Fan drive device

The invention relates to a fan drive device (1) for driving at least one fan impeller (2), comprising at least one first drivable coolable housing element (9, 10) with at least one output disc (13) which can be connected to the at least one drivable coolable housing element (9, 10) in such a way as to be capable of transmitting torque by fluid friction, wherein at least one fluid can be admitted to at least one torque-transmitting space, and the mass flow of said fluid can be regulated by means of a valve element (30), wherein the valve element (30) can be actuated by at least one actuator (26, 27), and at least a section of the actuator (26, 27) is arranged in at least one retaining element (33) for fastening to a motor unit.

The present invention relates to a fan drive device for driving at least one impeller wheel.

Fans are known for cooling heat exchangers such as coolant coolers, charge air coolers, oil coolers, condensers for air conditioning systems, gas coolers for air conditioning systems etc. These fans are driven by means of at least one electric drive unit and/or by means of at least one fluid friction clutch.

The fans are used in particular for cooling the engine of motor vehicles with internal combustion engines. Said fans are frequently arranged on a separate bearing journal on the end wall of the engine. The fans are usually driven or can be driven by means of a belt drive.

Clutch devices are known which permit engagement and disengagement of the clutch according to the principle of dry friction. These clutch devices can be activated pneumatically or electromagnetically. These clutch devices usually have a belt pulley with which the belt drive can be driven. The bearing of the drivable belt pulley usually has a nonrotating bearing journal. In addition, the clutch device usually has pneumatic or electromagnetic activation devices. During assembly, the clutch device is usually firstly fastened to an end wall of the engine without a fan, in particular an impeller wheel, and connected to the belt drive. The fan, in particular the impeller wheel, is mounted subsequently.

This assembly sequence is particularly advantageous with clutch devices on which a large weight is acting.

The known clutch devices have infinitely variable regulation of the output speed. The fan is either entrained directly in a frictionally locking fashion or it remains at a very low idling speed over the residual drag torque of the bearing. Requirements such as a higher fan power, lower generation of noise and better utilization of energy cannot be met with the described fans.

Therefore, if the low idling speed is not sufficient during operation, the fan is activated to the maximum extent. This consumes a very large amount of energy and causes noise to be generated, which adversely affects the traveling comfort of a vehicle occupant.

In addition, fan drive devices which are regulated continuously are known according to the principle of fluid friction. Before assembly, these fan drive devices are connected to the fan. The vehicle usually has a bearing unit which is premounted, in particular on the end wall of the engine. A belt pulley, which is driven with a belt, is usually arranged on the bearing unit. During assembly of the vehicle, a rotating hub is subsequently pushed onto a premounted unit which is usually composed of a fan and fan drive device. Owing to the heavy weight which acts on the elements to be mounted, the assembly process is usually very strenuous. In the case of fan drive devices which function according to the principle of fluid friction, the drive device is controlled directly by means of the temperature, for example by means of a bimetal. For this purpose, the bimetal activation device is usually arranged on the rotating end side of the drive device since the temperature of the cooling air flowing out of the vehicle cooler is used as a controlled variable.

In addition to the actuation of fluid friction clutches by means of bimetal, fluid friction clutches which can be actuated electromagnetically are known. They use a nonrotating solenoid. This nonrotating solenoid requires an additional bearing compared to a fluid friction clutch which is actuated by means of bimetal. In addition, it is necessary to support the electrical connection in the region of rotating components.

Fan drive devices which function according to the fluid friction principle have slip power which generates heat. The heat causes the clutch components to heat up. The slip power which is generated is proportional to the transmitted torque and proportional to the difference between the drive speed and output speed. The fan drive device, in particular the fluid friction clutch, has components which must not exceed a specific temperature. These components are, for example, bearings, in particular roller bearings. In order to drive the generated heat from the clutch, the housing of the clutch is usually provided with cooling fins which are intended to improve the transmission of heat to the surrounding air. These cooling fins are usually arranged radially on the rotating clutch housing.

Fan drive devices are known in which the clutch housing of a fluid friction clutch rotates at the rotational speed of the fan, in particular of the impeller wheel. The rotational speed of the fan, in particular of the impeller wheel, is lower than the drive speed. When the clutch housing rotates, the centrifugal force gives rise to forced convection which increases with the square of the rotational speed of the clutch housing. Given a low degree of activation of the fan, i.e. at a low output speed, the clutch housing is cooled to a relatively small degree. Given degrees of activation of 30% to 70%, a particularly large amount of heat is generated. The maximum deficit in the thermal balance is usually in the range from 30% to 40% of activation of the fan since the dissipated thermal power is at a minimum.

DE 103 38 432 A1 discloses a fluid friction clutch, in particular for a motor vehicle fan. The fluid friction clutch has, in the state in which it is disengaged from the drive element and output element, a reservoir space in the drive element which largely accommodates the hydraulic fluid. When the clutch is activated, the hydraulic fluid passes from the reservoir space into the clutch region. The hydraulic fluid at least partially closes the gap between the drive element and output element in the clutch region and causes a torque to be transmitted. The output element has concentric projections. In addition, the clutch device from DE 103 38 432 A1 has a controllable device for closing and opening flow paths. In a first position, the device opens the flow path for the inflow of hydraulic fluid into the clutch region and closes the return flow. In a second position, the device closes the inflow and opens the return flow. The torque device essentially has a magnet armature which is connected to the control shaft in a frictionally locking fashion, a flux U conducting ring which is connected to the drive shaft in a frictionally locking fashion and a coil which is arranged in the housing in a rotationally fixed fashion. If the coil is energized, a current-dependent torque is produced between the magnet armature and the flux-conducting ring and the control shaft is rotated relative to the drive shaft. The electromagnetically controlled torque and control device is composed of a rotationally fixed coil part which is secured on the drive shaft by means of a roller bearing, and the adjustment elements which rotate with the output shaft.

DE 103 24 314 A1 discloses a fan drive for motor vehicles. In said document, a fluid friction clutch is arranged on a secondary assembly. As a result, the fluid friction clutch is cooled better because it runs at a relatively high rotational speed and has a better supply of cooling air than if it were integrated into the fan hub. DE 103 24 314 A1 discloses a fan drive with a belt pulley. The driven belt pulley is connected to the housing or to a housing lid in a rotationally fixed fashion by means of screws, and is supported in a rotatable fashion on the drive shaft by means of a bearing. As a result, the belt drive is driven directly onto the housing, i.e. the output side of the clutch. The belt pulley drives a drive shaft by means of a freewheel, and therefore drives the housing including the fan. If the belt drive is activated via the clutch, the rotational speed of the belt pulley is higher than that of the drive shaft, as a result of which the housing is entrained directly via the belt pulley, and the freewheel rolls over the drive shaft. Drive is no longer provided by the flange shaft. The fan therefore runs at an increased rotational speed. In addition, DE 103 24 314 A1 discloses a fluid friction clutch which itself also runs at an increased rotational speed and is cooled better at the front, as a result of which it can dissipate a higher power loss or slip power.

DE 10 2004 009 073 A1 discloses an adjustable drive for a water pump in a motor vehicle. The adjustable drive has a rotatably mounted shaft on which at least one output element which is mounted in a rotationally fixed fashion and at least one drive element which is mounted in a rotatable fashion are arranged. A clutch region, which can hold a viscous fluid, is arranged between the drive element and the output element.

The adjustable drive has at least one first and at least one second flow path which connects a fluid reservoir space to the clutch region between the drive element and the output element. The adjustable drive also has a device whose position can be varied with at least one actuator which changes at least one through-opening of at least one flow path of the drive. The valves are activated with the at least one actuator. The at least one actuator is arranged outside the rotating clutch. The valves can be controlled magnetically. These are, in particular, seat valves. The magnetically controllable device has at least one axially movable armature on which a magnetic actuating force acts. A pulse transmitter for determining the rotational speed is provided on the shaft of the drive and/or of the coolant pump.

The object of the present invention is to improve a fan drive device of the type mentioned at the beginning.

A fan drive device for driving at least one impeller wheel is proposed, which fan drive device has at least one first drivable coolable housing element, at least one output disk which can be connected to the at least one drivable coolable housing element in such a way that it can transmit torque by fluid friction, wherein at least one fluid can be admitted to at least one torque-transmitting space, and the mass flow of said fluid can be regulated by means of a valve element, wherein the valve element can be activated with at least one actuator, wherein the actuator is arranged, at least in certain sections, in at least one retaining element for fastening to an engine unit.

The at least one first housing element is drivable or can be driven or is driven. In addition, the at least one housing element is coolable or can be cooled or is cooled. The at least one drive disk is connectable or can be connected or is connected to the at least one drivable coolable housing element in such a way that it can transmit torque by fluid friction.

The phrase can transmit torque by fluid friction is to be understood as meaning that, owing to frictional forces which act between particles of a fluid, at least one torque can be transmitted or is transmitted between the at least one first housing element and the at least one output disk.

At least one fluid can be admitted or is admitted to at least one torque-transmitting space.

Torque-transmitting space is to be understood as meaning, in particular, a space which is formed in at least one first housing element. In this space, the torque can be transmitted from the at least one first drivable coolable housing element to the at least one output disk, in particular by fluid friction.

The mass flow of the fluid, in particular of the viscous fluid, can be regulated or is regulated by means of a valve element. The valve element can be activated or is activated with at least one actuator. An actuator is to be understood here as meaning, in particular, a coil, in particular a solenoid.

The actuator, in particular the coil, is arranged, at least in certain sections, in at least one retaining element for fastening to an engine unit.

In this context, the actuator can be arranged in its entirety or only in certain sections or partially in the at least one retaining element.

A retaining element may be understood to be, in particular, a flange which can be used for fastening to an engine unit. In this context, the at least one retaining element, in particular the flange, can have at least one bore or at least one duct or at least one opening in which the actuator can be arranged.

In addition, a fan drive device is proposed, with at least one sensor being arranged, at least in certain sections, in the at least one retaining element for fastening to an engine unit.

The sensor here may be a rotational speed sensor which can measure, for example, an output speed or drive speed. In addition, the sensor can be for measuring temperature. The sensor is arranged here, at least in certain sections, in the at least one retaining element. The retaining element can be understood in particular as being a flange for fastening to an engine unit. The sensor may be arranged completely or only in certain sections or partially in the retaining element here. The retaining element may have an opening, at least a bore or at least a duct, in which the sensor can be arranged.

In addition, a fan drive device is proposed, wherein the actuator is arranged on the retaining element, and the at least one sensor is arranged, at least in certain sections, in the at least one retaining element.

The actuator can be, in particular, a coil, in particular a solenoid, which can be arranged on the retaining element and/or connected, at least in certain sections, to the retaining element or fastened, at least in certain sections, on the retaining element. The retaining element can be understood, in particular, to be a flange. At least one sensor can be arranged completely or at least in certain sections or partially in the at least one retaining element. The sensor can be a sensor for measuring rotational speed and/or a sensor for measuring temperature.

In addition, a fan drive device is proposed, wherein the actuator is arranged on a coolant pump, and at least one hub and one belt pulley are embodied in such a way that they conduct magnetic flux.

The actuator can be a coil, in particular a solenoid, which is arranged on a coolant pump. The coolant pump may be used here to pump coolant, in particular a cooling fluid, in particular cooling water, of a coolant cooler.

Hub is to be understood here in particular as being a bore-shaped cutout in a component which is or can be connected to a shaft. At least one hub and a belt pulley are embodied in such a way that they can conduct magnetic flux.

The phrase can conduct magnetic flux is to be understood here as meaning the at least one hub and the at least one belt pulley are formed from a material which conducts the magnetic flux.

In one advantageous refinement, the actuator is a solenoid. The solenoid is particularly advantageous since it can be actuated in a cost-effective and simple way.

In one advantageous development, the at least first housing element can be driven by means of the at least one belt pulley. In particular, the at least one belt pulley can drive, or drives, the at least first housing element. The housing element can particularly advantageously be driven at a high drive speed, wherein the at least first housing element can be cooled in a particularly advantageous way.

In one preferred embodiment, a viscous fluid can be admitted or is admitted to the torque-transmitting space through at least one bore. In particular, the viscous fluid can flow into the torque-transmitting space through the at least one bore. In this way different torques can be transmitted particularly advantageously from the at least one housing element to the at least one drive disk.

Furthermore, it can particularly preferably be provided that the retaining element is a flange which is arranged in a rotationally fixed fashion. The retaining element can particularly advantageously be arranged on or fastened to an engine unit.

In addition it is possible to provide that the first housing element and/or at least one second housing element have first concentric labyrinthine cutouts, and the output disk has second concentric labyrinthine cutouts corresponding thereto.

In this way, at least one torque, in particular different torques, can be particularly advantageously transmitted from the first housing element and/or the second housing element to the output disk by means of fluid friction forces.

In a further advantageous embodiment, the fluid can be made to flow through the first and second cutouts, at least in certain sections, as a result of which in particular at least one torque of the housing element can be transmitted to the output disk. In this way, at least one torque, in particular different torques, can particularly advantageously be transmitted from the housing element to the output disk.

In one advantageous embodiment, at least one knob element for holding back the viscous fluid is formed from the output disk. In this context, the viscous fluid can particularly advantageously be discharged from the torque-transmitting space.

In one advantageous development, the fan drive device has at least one storage space for storing the viscous fluid. In this way, a different rotational speed of the output disk can be particularly advantageously generated in that viscous fluid can be fed to the torque-transmitting space.

In addition, it is possible to provide that the at least one storage space rotates at least a drive speed of the belt pulley.

In this way, the storage space, which can be formed in particular in the interior of the at least one housing element, can be particularly advantageously cooled.

In one advantageous development, the valve element has a valve lever with which at least one flow duct opening of a first flow duct can be closed. In this way, the mass flow of the viscous fluid which can be admitted to the torque-transmitting space can be particularly advantageously regulated.

In addition it is possible to provide that the valve lever can be connected, in particular elastically, to the at least one housing element. The valve lever is particularly advantageously connected to the housing element.

In one advantageous embodiment, the valve lever can be pivoted about a fastening point. In this way, the valve lever can be actuated in a particularly advantageous way.

In one advantageous development, the fan drive device has at least one soft-magnetic conducting element. A magnetic flux can particularly advantageously be conducted through the at least one soft-magnetic conducting element.

In one advantageous embodiment, at least one sensor element for measuring the output speed can be arranged, in particular centrally, on a fan flange shaft. In this way, the output speed of the fan flange shaft can be measured particularly easily, for example by means of a sensor.

In one advantageous embodiment, the sensor is for measuring the output speed and/or is a Hall sensor. In this way, the output speed of the output disk and/or of the fan flange shaft can be measured particularly easily and cost-effectively.

Furthermore, it is particularly preferably possible to provide that at least one first cable for supplying power to the actuator and/or a second cable for supplying power to the sensor can be arranged or is arranged in the retaining element. In this way, the actuator and/or the sensor can particularly advantageously be supplied with power.

In one advantageous development, the first housing element and/or the second housing element have cooling fins. In this way, the fan drive device can particularly advantageously be cooled and is suitable for relatively high fan drive power levels.

In addition, it is possible to provide that the at least one impeller wheel has at least one flow-guiding element for cooling the housing element. In this way, the housing element can particularly advantageously be cooled even better, as a result of which even higher fan drive power levels can be achieved.

In a further advantageous embodiment, the impeller wheel has at least one opening for the throughflow of air and for cooling the housing element. In this way, the housing element can particularly advantageously be cooled and higher fan drive power levels can particularly advantageously be achieved.

Furthermore, it is particularly preferably possible to provide that at least one flange plate of the impeller wheel has the at least one opening for the throughflow of air and for cooling the housing element. In this way, the housing element can particularly advantageously be cooled and higher fan drive power levels can be achieved.

In one development, at least one flange plate of the impeller wheel has the at least one opening for the throughflow of air and for cooling the housing element. In this way, the housing element can particularly advantageously be cooled.

In addition it is possible to provide that at least one flange plate of the impeller wheel has the at least one opening for the throughflow of air and for cooling the housing element. In this way, the at least one housing element can particularly advantageously be cooled.

In a further advantageous embodiment, the at least one flange plate is embodied, at least in certain sections, as a flow-guiding element for cooling the housing element. In this way, the flow-guiding element can be manufactured particularly easily.

Furthermore it is particularly preferably possible to provide that the at least one flange plate is embodied, at least in certain sections, as a radial blower for cooling the housing element. In this way, the housing element can particularly advantageously be cooled.

In one development, the at least one opening is embodied as a hood for cooling the housing element. A hood is to be understood in particular as a type of inlet duct with an inlet opening or a type of inlet diffuser. In this way, the housing element can particularly advantageously be cooled.

A further advantageous embodiment is characterized in that the belt pulley has at least one belt pulley opening for cooling the housing element. In this way, the at least one housing element can particularly advantageously be cooled.

Furthermore, it is particularly preferably possible to provide that the belt pulley can be connected to the first housing element and/or to the second housing element in a positively locking fashion, in particular by screwing. In this way, the housing element can particularly advantageously be driven by the belt pulley.

In addition it is possible to provide that the output disk has at least one output disk opening for cooling at least one hub section of the output disk. In this way, the at least one hub section of the drive disk can particularly advantageously be cooled.

In one development, the fan drive device has at least one bearing for supporting the first and/or second housing element and/or the belt pulley. In this way, the first and/or second housing element and/or the belt pulley can particularly advantageously be supported.

It is also possible to provide that at least one bearing seat section of a fan shaft has at least one, in particular circumferential, cutout for cooling the output disk. In this way, the at least one bearing can particularly advantageously be cooled.

Furthermore, it is particularly preferably possible to provide that at least one bearing bushing, in particular composed of a material which is a poor conductor of heat, can be arranged or is arranged on the at least one bearing seat section of the fan shaft in order to cool the output disk. In this way, the at least one bearing can particularly advantageously be cooled.

In a further advantageous embodiment, the output disk is connected to the at least one impeller wheel. In this way, the impeller wheel can be driven in a particularly advantageous fashion.

In addition, it is possible to provide that the first drivable housing element and/or the at least second drivable housing element are mounted so as to be rotatable with respect to the retaining element.

Furthermore, it is particularly preferably possible to provide that the first drivable housing element and/or the at least second drivable housing element are mounted so as to be rotatable with respect to the drive disk.

In a further advantageous embodiment, the output disk is mounted so as to be rotatable with respect to the retaining element.

In one advantageous development, at least one belt pulley unit is designed so as to be capable of being dismounted or is dismounted from a fluid-flow-regulating unit for maintenance and/or repair purposes, and/or so as to be capable of being mounted with the fluid-flow-regulating unit, in particular after maintenance and/or repair work, and can be re-assembled with the fluid-flow-regulating unit.

Further advantageous refinements of the invention emerge from the drawings.

FIG. 1shows a slip power characteristic diagram SPCD.

In the slip power characteristic diagram SPCD the output speed OS is plotted in revolutions per minute (rpm) against the drive speed DS in revolutions per minute (rpm). In the illustrated exemplary embodiment drive speeds DS of 1,200 to 3,600 rpm and output speeds OS of 0 to 2,800 rpm are plotted. In addition, slip power curves SPC of different slip power levels are plotted in kilowatts (kW) in the slip power characteristic diagram SPCD. In the illustrated exemplary embodiment, the slip power curves for 0.75 kW, 1 kW, 1.25 kW, 1.5 kW, 1.75 kW, 2.25 kW, 2 kW, 2.5 kW, 3 kW, 3.5 kW, 4 kW, 4.5 kW, 5 kW, 5.5 kW, 6 kW, 6.5 kW, 7 kW, 7.5 kW, 8 kW and 10 kW are plotted. Intermediate values for these plotted curves can be obtained by interpolation. The slip power curve for 8 kW is denoted by way of example by SPC8.

The slip powers, which are plotted as slip power curves SPC in the slip power characteristic diagram SPCD, are produced during operation of the fan drive device on the basis of the fluid friction the at least one drivable housing element (not illustrated) transmits at least one torque to the output disk. The slip power generates heat which has to be conducted away from the fan drive device. If this heat is not conducted away from the fan drive device, inadmissibly high component temperatures of the clutch, in particular of the visco clutch, which lead or can lead to total failure of the fan drive unit, are produced.

The maximum achievable output speed MAOS is plotted in rpm against the drive speed DS as a curve. Likewise, a boundary line of the admissible slip power ASP for steady-state operation is illustrated, by way of example. This boundary line describes the heat capacity which can be dissipated for a given housing rotational speed which usually corresponds to the output speed OS. The region BUHBT, which is bounded to the left by the maximum admissible slip power curve SPC, leads to inadmissibly high component temperatures of the clutch, in particular of the visco clutch. From the diagram it is apparent that limitations on the admissible output speeds OS have to be accepted at drive speeds DS which are essentially higher than 2,350 rpm.

FIG. 2is a sectional illustration of the fan drive device1.

The fan drive device1has an impeller wheel2of a fan37, a visco clutch36, a belt pulley16and a retaining element33.

The fan37has a fan housing4, an impeller wheel2and a flange ring3. The impeller wheel2is constructed essentially from plastic. In particular, the impeller wheel2is manufactured by means of a shaping fabrication method such as injection molding, in particular plastic injection molding. The impeller wheel2has a plurality of fan blades5.

The fan37also has a fan housing4. The fan housing4is constructed essentially from plastic. The fan housing4is manufactured, or can be manufactured, in particular by means of a shaping fabrication method, such as injection molding, in particular plastic injection molding. In another exemplary embodiment, the impeller wheel2and/or the fan housing4are constructed from a material which has a low density. The material can be, for example, a composite material, in particular a fiber composite material. A flange ring3is arranged in the fan housing4. The flange ring3can be constructed from plastic or from a metal with a low density such as, for example, aluminum. In another exemplary embodiment, the fan housing4and the flange ring3are constructed in one piece. In another exemplary embodiment, the flange ring3is constructed as a simple plate. The plate can have a round shape or a rectangular shape or an oval shape or a shape which has the previously mentioned shapes. The flange ring3has at least one flange plate cutout32, in particular a plurality of flange plate cutouts32. The flange plate cutout32can have a round or oval or polygonal shape or a shape composed of the combination of the previously mentioned shapes.

At least one flow-guiding element8, in particular a plurality of flow-guiding elements8, is arranged on the fan housing4. The flow-guiding elements can be constructed from plastic or from another material such as, for example, a metal with a low density such as, for example, aluminum. The flow-guiding elements cause, in particular, air to flow in the air flow direction AFD through the flange plate cutouts32of the flange ring3and to flow past the first housing element9and/or the second housing element10, and to cool the visco clutch36, in particular the first housing element9and/or the second housing element10. In another exemplary embodiment, the at least one flow-guiding element8can be constructed in one part with the fan housing4and/or the flange ring3. The flow-guiding element is manufactured, for example, by means of a primary shaping fabrication method such as molding, in particular injection molding or by means of a shaping fabrication method such as, for example, bending or pressing.

The fan shaft6has a flange (not denoted in more detail). The fan shaft6is connected in a positively locking fashion via this flange (not denoted in more detail) to the flange ring3by means of at least one first fastening element, in particular a plurality of fastening elements7such as, for example, screws and nuts etc. A first roller bearing11, in particular a first ball bearing, in particular a two-row ball bearing, is arranged on the fan shaft6. The inner bearing ring (not denoted in more detail) of the first roller bearing11is connected to the fan shaft6by means of a press fit.

In addition, the output disk13is arranged on the fan shaft6. The fan shaft6has a bore (not denoted in more detail) via which the output disk13can be pushed onto the fan shaft6. The output disk13can be connected to the fan shaft6by means of a press fit. In another exemplary embodiment, the output disk13is connected to the fan shaft6in a positively locking fashion. The fan shaft6is constructed from steel but it can also be constructed from aluminum or from a fiber composite material.

The output disk13is constructed from steel. In addition, the output disk13can also be constructed from a fiber composite material or from ceramic. The output disk13has concentric labyrinthine cutouts (not denoted in more detail). The cutouts are formed in the output disk13using, for example, a material-removing fabrication method such as turning, milling, grinding etc. In another exemplary embodiment, the concentric labyrinthine cutouts can be formed in the output disk13by means of a blasting method such as, for example, by means of a laser beam or by means of a shaping fabrication method or by means of a primary shaping fabrication method. The cutouts are arranged extending radially inward in a part of the output disk13(not designated in more detail) from the outermost radius of the output disk as far as an inner radian section. In section the part in which the labyrinthine cutouts are arranged has a shape like a trunk of a tree, extending from which a plurality of branches are arranged on the left and right of the trunk essentially at an angle of 90° with respect to the trunk.

The output disk13has a first flow duct18. The flow duct18is embodied in such a way that a first bore runs in a radial direction of the output disk from radially on the outside toward the inside as far as a certain inner radius. For this purpose, a second bore is arranged essentially perpendicularly. The second bore is arranged at the level of the inner radius of the output disk. A ram pressure is generated from the visco clutch36by means of a knob (not illustrated), with the effect that fluid, in particular viscous fluid such as, for example, silicone oil, flows counter to the centrifugal force through the flow duct18into a storage space20of the visco clutch36or of the first housing element.

A housing (not denoted in more detail) with a first housing element9and a second housing element10is arranged around the output disk13. The first housing element9and the second housing element10are connected to one another in a positively locking fashion by means of at least one second fastening element21, in particular a plurality of second fastening elements21. In another exemplary embodiment, the first housing element9and the second housing element10are connected to one another in a materially joined fashion, for example by soldering, bonding, welding etc. In another exemplary embodiment, the first housing element9and the second housing element10are embodied in one piece. In another exemplary embodiment, the housing elements9,10are formed around the output disk13by primary shaping.

The first housing element9has a bore (not denoted in more detail) into which the first roller bearing11is pushed or pressed. The first housing element9has a part with labyrinthine concentric cutouts (not denoted in more detail) which correspond essentially to the labyrinthine concentric cutouts (not denoted in more detail) of the output disk13.

The second housing element10also has, at least in certain sections, labyrinthine concentric cutouts which correspond essentially to the labyrinthine concentric cutouts (not denoted in more detail) of the output disk13. The concentric labyrinthine cutouts are formed in the first housing element9and/or the second housing element10by means of a material-removing fabrication method such as, for example, turning, milling, grinding etc. In another exemplary embodiment, the labyrinthine concentric cutouts are formed in the first housing element9and/or in the second housing element10by means of a laser beam or by means of a primary shaping fabrication method such as, for example, molding or injection molding or by means of a shaping fabrication method such as, for example, pressing.

The first housing element9and/or the second housing element10are constructed from a metal such as, for example, steel or aluminum or from another lightweight metal. In particular, the first housing element9and/or the second housing element10are manufactured by means of a primary shaping fabrication method such as, for example, molding, in particular injection molding, in particular metal injection molding. In the illustrated exemplary embodiment, at least one bore19, in particular two bores19, are formed in the second housing element10. The bores have an angle (not denoted) of 5° to 6°, in particular 10° to 50°, in particular 15° to 47°, in particular 20° to 45°, in particular 30° to 45°. Viscous fluid, in particular silicone oil, is introduced into the torque-transmitting space15via the bore19or the two bores by virtue of the centrifugal force and it flows into the torque-transmitting space15.

A storage space20is formed in the second housing element10. The storage space20is bounded, at least in certain sections, by a storage space disk29and a wall section (not denoted in more detail) of the second housing element10. On the second housing element10, a valve lever disk of a valve lever (not denoted in more detail) is connected in a rotatable fashion to the second housing element10via a fastening point31. In particular, the valve lever disk30can carry out a pivoting movement about the fastening point31. During the pivoting movement, the bore19is cleared, at least in certain sections. There are three possible positions of the valve lever disk30here. In one position1, the bore19is closed so that no viscous fluid, in particular silicone oil, can enter the bore19from the storage space20. If the valve lever disk30is in position2, the bore19has a fluidic connection, at least in certain sections, to the storage space20, with the result that fluid, in particular viscous fluid, such as silicone oil, can flow into the bore19. If the valve lever disk30is in position3, an opening (not denoted in more detail) of the bore19is completely cleared, with the result that viscous fluid, in particular silicone oil, can enter the bore19.

The valve lever disk30is connected in a materially joined and/or positively locking fashion to an armature38. The armature38can be actuated, or is actuated, by means of the actuator26or the solenoid27. When the armature38is activated by the actuator26or the solenoid27it carries out, in particular, a rotational movement which is transmitted to the valve lever disk30. The valve lever disk30and the armature38have at least one bore (not denoted in more detail) through which a sensor24, in particular a rotational-speed-measuring sensor and/or a temperature-measuring sensor, is plugged. The second housing element10has at least one threaded bore, in particular a number of threaded bores, into which fastening elements22, in particular third fastening elements such as, for example, screws are screwed. In this way the belt pulley16, which can be driven with a belt (not illustrated), is connected to the second housing element10, in particular in a positively locking or materially joined fashion. In another exemplary embodiment, the belt pulley16is connected to the first housing element9. In another exemplary embodiment, the belt pulley16is embodied in one piece with the second housing element10and/or the first housing element9.

The belt pulley16has at least one belt pulley opening17, in particular a number of belt pulley openings17. Air can flow through the belt pulley openings17when the belt pulley16turns or rotates, and said air cools the second housing element10and/or the first housing element9. The belt pulley16has a bore (not denoted in more detail) which is arranged, in particular, in the center of the belt pulley. This bore forms a hub section (not denoted in more detail). In the hub section (not denoted in more detail), a second roller bearing23, in particular a ball bearing, in particular a two-row ball bearing, is formed or arranged. The second roller bearing23is connected in a frictionally locking fashion to the belt pulley16, in particular by means of an interference fit assembly. However, in the illustrated exemplary embodiment, the pairing of the second roller bearing23to the belt pulley16is embodied as play or a transition fit and the inner bearing ring (not denoted in more detail) is held with a nut (not denoted in more detail), wherein the outer ring of the second roller bearing23is embodied as a loose bearing, with the result that the outer bearing ring of the second roller bearing23can expand freely when heating occurs.

The inner bearing ring of the second roller bearing23is arranged on a retaining element33, in particular on a flange. A shaft (not denoted in more detail) is formed, at least in certain sections, from the flange33. The shaft has a first shaft shoulder (not denoted in more detail) and at least a second shaft shoulder (not denoted in more detail). The second roller bearing23is pushed onto the shaft section with the inner bearing ring (not denoted in more detail) as far as the second shaft shoulder (not denoted in more detail). The inner bearing ring is in contact, at least in certain sections, with the second shaft shoulder (not denoted in more detail). The inner bearing ring (not denoted in more detail) of the second roller bearing23is fastened on the shaft section of the retaining element33, in particular of the flange, with a bearing securing means (not denoted in more detail), in particular a screw.

The retaining element33has at least one bore34, in particular a plurality of bores34. The retaining element, in particular the flange, is screwed onto, or connected to an engine unit (not illustrated) through the at least one bore34, in particular through the plurality of bores34, by means of fastening elements (not illustrated) such as, for example, screws on the motor unit (not illustrated). The retaining element shaft section39is formed from the retaining element33, in particular from the flange. The retaining element33or the retaining element shaft section39has a cavity35, in particular a bore. The retaining element shaft section39has, in the interior, a step (not denoted in more detail) which is embodied as a shoulder, in particular in a circumferential fashion. The cavity35of the retaining element33, in particular the retaining element shaft section39, has a first bore (not denoted in more detail) which has a larger diameter than a second bore (not denoted in more detail). The first bore (not denoted in more detail) is embodied essentially in the form of a cylinder. The second bore (not denoted in more detail) is also embodied in the form of a cylinder. The actuator26, or respectively the solenoid27, is arranged in the second bore (not denoted in more detail). The actuator26and solenoid27are embodied in such a way that they are in contact, at least in certain sections, with the bore. The actuator26and the solenoid27are embodied essentially in the form of a cylinder, with the result that they can be pushed, or are pushed, into the second bore (not denoted in more detail). In another exemplary embodiment, the actuator26and the solenoid27can be embodied in the form of a parallelepiped.

In addition, in the illustrated exemplary embodiment, a sensor24is arranged in the cavity35of the retaining element33or respectively of the retaining element shaft section39. In the illustrated exemplary embodiment, the sensor24is a sensor for measuring rotational speed. In another exemplary embodiment, the sensor24can, however, also be a temperature sensor for measuring the temperature. The sensor24is arranged essentially concentrically with respect to the cavity35of the retaining element33or with respect to the cavity35of the retaining element shaft section39. In another exemplary embodiment, the sensor34can also be arranged outside the center, wherein the center is to be considered essentially to be the axis of the second bore (not denoted in more detail) of the cavity35. In the illustrated exemplary embodiment, the actuator26and the solenoid27have an axially symmetrical, essentially concentric bore in which the sensor24is arranged. In another exemplary embodiment (not illustrated), the sensor24is not arranged concentrically and axially symmetrically in the actuator26or respectively the solenoid27but rather is arranged outside the axis of the actuator26or of the solenoid27. The at least one actuator cable28, which is used, in particular, to supply power to the actuator26or respectively to the solenoid27, is led away outwards from the cavity35of the retaining element33, in particular of the flange or respectively of the holding element shaft section39, from the retaining element33, in particular of the flange. In addition, at least one sensor cable25of the sensor24, in particular of the rotational speed sensor, is led outwards from the cavity35of the retaining element33, in particular of the flange, or respectively of the retaining element shaft section39. The sensor cable25serves essentially to supply power to the sensor24. The at least one sensor cable25and the at least one actuator cable28have a common cable duct in which they are essentially arranged.

The retaining element33, in particular the flange, is arranged in an essentially rotationally fixed fashion. The belt pulley16carries out a rotational movement about the axial direction AD when it is driven by means of a belt (not designated in more detail or illustrated).

In addition, the at least one first housing element9and/or the at least one second housing element10carries out a rotational movement about the axial direction AD when the belt pulley16is driven. The belt pulley16and the at least one first housing element9and/or the at least one second housing element10have identical circumferential speeds.

The drive disk13can also rotate about the axial direction AD. The output disk13rotates, in particular, about the axial direction AD, if at least one torque is transmitted from the at least one first housing element9and/or the at least one second housing element10to the output disk13by means of fluid friction of the viscous fluid, in particular of the silicone oil. Owing to the slip, the output disk13usually has a lower circumferential speed than the belt pulley16or the first housing element9and/or the second housing element10. If the drive disk16is not driven and consequently the circumferential speed is 0 m/sec, the first housing element9or the second housing element10also has the circumferential speed 0 m/sec. In the illustrated exemplary embodiment, the output disk13is permanently connected to the impeller wheel2, with the result that the circumferential speed of the impeller wheel2corresponds at all times to the circumferential speed of the output disk13.

In the operating state, the belt pulley16is driven at a drive speed. This drive speed is transmitted to the first housing element9and/or the second housing element10by virtue of the positively locking connection between the belt pulley16and the first housing element9and/or the second housing element10. The first housing element9and/or the second housing element10are cooled owing to the rotational movement during operation and owing to the fins, in particular cooling fins, which are provided. In the illustrated exemplary embodiment, the belt pulley16is arranged in a rotatable fashion on the retaining element33, in particular the flange. In another exemplary embodiment, the at least one housing element9and/or the second housing element10can be arranged in a rotatable fashion on the retaining element33, in particular the flange. In the illustrated exemplary embodiment, the first housing element9is arranged in such a way that it can rotate with respect to the fan shaft6. The fan shaft6essentially is the output. In another exemplary embodiment (not illustrated), the fan shaft6is arranged and/or mounted in such a way that it can rotate with respect to the retaining element33, in particular the flange. The sensor24may be, for example, a Hall sensor. The at least one first housing element9and/or the at least one second housing element10have radially extending cooling fins. In another exemplary embodiment, the cooling fins extend vertically or horizontally with respect to the axial direction AD. In addition, the cooling fins can be arranged at an angle between 0° and 90°, in particular between 15° and 80°, in particular between 25° and 70°, in particular between 30° and 60°, in particular between 40° and 50°.

The driving of the at least one first housing element9and/or of the at least one second housing element10by the belt pulley16results in a greater throughflow through the fins and cooling fins (not denoted in more detail) since the air for cooling flows from the inside to the outside owing to the centrifugal force. This cooling effect is improved by the flow-guiding element8, in particular by the air-guiding element, which causes the air to be sucked in the inner diameter region of the cooling fins of the first housing element9. The flow profile of the air is improved further by the belt pulley opening17.

FIG. 3shows a sectional illustration of a further embodiment of a fan drive unit50. Identical features are provided with the same reference signs as in the previous figures.

In contrast to the fan device1inFIG. 2, the retaining element51is of a different design. The retaining element51is, in particular, a flange. The retaining element51, in particular the flange, has a retaining element shaft section54which is formed from the retaining element51. The retaining element51is formed from steel or from another metal. In particular, the retaining element51is manufactured by means of a primary shaping fabrication method such as, for example, molding. The retaining element51has at least one bore52, in particular a plurality of bores52, into which fastening elements such as, for example, screws, can be plugged, and with which the retaining element51can be connected, in particular connected in a positively locking fashion, to an engine unit (not illustrated).

The retaining element shaft section54of the retaining element51, in particular of the flange, is embodied in certain sections as a solid shaft, and in certain adjoining sections as a hollow shaft. In the section which is embodied as a solid shaft, a bore52is provided in the retaining element. In the illustrated exemplary embodiment, the bore52is arranged centrally in the axial direction AD. The sensor24is arranged in the bore52, which is embodied essentially in the form of a cylinder. The bore52is essentially of such a size that it accommodates the entirety of the sensor24essentially in the radial direction with respect to the axial direction AD. In contrast toFIG. 2, the actuator56or respectively the solenoid57is arranged on the outside of the retaining element shaft section54. The actuator56and the solenoid57have a bore which is of concentric design. The bore (not denoted in more detail) of the actuator56or respectively of the solenoid57is essentially embodied in the form of a cylinder. The bore has essentially the same diameter (not denoted in more detail) as a section (not denoted in more detail) of the retaining shaft element section54. The retaining element shaft section54is adjusted especially to the same diameter as the bore of the actuator56or respectively of the solenoid57using, for example, a material-removing fabrication method such as turning, milling, grinding etc.

The retaining element51, in particular the flange, has a cavity53through which the actuator cable28and/or the sensor cable25are connected to the power supply in a cable duct55.

The axially offset arrangement of the roller bearing23and of the actuator56or respectively of the solenoid57permits free dimensioning of the bearing23and of the solenoid. In particular the bearing23can be fabricated with relatively small internal and external diameters in an easier and more cost-effective way.

FIG. 4is a sectional illustration of a further embodiment of a fan drive unit70. Identical features have been provided with the same reference signs as in the previous figures.

In contrast toFIG. 2, the flow-guiding element8in this embodiment is integrated as a flow-guiding element73, in particular as an air-guiding element, into the fan housing plate72. The fan housing71has at least one fan housing plate72. The fan housing71is essentially embodied in the same way as the fan housing4inFIG. 2. The fan housing plate is constructed from plastic or from a metal, in particular with a low density. For example, the fan housing plate72can be constructed from aluminum or else from steel. In addition, the fan housing plate72can be constructed from a fiber composite material. The fan housing plate72has at least one flow-guiding element73and is embodied in particular in one piece therewith. The fan housing plate72is manufactured, for example, by means of a primary shaping fabrication method such as molding. The housing plate72can also be manufactured by means of a shaping fabrication method such as, for example, pressing, punching etc. In particular, the flow-guiding element73, in particular the air-guiding element, is formed in the fan housing plate72by means of a primary shaping or shaping fabrication method such as, for example, stamping or punching etc.

FIG. 5is an isometric illustration of a fan drive device80, of a fan81and of an impeller wheel82. Identical features have been provided with the same reference signs as in the previous figures.

The fan drive device80which is illustrated inFIG. 50has a fan81with an impeller wheel82.

In the illustrated exemplary embodiment, the impeller wheel82has eleven impeller wheel blades83. In another exemplary embodiment, the impeller wheel82can have one to eleven or more than eleven impeller wheel blades83. In addition, the impeller wheel82has flow-guiding elements (not denoted in more detail) which are arranged on the impeller wheel blades83and are embodied in one piece with the impeller wheel blades83. The impeller wheel82also has an impeller wheel hub84.

FIG. 6shows a detail illustration A of a fan drive device80of a fan81and of an impeller wheel82.

Identical features are provided with the same reference signs as in the previous figures.

The impeller wheel82has a number of impeller wheel blades83. In the illustrated exemplary embodiment, the impeller wheel blades83are embodied in one piece with the impeller wheel hub84. In another exemplary embodiment, the impeller wheel blades83are connected to the impeller wheel hub84in a materially joined fashion, in particular by welding, soldering, bonding etc., and/or in a positively locking fashion. In the illustrated exemplary embodiment, the impeller wheel82has twelve impeller wheel blades83. In another exemplary embodiment, the impeller wheel82has one to twelve impeller wheel blades83or more than twelve impeller wheel blades83. In the illustrated exemplary embodiment, the impeller wheel or the fan81carries out a rotational movement in the direction of the impeller wheel rotational direction IWRD. Air inlet ducts88are formed in the impeller wheel hub84. In the illustrated exemplary embodiment, six air inlet ducts88are formed in the impeller wheel hub. In another exemplary embodiment, one to six or more than six impeller wheel inlet ducts88are formed from the hub. In the illustrated exemplary embodiment, the at least one air inlet duct, in particular the six air inlet ducts, are formed in one piece with the impeller wheel hub84. In another exemplary embodiment, the impeller wheel hub84has openings (not illustrated). In the section of the openings (not illustrated), the air inlet ducts88are connected to the impeller wheel hub84in a materially joined fashion, in particular by welding, soldering, bonding etc., and/or in a positively locking fashion.

The air inlet ducts88are formed essentially as an inlet diffuser. The at least one air inlet duct88has at least one air inlet duct opening89. In the illustrated exemplary embodiment, the air inlet duct opening89is of rectangular design. In another exemplary embodiment (not illustrated), the air inlet duct opening89is round or oval or embodied as a combination of a round, oval or polygonal shape. Adjacent to the air inlet duct openings89, a hub ring87is arranged essentially concentrically with respect to the axial direction AD. In the illustrated exemplary embodiment, the hub ring87is embodied in one piece with the fan81or the impeller wheel82. In another exemplary embodiment, the hub ring87can be connected to the impeller wheel82in a positively locking or materially joined fashion, in particular by welding, soldering, bonding etc. In the illustrated exemplary embodiment, the hub ring87is formed from a metal such as, for example, stainless steel or some other steel or from aluminum. In another exemplary embodiment, the hub ring87can be formed from plastic or from a fiber composite material. In the illustrated exemplary embodiment, the hub ring87has six hub bores86, one hub bore86of which is covered by an air inlet duct88in the isometric illustration. In another exemplary embodiment, the hub ring87has one to six hub bores86or more than six hub bores86. In another exemplary embodiment, the hub ring composed of metal is formed in the impeller wheel82during the primary shaping process, in particular during the injection molding, for example during the plastic injection molding, in such a way that the plastic is injected, at least in certain sections, around the hub ring87, with the result that the hub ring87is essentially permanently connected to the impeller wheel82after the plastic cools. In the illustrated exemplary embodiment, the air inlet ducts88are constructed from plastic. In another exemplary embodiment, the air inlet ducts88are constructed from another material with a low density such as, for example, from a metal with a low density such as, for example, from aluminum or from a fiber composite material.

If the impeller wheel82rotates in the direction of the impeller wheel rotational direction IWRD about the axial direction AD, air is fed in the direction of the air flow AFD through the air inlet duct opening89in the direction of the first housing element9(not illustrated) and/or of the second housing element10, wherein the at least one first housing element9and/or the at least one second housing element10are cooled. The at least one hub bore86, in particular the six hub bores86, are used to fasten the fan81or the impeller wheel82in a positively locking fashion to the impeller shaft6(not illustrated). The air inlet ducts88form a radial blower, in which case the cooling fins (not illustrated) of the first housing element9and/or of the second housing element10form a type of vane. This ensures that the cooling air leaves the cooling fins (not illustrated) of the first housing element9at the outermost circumference and a favorable flow profile is produced. The air inlet ducts88can also be referred to as scoops. A plurality of the air inlet ducts88, in particular the scoops, are arranged on the circumference of the hub bore86of the impeller wheel82, resulting in an axial vane effect in combination with a retaining effect as a result of the rotation of the fan. This improves the sucking in of cooling air of the cooling fins of the first housing element9, said cooling fins operating according to the principle of a radial fan. At the same time, the solid material cross section in this region of the impeller wheel hub84is retained, in contrast to simple axial openings, which is necessary for the transmission of mechanical forces of the fan81. As a result of the box-shaped construction of the air inlet ducts88, in particular of the scoops, the mechanical rigidity of the impeller wheel hub84, in particular of the fan flange plate (not denoted in more detail) can be increased in the hub ring section of the hub ring87. The hub ring87, in particular the fan flange plate, can be fabricated as a shaped part composed of sheet metal. In another exemplary embodiment, the impeller wheel hub84, in particular the fan flange plate, can be embodied as a cast part, in particular composed of cast lightweight metal. In the construction of the impeller wheel hub84from cast lightweight metal, the geometric freedom of configuration is greater. The properties of the feeding of the cooling air and of the mechanical strength can then be increased even further.

FIG. 7shows a sectional illustration of a further exemplary embodiment of a fan drive unit100. Identical features have been provided with the same reference signs as in the previous figures.

In contrast to the preceding exemplary embodiments, in the fan drive device100, the actuator101or the solenoid102are arranged further behind in the retaining element shaft section54. The cavity53accommodates the actuator101or respectively the solenoid102, at least in certain sections. An actuator cover plate103for covering the actuator101or respectively the solenoid102has an opening (not denoted in more detail) from which the sensor cable (not denoted in more detail) and/or actuator cable of the actuator101or of the solenoid102is led out from the retaining element shaft section54and connected to the power supply (not illustrated). In this way, the actuator101or the solenoid102is subjected to less thermal loading, and the bearing23can be dimensioned more freely.

FIG. 8is a sectional illustration of a further embodiment of a fan drive unit120. Identical features have been provided with the same reference signs as in the previous figures.

In contrast to the previous figures, the belt pulley123is embodied as a belt pulley ring126. The belt pulley ring126has an opening (not designated in more detail). In addition, the second housing element122has at least one threaded bore125, in particular a plurality of threaded bores125. The first housing element121also has at least one bore, which is not denoted in more detail. By means of a connecting element124, in particular by means of a screw, the at least one belt pulley ring126, the first housing element121and the second housing element122are connected to one another in a positively locking fashion, in particular by screwing.

The bearing23is arranged, at least in certain sections, in the second housing element122. This arrangement of the roller bearing23is particularly advantageous with respect to the conduction away of heat from the second housing element122and with respect to the costs and the weight of the second housing element. However, the diameter of the belt pulley123and of the belt pulley ring126must be dimensioned so that it is sufficiently large in relation to the diameter of the first housing element12and/or of the second housing element122.

In another exemplary embodiment (not illustrated), the belt pulley123, or respectively the belt pulley ring126, is constructed in one piece with the first housing element121and/or in one piece with the second housing element122. The first housing element121and/or the second housing element122are then correspondingly embodied as a belt pulley123or respectively as a belt pulley ring126.

FIG. 9is a sectional illustration of a fan drive unit140with a coolant pump drive unit141. Identical features have been provided with the same reference signs as in the previous figures.

In contrast to the previous figures, the belt pulley146is used to drive both the fan drive unit140and simultaneously a coolant pump drive unit141.

The fluid friction clutch (not denoted in more detail), in particular the visco clutch, has a first housing element143. In addition, the fluid friction clutch has a second housing element145. The first housing element143is sealed with respect to the second housing element145by means of a sealing element144, in particular an O ring. The first housing element143and the second housing element145are connected in a positively locking and/or materially joined fashion, in particular by means of a screw/nut connection. The first housing element143has labyrinthine cutouts155. The at least one output disk142has corresponding labyrinthine cutouts155. By means of a viscous fluid (not denoted in more detail), in particular by means of silicone oil, at least one torque is transmitted from at least the one first housing element143to the output disk142by means of fluid friction. The output disk142is mounted on the fan shaft6, or is connected to the fan shaft6, in a positively locking and/or frictionally locking fashion. In addition, a first bearing151is arranged on the fan shaft6and in a section (not denoted in more detail) of the first housing element143.

The first bearing151is a roller bearing, in particular a single-row grooved ball bearing. By means of the first bearing151, the first housing element143, which is driven with a drive speed or rotates with a drive circumferential speed, is mounted in such a way that it can rotate with respect to the relatively low output speed of the fan shaft6.

The belt pulley146is driven by a belt (not illustrated in more detail). The belt pulley146is embodied in such a way that it conducts magnetic flux. The belt pulley146is connected to the second housing element145in a positively locking and/or materially joined fashion. The second housing element145is connected to the magnetically conductive hub157in a positively locking and/or materially joined fashion. The belt pulley146is embodied in such a way that it conducts magnetic flux, i.e. it is constructed from a material which conducts the magnetic flux or is magnetizable. The magnetically conductive hub157is connected to a coolant pump shaft150in a frictionally locking fashion. In particular, the magnetically conductive hub157is shrink-fitted onto the coolant pump shaft150. The coolant pump shaft150has, at least in certain sections, a significant, circumferential cutout, in particular a groove, which is embodied as a bearing section. In the region of the bearing section (not denoted in more detail) a second bearing152is arranged. The second bearing152is embodied essentially as a roller bearing, in particular as a single-row grooved ball bearing. The coolant pump shaft150is connected to the coolant pump housing149in such a way that it can rotate by means of the second bearing152, or is mounted in such a way that it can rotate with respect to the rotationally fixed coolant pump housing149. The outer bearing ring (not denoted in more detail) of the second bearing152is connected in a positively locking fashion to the coolant pump housing149via a shaft securing ring (not denoted). The outer bearing ring (not denoted in more detail) bears, at least in certain sections, on a shoulder (not denoted in more detail) of the coolant pump housing149. In addition, at least one shaft sealing ring153is provided on the shaft. The shaft sealing ring153prevents, in particular, bearing oil from escaping outwards from the bearing153.

The coolant pump shaft150is used to drive a coolant pump156. An actuator147or a solenoid148is arranged on the coolant pump housing149, on a coolant pump housing section which is not denoted in more detail. The actuator147or the solenoid148is pushed onto the coolant pump housing149as far as a shoulder (not denoted in more detail) of the coolant pump housing149. The actuator147or the solenoid148is arranged in a rotationally fixed fashion, in particular on the coolant pump housing149.

The belt pulley146, the second housing element145and the hub147are capable of conducting magnetic flux or are magnetically conductive, i.e. they can be magnetized or they conduct the magnetic flux. The magnetically conductive hub157is connected to a magnetic armature159. The magnetic armature159is connected to a valve element158, in particular to a valve lever. The valve element158, in particular the valve lever, closes and/or opens a bore or opening in the bore19(not denoted in more detail).

In another exemplary embodiment, the magnetic-flux-conducting belt pulley146is constructed in one piece with the second housing element145.

The coolant pump156is a water pump in the illustrated exemplary embodiment.

The second housing element145is constructed in such a way that it is magnetically non-conductive in the illustrated exemplary embodiment, in particular it is constructed from a material which is not magnetically conductive and which therefore serves to provide magnetic insulation between the at least two hubs157and the belt pulley156.

FIG. 10is a sectional illustration of a further embodiment of a fan drive unit170with a bearing bushing171. Identical features have been provided with the same reference symbols as in the previous figures.

In contrast to the previous embodiments, the fan shaft6has a fan shaft bearing section174. The fan shaft bearing section174is provided circumferentially in the fan shaft6. The fan shaft bearing section174is provided in the fan shaft6by means of a material-removing fabrication method, in particular by means of grinding. The bearing bushing171is pushed, at least in certain sections, onto the fan shaft bearing section174and is in contact with it, at least in certain sections. The bearing bushing171is pushed on as far as a shaft shoulder173of the fan shaft6and is in contact with it at least in certain sections. In addition, the bearing bushing171is in contact with the inner ring of the roller bearing11, in particular of the two-row grooved ball bearing, at least in certain sections. The bearing bushing171has a bearing bushing collar172, which engages around the bearing11, in particular the inner ring of the bearing11.

Since the output disk13does not have any direct contact with the outer surroundings, its thermal loading is relatively high. Apart from via the viscous fluid, in particular the silicone oil, the output disk13can only conduct heat away to the surroundings via the fan shaft6. In this context, the inner ring (not denoted in more detail) of the bearing11is subjected to high thermal loading. In particular, the service life of the bearing grease decreases greatly as the temperature rises so that any reduction in the bearing temperature leads to an extension of the service life of the bearing grease and/or of the bearing. For this reason, the bearing bushing171is constructed from a material which is a poor conductor of heat. The bearing bushing171is constructed, for example, from plastic. In addition, the bearing bushing171can also be constructed from ceramic or a fiber composite material.

FIG. 11is a sectional illustration of a further embodiment of a fan drive unit180with a circumferential cutout in the bearing seat182, which is embodied as a groove183. Identical features have been provided with the same reference signs as in the previous figures.

In contrast to the previous figures, the fan shaft6has a fan shaft bearing section181in which a cutout182is provided. The cutout182is embodied as a groove, in particular as a circumferential groove. The groove183reduces the area of the fan shaft6over which heat can be transmitted to the bearing inner ring (not denoted in more detail) of the bearing11.

FIG. 12is a sectional illustration of a further embodiment of a fan drive unit200with a belt pulley unit203which can be dismounted from a fluid-flow-regulating unit202. Identical features have been provided with the same reference symbols as in the previous figures.

The fluid-flow-regulating unit202can correspond, for example, to the valve lever disk30. The flow of fluid, for example of silicone oil, which can flow into the bore19is regulated by means of the fluid-flow-regulating unit202. The belt pulley unit203has at least the belt pulley16, at least a bearing23, the actuator26, the sensor24and the retaining element33.

For example for service purposes, the belt pulley unit203can be dismounted or separated from the fluid-flow-regulating unit202. For example in the case of a defect in the belt of the vehicle it may be useful, when changing the belt, if the fluid-flow-regulating unit202can be released from the belt pulley unit, dismounted and mounted again without the fluid, in particular oil such as silicone oil, running out of the fluid-flow-regulating unit202or without other changes occurring. In the event of damage, for example in the event of an accident, both the fluid-flow-regulating unit202and the belt pulley unit203can be replaced independently of one another.

The dismounting and/or separation of the fluid-flow-regulating unit202from the belt pulley unit203is done by unscrewing the third fastening elements22, in particular screws. This is made possible by an oil-tight closure of the fluid-flow-regulating unit202, which is formed, for example, by a closure capsule201which is connected to the second housing element10, in particular in a materially joined and/or positively locking fashion. The closure capsule201can also be inserted into the housing element10. The closure capsule201is constructed with thin walls composed of a magnetically non-conducting material such as, for example, plastic. Owing to the small wall thickness, the closure capsule201permits magnetic fields to pass through both to activate the magnetic armature and to activate the sensor24. The closure capsule201can also be formed by a thin-walled embodiment of the housing element10.

The features of the various exemplary embodiments can be combined with one another as desired. The invention can also be used for fields other than those indicated.