Distribution device for distributing drive power with a locking device and a stepped ring gear as well as an electric axle drive device

Abstract

Distribution device (1) for distributing drive power to several vehicle wheels (F1, F2) of an electric vehicle comprising: - a power input (2) which can be connected to a drive (30), - a first and a second power output (3, 4) which can be connected to vehicle wheels (F1, F2), - a distribution gear stage (5) for splitting and distributing drive power from the power input (2) to the first and second power output (3, 4), - a transmission gear stage (6) for transmitting drive power from the distribution gear stage (5) to the second power output (4), - the distribution device (1) comprising a torque-sensing locking device (18) which is designed such that the torque input at the power input (2) determines the locking effect of the locking device (18) between the first and second power output (3, 4), characterized in that - the transmission gear stage (6) comprises a stepped ring gear (7),- wherein the stepped ring gear (7) comprises a first ring gear (8) and a second ring gear (9),- wherein the first ring gear (8) and the second ring gear (9) have different diameters,- wherein the first ring gear (8) has internal teeth, and- wherein the second ring gear (9) has internal teeth.

Description

The invention relates to a distributing device for distributing a drive power to a plurality of vehicle wheels of an electric vehicle and to an electric final drive device for driving a plurality of vehicle wheels of an electric vehicle.From the prior art electrically operated vehicles are known which have an electric motor for driving vehicle wheels. In this case, an electric motor is generally connected to a differential or to a distribution device in order, for example, to drive two vehicle wheels with an electric motor. Such a differential has two planetary gears. One for distributing power to first and second vehicle wheels, the first planetary gear set being connected to the first vehicle wheel, and one for transmitting from the one planetary gear set having the power distribution toward the second vehicle wheel.DE 10 2019 216 510 A1 shows a transmission comprising an input shaft, a first output shaft, a second output shaft, a first planetary gear set and a second planetary gear set connected to the first planetary gear set, wherein the planetary gear sets each comprise a plurality of elements, wherein the input shaft is connected in a rotationally fixed manner to a first element of the first planetary gear set, the first output shaft is connected in a rotationally fixed manner to a second element of the first planetary gear set, the second output shaft is connected in a rotationally fixed manner to a third element of the second planetary gear set, a third element of the first planetary gear set is connected in a rotationally fixed manner to a first element of the second planetary gear set via a shaft, and a second element of the second planetary gear set is fixed to a rotationally fixed component.In view of the foregoing, it is an object of the present invention to increase the range of an electric powered vehicle and improve the efficiency of combining an electric motor with a differential.This object is achieved by the features of the independent claims. Further advantageous developments are the subject matter of the dependent claims.A first aspect of the present invention includes a distribution device for distributing a driving power to a plurality of vehicle wheels of an electric vehicle. The distributing device can be used to distribute an incoming torque, for example, incoming at a power input, to equal parts on two vehicle wheels or on two power outputs.The distribution device comprises a power input which can be connected to an electric drive, and a first and a second power output which can be connected to vehicle wheels.Furthermore, the distributing device has a distributing transmission stage for branching and distributing a drive power from the power input to the first and second power output. The distribution gear stage can be designed such that it can output power to a vehicle wheel. The distribution gear stage can comprise a planetary gear.In addition, the distribution device comprises a transmission gear stage for transmitting drive power from the distribution gear stage to the second power output.According to the invention, a stepped ring gear has a first ring gear and a second ring gear. The first ring gear and the second ring gear may have different diameters. The pitch circle diameter of the second ring gear can also be greater than the pitch circle diameter of the first ring gear. The stepped ring gear can also be formed in one piece.Furthermore, the first ring gear can have an internal toothing and / or a first pitch circle diameter. In addition, the second ring gear can have an internal toothing and / or a second pitch circle diameter. The first pitch circle diameter may be smaller than the second pitch circle diameter.In addition, the distribution device has a torque-sensing locking device which is designed such that the torque arriving at the power input determines the locking effect of the locking device between the first and second power outputs, in order to change the traction of vehicle wheels, for example. Torque can also be distributed or conducted thereby from the first to the second power output and / or vice versa. Furthermore, torque can thus be transmitted or distributed at least partially directly from the first to the second power output or vice versa. By means of the locking device, which can be arranged between the first and second power outputs, a locking effect of the locking device between the first and second power outputs can be achieved, which e.g. changes the traction in the case of friction differences of vehicle wheels. This is because coupling the two power outputs makes it possible to conduct or shift torque from one power output to the other power output.The term "blocking effect" can be understood, for example, in the present context such that an axial contact pressure force, by which first and second power outputs can be connected to one another, can be proportional from the first power output in the direction of the second power output and / or vice versa as a function of the incoming load (e.g. represented by the incoming torque at the power input) and / or can be generated automatically. It is further noted that e.g. the locking action in a locked state may be 100%; i.e. the vehicle wheels are rigidly coupled and rotate at the same speed. The opposite may also be the case. Furthermore, states between 0 and 100 percent are also possible.The torque-sensing locking device can be designed such that the locking effect of the locking device between the first and second power outputs increases or decreases, for example in proportion, with the torque arriving at the power input.Also, the torque sensing locking device may be configured such that the higher an input torque from the power input, the higher the locking action of the locking device between the first and second power outputs, and the lower an input torque from the power input, the lower the locking action of the locking device between the first and second power outputs.In addition, it is possible for the torque-sensing locking device to be designed to partially to completely frictionally connect the first power output to the second power output and / or to partially to completely or partially or at least partially or not completely and / or completely release the frictional engagement between the two power outputs.Furthermore, the torque sensing locking device may be configured to enable continuously connecting and disconnecting first and second power outputs. Thus, the locking effect of the locking device can be determined continuously, for example between 0 and 100 percent, from the incoming torque.The torque sensing locking device may comprise first and second friction plates which may be movable towards and away from each other.Thus, the first friction disk can be connected, for example, in a torque-transmitting or torque-proof manner, to the first power output or to a planet carrier of a planetary gear of the distribution gear stage.In this case, the first friction disk can be arranged at the first power output or at a planet carrier of a planetary gearing of the distribution transmission stage, for example in a torque-transmitting or rotationally fixed manner.Furthermore, a planet carrier of a planetary gear of the distributing transmission stage can be connected to the first power output in a rotationally fixed manner. Additionally or alternatively, the planet carrier can function as a first power output.Furthermore, it is possible for the second friction disk to be connected, for example in a torque-transmitting or rotationally fixed manner, to the second power output or to a spur gear of the transmission transmission stage.The second friction disk may be arranged at the second power output or at a spur gear of the transmission gear stage, for example in a torque-transmitting or rotationally fixed manner.Furthermore, a spur gear of the transmission gear stage can be connected to the second power output in a rotationally fixed manner. Additionally or alternatively, the spur gear can function as a second power output.In addition, it can be provided that the first and second friction disks are movable relative to one another in the axial direction or in the direction of the axes of rotation of the first power output and / or of the second power output.In addition, it may be possible for the first friction disk to be designed to be movable in the axial direction relative to the first power output and / or to the second power output. Consequently, for example, a relative movement between the first power output and the first friction disc in the axial direction is possible.The first friction plate may be rigidly connected to the first power output in the axial direction. In other words, the first friction disc can be formed together with the first power output in an axially movable manner relative to the second power output. Thus, for example, a relative movement between the first power output and the first friction disk in the axial direction is not possible.Furthermore, it can be provided that the second friction disk is designed to be movable in the axial direction relative to the second power output and / or to the first power output. In this way, for example, a relative movement between the second power output and the second friction disk in the axial direction is possible.The second friction plate may be rigidly connected to the second power output in the axial direction. In other words, the second friction disc can be formed together with the second power output so as to be movable in the axial direction relative to the first power output. Consequently, for example, a relative movement between the second power output and the second friction disc in the axial direction is therefore not possible.Each of the first and second friction plates may include a friction facing that may resist relative rotation of the two friction plates. With the aid of a friction disk, the locking effect of the locking device can also be adjusted. In this case, for example, the frictional resistance increases in proportion to the pressure at which the first friction disk is pressed against the second friction disk.Furthermore, the transmission gear stage can have a stepped ring gear. Thus, an increase in the transmission ratio in the distribution device or in a rolling differential beyond the limits of the arrangement with two planetary gear sets, as solutions of the prior art provide, can be achieved. In addition, weight can be saved and the efficiency of an electric final drive device can be improved.In other words, the stepped ring gear can form an axial offset device in order to compensate for an axial offset between the first and second power outputs, for example on account of the transmission gear stage being formed as a spur gear stage. Such an axial offset device may be necessary, for example, if the distribution gear stage is realized as a planetary gear or has a planetary gear and the transmission gear stage is realized as a spur gear stage. The axle offset device can conduct a drive power from the transmission gear stage to the second power output and thus to a vehicle wheel or to a second vehicle wheel. In this case, the axle offset device formed with the stepped ring gear transmits rotational speed and torque of the transmission transmission stage to the second power output. The axle offset device or the stepped ring gear allows the rotational speed and / or the torque to be output from the transmission transmission stage unchanged or 1:1 to the second power output. Mechanical losses can be taken into account and partially compensated for when selecting the transmission ratio.In other words, the distribution device or the transmission gear stage can have a stepped ring gear in order to compensate for an offset or an axial offset between the first and second power outputs. For forming a common vehicle axle, it may be necessary, due to the configuration of the transmission gear stage, e.g. as a spur gear stage for driving a vehicle wheel in combination with the distribution gear stage for driving a further vehicle wheel, to select the transmission ratio of the gear stages for both vehicle wheels such that, e.g. when driving straight ahead, the rotational speeds of the first and second power output are identical. This can result in the fact that the transmission gear stage and the distribution gear stage have an axial offset which must be compensated precisely by means of the axial offset device or by means of the stepped ring gear.In addition, the transmission gear stage can be designed as a spur gear stage. The transmission gear stage may include a spur gear in addition to the stepped ring gear. The spur gear may mesh with the first ring gear of the stepped ring gear. In addition, the spur gear and the first ring gear can be formed in a helical gear. The spur gear can also be mounted movably in the axial direction, which is aligned identically to the axis of rotation of the spur gear.Also, in the axial direction, which is oriented identically to the axis of rotation of the spur gear, a second friction disk of the locking device can be formed or mounted so as to be movable relative to the spur gear. In this case, the friction disc can be formed obliquely toothed with the spur wheel.The helical gearing between spur gear and ring gear or between spur gear and second friction disk leads to higher radial and axial forces with an increasing torque. The axial forces may move the second friction plate alone or together with the spur gear towards the first friction plate. Thus, the higher the incoming torque, the higher the axial forces resulting from the helical gearing; and thus, as the torque increases, the second friction plate can be pressed toward the first, with a higher force proportional to the torque. As torque decreases, the second friction plate may move in an opposite direction to the first friction plate. Thus, the lower the incoming torque, the lower the axial forces resulting from the helical gearing that can cause a locking action.The spur gear can have an external toothing. The first ring gear of the stepped ring gear may have an internal toothing. A spur gear stage can thus be formed or a spur gear transmission can be realized with a spur gear and a first ring gear of the stepped ring gear. The axes of rotation of the spur gear and the stepped ring gear may be offset and / or spaced apart from each other. Compared to the prior art, which uses a planetary gear at this point, this solution is lighter and more cost-effective since it has fewer components.Furthermore, the distribution gear stage can comprise a planetary gear. The planetary gear may include a ring gear. In this case, the ring gear of the planetary gearing of the distributing transmission stage and the stepped ring gear of the transmission transmission stage or the second ring gear of the stepped ring gear of the transmission transmission stage can be connected to one another in a rotationally fixed manner or can be formed in one piece. This symbiosis of the ring gears provides a simple construction of the distributing device and at the same time an optimized weight compared to solutions from the prior art.The planetary gear may include a sun gear, first planets, a planet carrier, and a ring gear. The planetary gear can also have second planets and third planets. In this case, the first, second and / or third planets can be rotatably arranged on the planet carrier. Further, the first planets may, e.g., only, mesh with the sun gear. Also, the second planets may, for example, only mesh with the first or the third planets.Furthermore, the first, second and third planets as well as the ring gear and the sun gear can be formed in a helical gear. In this case, the planet carrier can be mounted movably in the axial direction, which is aligned identically to the axis of rotation of the planet carrier.In addition, it is possible that in the axial direction, which is oriented identically to the axis of rotation of the planetary carrier, a first friction disk of the locking device is formed or mounted so as to be movable relative to the planetary carrier. In this case, the first friction disc can be formed obliquely toothed with the planet carrier.The helical gearing between the planet carrier and the sun gear, the first, second and third planets or between the planet carrier and the first friction disc leads to higher radial and axial forces with an increasing torque. The axial forces may move the first friction plate alone or together with the planet carrier towards the second friction plate. Thus, the higher the incoming torque, the higher the axial forces resulting from the helical gearing; and thus, as the torque increases, the first friction plate can be forced toward the second, with a higher force proportional to the torque. As torque decreases, the first friction plate may move in an opposite direction to the second friction plate. Thus, the lower the incoming torque, the lower the axial forces resulting from the helical gearing that can cause a locking action.In addition, the first and second planets can be rotatable about a common axis of rotation and / or can be connected to one another in a rotationally fixed manner. The first and second planets may form a stepped planetary set. The third planets may be meshed with the second planets and the ring gear. By means of this configuration, a drive power or rotational speed and / or torque can be distributed from the distribution transmission stage to a first vehicle wheel and also to the transmission transmission stage and thus to a second vehicle wheel. Precisely speaking, a power split can thus be effected via the distributing transmission stage to the planet carrier and to the ring gear which drives the transmitting transmission stage.The first, second and / or third planets can have different and / or partially also the same pitch circle diameters in order to generate a definable transmission ratio. The pitch circle diameter of the first planets may be greater than the pitch circle diameter of the second and / or third planets. The pitch circle diameter of the second planets can also be greater or smaller than the pitch circle diameter of the third planets. Further, the pitch circle diameter of the second planets and third planets may be the same. In this way, a further transmission ratio can be created within the planetary gearing of the distribution gear stage with the aid of the second and third planets. This in combination with the spur gear of the transmission gear stage creates, in total, a weight-optimized solution for an electric final drive device.Furthermore, the sun wheel can be connected to the power input in a rotationally fixed manner or can be formed in one piece.The planet carrier can also be connected in a rotationally fixed manner to the first power output and / or to the locking device. The planet carrier can function as a first power output.Furthermore, the distribution device can be designed as a rolling differential. In addition, the distribution device can be a spur gear differential or can be designed as such.Furthermore, the first and second power outputs can each be formed by a shaft or respectively by an axis which can be aligned in the same orientation with respect to one another. The first and second power outputs may be coaxially aligned.A second aspect of the present invention includes an electric final drive device for driving a plurality of vehicle wheels of an electric vehicle.It is expressly pointed out that the features of the distribution device as mentioned under the first aspect can be used individually or combined with one another in the electric final drive device.In other words, the features mentioned above under the first aspect of the invention relating to the distribution device can also be combined here under the second aspect of the invention with further features.An electric final drive device for driving a plurality of vehicle wheels of an electric vehicle comprises a distribution device according to the first aspect.Furthermore, the electric final drive device has at least one electric drive or an electric motor which is arranged coaxially with the first and / or second power output of the distribution device. A shaft of the at least one electric drive can form the power input of the distribution device.Furthermore, a shaft of the at least one electric drive can be connected in a rotationally fixed manner or formed in one piece with a sun wheel of a planetary gearing of the distribution gear stage of the distribution device. The electric drive can thus easily form a power input for the distribution device.The concept of the invention presented above is expressed in other words again and additionally below.This concept relates--shown in simplified form--to a rolling differential or a distributing device with focus on the so-called E-axis.Rolling differentials or distributing devices known hitherto are designed on the basis of two planetary gear sets or two planetary gear sets and have limitations with respect to the total transmission ratio.To solve this problem, a second planetary gear can be replaced by a spur gear with stepped ring gear for the transmission ratio increase in the rolling differential. In this case, the coupling of a distribution gear stage of the distribution device to a transmission gear stage of the distribution device can be realized via the stepped ring gear and via an intermediate gear or a further planetary gear in the distribution gear stage, which can span an axle triangle with the stepped ring gear and the output spur gear or the spur gear of the transmission gear stage.It is also an object to improve traction in vehicle wheel friction differentials. A blocking device can be used for this purpose. By means of the locking device, which can be arranged between two outputs or between two power outputs, a locking effect can be achieved which improves the traction in the case of friction differences. This is because coupling the two power outputs makes it possible to conduct torque from the more rapidly rotating power output to the more slowly rotating power output.The invention is explained in more detail below on the basis of an exemplary embodiment in conjunction with a drawing. The following is shown schematically: FIG. 1 is a schematic sectional view of an electric final drive device for driving a plurality of vehicle wheels.FIG. 1 shows a schematic sectional view of an electric final drive device 40 for driving a plurality of vehicle wheels F 1, F 2 of an electric vehicle.More specifically, FIG. 1 shows that the electric final drive device 40 comprises a distribution device 1 and an electric drive 30 or an electric motor which is arranged coaxially with a first power output 3 of the distribution device 1.A shaft of the electric drive 30 forms a power input 2 of the distribution device 1, wherein the shaft of the electric drive 30 is connected in a rotationally fixed manner or is formed in one piece with a sun wheel 12 of a planetary gearing 10 of a distribution gear stage 5 of the distribution device 1.Furthermore, FIG. 1 shows a distribution device 1 for distributing a drive power to a plurality of vehicle wheels F 1, F 2 of an electric vehicle.The distribution device 1 has a power input 2 which can be connected to the electric drive 30, and a first and a second power output 3, 4 which are connected to vehicle wheels F 1, F 2.Furthermore, FIG. 1 shows that the distribution device 1 comprises a distribution transmission stage 5 for branching and distributing a drive power from the power input 2 to the first and second power outputs 3, 4.The distribution device 1 also has a transmission gear stage 6 for transmitting drive power from the distribution gear stage 5 to the second power output 4.It can also be seen from FIG. 1 that the distribution device 1 has a torque-sensing locking device 18. The torque-sensing locking device 18 is designed such that the torque arriving at the power input 2 determines the locking effect of the locking device 18 between the first and second power outputs 3, 4.More specifically, the torque-sensing blocking device 18 is designed such that the blocking effect of the blocking device 18 between the first and second power outputs 3, 4, for example, increases or decreases proportionally with the torque arriving at the power input 2.Thus, the torque-sensing locking device 18 is designed in such a way that the higher an input torque from the power input 2, the higher the locking action of the locking device 18 between first and second power outputs 3, 4 and the lower an input torque from the power input 2, the lower the locking action of the locking device 18 between first and second power outputs 3, 4.In other words, the torque-sensing blocking device 18 is designed to partially to completely connect the first power output 3 to the second power output 4 in a frictional connection and / or to at least partially to completely release the frictional connection between the two power outputs 3, 4.Furthermore, the torque-sensing blocking device 18 is designed such that it enables a continuously variable connection and disconnection of the first and second power outputs 3, 4. Thus, the locking action of the locking device 18 can be determined continuously, for example, between 0 and 100 percent of the incoming torque.As a result, a torque can thus be distributed or conducted from the first to the second power output 3, 4 or vice versa. By means of the blocking device 18, which is arranged between the first and second power outputs 3, 4, a blocking effect of the blocking device 18 between the first and second power outputs 3, 4 can be achieved, which changes the traction in the event of friction differences. This is because coupling the two power outputs 3, 4 makes it possible to conduct or shift torque from one power output to the other power output.Furthermore, FIG. 1 shows that the torque-sensing locking device 18 has a first and a second friction disk 19, 20 which can be moved towards and away from one another.In this case, the first friction disk 19 is connected in a rotationally fixed manner to the first power output 3 or to a planet carrier 16 of a planetary gearing 11 of the distribution transmission stage 5. Described more specifically, the first friction disk 19 is arranged on the first power output 3 or on a planet carrier 16 of a planetary gear 11 of the distribution gear stage 5 in a rotationally fixed manner.The planet carrier 16 is connected in a rotationally fixed manner to the first power output 3, wherein the planet carrier 16 functions as the first power output 3.Furthermore, FIG. 1 shows that the second friction disk 20 is connected in a rotationally fixed manner to the second power output 4 or to a spur gear 10 of the transmission transmission gear stage 6. Described more precisely, the second friction disk 20 is arranged in a rotationally fixed manner on the second power output 4 or on a spur gear 10 of the transmission transmission stage 6.The spur gear 10 is connected to the second power output 4 in a rotationally fixed manner, wherein the spur gear 10 functions as a second power output 4.The first and second friction disks are movable relative to one another in the axial direction A or in the direction of the axes of rotation of the first power output 3 and / or of the second power output 4.In this case, the first friction disk 19 can be designed to be relatively movable in the axial direction A with respect to the first power output 3 and / or the second power output 4.Consequently, it is possible for the first friction disk 19 to be rigidly connected to the first power output 3 in the axial direction A. It is thus possible for the first friction disk 19 to be configured together with the first power output 3 to be movable in the axial direction A relative to the second power output 4.The second friction disk 20 can also be designed to be movable in the axial direction A relative to the second power output 4 and / or to the first power output 3.Accordingly, it is possible for the second friction disk 20 to be rigidly connected to the second power output 4 in the axial direction A. Consequently, it is conceivable that the second friction disk 20 together with the second power output 4 is configured to be relatively movable in the axial direction A relative to the first power output 3.Each friction disc may have a friction lining which can provide a certain resistance to the relative rotation of the two friction discs 19, 20. With the aid of a friction disk, the locking effect of the locking device 18 can also be adjusted. In this case, for example, the frictional resistance increases in proportion to the pressure at which the first friction disk 19 is pressed against the second friction disk 20.In addition, it can be seen from FIG. 1 that the transmission gear stage 6 has a stepped ring gear 7. Thus, an increase in the transmission ratio in the distribution device 1 beyond the limits of the arrangement with two planetary gears (one for the distribution gear stage 5 and one for the transmission gear stage 6) can be achieved, as solutions from the prior art provide. In addition, weight can be saved and the efficiency of the electric final drive device 40 can be improved.In other words, the stepped ring gear 7 forms an axial offset device in order to compensate for an axial offset between the first and second power outputs 3, 4 on account of the transmission gear stage 6 being designed as a spur gear stage. Such an axial offset device may be necessary, for example, if the distribution gear stage 5 is realized as a planetary gear and the transmission gear stage 6 is realized as a spur gear stage. The axle offset device can conduct a drive power from the transmission gear stage 6 to the second power output 4 and thus to the second vehicle wheel F 2. In this case, the axle offset device formed with the stepped ring gear 7 transmits the rotational speed and torque of the transmission gear stage 6 to the second power output 4; the axle offset device or the stepped ring gear 7 allows the rotational speed and the torque to be output from the transmission gear stage 6 unchanged or 1:1 to the second power output 4; mechanical losses are not taken into account.In other words, the distribution device 1 or the transmission gear stage 6 has a stepped ring gear 7 in order to compensate for an offset or an axial offset between the first and the second power output 3, 4. For in order to form a common vehicle axle, it may be necessary, due to the configuration of the transmission gear stage 6-as will be explained below-as a spur gear stage for driving a vehicle wheel F2 in combination with the distribution gear stage 5 for driving a further vehicle wheel F1-to choose the transmission ratio of the gear stages for both vehicle wheels F1, F2 in such a way that, for example, during straight-ahead travel, the rotational speeds of the first and second power outputs 3, 4 are identical. This can result in the circumstance that the transmission gear stage 6 and the distribution gear stage 5 have an axial offset which must be compensated precisely by means of the stepped ring gear 7.In this case, according to FIG. 1, the stepped ring gear 7 has a first ring gear 8 and a second ring gear 9. In other words, the pitch circle diameter of the second ring gear 9 is greater than the pitch circle diameter of the first ring gear 8, the stepped ring gear 7 being formed in one piece.Further, the first ring gear 8 has internal teeth and a first pitch circle diameter. In addition, the second ring gear 9 has an internal toothing and a second pitch circle diameter. As already mentioned, the first pitch circle diameter is smaller than the second pitch circle diameter (cf. FIG. 1 ).In addition, FIG. 1 shows that the transmission gear stage 6 is designed as a spur gear stage. Thus, an increase in the transmission ratio in the distribution device 1 beyond the limits of the arrangement with two planetary gears, one per gear stage, as solutions from the prior art provide, can be achieved. Moreover, this solution allows weight to be saved and the efficiency of an electric drive to be improved.Described more specifically, the transmission gear stage 6 includes a spur gear 10 in addition to the stepped ring gear 7, the spur gear 10 meshing with the first ring gear 8 of the stepped ring gear 7. In this case, the first ring gear 8 has an internal toothing and the spur gear 10 an external toothing, wherein the spur gear 10 and the first ring gear 8 are formed in a helical manner. Thus, a spur gear stage can be formed or a spur gear transmission with a spur gear and a first ring gear 8 of the stepped ring gear 7 can be realized. This solution uses few components and is consequently weight-saving. Further, the rotation axes of the spur gear 10 and the stepped ring gear 7 are offset or spaced apart from each other.Although it is not shown in FIG. 1, it is nevertheless possible for the spur gear 10 to be mounted movably in the axial direction A, which is oriented identically to the axis of rotation of the spur gear 10. Also, in the axial direction A, which is oriented identically to the axis of rotation of the spur gear 10, the second friction disk 20 of the locking device 18 can be formed or mounted so as to be relatively movable with respect to the spur gear 10. Here, the friction disc 20 can be formed obliquely toothed with the spur wheel 10.The helical gearing between spur gear 10 and ring gear 8 or between spur gear 10 and second friction disk 20 leads to higher radial and axial forces with an increasing torque. The axial forces move the second friction disc 20 alone or together with the spur gear 10 towards the first friction disc 19, i.e. the higher the incoming torque, the higher the axial forces resulting from the helical gearing; and thus, as the torque increases, the second friction disc 20 is pressed towards the first, with a higher force proportional to the torque. As the torque decreases, the second friction disk 20 moves in the opposite direction to the first friction disk 19.As can be seen in FIG. 1, the distribution gear stage 5 comprises a planetary gear 11 which has a ring gear 17. The ring gear 17 of the planetary gear 11 of the distributing gear stage 5 and the stepped ring gear 7 of the transmission gear stage 6 or the second ring gear 9 of the stepped ring gear 7 of the transmission gear stage 6 are connected to one another in a rotationally fixed manner or are formed in one piece. This symbiosis of the ring gear 17 of the planetary gearing 11 and of the first and second ring gears 8, 9 of the stepped ring gear 7 creates a simple construction of the distribution device 1 and at the same time an optimized weight compared to solutions from the prior art.As can further be seen from FIG. 1, the planetary transmission 11 comprises a sun gear 12, first planets 13, second planets 14 and third planets 15, a planet carrier 16 and the ring gear 17.Further, the first planets 13 are meshed only with the sun gear 12, and the second planets 14 are meshed only with the third planets 15. The first, second and third planets 13, 14, 15 and the ring gear 17 and the sun gear 12 are formed in helical gear.Furthermore, the first and second planets 13, 14 are rotatably and rotationally fixedly connected to one another about a common axis of rotation, wherein the first and second planets 13, 14 form a stepped planetary set. The third planets 15 mesh or are in engagement with the second planets 14 and the ring gear 17 or with the transmission gear stage 6. Precisely speaking, power is split via the distributing transmission stage 5 to the planet carrier 16 and the ring gear 17 or to the transmitting transmission stage 6.In addition, FIG. 1 shows that the first, second and third planets 13, 14, 15 have different and in some cases also the same pitch circle diameters in order to generate a definable transmission ratio. Here, the pitch circle diameter of the first planets 13 is larger than the pitch circle diameter of the second and third planets 14, 15. In this way, a further transmission ratio can be created within the planetary gear 11 of the distribution gear stage 5 with the aid of the second and third planets 14, 15. This in combination with the spur gear 10 of the transmission gear stage 6 creates, in total, a weight-optimized solution for the electric final drive device 40.Furthermore, FIG. 1 shows that the sun gear 12 is connected to the power input 2 in a rotationally fixed manner or is formed in one piece.The planet carrier 16 is connected in a rotationally fixed manner to the first power output 3 and to the blocking device 18, wherein the planet carrier 16 functions precisely as the first power output 3.In summary, it can be stated that the distribution device 1 is designed as a rolling differential or that the distribution device 1 is a spur gear differential.Although it is not shown in FIG. 1, it is nevertheless possible for the planet carrier 16 to be mounted movably in the axial direction A, which is oriented identically to the axis of rotation of the planet carrier 16. In the axial direction A, which is oriented identically to the axis of rotation of the planet carrier 16, the first friction disk 19 of the locking device 18 can also be formed or mounted so as to be movable relative to the planet carrier 16. In this case, the first friction disc 19 can be formed obliquely toothed with the planet carrier 16.The helical gearing between planet carrier 16 and sun gear 12, first, second and third planets 13, 14, 15 or between planet carrier 16 and first friction disk 19 leads to higher radial and axial forces with an increasing torque. The axial forces move the first friction disc 19 alone or together with the planet carrier 16 in the direction of the second friction disc 20, i.e. the higher the incoming torque the higher the axial forces resulting from the helical gearing; and thus, as the torque increases, the first friction disc 19 is pressed in the direction of the second friction disc 20, namely with a higher force proportional to the torque. As the torque decreases, the first friction disc 19 moves in the opposite direction to the second friction disc 20.Finally, it should be noted that the first and second power outputs 3, 4 are each formed by a shaft or respectively by an axis which are aligned in the same orientation with respect to one another. Specifically, the first and second power outputs 3, 4 are coaxially aligned.List of reference characters1 Distribution device 2 Power input 3 First power output 4 Second power output 5 Distribution transmission stage 6 Transmission transmission transmission stage 7 Stepped ring gear 8 First ring gear 9 Second ring gear 10 Spur gear 11 Planetary gear 12 Sun gear 13 First planet 14 Second planet 15 Third planet 16 Planet carrier 17 Ring gear 18 Locking device 19 First friction disk 20 Second friction disk 30 Drive 40 Final drive device F 1 Vehicle wheel F 2 Vehicle wheel

Claims

Distribution device (1) for distributing a drive power to a plurality of vehicle wheels (F1, F2) of an electric vehicle, having: - a power input (2) which can be connected to a drive (30), - a first and a second power output (3, 4) which can be connected to vehicle wheels (F1, F2), - a distribution transmission stage (5) for branching off and distributing a drive power from the power input (2) to the first and second power outputs (3, 4), - a transmission transmission stage (6) for transmitting drive power from the distribution transmission stage (5) to the second power output (4), - the distribution device (1) has a torque-sensing locking device (18) which is designed such that the torque arriving at the power input (2) determines the locking effect of the locking device (18) between the first and second power outputs (3, 4), characterized in that - the transmission gear stage (6) has a stepped ring gear (7), - wherein the stepped ring gear (7) comprises a first ring gear (8) and a second ring gear (9), - wherein the first ring gear (8) and the second ring gear (9) have different diameters, - wherein the first ring gear (8) has an internal toothing, and - wherein the second ring gear (9) has an internal toothing.Distribution device according to Claim 1, - wherein the torque-sensing blocking device (18) is designed such that the blocking effect of the blocking device (18) increases or decreases between the first and the second power output (3, 4) with the torque arriving at the power input (2), and / or - wherein the torque-sensing blocking device (18) is designed to connect the first power output (3) to the second power output (4) partially to completely in a frictionally locking manner and / or to at least partially to completely release the frictionally locking connection between the two power outputs (3, 4).Distribution device according to Claim 1 or 2, - wherein the torque-sensing blocking device (18) has a first and a second friction disc (19, 20) which can be moved towards and away from one another. - wherein the first friction disc (19) is connected in a rotationally fixed manner to the first power output (3) or to a planet carrier (16) of a planetary gearing (11) of the distribution gearing stage (5), - wherein the second friction disc (20) is connected in a rotationally fixed manner to the second power output (4) or to a spur gear (10) of the transmission gearing stage (6), and - wherein the first and second friction discs (19, 20) can be moved relative to one another in the axial direction (A) or in the direction of the axes of rotation of the first power output (3) and / or of the second power output (4).Distribution device according to Claim 3, - wherein the first friction disc (19) is designed to be movable in the axial direction (A) relative to the first power output (3) and / or to the second power output (4), and / or - wherein the second friction disc (20) is designed to be movable in the axial direction (A) relative to the second power output (4) and / or to the first power output (3).Distribution device according to Claim 1, - wherein the transmission gear stage (6) is designed as a spur gear stage, - wherein the transmission gear stage (6) comprises, in addition to the stepped ring gear (7), a spur gear (10), - wherein the spur gear (10) meshes with a first ring gear (8) of the stepped ring gear (7), - wherein the spur gear (10) and the first ring gear (8) are designed to be obliquely toothed, - wherein the spur gear (10) is mounted movably in the axial direction, which is aligned identically to the axis of rotation of the spur gear (10), and / or - wherein a second friction disc (20) of the locking device (18) is designed or mounted movably relative to the spur gear (10) in the axial direction, which is aligned identically to the axis of rotation of the spur gear (10).Distribution device according to either of Claims 1 and 5, - wherein the distribution transmission stage (5) comprises a planetary transmission (11), - wherein the planetary transmission (11) has a ring gear (17), and - wherein the ring gear (17) of the planetary transmission (11) of the distribution transmission stage (5) and the stepped ring gear (7) of the transmission transmission stage (6) or the second ring gear (9) of the transmission transmission stage (6) are connected to one another in a rotationally fixed manner.Distribution device according to one of Claims 3 to 6, - wherein the planetary transmission (11) has a sun wheel (12), first planets (13), second planets (14) and third planets (15), a planet carrier (16) and a ring gear (17), - wherein the first, second and third planets (13, 14, 15) are rotatably arranged on the planet carrier (16), - wherein the first, second and third planets (13, 14, 15) and the ring gear (17) and the sun gear (12) are formed in helical gearing, and - wherein the planet carrier (16) is mounted movably in the axial direction (A) which is aligned identically to the axis of rotation of the planet carrier (16), and / or - wherein a first friction disc (19) of the locking device (18) is formed or mounted movably relative to the planet carrier (16) in the axial direction (A) which is aligned identically to the axis of rotation of the planet carrier (16).Distribution device according to Claim 7, - wherein the sun wheel (12) is connected in a rotationally fixed manner to the power input (2) or is formed in one piece, and - wherein the planet carrier (16) is connected in a rotationally fixed manner to the first power output (3) and / or to the blocking device (18).An electric final drive device (40) for driving a plurality of vehicle wheels (F1, F2) of an electric vehicle, comprising: - a distribution device (1) according to one of the preceding claims, and - at least one electric drive (30) which is arranged coaxially with the first and / or second power output (3, 4) of the distribution device (1), - wherein a shaft of the at least one electric drive (30) forms the power input (2) of the distribution device (1).

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