CN221023273U

CN221023273U - Motor vehicle transmission, drive unit and drive train

Info

Publication number: CN221023273U
Application number: CN202321602752.6U
Authority: CN
Inventors: 托马斯·梅尔廷; 英戈·普凡库亨; 伯纳德·胡诺尔德
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2022-06-29
Filing date: 2023-06-21
Publication date: 2024-05-28
Anticipated expiration: 2033-06-21
Also published as: DE102022206564A1

Abstract

The utility model relates to a motor vehicle transmission, a drive unit and a drive train. Which includes a drive shaft, an output shaft, a planetary gear set, a first spur gear stage and a second spur gear stage. At least functionally there are provided a first switching element, a second switching element and a third switching element. The first spur gear stage couples the drive shaft with the intermediate shaft, which is also coupled with the shafts via the second spur gear stage, respectively. The second member of the planetary gear set is connected for relative rotation with the output shaft. The first shift element serves to connect the first element of the planetary gear set and the shaft to one another in a rotationally fixed manner in the actuated state. The second shift element serves to connect the drive shaft and the first element of the planetary gear set in a rotationally fixed manner to one another in the actuated state. The third shift element is configured to fix the third element of the planetary gear set in the actuated state. The fourth shift element serves to connect the third element of the planetary gear set and the shaft in a rotationally fixed manner to one another in the actuated state.

Description

Motor vehicle transmission, drive unit and drive train

Technical Field

The utility model relates to a motor vehicle transmission for an at least partially electrically driven motor vehicle, comprising a drive shaft, an output shaft, a planetary gear set and a first and a second spur gear stage, which are designed for driving connection to a drive machine, preferably an electric motor, wherein the planetary gear set has a first element, a second element and a third element in the form of a sun gear, a planet carrier and a ring gear, and wherein at least a first, a second and a third shift element are functionally provided. The utility model further relates to a drive unit having the above-described motor vehicle transmission, to a drive train and to a method for operating a motor vehicle transmission.

Background

In hybrid and electric vehicles, a motor vehicle transmission is sometimes provided in the respective drive train between the respective motor and the drive wheels of the respective motor vehicle in order to carry out a changeover, in particular a slow changeover, of the drive movement of the motor to the drive wheels. In addition to transmissions of single gear construction, motor vehicle transmissions are used here, in particular in hybrid and electric commercial vehicles, which are capable of shifting between two or more gears.

A drive unit for an electric vehicle is known from US10,994,598B2, wherein the drive unit is composed of a motor vehicle transmission and a drive machine in the form of an electric motor. The electric machine is connected in a rotationally fixed manner to a drive shaft of the motor vehicle transmission, wherein the drive shaft can be coupled via a first spur gear stage and the first shaft to a carrier of the planetary gear set by actuating a first switching element, and the drive shaft can be coupled via a second spur gear stage and a second shaft to a sun gear of the planetary gear set by closing a second switching element. The ring gear of the planetary gear set is connected in a rotationally fixed manner to an output shaft of the motor vehicle transmission, which is coupled to a differential gear set of the motor vehicle transmission via a further spur gear stage. Furthermore, a third shift element is provided, by actuation of which the sun gear and the ring gear of the planetary gear set are connected to one another in a rotationally fixed manner, and thus an interlocking of the planetary gear set is achieved. By selectively actuating the shift element, three different gears can be represented here between the drive shaft and the output shaft.

Disclosure of utility model

Based on the above prior art, the object of the present utility model is to provide a motor vehicle transmission in which a greater number of gears can be shifted, and which is compact and efficient.

This object is achieved according to the utility model by a motor vehicle transmission for an at least partially electrically driven motor vehicle, a drive unit for an at least partially electrically driven motor vehicle and a drive train of an at least partially electrically driven motor vehicle.

According to the utility model, the motor vehicle transmission comprises a drive shaft, which is designed for driving connection with a drive machine, preferably an electric motor, an output shaft, a planetary gear set, and a first spur gear stage and a second spur gear stage. The planetary gear set has a first member, a second member and a third member in the form of a sun gear, a planet carrier and a ring gear. Furthermore, at least a first switching element, a second switching element and a third switching element are functionally provided.

In the sense of the present utility model, a "shaft", for example a drive shaft, an output shaft or another shaft of a motor vehicle transmission according to the utility model, is understood to be a rotatable component of the motor vehicle transmission via which a power flow can be conducted between the components, wherein, if necessary, an associated at least functionally provided switching element is actuated. The respective shafts can connect the components to one another in the axial or radial direction or in both the axial and radial directions by means of a corresponding course. The respective shaft can thus also be present as a short intermediate piece, via which only a connection in the radial direction or in the short axial direction is achieved.

In the sense of the present utility model, "axial" means an orientation in the direction of the longitudinal central axis of the motor vehicle transmission, to which the rotational axis of the rotatable component of the motor vehicle transmission, in particular the shaft rotational axis of the motor vehicle transmission, the rotational axis of the spur gear stage and the rotational axis of the element of the planetary gear set, are parallel. "radial" is understood to mean an orientation in the diameter direction of the respective component of the transmission.

In the motor vehicle transmission according to the utility model, the drive shaft is provided for establishing a driving connection with the drive machine. For this purpose, the drive shaft is provided in particular with a coupling point, at which a coupling of the drive shaft to the drive machine can be formed. In this case, the coupling between the drive machine and the drive shaft is such that, in the installed state of the motor vehicle transmission and with the coupling established, a constant speed ratio is always present between the rotational speed of the drive shaft of the motor vehicle transmission and the rotational speed of the drive machine. Within the scope of the utility model, at least one further transmission stage, for example a spur gear stage and/or a planetary stage, can therefore be provided between the drive shaft and the drive machine, via which transmission stage a pre-conversion of the rotational movement of the drive machine into the drive shaft can be effected. However, it is particularly preferred that a rotationally fixed connection to the drive machine is made to the drive shaft of the motor vehicle transmission according to the utility model, so that in operation the drive machine and the drive shaft will run at the same rotational speed when the connection is established.

The output shaft of the motor vehicle transmission is designed in particular for establishing a connection in the installed state of the motor vehicle transmission in the drive train with a component of the drive train that follows the motor vehicle transmission in the direction of the force flow when driven via the drive machine. The coupling of the differential gear set arranged parallel to the axis can be established here via the output shaft. In particular, the output shaft is coupled to the differential gear set via at least one spur gear stage. The arrangement according to one of the above variants is particularly suitable for use in a motor vehicle having a drive train transverse to the direction of travel of the motor vehicle. In the case of a transverse differential, the coupling of the output shaft to a shaft parallel to the axis of the output shaft is then established via a differential gear set.

However, it is particularly preferred that the output shaft is configured for output at an axial end of the motor vehicle transmission, which is opposite to the axial end at which the drive movement of the drive machine upstream of the motor vehicle transmission can be introduced into the drive shaft. The input end is thereby placed via the drive shaft and the output end via the output shaft at the mutually opposite axial ends of the transmission. The transmission of this design is suitable for use in a motor vehicle in which the drive train is oriented in the direction of travel of the motor vehicle. The input side of the subsequent differential gear set is then preferably arranged coaxially to the output shaft, wherein in the embodiment of the transverse differential, a coupling of the output shaft, in particular with an axle extending transversely to the output shaft, is established via the differential gear set. In principle, the installation position of the motor vehicle transmission according to the utility model can be realized coaxially or axially parallel to the drive machine and can be realized longitudinally or transversely in the vehicle, depending on the embodiment of the driven end of the differential.

The planetary gear set is comprised of a first member, a second member and a third member, wherein the members of the planetary gear set are formed from a sun gear, a planet carrier and a ring gear. In particular, the planetary gear set is a minus planetary gear set, wherein the planet carrier rotatably guides at least one planetary gear, wherein the at least one planetary gear is in toothed engagement with the sun gear and with the ring gear. In the case of a planetary gear set implemented as a minus planetary gear set, in particular, the first element of the planetary gear set is the sun gear, the second element of the planetary gear set is the planet carrier, and the third element of the planetary gear set is the ring gear.

Alternatively, the planetary gear set can in principle also be designed as a positive planetary gear set. In this case, at least one planetary wheel pair is then rotatably supported in the carrier of the planetary gear set, one of the planetary wheels being in mesh with the sun wheel and one of the planetary wheels being in mesh with the ring gear. Furthermore, the planet wheels of at least one planet wheel pair mesh with each other. In contrast to the embodiment as a negative planetary set, preferably the first element of the planetary gear set is the sun gear, the second element of the planetary gear set is the ring gear, and the third element of the planetary gear set is the carrier. Furthermore, the fixed ratio of the planetary gear set is increased by one compared to the embodiment as a negative planetary gear set. However, as mentioned above, the planetary gear set of the motor vehicle transmission according to the utility model is preferably embodied as a negative planetary gear set. It is furthermore preferred that exactly one planetary gear set is provided in the motor vehicle transmission according to the utility model.

The utility model now includes the technical teaching that the first spur gear stage couples the drive shaft with at least one intermediate shaft, which is also coupled with the shafts via a second spur gear stage, respectively. In addition, a second element of the planetary gear set is connected to the output shaft in a rotationally fixed manner. The first shift element is designed to connect the first element of the planetary gear set and the shaft to one another in a rotationally fixed manner in the actuated state, while the second shift element is designed to connect the drive shaft and the first element of the planetary gear set to one another in a rotationally fixed manner in the actuated state. The third shift element is furthermore designed to fix the third element of the planetary gear set in the actuated state. Furthermore, a fourth shift element is provided at least functionally, which is designed to place the third element of the planetary gear set and the shaft in a rotationally fixed connection with each other in the actuated state.

In other words, the drive shaft is thus permanently coupled via the first spur gear stage to one or more countershafts which are permanently coupled via the second spur gear stage to the shaft, or which are permanently coupled via the second spur gear stage to the shaft, respectively. In this respect, there is a fixed speed ratio between the drive shaft and the intermediate shaft, which is defined via the first spur gear stage. Likewise, the shaft and one or more intermediate shafts co-rotate at a fixed speed ratio defined by the gear ratio of the second spur gear stage. Furthermore, the second element of the planetary gear set and the output shaft are permanently connected to one another in a rotationally fixed manner and therefore always rotate at the same rotational speed.

The actuated state of at least the functionally arranged first switching element results in a rotationally fixed connection of the first element of the planetary gear set and the shaft, so that the first element of the planetary gear set and the shaft then rotate together. Conversely, if at least the functionally disposed second shift element is transferred to the closed state, a rotationally fixed connection is established between the drive shaft and the first element of the planetary gear set, whereby the drive shaft and the first element of the planetary gear set are rotated together. Manipulation of at least the functionally disposed third shift element causes the third element of the planetary gear set to be fixed, thereby preventing rotational movement of the third element of the planetary gear set. Finally, actuation of at least the functionally disposed fourth shift element results in a rotationally fixed connection between the shaft and the third element of the planetary gear set, so that the shaft and the third element of the planetary gear set rotate together.

The third element of the planetary gear set is fixed in the actuated state of at least the functionally disposed third shift element, in particular, by the fact that, when the third shift element is actuated, the third element of the planetary gear set is connected in a rotationally fixed manner to the permanently fixed, rotationally fixed structural element. The structural element which is secured against relative rotation is preferably a transmission housing of a motor vehicle transmission, a part of a transmission housing or a component which is connected to the transmission housing in a rotationally fixed manner.

The motor vehicle transmission according to the utility model therefore has at least functionally a first, a second, a third and a fourth shift element, by selective actuation of which different gears can be represented in particular between the drive shaft and the output shaft of the motor vehicle transmission. In a motor vehicle transmission according to the utility model, it is particularly preferred that exactly four shift elements are provided for their function, wherein exactly four different gears can be shifted between the drive shaft and the output shaft via these shift elements, preferably also in terms of the gear ratio. In principle, however, it is also possible within the scope of the utility model for one or more further switching elements to be provided, at least functionally, in addition to the first switching element, the second switching element, the third switching element and the fourth switching element.

The provision of a respective shift element "at least functionally" means in the sense of the utility model that at least the respective function of the respective shift element is reflected in the motor vehicle transmission according to the utility model. The switching elements may in detail be actually physically present as individual switching elements, or their function may be reflected by other components, for example switching means. The components reflecting the functions may then here combine the functions of two or more switching elements in one device.

An embodiment of the motor vehicle transmission according to the utility model has the advantage that a compactly constructed transmission can be realized by combining a planetary gear set with two spur gear stages, wherein a plurality of different gear ratios can be represented between the drive shaft and the output shaft via at least the functionally arranged shift element. By selecting the gear ratios of the spur gear stage and the planetary gear set, high conversion ratios and large ratio steps can be achieved without problems. In the case of spur gear stages and planetary gearsets, the planetary gearsets are arranged on the output side, which has the advantage that, in the case of planetary gearsets, by distributing the forces to a plurality of planet elements, in particular having the same tooth space, higher loads can be absorbed and the planetary gearsets can accordingly be subjected to higher loads. Furthermore, the motor vehicle transmission according to the utility model is characterized by good tooth efficiency. Overall, a compact motor vehicle transmission with good efficiency can be achieved, wherein in particular at least four different gear ratios can be shifted as gears.

The motor vehicle transmission according to the utility model is also suitable for use in a drive train of an at least partially electrically driven motor vehicle. It is thus possible to switch a plurality of different gears suitable for driving the motor vehicle via a drive machine designed as an electric machine via at least a functionally arranged switching element. In particular, by combining a motor vehicle transmission with a drive machine in the form of an electric motor, a drive unit suitable for use in a hybrid or electric vehicle can be provided. In this case, due to the compact design of the motor vehicle transmission according to the utility model, this is possible, so that a direct arrangement in the region of the hybrid or electric vehicle in which the drive movement is produced, for example on the respective drive axle, is also possible.

In an advantageous manner, the motor vehicle transmission according to the utility model can be operated in such a way that a first gear is shifted between the drive shaft and the output shaft by closing the first shift element and the third shift element, while a second gear is present between the drive shaft and the output shaft by closing the second shift element and the third shift element. Furthermore, by closing the first and fourth shift elements, a third gear is shifted between the drive shaft and the output shaft, whereas by closing the second and fourth shift elements, a fourth gear is obtained between the drive shaft and the output shaft.

In the first gear, a force flow guidance from the drive shaft via the two spur gear stages to the first element of the planetary gear set takes place, wherein a further shift to the output shaft takes place by means of the planetary gear set as a result of the third element of the planetary gear set being fixed. In contrast, in the second gear, the force flow is directed directly to the first element of the planetary gear set and then via the planetary gear set to the output shaft with the third element fixed. In the third gear, the force flow is guided via two spur gear stages to a shaft which is connected in a rotationally fixed manner to the output shaft via an interlocking planetary gear set. Finally, in fourth gear, the force flow is directed from the drive shaft directly to the first element of the planetary gear set, wherein the third element of the planetary gear set is coupled to the drive shaft via two spur gear stages simultaneously. In this way, a power split is achieved in the fourth gear, by means of which the ratio of the transmission ratio between the third gear and the fourth gear is reduced.

By means of the corresponding force flow guidance, a suitable representation of the gear of the motor vehicle transmission is thereby achieved. The shift between the first gear and the second gear can be achieved by switching between the two shift elements in such a way that the first shift element is opened with the third shift element closed, and then the second shift element is actuated. Conversely, in order to shift between the second gear and the third gear, two shift elements, i.e. the second shift element and the third shift element, must be opened, and then two shift elements, i.e. the first shift element and the fourth shift element, must be closed. In order to shift between the third gear and the fourth gear, it is then only necessary to perform a shift between the two shift elements again by opening the first shift element with the fourth shift element closed and subsequently actuating the second shift element.

The gear ratio acting between the drive shaft and the output shaft in the third gear is defined by the gear ratios of the two spur gear stages, while the gear ratio acting between the drive shaft and the output shaft in the second gear is defined by the fixed shaft gear ratio of the planetary gear set. In contrast, the transmission ratio between the drive shaft and the output shaft in the first gear is the product of the transmission ratios of the second gear and the third gear. Finally, in fourth gear, the transmission ratio between the drive shaft and the output shaft is formed by a power split which is influenced by the fixed ratio of the planetary gear set as well as the ratio of the two spur gear stages.

The two spur gear stages of the motor vehicle transmission according to the utility model are each preferably composed of at least two spur gears which permanently engage in tooth engagement with one another. The first spur gear stage therefore has, in particular, a first spur gear which is preferably arranged in a rotationally fixed manner on the drive shaft and which meshes with a respective spur gear arranged in a rotationally fixed manner on the at least one countershaft. If exactly one countershaft is provided in the motor vehicle transmission according to the utility model, the first spur gear of the first spur gear stage is also only in toothed engagement with the further spur gear of the first spur gear stage, which is arranged on the countershaft in a rotationally fixed manner. In contrast, if a plurality of countershafts are present in the motor vehicle transmission according to the utility model, one spur gear is preferably arranged on each countershaft in a rotationally fixed manner, wherein each individual spur gear is in toothed engagement with the first spur gear arranged on the drive shaft in a rotationally fixed manner. With several countershafts, the force flow thus flows via the first spur gear stage to the several countershafts. However, it is also conceivable for each countershaft to be coupled to the drive shaft via one associated spur gear stage in each case, wherein, however, this increases the overall axial length of the transmission as a result of the plurality of spur gear stages lying axially next to one another.

The second spur gear stage likewise has, in particular, a first spur gear which is connected to the shaft in a rotationally fixed manner and which is in toothed engagement with a spur gear which is in each case placed on at least one intermediate shaft in a rotationally fixed manner. If the motor vehicle transmission according to the utility model has exactly one countershaft, then, in addition to the first spur gear, preferably only the further spur gear is part of the second spur gear stage, wherein the first spur gear and the further spur gear are continuously in toothed engagement with one another and the further spur gear is arranged on the countershaft in a rotationally fixed manner. In the case of a plurality of countershafts, spur gears which are arranged on the shaft in a rotationally fixed manner mesh in particular simultaneously with a plurality of spur gears which are arranged in each case in a rotationally fixed manner on each of the countershafts. In this way, the force flows that were previously split via the first spur gear stage onto the several countershafts are brought together on the shafts. It is also conceivable here for each countershaft to be coupled to the shaft via each associated spur gear stage, with a plurality of countershafts, but this increases the overall axial length of the transmission, since the plurality of spur gear stages lie axially next to one another. The two spur gear stages preferably together define a gear ratio range of greater than 1.7 and less than 2.5.

In the context of the utility model, a shaft which is permanently coupled to the at least one countershaft via the second spur gear stage can be embodied as a shaft element which is constructed axially short and guides the spur gear on the output shaft side of the second spur gear stage in a rotationally fixed manner, if the connection shaft via the first switching element and via the fourth switching element is carried out axially directly in the vicinity of the spur gear on the output shaft side of the second spur gear stage. The spur gear on the output shaft side of the second spur gear stage and the shaft can be embodied in one piece, and the idler gear of the second spur gear stage can be formed in this case or can be formed in a similar manner to an idler gear.

According to an embodiment of the utility model, at least the first functionally arranged switching element and/or at least the second functionally arranged switching element and/or at least the third functionally arranged switching element and/or at least the fourth functionally arranged switching element is implemented as a form-locking switching element. In this case, the individual, at least functionally disposed shift elements are preferably configured as unsynchronized shift elements, wherein the embodiment as a claw shift element is particularly suitable here. The embodiment of the individual shift elements as form-locking shift elements has the advantage that in the open state of the respective shift element no or only low drag losses occur on the shift element. The efficiency of the motor vehicle transmission can be improved thereby. Alternatively, a single or a plurality of shift elements can also be embodied as form-locking shift elements in the form of locking synchronizers. Furthermore, as a further alternative, in which a single or a plurality of shift elements are also considered to be force-locking shift elements, these can be particularly effectively present here as diaphragm-type shift elements. In an advantageous manner, actuation of the respective switching element under load can thereby be achieved. However, it is particularly preferred that at least the first, at least the second, at least the third and at least the fourth functionally arranged switching elements are each designed as form-locking switching elements.

In an embodiment as a form-locking switching element, the first switching element and the second switching element are preferably formed by a switching device, the coupling element of which can be positioned in the first switching position and the second switching position. In the first shift position, the coupling element functionally reflects the actuated state of the first shift element and connects the first element of the planetary gear set and the shaft to one another in a rotationally fixed manner. In the second shift position, the coupling element functionally reflects the actuated state of the second shift element and places the drive shaft and the first element of the planetary gear set in a rotationally fixed connection with one another. The advantage of reflecting the function of the first and second switching elements by the switching device is that the respective coupling against relative rotation can be realized in a compact manner and in a method and with a smaller number of structural elements. In particular, the coupling element can also be positioned in a neutral position between the two shift positions, wherein no coupling of the first element of the planetary gear set takes place in the neutral position. In this regard, the neutral position may be considered as a position of the coupling element between the first and second switching positions.

Alternatively, but preferably in addition to the above variant, the third and fourth shift elements are formed by a shift device, the coupling element of which can be positioned in a first shift position and a second shift position, wherein in the first shift position the coupling element functionally reflects the actuated state of the third shift element and fixes the third element of the planetary gear set. In the second shift position, the coupling element functionally reflects the actuated state of the fourth shift element and places the third element of the planetary gear set and the shaft in a rotationally fixed connection with one another. By providing a switching device which exhibits the function of the third switching element and the fourth switching element, a compact structure can be achieved and, furthermore, the number of components of the motor vehicle transmission can be reduced, which reduces the manufacturing costs. The coupling element can in particular also be additionally positioned between the two shift positions in a neutral position, wherein in the neutral position the third element of the planetary gear set is decoupled. In this respect, the coupling element of the switching device can be positioned in three different positions, namely a first switching position, a neutral position and a second switching position.

It is particularly preferred that the two variants described above are implemented jointly, so that the functions of the first, second, third and fourth switching elements are thus reflected by the two switching devices. In this way, a shift between different gears can be performed via the two adjustment actuators.

In a development of the utility model, the drive shaft, the planetary gear set, the output shaft, the first at least functionally disposed shift element, the second at least functionally disposed shift element, the third at least functionally disposed shift element and the fourth at least functionally disposed shift element are arranged coaxially to each other. In an advantageous manner, the motor vehicle transmission according to the utility model can thus be constructed more compactly in the radial direction. Furthermore, all four at least functionally arranged switching elements are placed on the main shaft defined by the drive shaft and the output shaft and are thus easily accessible.

According to one embodiment of the utility model, the coupling point of the drive shaft, at which a drive-action connection of the drive shaft can be established, is axially followed by the first spur gear stage, then the second spur gear stage, then the planetary gear set and finally the coupling point of the output shaft. In a development of this design option, at least the functionally disposed first shift element and at least the functionally disposed second shift element are disposed axially between the first spur gear stage and the second spur gear stage. In a combination of the two variants, the first element of the planetary gear set is coupled in a rotationally fixed manner to a further shaft which extends axially from the first element of the planetary gear set through a shaft embodied as a hollow shaft and is axially opposite the drive shaft at the end face for a rotationally fixed connection via at least a functionally arranged second shift element. The further shaft is here designed in particular at least predominantly as a solid shaft, which is axially located between the drive shaft on the one hand and the planetary gear set on the other hand.

A further embodiment of the utility model provides that at least the functionally-provided third shift element and at least the functionally-provided fourth shift element are arranged axially between the second spur gear stage and the planetary gear set. The third shift element is preferably located axially between the second spur gear stage and the fourth shift element.

In one variant, the motor vehicle transmission according to the utility model is provided with exactly one intermediate shaft which is arranged parallel to the drive shaft and the shaft axis, wherein the intermediate shaft is coupled to the drive shaft via a first spur gear stage and to the shaft via a second spur gear stage. According to an alternative variant of this, the motor vehicle transmission according to the utility model has a first countershaft and a second countershaft, which are arranged axially parallel to one another and also axially parallel to the drive shaft and the shaft, wherein both the first countershaft and the second countershaft are coupled to the drive shaft via a first spur gear stage and to the shaft via a second spur gear stage, respectively.

The utility model also relates to a drive unit, which is preferably an electric axle drive unit, and which has, in addition to an electric motor, a motor vehicle transmission according to one or more of the variants described above. The rotor of the electric machine is coupled to the drive shaft of the motor vehicle transmission, wherein the coupling is provided here in particular as a rotationally fixed connection between the rotor of the electric machine and the coupling point of the drive shaft. Alternatively, however, one or more intermediate gear stages, which may be embodied in detail as spur gear stages or planetary stages, may also be provided between the drive shaft of the motor vehicle transmission and the rotor of the electric motor. Within the scope of the utility model, the electric machine can be operated in particular as a generator on the one hand and as an electric motor on the other hand.

A motor vehicle transmission or a drive unit with a motor vehicle transmission implemented according to one or more of the variants described above is in particular part of a drive train of an at least partially electrically driven motor vehicle, in particular a hybrid or electric vehicle. In this case, the drive unit can be arranged in a plane with an output shaft, which is associated with each at least one drive wheel and which is coupled to an output shaft of the motor vehicle transmission. In an advantageous manner, a compact construction of the drive axle with the drive unit is thereby possible, wherein the coupling between the output shaft of the motor vehicle transmission and the output shaft of the drive axle is achieved in particular via the intermediate differential gear set.

At least one such drive axle may be provided in a hybrid or electric vehicle, which may be, for example, an electric commercial vehicle. The hybrid or electric vehicle may be an at least partially electrically driven transport vehicle or an at least partially electrically driven bus or load vehicle from light to medium weight.

In the sense of the present utility model, two structural units of a motor vehicle transmission are "connected" or "coupled" or "in connection with each other" both mean that the structural elements are permanently coupled such that the structural units cannot rotate independently of each other. In this connection, no shift element is provided between the spur gears, which may be spur gear stages of the transmission, and/or elements of the planetary gear set and/or elements of the shaft and/or the structural elements of the anti-relative rotation, but the respective structural elements are coupled to one another with a fixed rotation ratio.

In contrast, if a switching element is provided at least functionally between two structural elements, these are not permanently coupled to one another, but only by actuating the at least functionally provided intermediate switching element. In the sense of the present utility model, actuation of the switching element means that the associated switching element is transferred into the closed state and thus the rotational movement of the structural element directly coupled to the switching element is matched. In the case of a corresponding switching element designed as a form-locking switching element, the components connected directly in a rotationally fixed manner via the switching element will run at the same rotational speed, whereas in the case of a force-locking switching element, there may be a rotational speed difference between the components even after actuation of the switching element. However, within the scope of the utility model, such a desired or undesired state is still referred to as connecting the respective structural elements in a rotationally fixed manner via the switching element.

Drawings

Advantageous embodiments of the utility model, which will be explained below, are shown in the drawings. Wherein:

FIG. 1 shows a schematic diagram of an electric vehicle;

Fig. 2 shows a schematic view of a drive unit with a motor vehicle transmission according to an embodiment of the utility model;

Fig. 3 shows a schematic view of a drive unit with a motor vehicle transmission according to a further embodiment of the utility model; and

Fig. 4 shows an exemplary shifting diagram of the motor vehicle transmission of fig. 2 and 3.

Detailed Description

Fig. 1 shows a schematic view of an electric vehicle 1, which may in particular be an electric commercial vehicle, such as a transport vehicle. In addition to the steerable, undriven vehicle axle 2, the electric vehicle 1 also has a drive axle 3 in which a drive unit 4 is provided as an electric axle drive unit. Here, the vehicle axle 2 is a front axle of the electric vehicle 1, and the drive axle 3 is a rear axle of the electric vehicle 1. Alternatively or in addition to the drive axle 3, however, the vehicle axle 2 can also be designed as a driven axle of this type.

Fig. 2 shows a schematic illustration of the drive unit 4 of fig. 1, wherein the drive unit 4 here consists of an electric motor 5 and a motor vehicle transmission 6, which is designed according to a first embodiment of the utility model. The electric machine 5 comprises a stator 7 and a rotor 8, wherein the stator 7 is permanently fixed to a structural element 9 which is secured against relative rotation. The component 9 which is secured against relative rotation is preferably a transmission housing, in which the electric machine 5 and the motor vehicle transmission 6 are preferably accommodated jointly. In particular, the structural element 9 which is secured against relative rotation can be present here as a housing part of the transmission housing or as a component which is connected to it in a rotationally fixed manner. The electric machine 5 can be operated in particular in two operating modes, namely on the one hand as a generator and on the other hand as an electric motor.

The motor vehicle transmission 6 comprises a drive shaft 10, a countershaft 11, an output shaft 12, a spur gear stage 13, a spur gear stage 14 and a planetary gear set 15. Here, the drive shaft 10, the output shaft 12 and the planetary gear set 15 are arranged coaxially to one another and also coaxially with respect to the motor 5, while the intermediate shaft 11 is offset from their axes.

The planetary gear set 15 of the motor vehicle transmission 6 is composed of a first element 16, a second element 17 and a third element 18, wherein the first element 16 is a sun gear 19, the second element 17 is present as a planet carrier 20 and the third element 18 is present as a ring gear 21. In this case, a plurality of planet gears 22 are rotatably mounted in the planet carrier 20, which in detail each engage in a toothed manner with the sun gear 19 and the ring gear 21. In this regard, the planetary gear set 15 is currently implemented as a negative planetary gear set.

The drive shaft 10 of the motor vehicle transmission 6 is connected in a rotationally fixed manner to the rotor 8 of the electric motor 5, so that the rotor 8 of the electric motor 5 and the drive shaft 10 always rotate at the same rotational speed. In this case, a rotationally fixed connection of the drive shaft 10 to the rotor 8 is established at a first coupling point 23 of the drive shaft 10. Furthermore, the drive shaft 10 is permanently coupled to the intermediate shaft 11 via the spur gear stage 13, so that there is also a permanent coupling of the rotor 8 of the electric machine 5 to the intermediate shaft 11. The spur gear stage 13 is composed of a spur gear 24 and a spur gear 25, which are continuously in toothed engagement with one another. The spur gear 24 is arranged in this case on the drive shaft 10 in a rotationally fixed manner, while the spur gear 25 is arranged on the intermediate shaft 11 in a rotationally fixed manner.

As can be seen from fig. 2, in addition to the drive shaft 10, the intermediate shaft 11 is permanently coupled to the shaft 26, wherein this coupling takes place here via the spur gear stage 14. The spur gear stage 14 consists of a spur gear 27 and a spur gear 28, which are permanently engaged with each other. In this case, spur gear 27 is arranged on intermediate shaft 11 in a rotationally fixed manner, while spur gear 28 is arranged on shaft 26 in a rotationally fixed manner. The permanent coupling of the drive shaft 10 and thus the rotor 8 of the electric machine 5 to the shaft 26 is thus achieved via the spur gear stages 13 and 14 by means of the intermediate shaft 11.

The output shaft 12 is continuously connected in a rotationally fixed manner to the carrier 20 of the planetary gear set 15, wherein the output shaft 13 also has a second coupling point 29, at which the output shaft 12 is connected to a differential gear set (not shown here) in the installed state of the drive unit 4 in the electric vehicle 1. The drive movement of the output shaft 13 is distributed via the differential gear set to the output shafts which each establish a connection with a respective one of the drive wheels of the drive axle 3. Furthermore, sun gear 19 is connected in a rotationally fixed manner to a further shaft 30, while ring gear 21 is connected in a rotationally fixed manner to shaft 31.

Functionally, the motor vehicle transmission 6 also has four shift elements A, B, C and D. The switching elements a and B are formed by the first switching means 32, while the function of the switching elements C and D is reflected by the second switching means 33.

The first switching device 32 has a first coupling element 34 in the form of a switching slide, which can be positioned in addition to the neutral position in a first switching position and in a second switching position. Such positioning is effected here via an actuator (not shown further here). In this case, the actuated state of the shift element a is represented in the first shift position, in which the shaft 26 and the further shaft 30 are connected to one another in a rotationally fixed manner via the first coupling element 34, which in turn results in the drive shaft 10 being coupled via the two spur gear stages 13 and 14 to the sun gear 19 of the planetary gear set 15. Conversely, in the second shift position, the first coupling element 34 connects the drive shaft 10 to the further shaft 30 in a rotationally fixed manner, so that the drive shaft 10 is also placed in a rotationally fixed connection with the sun gear 19 of the planetary gear set 15. Thereby exhibiting a manipulated state of the switching element B.

A second coupling element 35 in the form of a switching slide is also provided in the second switching device 33, which can be moved, in addition to the neutral position, via an actuator (not shown further in the present case) into the first switching position on the one hand and into the second switching position on the other hand. When the second coupling element 35 is positioned in the first shift position, the actuated state of the shift element C is assumed here, wherein the shaft 31 and thus the ring gear 21 are then fixed to the structural element 9, which is secured against relative rotation, via the second coupling element 35, and thus a rotational movement is prevented. Conversely, if the second coupling element is transferred from the neutral position into the second switching position, the actuated state of the switching element D is now established. The shaft 31 is connected in a rotationally fixed manner to the shaft 26 via a second coupling element 35, so that the ring gear 21 of the planetary gear set 15 is thus coupled to the drive shaft 10 via the two spur gear stages 13 and 14.

As can be seen from fig. 2, the first coupling location 23 of the drive shaft 10 is axially followed by the spur gear stage 13, then the first switching device 32, then the spur gear stage 14, then the second switching device 33, then the planetary gear set 15, and finally the second coupling location 29 of the output shaft 13. The further shaft 30, which is designed essentially as a solid shaft, is located coaxially and axially between the drive shaft 10 and the output shaft 12, which are also embodied essentially as solid shafts, respectively. Instead, the shafts 26 and 31 are each arranged as coaxially arranged hollow shafts axially overlapping the other shaft 30 and radially surrounding the same, wherein the shaft 26 can be designed to be axially short, so that the spur gear 28 and the shaft 26 are jointly assigned a form of idler or a form similar to an idler. The axially parallel intermediate shaft 11 is again essentially embodied as a solid shaft.

A schematic view of a drive unit 36 according to a further design possibility of the utility model is known from fig. 3. In this case, this design option can be applied to the electric vehicle 1 of fig. 1 instead of the drive unit 4 of fig. 2. The drive unit 36 corresponds essentially to the drive unit 4 of fig. 2, with the exception that, in addition to the intermediate shaft 11, a further intermediate shaft 38 is now provided in the motor vehicle transmission 37 of the drive unit 36, which further intermediate shaft is arranged axially parallel to the drive shaft 10, the output shaft 12, the shafts 26 and 31, the further shaft 30, the planetary gear set 15 and also axially parallel to the intermediate shaft 11. The intermediate shaft 38 is also permanently coupled to the drive shaft 10 and to the shaft 26, wherein this is accomplished in this case via spur gear stages 39 and 40, respectively. In addition to the spur gears 24 and 25, the spur gear stage 39 here comprises a spur gear 41 which is arranged on the intermediate shaft 38 in a rotationally fixed manner. The spur gear 41 is permanently engaged with the spur gear 24, which also meshes with the spur gear 25 arranged on the intermediate shaft 11 in a rotationally fixed manner and is arranged on the drive shaft 10 in a rotationally fixed manner.

As can be seen from fig. 3, in addition to spur gears 27 and 28, spur gear stage 40 has a spur gear 42, wherein spur gear 42 is arranged on countershaft 38 in a rotationally fixed manner and meshes with spur gear 28. As in the variant according to fig. 2, the spur gear 28 is arranged on the shaft 26 in a rotationally fixed manner and is also permanently in toothed engagement with the spur gear 27 arranged on the intermediate shaft 11 in a rotationally fixed manner. When the force flow is guided from the drive shaft 10 via the two countershafts 11 and 38, a division of the force flow takes place accordingly, after which the force flow merges together on the shaft 26. In other respects the variant according to fig. 3 corresponds to the variant according to fig. 2, so that reference is made to what has been described in this connection.

Fig. 4 furthermore shows an exemplary shifting diagram of the motor vehicle transmissions 6 and 37 of fig. 2 and 3. It can be seen that in the motor vehicle transmissions 6 and 37, a first gear G1, a second gear G2, a third gear G3 and a fourth gear G4 can be shifted between the drive shaft 10 and the output shaft 12, wherein in the table of fig. 4, the table is marked here with X which of the shift elements A, B, C and D formed by the first shift device 32 and the second shift device 33, respectively, shows the actuated state.

By virtue of the respective actuated state of the shift element a and the shift element C, a first gear G1 is achieved between the drive shaft 10 and the output shaft 12, as a result of which the force flow is guided from the drive shaft 10 via the two spur gear stages 13 and 14 or 39 and 40 to the shaft 26 which is connected in a rotationally fixed manner to the further shaft 30. The force flow is thus further led to the sun gear 19 of the planetary gear set 15 and is transferred to the output shaft 12 by means of the planetary gear set 15 with the ring gear 18 fixed.

In contrast, for shifting to the second gear G2, the shift element B and the shift element C are actuated, whereby the drive shaft 10 is connected in a rotationally fixed manner directly to the further shaft 30 and thus to the sun gear 19 of the planetary gear set 15. Thus, since the ring gear 18 is fixed, the driving motion of the drive shaft 10 is directly converted to the output shaft 12 via the planetary gear set 15.

Furthermore, the third gear G3 is shifted in such a manner that the operating state of the switching element a and the operating state of the switching element D are simultaneously represented. The further shaft 30 is thereby connected again in a rotationally fixed manner to the shaft 26 which is connected to the drive shaft 10 via the two spur gear stages 13 and 14 or 39 and 40. Furthermore, since the ring gear 21 of the planetary gear set 15 is connected in a rotationally fixed manner to the shaft 26 by exhibiting the actuated state of the shift element D, the ring gear 21 is finally also connected in a rotationally fixed manner to the sun gear 19 of the planetary gear set 15 by the rotationally fixed connection of the further shaft 30 to the shaft 26. This means that the planetary gear set 15 is interlocked, whereby the force flow from the drive shaft 10 is guided via the two spur gear stages 13 and 14 or 39 and 40 onto the shaft 26 and from there directly onto the output shaft 12.

Finally, the fourth gear G4 is obtained by exhibiting the actuated state of the shift elements B and D. In this case, the power split is achieved in that the force flow is directed from the drive shaft 10 on the one hand directly to the sun gear 19 of the planetary gear set 15 via a rotationally fixed connection to the further shaft 30. On the other hand, the force flow is conducted from the drive shaft 10 via the two spur gear stages 13 and 14 or 39 and 40 to the shaft 26 which is connected in a rotationally fixed manner to the ring gear 21 of the planetary gear set 15. The two partial flows of force are then led together over the planetary gear set 15 onto the carrier 20 and thus onto the output shaft 12.

By means of the embodiment according to the utility model, a compact motor vehicle transmission can be realized which has a good efficiency and which can exhibit a large number of gears.

List of reference numerals

1. Electric vehicle

2. Vehicle axle

3. Driving axle

4. Driving unit

5. Motor with a motor housing

6. Vehicle transmission device

7. Stator

8. Rotor

9. Structural element with anti-relative rotation

10. Driving shaft

11. Intermediate shaft

12. Output shaft

13. Spur gear stage

14. Spur gear stage

15. Planetary gear set

16. First element

17. Second element

18. Third element

19. Sun gear

20. Planet carrier

21. Gear ring

22. Planet wheel

23. First connection part

24. Spur gear

25. Spur gear

26. Shaft

27. Spur gear

28. Spur gear

29. Second coupling part

30. Additional shaft

31. Shaft

32. First switching device

33. Second switching device

34. First coupling element

35. Second coupling element

36. Driving unit

37. Transmission device for motor vehicle

38. Intermediate shaft

39. Spur gear stage

40. Spur gear stage

41. Spur gear

42. Spur gear

A switching element

B switching element

C switching element

D switching element

G1 First gear

G2 Second gear

G3 Third gear

G4 Fourth gear.

Claims

1. A motor vehicle transmission (6; 37) for an at least partially electrically driven motor vehicle, comprising a drive shaft (10) configured for driving connection with a drive machine, an output shaft (12), a shaft (26), a planetary gear set (15) and a first spur gear stage (13; 39) and a second spur gear stage (14; 40), wherein the planetary gear set (15) has a first element (16), a second element (17) and a third element (18) in the form of a sun gear (19), a planet carrier (20) and a ring gear (21), and wherein at least a first switching element (A), a second switching element (B) and a third switching element (C) are functionally provided,

-The first spur gear stage (13; 39) couples the drive shaft (10) with at least one intermediate shaft (11; 11, 38) which is also coupled with the shaft (26) via the second spur gear stage (14; 40), respectively,

The second element (17) of the planetary gear set (15) is connected in a rotationally fixed manner to the output shaft (12),

At least a functionally arranged first switching element (A) is designed to connect the first element (16) of the planetary gear set (15) and the shaft (26) to each other in a rotationally fixed manner in the actuated state,

At least a functionally arranged second shift element (B) is provided for placing the drive shaft (10) and the first element (16) of the planetary gear set (15) in a rotationally fixed connection with each other in the actuated state,

At least functionally, a third shift element (C) is provided for fixing the third element (18) of the planetary gear set (15) in the actuated state,

-And furthermore, at least functionally, a fourth shift element (D) is provided, which is designed to place the third element (18) of the planetary gear set (15) and the shaft (26) in a rotationally fixed connection with each other in the actuated state.

2. Motor vehicle transmission (6; 37) according to claim 1, characterized in that at least the first functionally arranged shift element (a) and/or at least the second functionally arranged shift element (B) and/or at least the third functionally arranged shift element (C) and/or at least the fourth functionally arranged shift element (D) are embodied as form-locking shift elements.

3. Motor vehicle transmission (6; 37) according to claim 2, characterized in that the first shift element (a) and the second shift element (B) are formed by a first shift device (32), the first coupling element (34) of which can be positioned in a first shift position and a second shift position, respectively, wherein in the first shift position the first coupling element (34) functionally reflects the actuated state of the first shift element (a) and connects the first element (16) of the planetary gear set (15) and the shaft (26) to each other in a rotationally fixed manner, wherein in the second shift position the first coupling element (34) functionally reflects the actuated state of the second shift element (B) and places the drive shaft (10) and the first element (16) of the planetary gear set (15) in rotationally fixed connection with each other.

4. A motor vehicle transmission (6; 37) according to claim 2 or 3, characterized in that the third shift element (C) and the fourth shift element (D) are formed by a second shift device (33), the second coupling element (35) of which can be positioned in a first shift position and a second shift position, respectively, wherein in the first shift position the second coupling element (35) functionally reflects the actuated state of the third shift element (C) and secures the third element (18) of the planetary gear set (15), wherein in the second shift position the second coupling element (35) functionally reflects the actuated state of the fourth shift element (D) and places the third element (18) of the planetary gear set (15) and the shaft (26) in a rotationally fixed connection with each other.

5. Motor vehicle transmission (6; 37) according to claim 1 or 2, characterized in that the drive shaft (10), the shaft (26), the planetary gear set (15), the output shaft (12), at least the functionally arranged first switching element (a), at least the functionally arranged second switching element (B), at least the functionally arranged third switching element (C) and at least the functionally arranged fourth switching element (D) are arranged coaxially to each other.

6. The motor vehicle transmission (6; 37) according to claim 1 or 2, characterized in that the first spur gear stage (13; 39), then the second spur gear stage (14; 40), then the planetary gear set (15), and finally the second coupling point (29) of the output shaft (12) follow, in the axial direction, a first coupling point (23) of the drive shaft (10) which can establish a drive-action connection of the drive shaft (10).

7. The motor vehicle transmission (6; 37) according to claim 6, characterized in that at least a functionally arranged first switching element (A) and at least a functionally arranged second switching element (B) are axially placed between the first spur gear stage (13; 39) and the second spur gear stage (14; 40).

8. Motor vehicle transmission (6; 37) according to claim 7, characterized in that the first element (16) of the planetary gear set (15) is connected in a rotationally fixed manner to a further shaft (30) which extends axially from the first element (16) of the planetary gear set (15) through a shaft (26) embodied as a hollow shaft and is axially opposite the drive shaft (10) at the end face for the purpose of rotationally fixed connection via at least a functionally arranged second shift element (B).

9. The motor vehicle transmission (6; 37) according to claim 6, characterized in that at least a functionally disposed third shift element (C) and at least a functionally disposed fourth shift element (D) are arranged axially between the second spur gear stage (14; 40) and the planetary gear set (15).

10. Motor vehicle transmission (6) according to claim 1 or 2, characterized in that exactly one intermediate shaft (11) is provided, which is arranged axially parallel to the drive shaft (10) and the shaft (26), wherein the intermediate shaft (11) is coupled with the drive shaft (10) via the first spur gear stage (13) and with the shaft (26) via the second spur gear stage (14).

11. Motor vehicle transmission (37) according to claim 1 or 2, characterized in that a first intermediate shaft (11) and a second intermediate shaft (38) are provided, which are arranged axially parallel to each other and also axially parallel to the drive shaft (10) and the shaft (26), wherein the first intermediate shaft (11) and the second intermediate shaft (38) are coupled with the drive shaft (10) via the first spur gear stage (39) and with the shaft (26) via the second spur gear stage (40), respectively.

12. Motor vehicle transmission (37) according to claim 1, characterized in that the drive machine is an electric motor (5).

13. Drive unit (4; 36) for an at least partially electrically driven motor vehicle, comprising an electric motor (5) and a motor vehicle transmission (6; 37) according to one or more of claims 1 to 12, wherein a rotor (8) of the electric motor (5) is coupled with a drive shaft (10) of the motor vehicle transmission (6; 37).

14. Drive unit (4; 36) according to claim 13, characterized in that the electric motor (5) is arranged coaxially with the motor vehicle transmission (6; 37), wherein the rotor (8) of the electric motor (5) is connected in a rotationally fixed manner with the drive shaft (10) of the motor vehicle transmission (6; 37).

15. Drive train of an at least partially electrically driven motor vehicle, comprising a motor vehicle transmission (6; 37) according to one or more of claims 1 to 12.

16. Drive train according to claim 15, characterized in that the drive train comprises a drive unit (4; 36) according to claim 13 or 14.