Electrically driven vehicle fan with planetary gears

Abstract

Vehicle fan (1), in particular for an electrically powered motor vehicle (18), comprising an electric drive motor (2), a fan wheel (3), a planetary gear (4), a sun gear (5), with at least three planet gears (6, 6', 6"), an output element (7), wherein the output element (7) has teeth (11), wherein the sun gear (5) is driven by the electric drive motor (2), characterized in that the output element (7) is integrated into the fan wheel (3).

Description

[0001] The invention relates to a vehicle fan and a motor vehicle according to the class of the independent patent claims.

[0002] EP 2 215 383 B1 discloses a fan comprising an electric drive motor, a fan wheel, and two planetary gears, each gear stage comprising a sun gear, several planetary gears, and an output element. The fan wheel is mounted on an axle arranged on one of the output elements and is driven by the drive device.

[0003] From CN 2 19 012 912 U a fan is known with an electric drive motor and a planetary gear, whereby the motor and the planetary gear are mounted on a bracket behind the fan blade.

[0004] From CN 2 13 298 225 U a fan for an air compressor is known that has a planetary gear.

[0005] From DE 10 2016 115 043 A1 a method for producing a ring gear for a planetary gear is known, wherein the ring gear has an internal toothing.

[0006] The object of the invention is to design a vehicle fan in such a way that a device with a particularly short axial length is created, which is also optimized with regard to noise development.

[0007] The vehicle fan according to the invention with the features of the independent patent claims has the advantage that by integrating the output element into the fan wheel and using only one planetary gear, a large part of the axial length of the drive device can be integrated into the hub of the fan, thus enabling a particularly compact design.

[0008] The particularly advantageous gear ratio and the resulting speeds enable particularly quiet operation.

[0009] Therefore, a vehicle fan according to claim 1 and the dependent claims as well as a motor vehicle with a vehicle fan according to claim 1 and the dependent claims are proposed here.

[0010] Therefore, a vehicle fan, in particular for an electrically driven motor vehicle, with an electric drive motor, with a fan wheel, with a planetary gear, with a sun wheel, with at least three planet wheels, with an output element, wherein the output element has teeth, wherein the sun wheel is driven by the electric drive motor, characterized in that the output element is integrated into the fan wheel.

[0011] A vehicle fan is a fan designed to draw in ambient air and direct it through a motor vehicle, for example, through a heat exchanger. The vehicle fan is driven by an electric motor. A fan wheel typically consists of blades shaped to generate an airflow when rotated. The blades may be enclosed by a fan ring at their widest point, but this is not mandatory, so a fan wheel can consist of several blades arranged around the circumference.

[0012] In a motor vehicle, heat from a variety of heat sources can be transferred via cooling or refrigeration circuits to a heat exchanger, where it can then be released into the environment. A heat exchanger is typically constructed from individual tubes containing a fluid designed to exchange heat with the environment. Corrugated fins are often also installed between the tubes to increase the surface area available for heat exchange.

[0013] The heat-exchanging fluid can be a water-based coolant that absorbs heat from, for example, an internal combustion engine, a battery, power electronics, an electric traction motor, or indirect heat exchangers, and then releases it to the environment in the heat exchanger. An indirect heat exchanger is a coolant-cooled heat exchanger in which the first fluid is the coolant from the coolant circuit, and another fluid is a fluid to be cooled, for example, intake air for an internal combustion engine or exhaust gas that needs to be cooled, or, for example, a refrigeration circuit of an air conditioning system or another coolant circuit.

[0014] However, the fluid could also be a refrigerant in an air conditioning or heat pump circuit, whereby the refrigerant can release or absorb heat in a heat exchanger through which ambient air flows, in particular a condenser or evaporator.

[0015] While the vehicle is moving, the airflow from the vehicle's airflow passes through the heat exchanger, allowing the continuous airflow to exchange heat with the surroundings. At varying speeds, when the vehicle is stationary, or when there is a very high need to dissipate heat, a vehicle fan actively pushes ambient air through the heat exchanger.

[0016] The vehicle fan is typically located in the front of the vehicle and can draw in ambient air through openings in the vehicle. In vehicles with a combustion engine, the vehicle fan is usually positioned behind the radiator as a suction fan or in front of the radiator as a pressure fan, thus ideally drawing in ambient air. The vehicle fan is usually located near the vehicle's radiator grille, through which ambient air is also drawn. In electrically powered vehicles, the radiator grille is often closed, so ambient air must be drawn in through other openings.

[0017] Installation space is always at a premium in the front of a vehicle, as the space is needed for other vehicle components or the combustion engine, for example. In electrically powered vehicles, the space left by the missing combustion engine is used for additional storage space, so every millimeter of added length, especially the axial length of a vehicle fan, represents a particularly advantageous competitive advantage.

[0018] The noise level of a vehicle fan is also an important factor in today's motor vehicles. As combustion engines become increasingly quieter, other noise sources such as the vehicle fan are coming into focus and can be perceived as annoying. This is particularly true in electrically powered vehicles, as the vehicle itself is very quiet and a loud vehicle fan is therefore perceived as particularly annoying. In addition, an electrically powered vehicle is also subject to additional challenges. For example, during a charging process, i.e. when the vehicle is parked, a significant amount of the waste heat generated during charging must be dissipated. Thus, under suitable ambient conditions, the vehicle fan can also be in operation when the vehicle is parked.In this situation, noise development is a crucial point, as you want to avoid disturbing passers-by, residents or even the driver with the loud noise of a vehicle fan.

[0019] A significant source of noise in a vehicle fan is the fan speed required for cooling. Fan speed is the speed measured directly on the fan wheel. Ideally, this is kept as low as possible. Modern electric motors usually operate particularly effectively at a relatively high speed range. This presents a dilemma when operating an electrically driven vehicle fan, as lower fan speeds are desired here. The torque required to drive a fan wheel is also usually quite high, meaning that particularly large and complex electric drive motors would have to be used. One solution is the use of a gearbox, which uses an appropriate gear ratio to convert a high motor speed into a slower fan speed with more torque. A disadvantage here is that a gearbox usually also requires a lot of installation space.

[0020] Therefore, a vehicle fan is proposed which combines an advantageously constructed electric drive motor and a particularly advantageously designed planetary gear and fan wheel, thus enabling a particularly compact vehicle fan which can be operated with little noise.

[0021] The vehicle fan, in particular for an electrically powered motor vehicle, has an electric drive motor and a fan impeller. The electric drive motor drives a planetary gear, which in turn drives the fan impeller. The planetary gear consists of a sun gear that is directly connected to the electric drive motor. The planetary gear also has an output element that is integrated into the fan impeller. The output element is shaped as a ring gear and has teeth on its inside that mesh with at least three planet gears, which also mesh with the sun gear. The planet gears are rotatably mounted so that a rotation of the sun gear drives the planet gears, which in turn set the output element in rotation. A transmission ratio can be achieved by appropriately selecting the appropriate teeth on the sun gear, planet gears, and output element.

[0022] The output element is integrated into the fan wheel. This could be achieved, for example, by a component firmly connected to the fan wheel. The component could be formed separately and then suitably attached to the fan wheel. It would be conceivable for such an output element to be designed as an annular body and then arranged on an end face of the fan wheel or in the area of ​​the fan wheel hub. The annular body could have gears formed on its inner circumferential surface that mesh with the gears of the planetary gears.

[0023] In a preferred, advantageous embodiment, the output element is integrated into the hub of the fan wheel, so that a large part of the planetary gear and the electric drive motor are arranged axially in the hub area of ​​the fan wheel. This enables a particularly short axial design.

[0024] In a further advantageous embodiment, the output element is formed integrally with the hub in such a way that the teeth of the output element are formed directly on the inside of the hub of the fan wheel. The fan wheel is preferably made, at least for the most part, from a plastic material. This can be conventional, well-known thermoplastic or thermosetting plastics, which are optionally reinforced with fillers such as fibers. Ideally, a fan wheel can be manufactured using an injection molding process directly with the teeth of the output element formed in the hub. However, the teeth can also be mechanically formed or reworked. It would also be conceivable for a separately manufactured output element to be overmolded with plastic. This would also make the use of different materials possible, e.g.another, particularly strong plastic or metallic material for the output element and a less strong and cheaper plastic material for the fan wheel.

[0025] In an advantageous, particularly preferred embodiment, the planetary gear has a gear ratio between 2:1 and 4:1. This allows fan speeds between 1,800 and 2,500 rpm, which are advantageous for noise generation, to be achieved. Due to the gear ratio, the electric drive motor can thus operate in a significantly higher, efficient speed range. This significantly reduces the noise generated by the fan impeller while maintaining a favorable efficiency. The electric drive motor can thus be designed for a higher speed and lower torque, making it more cost-effective to manufacture and more compact.

[0026] In a further advantageous embodiment, the planetary gears are made at least partially of a plastic material. The outer portion of the planetary gear, on its gear ring, can be made of a plastic material, while the inner bearing area can be made of a metallic material. Thus, the bearing, which is subject to particularly high stress, can be made of a stronger material, while the gearing is made of plastic.

[0027] Common thermoplastics or thermosetting plastics can be used as the plastic, optionally reinforced with fillers such as fibers. All known steel materials or even aluminum can be used as metallic materials. A standard bearing could also be used, which is either supported by another component made of a metallic material or a plastic component, or directly by the planetary gear.

[0028] Plastic gearing is particularly advantageous in terms of the noise generated by the planetary gear and also saves weight, which is also an important factor in a motor vehicle. The planetary gear can also be made entirely of plastic. A metal bearing can be overmolded with plastic to create the planetary gear. It can also be joined together by two or more separately manufactured components, particularly by hot-staking. Gluing or welding the two components together would also be possible.

[0029] With the integral arrangement of the output element in the hub, the planetary gear is at least partially integrated into the hub of the fan wheel. This optimizes the use of installation space and reduces the axial length.

[0030] In a further advantageous embodiment, the electric drive motor is a brushless DC motor with a fixed inner rotor and a rotatable outer rotor.

[0031] The inner rotor is typically equipped with wound coils that electrically generate a rotating magnetic field. The outer rotor, which can be equipped with permanent magnets, is mounted around the inner rotor. Motor designs that do not require permanent magnets are also known. This can be advantageous because the permanent magnets contain rare earth elements, the availability of which creates dependence on the availability of mining resources.

[0032] This type of rotor arrangement is also referred to as an external rotor motor. The electric drive motor does not require carbon brushes and is therefore brushless, enabling low-maintenance and particularly reliable operation. If an electric current needs to be transferred to the rotating outer rotor, as is necessary with a motor without permanent magnets, this can be done contactlessly using inductive technology.

[0033] The electronically controlled coils generate magnetic fields that circulate around the inner rotor. This sets the outer rotor in motion and pulls it along accordingly. The functional principles and specific control systems of electric motors are well known and will not be described in detail here. The technology offers many design possibilities that cannot be described in full detail here.

[0034] In a further advantageous embodiment, the sun gear is arranged directly on the outer rotor of the electric drive motor. It is conceivable for the sun gear to be hollow and to enclose the outer rotor of the electric drive motor. This allows the electric drive motor to extend into the plane of the planetary gear, which in turn can be arranged at least partially in the hub of the fan wheel, which is particularly advantageous for a short axial length. This allows at least part of the electric drive motor to also be immersed in the hub of the fan wheel.

[0035] However, it would also be conceivable for the sun gear to be arranged on the axial end face of the outer rotor, which would still allow for an axially compact design by omitting an output shaft, as would be necessary with an internal rotor drive motor.

[0036] The sun gear is preferably made of a plastic material and attached to the outer rotor by a clip device. Conventional, well-known thermoplastics or thermosetting plastics can be used as the plastic, optionally reinforced with fillers such as fibers.

[0037] The use of a clip connection enables quick and easy assembly, which is a clear advantage in industrial large-scale production. The clip device can, for example, be implemented by a clip attached to the sun gear, which engages in grooves or other suitable notches adapted to the contour of the clip, thus securing the sun gear. However, the clip device can also be implemented by inserted additional parts such as a spring element, which is compressed during assembly and then expands into a suitable groove in the assembled position, thus securing the sun gear. A groove can be implemented either in the sun gear or in the outer rotor, or in both components. Other intermediate parts are also conceivable. The desired clip function can be implemented using a variety of designs, which cannot be fully discussed here.

[0038] It goes without saying that instead of a clip connection, or in addition to a clip connection, other fastening elements, such as screws, can be used, so that only the positioning is achieved via a clip connection, while the sun gear is additionally secured using suitable fastening elements. The clip connection could thus serve as a pre-assembly tool to simplify the assembly process by pre-positioning the component.

[0039] In a further advantageous embodiment, the electric drive motor has a motor housing. This protects the electrical and mechanical components from environmental influences. The housing could also accommodate the power electronics required to control the electric drive motor. The motor housing is made at least partially of a metallic material, in particular an aluminum material. However, it can also be partially made of a plastic material. Commonly known thermoplastics or thermosetting plastics, optionally reinforced with fillers such as fibers, are suitable for this purpose.

[0040] The motor housing can be constructed from several individual components and, for example, have a main body closed by a cover. The motor housing can also be partially recessed into the hub of the fan wheel, thus protecting the planetary gear, which is also partially located in the hub. However, it would also be conceivable to provide a separate housing for this, which could also be connected to the motor housing.

[0041] In a further embodiment of the invention, cooling fins are arranged on the motor housing. The cooling fins serve to assist in the dissipation of heat from the electric drive motor, which is generated during operation of the electric drive motor and planetary gear, in the power electronics, and in the mechanical and electrical components. This is particularly important because a large part of the drive device is enclosed in the hub, making heat dissipation from this difficult.

[0042] In a further embodiment of the invention, fastening points can be arranged on the motor housing. These are preferably at least two fastening points, which enable the vehicle fan to be firmly connected to a motor vehicle. The vehicle fan can be fastened directly to a frame of the motor vehicle or to a casing, which in turn is fastened to the motor vehicle. By fastening using central fastening points, the vehicle fan can be installed in the motor vehicle particularly easily and flexibly. The fastening point can be shaped in many different ways. For example, as a type of eyelet provided with corresponding openings in the plastic or the material used in the housing to allow suitable fastening devices, such as screws, to be inserted through. It would also be conceivable to design the fastening points as additional components, which in turn are firmly attached to the housing.

[0043] In a further advantageous embodiment of the invention, the electric drive motor is operated with a supply voltage greater than 300 V. Battery-electric vehicles have battery voltages ranging from 300 V to 1000 V, thus enabling the use of a particularly powerful drive motor with a very compact design. The use of a higher voltage enables better and lower-loss energy transfer than would be possible with a lower voltage of, for example, 12 V. However, it would also be conceivable to operate the motor with a voltage of, for example, 48 V.

[0044] Further advantageous embodiments of the invention are described in the following figures. These show: Fig. 1 a vehicle fan according to the invention. Fig. 2a a schematic view of a planetary gear. Fig. 2b shows an example design of a fan wheel. Fig. 2c an example view of a planetary gear. Fig. 3 the schematic structure of an electric drive motor according to the invention. Fig. 4 a schematic representation of a motor vehicle according to the invention. Preferred embodiment of the invention

[0045] The Fig. 1 shows a vehicle fan 1 according to the invention with a fan wheel 3 having a hub 12, wherein a drive device 13 consisting of a planetary gear 4 and an electric drive motor 2 is arranged in the hub 12. The fan wheel 3 is rotatably mounted and driven by the drive device 13. A large part of the drive device 13 is integrated into the hub 12 of the fan wheel 3 and is received thereby. The output element 7 is integrated into the fan wheel 3. For this purpose, the inner side of the hub 12 has a plurality of teeth 11 that mesh with the planetary gears 6, 6', 6" and transmit a torque of the planetary gear 4 to the fan wheel 3. By integrating the drive device 13 into the hub 12 and incorporating the fan wheel 3 as the output element 7, a particularly compact design, in particular an axially particularly short design, of the vehicle fan 1 is possible.

[0046] The fan wheel 3 has a blade structure that, depending on the design, generates an airflow when the fan wheel 3 rotates. The individual blades 22 can be enclosed by a circumferential blade ring 23. However, fan wheels 3 are also conceivable that do not have a blade ring 23, so that the blades 22 are not connected at their ends. The selection of the fan wheel 3 is a matter of design and depends on the installation situation in the motor vehicle 18 and the required ventilation performance requirements.

[0047] The electric drive motor 2 has a motor housing 10 that protects the electrical components from environmental influences. The motor housing is made at least partially of a metallic material, in particular an aluminum material. However, it can also be partially made of a plastic material. The motor housing can be made of several individual components and, for example, have a main body that is closed by a cover.

[0048] At least two fastening points 8 are arranged on the motor housing 10, which enable the vehicle fan 1 to be firmly connected to a motor vehicle 18. The vehicle fan 1 can be attached directly to a frame of the motor vehicle 18 or to a casing 20, which in turn is attached to the motor vehicle 18. By attaching it using central fastening points 8, the vehicle fan 1 can be mounted particularly easily and flexibly in the motor vehicle 18.

[0049] The motor housing 10 also has cooling fins 9, which serve to assist in the dissipation of heat from the electric drive motor 2, which is generated during operation of the electric drive motor 2 and planetary gear 4, in the power electronics, and in the mechanical and electrical components. This is particularly important since a large portion of the drive device 13 is enclosed in the hub 12, thus making heat dissipation difficult.

[0050] The Fig. Figure 2a shows the schematic structure of a planetary gear 4. It consists of a centrally arranged sun gear 5, which is driven by the electric drive motor 2. The sun gear 5 has teeth on its outer surface. The sun gear 5 can be hollow so that it can partially accommodate parts of the electric drive motor 2. This can, for example, be the outer rotor 14 of the electric motor 2. This, in turn, makes it possible to save installation space along the axial length.

[0051] At least three planetary gears 6, 6', 6" are arranged around the sun gear 5, which also have teeth on their outer side and are rotatably mounted in a device. The planetary gears are in turn encompassed by an output element 7, which has teeth 11 on its inner side. The planetary gears are in engagement with the teeth of the sun gear 5 and the output element 7. Thus, by appropriately designing the respective number of teeth on the sun gear 5, the planetary gears 6, 6', 6" and the output element 7, an increase or decrease in the speed of the electric drive motor 2 to the fan wheel 3 arranged on the output element 7 can be realized.Particularly preferably, the planetary gear has a gear ratio of 2:1 to 4:1, which means that, for example, with a gear ratio of 2:1, the speed of the electric drive motor 2 of 4000 rpm is reduced to a fan wheel 3 speed of 2000 rpm.

[0052] The Fig. Figure 2b shows a fan wheel 3 according to the invention for a motor vehicle fan 1. It has a hub 12 arranged in the center of the fan wheel 3. On the outside of the hub 12, several blades 22 are arranged, which can generate an airflow when the fan wheel 3 rotates. In the embodiment shown, the blades 22 are enclosed by a fan ring 23. Depending on the installation situation, this can increase the performance of the motor vehicle fan 1 and minimize noise. However, fan wheels 3 that do not have a fan ring 23 are also possible.

[0053] The hub 12 of the fan wheel 3 has an output element 7 with teeth 11 on its inner side. The output element 7 is therefore integrally formed by the hub 12. The teeth 11 of the output element 7 mesh with the planetary gears 6, 6', 6" of the planetary gear 4, thus enabling the drive of the fan wheel 3. The integration of the output element 7 into the fan wheel 3 enables a particularly compact design of the motor vehicle fan 1.

[0054] The Fig. Figure 2c shows an exemplary view of a planetary gear 6, 6', 6" of the planetary gear 4. The planetary gear 6, 6', 6" is shaped like a gear and has teeth on its outer side. It is made at least partially of a plastic material. Thus, the outer part with the teeth can be made of a plastic material, and the inner part of the planetary gear 6, 6', 6" can be made of a metallic material. This allows the particularly stressed bearing 21 of the planetary gear 6, 6', 6" to be made of a metallic material. The partial use of a plastic material advantageously reduces the weight of the respective planetary gear 6, 6', 6". The plastic material can be overmolded around the metallic bearing 21, or the plastic part can be manufactured separately and then mechanically caulked to the metallic bearing 21.This can also be done, for example, by hot caulking, where one of the parts is heated to facilitate assembly.

[0055] The Fig. Figure 3 shows the schematic structure of an electric drive motor 2. The electric drive motor 2 drives the fan wheel 3 and is designed as a brushless DC motor. In the embodiment shown, the drive motor 2 consists of a stationary inner rotor 15, which is usually equipped with wound coils that electrically generate a rotating magnetic field. A rotatably mounted outer rotor 14, which is usually equipped with permanent magnets, is arranged around the inner rotor 15. This motor configuration is also referred to as an external rotor motor. The electric drive motor 2 does not require any carbon loops and is therefore brushless, which enables low-maintenance and particularly reliable operation. The coils, controlled by electronics, generate magnetic fields that circulate around the inner rotor 15. This sets the outer rotor 14 in motion and pulls it along accordingly.

[0056] Operating voltages of 12 V or higher can be used. For particularly powerful motor operation, the use of voltages greater than 48 V, or in a particularly preferred embodiment, greater than 300 V, is advantageous. Battery-electric motor vehicles 18 have battery voltages ranging from 300 V to 1000 V and can thus enable a particularly powerful drive motor 2 with a very compact design.

[0057] The use of an external rotor motor has the great advantage that the outer rotor 14 rotates around the inner rotor 15 and thus the rotary movement can be transmitted through components attached to the outer rotor 14, such as the sun gear 5, whereas an internal rotor motor has to transmit the rotary movement outwards through a shaft.

[0058] In the illustrated embodiment, the sun gear 5 is mounted directly on the outer rotor 14. It thus encompasses the outer rotor 14, allowing the drive motor 2 to extend into the plane of the planetary gear 4. This can save axial space. However, it would also be conceivable for the sun gear 5 to be arranged on the axial end face of the outer rotor 14, which would still allow for a compact design.

[0059] The sun gear 5 itself has corresponding teeth arranged on its outer side, which mesh with the planet gears 6, 6', 6" in the planetary gear 4.

[0060] Preferably, the sun gear 5 is made of a plastic material and fastened to the outer rotor 14 by a clip device 17. This enables simple and quick assembly, which is a significant advantage in industrial large-scale production. The clip device 17 can, for example, be implemented by a clip attached to the sun gear, which engages in grooves or other suitable notches adapted to the contour of the clip and thus fixes the sun gear 5. However, the clip device can also be implemented by inserted additional parts such as a spring element, which is compressed during assembly and then expands into a suitable groove in the assembled position, thus fixing the sun gear 5. A groove can be implemented either in the sun gear 5 or in the outer rotor 14, or in both components. Other intermediate parts would also be conceivable.A multitude of possible advantageous designs are conceivable, not all of which can be presented conclusively.

[0061] An additional anti-rotation device 16 can also be provided, which is advantageous for optimal transmission of torque from the outer rotor 14 to the sun gear 5. This can be implemented, for example, by an axially extending groove in the sun gear 5. An additional component or a corresponding elevation of the outer rotor 14 can engage in this groove.

[0062] The embodiment shown is not exhaustive and shows only one of the possible inventive embodiments for an electric drive motor 2.

[0063] The Fig.4 schematically shows a motor vehicle 18 with a vehicle fan 1. One vehicle fan 1 is usually arranged in the front region of the motor vehicle 18, through which ambient air can flow. The vehicle fan 1 can be arranged in a passenger car, as well as in a truck or another vehicle, such as a construction vehicle or an agricultural vehicle. Since the vehicle fan 1 is electrically driven, it is preferably arranged in an electrically driven motor vehicle 18. This can be the case with a battery-electric motor vehicle 18 or with a motor vehicle 18 with a fuel cell drive. However, an arrangement in a hybrid motor vehicle 18 with an electric drive and an internal combustion engine, but also in motor vehicles 18 powered purely by an internal combustion engine would be conceivable.

[0064] The vehicle fan 1 is positioned in a space having inlets to the environment so that ambient air can be sucked in. This can be behind a radiator grille or elsewhere in the front area of ​​the motor vehicle 18. Purely battery-electric vehicles often have closed radiator grilles, so that the air is sucked in from other openings or from the underbody. The vehicle fan 1 can be mounted on a frame 20, which is then itself connected to the motor vehicle 18. Such a frame 20 is usually made of a plastic material and usually provides an opening for the fan wheel 3 and corresponding mounting devices for installing the vehicle fan 1. The fastening points 8 arranged on the engine housing 10 can be used for this purpose. One or more heat exchangers 19 can be arranged behind or in front of the vehicle fan 1.The vehicle fan 1 allows ambient air to be supplied to the heat exchangers 19, particularly when driving slowly, at different speeds, or when stationary, for example, while waiting at a traffic light or during a charging process, so that heat can be dissipated therefrom. However, the vehicle fan 1 can also serve to support the supply of ambient air while the motor vehicle 18 is moving, particularly when a large amount of heat is required and the ambient air supplied by the airstream is no longer sufficient. List of reference symbols 1 vehicle fan 2 Electric drive motor 3 Fan wheel 4 planetary gears 5 Sun gear 6, 6', 6'' planetary gear 7 Output element 8 attachment point 9 cooling fins 10 engine housing 11 teeth of the output element 12 Hub 13 Drive device 14 Outer rotor 15 inner rotor 16 Anti-twist device 17 Clip device 18 Motor vehicle 19 heat exchangers 20 frame 21 Storage 22 shovels 23 Fan ring

Claims

[1] Vehicle fan (1), in particular for an electrically driven motor vehicle (18), with an electric drive motor (2), with a fan wheel (3), with a planetary gear (4), with a sun wheel (5), with at least three planet wheels (6, 6', 6"), with an output element (7), wherein the output element (7) has teeth (11), wherein the sun wheel (5) is driven by the electric drive motor (2), characterized by that the output element (7) is integrated into the fan wheel (3). [2] Vehicle fan (1) according to claim 1, characterized by that the teeth (11) of the output element (7) are integrally formed in a hub (12) of the fan wheel (3) and the fan wheel (3) consists at least partially of a plastic material. [3] Vehicle fan (1) according to claim 1 or 2, characterized by that the planetary gear (4) has a gear ratio between 2:1 and 4:1 and a fan speed between 1,800 rpm and 2,500 rpm. [4] Vehicle fan (1) according to one of the preceding claims, characterized by that the planetary gears (6, 6', 6") consist at least partially of a plastic material. [5] Vehicle fan (1) according to one of the preceding claims, characterized by that the electric drive motor (2) is a brushless direct current motor (BLDC) having a fixed inner rotor (15) and a rotatable outer rotor (16). [6] Vehicle fan (1) according to one of the preceding claims 2 to 5, characterized by that the electric drive motor (2) has a motor housing (10) that protrudes at least partially from the hub (12) and has cooling fins (9) arranged at least partially on its outer side. [7] Vehicle fan (1) according to claim 6, characterized by that the motor housing (10) has on its outside at least two fastening points (8) for mounting the vehicle fan (1) on a motor vehicle (7). [8] Vehicle fan (1) according to one of the preceding claims 5 to 7, characterized by that the sun gear (5) consists of a plastic material and is clipped onto the outer rotor (14) by means of a clip device (17). [9] Vehicle fan (1) according to one of the preceding claims, characterized by that the electric drive motor (2) is operated with a voltage greater than 300 V. [10] Motor vehicle (7) with a vehicle fan (1) according to one of the preceding claims.

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