Wheel hub drive for a motor vehicle

Abstract

The invention relates to a wheel hub drive for a motor vehicle, comprising an electric machine having a stator and a rotor, a drive shaft (10) arranged coaxially to the rotor, drivable by the rotor, and thus rotatable about a rotational axis (26) relative to the stator, a vehicle wheel arranged coaxially to the rotor and coaxially to the drive shaft (10), drivable by the drive shaft (10), and thus rotatable about the rotational axis (26) relative to the stator, a planetary gear (12) via which the drive shaft (10) can be driven by the rotor, and an oil distribution element (20) designed as a pot-shaped cover element, which closes off an oil chamber (22) of the wheel hub drive through which oil can flow, in a direction extending in the axial direction of the rotor and pointing away from the vehicle wheel, and which has a feed part (30) protruding from a base region (28) of the oil distribution element (20).

Description

[0001] The invention relates to a wheel hub drive for a motor vehicle, in particular for a motor vehicle.

[0002] JP 2013-147217 A discloses a wheel hub motor drive unit in which, during operation of the electric motor, the oil stored in the lower part of the housing is stripped off by the rotation of the rotor. The stripped off oil flows through axially spaced, opposing sections of an internal gearing into a first and a second planetary gear.

[0003] JP 2013 - 135 531 A discloses a brake device with a wheel hub motor, in which a lubricant and coolant for self-lubrication and cooling of the permanent magnet synchronous motor is provided in a housing, wherein a lubricant and coolant is arranged in a housing that accommodates the permanent magnet synchronous motor.

[0004] JP 2013-071 686 A discloses a wheel hub motor drive unit which absorbs relative displacement and absorbs such lateral forces and displacements of the wheel hub so that they do not reach a gear set in the wheel hub motor drive unit.

[0005] The CN 221 221 377 U is known to contain a reduction gear cover plate, a reduction gear rear shell, a reduction gear and an engine assembly for vehicles with alternative drive type.

[0006] DE 10 2021 202 837 A1 discloses a drive arrangement for a motor vehicle, comprising a housing with an engine compartment and a transmission compartment adjacent to the engine compartment and separated from it by an inner bulkhead.

[0007] The object of the present invention is to provide a wheel hub drive for a motor vehicle, so that a supply of at least one region of the wheel hub drive with a lubricant can be realized in a particularly advantageous manner.

[0008] This object is achieved by a wheel hub drive having the features of patent claim 1. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0009] The invention relates to a wheel hub drive, also referred to as a wheel hub drive device or wheel hub drive unit, for a motor vehicle, also simply referred to as a vehicle, which is preferably designed as a motor vehicle, in particular as a passenger car. This means that the motor vehicle, in its fully manufactured state, has the wheel hub drive and can be driven by means of the wheel hub drive, in particular purely electrically. As will be explained in more detail below, the wheel hub drive is an electric wheel hub drive, by means of which the motor vehicle can be driven, in particular purely electrically. For example, in its fully manufactured state, the motor vehicle has at least or exactly two vehicle axles, which are arranged one behind the other and thus consecutively in the longitudinal direction of the motor vehicle and are also simply referred to as axles.The respective vehicle axle of the motor vehicle has at least or exactly two respective vehicle wheels, also simply referred to as wheels, wherein the vehicle wheels of the respective vehicle axle are arranged on opposite sides of the motor vehicle in the transverse direction of the vehicle. The vehicle wheels of the motor vehicle are ground contact elements by means of which the motor vehicle can be or is supported downwards on a ground in the vertical direction of the motor vehicle. If the motor vehicle, whose interior, also referred to as the passenger cell or passenger compartment or cabin, is formed, for example, by a motor vehicle structure designed in particular as a self-supporting body, is driven along the ground while the motor vehicle is supported downwards on the ground in the vertical direction of the motor vehicle via the ground contact elements, the ground contact elements roll, in particular directly, on the ground.The wheel hub drive is also referred to as the first wheel hub drive. When reference is made above and below to the wheel hub drive, this refers, unless otherwise stated, to the first wheel hub drive. The wheel hub drive comprises, in particular, a first of the vehicle wheels of one of the vehicle axles. When reference is made above and below to the vehicle wheel, this refers, unless otherwise stated, to the first vehicle wheel. Thus, the first vehicle wheel can be driven, in particular purely electrically, by means of the electric wheel hub drive.For example, in its fully manufactured state, the motor vehicle has a second wheel hub drive provided in addition to the first wheel hub drive, by means of which, in particular precisely, a second of the vehicle wheels of the motor vehicle can be driven, in particular purely electrically. It is conceivable that the second wheel hub drive comprises the second vehicle wheel. Preferably, the first vehicle wheel and the second vehicle wheel are the vehicle wheels of the same vehicle axle. The previous and following statements regarding the first wheel hub drive and the first vehicle wheel can readily be applied to the second wheel hub drive and the second vehicle wheel, and vice versa.

[0010] The wheel hub drive comprises an electric machine by means of which the vehicle wheel can be driven, in particular purely electrically. The electric machine is preferably designed as an axial flux machine, also referred to as an axial flux motor (AFM). The electric machine comprises a stator and a rotor, which can be driven by the stator and is thus rotatable about a machine rotation axis relative to the stator. In particular, the electric machine can provide drive torques via its rotor for driving the vehicle wheel, in particular purely electrically.

[0011] The wheel hub drive also has a drive shaft arranged coaxially to the rotor, drivable by the rotor, and thus rotatable relative to the stator about a shaft rotation axis, also simply referred to as the rotation axis. Because the drive shaft is arranged coaxially to the rotor, the drive shaft rotation axis coincides with the machine rotation axis. For example, the drive shaft is a wheel hub, or the drive shaft is also referred to as a wheel hub. Furthermore, it is conceivable to provide a wheel hub, which is designed in particular separately from the drive shaft, arranged coaxially to the drive shaft, and, in particular permanently, non-rotatably connected to the drive shaft, which wheel hub can be driven by the drive shaft, such that the vehicle wheel can be driven by the drive shaft via the wheel hub.For example, the drive shaft is rotatably mounted on a wheel carrier of the wheel hub drive, so that the drive shaft is rotatably mounted on the wheel carrier about the rotational axis relative to the wheel carrier. In particular, the drive shaft is rotatably mounted on the wheel carrier via a radial bearing.

[0012] The vehicle wheel is arranged coaxially to the rotor and coaxially to the drive shaft and can be driven by the drive shaft and is therefore rotatable about the axis of rotation relative to the stator, such that the vehicle wheel can be driven by the rotor via the drive shaft. In particular, the vehicle wheel is connected to the drive shaft in a rotationally fixed manner, in particular permanently and / or non-destructively detachable. In particular, the vehicle wheel is formed separately from the drive shaft and is connected to the drive shaft in a rotationally fixed manner, in particular permanently and / or non-destructively detachable. Thus, the vehicle wheel is preferably connected to the drive shaft in a non-destructively detachable manner such that the vehicle wheel is connected to the drive shaft in a rotationally fixed manner. Thus, the vehicle wheel can rotate with the drive shaft about the axis of rotation relative to the stator and also relative to the wheel carrier.With respect to a torque flow along which the respective drive torque for driving the vehicle wheel can be transmitted from the rotor to the vehicle wheel, the rotor, the drive shaft, and the vehicle wheel are arranged in the torque flow such that the drive shaft is arranged downstream of the rotor and upstream of the vehicle wheel, which is arranged downstream of the drive shaft. Thus, the vehicle wheel can be driven by the drive shaft and is thereby rotatable about the axis of rotation relative to the stator and relative to the wheel carrier. It can also be seen that the vehicle wheel can be driven by the rotor via the drive shaft and is thereby rotatable about the axis of rotation relative to the stator and relative to the wheel carrier.

[0013] The vehicle wheel has, for example, a wheel disc and a rim, which is, for example, in particular permanently, non-rotatably connected to the wheel disc. In principle, it would be conceivable for the rim and the wheel disc to be formed separately from one another and, in particular permanently, non-rotatably connected to one another. Furthermore, it would be possible for the wheel disc and the rim to be integral, i.e., formed integrally with one another, so that the wheel disc and the rim are formed from a single piece and are thereby, in particular, permanently non-rotatably connected to one another. In particular, the rim is a radially outer, in particular outermost, part of the vehicle wheel, also simply referred to as the wheel. For example, a tire, in particular of the vehicle wheel, is provided, which is formed in particular from rubber and is formed separately from the rim and the wheel disc, wherein the tire is fastened to the rim, so that the tire is, so to speak, mounted on the rim.In particular, when the vehicle wheel rolls on the aforementioned ground, the tire rolls, in particular directly, on the ground. For example, the vehicle wheel, in particular the wheel disc, has a particularly central fastening area which is connected in a rotationally fixed manner to the drive shaft, so that the vehicle wheel is rotationally fixedly connected to the drive shaft via the wheel disc. Very particularly, the central fastening area and thus the wheel disc and, via the wheel disc, the vehicle wheel are screwed to the drive shaft and are thereby non-destructively detachably fastened to the drive shaft such that the vehicle wheel is rotationally fixedly connected to the drive shaft. The axis of rotation is also referred to as the main axis of rotation of the wheel hub drive, the axial direction of which coincides with the main axis of rotation. The wheel hub drive has a radial direction which runs perpendicular to the axial direction of the wheel hub drive and thus perpendicular to the main axis of rotation.The rotor and preferably also the stator are arranged, in particular at least partially, axially overlapping the rim. For example, the stator is connected, in particular permanently, to the wheel carrier in a rotationally fixed manner.

[0014] Preferably, the electrical machine is designed as a high-voltage component whose electrical voltage, in particular electrical operating or nominal voltage, is preferably greater than 50 volts, in particular greater than 60 volts, and very preferably amounts to several hundred volts.

[0015] In the context of the present disclosure, the feature “radially overlapping” is to be understood as follows: Two elements, in particular those that are at least substantially rotationally symmetrical, are arranged radially, in particular with respect to one another, in particular with respect to a common axis running, for example, in the radial direction of the wheel hub drive and / or in the radial direction of the wheel hub drive, if they are each arranged at least partially in a region of the same radial coordinates, in particular the same angular coordinates. The term “radial” refers to the radial direction of the wheel hub drive. In other words, the term “radial” means the radial direction of the wheel hub drive. When reference is made above and below to the radial direction, this means the radial direction of the wheel hub drive, unless otherwise stated.

[0016] In particular, it is provided that the rotor and preferably also the stator are each arranged at least partially radially overlapping the wheel disc.

[0017] The feature “axially overlapping” is to be understood as follows: Two elements, such as the rotor and the rim, are arranged axially overlapping, in particular with respect to one another, with respect to the common axis, which runs in particular in the axial direction of the wheel hub drive, and / or in the axial direction of the wheel hub drive, if they are each arranged at least partially in a region of the same axial coordinates. In the context of the present disclosure, the term “axial” is to be understood as the axial direction of the wheel hub drive. In other words, the term “axial” means the axial direction of the wheel hub drive. In other words, “axial” refers to the axial direction of the wheel hub drive, and “radial” refers to the radial direction of the wheel hub drive.When reference is made to the axial direction above and below, this refers to the axial direction of the wheel hub drive, unless otherwise stated.

[0018] In particular, it can be provided that the rotor and preferably also the stator is or are arranged radially inside the rim. In the context of the present disclosure, the feature that a first component is arranged radially inside a second component is to be understood that the first component is arranged in a region of smaller radii than the second component, in particular in the radial direction of the wheel hub drive, in particular with respect to the main axis of rotation, so that the aforementioned radii relate to the main axis of rotation or run perpendicular to the main axis of rotation and thus perpendicular to the axial direction of the wheel hub drive. Furthermore, the feature that a first component is arranged axially inside a second component is to be understood that in the installed position of the wheel hub drive,which assumes its installed position in the fully manufactured state of the motor vehicle having the wheel hub drive and, in particular with respect to straight-ahead travel of the motor vehicle, that is to say in particular when a steering system of the motor vehicle is set to cause the motor vehicle to travel straight ahead, the first component, which is arranged axially within the second component, is arranged on one side of the second component towards a centre of the motor vehicle, also referred to as the vehicle centre, thus the first component is arranged on a side of the second component facing the centre of the motor vehicle, so that the first component is arranged further inside, that is to say closer to the centre of the motor vehicle, than the second component, in particular when viewed in the transverse direction of the motor vehicle.

[0019] The wheel hub drive also has a planetary gear, which is also referred to as a planetary set or planetary gear set. Very preferably, the planetary gear is arranged coaxially to the rotor and thus coaxially to the drive shaft. The drive shaft can be driven by the rotor via the planetary gear. The planetary gear has, for example, a sun gear, which is preferably arranged coaxially to the rotor and preferably driven by the rotor and can therefore be rotated about the axis of rotation relative to the stator and relative to the wheel carrier. The sun gear is or can be connected to the rotor in a rotationally fixed manner. Preferably, the sun gear is, in particular permanently, connected to the rotor in a rotationally fixed manner. The planetary gear also has, for example, a ring gear. The planetary gear also has a planet carrier, which can be or can be coupled to the drive shaft in a rotationally fixed manner.In particular, the planet carrier is, for example, permanently coupled to the drive shaft in a rotationally fixed manner. The planet carrier is arranged coaxially to the sun gear and coaxially to the ring gear and is rotatable about the axis of rotation relative to the stator and relative to the gear carrier. Because it is drivable by the rotor, the sun gear is an input of the planetary gear system, via whose input the respective drive torque can be introduced into the planetary gear system. The planet carrier is an output of the planetary gear system, via whose output the respective drive torque or a respective torque resulting from the respective drive torque can be discharged from the planetary gear system. With respect to the aforementioned torque flow, the planetary gear system is arranged in the torque flow such that the planetary gear system is arranged upstream of the drive shaft and downstream of the rotor.With respect to the torque flow, the sun gear and the planet carrier are arranged in the torque flow such that the sun gear is arranged downstream of the rotor and upstream of the planet carrier, which is arranged downstream of the sun gear and upstream of the drive shaft.

[0020] For example, the wheel hub drive comprises a housing, wherein, for example, the stator and / or the rotor and / or the planetary gear and / or the drive shaft can each be arranged at least partially within the housing. Preferably, the ring gear is connected to the housing in a rotationally fixed manner, in particular permanently. Thus, the drive shaft, the planet carrier, the sun gear, and the rotor are rotatable about the rotational axis relative to the housing and relative to the ring gear.

[0021] In the context of the present disclosure, the feature that two components, such as the sun gear and the rotor, are connected to one another in a rotationally fixed manner, is to be understood as meaning that the components connected to one another in a rotationally fixed manner are arranged coaxially to one another and, in particular when the components are driven, rotate together or simultaneously about a component rotation axis common to the components, such as the main rotation axis, at the same angular velocity, in particular relative to a reference element, such as the wheel carrier or the housing. In other words, two elements, in particular rotatably mounted, are connected to one another in a rotationally fixed manner if they are arranged coaxially to one another, in particular with respect to their component rotation axis and / or with respect to a rotational symmetry axis, and if they are connected to one another in such a way that they always rotate with the same angular velocity.An element is connected to the housing in a rotationally fixed manner if it cannot be rotated relative to the housing. Thus, an element is connected to the wheel carrier in a rotationally fixed manner if it cannot be rotated relative to the wheel carrier.

[0022] The feature that two components are connected or coupled to one another in a torque-transmitting manner means that torques can be transmitted between the components. If the components are connected or coupled to one another in a rotationally fixed manner, the components are also connected or coupled to one another in a torque-transmitting manner. Two components connected to one another in a torque-transmitting manner can thus be connected to one another in a torque-transmitting manner. Furthermore, it is conceivable that two components connected to one another in a torque-transmitting manner are connected to one another in a torque-transmitting manner via an intermediate transmission unit, so that torques can be transmitted between the components via the transmission unit while the components are connected to one another in a torque-transmitting manner, although the components can be rotatable relative to one another.

[0023] The feature that two components are permanently connected or coupled to one another in a torque-transmitting manner does not mean that a switching element is provided that can be switched between a coupling state that connects or couples the components to one another in a torque-transmitting manner and a decoupling state in which no torque can be transmitted between the components via the switching element. Rather, the components are always and therefore permanently torque-transmitting, i.e., connected or coupled to one another in such a way that torque can be transmitted between the components. Thus, for example, one of the components can be driven by the other component, or vice versa.The feature that two components are permanently connected or coupled to one another in a rotationally fixed manner means that a switching element is not provided which can be switched between a coupling state that connects or couples the components to one another in a rotationally fixed manner and a decoupling state in which the components are decoupled from one another and rotatable relative to one another, so that no torque can be transmitted between the components via the switching element. Instead, the components are always connected or coupled to one another, thus permanently connected or coupled to one another in a rotationally fixed manner. Furthermore, the feature that two components can be connected or coupled to one another in a rotationally fixed manner means that a switching element, such as a clutch, is assigned to the components, wherein the switching element can be switched between at least one coupling state and at least one decoupling state.In the coupled state, the components are connected or coupled to one another in a rotationally fixed manner by means of the switching element. In the uncoupled state, the components are decoupled from one another, such that in the uncoupled state the components can rotate relative to one another about the component rotation axis and no torque can be transmitted between the components via the switching element. The same applies to the feature that two components can be connected or coupled to one another in a torque-transmitting manner. Thus, for example, the feature that two components can be connected or coupled to one another in a torque-transmitting manner is to be understood as meaning that a switching element is assigned to the components, wherein the switching element can be switched between at least one connected state and at least one released state.In the connected state, the components are coupled or connected to one another by means of the switching element in a torque-transmitting manner, so that torque can be transmitted between the components, particularly via the switching element. In the released state, the components are decoupled from one another, so that in the released state, no torque can be transmitted between the components via the switching element.

[0024] The feature that two elements are formed in one piece, i.e. in one piece with each other, is to be understood that the elements are not formed separately from each other and connected to each other, but the elements are formed from a single piece and thus formed in one piece, i.e. in one piece with each other, so that the elements are formed from a body formed in one piece, thus formed from a single piece and thus manufactured integrally and thus formed as a monoblock.

[0025] The wheel hub drive also has an oil distribution element, which is also referred to as an oil distribution element and is designed as a cup-shaped cover element. The oil distribution element is designed separately from the drive shaft, separately from the rotor, and separately from the planetary gear. In particular, the drive shaft and the rotor, and thus preferably also the sun gear and the planet carrier, are rotatable relative to the oil distribution element, wherein the oil distribution element is preferably connected at least indirectly, in particular directly, in a rotationally fixed manner to the housing and / or the wheel carrier.

[0026] The oil distribution element closes off an oil chamber of the wheel hub drive through which oil can flow and is thus intended to temporarily hold the oil in a direction extending in the axial direction of the rotor and pointing away from the vehicle wheel. For example, the oil distribution element is arranged on a side of the planetary gear set pointing away from the vehicle wheel in the axial direction of the rotor. The axial direction of the rotor corresponds to the axial direction of the wheel hub drive, and vice versa.

[0027] The oil is a liquid lubricant that can be used to lubricate and / or cool at least one area of ​​the wheel hub drive. In particular, the oil is a component of the wheel hub drive. The oil chamber is therefore also referred to as the lubricant chamber. In particular, the oil chamber is at least partially and directly delimited in the aforementioned direction by the oil distribution element and is thus sealed off in this direction.

[0028] The oil distribution element has a supply part protruding from a base region of the oil distribution element, wherein it is conceivable for the base region and the supply part to be formed from a single piece, thus being designed as a single integral part. The supply part has a supply channel through which the oil can flow and which opens into a connection space, wherein the connection space is arranged such that the axis of rotation runs through the connection space, thus intersecting the connection space. The connection space is thus arranged in a region of the axis of rotation. In particular, the connection space is a space of the oil distribution element, wherein, for example, the connection space is delimited, in particular directly, by the oil distribution element, in particular by an inner circumferential surface of the oil distribution element.At least a portion of the oil flowing through the supply channel can be introduced into the connection chamber via the supply channel, which opens at least indirectly into a hollow longitudinal region of the drive shaft, whereby at least a portion of the oil introduced into the connection chamber can be fed to the hollow longitudinal region, and thus at least a portion of the oil introduced into the connection chamber can be introduced into the longitudinal region. The hollow longitudinal region is an inner region of the drive shaft, also referred to simply as the shaft, which is also referred to as the hub inner region or designed as the hub inner region, the hollow longitudinal region of which can be supplied with the oil (lubricant) in a particularly space-saving, effective and efficient manner. The aforementioned region to be lubricated and preferably also cooled by means of the oil is or thus comprises, for example, at least the hollow longitudinal region.Alternatively or additionally, the area of ​​the wheel hub drive to be lubricated and preferably also cooled by the oil can have at least one sub-area of ​​the wheel hub drive provided in addition to the longitudinal area and different from the longitudinal area. It is conceivable that, starting from the hollow longitudinal area, the oil introduced into the hollow longitudinal area can be further conducted, in particular into the aforementioned further sub-area of ​​the wheel hub drive, thereby ensuring a particularly advantageous supply of the area and, for example, the sub-area with oil.

[0029] Preferably, the planetary gear set comprises a plurality of planetary gears, each of which is rotatably mounted on the planetary carrier. The respective planetary gear meshes simultaneously with the sun gear and the ring gear.

[0030] In order to introduce the oil into the hollow longitudinal section in a particularly space-efficient and targeted manner, thus achieving a particularly advantageous supply of oil to at least the wheel hub drive area, one embodiment of the invention provides that the oil distribution element has an oil lance, which is provided in particular in addition to the supply part and protrudes from the base area of ​​the oil distribution element. This oil lance, also simply referred to as a lance, has a supply channel fluidically connected to the connection space and opening into the hollow longitudinal section. In particular, the oil lance protrudes into the hollow longitudinal section, particularly in the axial direction of the wheel hub drive.Preferably, the base region and the supply part are arranged outside the hollow longitudinal region and in particular outside the drive shaft, wherein the oil lance protrudes into the hollow longitudinal region of the drive shaft, in particular in the axial direction of the wheel hub drive, so that the oil lance is arranged at least partially in the hollow longitudinal region of the drive shaft and thus in the drive shaft. In the flow direction of the oil flowing through the feed channel and the supply channel and thereby flowing to and into the hollow longitudinal region, the supply channel is arranged downstream of the connection space and downstream of the feed channel, which is arranged upstream of the connection space and upstream of the supply channel, so that the connection space is arranged downstream of the feed channel and upstream of the supply channel.

[0031] Preferably, the supply part protrudes from the base region in a first direction, and the oil lance protrudes from the base region in a second direction extending obliquely or perpendicularly to the first direction, thereby enabling a particularly space-efficient supply of oil to the hollow longitudinal region. The feature that the first direction and the second direction extend obliquely or perpendicularly to one another is understood to mean that the first direction extends perpendicularly to a first directional plane and the second direction extends perpendicularly to a second directional plane, wherein the directional planes extend obliquely or perpendicularly to one another.

[0032] According to the invention, the oil distribution element has at least one first supply opening branching off, in particular directly, from the supply channel and / or from the connection space, which is also referred to as the first outlet opening. By means of the oil distribution element, the oil flowing through the supply channel, i.e. a total amount of oil flowing through the supply channel, can be divided into at least two partial amounts, namely a first partial amount that can be introduced into the hollow longitudinal region via the supply channel and a second partial amount that can be fed via the first supply opening, bypassing the hollow longitudinal region, i.e. without flowing through the hollow longitudinal region, to a supply region different from the hollow longitudinal region and / or to a component of the wheel hub drive different from the hollow longitudinal region and thus, in particular, completely spaced from the hollow longitudinal region.This allows for a particularly advantageous supply of oil to at least the wheel hub drive area. Using the oil distribution element, the total amount can be distributed into the partial amounts in a space-efficient and demand-based manner, so that the hollow longitudinal area, on the one hand, and the supply area and / or the component, on the other, can be advantageously supplied with oil.

[0033] In a further embodiment of the invention, it is provided that the second partial quantity can be supplied to the supply area and / or the component of the wheel hub drive via the first supply opening, bypassing at least part of the oil lance and the supply channel. Alternatively or additionally, the second partial quantity can be supplied to the supply area and / or the component of the wheel hub drive via the first supply opening, bypassing at least the connection space. This allows the supply area or the component to be advantageously supplied with oil and thus advantageously lubricated and / or cooled by the oil.

[0034] It has proven particularly advantageous if the component is a radial bearing of the wheel hub drive, preferably designed as a rolling bearing. For example, the first supply opening, also referred to as the first outlet opening, is arranged in a first radial region of an inner bearing ring of the radial bearing, so that the radial bearing can be supplied with oil particularly advantageously via the first supply opening. This allows the radial bearing to be advantageously lubricated and / or cooled.

[0035] According to the invention, the supply region comprises planetary gear teeth of the planetary gears of the planetary gear. For example, the first supply opening is arranged in a second radial region, in particular of the planetary gear teeth. In other words, it is conceivable that the first supply opening and the radial bearing, in particular the inner bearing ring of the radial bearing, are arranged so as to at least partially radially overlap one another. Furthermore, it is conceivable that at least one of the planetary gear teeth and the first supply opening are each arranged so as to at least partially radially overlap one another. As a result, the radial bearing or the planetary gear teeth can be supplied with oil in a particularly advantageous manner, so that particularly advantageous lubrication and / or cooling of at least the area of ​​the wheel hub drive can be ensured.

[0036] In order to distribute the oil, in particular the total amount, particularly advantageously, in particular in a particularly space-efficient and demand-based manner, and thus to realize advantageous lubrication and / or cooling of at least the area of ​​the wheel hub drive, a further embodiment of the invention provides that the oil distribution element has at least one second supply opening branching off from the supply channel and / or the connection chamber, which second supply opening is provided in particular in addition to the first supply opening and is spaced apart from the first supply opening. For example, the second supply opening is also referred to as a second outlet opening.By means of the oil distribution element, the oil flowing through the supply channel, i.e., the total amount of oil flowing through the supply channel, can be divided into at least three partial amounts, namely the first partial amount, the second partial amount, which can be supplied via the first supply opening, bypassing the hollow longitudinal region, to the aforementioned radial bearing, which thus constitutes the aforementioned component, and a third partial amount, which can be supplied via the second supply opening, bypassing the hollow longitudinal region, to the planetary gears of the planetary gears. It is preferably provided that the first supply opening is arranged in a first radial region of the radial bearing, in particular the bearing inner ring, so that, for example, the radial bearing, in particular the bearing inner ring of the radial bearing, and the first supply opening are arranged at least partially radially overlapping one another.Furthermore, it is preferably provided that at least one of the planetary gears and the second supply opening are arranged so as to at least partially radially overlap one another. The radial bearing is preferably designed as a rolling bearing.

[0037] In order to realize a particularly compact, i.e. space-efficient design of the wheel hub drive and thus to be able to supply at least the area of ​​the wheel hub drive with oil in a particularly space-efficient manner, a further embodiment of the invention provides that a sensor head, in particular designed separately from the oil distribution element, is attached to the oil distribution element, in particular in such a way that relative movements between the oil distribution element and the sensor head are prevented. The sensor head can be used to detect a rotational speed of the vehicle wheel, which is rotatable about the rotational axis relative to the stator at the rotational speed. The oil distribution element thus has a dual function: Firstly, the oil distribution element is used to distribute the oil as needed and in doing so to introduce it at least into the hollow longitudinal region. Secondly, the oil distribution element is used to hold the sensor head.The sensor head is a sensor element that detects the rotational speed of the vehicle wheel, also known as wheel speed. This dual function of the oil distribution element provides functional integration, as the oil distribution element, designed as a cover, is used both to mount the sensor head and to distribute the oil.

[0038] The background to the invention is in particular that for the oil supply of a drive, lubricant supplies should usually be provided at numerous positions. Typically, a supply common to all lubricant supplies is provided, from which a total lubricant flow is divided into partial flows that flow through the lubricant supplies. This division is carried out volumetrically as required. At the same time, it is usually desirable for sensors to be able to record measured values ​​such as speeds and / or other measured variables. For this purpose, the sensors should be securely attached. Due to limited installation space, this can lead to installation space conflicts between different components. The invention can resolve, avoid, or at least reduce such installation space conflicts. For this purpose, the oil distribution element has the aforementioned dual function.In particular, the oil distribution element can be used, for example, to divide the total quantity, which is, for example, a total volume flow of the oil, into the partial quantities, which are, for example, partial volume flows of the oil. Furthermore, the oil distribution element is preferably used to attach the sensor head to it.

[0039] In order to be able to realize a particularly space-efficient design of the wheel hub drive, a further embodiment of the invention provides for an encoder disk, also referred to as an encoder or coding disk, which is connected at least indirectly and non-rotatably to the drive shaft and thus can rotate with the drive shaft and the vehicle wheel about the axis of rotation relative to the stator. The encoder disk can be used to detect a rotational speed of the drive shaft and thus of the vehicle wheel, wherein the drive shaft and the vehicle wheel can be rotated about the axis of rotation relative to the stator at the speed also referred to as the wheel speed. The encoder disk has a disk region, also referred to as an annular region or designed as an annular region, which extends, for example, in a plane that is perpendicular to the axis of rotation.The disc region at least partially overlaps a rolling bearing of the wheel hub drive in the radial direction of the rolling bearing, the axial direction of which coincides with the axis of rotation and thus corresponds to the axial direction of the wheel hub drive as a whole. For example, the rolling bearing is the aforementioned radial bearing. By means of the rolling bearing, for example, a first part of the wheel hub drive is rotatably mounted on the second part about the axis of rotation relative to a second part of the wheel hub drive. One of the parts, in particular the first part, is or comprises, for example, the planet carrier and / or the drive shaft. The other of the parts, in particular the second part, is or comprises, for example, the housing. The planet carrier is, for example, formed separately from the drive shaft and is connected in a rotationally fixed manner to the drive shaft, for example via a spline.For example, the planetary carrier is rotatably mounted on the housing via the rolling bearing, so that the drive shaft, for example, is rotatably mounted on the housing via the planetary carrier and the rolling bearing. In particular, the rolling bearing is a radial bearing.

[0040] The disk region has a plurality of through-openings, also referred to as through-openings, which are evenly distributed in the circumferential direction of the rolling bearing, which runs around the axial direction of the rolling bearing and thus around the axis of rotation, and which penetrate the disk region in the axial direction of the rolling bearing. On a side of the through-openings facing away from the rolling bearing in the axial direction of the rolling bearing, guide vanes are arranged, each extending in the circumferential direction of the rolling bearing over a respective angular range, also referred to as the radius range, by means of which a fluid can be conveyed through the through-openings and in the direction of the rolling bearing by rotating the encoder disk around the axis of rotation and relative to the stator. The fluid is, for example, a gaseous fluid such as air.Furthermore, the fluid can be a liquid, such as the aforementioned oil. This ensures an advantageous and reliable supply of the fluid to the rolling bearing in a space-efficient manner.

[0041] For example, the sensor head can be used to detect a rotational speed of the sensor disk whose rotational speed corresponds to the rotational speed of the drive shaft of the vehicle wheel, such that the rotational speed of the vehicle wheel can be detected by detecting the rotational speed of the sensor disk. For this purpose, the sensor disk has, for example, a plurality of first magnetic poles and a plurality of second magnetic poles, wherein the first magnetic poles are, for example, magnetic positive poles and the second magnetic poles are, for example, magnetic negative poles. The first magnetic poles and the second magnetic poles are, for example, arranged alternately one after the other in the circumferential direction of the sensor disk running around the axis of rotation, wherein, for example, the sensor head is designed to detect the magnetic poles and thus the rotational speed of the sensor disk and thus of the drive shaft and the vehicle wheel. This enables speed detection with advantageous installation space.

[0042] Further advantages, features, and details of the invention will become apparent from the following description of a preferred embodiment and from the drawings. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respective specified combinations, but also in other combinations or on their own, without departing from the scope of the invention.

[0043] The drawing shows: Fig. 1 shows a partial schematic perspective view of a wheel hub drive for a motor vehicle; Fig. 2 a partial schematic and sectional perspective view of the wheel hub drive; Fig. 3 shows a further schematic and sectioned perspective view of the wheel hub drive; and Fig. 4 shows a partial schematic longitudinal sectional view of the wheel hub drive.

[0044] In the figures, identical or functionally identical elements are provided with the same reference numerals.

[0045] Fig. Figure 1 shows a partial schematic perspective view of a wheel hub drive for a motor vehicle, also referred to simply as a vehicle. The wheel hub drive has an electric machine (not visible in the figures) designed as an axial flux machine, which has a stator and a rotor. The rotor is driven by the stator and is thus rotatable about an axis of rotation relative to the stator. The axis of rotation is also referred to as the main axis of rotation. Via the rotor, the electric machine can provide drive torques for driving a vehicle wheel of the motor vehicle, wherein the wheel hub drive has the vehicle wheel. In other words, the vehicle wheel is a component of the wheel hub drive. Fig. 2 and Fig. 4 it can be seen that the wheel hub drive has a drive shaft 10 arranged coaxially to the rotor and driven by the rotor and thus rotatable about the main axis of rotation relative to the stator. The vehicle wheel is arranged coaxially to the rotor and coaxially to the drive shaft 10 and driven by the drive shaft 10 and thus rotatable about the axis of rotation relative to the stator. In particular, the vehicle wheel is connected, in particular permanently, in a rotationally fixed manner to the drive shaft 10. The wheel hub drive also has a Fig. 3, via which the drive shaft 10 can be driven by the rotor. The planetary gear 12 has a sun gear 14, a planet carrier 16, a ring gear, and planet gears 18, which are rotatably mounted on the planet carrier 16. The respective planet gear 18 is in engagement with the sun gear 14 and the ring gear at the same time. For this purpose, the respective planet gear 18 has a respective planetary toothing, which on the one hand engages with a corresponding sun toothing of the sun gear 14 and on the other hand engages with a corresponding internal toothing of the ring gear. The sun gear 14, the planet carrier 16, the ring gear, the drive shaft 10, and the vehicle wheel are all arranged coaxially with one another. The planet carrier 16 is formed separately from the drive shaft 10 and, in particular, is permanently and non-rotatably connected to the drive shaft 10.The sun gear 14 is, in particular permanently, connected to the rotor in a rotationally fixed manner. Thus, the drive shaft 10, the sun gear 14, the rotor, and the planet carrier 16 are rotatable about the main axis of rotation relative to the stator. The ring gear, on the other hand, is at least indirectly and rotationally fixedly connected to the stator, in particular such that the ring gear is, in particular permanently, connected to a housing in a rotationally fixed manner, while the stator is also, in particular permanently, connected to the housing in a rotationally fixed manner. The drive shaft 10 is driven by the rotor via the planetary gear 12.

[0046] Particularly good looking Fig. 4, it can be seen that the wheel hub drive also has an oil distribution element 20 designed as a pot-shaped cover and also referred to as a cover plate, which is also referred to as an oil distribution element. The oil distribution element 20 closes an oil chamber 22 of the wheel hub drive through which oil can flow in a direction extending in the axial direction of the rotor and the wheel hub drive as a whole and pointing away from the vehicle wheel and in Fig. 4 by an arrow 24. The axial direction of the rotor and the wheel hub drive as a whole coincides with the main axis of rotation, which is Fig. 4 is labeled 26.

[0047] Out of Fig. 1 it can be seen that the oil distribution element 20 has a supply part 30 which protrudes from a base area 28 of the oil distribution element 20 and which has a connection space 32 ( Fig. 2) of the oil distribution element 20. The rotational axis 26 extends through the connection chamber 32 and thus intersects the connection chamber 32. At least a portion of the oil flowing through the supply channel can be introduced into the connection chamber 32 via the supply channel. As will be explained in more detail below, the connection chamber 32 opens at least indirectly into a hollow longitudinal region L of the drive shaft 10, which is designed as a hollow shaft in the present case, whereby at least a portion of the oil introduced into the connection chamber 32 can be fed to the hollow longitudinal region L, thus whereby at least a portion of the oil introduced into the connection chamber 32 can be introduced into the hollow longitudinal region. This is in Fig. 4 by an arrow 34. As in Fig. 4 by a double arrow 36, the oil introduced into the longitudinal region L can, for example, flow through the drive shaft 10 in the radial direction of the drive shaft 10 and thus of the wheel hub drive, in particular through supply channels designed as bores, wherein the oil flowing through the supply channels is guided or supplied to radial bearings 40 of the wheel hub drive designed as rolling bearings by means of the supply channels. By means of the radial bearings 40, for example, the rotor and, via the rotor, the sun gear 14 are rotatably mounted on the drive shaft 10 in the radial direction of the wheel hub drive, or vice versa.

[0048] Out of Fig. 2 and Fig. 4 it is particularly clearly visible that the oil distribution element 20 has an oil lance 42, also simply referred to as a lance, which is provided in particular in addition to the supply part 30 and projects from the base region 28, which has a supply channel fluidically connected to the connection chamber 32 and opening into the hollow longitudinal region L. While the supply part 30 projects from the base region 28 in a first direction, the oil lance 42 projects from the base region 28 in a second direction running obliquely or perpendicular to the first direction, wherein in the present case the second direction coincides with the axial direction and thus with the axis of rotation 26. It can also be seen that the oil lance 42 projects into the hollow longitudinal region L in the second direction.The oil lance 42 has a supply channel 44 fluidically connected to the connection chamber 32 and opening into the hollow longitudinal region L, via which at least the portion of the oil introduced into the connection chamber 32 can be supplied to the longitudinal region L, i.e., can be introduced into the longitudinal region L. This is illustrated by the arrow 34.

[0049] Out of Fig. 4 that the oil distribution element 20 has a first supply opening 46 branching off from the supply channel and / or the connection chamber 32, which is also referred to as the first outlet opening. Furthermore, the oil distribution element 20 has a Fig. 3, which is provided in addition to the first supply opening 46 and spaced from the supply opening 46, and which is also referred to as the second outlet opening.By means of the oil distribution element 20, the oil flowing through the supply channel, that is to say a total quantity of oil flowing through the supply channel, can be divided into at least or exactly three partial quantities, namely a first partial quantity that can be introduced into the hollow longitudinal region L via the supply channel and the oil lance 42, a second partial quantity, illustrated by arrows 48, which can be fed via the first supply opening 46, bypassing the hollow longitudinal region L and bypassing the supply opening 49, to at least one further radial bearing 50 of the wheel hub drive, designed as a rolling bearing, and a third partial quantity, which can be fed to the planetary gears of the planet gears 18 via the second supply opening 49, bypassing the hollow longitudinal region L and bypassing the supply opening 46.As a result, both the planetary gears and the radial bearing 50 can be supplied with the oil and thus lubricated and / or cooled by means of the oil acting as a lubricant, and the radial bearings 40 can also be supplied with the first partial quantity and thus with the oil and thus cooled and / or lubricated by means of the oil.

[0050] The wheel hub drive also has an encoder disk 52, also referred to as an encoder disk, which is formed separately from the planetary gear 12, separately from the drive shaft 10, and separately from the rotor. This encoder disk is non-rotatably connected to the planet carrier 16 and thus to the drive shaft 10 and the rotor, and thus can rotate with the planet carrier 16, the drive shaft 10, the rotor, and also the vehicle wheel about the rotational axis 26 relative to the stator. Thus, the drive shaft 10, the vehicle wheel, the planet carrier 16, and the encoder disk 52 can rotate simultaneously and at the same speed about the rotational axis 26 relative to the stator. Since the speed is a speed of the vehicle wheel, it is also referred to as the wheel speed.

[0051] The wheel hub drive also has a sensor head 54 ( Fig.1), wherein the sensor disk 52 is rotatable about the rotational axis 26 relative to the sensor head 54. By means of the sensor head 54, the sensor disk 52 and thus the rotational speed, and thus the wheel speed, can be detected, i.e., measured. The sensor head 54 is attached, in particular directly, to the oil distribution element 20. The oil distribution element 20 thus has a dual function, since the oil distribution element 20 is used, on the one hand, to divide the total quantity into the partial quantities. On the other hand, the oil distribution element 20 is used to attach the sensor head 54. List of reference symbols 10 Drive shaft 12 planetary gears 14 Sun gear 16 planet carriers 18 Planetary gear 20 Oil distribution element 22 Oil room 24 Arrow 26 axis of rotation 28 Basic area 30 Feeding section 32 Connection compartment 34 Arrow 36 Double arrow 40 radial bearings 42 Oil lance 44 supply channel 46 first supply opening 48 Arrow 49 second supply opening 50 radial bearings 52 encoder disc 54 Sensor head L hollow length range

Claims

[1] Wheel hub drive for a motor vehicle with an electric machine having a stator and a rotor, with a drive shaft (10) arranged coaxially to the rotor, drivable by the rotor, and thereby rotatable about a rotational axis (26) relative to the stator, with a vehicle wheel arranged coaxially to the rotor and coaxially to the drive shaft (10), drivable by the drive shaft (10) and thereby rotatable about the rotational axis (26) relative to the stator, with a planetary gear (12) via which the drive shaft (10) can be driven by the rotor, and with an oil distribution element (20) designed as a pot-shaped cover element, which closes off an oil chamber (22) of the wheel hub drive through which oil can flow in a direction extending in the axial direction of the rotor and pointing away from the vehicle wheel, and has a feed part (30) protruding from a base region (28) of the oil distribution element (20),which has a supply channel through which the oil can flow and which opens into a connection space (32) through which the rotational axis (26) runs, via which at least a portion of the oil flowing through the supply channel can be introduced into the connection space (32), which opens into a hollow longitudinal region (L) of the drive shaft (10), whereby at least a portion of the oil introduced into the connection space (32) can be supplied to the hollow longitudinal region (L), wherein the oil distribution element (20) has at least one first supply opening (46) branching off from the supply channel and / or the connection space (32), wherein by means of the oil distribution element (20), the oil flowing through the supply channel can be divided into at least two partial quantities, namely a first partial quantity which can be introduced into the hollow longitudinal region (L) via the supply channel and a second partial quantity,which can be fed via the first supply opening (46) bypassing the hollow length region (L) to a supply region different from the hollow length region (L) and / or to a component of the wheel hub drive different from the hollow length region (L), and wherein the supply region comprises planetary gears of planetary gears (18) of the planetary gear (12). [2] Wheel hub drive according to claim 1, characterized by in that the oil distribution element (20) has an oil lance (42) projecting from the base region (28) of the oil distribution element (20), which oil lance has a supply channel (44) fluidically connected to the connection space (32) and opening into the hollow longitudinal region (L), via which at least part of the oil introduced into the connection space (32) can be supplied to the longitudinal region (L). [3] Wheel hub drive according to one of the preceding claims, characterized by , that - the second partial quantity can be supplied to the supply area and / or the component of the wheel hub drive via the first supply opening (46), also bypassing at least part of the oil lance (42) and the supply channel (44); and / or - the second partial quantity can be supplied to the supply area and / or the component of the wheel hub drive via the first supply opening (46) even bypassing at least the connection space (32). [4] Wheel hub drive according to one of the preceding claims, characterized by that the component is a radial bearing (50) of the wheel hub drive. [5] Wheel hub drive according to one of the preceding claims, characterized byin that the oil distribution element (20) has at least one second supply opening (49) branching off from the supply channel and / or the connection space (32), wherein by means of the oil distribution element the oil flowing through the supply channel can be divided into at least three partial quantities, namely the first partial quantity, the second partial quantity which can be fed to a radial bearing (50) as the component of the wheel hub drive via the first supply opening (46) bypassing the hollow longitudinal region (L), and a third partial quantity which can be fed to planetary gearings of planet wheels (18) of the planetary gear (12) via the second supply opening (49) bypassing the hollow longitudinal region (L). [6] Wheel hub drive according to claim 5, characterized by , that: - the third partial quantity can be supplied to the planetary gears via the second supply opening (49) bypassing at least part of the oil lance (42) and the supply channel (44); and / or - the third partial quantity can be fed to the planetary gears via the second supply opening (49) also bypassing at least the connection space (32). [7] Wheel hub drive according to one of the preceding claims, characterized by that a sensor head (54) is attached to the oil distribution element (20), by means of which a rotational speed of the vehicle wheel can be detected. [8] Wheel hub drive according to one of the preceding claims, characterized bya sensor disc (52) which is connected at least indirectly and in a rotationally fixed manner to the drive shaft (10), by means of which a rotational speed of the drive shaft (10) and thus of the vehicle wheel can be detected, wherein the sensor disc (52) has a disc region by which a rolling bearing of the wheel hub drive is at least partially overlapped in the radial direction of the rolling bearing, wherein the disc region has a plurality of through-openings arranged uniformly distributed in the circumferential direction of the rolling bearing and penetrating the disc region in the axial direction of the rolling bearing, and wherein on a side of the through-openings facing away from the rolling bearing in the axial direction of the rolling bearing, guide vanes are arranged which each extend in the circumferential direction of the rolling bearing over a respective angular range,by means of which a fluid can be conveyed through the passage openings and in the direction of the rolling bearing by rotating the encoder disc (52) around the axis of rotation.,

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