Method for cleaning a cooling device by shaking

Description

[0001] The invention relates to a method for cleaning a cooling device for a motor vehicle and to a cooling device configured to carry out the method. Furthermore, the invention relates to a motor vehicle having such a cooling device.

[0002] For the general state of the art, reference is made to JP H04 19322 A.

[0003] JP H04 19322 A discloses an engine compartment comprising an engine, a radiator, a fan for cooling the radiator, a hydraulically driven motor for driving the fan, and a control unit for switching the rotation direction of the motor. The hydraulically driven motor, which can rotate in both directions, is connected to a hydraulic circuit consisting of an oil pump and an oil switching valve. When the pneumatic pressure of a compartment is below a certain value or the water temperature in the radiator is higher than a certain value, the controller sends a signal to the oil switching valve to switch the flow of pressurized oil in the hydraulic circuit to the reverse direction, thus rotating the hydraulically driven motor and fan in the reverse direction to remove dust in the radiator.

[0004] The use of cooling circuits is well known for cooling vehicle components such as the traction battery, engine, etc. Heat is removed from the vehicle components to be cooled using a suitable coolant or refrigerant (e.g., water or oil) and released into the vehicle's environment. The heat exchange between the coolant or refrigerant and the vehicle's environment usually takes place via a heat exchanger or cooler through which the airflow flows. This can be designed, for example, as a tube / fin system, a so-called radiator network. To support the airflow, particularly when driving at low speeds and / or when there is a high cooling demand, these types of coolers often also have a fan, which can be driven, for example, by an engine output or a separate electric motor.

[0005] Particularly in agricultural applications and on construction sites, these vehicle fans / radiators are often exposed to increased levels of dust and dirt (e.g., mud, insects, plant debris, etc.). These contaminants can settle on the radiator / fan, thus reducing airflow and performance.

[0006] In the case of vehicles powered by combustion engines, the vibrations typically generated by the combustion engine provide a certain "self-cleaning effect," especially against larger particles. However, a disadvantage is often that, due to the usually rigid connection of the fan to the engine's crankshaft (e.g., via a belt drive), reversing the fan's rotation direction and thus blowing out the loosened contaminants is not possible.

[0007] In the case of electric motor-driven vehicles, the problem is that low-frequency vibrations are generally not generated by the ignition pulse, thus preventing a self-cleaning effect from combustion engine vibrations. Furthermore, in electric-driven vehicles (e.g., when using wheel hub motors or when using centrally or mid-vehicle-mounted drive motors), there is no direct mechanical coupling between the engine and the cooling system. Therefore, even if engine vibrations were to occur, they generally do not achieve a sufficient cleaning effect due to the lack of proximity to the fan / radiator.

[0008] Accordingly, the object of the invention is to provide an improved method for cleaning radiators compared to the prior art. In particular, the object of the invention is to provide a solution by which a contamination-related reduction in cooling performance of a fan and / or radiator can be avoided as far as possible.

[0009] This object can be achieved with the features of the independent claims. Advantageous embodiments and applications of the invention are the subject of the dependent claims and are explained in more detail in the following description, with partial reference to the figures.

[0010] According to a first independent solution, a method for cleaning a cooling device is provided. This can also be referred to below as a "cleaning method." The aforementioned cooling device is preferably a cooling device for a motor vehicle (e.g., for a car, truck, or bus). The cooling device has a heat exchanger (e.g., a coolant cooler) and an electric drive motor (e.g., a three-phase motor), wherein the drive motor is connected to the heat exchanger (e.g., via a fan shroud). Furthermore, the cooling device comprises a fan impeller (e.g., an axial fan impeller) that is drivingly connected to the drive motor. The fan impeller can thus be driven and / or set in rotation by means of the drive motor.

[0011] Furthermore, it is provided that the cleaning method comprises operating the cooling device in a shaking mode. The shaking mode should include controlling the current supply to the drive motor to generate a shaking movement of the heat exchanger, the drive motor, and / or the fan wheel. According to the invention, the shaking movement serves to shake off and / or loosen contaminants (such as dust, insects, and / or plant parts) from the cooling device (e.g., from the heat exchanger, the drive motor, and / or the fan wheel). If the cooling device additionally comprises a fan cover, the shaking movement can additionally or alternatively also include a shaking movement of the fan cover. A "shaking movement" can preferably be understood as a periodic or aperiodic oscillating movement of the corresponding component(s).For example, the shaking movement can include jerking, wobbling, and / or vibrating the corresponding component(s) at a specific vibration frequency. Such a temporary, targeted stimulation of a shaking movement—usually suppressed during normal operation due to noise and wear—can advantageously achieve a "self-cleaning" of the cooling device, as typical contamination of the cooling device can be detached and / or shaken off the components of the cooling device through resonance effects and / or jerky movements (similar to a carpet beater effect, possibly by utilizing a system-inherent and / or defined axial play in the fan drive). A particularly advantageous feature is that no external influence, e.g., is required.This means that cleaning is no longer necessary, i.e., human and / or mechanical cleaning, but can be achieved simply by modifying the control of the components usually present in coolers of this type. Accordingly, the attachment of additional cleaning components to the cooling device can also be advantageously eliminated.

[0012] According to a first aspect, the shaking movement can comprise a, preferably deliberately induced, vibration for shaking off contaminants and / or a, preferably deliberately induced, oscillating movement for shaking off contaminants. The contaminants are preferably dust, tire wear, mud, insects, and / or plant parts (such as awns and / or leaves). The term "deliberately induced" can preferably be understood to mean that the corresponding shaking movement is deliberately induced. In other words, that the corresponding shaking movement is not merely a potentially undesirable marginal phenomenon and / or a potentially undesirable side effect.

[0013] According to a further aspect, the vibrating movement can have a frequency in the range of 30 Hz to 3 kHz, preferably between 50 Hz and 2 kHz. By advantageously exploiting resonance effects, the low-frequency ranges (e.g., up to 300 Hz) can preferably serve to loosen and / or shake off more massive contaminants, whereas higher-frequency ranges (e.g., between 300 Hz and 2 kHz) can preferably serve to loosen and / or shake off very light contaminants. For example, in this context, the method can comprise controlling the current supply to the drive motor for the targeted excitation of a vibrating movement with one or more, preferably predetermined, frequencies, preferably in the range between 30 Hz and 3 kHz. Alternatively, the method can also comprise controlling the current supply to the drive motor to move through a, preferably predetermined, frequency range.

[0014] Additionally or alternatively, the vibration movement can have a frequency that corresponds to a resonant frequency of the cooling device. Depending on the coupling between the respective cooling device components, the "resonant frequency of the cooling device" can be a resonant frequency of the (quasi-free) heat exchanger, drive motor, or fan impeller, or of the entire system or a subset thereof. To determine corresponding resonant frequencies of the cooling device, for example, the largest possible frequency range can be traversed or tuned, and frequencies with high or maximum vibration amplitudes can be determined, which are then specifically excited during cleaning operation, i.e., when carrying out the claimed cleaning method.

[0015] Additionally or alternatively, the shaking movement can have an amplitude that is greater than during a non-cleaning operation of the cooling device. The non-cleaning operation can preferably be a cooling operation of the cooling device (e.g., a suction fan or pressure fan operation), in which an air flow that primarily cools the heat exchanger is generated. Alternatively, the non-cleaning operation can also be another operation of the cooling device that does not exactly correspond to the implementation of the claimed cleaning method.

[0016] According to a further aspect of the invention, controlling the current supply to the drive motor to generate the shaking movement can comprise at least one of the possibilities described below. In general, i.e., regardless of the specific implementation in the individual case, "controlling the current supply" can preferably be understood as controlling one (e.g., in the case of a single-phase motor) or several (e.g., in the case of a three-phase motor) currents flowing in the drive motor (e.g., their strength, phase, and / or frequency). This can, for example, comprise varying one or more supply voltages applied to the drive motor (e.g., in strength, phase, and / or frequency). By way of example only, in the case of a three-phase drive motor, control can be achieved by controlling a known H-bridge component connected upstream of the drive motor.By appropriately timing the IGBTs commonly used in conventional H-bridge components, not only can the output power of the drive motor be easily regulated, but also the uniformity of the rotational movement of its rotor shaft can be influenced.

[0017] Specifically to generate the shaking motion, controlling the current supply can involve staggered current supply to the drive motor. For example, the drive motor can be supplied with power for a certain period of time and then switched off for a certain period of time, with this sequence being continuously repeated. In other words, the staggered current supply can involve a constant alternation of "on phases" and "off phases" of the drive motor.

[0018] Furthermore, controlling the current supply can include a preferably periodic countercurrent braking of the drive motor. This can preferably be understood as a, preferably temporary, deceleration of the drive motor, e.g., by applying a rotation-inhibiting current. In addition to reversing the polarity of the supply voltage, this can also be achieved, for example, in the case of a three-phase asynchronous motor, by swapping two outer conductors. This advantageously allows for the targeted induction of shaking movements (such as vibration and / or jerking).

[0019] Furthermore, controlling the current supply to generate the shaking movement can include generating, preferably periodic, changes in the direction of rotation of the drive motor. For example, rapid changes in the direction of rotation (left / right rotation) can be made. Accordingly, this can also be referred to as a preferably provoked oscillating pendulum operation of the drive motor or fan wheel.

[0020] Furthermore, controlling the current supply can include generating a preferably periodic rotational irregularity of the drive motor. For example, the drive motor can be accelerated temporarily, preferably at regular intervals. In other words, an oscillating speed curve can be generated, for example, to thereby simulate a static imbalance. The resulting shaking movement is thus preferably an unbalance-excited vibration, although the drive motor itself should preferably not exhibit any static imbalance.

[0021] Furthermore, controlling the current supply can involve superimposing at least two of the aforementioned options. Overall, a vibrating movement of the cooling device components can thus be advantageously achieved simply by appropriately controlling the fan drive motor—which is often already present in devices of this type—so that additional components that trigger the detachment of contaminants (such as the installation of an additional (static) unbalance motor) can be advantageously dispensed with.

[0022] According to a further aspect, controlling the current supply to generate the vibrating movement can comprise pulse-modulated actuation of the drive motor with a predetermined pulse sequence. For example, the actuation can comprise pulse-width modulation, pulse-frequency modulation, and / or pulse-phase modulation—basically known in the prior art—whereby these techniques are preferably used in the present case for the targeted excitation of an oscillating movement, e.g., by generating rotational irregularity. For this purpose, a supply voltage can be applied to the drive motor, for example, which has a predetermined sequence of pulses (e.g., rectangular pulses), which cause a corresponding vibrating movement of the cooling device components.

[0023] For this purpose, according to a further aspect, the pulse sequence can deviate from a pulse sequence required for synchronous operation of the drive motor. In other words, the pulse sequence used to control the drive motor can be a pulse sequence that causes non-synchronous operation of the drive motor. For example, certain pulse periods, i.e., defined units consisting of a pulse and a pause, of a pulse sequence required for synchronous operation of the drive motor can be modified (e.g., the pulse width and / or pulse phase position of the pulses can be varied within the pulse periods). In this way, a vibration operation that deviates from smooth synchronous operation of the motor can be advantageously induced.

[0024] Additionally or alternatively, the control may comprise a (e.g., periodic) variation of pulses of the predetermined pulse sequence. For example, on-off cycles may be lengthened or shortened, on-off cycles may be subjected to energization, and / or phase shifts of the pulses may be performed. Thus, varying pulses preferably comprises changing a pulse width and / or pulse phase position of the pulses within the predetermined pulse sequence. The predetermined pulse sequence may, for example, be a pulse sequence required for synchronous operation of the drive motor.

[0025] According to a further aspect, the drive motor can be a high-voltage drive motor. The term "high-voltage drive motor" can preferably be understood to mean a drive motor that can be operated with an alternating voltage between 30 V and 1 kV and / or with a direct voltage between 60 V and 1.5 kV, particularly preferably between 400 V and 850 V. For example, the high-voltage drive motor can be designed as a three-phase asynchronous machine that can be operated with high-voltage three-phase current. This advantageously allows for a high overall cooling performance of the cooling device.

[0026] According to a further aspect, the cleaning method can further comprise operating the cooling device in a first airflow conveying mode. The first airflow conveying mode can comprise rotating the fan impeller in a first direction of rotation (e.g., rotating the fan impeller counterclockwise) to generate a first airflow. Preferably, the first airflow conveying mode or the first airflow serves to remove contaminants. For example, in this context, contaminants can initially be attached to or detached by the shaking mode, which are then stirred up in the first airflow conveying mode and transported away from the cooling device. In addition, the first airflow conveying mode can also control the current supply to generate a shaking movement. In other words, a type of mixed operation comprising shaking and airflow conveying can be provided.Alternatively, the first air flow conveying operation may also comprise solely rotating the fan wheel to generate the first air flow (without shaking) to remove impurities.

[0027] Additionally or alternatively, the cleaning method can further comprise operating the cooling device in a second air flow conveying mode. The second air flow conveying mode can comprise rotating the fan wheel in a second direction of rotation (e.g., rotating the fan wheel clockwise) to generate a second air flow. The second direction of rotation is preferably opposite to the first direction of rotation and / or the second air flow is opposite to the first air flow. The second air flow conveying mode or the second air flow preferably also serves to remove contaminants. In an embodiment that is merely an example, contaminants can first be attached to or detached by the shaking mode, which are then blown out of the cooling device by operation in the second air flow conveying mode.The second airflow is preferably an airflow directed away from the cooling device and / or an airflow directed opposite to the flow direction in (normal) cooling mode of the cooling device. In the second airflow conveying mode, the current supply can also be additionally controlled to generate a shaking movement, i.e., a mixed operation of shaking and airflow conveying. Alternatively, the second airflow conveying mode can also exclusively comprise rotating the fan impeller to generate the second airflow (without shaking) for removing contaminants.

[0028] In order to advantageously achieve the most comprehensive cleaning of the cooling device possible, it can be provided that the cooling device is operated in shaking mode and in the first air flow conveying mode and / or in the second air flow conveying mode in a predetermined, i.e. previously determined, time sequence. For example, the cleaning method can comprise operating the cooling device in shaking mode for 1 minute and then operating the cooling device in the first air flow conveying mode for 2 minutes, wherein, if necessary, this sequence can also be repeated multiple times, e.g. three times. In this context, the predetermined time sequence can preferably also be understood as a predetermined operating sequence or a predetermined cleaning program.

[0029] According to a further aspect, the predetermined temporal sequence can include operating the cooling device in the shaking mode, in the first airflow conveying mode, and in the second airflow conveying mode. In other words, the predetermined temporal sequence can include all three of the aforementioned operating modes. For example, the sequence can have the following defined sequence: clockwise rotation - counterclockwise rotation - shaking - clockwise rotation - counterclockwise rotation - shaking - clockwise rotation - counterclockwise rotation - shaking - etc. The combination of the various operating modes can advantageously achieve the best possible self-cleaning effect.

[0030] According to a further aspect, operating the cooling device in shaking mode and / or in the first airflow conveying mode and / or in the second airflow conveying mode can comprise at least temporarily operating the electric motor at a maximum speed and / or maximum power. Additionally or alternatively, operating the cooling device in shaking mode and / or in the first airflow conveying mode and / or in the second airflow conveying mode can comprise at least temporarily operating the electric motor at an increased speed and / or increased power compared to the non-cleaning mode. Preferably, the speed and / or power is higher than a speed and / or power used in the normal cooling mode of the cooling device. In this way, a stronger airflow can advantageously be generated as needed to promote the detachment and / or removal of contaminants.

[0031] The invention further relates to a cooling device. The cooling device is preferably a cooling device for a motor vehicle (e.g., for a car, truck, or bus). The corresponding cooling device has a heat exchanger (e.g., a coolant cooler) and an electric drive motor (e.g., a three-phase motor), wherein the drive motor is connected to the heat exchanger (e.g., via a fan shroud). Furthermore, the cooling device comprises a fan impeller (e.g., an axial fan impeller) that is drivingly connected to the drive motor. Furthermore, the cooling device comprises a control device (e.g., a control unit). The control device can be connected to the drive motor via signaling (e.g., via a corresponding control or signal line) or integrated directly into the drive motor.The control device should further be configured to carry out a method for cleaning the cooling device, as described in this document. The features described in connection with the cleaning method should also be considered disclosed and claimable in connection with the cooling device. The same applies vice versa. For example, the control device can be configured to carry out a cleaning mode, wherein the cleaning mode comprises controlling the current supply to the electric motor to generate a shaking movement of the heat exchanger, the drive motor, and / or the fan impeller, preferably for shaking off contaminants.

[0032] According to a first aspect, the cooling device can further comprise a diagnostic device. The diagnostic device can be part of the aforementioned control device or a separate unit (e.g., a component of a central vehicle control unit). The diagnostic device can be connected to the control device via signaling (e.g., via a corresponding control or signal line). Furthermore, the diagnostic device can be configured to generate a contamination signal that depends on contamination of the cooling device (e.g., clogging of the heat exchanger). For example, the diagnostic device can be configured to output the contamination signal when a predetermined contamination level (e.g., clogging) of the cooling device is exceeded. The diagnostic device is preferably configured to generate a contamination signal that depends on the degree of contamination of the cooling device (e.g.,to generate a contamination signal dependent on the degree of clogging of the heat exchanger. By way of example only, the diagnostic device can comprise optical and / or capacitive sensors for the direct detection of the contamination or the degree of contamination. In addition or alternatively, the diagnostic device can also evaluate the current consumption of the drive motor, the cooling capacity of the cooling device, the speed of the fan impeller and / or another variable dependent on the contamination of the cooling device using suitable sensors in order to determine the contamination or the degree of contamination based on their deviation from a clean reference state. For example, if a cooler core of the heat exchanger were to become completely clogged, the speed of the fan would increase sharply, as this would lead to pumping in the vacuum within the fan cover / fan frame (e.g. a funnel-shaped, closed area between the cooler core and the fan), which could, for example,could be used for contamination detection. Furthermore, the control device can be configured to initiate the method for cleaning the cooling device depending on the contamination signal (e.g., when a predetermined contamination signal threshold is exceeded), preferably automatically. "Initiating" can generally be an immediate start of the cleaning method or a determination or scheduling of a, preferably near-real-time, point in time at which the cleaning method will be carried out. This advantageously provides for a needs-based, autonomous self-cleaning of the cooling device, thereby avoiding unnecessary cleaning processes as far as possible.

[0033] In order to advantageously enable a "planned" start of the cleaning process, i.e., to postpone the start of the cleaning process in potentially undesirable (operating) situations of the cooling device or the motor vehicle (such as when parked in a closed garage and / or at night), according to a further aspect, the cooling device can further comprise a state detection device. The state detection device can be part of the aforementioned control device and / or diagnostic device or a separate unit (e.g., a component of a central vehicle control unit). Furthermore, the state detection device can be configured to generate a signal derived from operating state information of the cooling device (e.g., whether it is currently deactivated) and / or operating state information of the motor vehicle (e.g., whether it is parked, driving, and / or charging) and / or environmental information (e.g.,the time of day) of the cooling device and / or the motor vehicle. By way of example only, the environmental information can comprise location information, e.g. whether the cooling device or the motor vehicle is located on a motorway, a country road, a field, a depot, an outdoor parking lot and / or an indoor parking lot (e.g. garage and / or hall). In addition or alternatively, the environmental information can comprise time information, e.g. whether it is day or night. In addition or alternatively, the environmental information can also comprise environmental information, e.g. whether there are currently people and / or objects (e.g. a house wall) directly in front of the cooling device or the motor vehicle and / or whether there are restrictions at the location regarding noise and / or (fine) dust emissions.All of this information advantageously makes it possible to generate a status signal that can be used as a measure of whether carrying out the cleaning process is advisable or possible with regard to the (current) operating and / or environmental state of the cooling device or the motor vehicle. The control device can be configured to initiate the process for cleaning the cooling device depending on the status signal (e.g., upon the presence or absence of a predetermined status signal value). This means that the control device can preferably be configured to start or schedule the cleaning process based on the status signal, whereby an undesirable start of the cleaning process (e.g., within a closed space) due to the current operating and / or environmental state can be advantageously avoided as far as possible.

[0034] The invention further relates to a motor vehicle (e.g., a passenger car), wherein the motor vehicle comprises a cooling device as described in this document. In this case, all features described in connection with the cooling device itself or the method for cleaning the cooling device should also be disclosed and claimable in connection with the motor vehicle. The same should apply vice versa. In a particularly preferred variant, the cooling device can be mounted on the motor vehicle by means of a three-point bearing with suitable decoupling elements (e.g., rubber buffers). This advantageously ensures that the defined, forced shaking movement can be generated with low energy, on the one hand, and that the sometimes harsh cleaning process is transmitted to the motor vehicle only in a dampened manner for reasons of comfort, rather than excessively. The motor vehicle is preferably a commercial vehicle.The term "commercial vehicle" can be understood in particular as a motor vehicle whose design and equipment are specifically designed for the transport of goods and / or for towing one or more (e.g., agricultural) trailers. For example, the commercial vehicle can be a truck, a semi-trailer truck, a construction vehicle, and / or an agricultural machine (e.g., a tractor).

[0035] According to one aspect, the motor vehicle can be an electric vehicle. The term "electric vehicle" can preferably be understood to mean a motor vehicle that can be driven, preferably exclusively, by electrical energy (e.g., from a traction energy storage device). For example, the electric vehicle can be an electric tractor or an electric construction vehicle. Furthermore, said electric vehicle can have a high-voltage electrical system, via which the drive motor, preferably a high-voltage drive motor, of the cooling device can be supplied with electrical energy. For example, the high-voltage electrical system can comprise a traction energy storage device (e.g., a lithium high-voltage battery) and an inverter, wherein the traction energy storage device is connected or connectable to the drive motor via an inverter. The high-voltage electrical system can have a direct voltage between 60 V and 1.5 kV, preferably between 400 V and 850 V.In this way, a drive of the fan can be realized that is independent of the engine operation, whereby the connection to the high-voltage electrical system also enables the use of powerful drive motors.

[0036] The aspects and features of the invention described above can be combined with one another as desired, as long as they fall within the scope of the claims.

[0037] Further details and advantages of the invention are described below with reference to the accompanying drawings. They show: Figure 1: a schematic representation of a cooling device according to a first embodiment in a first operating state; Figure 2: a schematic representation of the cooling device according to the first embodiment in a second operating state; and Figure 3: a schematic representation of a cooling device according to a further embodiment.

[0038] Identical or functionally equivalent elements are described in all figures with the same reference numerals and some are not described separately.

[0039] Figure 1shows a schematic representation of a cooling device 10 according to a first embodiment in a first operating state. The cooling device 10, which can be used, for example, for traction battery, charge air, and / or oil cooling in a motor vehicle 20, has a heat exchanger 11 (e.g., a coolant cooler with a radiator network). This can, for example, be capable of being flowed through by a preferably liquid heat transfer medium and / or can be connected to a cooling or refrigerant circuit of the motor vehicle 20 (e.g., via corresponding pipe and / or hose connections 18). For example, the heat exchanger 11 can be fluidly connected to a pump, a heater, and / or a traction battery. Furthermore, the cooling device 10 comprises an electric drive motor 12 (e.g., a three-phase motor), which is connected to the heat exchanger 11, preferably in a vibration-transmitting manner.For example, the cooling device 10 can have a preferably funnel-shaped fan shroud 13 (e.g., an air box), as shown, via which the drive motor 12 is connected to the heat exchanger 11. Preferably, the drive motor 12 itself has no static imbalance. Furthermore, the cooling device 10 comprises a fan wheel 14 (e.g., an axial fan wheel) that is drivingly connected to the drive motor 12. For example, the fan wheel 14 can have a hub in which a shaft of the drive motor 12 is mounted. Preferably, the shaft or the fan bearing has a system-inherent and / or defined axial play in order to promote the generation or excitation of a shaking movement in the cooling device 10, as will be described in more detail below. Furthermore, the cooling device 10 comprises a control device 15 (e.g., a control unit).The control device 15 can be connected to the drive motor 12 for signaling purposes (e.g., via a signal line), as shown by way of example. Furthermore, the control device 15 can be connected to other vehicle control units (e.g., a master control unit of a chiller system and / or a central on-board computer), e.g., via a CAN bus. The control device 15 should also be configured to carry out a method for cleaning the cooling device 10, as described in this document. In other words, the control device 15 can be configured to control the supply of current to the drive motor 12 to generate a vibrating movement of the heat exchanger 11, the drive motor 12, and / or the fan wheel 14.For example only, the control device 15 can be configured to supply power to the drive motor 12 in a phased manner to generate the shaking movement and / or to operate it with a preferably periodic change in the direction of rotation. The shaking movement induced thereby preferably serves to shake off contaminants (such as dust, insects, and / or plant parts) from the cooling device 10. Figure 1The cooling device 10 is shown in a merely exemplary first operating state in which, in addition to or alternatively to a shaking movement, an air flow is also conveyed (see flow arrows). This can be achieved, for example, by rotating the fan wheel 14 in a first direction of rotation (e.g., counterclockwise rotation of the fan wheel 14) to generate a first air flow 19a. Preferably, the first air flow 19a, in addition to cooling the heat exchanger 11, also serves to remove loosened or shaken-off contaminants. The cooling device 10 can further comprise, for example, a three-point bearing with suitable decoupling elements for fastening the cooling device 10 to the motor vehicle 20.In this way, it can be advantageously achieved that, on the one hand, the defined, forced shaking movement can be generated with low energy and, on the other hand, the sometimes harsh cleaning process is not transmitted to the motor vehicle 20 excessively, but only in a dampened manner, for reasons of comfort.

[0040] In contrast, Figure 2 a schematic representation of the cooling device 10 according to the first embodiment in a second operating state. Here too - merely as an example - in addition to or as an alternative to a shaking movement, an air flow is also conveyed (see flow arrows), however, the second air flow 19b generated in this way is similar to the one previously described in Figure 1The second air flow 19b can be generated, for example, by rotating the fan wheel 14 in a second direction of rotation opposite to the first direction of rotation (e.g., by rotating the fan wheel 14 clockwise). Alternatively, the second air flow 19b can also be generated—with the same direction of rotation of the drive motor 12—by appropriate coupling and / or deflection elements and / or by changing the orientation of adjustable blade elements of the fan wheel 14. Preferably, the second air flow 19b is an air flow directed away from the cooling device 10 for blowing out loosened or shaken-off contaminants from the cooling device 10.In order to advantageously achieve the most comprehensive cleaning of the cooling device 10, it can also be provided that the cooling device 10 is operated in a predetermined temporal sequence of the aforementioned operating modes. For example, the sequence of 1 minute of shaking operation, 1 minute of first airflow conveying operation, 1 minute of shaking operation, and 1 minute of second airflow conveying operation can be repeated several times.

[0041] Figure 3shows a schematic representation of a cooling device 10 according to a further embodiment. In addition to the embodiment described above, the cooling device 10 shown here further comprises two further optional components, namely a diagnostic device 16 and a condition detection device 17. The diagnostic device 16, which can be connected to the control device 15, for example, via signaling (e.g. via a corresponding control or signal line), can be designed to generate a contamination signal SV dependent on contamination of the cooling device 10 (e.g., clogging of the heat exchanger 11). For example only, the diagnostic device 16 can comprise a sensor (not shown) (e.g., a camera device) for directly detecting the contamination or the degree of contamination.Additionally or alternatively, the diagnostic device 16 can also monitor a variable dependent on the contamination of the cooling device 10 (e.g., a current consumption of the drive motor 12, a cooling capacity of the cooling device 10, a speed of the fan impeller 14). Furthermore, the control device 15 can be configured to initiate the method for cleaning the cooling device 10 depending on SV (e.g., when a predetermined contamination signal threshold is exceeded), preferably automatically.

[0042] In order to advantageously enable a "planned" start of the cleaning process, i.e., to postpone the start of the cleaning process in the event of undesirable (operating) situations of the cooling device 10 (e.g., to comply with the noise regulations of the Federal Immission Control Act), the present exemplary cooling device 10 further comprises a state detection device 17. This can be connected to the control device 15 and / or the diagnostic device 16 via a signaling device (e.g., via a corresponding control or signal line). Furthermore, the state detection device 17 can, for example, be designed to generate a state signal SZ dependent on operating state information of the cooling device 10 (e.g., whether it is currently deactivated) and / or environmental information (e.g., the time of day) of the cooling device 10. For example, the state detection device 17 can, for this purpose, comprise corresponding sensors (not shown) (e.g.,a brightness sensor). Furthermore, the control device 15 can be configured to initiate the method for cleaning the cooling device 10 depending on the status signal SZ (e.g., upon the presence or absence of a predetermined status signal value), whereby an undesirable start of the cleaning method (e.g., within a closed room) due to the current operating and / or ambient state can be advantageously avoided as far as possible. List of reference symbols

[0043] 10Cooling device 11Heat exchanger 12Drive motor 13Fan cover 14Fan wheel 15Control device 16Diagnostic device 17Condition detection device 18Pipe and / or hose connection 19aFirst air flow 19bSecond air flow 20Vehicle SV Contamination signal SZ Condition signal

Claims

1. A method for cleaning a cooling device (10) for a motor vehicle (20), the cooling device (10) comprising a heat exchanger (11), an electric drive motor (12) connected to the heat exchanger (11), preferably via a fan cover (13); and a fan wheel (14) that is operatively connected to the drive motor (12), characterised in that the method comprises: operating the cooling device (10) in a shaking mode, comprising controlling a current supply to the drive motor (12) to generate a shaking movement of the heat exchanger (11), the drive motor (12) and / or the fan wheel (14) to shake impurities off the cooling device (10).

2. A method according to claim 1, characterised in that the shaking movement comprises a deliberately induced vibration and / or oscillating movement for shaking off impurities, preferably for shaking off dust, insects and / or plant parts.

3. A method according to one of the previous claims, characterised in that the shaking movement a) has a frequency in the range of 30 Hz to 3 kHz; and / or b) has a frequency that corresponds to a resonant frequency of the cooling device (10); and / or c) has an amplitude that is greater than during a non-cleaning operation of the cooling device (10).

4. A method according to one of the preceding claims, characterized in that controlling the energization of the drive motor (12) to generate the vibrating motion comprises: a) a pulsed energization of the drive motor (12); and / or b) a, preferably periodic, counter-current braking of the drive motor (12); and / or c) a generation of, preferably periodic, changes in the direction of rotation of the drive motor (12); and / or d) a generation of a, preferably periodic, non-uniform rotation of the drive motor (12); and / or e) a superimposition of at least two of the possibilities mentioned in a) to d).

5. A method according to one of the previous claims, characterised in that controlling the energisation to generate the vibratory movement comprises a pulse-modulated, preferably pulse-width modulated, driving of the drive motor (12) with a predetermined pulse sequence.

6. A method according to claim 5, characterised in that a) the pulse sequence differs from a pulse sequence required for synchronisation of the drive motor (12); and / or b) the control comprises a preferably periodic variation of pulses of the predetermined pulse sequence, preferably a changing of a pulse width and / or pulse phase angle of the pulses.

7. A method according to one of the previous claims, characterised in that the drive motor (12) is a high-voltage drive motor.

8. A method according to one of the previous claims, characterised by - operating the cooling device (10) in a first air flow conveying mode, comprising rotating the fan wheel (14) in a first direction of rotation to generate a first air flow (19a), preferably for removing impurities; and / or operating the cooling device (10) in a second air-stream conveying mode, comprising a rotation of the fan wheel (14) in a second direction of rotation, preferably opposite the first direction of rotation, for generating a second air stream (19b), preferably opposite the first air stream, preferably for the removal of impurities; wherein the cooling device (10) is operated in the shaking mode mode and in the first air current conveying mode and / or in the second air current conveying mode in a predetermined temporal sequence.

9. A method according to claim 8, characterised in that the predetermined temporal sequence comprises operating the cooling device (10) in the shaking mode, in the first air current conveying mode and in the second air current conveying mode.

10. A method according to claim 8 or 9, characterised in that the operation of the cooling device (10) in the shaking mode and / or in the first air flow conveying mode and / or in the second air flow conveying mode comprises an at least intermittent operation of the electric motor (12) at a maximum speed and / or a maximum power.

11. A cooling device (10) for a motor vehicle (20), comprising: - a heat exchanger (11); - an electric drive motor (12) which is connected to the heat exchanger (11), preferably via a fan cover (13); - a fan wheel (14) that is operatively connected to the drive motor (12); and - a control means (15) that is configured to execute a method for cleaning the cooling device (10) according to one of the preceding claims.

12. A cooling device according to claim 11, characterised in that the cooling device (10) comprises a diagnostic device (16) configured to generate a contamination signal (SV) dependent on a contamination, preferably on a degree of contamination, of the cooling device (10); wherein the control means (15) is configured to automatically initiate the procedure for cleaning the cooling device (10) automatically in dependence on the fouling signal (SV).

13. A cooling device (10) according to claim 11 or 12, characterised by a state detection device (17) configured to generate a state signal (SZ) dependent on operating state information and / or ambient information, e.g. time, location and / or environment information, of the cooling device (10) and / or the motor vehicle (20) ; wherein the control means (15) is configured to initiate the process for cleaning the cooling device (10) in dependence on the status signal (SZ).

14. A motor vehicle (20), preferably a utility vehicle, characterised by a cooling device (10) according to one of claims 11 to 13.

15. A motor vehicle (20) according to claim 14, characterised in that the motor vehicle (20) is an electric vehicle comprising a high-voltage electrical system via which the drive motor (12) of the cooling device (10) can be supplied with electric energy.