extension perpendicular to that plane. The fan impeller is suitable, and especially is configured and arranged for rotation about an axis of rotation. In particular, the axis of rotation is perpendicular to the plane in which the fan impeller is located. The fan impeller is preferably an axial-flow fan impeller. Thus, during operation, air moves along the axis of rotation by means of the fan impeller. The diameter of the fan impeller is suitably between 30 cm and 60 cm, between 40 cm and 50 cm, for example, substantially equal to 48 cm, wherein deviations of 5 cm, 2 cm, or 0 cm are suitably present, respectively.

[0010] The fan wheel itself has a hub on which multiple fan blades are attached. The hub is suitable, and particularly preferably, configured for fastening to an electric motor. In the installed state, a possible electric motor is suitably fastened to the hub, and the fan wheel rotates about a rotation axis by means of the electric motor. Here, the hub is suitably arranged concentrically with the rotation axis, which reduces imbalance and thus reduces unwanted noise generation and overload. Preferably, the hub is designed to be substantially can-shaped, wherein the bottom of the can is suitably arranged substantially perpendicular to the rotation axis. The fan blades are suitably attached to the outer circumferential surface of the can-shaped hub wall. Suitably, if the hub is designed to be can-shaped, the can opening is open against the possible airflow, especially against the direction of travel wind and / or the direction of movement of the vehicle. Thus, air resistance is reduced. Alternatively, the can opening is open towards the possible airflow. Suitably, the outer side of the hub is designed to be substantially smooth.

[0011] The fan blades (also referred to in particular as fan wheel blades) are preferably identical in structure, which simplifies manufacturing and installation. Each fan blade has a leading edge and a trailing edge, which are defined, in particular, based on the predetermined direction of rotation of the fan wheel. The fan blades are tilted / offset about the axis of rotation, for example. Thus, each fan blade has a main extension direction tilted about the axis of rotation. Consequently, the leading edge of each fan blade is offset about the trailing edge parallel to the axis of rotation (i.e., in the axial direction). This offset angle is particularly formed between 10° and 40° or between 15° and 30°. Based on this tilt, the movement of air in the axial direction (i.e., along or at least parallel to the axis of rotation) is achieved by means of the fan wheel during operation.

[0012] Each fan blade has at least partially, and particularly with respect to the axis of rotation, a substantially radial orientation, such that the fan blade points outward from the hub. Here, the fan blades are designed to be curved, thereby suitably forming a sickle shape. In other words, the fan blades are sickle-shaped. Consequently, the radially outer ends of each fan blade are offset tangentially with respect to the radially inner ends with respect to the axis of rotation. Suitable here, the directions of offset of all radially outer ends of the fan blades are the same.

[0013] The fan blades are attached to the outer ring at their end sides (i.e., particularly at the radially outer ends). Thus, the fan blades extend between the hub and the outer ring. The outer ring is suitably concentric with, or at least preferably with, the possible axis of rotation of the hub. In particular, the hub is surrounded by the outer ring at a distance on its peripheral side. The fan blades are stabilized with each other by means of the outer ring. Preferably, the outer ring includes, for example, a contour on its outer side that, in the installed state, embeds itself into other components of the vehicle, thereby forming a labyrinthine seal. This prevents air leakage.

[0014] A first angle is formed between the leading edge and the outer ring. Therefore, in the region where each fan blade contacts the outer ring, the leading edge has a direction that is skewed by the first angle with respect to the tangential direction there. A second angle is formed between the trailing edge and the outer ring. In other words, the trailing edge has a second angle with respect to the tangential direction there in the region where it contacts the outer ring.

[0015] Both the first and second angles are greater than 90°. Therefore, the leading and trailing edges of each fan blade engage with the outer ring at obtuse angles. In other words, no acute angles are formed in the areas where the two edges engage with the outer ring. This results in a relatively large engagement surface between each fan blade and the outer ring, leading to a stable connection and improved robustness. Furthermore, it simplifies demolding, thus simplifying manufacturing. Additionally, the increased area of ​​the fan blades within the outer ring area allows for an increase in the amount of air transported during operation via the fan wheel, without requiring an increase in the fan wheel's rotational speed or diameter. This, in turn, improves performance. Here, based on the relatively stable connection and increased area, unwanted vibrations are avoided, thus improving acoustics.

[0016] For example, different fan blades are assigned different first and second angles, both of which are greater than 90°. However, it is particularly preferred that all first and all second angles are equal. For example, the fan wheel is designed to be rotationally symmetrical. This simplifies manufacturing and structure. Furthermore, it eliminates or simplifies the orientation with other components of the vehicle, making installation easy. Alternatively, the angles formed between adjacent fan blades are different. This allows for proper shaping of the airflow. For example, the fan wheel is composed of different components. However, it is particularly preferred that the fan wheel is a single piece. Suitablely, the fan wheel is made of plastic, preferably by injection molding. This reduces manufacturing costs.

[0017] The fan blades are, for example, sickle-shaped to the rear. Therefore, the radially outer ends of the fan blades are offset relative to the radially inner regions against the direction of rotation of the fan wheel. However, it is particularly preferred that the fan blades are sickle-shaped to the front. Therefore, the radially outer ends of the fan blades are offset forward in the direction of rotation of the fan wheel. This prevents the formation of undesirable air vortices and thus improves acoustics.

[0018] For example, the rear edge and the hub are perpendicular to each other in the area of ​​contact. Alternatively or in combination with this, a 90° angle is formed between the front edge and the hub in the area of ​​contact, so that the edges extend from the hub at right angles. Alternatively, this angle is greater than 90°. However, it is particularly preferred that a smaller angle is formed between the rear edge and the hub, particularly less than 70° and preferably less than 60°. Suitably, this angle is greater than 30°, 40° or 50°. Suitablely, the angle is substantially 55° or 45°. Thus, although it is an acute angle, a relatively stable contact is still achieved and manufacturing does not become difficult. Alternatively or particularly preferably in combination with this, an angle greater than 100° is formed between each front edge and the hub, wherein this angle is preferably less than 130° and 120°. Thus, based on this choice of angle, each fan blade extends substantially at least partially against the direction of rotation in the area extending from the hub. Therefore, by combining the forward-snake shape, relatively large lengths are achieved for both the front and rear edges, thereby increasing the effective length of the fan blades. This results in a larger airflow being transported, thus improving fluid efficiency. In an alternative, the angle formed between each front edge and the hub is less than 90°.

[0019] Preferably, the first angle is greater than 110° and particularly less than 180°. Preferably, the first angle is greater than 130° and particularly between 150° and 160°. Suitably, the first angle is essentially 155°. Thus, a relatively stable mating surface exists on the outer ring, wherein the arc length required for this on the outer ring is not excessively increased.

[0020] Alternatively or particularly preferably, in conjunction with this, the second angle is between 120° and 170°. Suitably, the second angle is greater than 135° and particularly preferably between 140° and 160°. In particular, the second angle is essentially 145° or 155°. Thus, a relatively stable mating surface also exists on the outer ring, wherein the arc length required for this on the outer ring is not excessively increased.

[0021] For example, the first and second angles of the respective fan blades are different from each other. However, it is particularly preferred that they are equal to each other. Suitablely, these two angles are between 150° and 160°. In particular, the first and second angles are essentially both equal to 155°. This results in symmetry, which leads to improvements in acoustics and increased stability.

[0022] For example, the front edge is designed to be wavy. However, it is particularly preferred that the front edge is unidirectionally arched, and thus only arched to the left or right. In other words, the front edge is designed to be substantially U-shaped or C-shaped. Therefore, the second derivative of the front edge changes without a sign. Based on this implementation, manufacturing is easier and stability is improved.

[0023] Appropriately, the arching behavior of the rear edge changes at the inflection point. Thus, the rear edge arches not only to the left but also to the right. For example, here the rear edge is designed to be wavy. However, it is particularly preferred that the rear edge be S-shaped, so that the rear edge has only one inflection point where the bending behavior changes. This simplifies manufacturing and avoids the formation of undesirable air vortices.

[0024] For example, the distance between the inflection point and the hub is essentially equal to half the distance between the hub and the outer ring, that is, specifically half the radial distance between the outer diameter of the hub and the inner diameter of the outer ring. Alternatively, this distance may be smaller or preferably larger. However, suitably, the distance between the inflection point and the hub is between 80% and 90% of the distance between the outer ring and the hub. Thus, the arching behavior of the rear edge reverses between 80% and 90% of the distance, and suitably at 85%. The outer third of each fan blade has a significant impact on the fluid efficiency of the fan impeller. Based on the choice of inflection point positioning, the rear edge arches both forward and backward in this significant region, wherein the individual fan blades are particularly sickle-shaped forward based on the design of the front edge. Thus, the advantages of both the forward and backward sickle shapes are utilized in this fan impeller, which also simplifies the design structure. It also makes demolding from the mold easier.

[0025] Preferably, at 75% of the distance between the outer ring and the hub, the leading edge forms an angle between 100° and 110° relative to the tangential direction, particularly 105°. The trailing edge, especially in this region, has an angle between 50° and 60°. Thus, the two edges are at least approximately parallel, so the width of the fan blades does not vary excessively.

[0026] In its installed state, the radiator fan is suitably an integral part of the motor vehicle and is therefore suitable and preferably configured for installation on other components of the motor vehicle. The radiator fan is suitably used for cooling the internal combustion engine. In other words, the radiator fan is the main fan. Alternatively, the radiator fan may be, for example, a component of the motor vehicle's air conditioning system or auxiliary unit. The radiator fan suitably includes a radiator, particularly having a radiator mesh, preferably through which multiple pipes are guided. Here, the radiator mesh, for example, is in thermal contact with the pipes. Coolant / refrigerant, such as coolant fluid, is preferably guided inside the pipes during operation. The radiator mesh, for example, is designed to be substantially rectangular.

[0027] In addition, the radiator fan also includes a fan shroud with a circular opening. A fan wheel with a hub is suitably arranged parallel to the circular opening and / or the fan shroud within the circular opening, and a plurality of sickle-shaped fan blades are attached to the hub. Each fan blade has a leading edge and a trailing edge and is attached to an outer ring at its end. Here, a first angle is formed between each leading edge and the outer ring, and a second angle is formed between each trailing edge and the outer ring. Both the first and second angles are greater than 90°. Preferably, the fan wheel and the opening are arranged concentrically.

[0028] In addition, the radiator fan also includes an electric motor, such as a brushed commutator motor or preferably a brushless direct current motor (BLDC). The electric motor is fastened to the fan shroud. For example, the fan shroud includes a motor holder, which is held above the open section by means of multiple mounting supports. Here, the rotation axis of the electric motor is arranged perpendicular to the open section, and in particular extends along the rotation axis of the fan wheel, preferably along a straight line passing through the center point of the open section. For example, the electric motor is bonded or screwed to the motor holder. Thus, the electric motor is held relatively securely on the motor holder. The fan wheel is driven by the electric motor and is preferably connected to the electric motor, for example, connected to the shaft of the electric motor. The hub is, for example, directly mechanically coupled to the electric motor.

[0029] In particular, the outer rings are embedded in corresponding receiving portions or contours of the fan shroud, wherein they are preferably spaced apart from each other. Specifically, a labyrinthine seal is formed between them, thus preventing the diffusion of leaked air. Alternatively or in combination with this, a brush seal, rib structure, or similar structure is arranged between the outer rings and the fan shroud.

[0030] The fan shroud is preferably attached to the radiator, preferably fastened. The fan shroud is screwed onto or glued to the radiator, for example. Alternatively, they snap together, lock together, or the fan shroud is suspended from the radiator. In particular, the fan shroud covers, if possible, the radiator grille. In other words, the fan shroud completely overlaps with the radiator grille or, for example, the entire radiator. This prevents air from flowing between the radiator and the fan shroud, and thus achieves relatively effective airflow guidance by means of the fan shroud. The fan shroud is preferably positioned downstream of the radiator, i.e., suitably behind the radiator in the direction of travel of the vehicle.

[0031] The advantages and improvements described for the fan wheel also apply to the radiator fan, and vice versa. Attached Figure Description

[0032] The embodiments of the present invention are further described below with reference to the accompanying drawings. In the drawings:

[0033] Figure 1 The illustration schematically depicts a motor vehicle equipped with a radiator fan.

[0034] Figure 2 A radiator fan with a fan wheel and multiple fan blades is schematically and simplifiedly shown in part in the form of an exploded view.

[0035] Figure 3 The fan wheel is shown in a top-down view.

[0036] Figure 4 The end region of one of the fan blades is shown in a truncated form.

[0037] Corresponding parts are labeled with the same reference numerals in all the accompanying drawings. Detailed Implementation

[0038] Figure 1 The diagram schematically simplifies the representation of a motor vehicle 2, which is a passenger vehicle (Pkw) and has an internal combustion engine 4. The internal combustion engine 4 drives the motor vehicle 2. For this purpose, the internal combustion engine 4 is operatively connected to at least one of the four wheels 6 of the motor vehicle 2 via a drive system (not shown in detail). Furthermore, the motor vehicle 2 includes a radiator fan 8 for cooling the internal combustion engine 4. Thus, the radiator fan 8 is the main fan of the motor vehicle 2. The radiator fan 8 is fluidically connected to the internal combustion engine 4 via multiple lines 10, through which coolant flows from the radiator fan 8 to the internal combustion engine 4 during operation and is guided through cooling channels therein. Excess heat is absorbed by the coolant and returned to the radiator fan 8, thereby achieving cooling of the coolant.

[0039] The radiator fan 8 has a radiator 12 with a radiator mesh (not shown in detail), through which multiple pipes are guided and in thermal contact with the radiator mesh. These pipes are fluid-technically coupled to wiring 10, thereby guiding coolant through the pipes during operation. The radiator fan 8 also includes a fan shroud 14, which is arranged behind the radiator 12 in the direction of travel of the vehicle 2. An electric motor 16, designed as a brushless direct current motor (BLDC), is fastened to the fan shroud 14. During operation, the airflow passes through the radiator 12 and is appropriately shaped by the fan shroud 14. When the vehicle 2 is stationary, air is drawn through the radiator 12 by the electric motor 16, thereby ensuring that the radiator 12 is substantially always, or at least dependent on existing demand, under airflow conditions during operation. This achieves cooling of the radiator 12, thus preventing overheating even after the internal combustion engine 4 has been running for a relatively long period. Furthermore, the fan shroud 14 allows air passing through the radiator fan 8 to be directed to the internal combustion engine 4, thereby additionally cooling the internal combustion engine from the outside.

[0040] Figure 2An exploded view of the radiator fan 8 is shown in a simplified, schematic three-dimensional representation, in which the radiator 12 is omitted. A fan shroud 14 is fastened to the radiator 12, completely covering and overlapping the radiator mesh (not shown in detail). The fan shroud 14 is designed to be substantially horizontal and has a circular opening 18 oriented perpendicular to the direction of travel 16 and having a diameter of 50 cm.

[0041] The fan shroud 14 also includes a motor retainer 20, which is arranged above the clearance 18 in the opposite direction of travel and is held there by means of a plurality of mounting supports 22. In the installed state, the electric motor 16 is held by means of the motor retainer 20, and thus the electric motor 16 is fastened to the motor retainer. Here, the electric motor 16 is located on the side of the fan shroud 14 opposite to the radiator 12. The shaft of the electric motor 16 extends through the motor retainer 20 in the travel direction and is fastened to the hub 24 of the fan wheel 26 against relative rotation. Thus, the fan wheel 26 is driven by the electric motor 16, which is held by means of the motor retainer 20.

[0042] Hub 24 is designed to be substantially can-shaped and concentrically arranged with rotation axis 28, on which the shaft of motor 16 is also located, and which is predetermined by means of the shaft of electric motor 16. Here, the can-bottom of hub 24 is arranged perpendicular to rotation axis 28, which also extends through the center point of the recess 18. Radially outward extending sickle-shaped fan blades 30 are attached to hub 24. Thus, fan blades 30 have not only a purely radial orientation with respect to rotation axis 28, but also a tangential orientation. At the radially outward ends, fan blades 30 are fastened to outer ring 32, which is designed to be substantially hollow cylindrical or circular. Here, outer ring 32 surrounds hub 24 at a distance predetermined based on the fan blades 30, which are structurally identical to each other. Here, outer ring 32 is also concentrically arranged with rotation axis 28. The complete fan wheel 26 is designed as an injection-molded part. The various components are constructed such that fan wheel 26 is rotationally symmetrical with respect to rotation axis 28.

[0043] In the installed state, the fan wheel 26 is arranged parallel to the clearance 18 within the clearance 18, and rotates around the rotation axis 28 by means of the electric motor 16 during operation. This rotation axis is parallel to the travel direction 16 and passes through the center point of the clearance 20. Therefore, during operation, air is drawn through the clearance 18 against the travel direction. Here, the outer ring 32 is embedded in the corresponding contour of the fan cover 14, thereby forming a labyrinth seal. Thus, airflow between the fan wheel 26 and the fan cover 14 is prevented. Based on the sickle shape of the fan blades 30, their radially outer ends are offset relative to their radially inner ends in the rotation direction 35. However, at least a portion of each fan blade is offset relative to its radially outer end against the rotation direction 35. Therefore, the fan blades 30 are forward-facing sickle-shaped.

[0044] Furthermore, the fan shroud 14 also includes a dynamic pressure flap 34, which includes an opening covered by the flap. If there is a relatively high (air) pressure in front of the fan shroud 14 in the direction of travel, especially when the vehicle 2 is moving relatively fast, the airflow through the vent 18 is partially obstructed due to the fan wheel 26, or the fan wheel 26 must rotate relatively quickly. However, this leads to increased load on the electric motor 16 and other components, as well as increased noise generation. Therefore, from a certain pressure, the flap pivots and releases the opening, allowing air to flow through it. This increases the amount of air passing through the radiator 12 located in front of the fan shroud 14 in the direction of travel. When the air pressure in front of the fan shroud 14 is relatively low, such as when the vehicle 2 is stationary, the flap closes, preventing the airflow that would otherwise only pass through the opening of the dynamic pressure flap 34 and the vent 18 from circulating. Thus, the radiator 12 is always ensured to be traversed by sufficient airflow.

[0045] Figure 3 The fan wheel 26 is shown in a top view, i.e., a section along the direction of the rotation axis 28, in which only one of the fan blades 30, which are structurally identical to each other, is shown. Figure 4 The end region of the fan blades 30 is also shown in a top view. Each fan blade 30 has a leading edge 36 and a trailing edge 38. Here, as the fan wheel 26 rotates, the trailing edge 38 moves toward the leading edge 36 of the same fan blade 30. In order to generate airflow by means of the fan wheel 26, the leading edge 36 is offset in the axial direction relative to the trailing edge 38, that is, offset parallel to the axis of rotation 28.

[0046] The front edge 36 is substantially C-shaped and thus unidirectionally arched. Here, the curvature increases with increasing radial distance from the axis of rotation 28, wherein the numerical value of the curvature changes, but its sign remains unchanged. Here, a first angle 40 is formed between the front edge 36 and the substantially tangentially extending outer ring 32. The first angle 40 is between 150° and 160°, i.e., 156°. In the region away from the hub 24, there is another angle 42 greater than 100°, for example, 105° or 110°, between the tangential direction and the front edge 36. Therefore, based on this design, each front edge 36 extends against the direction of rotation 35 from its end facing the hub 24, and then, based on the unidirectional arching, extends in the direction of rotation 35 until it reaches the outer ring 32, where the first angle 40 is formed. Here, the change from the direction opposite to the rotation direction 35 to the direction with the rotation direction 35 occurs at a certain distance from the hub 24 (this distance is 70% of the distance between the outer ring and the hub 24).

[0047] The trailing edges 38 do not exhibit unidirectional arching behavior. Therefore, these trailing edges depart from the hub 24 at an angle 44 less than 60°, causing the trailing edges 38 to extend against the rotational direction 35. As the distance from the hub 24 increases, the trailing edges 38 extend along the rotational direction 35 based on curvature until they reach an inflection point 46. There, the arching behavior reverses, and the trailing edges 38 again extend against the rotational direction 35 until they meet the outer ring 32 at a second angle 48. The second angle 48 is equal to the first angle 40, thus the second angle is between 150° and 160° and is 156°. Here, all angles 40, 42, 44, and 48 are known in that they lie outside the various components of the fan wheel 26, and thus depict the orientation of their respective edges or similar components outside the material of the fan wheel 26.

[0048] In summary, the rear edge 38 and hub 24 thus form an angle 44 of less than 60°, for example, 45°. Conversely, the front edge 36 and hub 24 form an angle 42 of greater than 100°, for example, 105°, in the transition region. A first angle 40 of 156°, greater than 90°, is formed between the front edge 36 and the outer ring 32. A second angle 48 of 156°, and therefore also greater than 90°, is formed between the rear edge 38 and the outer ring 32. In an alternative, the second angle 48 is equal to 145°.

[0049] Here, the distance between the inflection point 46 and the hub 24 is 85% of the distance between the outer ring 32 and the hub 24. Therefore, the inflection point 46 is relatively far outward in the radial direction, causing the trailing edge 38 to extend not only against but also with the rotation direction 35 in the region related to fluid efficiency. This results in an advantage: improved fluid efficiency of the fan wheel 26. Because the inflection point 46 is set relatively far outward, at 75% of the distance between the outer ring 32 and the hub 24, the trailing edge 38 forms a third angle 50 of 54° relative to the tangential direction on one side of the hub 24. At this distance, the leading edge 36 forms a fourth angle 52 of approximately 105° relative to the tangential direction on one side of the hub 24.

[0050] This invention is not limited to the embodiments described above. Instead, those skilled in the art can derive other variations without departing from the subject matter of the invention. In particular, all the individual features described in connection with the embodiments can also be combined with each other in other ways without departing from the subject matter of the invention.

[0051] List of reference numerals

[0052] 2 motor vehicles

[0053] 4 internal combustion engines

[0054] 6 wheels

[0055] 8 radiator fans

[0056] 10 lines

[0057] 12 radiators

[0058] 14 Fan Cover

[0059] 16 electric motors

[0060] 18 Empty Sections

[0061] 20 Motor Holding Section

[0062] 22 Install support pillars

[0063] 24 hubs

[0064] 26 fan wheels

[0065] 28 Rotation axis

[0066] 30 fan blades

[0067] 32 outer ring

[0068] 34 dynamic pressure flap

[0069] 35° rotation direction

[0070] 36 front edge

[0071] 38-inch edge

[0072] 40 First Angle

[0073] 42 angle

[0074] 44 angle

[0075] 46 Turning Points

[0076] 48 Second Angle

[0077] 50 Third Angle

[0078] 52 Fourth Angle

Claims

1. A fan wheel (26) for a motor vehicle (2), the fan wheel having a hub (24) on which a plurality of sickle-shaped fan blades (30) are attached, each fan blade having a front edge (36) and a rear edge (38), and the front edge and the rear edge being attached to an outer ring (32) at their end sides, wherein, A first angle (40) is formed between the front edge (36) and the outer ring (32), and a second angle (48) is formed between the rear edge (38) and the outer ring (32), wherein both angles are greater than 90°.

2. The fan wheel (26) according to claim 1. Its features are, The fan blades (30) are forward-facing sickle-shaped.

3. The fan wheel (26) according to claim 2. Its features are, The rear edge (38) and the hub (24) form an angle (44) of less than 60°, and the front edge (36) and the hub (24) form an angle (42) of greater than 100°.

4. The fan wheel (26) according to any one of claims 1 to 3. Its features are, The first angle (40) is between 150° and 160°.

5. The fan wheel (26) according to any one of claims 1 to 4. Its features are, The second angle (48) is between 140° and 160°.

6. The fan wheel (26) according to any one of claims 1 to 5. Its features are, The front edge (36) is unidirectionally arched.

7. The fan wheel (26) according to any one of claims 1 to 6. Its features are, The arching behavior of the rear edge (38) changes at the inflection point (46).

8. The fan wheel (26) according to claim 7. Its features are, The distance between the inflection point (46) and the hub (24) is between 80% and 90% of the distance between the outer ring (32) and the hub (24).

9. A radiator fan (8), particularly a main fan, for a motor vehicle (2), the radiator fan having a fan shroud (14) having a circular opening (18) within which a fan wheel (26) according to any one of claims 1 to 8 is arranged, the fan wheel being driven by an electric motor (16) connected to the fan shroud (14).

Images