Drive device for a motor vehicle and motor vehicle

Abstract

The invention relates to a drive device (1) for a motor vehicle, comprising at least one vehicle axle (2) having two vehicle wheels (3, 4), at least one drive motor (6), a transmission path (11) via which the vehicle wheels (3, 4) can be driven by the drive motor (6), and a freewheel (18) arranged in the transmission path (11) between two elements (12, 13) of the transmission path (11) that can be driven by the drive motor (6) and are thus rotatable. A coupling device (21) is provided in addition to the freewheel (18), which coupling device can be switched between an open state and a closed state.

Description

[0001] The invention relates to a drive device for a motor vehicle, in particular for a motor vehicle, according to the preamble of patent claim 1. Furthermore, the invention relates to a motor vehicle, in particular a motor vehicle, with such a drive device.

[0002] DE 10 2008 015 225 A1 discloses a drive module for a motor vehicle, comprising a hybrid drive module and a converter unit. US 10 233 977 B2 discloses a clutch assembly for a drive train of a motor vehicle. DE 10 2019 214 131 A1 discloses a transmission device for a motor vehicle. Furthermore, CN 107914562 B discloses a power transmission device for a motor vehicle.

[0003] The object of the present invention is to provide a drive device for a motor vehicle and a motor vehicle with such a drive device, so that a particularly efficient operation of the motor vehicle can be realized.

[0004] This object is achieved according to the invention by a drive device having the features of patent claim 1 and by a motor vehicle having the features of patent claim 7. Advantageous embodiments of the invention are the subject of the dependent claims.

[0005] A first aspect of the invention relates to a drive device for a motor vehicle, also simply referred to as a vehicle, whose interior, also referred to as the passenger compartment or passenger cell, is formed, i.e. delimited, for example, by a structure designed, for example, as a self-supporting body. Thus, for example, while the motor vehicle is traveling, people such as the driver of the motor vehicle can be present in the interior. Very preferably, the motor vehicle is a motor vehicle, in particular a passenger car. In its fully manufactured state, the motor vehicle has the drive device and can thus be driven by means of the drive device. The drive device has at least one vehicle axle, also simply referred to as an axle, which has, in particular at least or exactly two vehicle wheels, also simply referred to as wheels.The vehicle axle is also referred to as the first vehicle axle. When reference is made above and below to the vehicle axle, this refers to the first vehicle axle unless otherwise stated. The vehicle wheels of the vehicle axle are also referred to as the first vehicle wheels. When reference is made above and below to the vehicle wheels, this refers to the first vehicle wheels unless otherwise stated. For example, in its fully manufactured state, the motor vehicle has at least or exactly two vehicle axles arranged consecutively and thus one behind the other in the longitudinal direction of the motor vehicle, namely the aforementioned first vehicle axle and a second vehicle axle. The previous and following statements regarding the first vehicle axle can easily be applied to the second vehicle axle and vice versa.For example, in the fully manufactured state of the motor vehicle, the vehicle wheels are arranged on opposite sides of the motor vehicle and thus of the body in the transverse direction of the motor vehicle. The vehicle wheels 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 is driven along the ground while being supported downwards on the ground in the vertical direction of the motor vehicle via the ground contact elements, the vehicle wheels (ground contact elements) roll, in particular directly, on the ground.

[0006] The drive device also has at least one drive motor. Furthermore, the drive device has a transmission path, in particular a mechanical one, which is also referred to as a transmission mechanism, in particular a mechanical one, or is designed as a transmission mechanism, in particular a mechanical one. The vehicle wheels and thus the motor vehicle can be driven via the transmission path by means of the drive motor. This means in particular the following: The respective vehicle wheel can be rotated, for example, about a respective wheel rotation axis relative to the body. The respective vehicle wheel can be driven by the drive motor via the transmission path and can thus be rotated about the respective wheel rotation axis of the respective vehicle wheel relative to the body.In particular, it is provided that the vehicle wheels are arranged at the same height when viewed in the longitudinal direction of the motor vehicle, so that it is preferably provided that the vehicle wheels of the vehicle axle are not offset from one another when viewed in the longitudinal direction of the motor vehicle. For example, the drive motor can provide output torques, also simply referred to as torques, in particular via an output shaft of the drive motor, by means of which output torques the vehicle wheels can be driven via the transmission path. The respective drive torque can be transmitted via the respective transmission path from the drive motor, in particular from the output shaft, to the respective vehicle wheel, whereby the respective vehicle wheel can be driven and thus can be rotated in particular about the respective wheel rotation axis of the respective vehicle wheel relative to the body.The transmission path has at least two elements, namely a first element and a second element. Each element is preferably designed as a solid body. For example, each element is a shaft or shaft element. The drive torque can thus be transmitted from the drive motor to the vehicle wheels via the elements. The elements can be driven by the drive motor and are therefore rotatable, in particular relative to a housing of the drive device. For example, at least one of the elements is at least partially arranged in the housing. In particular, it is conceivable that both elements are each at least partially arranged in the housing.

[0007] The drive device also has a freewheel, which is provided in particular in addition to the elements and is arranged in the transmission path and between the elements. This means, for example, that with respect to a flow direction in which the respective drive torque can be or is transmitted via the transmission path from the electric machine to the respective vehicle wheel, in particular in order to thereby cause the motor vehicle to travel forward, the freewheel is arranged downstream of one of the elements and upstream of the other element, in particular downstream of the first element and upstream of the second element. The forward travel of the motor vehicle is to be understood as travel of the motor vehicle forward in the longitudinal direction of the motor vehicle. The drive motor can also be used to drive the motor vehicle backward, the reversing of which is explained in more detail below.The term “reverse travel” means the travel of the motor vehicle backwards in the longitudinal direction of the vehicle.

[0008] In order to achieve particularly efficient and thus low-energy operation of the motor vehicle, the invention provides that the drive device has a coupling device provided in addition to the freewheel, which coupling device can be switched between an open state and a closed state. For example, the coupling device can be controlled, in particular mechanically and / or electrically and / or pneumatically and / or hydraulically, and can thereby be switched between the closed state and the open state. This control of the coupling device can be effected or carried out, for example, by means of an electronic computing device of the drive device.

[0009] The first element is rotatable about an element rotation axis, also simply referred to as the axis of rotation, in particular relative to the housing. When reference is made below to the axis of rotation, this means the element rotation axis, unless otherwise stated. Very preferably, the elements are arranged coaxially to one another, so that, in particular, the second element is also rotatable about the axis of rotation, in particular relative to the housing. In particular, the first element can be rotated optionally in a first direction of rotation running around the axis of rotation or in a second direction of rotation running around the axis of rotation and opposite the first direction of rotation, in particular relative to the housing.

[0010] The freewheel itself, that is to say, for example, considered on its own, is designed in such a way that the first element is connected to the second element in a rotationally fixed manner in the first direction of rotation by means of the freewheel, so that then and in particular whenever the first element is driven, in particular by means of the drive motor, and is thereby rotated about the axis of rotation in the first direction of rotation, in particular relative to the housing, the first element takes the second element along via the freewheel, and thus the second element is driven by the first element via the freewheel and is thereby rotated, in particular about the axis of rotation in the first direction of rotation, preferably relative to the housing.In addition, the freewheel itself, that is to say considered on its own, is designed such that the freewheel permits a rotation in the second direction of rotation relative to the second element, in particular complete and most particularly unlimited rotation, so that a transmission of torques about the axis of rotation and in the second direction of rotation from the first element to the second element via the freewheel is prevented. In other words, if, for example, the first element is rotated about the axis of rotation in the second direction of rotation, in particular relative to the housing, the second element is not driven by the first element via the freewheel and thus is not rotated by the first element via the freewheel in the second direction of rotation, in particular about the axis of rotation and preferably relative to the housing.Thus, for example, when considering the freewheel alone, it is possible that if the second element rotates faster around the axis of rotation in the first direction of rotation, i.e. at a higher speed than the first element, the second element does not drive the first element via the freewheel, and therefore the first element is not driven by the second element via the freewheel and is therefore not rotated by the second element in the first direction of rotation via the freewheel.

[0011] In the open state of the coupling device, the first element is connected to the second element in a rotationally fixed manner with respect to the freewheel and the coupling device exclusively by means of the freewheel in the first direction of rotation running around the axis of rotation, so that in order to effect the forward travel of the motor vehicle by means of the drive engine, in particular by means of the output shaft, the first element can be driven and is thereby rotatable in particular relative to the housing about the axis of rotation in the first direction of rotation, whereby in order to effect the forward travel the second element can be driven by the first element via the freewheel and is thereby rotatable in particular about the axis of rotation and in the first direction of rotation and in particular relative to the housing.This means that when the first element is rotated, for example by means of the drive motor, in the first direction of rotation about the axis of rotation, in particular relative to the housing, the first element takes the second element along via the freewheel, whereby the second element is driven by the first element via the freewheel in such a way that the second element is rotated, in particular about the axis of rotation and in the first direction of rotation, very preferably relative to the housing, although the coupling device is in the open state.

[0012] In the open state of the coupling device, the freewheel and the coupling device allow a second direction of rotation opposite to the first direction of rotation, running around the direction of rotation and relative to the second element, in particular a complete and very particularly free, i.e. unlimited rotation of the first element, so that in a pushing operation of the drive device or of the motor vehicle, also referred to as first overrun operation, the second element, which is driven in the overrun operation by means of the vehicle wheels and thereby rotates, in particular around the axis of rotation in the first direction of rotation, very particularly relative to the housing, does not drive the first element via the freewheel and rotates it in the first direction of rotation.In other words, if the coupling device is in the open state and the vehicle wheels are not driven via the transmission path by means of the drive engine, the motor vehicle rolling, in particular forwards, and the vehicle wheels are consequently rotating, so that the motor vehicle or the drive device is in the first overrun mode, the vehicle wheels drive the second element, whereby the second element is rotated in particular about the axis of rotation in the first direction of rotation and very preferably relative to the housing, while, however, the first element is not driven by the second element via the freewheel in such a way that the first element is rotated about the axis of rotation in the first direction of rotation, in particular relative to the housing.In other words, the second element does not carry the first element via the freewheel, but the first element is not driven by the second element via the freewheel, so that the vehicle wheels do not carry the first element and consequently the drive engine.

[0013] In the closed state of the coupling device, the first element is connected to the second element in a rotationally fixed manner in the second direction of rotation by means of the coupling device, in particular with regard to the freewheel and the coupling device exclusively by means of the coupling device, so that in order to effect reverse travel of the motor vehicle by means of the drive engine the first element can be driven and is thereby rotatable about the axis of rotation in the second direction of rotation, in particular relative to the housing, whereby in order to effect reverse travel the second element can be driven by the first element via the coupling device and is thereby rotatable in particular about the axis of rotation in the second direction of rotation and very particularly relative to the housing.In other words, if the coupling device is in its closed state while the first element is driven by the drive motor such that the first element is rotated about the axis of rotation in the second direction of rotation and preferably relative to the housing, the second element is driven by the first element via the freewheel and is thereby rotated, in particular, about the axis of rotation in the second direction of rotation and in particular relative to the housing, whereby the motor vehicle is driven backwards or can be driven backwards. The invention thus enables the realization of a needs-based and particularly efficient operation of the drive device and, consequently, of the motor vehicle.

[0014] The freewheel and the coupling device enable a simple, efficient and needs-based decoupling of rotating elements such as the first element and the drive motor or the output shaft, particularly in situations where the full torque is not required, one of which is, for example, the aforementioned overrun mode. In order to decouple the first element and thus the drive motor in overrun mode, the coupling device is set to the open state, i.e. activated, whereby the vehicle wheels and the second element do not drag the first element and the drive motor along in overrun mode. This enables particularly efficient operation of the drive device. When overrun mode is mentioned above and below, this means that, unless otherwise stated, this means the first overrun mode.At the same time, the invention enables the motor vehicle to reverse in a simple and efficient manner. For this purpose, the locking state of the coupling device is or will be set, i.e., activated.

[0015] In addition, the invention enables a particularly advantageous implementation of all-wheel or four-wheel functionality, both when driving forward and when driving backward. The vehicle wheels of the first vehicle axle are also referred to as first vehicle wheels. When reference is made above and below to the vehicle wheels, this refers to the first vehicle wheels unless otherwise stated. The second vehicle axle has, for example, at least or exactly two second vehicle wheels, which are arranged, for example, on the sides opposite one another in the transverse direction of the vehicle. The previous and following statements regarding the first vehicle axle and the first vehicle wheels can easily be applied to the second vehicle axle and the second vehicle wheels. The drive motor is also referred to as the first drive motor.When reference is made above and below to the drive motor, this means the first drive motor unless otherwise stated. The second vehicle axle has, for example, at least one or exactly one second drive motor, by means of which, for example, the second vehicle wheels can be driven. The invention makes it possible to drive the first vehicle wheels and the second vehicle wheels, in particular simultaneously, both during forward travel and during reverse travel, in such a way that, for example, during forward travel the first vehicle wheels are driven by the first drive motor and, in particular simultaneously, the second vehicle wheels are driven by the second drive motor, for example in such a way that during reverse travel the first vehicle wheels are driven by the first drive motor and, in particular simultaneously, the second vehicle wheels are driven by the second drive motor.For this purpose, the coupling device is a switchable coupling device, i.e. a switchable coupling element which can be switched selectively into the closed state and the open state. In the closed state, the freewheel for reversing is bridged, so that an all-wheel or four-wheel function of the motor vehicle can be realized for reversing and thus, for example, in a reverse gear which is engaged to effect reversing. The all-wheel or four-wheel function is to be understood in particular that both the first vehicle wheels and the second vehicle wheels are driven, in particular simultaneously, in particular such that the first vehicle wheels are driven by means of the first drive motor and, in particular simultaneously, the second vehicle wheels are driven by means of the second drive motor.

[0016] Since in or through the open state of the coupling device the first element and thus the drive motor is or can be decoupled from the second element and the vehicle wheels, excessive losses of the drive device can be avoided, particularly in overrun mode, so that particularly efficient operation can be achieved. In particular, the coupling device enables a, particularly purely mechanical, decoupling of the second element and thus the drive motor, particularly through or in the open state of the coupling device. By decoupling the first element and the drive motor, they are shut down and therefore no longer cause any losses, so that particularly efficient operation of the drive device can be achieved.In the closed state, the coupling device enables torques acting around the axis of rotation and in the second direction of rotation to be transmitted from the first element via the freewheel to the second element, so that the second element can also be driven by the first element via the freewheel when reversing.

[0017] In order to be able to realize particularly efficient operation of the drive train, it is provided in one embodiment of the invention that in the closed state the first element is connected to the second element in a rotationally fixed manner in the first direction of rotation by means of the coupling device, in particular with regard to the freewheel and the coupling device exclusively by means of the coupling device, so that in a further overrun operation of the motor vehicle, also referred to as second overrun operation, the second element can be driven by the vehicle wheels and can therefore be rotated, in particular about the axis of rotation in the second direction of rotation, very particularly relative to the housing, whereby in the further overrun operation the first element can be driven by the second element via the coupling device and can therefore be rotated about the axis of rotation in the first direction of rotation, in particular relative to the housing.As a result, for example, recuperation operation of the drive motor, which is designed as an electric machine, for example, can be implemented in the further overrun mode. If, for example, the motor vehicle rolls forward while the coupling device is in the closed state, the second element is driven and rotated by means of the vehicle wheels in such a way that the first element is driven and rotated via the freewheel by means of the second element in such a way that the first element is rotated about the axis of rotation in the first direction of rotation, in particular relative to the housing. This means that the vehicle wheels and the second element drag the first element and, via this, the drive motor, for example, so that the drive motor, for example, can be operated in generator mode and thus as a generator, in particular if it is designed as an electric machine.By means of the generator, kinetic energy of the motor vehicle, in particular a vehicle rolling forward, can be converted into electrical energy, which is or can be provided by the generator. For example, to drive the motor vehicle using the electric machine and thereby effect forward or reverse travel, the electric machine is operated in motor mode and thus as an electric motor, by means of which the vehicle wheels can be or are driven via the transmission path to effect forward or reverse travel.

[0018] A further embodiment is characterized in that the coupling device is arranged outside the freewheel, which is arranged outside the coupling device. This allows for a particularly simple and efficient design of the drive device.

[0019] It has proven particularly advantageous if the coupling device and the freewheel are viewed along the rotational axis and thus follow one another in the axial direction of the drive device. This ensures a particularly simple and efficient design of the drive device as well as particularly efficient operation of the drive device.

[0020] In order to be able to realize a particularly efficient operation of the drive device, it is provided in a further embodiment of the invention that the coupling device is designed as a positive coupling device, in particular as a claw coupling, wherein by means of the positive coupling device in the closed state the first element is connected in a form-fitting, rotationally fixed manner to the second element in the second direction of rotation.

[0021] Finally, it has proven particularly advantageous for achieving particularly efficient operation if the drive machine is designed as the aforementioned electric machine. The drive machine has a stator and a rotor which can be driven by means of the stator and is therefore rotatable about a machine axis of rotation relative to the stator. It is conceivable that the rotor and the first element are arranged coaxially to one another, so that, for example, the machine axis of rotation coincides with the axis of rotation. Furthermore, it is conceivable that the rotor is arranged off-axis to the first element, so that, for example, the machine axis of rotation and the axis of rotation are spaced apart from one another. It is conceivable that the machine axis of rotation and the axis of rotation run parallel to one another.

[0022] To effect forward travel, the first element can be driven by means of the rotor and can therefore rotate about the axis of rotation in the first direction of rotation, in particular relative to the housing. To effect reverse travel, the first element can be driven by means of the rotor and can therefore rotate about the axis of rotation in the second direction of rotation, in particular relative to the housing. For example, to effect forward travel, the rotor is driven by means of the stator and can therefore rotate in a first direction of rotor rotation relative to the stator about the machine axis of rotation. To effect reverse travel, for example, the rotor is driven by means of the stator and can therefore rotate in a second direction of rotor rotation about the machine axis of rotation relative to the stator. The first direction of rotor rotation and the second direction of rotor rotation run around the machine axis of rotation, the first direction of rotor rotation being opposite to the second direction of rotor rotation or vice versa.This allows a particularly efficient design to be realized, which enables particularly efficient operation of the drive device.

[0023] A second aspect of the invention relates to a motor vehicle, also simply referred to as a vehicle, preferably designed as a motor vehicle, in particular as a passenger car, which has a drive device according to the first aspect of the invention and can be driven by the drive device. Advantages and advantageous embodiments of the first aspect of the invention are to be regarded as advantages and advantageous embodiments of the second aspect of the invention, and vice versa.

[0024] Further details of the invention will become apparent from the following description of a preferred embodiment with the accompanying drawings. Fig. 1 a schematic and partially sectioned view of a drive device for a motor vehicle.

[0025] The only Fig. Figure 1 shows a schematic and partially sectioned view of a drive device 1 for a motor vehicle, also referred to simply as a vehicle. In its fully manufactured state, the motor vehicle has the drive device 1 and can be driven by the drive device 1.

[0026] In its fully manufactured state, the motor vehicle has at least or exactly two vehicle axles arranged consecutively in the longitudinal direction of the motor vehicle and thus one behind the other, namely a first vehicle axle and a second vehicle axle. At least the first vehicle axle and, for example, also the second vehicle axle are components of the drive device 1. The first vehicle axle is in Fig. 1 is shown particularly schematically and designated 2. The vehicle axle 2 of the drive device 1 has at least or exactly two Fig. 1 particularly schematically illustrated vehicle wheels, namely a first vehicle wheel 3 and a second vehicle wheel 4. The vehicle wheels 3 and 4 are arranged on opposite sides S1 and S2 of the motor vehicle in the vehicle transverse direction of the motor vehicle. The vehicle transverse direction is in Fig. 1 by a double arrow 5. The vehicle wheels 3 and 4 are ground contact elements of the motor vehicle and thus of the drive device 1. The vehicle wheels 3 and 4 are assigned, in particular precisely, a drive motor 6 which is common to the vehicle wheels 3 and 4 and by means of which the vehicle wheels 3 and 4 can be driven. Therefore, the drive device 1 comprises the drive motor 6. This means that the drive motor 6 is a component of the drive device 1. In the Fig. In the embodiment shown in Figure 1, the motor vehicle is an electric vehicle, in particular a battery-electric vehicle. The drive motor 6 is designed as an electric machine having a stator 7 and a rotor 8. The rotor 8 is driven by the stator 7 and is thereby rotatable about a machine rotation axis 9 relative to a Fig. 1 particularly schematically illustrated housing 10 of the drive device 1 and rotatable relative to the rotor 8. The machine rotation axis 9 is also referred to as the first rotation axis.

[0027] The drive device 1 has a, in particular mechanical, transmission path 11, via which the vehicle wheels 3 and 4 can be driven by means of the rotor 8 and thus by means of the electric machine (drive machine 6). The transmission path 11 has at least or exactly two elements, which in this case are mechanical elements and thus designed as solid bodies. A first of the elements is designated 12, and a second of the elements is designated 13. In the Fig. 1, the first element 12 is a gearwheel having a toothing 14, for example, formed as a helical toothing. The elements 12 and 13 are driven, in particular, by the drive device 1 to cause the motor vehicle to travel forward and are thereby rotatable relative to the housing 10. The first element 12 is rotatable about a second axis of rotation 15 relative to the housing 10. The elements 12 and 13 are in the embodiment shown in Fig. 1, the elements 13 are arranged coaxially to one another, so that the element 13 can also be rotated about the axis of rotation 15 relative to the housing 10. For example, the drive motor 6, in particular the rotor 8, is coupled to the element 12, in particular permanently, in a torque-transmitting, in particular rotationally fixed manner, so that by driving the rotor 8 by means of the stator 7, the element 12 can be driven by the rotor 8 and thus by means of the drive motor 6, which is designed here as an electric machine, and can thereby be rotated about the axis of rotation 15 relative to the housing. A first direction of rotation running about the axis of rotation 15 is illustrated by an arrow 16, and a second direction of rotation running about the axis of rotation 15, which is opposite to the first direction of rotation, is illustrated by an arrow 17.The element 12 can be driven by the drive motor 6, in particular by the rotor 8, such that the element 12 can be rotated selectively in the first direction of rotation or in the second direction of rotation about the axis of rotation 15 relative to the housing 10. For example, to effect the aforementioned forward travel of the motor vehicle, the element 12 is driven by the drive motor 6 such that the element 12 is rotated about the axis of rotation 15 relative to the housing 10 in the first direction of rotation. As a result, for example, the respective vehicle wheel 3, 4 is rotated about a respective wheel axis of rotation in a respective first wheel direction of rotation, which runs about the respective wheel axis of rotation, relative to the housing 10.To cause the motor vehicle to travel backward, for example, the element 12 is driven by the drive motor 6, in particular by the rotor 8, such that the element 12 is rotated about the axis of rotation 15 relative to the housing 10 in the second direction of rotation opposite to the first direction of rotation. As a result, for example, the respective vehicle wheel 3, 4 is rotated about the respective wheel axis of rotation of the respective vehicle wheel 3, 4 in a respective second wheel direction of rotation. The respective wheel direction of rotation runs about the respective wheel axis of rotation of the respective vehicle wheel 3, 4, wherein the respective first wheel direction of rotation is opposite to the respective second wheel direction of rotation and vice versa. The respective elements 12 and 13 are designed as solid bodies.

[0028] The drive device 1 also has a freewheel 18, which is provided in particular in addition to the elements and is designed, for example, separately from the elements 12 and 13. The freewheel 18 has, for example, two freewheel elements, namely a first freewheel element 19 and a second freewheel element 20. For example, the second freewheel element 20 is, in particular permanently, connected in a rotationally fixed manner to the second element 13. For example, the freewheel element 19 is, in particular permanently, connected in a rotationally fixed manner to the first element 12. The freewheel elements 19 and 20 are arranged coaxially to one another. It is clearly visible that in the Fig. 1, the element 12 is arranged on the element 13. The freewheel 18 is arranged coaxially to the elements 12 and 13. The freewheel 18 is arranged in the transmission path 11 and between the elements 12 and 13, which can be driven by the drive machine 6 and are therefore rotatable in particular relative to the housing 10. The arrangement of the freewheel 18 in the transmission path 11 between the elements 12 and 13 is to be understood in particular in functional terms. This means in particular the following: The rotor 8 is or comprises an output shaft, via which the drive machine 6 can provide drive torques running around the machine axis of rotation 9 for driving the motor vehicle.To effect forward travel, for example, the respective drive torque is transmitted via the transmission path 11 in such a way that the respective drive torque flows or flows in a flow direction via the transmission path 11 from the output shaft to the respective vehicle wheel 3, 4, wherein, with respect to this flow direction, the freewheel 18 is arranged downstream of the element 12 and upstream of the element 13, in particular in that or because, with respect to the said flow direction, the element 12 is arranged upstream of the element 13, and thus the element 13 is arranged downstream of the element 12.

[0029] In order to be able to realize a particularly efficient operation of the drive device 1 and thus of the motor vehicle, the drive device 1 has a coupling device 21 provided in addition to the freewheel 18. The coupling device 21 can be switched between an open state and a closed state, wherein Fig. 1, for example, the open state is shown. In the open state of the coupling device 21, the first element 12 is connected to the second element 13 in a rotationally fixed manner with respect to the freewheel 18 and the coupling device 21 exclusively by means of the freewheel 18 in the first direction of rotation about the axis of rotation 15, so that in order to effect forward travel of the motor vehicle by means of the drive engine 6, the first element 12 can be driven and is thereby rotatable about the axis of rotation 15 in the first direction of rotation relative to the housing 10, whereby in order to effect forward travel, the second element 13 can be driven by the first element 12 via the freewheel 18 and is thereby rotatable about the axis of rotation 15 in the first direction of rotation relative to the housing 10.In the open state of the coupling device 21, the freewheel 18 and the coupling device 21 allow a free, i.e. unlimited, rotation of the first element 12 in the second direction of rotation and relative to the second element 13, so that the first element 12 can be rotated unlimitedly, i.e. freely, about the axis of rotation 15 in the second direction of rotation relative to the element 13 and relative to the housing 10, and so that in a first overrun mode of the motor vehicle, the second element 13, which is driven by the vehicle wheels 3 and 4 in the first overrun mode and thereby rotates about the axis of rotation 15 in the first direction of rotation and relative to the housing 10, does not drive the first element 12 via the freewheel 18 and rotates the axis of rotation 15 relative to the housing 10 in the first direction of rotation.In the first overrun mode, the motor vehicle rolls forward in the vehicle longitudinal direction of the vehicle, so that the respective vehicle wheel 3, 4 rotates about the respective wheel rotation axis of the respective vehicle wheel 3, 4 in the respective first wheel rotation direction, in particular relative to the housing 10.

[0030] In the closed state of the coupling device 21, the first element 12 is connected to the second element 13 in a rotationally fixed manner by means of the coupling device 21 in the second direction of rotation, so that in order to effect reverse travel of the motor vehicle by means of the drive engine 6, the first element 12 can be driven and is thereby rotatable about the axis of rotation 15 in the second direction of rotation relative to the housing 10, whereby in order to effect reverse travel, the second element 13 can be driven by the first element 12 via the coupling device 21 and is thereby rotatable about the axis of rotation 15 in the second direction of rotation relative to the housing 10.

[0031] Preferably, it is provided that in the closed state of the coupling device 21, the first element 12 is connected to the second element 13 in a rotationally fixed manner by means of the coupling device 21, also in the first direction of rotation, so that in a further overrun operation of the motor vehicle by means of the vehicle wheels 3 and 4, the second element 13 can be driven and is therefore rotatable about the axis of rotation 15 in the first direction of rotation relative to the housing 10, whereby in the further overrun operation, the first element 12 can be driven by the second element 13 via the coupling device 21 and is therefore rotatable about the axis of rotation 15 in the first direction of rotation relative to the housing 10.Thus, for example, in the further coasting mode, the motor vehicle rolls forward in the longitudinal direction of the motor vehicle, so that, for example, in the further coasting mode, the respective vehicle wheel 3, 4 rotates about the respective wheel rotation axis of the respective vehicle wheel 3, 4 in the respective first wheel rotation direction, in particular relative to the housing 10. When reversing, however, the respective vehicle wheel 3, 4 rotates about the respective wheel rotation axis of the respective vehicle wheel 3, 4 in the respective second wheel rotation direction, in particular relative to the housing 10. If the drive motor 6 causes the forward travel, the drive device 1 is in a first traction mode, in which the drive motor 6 drives the vehicle wheels 3 and 4 and thereby causes the forward travel.If the drive motor 6 causes the motor vehicle to travel backwards, the drive device 1 is in a second traction mode, in which the drive motor 6 drives the vehicle wheels 3 and 4 and thereby causes the motor vehicle to travel backwards. In the first overrun mode and in the further overrun mode, the drive motor 6 does not drive the vehicle wheels 3, 4, whereby in the first overrun mode the vehicle wheels 3 and 4 do not drag the drive motor 6. This allows for particularly efficient operation. In the further overrun mode the vehicle wheels 3 and 4 drag the drive motor 6, whereby the drive motor 6 can be driven or is driven.As a result, for example, the electric machine can be operated in generator mode and thus as a generator, by means of which kinetic energy of the motor vehicle, in particular a vehicle rolling forward, can be or is converted into electrical energy, which can be or is provided by the generator. The electrical energy provided by the generator can, for example, be stored at least temporarily, in particular electrochemically, in an electrical energy storage device of the motor vehicle.

[0032] It can be seen that the coupling device 21 is arranged outside the freewheel 18, which is arranged outside the coupling device 21. In addition, in the Fig. 1, it is provided that the coupling device 21 and the freewheel 18 follow one another along the axis of rotation 15 and thus in the axial direction of the drive device 1.

[0033] In the Fig. 1, the coupling device is designed as a positive coupling device, in particular as a claw coupling, wherein by means of the positive coupling device, in particular by means of the claw coupling, the first element 12 is connected in the closed state in a form-fitting, rotationally fixed manner to the second element 13 in the second direction of rotation.

[0034] The drive device 1 also has a bearing, in this case designed as a rolling bearing 22, which is formed, for example, separately from the elements 12 and 13. In this case, the rolling bearing 22 is arranged coaxially with the elements 12 and 13. By means of the rolling bearing 22, which is arranged in the radial direction of the respective element 12, 13 between respective partial regions of the elements 12 and 13, the elements 12 and 13 are rotatably mounted to one another. The respective radial direction of the respective element 12, 13 runs perpendicular to the axis of rotation 15. List of reference symbols 1 drive device 2 vehicle axles 3 vehicle wheel 4 vehicle wheel 5 double arrow 6 Drive engine 7 Stator 8 Rotor 9 Machine rotation axis 10 housings 11 Transmission path 12 first element 13 second element 14 Gearing 15 axis of rotation 16 Arrow 17 Arrow 18 Freewheel 19 Freewheel element 20 freewheel element 21 Coupling device 22 rolling bearings S1 page S2 page QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2008 015 225 A1

[0002] US 10 233 977 B2

[0002] DE 10 2019 214 131 A1

[0002] CN 107914562 B

[0002]

Claims

[1] Drive device (1) for a motor vehicle, with at least one vehicle axle (2) which has two vehicle wheels (3, 4), with at least one drive motor (6), with a transmission path (11) via which the vehicle wheels (3, 4) can be driven by means of the drive motor (6), and with a freewheel (18) arranged in the transmission path (11) between two elements (12, 13) of the transmission path (11) which can be driven by the drive motor (6) and are thereby rotatable, characterized by a coupling device (21) provided in addition to the freewheel (18), which can be switched between: - an open state in which: ◯ a first of the elements (12, 13) is connected to the second element (13) in a rotationally fixed manner, with respect to the freewheel (18) and the coupling device (21), exclusively by means of the freewheel (18) in a first direction of rotation (16) extending about a rotational axis (15) about which the first element (12) is rotatable, so that in order to effect forward travel of the motor vehicle by means of the drive engine (6), the first element (12) can be driven and thereby rotated about the rotational axis (15) in the first direction of rotation (16), whereby in order to effect forward travel, the second element (13) can be driven by the first element (12) via the freewheel (18) and thereby rotated; and ◯ the freewheel (18) and the coupling device (21) permit a rotation of the first element (12) in a second direction of rotation (17) opposite to the first direction of rotation (16), extending around the axis of rotation (15) and relative to the second element (13), so that in overrun mode of the motor vehicle, the second element (13), which is driven by the vehicle wheels (3, 4) and thus rotates, does not drive the first element (12) via the freewheel (18) and rotates it in the first direction of rotation (16); and - a closed state in which the first element (12) is connected to the second element (13) in a rotationally fixed manner in the second direction of rotation (17) by means of the coupling device (21), so that in order to effect reverse travel of the motor vehicle by means of the drive engine (6), the first element (16) can be driven and is thereby rotatable about the axis of rotation (15) in the second direction of rotation (17), whereby in order to effect reverse travel the second element (13) can be driven by the first element (12) via the coupling device (21) and is thereby rotatable. [2] Drive device (1) according to claim 1, characterized byin that in the closed state the first element (12) is connected to the second element (13) in a rotationally fixed manner by means of the coupling device (21) also in the first direction of rotation (16), so that in a further overrun operation of the motor vehicle by means of the vehicle wheels (3, 4) the second element (17) can be driven and thereby rotated, whereby in the further overrun operation the first element (12) can be driven by the second element (13) via the coupling device (21) and thereby rotated about the axis of rotation (15) in the first direction of rotation (16). [3] Drive device (1) according to claim 1 or 2, characterized by that the coupling device (21) is arranged outside the freewheel (18), which is arranged outside the coupling device (21). [4] Drive device (1) according to claim 3, characterized by that the coupling device (21) and the freewheel (18) follow one another when viewed along the axis of rotation (15). [5] Drive device (1) according to one of the preceding claims, characterized by that the coupling device (21) is designed as a positive-locking coupling device, by means of which, in the closed state, the first element (12) is connected to the second element (13) in a form-fitting, rotationally fixed manner in the second direction of rotation (17). [6] Drive device (1) according to one of the preceding claims, characterized by that the drive machine (6) is designed as an electrical machine which has a stator (7) and a rotor (8) which can be driven by means of the stator (7) and is thereby rotatable about a machine rotation axis (9) relative to the stator (7), wherein: - to effect forward travel by means of the rotor (8), the first element (12) is drivable and thereby rotatable about the axis of rotation (15) in the first direction of rotation (16); and - to effect reverse travel, the first element (12) can be driven by means of the rotor (8) and can thereby be rotated about the axis of rotation (15) in the second direction of rotation (17). [7] Motor vehicle, with a drive device (1) according to one of the preceding claims.

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