Drive device for a vehicle

Abstract

The present invention relates to a drive device (1) for a vehicle, comprising a drive (2) for mechanically operatively connecting to an engine device and an output (3) for mechanically operatively connecting to a propulsion element (7). Furthermore, the drive device (1) has a transmission assembly (4), which has a variator (36) and is formed coaxially with respect to a central shaft (13), for providing a plurality of driving ranges. The drive device (1) also comprises a reversing assembly (5) having a forward shifting element (KV) for providing the plurality of driving ranges in the forward direction and a reverse shifting element (KR) for providing the plurality of driving ranges in the reverse direction. A torque can be transmitted from the drive (2) to the output (3) via the transmission assembly (4) and the reversing assembly (5). The forward shifting element (KV) and the reverse shifting element (KR) are arranged at a distance from each other in an axially parallel manner and at a distance from the central shaft (13) of the transmission assembly (4) in an axially parallel manner.

Description

[0001] Drive device for a vehicle

[0002] Technical area

[0003] The present invention relates to a drive device for a vehicle. Furthermore, the present invention relates to a vehicle having such a drive device.

[0004] State of the art

[0005] Continuously variable power-split transmissions are used in the field of work machines and commercial vehicles. Such transmissions can have multiple gear ranges that can be shifted using a planetary roller comprising multiple shift elements. The transmissions can also have a variator by means of which the gear ratio can be continuously varied in the respective gear ranges. For example, it is known from DE 10 2006 057 836 to provide a large gear ratio over multiple stages from a transmission input to the transmission's variator, i.e., to provide a large so-called overdrive. Such transmissions also frequently have a reversing assembly for providing the gear ranges in both the forward and reverse directions. The reversing assembly can have a forward and a reverse shift element, which can be provided separately from one another, as disclosed, for example, in DE 10 2017 200240.Furthermore, DE 10 001 915 and DE 19 522 833 disclose designs in which one of the switching elements of the reversing assembly is arranged coaxially with the planetary roller, and the other switching element of the reversing assembly is arranged axially parallel to the planetary roller. A disadvantage of the gears known from the prior art is their relatively large axial length.

[0006] Description of the invention

[0007] It was therefore an object of the present invention to provide a drive device for a vehicle with multiple driving ranges, a variator and a reversing assembly, which has a particularly compact design. This object is achieved by the drive device for a vehicle according to claim 1. The drive device has a drive for mechanically operative connection to a motor device. The motor device can be one or more combustion engines and alternatively or additionally electric motors. The drive device further has an output for mechanically operative connection to a propulsion element. The propulsion element can be one or more wheels, chains or other propulsion elements of the vehicle. The output of the drive device can be mechanically operatively connected to the propulsion element via one or more differentials, for example via a transverse differential.The input and output of the drive device can be arranged axially parallel and spaced apart from each other. The vehicle can be a work machine, for example, a construction or agricultural machine such as a tractor. Furthermore, the vehicle can be a commercial vehicle, for example, a Unirnog.

[0008] In addition, the drive device comprises a transmission assembly for providing a plurality of driving ranges. Furthermore, the transmission assembly has a variator for continuously adjusting a gear ratio. The transmission assembly can, for example, provide four driving ranges. In one driving range, a fixed mechanical gear ratio can be provided between the input and output of the transmission, wherein the gear ratio can be continuously varied within the respective driving range by adjusting the variator. The variator can be a hydraulic variator, for example a variator designed as a hydrostatic device, which can have a plurality of hydraulic machines. Alternatively or additionally, it can be an electrically operated variator, which can have a plurality of electrical machines. The transmission assembly is designed coaxially to a central shaft.The transmission assembly may comprise one or more planetary gear sets and one or more shifting elements, wherein some or all of these components may be arranged coaxially with one another and coaxially with the central shaft. For example, the transmission assembly may be designed as a so-called planetary roller. Furthermore, the drive device comprises a reversing assembly with a forward shifting element for providing the multiple drive ranges of the transmission assembly in the forward direction and a reverse shifting element for providing the multiple drive ranges of the transmission assembly in the reverse direction. The reversing assembly may have any configuration as long as it can provide the claimed functionality.For example, the reversing assembly can have one or more spur gear stages and, alternatively or additionally, one or more planetary gear sets for providing the drive ranges of the transmission assembly in both the forward and reverse directions. The forward shifting element and the reverse shifting element can be frictional or positive-locking shifting elements. In one embodiment, both shifting elements are frictional shifting elements, for example, multi-plate clutches. The forward shifting element and the reverse shifting element can be provided separately and spatially separated from one another.

[0009] The drive device is designed such that a torque can be transmitted from the drive via the transmission assembly and the reversing assembly to the output. This may require the actuation of one or more shifting elements or shifting devices. Within the scope of the present invention, the forward shifting element and the reverse shifting element are provided axially parallel to one another and thus not coaxial to one another. Furthermore, within the scope of the present invention, both the forward and the reverse shifting elements are arranged axially parallel to the central shaft of the transmission assembly. Accordingly, neither the forward nor the reverse shifting element is provided coaxially to the transmission assembly, or more precisely, to the central shaft of the transmission assembly.

[0010] The drive device of the present invention can be designed with a particularly compact configuration, especially a particularly short axial length. This is made possible by the fact that neither the forward nor the reverse switching element of the reversing assembly is arranged one behind the other with the transmission assembly in the direction of the central shaft. Rather, the axially parallel arrangement of the forward and reverse switching elements to the central shaft of the transmission assembly allows a serial arrangement of the transmission assembly and the switching elements of the reversing assembly in the radial direction of the transmission assembly. Furthermore, by providing the forward and reverse switching elements separately, a design can be provided in which these can be arranged in a space-optimized manner in the circumferential direction of the transmission assembly.This makes it possible to provide a drive system that is particularly compact, both axially and radially, and thus allows for easy integration into various vehicles, such as tractors. At the same time, such a design enables high overdrive functionality, i.e., a high gear ratio from the engine to the variator.

[0011] If two elements are mechanically operatively connected, they are directly or indirectly coupled to one another in such a way that a movement of one element causes a reaction in the other element. For example, a mechanical operative connection can be provided by a positive or frictional connection. The mechanical operative connection can correspond to the meshing of corresponding toothings of the two elements. Additional elements, such as one or more spur gear stages, can be provided between the elements. A permanently rotationally fixed connection between two elements, on the other hand, is understood to be a connection in which the two elements are rigidly coupled to one another in all intended states. The elements can be present as individual components that are connected to one another in a rotationally fixed manner or as a single piece.A switching element, such as a clutch or brake, can be used to selectively establish or break a rotationally fixed connection between two elements.

[0012] In one embodiment, the drive is arranged axially parallel and spaced from the central shaft of the transmission assembly. Accordingly, within the scope of this embodiment, the transmission assembly and the drive are not provided coaxially to one another. Instead, the drive and the transmission assembly can be mechanically connected to one another via a gear stage, for example a spur gear stage, which can be designed as a single-stage. This allows the speed in the transmission assembly to be increased, which in turn leads to a reduction in the torque in the transmission assembly. The latter increases the output torque and thus the power density. One of the forward and reverse switching elements can be arranged coaxially to the drive. Alternatively or additionally, the output can also be arranged axially parallel and spaced from the central shaft of the transmission assembly. The transmission assembly can, for example, be provided between the drive and the output.One of the forward and reverse shifting elements can be arranged coaxially with the output. For example, in one embodiment, the reverse shifting element is arranged coaxially with the input, and the forward shifting element is arranged coaxially with the output. A reverse configuration, in which the forward shifting element is arranged coaxially with the input, and the reverse shifting element is arranged coaxially with the output, is also possible in an alternative embodiment. The coaxial arrangement of a shifting element of the reversing assembly and the input, and alternatively or additionally the output, allows for a drive device with particularly high compactness, especially in the radial direction of the transmission assembly.

[0013] In one embodiment, the transmission assembly, the forward shifting element, and the reverse shifting element are arranged in the direction of the central shaft of the transmission assembly such that they at least partially overlap. For example, at least one of the shifting elements of the reversing assembly is arranged such that it completely overlaps with the transmission assembly in the direction of the central shaft of the transmission assembly, i.e., does not protrude beyond the transmission assembly in the direction of the central shaft. This makes it possible to provide a drive device that is particularly compact in the axial direction. As explained above, this enables particularly good integration of the drive device into different vehicles, for example, into a tractor.In one embodiment, both the forward and reverse switching elements of the reversing assembly are arranged such that they completely overlap with the transmission assembly in the direction of the central shaft, i.e. they do not protrude beyond the transmission assembly in the direction of the central shaft.

[0014] In one embodiment, the forward switching element and the

[0015] The reverse switching element of the reversing assembly is arranged at the same height in the direction of the central shaft of the transmission assembly. For example, the two switching elements of the reversing assembly are provided at the drive-side end of the transmission assembly in the direction of the central shaft of the transmission assembly, as viewed from the drive. Providing both switching elements of the reversing assembly at the same height in the direction of the central shaft allows for a drive device with low complexity, since the proximity of the switching elements, for example, enables a simple joint connection of both to the transmission assembly. At the same time, this makes it possible to provide a drive device that has a relatively regular outer contour and can therefore be easily integrated into different vehicles.In an alternative embodiment, the forward and reverse switching elements of the reversing assembly are arranged at different heights in the direction of the central shaft.

[0016] In one embodiment, the transmission assembly has at least one planetary gear set, for example a plurality of planetary gear sets, and at least one shifting element, for example a plurality of shifting elements, for shifting a driving range. In one embodiment, the transmission assembly is designed to provide four different driving ranges with four planetary gear sets and five shifting elements. The planetary gear set and the shifting element can be designed coaxially to one another. Viewed from the drive of the drive device, the shifting element of the transmission assembly is arranged along the central shaft in front of the planetary gear set of the transmission assembly. In one embodiment, the transmission assembly has a plurality of planetary gear sets, for example three planetary gear sets, and a plurality of shifting elements, for example four shifting elements, wherein the four shifting elements are arranged in front of the three planetary gear sets in the direction of the central shaft as viewed from the drive.

[0017] The drive device can further comprise a housing, which, in one embodiment, can be designed as a supporting housing for dissipating forces from the drive device. For this purpose, the housing can have a wall thickness and mechanical strength that enables it to independently absorb and dissipate forces from the drive device that occur during normal operation. In one embodiment, this makes it possible for forces from the drive device to be dissipated via the housing. As a result, in this case, no supporting frame for absorbing forces from the drive device needs to be provided in the vehicle into which the drive device is to be integrated. Consequently, in this embodiment, a drive device can be provided that can be easily integrated into different vehicles in an autonomous manner.The housing can have one or more sections that can be detachably connected to one another.

[0018] In one embodiment, the drive device has a switching device for mechanically decoupling the reverse shifting element from the output. The switching device can be a synchronizer, for example. The switching device can ensure that no relative rotations and associated drag losses occur in the reverse shifting element when not actuated. This can be particularly advantageous if the reverse shifting element is a friction-locking switching element, for example, a multi-plate clutch.

[0019] The transmission assembly may include a first planetary gear set with a first sun gear, a first planet carrier with a planet gear rotatably mounted thereon, and a first ring gear. The transmission assembly may further include a second planetary gear set with a second sun gear, a second planet carrier with a planet gear rotatably mounted thereon, and a second ring gear. The transmission assembly may further include a third planetary gear set with a third sun gear, a third planet carrier with a planet gear rotatably mounted thereon, and a third ring gear. In addition, the transmission assembly may include a fourth planetary gear set with a fourth sun gear, a fourth planet carrier with a planet gear rotatably mounted thereon, and a fourth ring gear. One or more, for example all, of the planetary gear sets of the transmission assembly may be designed as a minus planetary gear set.With the negative planetary gear set, the planetary gears of each planetary gear set can mesh with both the sun gear and the ring gear of the planetary gear set. The various planetary gear sets can have the same outer diameter, thus providing a transmission assembly with particularly high compactness and a regular outer contour.

[0020] Furthermore, the transmission assembly can have a first shifting element, a second shifting element, a third shifting element, a fourth shifting element, and a fifth shifting element. One, several, or all of the shifting elements can be positive-locking or friction-locking shifting elements. In one embodiment, all of the shifting elements are friction-locking shifting elements. The first to fourth shifting elements can, for example, be a multi-disk clutch. The fifth shifting element can be a multi-disk brake. Other configurations are also conceivable. Furthermore, in one embodiment, the transmission assembly comprises an output shaft that is mechanically operatively connected to the reversing assembly. The output shaft can be a hollow shaft that can be arranged coaxially to the central shaft of the transmission assembly. The output shaft can be provided at the drive-side end of the transmission assembly.

[0021] The central shaft can be mechanically connected to the drive and permanently connected in a rotationally fixed manner to the second planet carrier and the first ring gear. The first sun gear can be mechanically connected to the central shaft via the variator, for example via one or more gear stages, which can be designed as spur gear stages. The variator can be connected to the gear assembly via a multi-stage spur gear stage. The first planet carrier can be permanently connected in a rotationally fixed manner to the second ring gear and the third planet carrier. Furthermore, the second sun gear can be permanently connected in a rotationally fixed manner to the third sun gear. The third ring gear can be rotationally fixedly connected to the fourth sun gear via the first switching element. Furthermore, the third sun gear can be rotationally fixedly connected to the fourth sun gear via the second switching element.The third planetary carrier can be rotationally fixedly connected to the fourth planetary carrier via the third shifting element. The fourth planetary carrier can be rotationally fixedly connected to the fourth sun gear via the fourth shifting element in order to lock the fourth planetary gear set. Furthermore, the fourth ring gear can be rotationally fixedly secured to a transmission housing via the fifth shifting element. The transmission housing can be the transmission housing described above.

[0022] In addition, the fourth planet carrier can be permanently connected to the output shaft.

[0023] With a transmission assembly designed in this way, four driving ranges can be provided on the output shaft by actuating the five different shifting elements. Via the reversing assembly, the four driving ranges can also be provided in both the forward and reverse directions on the output of the drive device. Viewed from the drive in the direction of the central shaft, the fifth shifting element can be arranged in front of the fourth planetary gear set. The fourth planetary gear set can in turn be arranged in front of the first, second, third and fourth shifting elements, which can be followed by the third, second and first planetary gear sets. With such an arrangement, a constant direction of rotation with only one tooth engagement can be achieved, for example if the transmission assembly is arranged at a distance from the drive axis and parallel to the drive.

[0024] Furthermore, the present invention relates to a vehicle with a drive device according to one of the previously described embodiments. The vehicle can be a work machine, for example, an agricultural or construction machine. In one embodiment, the work machine is a tractor or a Unirnog. Regarding the design and advantages of the individual features, reference is made to the above explanations in connection with the drive device.

[0025] Short description of the characters

[0026] Figure 1 shows a drive device for a vehicle according to an embodiment of the present invention.

[0027] Figure 2 shows a circuit diagram of the drive device from Figure 1 .

[0028] Detailed Description of Embodiments Figure 1 shows a drive device 1 for a vehicle according to an embodiment of the present invention. In the present embodiment, the vehicle is an agricultural machine in the form of a tractor. The drive device 1 has an input 2 and an output 3. Furthermore, the drive device 1 has a transmission assembly 4 for providing several driving ranges and a reversing assembly 5 for providing the driving ranges in both the forward and reverse directions. In the present embodiment, the drive 2 is mechanically operatively connected to a motor device (not shown) in the form of an internal combustion engine for driving the drive device 1. The output 3 is mechanically operatively connected via a transverse differential 6 to rear wheels 7 of the vehicle, which are designed as propulsion elements.In the present embodiment, in the mechanical operative connection between the output 3 and the rear wheels 7, in addition to the transverse differential 6, a gear stage 8 designed as a planetary gear and a brake 9 are provided for each rear wheel 7.

[0029] In addition, the drive device 1 comprises an all-wheel drive shift element 10, which in this case is designed as a multi-plate clutch. Via the all-wheel drive shift element 10, front wheels (not shown) can be mechanically operatively connected to the output 3 of the drive device 1 via a longitudinal differential (not shown). The all-wheel drive shift element 10 is arranged on the drive side of the drive device 1. The drive side is provided opposite an output side of the drive device 1. A gear pump 11 for supplying the drive device 1 with lubricating oil is mechanically operatively connected to the drive 2. Furthermore, an auxiliary unit (not shown) can be mechanically operatively connected to the drive 2 via a secondary shift element 12, which in this case is designed as a multi-plate clutch. For example, the auxiliary unit can be mechanically coupled to a power take-off shaft, which in turn can be mechanically operatively connected to the drive 2 via the secondary shift element 12.The drive 2 and the output 3 are each designed as a drive shaft 2 and an output shaft 3, respectively, and extend essentially from the drive side through the entire drive device 1 to the output side of the drive device 1. The drive 2 and the output 3 are arranged parallel but spaced apart from one another.

[0030] The gear assembly 4 is designed coaxially with a central shaft 13. The central shaft 13 of the gear assembly 4 is parallel to the input 2 and the output 3, but spaced from both. In the present embodiment, the central shaft 13 of the gear assembly 4 is arranged between the input 2 and the output 3, as can be seen from Fig. 1. In this embodiment, the central shaft 13 is mechanically operatively connected to the input 2 via a single-stage spur gear stage 14, so that a torque applied to the input 2 can be transmitted via the spur gear stage 14 to the central shaft 13 of the gear assembly 4. The gear assembly 4 also has an output shaft 15, which is arranged as a hollow shaft coaxial with the central shaft 13. The output shaft 15 can be mechanically operatively connected to the output 3 via the reversing assembly 5, as described below.

[0031] The transmission assembly 4 further comprises a first planetary gear set 16 with a first sun gear 17, a first planet carrier 18 with planetary gears 19 rotatably mounted thereon, and a first ring gear 20. The transmission assembly 4 likewise comprises a second planetary gear set 21 with a second sun gear 22, a second planet carrier 23 with planetary gears 24 rotatably mounted thereon, and a second ring gear 25. The transmission assembly 4 further comprises a third planetary gear set 26 with a third sun gear 27, a third planet carrier 28 with third planetary gears 29 rotatably mounted thereon, and a third ring gear 30. In addition, the transmission assembly 4 comprises a fourth planetary gear set 31 with a fourth sun gear 32, a fourth planet carrier 33 with fourth planetary gears 34 rotatably mounted thereon, and a fourth ring gear 35.

[0032] The transmission assembly 4 further comprises a first shifting element K1, a second shifting element K2, a third shifting element K3, a fourth shifting element K4 and a fifth shifting element BG. The first, second, third and fourth shifting elements K1, K2, K3 and K4 are each designed as a frictional shifting element, in this case as a multi-disk clutch. The fifth shifting element BG is designed as a frictional brake, in this case as a multi-disk brake. In the direction of the central shaft 13 of the transmission assembly 4, the first shifting element K1 and the second shifting element K2 are arranged at the same height. Furthermore, the third shifting element K3 and the fourth shifting element K4 are provided at the same height in the direction of the central shaft 13, but at a different height than the first shifting element K1 and the second shifting element K2.In the present embodiment, the fifth shifting element BG is arranged upstream of the fourth planetary gear set 31, viewed from the drive 2 in the direction of the central shaft 13 of the transmission assembly 4. The fourth planetary gear set 31 is in turn arranged upstream of the third and fourth shifting elements K3 and K4. The third and fourth shifting elements K3 and K4 are in turn provided upstream of the first and second shifting elements K1 and K2. Following the first and second shifting elements K1 and K2, viewed from the drive 2 in the direction of this central shaft 13, is the third planetary gear set 26, upstream of the second planetary gear set 21. The second planetary gear set 21 is in turn followed by the first planetary gear set 16.

[0033] The central shaft 13 is permanently connected in a rotationally fixed manner to the second planet carrier 23 of the second planetary gear set 21 and to the first ring gear 20 of the first planetary gear set 16. Furthermore, the first planet carrier 18 of the first planetary gear set 16 is permanently connected in a rotationally fixed manner to the second ring gear 25 of the second planetary gear set 21. The first sun gear 17 of the first planetary gear set 16 is mechanically operatively connected to the central shaft 13 via a variator 36. The variator 36 has a constant unit 37, which is operatively connected, in this case hydraulically operatively connected, to an adjusting unit 38. The constant unit 37 and the adjusting unit 38 of the variator 36 are each embodied as a hydraulic machine, and the variator 36 is embodied as a single hydraulic variator. The constant unit 37 is mechanically connected to the first sun gear 17 of the first planetary gear set 16 via a spur gear 39.The spur gear 39 is provided along the central shaft 13, viewed from the drive 2, behind the first planetary gear set 16 of the transmission assembly 4. Furthermore, the adjusting unit 38 is mechanically operatively connected to the central shaft 13 of the transmission assembly 4 via a spur gear 40. The spur gear 40 for connecting the adjusting unit 38 is arranged in front of the fifth shift element BG in the direction of the central shaft 13, viewed from the drive 2. The second sun gear 22 of the second planetary gear set 21 is permanently connected to the third sun gear 27 of the third planetary gear set 26. Furthermore, the second ring gear 25 of the second planetary gear set 21 is permanently connected to the third planet carrier 28 of the third planetary gear set 26. The fourth planet carrier 33 of the fourth planetary gear set 31 is further permanently connected to the output shaft 15.The fourth ring gear 35 of the fourth planetary gear set 31 can be rotationally fixed to a stationary component 41 by actuating the fifth shifting element BG, i.e., the multi-disk brake. In the present embodiment, the stationary component 41 is the transmission housing described below.

[0034] By actuating the first switching element K1, the third ring gear 30 of the third planetary gear set 26 can be connected in a rotationally fixed manner to the fourth sun gear 32 of the fourth planetary gear set 31. By actuating the second switching element K2, the third sun gear 27 of the third planetary gear set 26 can be connected in a rotationally fixed manner to the fourth sun gear 32 of the fourth planetary gear set 31. By actuating the third switching element K3, the third planet carrier 28 of the third planetary gear set 26 can be connected in a rotationally fixed manner to the fourth planet carrier 33 of the fourth planetary gear set 31. By actuating the fourth switching element K4, the fourth planet carrier 33 of the fourth planetary gear set 31 can be connected in a rotationally fixed manner to the fourth sun gear 32 of the fourth planetary gear set 31 in order to block the fourth planetary gear set 31.

[0035] In addition, the drive device 1 comprises the reversing assembly 5, via which the output shaft 15 of the transmission assembly 4 can be mechanically operatively connected to the output 3. The reversing assembly 5 comprises a forward shifting element KV, which in this case is arranged coaxially to the output 3. Furthermore, the reversing assembly 5 comprises a reverse shifting element KR, which in this case is arranged coaxially to the drive 2. The forward shifting element KV and the reverse shifting element KR are therefore provided at a distance parallel to one another. Furthermore, the forward shifting element KV and the reverse shifting element KR are each arranged at a distance parallel to the central shaft 13 of the transmission assembly 4. In the direction of the central shaft 13, the forward shifting element KV and the reverse shifting element KR are provided at the same height and each radially outside the fifth shifting element BG of the transmission assembly 4.Both the forward shift element KV and the reverse shift element KR are designed as frictional shift elements, in the present embodiment as a multi-plate clutch.

[0036] The forward shifting element KV and the reverse shifting element KR each have an input and an output disk pack. In the present embodiment, the input disk pack of the forward shifting element KV is mechanically connected to the output shaft 15 of the transmission assembly 4 via a single-stage spur gear stage 42. The output disk pack of the forward shifting element KV is permanently and non-rotatably connected to the output 3. By actuating the forward shifting element KV, the output shaft 15 can therefore be mechanically connected to the output 3 via the single-stage spur gear stage 42. The input disk pack of the reverse shifting element KR is mechanically connected to the output shaft 15 of the transmission assembly 4 via a spur gear stage 43. The output disk pack of the reverse shifting element KR is mechanically connected to a hollow shaft 45, which is arranged coaxially to the output 3, via a further spur gear stage 44.As previously explained, the reverse shifting element KR is arranged coaxially with the drive 2. Viewed in the direction of the central shaft 13 from the drive 2, the hollow shaft 45 is arranged behind the forward shifting element KV. Furthermore, the hollow shaft 45 is arranged in the direction of the central shaft 13 essentially at the same height as the fourth planetary gear set 31 of the transmission assembly 4. The hollow shaft 45 can be connected in a rotationally fixed manner to the output 3 via a shifting device 46, which in this case is designed as a synchronizer. Furthermore, the output 3 can be mechanically decoupled from the reverse shifting element KR via the synchronizer 46 in order to be able to mechanically decouple the reverse shifting element KR from the output 3 to reduce drag losses.

[0037] By actuating the various shift elements K1, K2, K3, K4 and BG of the transmission assembly 4, different driving ranges can be provided by the transmission assembly 4. By actuating the forward shift element KV, the different driving ranges of the transmission assembly 4 can be provided in the forward direction. By actuating the reverse shift element KR, the different driving ranges can also be provided in the reverse direction when the synchronizer 46 is closed. More precisely, the driving ranges shown in Fig. 2 can be switched by the drive device 1. Driving ranges I, II, III and IV are driving ranges for the forward direction. Driving ranges V, VI, VII and VIII are driving ranges for the reverse direction. Driving range I and driving range V have the same gear ratio. Furthermore, driving range II and driving range VI have the same gear ratio.Gear range III and gear range VII also have the same gear ratio. Gear range IV and gear range VIII also have the same gear ratio.

[0038] To select gear range I, the first shift element K1, the fifth shift element BG and the forward shift element KV are operated. To select gear range II, the second shift element K2 and the fifth shift element BG as well as the forward shift element KV are operated. To select gear range III, the second shift element K2, the third shift element K3 and the forward shift element KV are operated. To select the fourth gear range IV, the second shift element K2, the fourth shift element K4 and the forward shift element KV are operated. To select gear range V, the first shift element K1, the fifth shift element BG and the reverse shift element KR are operated. To select the sixth gear range VI, the second shift element K2, the fifth shift element BG and the reverse shift element KR are operated.To shift into the seventh gear range VII, the second shift element K2, the third shift element K3, and the reverse shift element KR are actuated. To shift into the eighth gear range VIII, the second shift element K2, the fourth shift element K4, and the reverse shift element KR are actuated. Furthermore, for all reverse gear ranges V to VIII, the synchronizer 46 is closed to establish a rotationally fixed connection between the hollow shaft 45 and the output 3. When shifting into the forward gear ranges I to IV, the synchronizer 46 is opened to release the rotationally fixed connection between the hollow shaft 45 and the output 3, whereby drag losses in the reverse gear element KR can be significantly reduced or even prevented.

[0039] In addition, the drive device 1 comprises a housing 41, only partially shown, in which the transmission assembly 4, the reversing assembly 5 and the spur gear stages 14, 39, 40, 42, 43 and 44 are accommodated. The input shaft 2 and the output shaft 3 are also accommodated in the housing, with a section of each of these protruding from the housing for connecting the components described above. The variator 36 is attached to an outer side of the housing. In this case, the housing in the present embodiment is designed as a supporting housing and is capable of absorbing and dissipating the forces occurring in the drive device 1. The vehicle, in this case the tractor, therefore does not have an additional supporting frame for accommodating the drive device 1 in the present embodiment.Instead, the drive device 1 can be integrated into the tractor via the housing without the need for mounting on a supporting frame of the tractor.

[0040] In the drive system 1, the forward CVT and reverse shift elements are arranged axially parallel to the transmission assembly 4, resulting in a particularly compact installation space. At the same time, this design enables high overdrive functionality, i.e., a particularly high gear ratio across multiple stages from the drive 2 to the variator 36. Furthermore, by arranging the transmission assembly 4 axially parallel to the drive shaft 2, a speed increase can be achieved, thereby reducing the torque in the transmission assembly 4. This, in turn, enables higher output torques and thus increased power density. Reference numerals

[0041] 1 drive device

[0042] 2 drive

[0043] 3 Downforce

[0044] 4 Gearbox assembly

[0045] 5 Reversing assembly

[0046] 6 cross differential

[0047] 7 rear wheels

[0048] 8 planetary gears

[0049] 9 Brake

[0050] 10 All-wheel drive switching element

[0051] 11 Gear pump

[0052] 12 Auxiliary switching element

[0053] 13 Central shaft

[0054] 14, 39, 40, 42, 43, 44 spur gear stage

[0055] 15 Output shaft

[0056] 16, 21 , 26, 31 planetary gear set

[0057] 17, 22, 27, 32 sun gear

[0058] 18, 23, 28, 33 planet carriers

[0059] 19, 24, 29, 34 planetary gear

[0060] 20, 25, 30, 35 ring gear

[0061] 36 Variator

[0062] 37 Constant unit

[0063] 38 adjustment unit

[0064] 41 housings

[0065] 45 hollow shaft

[0066] 46 Synchronization

[0067] K1, K2, K3, K4 switching element

[0068] BG Brake

[0069] KV forward switching element

[0070] KR reverse switching element

[0071] I, II, III, IV, V, VI, VII, VIII driving range

Claims

Patent claims 1. Drive device (1) for a vehicle with a drive (2) for mechanically operative connection to a motor device, an output (3) for mechanically operative connection to a propulsion element (7), a transmission assembly (4) having a variator (36) and formed coaxially to a central shaft (13) for providing a plurality of driving ranges and a reversing assembly (5) with a forward shift element (KV) for providing the plurality of driving ranges in the forward direction and a reverse shift element (KR) for providing the plurality of driving ranges in the reverse direction, wherein a torque can be transmitted from the drive (2) via the transmission assembly (4) and the reversing assembly (5) to the output (3), and wherein the forward shift element (KV) and the reverse shift element (KR) are arranged axially parallel to one another and spaced apart from one another and each axially parallel to the central shaft (13) of the transmission assembly (4).

2. Drive device (1) according to claim 1, characterized in that the drive (2) is arranged axially parallel to the central shaft (13) of the transmission assembly (4) and one of the forward and reverse switching elements (KV; KR) is arranged coaxially to the drive (2).

3. Drive device (1) according to claim 1 or 2, characterized in that the output (3) is arranged axially parallel to the central shaft (13) of the transmission assembly (4) and one of the forward and reverse switching elements (KV; KR) is arranged coaxially to the output (3).

4. Drive device (1) according to one of the preceding claims, characterized in that the transmission assembly (4), the forward shifting element (KV) and the reverse shifting element (KR) at least partially overlap in the direction of the central shaft (13) of the transmission assembly (4).

5. Drive device (1 ) according to one of the preceding claims, characterized in that the forward switching element (KV) and the Reverse switching element (KR) are arranged at the same height in the direction of the central shaft (13) of the transmission assembly (4).

6. Drive device (1) according to one of the preceding claims, characterized in that the transmission assembly (4) has at least one planetary gear set (16; 21; 26; 31) and at least one shifting element (K1; K2; K3; K4; BG) for shifting a driving range, wherein, viewed from the drive (2), the shifting element (K1; K2; K3; K4; BG) of the transmission assembly (4) is arranged along the central shaft (13) in front of the planetary gear set (16; 21; 26; 31) of the transmission assembly (4).

7. Drive device (1) according to one of the preceding claims, characterized in that the drive device (1) has a supporting housing (41) for dissipating forces of the drive device (1).

8. Drive device (1) according to one of the preceding claims, characterized in that the drive device (1) has a switching device (46) for mechanically decoupling the reverse switching element (KR) from the output (3) in order to reduce drag losses.

9. Drive device (1) according to one of the preceding claims, characterized in that the transmission assembly (4) comprises a first planetary gear set (16) with a first sun gear (17), a first planetary carrier (18) with a planetary gear (19) rotatably mounted thereon and a first ring gear (20), a second planetary gear set (21) with a second sun gear (22), a second planetary carrier (23) with a planetary gear (24) rotatably mounted thereon and a second ring gear (25), a third planetary gear set (26) with a third sun gear (27), a third planetary carrier (28) with a planetary gear (29) rotatably mounted thereon and a third ring gear (30), a fourth planetary gear set (31) with a fourth sun gear (32), a fourth planetary carrier (33) with a planetary gear (34) rotatably mounted thereon and a fourth ring gear (35), a first shifting element (K1), a second shifting element (K2), a third shifting element (K3), a fourth switching element (K4),a fifth switching element (BG) and a reversing assembly (5), mechanically operatively connected output shaft (15), wherein the central shaft (13) is mechanically operatively connected to the drive (2) and is permanently connected to the second planet carrier (23) and the first ring gear (20), the first sun gear (17) is mechanically operatively connected to the central shaft (13) via the variator (36), the first planet carrier (18) is permanently connected to the second ring gear (25) and the third planet carrier (28), the second sun gear (22) is permanently connected to the third sun gear (27), the third ring gear (30) is rotatably connectable to the fourth sun gear (32) via the first switching element (K1), the third sun gear (27) is rotatably connectable to the fourth sun gear (32) via the second switching element (K2), the third planet carrier (28) is rotatably connectable to the fourth planet carrier (33) via the third switching element (K3) can be connected,the fourth planet carrier (33) is rotatably connectable to the fourth sun gear (32) via the fourth switching element (K4), the fourth ring gear (35) is rotatably fixable to a transmission housing (41) via the fifth switching element (BG), and the fourth planet carrier (33) is permanently rotatably connected to the output shaft (15).

10. Vehicle with a drive device (1) according to one of the preceding claims.

Images