Electric vehicle transmission device

Abstract

The invention relates to an electric vehicle transmission (7) having a drive shaft (10), an output shaft (11) and a first planetary gear set (P1), a second planetary gear set (P2) and a third planetary gear set (P3). The drive shaft (10) is provided for coupling with an electric machine (6). The first planetary gear set (P1), the second planetary gear set (P2) and the third planetary gear set (P3) respectively have a first element, a second element and a third element in the form of a sun gear, a planet carrier and a ring gear. A first shifting element (A), a second shifting element and a third shifting element (C) are provided at least functionally. A first element of the first planetary gear set (P1) is connected to the drive shaft (10) in a rotationally fixed manner. In order to achieve the function of a parking lock in the electric vehicle transmission (7), a third shifting element (C) is also provided, by means of which two of the elements of the second planetary gear set or of the third planetary gear set can be connected to each other in a rotationally fixed manner.

Description

Technical Field

[0001] The present invention relates to an electric vehicle transmission device. The electric vehicle transmission device includes a drive shaft, an output shaft, and a first planetary gear set, a second planetary gear set, and a third planetary gear set. Among them, the drive shaft is configured to be coupled to an electric motor. Among them, the first planetary gear set, the second planetary gear set, and the third planetary gear set respectively have a first element, a second element, and a third element in the form of a sun gear, a planet carrier, and a ring gear. Among them, at least functionally, a first shift element, a second shift element, and a third shift element are provided, and among them, the first element of the first planetary gear set is non-rotatably connected to the drive shaft. In addition, the present invention also relates to a drive system, a vehicle drive train, and an electric vehicle. Background Art

[0002] In electric vehicles, an electric vehicle transmission device is partially provided between the respective electric motors and the drive wheels in the respective drive trains of the electric vehicles, so as to, in particular, transmit the driving motion of the electric motor to the drive wheels in a speed-reducing manner. In addition to electric vehicle transmission devices with a single gear ratio, transmission devices in which two or more gear ratios can be switched are also used in electric commercial vehicles.

[0003] DE 10 2017 006 262 A1 shows an electric vehicle transmission device configured for use in an electric vehicle. Here, in addition to the drive shaft and the output shaft, the electric vehicle transmission device further includes three planetary gear sets, each of which is composed of elements in the form of a sun gear, a planet carrier, and a ring gear. Here, in the installed state of the electric vehicle transmission device, the drive shaft is used to connect to an upstream electric motor. In addition, the electric vehicle transmission device further has three shift elements, which are configured as force-locking shift elements, and by selectively operating the shift elements, a force flow guide from the drive shaft via the planetary gear sets to the output shaft with different transmission ratios can be achieved. Summary of the Invention

[0004] Based on the above prior art, the present task of the invention is to provide an electric vehicle transmission device in which different gear ratios can be achieved for the connection of the electric motor, and in which the function of a parking lock should be able to be realized in a simple and compact manner and method via such an electric vehicle transmission device.

[0005] This task is solved based on the preamble of claim 1 in combination with its distinguishing features. The subsequent dependent claims respectively reproduce advantageous improvement solutions of the present invention. In addition, a drive system having an electric vehicle transmission according to the present invention is the subject matter of claims 9 and 10. In addition, claims 11 and 12 relate to a vehicle drive train, and claim 13 relates to an electric vehicle having such a vehicle drive train.

[0006] According to the present invention, an electric vehicle transmission has a drive shaft, an output shaft, and a first planetary gear set, a second planetary gear set, and a third planetary gear set, wherein the drive shaft is arranged for coupling with an electric motor. The first planetary gear set, the second planetary gear set, and the third planetary gear set each have a first element, a second element, and a third element in the form of a sun gear, a planet carrier, and a ring gear, respectively. In addition, at least functionally, a first shifting element, a second shifting element, and a third shifting element are provided. The first element of the first planetary gear set is non-rotatably connected to the drive shaft.

[0007] In the context of the present invention, an "axis" is understood as a rotatable component of the transmission, via which it is possible, if necessary and while simultaneously actuating the respective shifting elements, to guide the force flow between components. Here, the respective axes can connect the components axially or radially, or both axially and radially. Thus, the respective axes can also exist as intermediate members, via which, for example, the respective components are connected radially.

[0008] In the context of the present invention, "axial" refers to the orientation in the direction of the longitudinal central axis of the transmission, and the rotational axes of the rotatable components of the transmission, in particular the axes of the transmission and the elements of the planetary gear sets, are arranged parallel to this longitudinal central axis. Then, "radial" is understood as the orientation in the diameter direction of the respective components of the transmission.

[0009] In the electric vehicle transmission according to the present invention, the drive shaft is arranged for establishing a coupling with the drive side of the electric motor. For this purpose, the drive shaft is in particular equipped with a connection site at which a coupling between the drive shaft and the rotor of the electric motor can be formed. Here, this coupling exists between the electric motor and the drive shaft in such a way that there is always a fixed speed ratio between the rotational speed of the drive shaft of the electric vehicle transmission and the rotational speed of the rotor of the electric motor. Thus, within the scope of the present invention, at least one additional gear ratio stage, for example a cylindrical gear stage and / or a planetary stage, can optionally also be provided between the drive shaft and the rotor of the electric motor, via which a pre-transmission of the rotational movement of the rotor of the electric motor to the drive shaft can be achieved. However, in particular, a non-rotatable connection between the rotor of the electric motor and the drive shaft of the electric vehicle transmission according to the present invention can be achieved, such that the rotor and the drive shaft rotate at the same rotational speed during operation.

[0010] In the electric vehicle transmission according to the invention, the drive shaft and the output shaft are arranged coaxially with each other, in particular, and the planetary gear set can also be placed coaxially with the drive shaft and the output shaft. Thereby, a particularly compact structure of the electric vehicle transmission in the radial direction can be achieved.

[0011] Each planetary gear set is composed of a first element, a second element, and a third element respectively, wherein the elements of each planetary gear set are formed by a sun gear, a planet carrier, and a ring gear respectively. Here, each planetary gear set exists as a negative planetary gear set, in which the respective planet carrier rotatably supports at least one planetary gear, and at least one planetary gear is in tooth engagement with the respective sun gear and with the respective ring gear respectively. In the case where each planetary gear set is implemented as a negative planetary gear set, in particular, the first element is the sun gear, the second element is the planet carrier, and the third element is the ring gear.

[0012] Alternatively, one or more of the planetary gear sets can also be configured as positive planetary gear sets in principle. In this case, at least one planetary gear pair is rotatably supported within the respective planet carrier, and one of the planetary gears in these planetary gears is in tooth engagement with the respective sun gear, and the other planetary gear is in tooth engagement with the respective ring gear. In addition, the planetary gears of at least one planetary gear pair mesh with each other. Different from the embodiment as a negative planetary gear set, the first element of each planetary gear set is the sun gear, the second element of each planetary gear set is the ring gear, and the third element of each planetary gear set is the planet carrier. In addition, compared with the embodiment as a negative planetary gear set, the fixed-axis transmission ratio of each planetary gear set is increased by one. In particular, exactly three planetary gear sets are provided in the electric vehicle transmission according to the invention.

[0013] In addition, the electric vehicle transmission according to the invention also has at least three shift elements functionally, and different gears can be exhibited between the drive shaft and the output shaft by selectively operating the first shift element and the second shift element. Here, in each of these gears, the force flow is guided from the drive shaft via the planetary gear set to the output shaft. Here, at least two gears different in transmission ratio can be exhibited between the drive shaft and the output shaft.

[0014] "Functionally at least" providing the first shift element, the second shift element, and the third shift element means in the sense of the present invention that at least the functions of these three shift elements are embodied in the electric vehicle transmission according to the invention. Here, these three shift elements can specifically exist physically as a single shift element in fact, or their functions can also be embodied by other components, such as a shift device that combines the functions of two or more shift elements.

[0015] The present invention now includes the following technical teachings, namely, the second element of the first planetary gear set is non-rotatably connected to the first element of the third planetary gear set. In addition, the third element of the first planetary gear set is non-rotatably connected to the first element of the second planetary gear set, and the second element of the second planetary gear set is stationary. Similarly, the third element of the third planetary gear set is also stationary. Instead, the second element of the third planetary gear set is non-rotatably connected to the output shaft. The third element of the second planetary gear set can be non-rotatably connected to the second element of the first planetary gear set and the first element of the third planetary gear set via a first shifting element, wherein the third element can also be non-rotatably connected to the second element of the third planetary gear set by means of a second shifting element. In addition, two of the elements of the second planetary gear set or the third planetary gear set can be non-rotatably connected to each other via a third shifting element.

[0016] In the electric vehicle transmission according to the invention, the first element of the first planetary gear set is continuously non-rotatably connected to the drive shaft, whereby the drive shaft and the first element of the first planetary gear set always rotate at the same speed. In addition, the second element of the first planetary gear set is permanently non-rotatably connected to the first element of the third planetary gear set, so that the second element of the first planetary gear set and the first element of the third planetary gear set always rotate at the same speed. Similarly, the third element of the first planetary gear set is also continuously non-rotatably connected to the first element of the second planetary gear set, whereby the third element of the first planetary gear set and the first element of the second planetary gear set also permanently rotate at the same speed. In addition, the second element of the second planetary gear set and the third element of the third planetary gear set are respectively permanently stationary and thus respectively continuously prevent rotational movement. The second element of the third planetary gear set is permanently non-rotatably connected to the output shaft, whereby the output shaft and the second element of the third planetary gear set always rotate at the same speed.

[0017] In the sense of the present invention, the respective permanent non-rotatable connections are each realized via an intermediate shaft, and the intermediate shaft can be present in one piece or in multiple pieces here. In addition, within the scope of the present invention, the following design can also be adopted, in which each shaft is integrally implemented with one or two components non-rotatably connected thereto, and the latter can be achieved especially when the components permanently connected to each other are spatially arranged close to each other.

[0018] In order to achieve permanent immobility, the respective components of the electric vehicle transmission are in particular connected against relative rotation to a permanently immobile structural element, which can be the transmission housing of the electric vehicle transmission, a part of the transmission housing or a component connected against relative rotation to the transmission housing. If necessary, the respective elements of the electric vehicle transmission can also be integrally formed with the permanently immobile structural element.

[0019] Closing the first shift element results in a connection against relative rotation between the third element of the second planetary gear set, the second element of the first planetary gear set, and the first element of the third planetary gear set, whereby the third element of the second planetary gear set, the second element of the first planetary gear set, and the first element of the third planetary gear set rotate together. If the second shift element is transferred to the closed state, the third element of the second planetary gear set is connected against relative rotation to the second element of the third planetary gear set and thus also to the output shaft, so that the third element of the second planetary gear set, the second element of the third planetary gear set, and the output shaft rotate at the same speed.

[0020] In the electric vehicle transmission according to the invention, in addition to the first shift element and the second shift element, a third shift element is provided, which ensures a connection against relative rotation between two elements of the second planetary gear set in the closed state. Alternatively, the third shift element causes a connection against relative rotation between two elements of the third planetary gear set. Thus, actuating the third shift element causes the second planetary gear set or the third planetary gear set to be interlocked. Since the second element of the second planetary gear set is permanently immobile, the interlocking of the second planetary gear set also causes the entire second planetary gear set to be immobile and, in addition, the entire electric vehicle transmission to be immobile. Similarly, in the variant of the invention in which the third shift element connects two elements of the third planetary gear set against relative rotation to each other, the resulting interlocking of the third planetary gear set also achieves the immobility of the entire third planetary gear set and, in addition, the immobility of the electric vehicle transmission, since the third element of the third planetary gear set is permanently immobile.

[0021] The embodiment of the electric vehicle transmission according to the invention has the advantage that, on the one hand, different gears can be switched between the drive shaft and the output shaft via the first shift element and the second shift element, whereby, in the installed state of the electric vehicle transmission, the drive movement of the electric motor can also be transmitted with different transmission ratios. On the other hand, the electric vehicle transmission can be jammed via the third shift element, whereby the function of a parking lock can be achieved. This can be achieved in a simple manner and method here and is achieved with a compact transmission structure.

[0022] According to an embodiment of the present invention, when the third shift element is actuated, the first element of the second planetary gear set is connected to the third element of the second planetary gear set against relative rotation. Alternatively, in the actuated state of the third shift element, the second element of the second planetary gear set is connected to the third element of the second planetary gear set against relative rotation. In both cases, the interlocking of the second planetary gear set is thereby achieved. Since the second element of the second planetary gear set is in a permanently stationary state, this also results in the complete immobility of the second planetary gear set, and thus in the complete immobility of the electric vehicle transmission. Correspondingly, the function of the parking lock of the transmission can thereby be achieved.

[0023] As an alternative or addition to the above embodiment, the shift element is implemented as a form-locking shift element, wherein the shift element can be configured as a non-synchronous dog clutch shift element. The advantage of implementing the shift element as a form-locking shift element is that when the respective shift element is in the disengaged state, little or no drag losses occur at this shift element. Thereby, the efficiency of the electric vehicle transmission can be improved.

[0024] The above variants can be combined with the foregoing embodiments, wherein the first shift element, the second shift element, and the third shift element are formed by a common shift device, and the coupling element of the shift device can be positioned in different shift positions, in which the coupling element functionally represents the actuated state of each of the shift elements in the shift element. Advantageously, the selective actuation of the three shift elements via a common actuator can be carried out, and the coupling element of the actuator transfers one of the shift elements to its actuated state according to the different shift positions. Thereby, the number of components of the electric vehicle transmission can be reduced, and thus the manufacturing cost can also be reduced, and a compact structure can be achieved. This is feasible because in this variant, the third element of the second planetary gear set is always coupled via the coupling element, and a state where two shift elements are simultaneously actuated is not achieved. In one embodiment, in addition to these shift positions, the coupling element can also be positioned in at least one neutral position, in which no anti-relative rotation connection is established via the coupling element.

[0025] However, as an alternative to the above-described design variants, the function of the parking lock implemented via the third shift element can also be achieved in such a way that the first element of the second planetary gear set is non-rotatably connected to the second element of the second planetary gear set via the third shift element, thereby interlocking the second planetary gear set and thus jamming it. However, as a further alternative, in principle, the function of the parking lock can also be achieved in such a way that two of the elements in the third planetary gear set are non-rotatably connected to each other via the third shift element. Thus, the third shift element can non-rotatably connect the first element and the second element, the first element and the third element, or the second element and the third element of the third planetary gear set to each other. In these variants, although the first shift element and the second shift element can be formed by a common shift device having a coupling element, in this case, the third shift element must exist as a single shift element.

[0026] Furthermore, within the scope of the present invention, individual or multiple of the shift elements can be configured as force-locking shift elements, where, in particular, they can exist as diaphragm shift elements in this case. Advantageously, the respective shift elements can thus be actuated under load. In addition, individual or multiple shift elements can also be implemented as form-locking shift elements in the form of locking synchronizers.

[0027] According to a design variant of the present invention, the output shaft is coupled to a differential. Here, the differential is in particular a transverse differential, which is implemented as a bevel gear differential. Here, the drive movement transmitted to the output shaft of the electric vehicle transmission is distributed to the output shafts of the drive axles of the electric vehicle via the transverse differential. In particular, the output shaft of the differential is coupled to the differential housing of the differential here, where this coupling can be achieved in such a way that the output shaft is non-rotatably connected to the differential housing or a cylindrical gear that is in tooth engagement with the crown drive gear of the differential housing is carried. In addition, the differential can also be a longitudinal differential, via which the drive power is distributed to multiple drive axles.

[0028] According to an embodiment of the present invention, the planetary gear sets are arranged in the order of a first planetary gear set, a second planetary gear set, and a third planetary gear set at the connection portion of the drive shaft for coupling the drive shaft to the electric machine. Thus, a suitable structure of the electric vehicle transmission according to the present invention can be achieved. However, within the scope of the present invention, the planetary gear sets can also be arranged differently axially after the connection portion of the drive shaft. In an improved variant of the above embodiment, the first shift element, the second shift element, and the third shift element are also arranged axially between the second planetary gear set and the third planetary gear set.

[0029] In an electric vehicle transmission according to the present invention, the first gear between the drive shaft and the output shaft is obtained by closing a first shift element, and the second gear between the drive shaft and the output shaft can be shifted out by actuating a second shift element. Advantageously, in this way, an appropriate performance of the gears of the electric vehicle transmission is achieved by a corresponding force flow guidance via three planetary gear sets. In addition, the function of the parking lock of the electric vehicle transmission is achieved here in a manner and method according to the present invention by closing a third shift element. By additional shift positioning, additional gears can be achieved. Thus, for example, the second shift element can connect the second and third planetary gear sets in another shift position and thus provide a third gear.

[0030] Furthermore, the subject matter of the present invention is a drive system for an electric vehicle, in which, in addition to an electric motor, there is an electric vehicle transmission according to one or more of the above-mentioned variants. Here, the rotor of the electric motor is coupled to the drive shaft of the electric vehicle transmission, and this coupling exists here in particular as an anti-relative rotation connection between the rotor of the electric motor and the connection site of the drive shaft. Alternatively, one or more intermediate gear ratio stages can also be provided between the drive shaft of the electric vehicle transmission and the rotor of the electric motor, and they can be specifically implemented as spur gear stages or planetary stages here.

[0031] The electric motor of the drive system according to the present invention can be operated here in particular on the one hand as an electric motor and on the other hand as a generator, so as to generate a drive movement for driving the electric vehicle in the former case, while in the latter case, the electric vehicle can be braked (regenerated) via the electric motor. Here, the electric motor can thus be implemented as a high-speed electric motor.

[0032] In an improved embodiment of the drive system according to the present invention, the first planetary gear set of the electric vehicle transmission is arranged axially overlapping and radially internally with respect to the electric motor. In this way, a nested structure of the drive system can be achieved, which results in an axially compact structure as a whole.

[0033] The drive system implemented according to one or more of the above-mentioned variants is in particular part of an electric vehicle drive train, which is provided here for an electric vehicle. Here, the drive system is arranged parallel to the drive axle, and the output shaft of the electric vehicle transmission is coupled to the output shaft of the drive axle. Advantageously, in this way, a compact construction of the drive axle and the drive system can be achieved, and the coupling between the output shaft of the electric vehicle transmission and the output shaft of the drive axle is in particular achieved via a differential. In addition, the drive system is arranged here in particular above the drive axle.

[0034] Within the scope of the present invention, such a vehicle drive system is provided for an electric vehicle, in particular an electric commercial vehicle. Herein, the electric vehicle can in particular be an electrically driven means of transport.

[0035] In the sense of the present invention, two structural elements of an electric vehicle transmission being "connected" or "coupled" or "in connection with each other" against relative rotation means a permanent coupling of these structural elements such that these structural elements cannot rotate independently of each other. In this regard, no shifting element is provided between these structural elements (which can be elements of a planetary gear set and / or shafts and / or anti-rotation structural elements of the transmission), but rather the corresponding structural elements are coupled to each other with a fixed speed ratio.

[0036] Conversely, if at least functionally a shifting element is provided between two structural elements, then these structural elements are non-permanently coupled to each other, but rather an anti-rotation coupling is only achieved by actuating at least the functionally intermediate shifting element. Herein, actuating the shifting element in the sense of the present invention means that the relevant shifting element is transferred into the closed state and thus brings the directly coupled structural elements into agreement in terms of their rotational movement. In the case where the relevant shifting element is designed as a form-locking shifting element, the directly anti-rotationally interconnected structural elements rotate at the same speed, while in the case of a force-locking shifting element there may still be a speed difference between the structural elements after actuating the shifting element. This intentional or unintentional state is still referred to within the scope of the present invention as the anti-rotation connection of the respective structural elements via the shifting element. Description of the Drawings

[0037] The advantageous embodiments of the present invention described below are shown in the drawings. Among them:

[0038] Figure 1 A schematic diagram of an electric vehicle according to an embodiment of the present invention is shown;

[0039] Figure 2 Shows Figure 1 A schematic diagram of the drive system of the electric vehicle; and

[0040] Figure 3 Shows Figure 2 An exemplary switching diagram of the electric vehicle transmission of the drive system. Detailed Description of the Invention

[0041] Figure 1A schematic view of an electric vehicle 1 is shown, in particular an electric commercial vehicle, such as a transport vehicle. In addition to a steerable and undriven axle 2, the electric vehicle 1 has a drive axle 3, which together with the drive system 4 is part of the vehicle drive train 5. The axle 2 is here the front axle of the electric vehicle 1. However, alternatively or in addition to the drive axle 3, the axle 2 could also be designed as a driven axle.

[0042] Now, Figure 2 shows in detail the area of the drive axle 3 of the vehicle drive train 5, where the vehicle drive train 5 is implemented here according to a design variant of the invention. It can be seen from here that the drive system 4 consists of an electric motor 6 and an electric vehicle transmission 7, which is designed according to an embodiment of the invention. The electric motor 6 is formed by a stator 8 and a rotor 9 in a manner and method that is generally known to a person skilled in the art. The electric motor 6 can operate on the one hand as a generator and on the other hand as an electric motor.

[0043] In addition to the drive shaft 10 and the output shaft 11, the electric vehicle transmission 7 also has three planetary gear sets P1, P2, and P3, which are each composed of their respective first element E11 or E12 or E13, their respective second element E21 or E22 or E23, and their respective third element E31 or E32 or E33. Here, the respective first element E11 or E12 or E13 of the respective planetary gear set P1 or P2 or P3 is respectively a sun gear, and the respective second element E21 or E22 or E23 of the respective planetary gear set P1 or P2 or P3 is respectively implemented as a planet carrier. In addition, the respective third element E31 or E32 or E33 of the respective planetary gear set P1 or P2 or P3 exists as the respective ring gear of the respective planetary gear set P1 or P2 or P3.

[0044] Here, at least one planet gear is rotatably supported on the respective planet carrier of the respective planetary gear set P1 or P2 or P3. The planet gear is not only in tooth engagement with the respective sun gear of the respective planetary gear set P1 or P2 or P3, but also in tooth engagement with the respective ring gear of the respective planetary gear set P1 or P2 or P3. In this regard, the planetary gear sets P1, P2, and P3 are currently implemented as negative planetary gear sets. However, within the scope of the invention, it is also contemplated to implement one or more of the planetary gear sets P1 to P3 as positive planetary gear sets. For this purpose, compared to the embodiment where the respective planetary gear set is a negative planetary gear set, the respective second element E21 or E22 or E23 is respectively formed by the ring gear, and the respective third element E31 or E32 or E33 is respectively formed by the planet carrier. In addition, in the case where the respective planetary gear set is implemented as a positive planetary gear set, compared to the embodiment as a negative planetary gear set, the fixed-axis transmission ratio is increased by one.

[0045] In the case of a positive planetary gear set, at least one planetary gear pair is rotatably supported in a respective planet carrier, wherein one of the planetary gears of the planetary gear pair is in tooth engagement with a respective sun gear, and the other planetary gear is in tooth engagement with a respective ring gear. In addition, the planetary gears in at least one planetary gear pair are in tooth engagement with each other.

[0046] Currently, a first element E11 of a first planetary gear set P1 is non-rotatably connected to a drive shaft 10. In addition, the drive shaft is also non-rotatably connected to a rotor 9 of an electric motor 6. In this regard, the first element E11 of the first planetary gear set P1 and the rotor 9 are also non-rotatably connected to each other via the drive shaft 10, whereby the first element E11 and the rotor 9 always rotate at the same rotational speed. Within the scope of the present invention, the first element E11 of the first planetary gear set P1 can be designed integrally with the drive shaft 10.

[0047] A second element E21 of the first planetary gear set P1 is permanently non-rotatably connected to a first element E13 of a third planetary gear set P3, such that the two elements E21 and E13 also always rotate at the same rotational speed. Similarly, a third element E31 of the first planetary gear set P1 and a first element E12 of a second planetary gear set P2 are continuously non-rotatably connected and thus permanently rotate together. The respective non-rotatable connections are realized via an intermediate shaft here.

[0048] In addition, it can be seen from Figure 2 that a second element E22 of the second planetary gear set P2 is fixed to a non-rotatable structural element 12 and is thus permanently prevented from rotational movement. Here, the non-rotatable structural element 12 is a transmission housing of an electric vehicle transmission 7, a part of the transmission housing, or a component non-rotatably connected to the transmission housing. Here, a third element E33 of the third planetary gear set P3 is also permanently fixed to the non-rotatable structural element 12, whereby the third element E33 is also continuously prevented from rotational movement. In contrast, a second element E23 of the third planetary gear set P3 is non-rotatably connected to an output shaft 11 of the electric vehicle transmission 7, whereby the second element E23 and the output shaft 11 permanently rotate together. Here, the second element E23 of the third planetary gear set P3 is also configured to be integral with the output shaft 11.

[0049] The electric vehicle transmission 7 also has three shifting elements A, B and C, which are currently formed by a common shifting device 13 and are respectively implemented as form-locking shifting elements, wherein they exist as non-synchronous claw-type shifting elements. Here, in the actuated state, the third element E32 of the second planetary gear set P2 is connected to the second element E21 of the first planetary gear set P1 and the first element E13 of the third planetary gear set P3 via the shifting element A in a rotationally fixed manner, while the shifting element B in its closed state connects the third element E32 of the second planetary gear set P2 to the output shaft 11 and thus the second element E23 of the third planetary gear set P3 in a rotationally fixed manner. The shifting element C ensures the rotationally fixed connection between the first element E12 of the second planetary gear set P2 and the third element E32 of the third planetary gear set P2 in the actuated state. In addition to the two gears explained, a third gear can also be established by another shift position. The actuator 15 operates the shift element so that the shift element is positioned between the operated shift element A and the operated shift element B, and at the same time, the sleeve slides out of the third element E32 of the second planetary gear set P2. As a result, the output shaft 11 and the second element E23 of the third planetary gear set P3 are connected to the first element of the third planetary gear set P3 and the second element E21 of the first planetary gear set P1.

[0050] At present, the shifting device 13 has a coupling element 14 in the form of a sleeve. The coupling element 14 is coupled to the third element E32 of the second planetary gear set P2 in a rotationally fixed manner and axially movable, wherein the coupling element 14 can be moved to different axial positions via the associated actuator 15. In addition to the neutral position, the coupling element 14 can also be moved to different shift positions, in which the coupling element 14 respectively reflects the actuated state of each of the shift elements A, B and C. Therefore, the actuated state of the shift element A is shown in the first shift position, the actuated state of the shift element B is shown in the second shift position, and the actuated state of the shift element C is shown in the third shift position.

[0051] In addition to the second element E23 of the third planetary gear set P3, the output shaft 11 is also permanently connected to the differential case 16 of the differential 17 in a rotationally fixed manner. The differential 17 is implemented as a bevel gear differential, which distributes the drive power introduced into the differential case 16 via the output shaft 11 to the output shafts 18 and 19 of the drive axle 3 in a manner known in principle to those skilled in the art. Here, the drive wheels 20 or 21 of the drive axle 3 are respectively connected to the output shafts 18 and 19.

[0052] In the present case, the drive system 4 is arranged parallel to the drive axle 3 and axially between the drive wheels 20 and 21. Here, the motor 6 is arranged axially adjacent to the drive wheels 21, wherein the first planetary gear set P1 of the electric vehicle transmission 7 is placed axially at the level of the stator 8 of the motor 6 and radially inside. Axially, the second planetary gear set P2 is first located after the first planetary gear set P1, then the planetary gear set P3 and the differential 17, wherein the differential can be accommodated together with the planetary gear sets P1 to P3 in the transmission housing of the electric vehicle transmission 7. The shifting device 13 is placed axially between the second planetary gear set P2 and the third planetary gear set P3.

[0053] at last, Figure 3 It also shows Figure 2 1 and 2. The exemplary switching diagram of the electric vehicle transmission device 7 shows that the functions of the first gear position G1, the second gear position G2 and the parking lock PS can be realized via the electric vehicle transmission device 7, wherein Figure 3 In the table of FIG. 1 , an X is used to indicate which of the functionally available shift elements A, B and C is actuated in order to respectively display the gear position G1 or G2 or the parking lock PS.

[0054] Thus, the first gear G1 can be obtained between the drive shaft 10 and the output shaft 11 by closing the shift element A, and the shift element B must be actuated to shift into the second gear G2 between the drive shaft 10 and the output shaft 11. In both gears G1 and G2, a force flow can be conducted between the drive shaft 10 and the output shaft 11, and thus also between the electric machine 6 and the output shafts 18 and 19 of the drive axle 3.

[0055] In contrast, the parking lock PS is realized by closing the shift element C, whereby the second planetary gear set P2 is locked due to the rotationally fixed connection between the first element E12 and the third element E32 of the second planetary gear set P2. Since the second element E22 of the second planetary gear set P2 is permanently fixed to the rotationally fixed structural element 12, the second planetary gear set P2 and thus the entire electric vehicle transmission 4 and the output shafts 18 and 19 of the drive axle 3 are also fixed. In this regard, the electric vehicle 1 can also be prevented from accidentally moving out of the parking position.

[0056] With the configuration of the electric vehicle transmission according to the invention, in addition to the display of different gear positions, a parking lock can also be realized in a compact manner.

[0057] Reference numerals list

[0058] 1 Electric Vehicles

[0059] 2 Axles

[0060] 3 Driving axle

[0061] 4 Driving system

[0062] 5 Vehicle drive train

[0063] 6 Electric motor

[0064] 7 Electric vehicle transmission

[0065] 8 Stator

[0066] 9 Rotor

[0067] 10 Drive shaft

[0068] 11 Output shaft

[0069] 12 Structural element against relative rotation

[0070] 13 Shifting device

[0071] 14 Coupling element

[0072] 15 Actuator

[0073] 16 Differential housing

[0074] 17 Differential

[0075] 18 Output shaft

[0076] 19 Output shaft

[0077] 20 Driving wheel

[0078] 21 Driving wheel

[0079] P1 First planet gear set

[0080] P2 Second planet gear set

[0081] P3 Third planet gear set

[0082] E11 First element of the first planet gear set

[0083] E21 Second element of the first planet gear set

[0084] E31 Third element of the first planet gear set

[0085] E12 First element of the second planet gear set

[0086] E22 Second element of the second planet gear set

[0087] E32 Third element of the second planet gear set

[0088] E13 First element of the third planet gear set

[0089] The second element of the E23 third planet gear set

[0090] The third element of the E33 third planet gear set

[0091] A shift element

[0092] B shift element

[0093] C shift element

[0094] G1 first gear

[0095] G2 second gear

[0096] PS parking lock

Claims

1. An electric vehicle transmission (7), comprising a drive shaft (10), an output shaft (11), and a first planetary gear set (P1), a second planetary gear set (P2), and a third planetary gear set (P3), wherein: The drive shaft (10) is configured to be coupled to an electric motor (6), wherein the first planetary gear set (P1), the second planetary gear set (P2) and the third planetary gear set (P3) respectively have respective first elements (E11, E12, E13), respective second elements (E21, E22, E23) and respective third elements (E31, E32, E33) in the form of a sun gear, a planet carrier and a ring gear, wherein at least a first shifting element (A), a second shifting element (B) and a third shifting element (C) are functionally provided, and wherein the first element (E11) of the first planetary gear set (P1) is connected to the drive shaft (10) in a rotationally fixed manner, characterized in that - the second element (E21) of the first planetary gear set (P1) and the first element (E13) of the third planetary gear set (P3) are connected to each other in a rotationally fixed manner, - the third element (E31) of the first planetary gear set (P1) and the first element (E12) of the second planetary gear set (P2) are connected to each other in a rotationally fixed manner, - the second element (E22) of the second planetary gear set (P2) is stationary, - the third element (E33) of the third planetary gear set (P3) is stationary, - the second element (E23) of the third planetary gear set (P3) is connected to the output shaft (11) in a rotationally fixed manner, - the third element (E32) of the second planetary gear set (P2) can be connected in a rotationally fixed manner to the second element (E21) of the first planetary gear set (P1) and the first element (E13) of the third planetary gear set (P3) via the first shifting element (A), and can be connected in a rotationally fixed manner to the second element (E23) of the third planetary gear set (P3) by means of the second shifting element (B), - and two of the elements (E12, E22, E32; E13, E23, E33) of the second planetary gear set (P2) or of the third planetary gear set (P3) can be connected to one another in a rotationally fixed manner via the third shifting element (C).

2. The electric vehicle transmission device (7) according to claim 1, characterized in that: When actuated, the third shifting element (C) connects the first element (E12) of the second planetary gear set (P2) and the third element (E32) of the second planetary gear set (P2) in a rotationally fixed manner, or connects the second element of the second planetary gear set and the third element of the second planetary gear set in a rotationally fixed manner.

3. The electric vehicle transmission device (7) according to claim 1 or 2, characterized in that: The shifting elements (A, B, C) are designed as form-locking shifting elements, in particular as asynchronous claw shifting elements.

4. The electric vehicle transmission device (7) according to claim 2 and claim 3, characterized in that The first shift element (A), the second shift element (B) and the third shift element (C) are formed by a common shift device (13), the coupling element (14) of which can be positioned in different shift positions, in which the coupling element (14) functionally represents the corresponding actuated state of each of the shift elements (A, B, C).

5. An electric vehicle transmission (7) according to any one of the preceding claims, characterized in that The output shaft (11) is coupled to a differential (17).

6. An electric vehicle transmission (7) according to any one of the preceding claims, characterised in that The planetary gear sets (P1, P2, P3) are arranged in the order of the first planetary gear set (P1), the second planetary gear set (P2) and the third planetary gear set (P3) on a connection portion of the drive shaft (10) for coupling the drive shaft (10) to the motor (6).

7. The electric vehicle transmission device (7) according to claim 6, characterized in that: The first shift element (A), the second shift element (B) and the third shift element (C) are axially arranged between the second planetary gear set (P2) and the third planetary gear set (P3).

8. An electric vehicle transmission (7) according to any one of the preceding claims, characterised in that A first gear position (G1) between the drive shaft (10) and the output shaft (11) is obtained by closing the first shift element (A), and a second gear position (G2) between the drive shaft (10) and the output shaft (11) is obtained by operating the second shift element (B).

9. A drive system (4) for an electric vehicle (1), comprising an electric machine (6) and an electric vehicle transmission (7) according to any one or more of claims 1 to 8, wherein: The rotor (9) of the electric motor (6) is coupled to a drive shaft (10) of the electric vehicle transmission (7).

10. The drive system (4) according to claim 9, characterized in that The first planetary gear set (P1) of the electric vehicle transmission (7) is arranged axially overlapping and radially inwardly relative to the electric machine (6).

11. A vehicle drive train (5) comprising a drive system (4) according to claim 9 or 10.

12. The vehicle drive system (5) according to claim 11, characterized in that: The drive system (4) is arranged in parallel with the drive axle (3), wherein an output shaft (11) of an electric vehicle transmission (7) is coupled to output shafts (18, 19) of the drive axle (3).

13. An electric vehicle (1), in particular an electric commercial vehicle, comprising a vehicle drive train (5) according to claim 11 or 12.

Images