Power-shift transmission for a motor vehicle transmission implemed

Abstract

The invention relates to a power-shiftable transmission (17) comprising a first spur gear stage (26), a second spur gear stage (27) and a third spur gear stage (28) and a first shifting element (B), a second shifting element (C) and a third shifting element (A). In the first spur gear stage (26), a first spur gear (31) is rotatably mounted on the first input shaft (20) and can be connected to the first input shaft (20) in a rotationally fixed manner via a first shifting element (B), the first spur gear (31) being in tooth engagement with a second spur gear (32), and the second spur gear (32) being in tooth engagement with the first input shaft (20). The second spur gear is arranged on the output shaft (18) and is coupled to a third spur gear (33) associated with the second spur gear stage (27). A fourth spur gear (34) and a fifth spur gear (35) are associated with the third spur gear stage (28), the fourth spur gear and the fifth spur gear being in tooth engagement with each other, and wherein the fourth spur gear (34) is arranged on the first input shaft (20) and the fifth spur gear (35) is arranged on the output shaft (18). By actuating the second shifting element (C), the first input shaft (20) and the output shaft (18) can be coupled to each other via the third spur gear stage (28). Furthermore, a third spur gear (33) is mounted on the second input shaft (21) in a rotationally fixed manner, and a second spur gear (32) is rotatably mounted on the output shaft (18) and can be connected to the output shaft (18) in a rotationally fixed manner via a third shifting element (A).

Description

Technical Field

[0001] The invention relates to a power-shiftable transmission for a motor vehicle transmission implemented in a grouped structure, comprising a drive shaft, a first input shaft, a second input shaft and an output shaft, wherein a first power shift element is provided, via which the first input shaft can be coupled to the drive shaft, wherein a second power shift element is provided, via which the second input shaft can be coupled to the drive shaft, wherein a first spur gear stage, a second spur gear stage and a third spur gear stage as well as a first shift element, a second shift element and a third shift element are provided, wherein in the first spur gear stage, a first spur gear is rotatably supported On a first input shaft and can be connected to the first input shaft in a rotationally fixed manner via a first shifting element, wherein the first spur gear is in tooth meshing engagement with the second spur gear, the second spur gear is arranged on the output shaft and is coupled to a third spur gear assigned to the second spur gear stage, wherein a fourth spur gear and a fifth spur gear are assigned to the third spur gear stage, the fourth spur gear and the fifth spur gear are in tooth meshing engagement with each other, wherein the fourth spur gear is arranged on the first input shaft and the fifth spur gear is arranged on the output shaft, and wherein when the second shifting element is actuated, the first input shaft and the output shaft are coupled to each other via the third spur gear stage. The invention also relates to a group transmission, a motor vehicle drive train, an agricultural or municipal utility vehicle, and a method for operating a transmission. Background Art

[0002] In the case of agricultural or municipal commercial vehicles, and in particular field tractors, the wide range of tasks often requires different driving ranges, which requires a large transmission ratio range between the slowest and the fastest gear in the motor transmission of such commercial vehicles. In addition, in the motor transmission of such commercial vehicles, small geometrical inter-stage transmission ratios must be realized between the individual gears, so that a large number of gears are available in combination with a large transmission ratio range. In order to be able to realize such a large number of gears with reasonable effort, motor transmissions for agricultural or municipal commercial vehicles are usually designed in the form of a grouped structure.

[0003] In most cases, such motor vehicle transmissions consist of a plurality of transmission groups, wherein a splitter group or main group, a secondary group preceding or following the splitter group or main group, sometimes also a secondary group, which is usually arranged downstream, and usually also a shift group and a creeper group. The gear sequence of the motor vehicle transmission is predetermined via the main group, wherein the gear sequence is influenced accordingly via the upstream and / or downstream further transmission groups, depending on the transmission ratio switched out here. In part, the secondary and main groups of such motor vehicle transmissions are designed to be power-shiftable, so that in commercial vehicle continuous operation applications, gear changes, which are mostly carried out only in the secondary and main groups, can be carried out under load and thus with high comfort.

[0004] Therefore, EP 2 916 044 A1 discloses a motor vehicle transmission implemented in a grouped structure, which is configured as a commercial vehicle for agriculture, such as a field tractor. The motor vehicle transmission is composed of a plurality of transmission groups, one of which is implemented as a transmission implemented in a dual clutch transmission type. The transmission group has two input shafts parallel to each other, each of which is assigned a power shift element. Here, each input shaft can be coupled to a common drive shaft by operating the power shift elements, which also form the driven shaft of a multi-stage transmission pre-placed in the transmission. Multiple spur gear stages are assigned to the two input shafts, which can be connected to the power flow by selectively operating the shift elements, and thus the coupling of the input shafts to the output shaft of the transmission is caused to present the transmission ratios assigned to them. The idler gears of the spur gear stages are each rotatably supported on the input shaft and can be fixed there by closing the respectively associated shifting element, while the fixed gears are mounted on the output shaft in a rotationally fixed manner. Here, a single fixed gear is simultaneously in tooth engagement with two idler gears, so that the two spur gear stages are each arranged axially in a gear plane. Summary of the invention

[0005] Based on the above-mentioned prior art, the present invention is now based on the object of providing a power-shiftable transmission which is characterized by a compact structure and low production complexity and which can simultaneously shift as many different gears as possible.

[0006] This object is achieved on the basis of the preamble of claim 1 in combination with its distinguishing features. The subsequent dependent claims each reflect advantageous developments of the invention. In addition, a motor vehicle transmission in which a transmission gear group is present in the form of a transmission according to the invention is the subject of claims 13 and 14. In addition, claim 15 relates to a motor vehicle drive train for an agricultural or municipal commercial vehicle, while claim 16 relates to an agricultural or municipal commercial vehicle. Finally, claim 17 also relates to a method for operating a power-shiftable transmission.

[0007] According to the present invention, a power-shiftable transmission comprises a drive shaft, a first input shaft, a second input shaft and an output shaft. A first power shift element is provided, via which the first input shaft can be coupled to the drive shaft, wherein a second power shift element is also provided, via which the second input shaft can be coupled to the drive shaft. In addition, a first spur gear stage, a second spur gear stage and a third spur gear stage as well as a first shifting element, a second shifting element and a third shifting element are provided, wherein in the first spur gear stage, the first spur gear is rotatably supported on the first input shaft and can be connected to the first input shaft in a rotationally fixed manner via the first shifting element. The first spur gear is in tooth meshing with the second spur gear, the second spur gear is arranged on the output shaft and is coupled to the third spur gear, the third spur gear is assigned to the second spur gear stage, the fourth spur gear and the fifth spur gear are assigned to the third spur gear stage, the fourth spur gear and the fifth spur gear are in tooth meshing with each other, the fourth spur gear is arranged on the first input shaft, and the fifth spur gear is arranged on the output shaft. When the second shifting element is actuated, the first input shaft and the output shaft are coupled to each other via the third spur gear stage.

[0008] In the meaning of the present invention, "shafts", in particular the drive shaft, the first input shaft, the second input shaft and the output shaft, should be understood as rotatable components of a power-shiftable transmission, through which the power flow can be guided between the components when the corresponding power shift elements or shifting elements are simultaneously operated. The respective shafts can connect the components of the transmission to each other axially or radially or both axially and radially. Therefore, the respective shafts can also exist as intermediate pieces, through which the respective components are connected radially, for example. In addition, the respective shafts can be implemented as one-piece components, or can exist in multiple pieces in the following manner, that is, the respective shafts are composed of multiple shaft parts connected to each other in a rotationally fixed manner. Alternatively or in addition to this, each shaft can be designed as a solid shaft, a hollow shaft, or a solid shaft in sections and a hollow shaft in sections.

[0009] In the sense of the invention, "axial" refers to the orientation in the direction of the longitudinal center axis of a power-shiftable transmission, the rotation axes of the rotatable components of the transmission, such as in particular shafts and spur gears, being arranged parallel to the longitudinal center axis. "Radial" then refers to the orientation of the respective rotatable component, in particular the respective shaft or the respective spur gear, in the diametrical direction.

[0010] In a power-shiftable transmission, the drive shaft can be coupled in a rotationally fixed manner to each input shaft via two power-shift elements. In this case, the first power-shift element couples the drive shaft to the first input shaft when actuated, while the coupling between the drive shaft and the second input shaft is established by closing the second power-shift element. A plurality of spur gear stages are arranged between the input shafts and the common output shaft, which are designed to be able to establish a coupling of the respective input shaft to the output shaft individually or in combination with one another.

[0011] In this respect, the power-shiftable transmission according to the invention consists of two sub-transmissions, each of which has an input shaft. The respective input shaft can be coupled to the output shaft by selectively actuating a shifting element to assume different gears, wherein selective actuation of the shifting element and corresponding power flow guidance via at least one spur gear stage take place in order to assume the respective gear. By additionally actuating the associated power-shifting element, the associated input shaft of the respective sub-transmission can also be coupled to the drive shaft, so that the drive shaft is ultimately coupled to the output shaft in the transmission ratio defined in the respective gear.

[0012] The power-shifting capability of the transmission is achieved in that, when the actual gear in one of the sub-transmissions is switched out and when a higher or lower target gear is about to be switched, the target gear is already preselected in the other sub-transmission in that the driven shaft is already coupled to the input shaft of the other sub-transmission by actuating the shifting element associated with the target gear. The final gear change is then achieved by switching between the power-shifting elements, which can be performed under load and thus substantially without interrupting the traction force. Accordingly, in terms of the gear sequence, the presentation of the gears is distributed alternately to the two sub-transmissions, so that during the sequential shifting of the gears of the transmission, it is always possible to change between adjacent gears under load by switching between the power-shifting elements.

[0013] In the sense of the invention, a "spur gear stage" consists of two spur gears which are permanently in tooth engagement with one another. A spur gear can also be a component of two spur gear stages at the same time in that it meshes simultaneously with two spur gears assigned to different spur gear stages. It is particularly preferred that, in a power-shiftable transmission according to the invention, exactly three spur gear stages in the form of a first spur gear stage, a second spur gear stage and a third spur gear stage are provided between the input shaft and the output shaft, but it is possible that one or more further spur gear stages can be arranged between each of the input shafts and the output shaft. Furthermore, within the scope of the invention, the spur gears which are connected to the respective shafts in a rotationally fixed manner can be present as separate spur gears which are fastened to the respective shafts in a rotationally fixed manner or as spur gears which are designed integrally with the respective shafts.

[0014] In the sense of the invention, a "power shift element" is understood to be a shift element that can be shifted under load, so that the respective power shift element, when actuated, can also bring about a rotationally fixed connection of the transmission component directly connected thereto, even under load, i.e., when transmitting torque. Thus, a first power shift element is provided for coupling the first input shaft and the drive shaft to one another when actuated, wherein this coupling can be carried out under load. A second power shift element is designed for bringing about a coupling between the second input shaft and the drive shaft when actuated, wherein this can also be carried out under load.

[0015] On the contrary, the first shift element, the second shift element and the third shift element are present as shift elements which, when actuated, respectively bring about a rotationally fixed connection between the transmission components directly connected thereto, wherein this can be done without being under load. In this respect, the first shift element, the second shift element and the third shift element can also be designed as power-shiftable shift elements, but this is not absolutely necessary for the function of the power-shiftable transmission. Therefore, the first shift element, the second shift element and the third shift element are preferably designed as non-power-shiftable elements. Preferably, in the transmission according to the invention, in addition to the two power-shift elements, there are exactly three further shift elements in the form of the first shift element, the second shift element and the third shift element. However, if, in addition to the first spur gear stage, the second spur gear stage and the third spur gear stage, one or more further spur gear stages are arranged between one of the input shafts and the output shaft, then in particular, one further shift element is assigned to each of the respective further spur gear stages.

[0016] When the first shifting element is actuated, the first spur gear is connected to the first input shaft in a rotationally fixed manner, wherein the first spur gear is rotatably supported on the first input shaft as an idler gear and is continuously meshed with the second spur gear, which is arranged on the output shaft and is therefore arranged coaxially therewith. In addition, the second spur gear is also coupled to the third spur gear, wherein within the meaning of the present invention, the coupling of the second spur gear to the third spur gear is understood to mean that the second spur gear and the third spur gear cannot rotate independently of each other, but rather that the second spur gear and the third spur gear rotate at a fixed speed ratio. The third spur gear is also assigned to the second spur gear stage.

[0017] Furthermore, the third spur gear stage consists of a fourth spur gear and a fifth spur gear stage, wherein the two spur gears are permanently meshed with one another, and the fourth spur gear is arranged on the first input shaft and is therefore arranged coaxially therewith, while the fifth spur gear is arranged on the output shaft and is therefore arranged coaxially therewith. By closing the second shifting element, the fourth spur gear and the fifth spur gear bring about a coupling of the first input shaft to the output shaft.

[0018] The invention now includes the following technical teaching, namely, the third spur gear is arranged on the second input shaft in a rotationally fixed manner, while the second spur gear is rotatably supported on the output shaft and can be connected to the output shaft in a rotationally fixed manner via a third shifting element. In other words, the third spur gear is thus permanently connected to the second input shaft in a rotationally fixed manner as a fixed gear, while the second spur gear is provided as an idler gear and is rotatably supported on the output shaft. When actuated, the third shifting element then ensures the rotationally fixed connection of the second spur gear to the output shaft, so that the second spur gear and the output shaft thus rotate together.

[0019] This design of a power-shiftable transmission has the advantage that, by arranging the third spur gear in a rotationally fixed manner on the second input shaft and implementing the second spur gear as an idler gear rotatably supported on the output shaft and rotatably supported on the first input shaft in combination with the first spur gear, a plurality of different power flow guides can be realized via these spur gears with a relatively small number of shifting elements. By actuating the third shifting element, in cooperation with the simultaneous actuation of the respective associated power shifting elements and, if necessary, the actuation of the first shifting element, a direct power flow guide from the respective input shaft to the output shaft can be realized. However, in addition, in the actuated state of the second power shifting element, and thus in the case of the power flow being guided via the second input shaft through the cooperation of the first spur gear, the second spur gear and the third spur gear, a power flow guide to the first input shaft also occurs, from which a transmission to the output shaft can be realized via the third spur gear stage. Overall, a large number of different gears can be realized with a relatively small number of spur gear stages and shifting elements, whereby the transmission according to the invention is characterized by low manufacturing complexity and a compact design.

[0020] Thus, in the transmission according to the invention, four different gears can be shifted between the drive shaft and the output shaft: In this case, the first gear is shifted between the drive shaft and the output shaft by closing the first power shift element and the first shift element and the third shift element. This results in a power flow being conducted via the drive shaft to the first input shaft, and then from the first input shaft via the first spur gear stage to the output shaft.

[0021] To shift into the second gear between the drive shaft and the output shaft, the second power shift element is then engaged and the third shift element is actuated. This results in the power flow being directed via the drive shaft to the second input shaft and from there via the second spur gear stage to the output shaft.

[0022] To obtain the third gear between the drive shaft and the output shaft, the first power shift element and the second shift element are then closed, whereby a power flow is conducted from the drive shaft to the first input shaft, wherein the power flow is then conducted further via the third spur gear stage to the output shaft.

[0023] Finally, the fourth gear is also switched between the drive shaft and the output shaft by closing the second power shift element and simultaneously closing the first shift element and the second shift element. As a result, the power flow is directed from the drive shaft to the second input shaft, wherein, in particular, the power flow is directed from the second input shaft via the second spur gear stage and the first spur gear stage to the first input shaft, which is coupled to the output shaft via the third spur gear stage. Thus, in the fourth gear, the power flow is directed from the second input shaft via the second spur gear stage, the first spur gear stage and finally via the third spur gear stage to the output shaft. Since several spur gear stages and shift elements of other gears are used here, a low manufacturing outlay and a compact design of the transmission according to the invention can be achieved.

[0024] The sequential shifting between the gears can each be performed under load, so that when the gears are shifted according to the gear sequence, all of the gears can be shifted with power. Thus, the change from the first gear to the second gear can take place under load in such a way that only a load transfer from the first power-shift element to the second power-shift element is achieved, since the third shifting element is actuated in each of the two gears. After the shift to the second gear has been achieved, the first shifting element can then be shifted into the disengaged state.

[0025] A downshift from the second gear to the first gear can also be carried out under load. To this end, in the state where the second gear is switched out and the power flow is conducted via the second input shaft, a downshift is prepared by actuating the first shift element in addition to the third shift element. Subsequently, for the downshift, a switch must be made again between only the two power shift elements by opening the second power shift element and closing the first power shift element.

[0026] In addition to downshifting from the second gear to the first gear under load, it is also possible to shift from the second gear to the third gear above it under load, for which purpose this upshift is also prepared before the actual change between the power-shift elements. In this case, in addition to the third shift element, the second shift element is also actuated, and the load transfer from the second power-shift element to the first power-shift element is then achieved by opening the second power-shift element and then closing the first power-shift element. The third shift element can then be opened.

[0027] Conversely, a downshift under load from the third gear to the second gear can be achieved by first actuating the third shift element in addition to the second shift element when shifting out of the third gear. The actual downshift is then achieved by disengaging the first power shift element and closing the second power shift element, thereby shifting out of the second gear. The second shift element can then then be disengaged.

[0028] Finally, an upshift from the third gear to the fourth gear is realized by closing the first shifting element in addition to the second shifting element in preparation for the actual upshift when the third gear is switched out, wherein the actual upshift is then performed by opening the first power-shifting element and closing the second power-shifting element. Conversely, for a downshift from the fourth gear to the third gear, only a shift is performed between the power-shifting elements and the first shifting element is then opened.

[0029] According to one embodiment of the invention, the transmission ratio between the first input shaft and the output shaft via the first spur gear stage corresponds substantially to the transmission ratio between the second input shaft and the output shaft via the second spur gear stage. Thus, the transmission ratio that is present when the power flow is conducted from the first input shaft to the output shaft only via the first spur gear stage largely corresponds to the transmission ratio that is present when the power flow is conducted from the second input shaft to the output shaft only via the second spur gear stage. This has the advantage that when the two input shafts are coupled via the first spur gear stage and the second spur gear stage, the transmission ratios of the two spur gear stages largely cancel each other out. In the fourth gear of the transmission, this results in that, when the second input shaft is coupled to the output shaft via the second spur gear stage, the first spur gear stage and the third spur gear stage, only the transmission ratio defined by the third spur gear stage is effective.

[0030] The transmission ratios achieved via the first spur gear stage correspond “substantially” to the transmission ratios achieved via the second spur gear stage, which means within the scope of the invention that there are only slight and negligible deviations between these transmission ratios. Thus, in particular, the spur gears on the input shaft side of the first spur gear stage and of the second spur gear stage differ in their number of teeth by only a few teeth, while the output shaft side is preferably provided with a constant number of teeth.

[0031] According to a design possibility of the present invention, the drive shaft is arranged axially offset with the first input shaft and the second input shaft, wherein the drive shaft is coupled to the first countershaft via the fourth spur gear stage, the first countershaft is arranged coaxially with the first input shaft and can be connected to the first input shaft in a rotationally fixed manner by actuating the first power shift element. In addition, the drive shaft is coupled to the second countershaft via the fifth spur gear stage, the second countershaft is arranged coaxially with the second input shaft and can be connected to the second input shaft in a rotationally fixed manner by actuating the second power shift element. In this case, the common drive shaft is therefore axially offset with the first input shaft and the second input shaft, wherein the drive shaft is permanently coupled to the countershafts respectively assigned to one of the input shafts and can be connected to each input shaft in a rotationally fixed manner by closing the respectively assigned power shift element. The coupling of the drive shaft to the respective countershafts is hereby permanently realized via the respectively assigned spur gear stages.

[0032] In particular, the fourth spur gear stage is formed by two spur gears, which are in tooth meshing with each other, and one of the spur gears is mounted on the drive shaft in a rotationally fixed manner, while the other spur gear is mounted on the first countershaft in a rotationally fixed manner. Similarly, the fifth spur gear stage is formed by two spur gears, which are in tooth meshing with each other, and one of the spur gears is mounted on the drive shaft in a rotationally fixed manner, while the other spur gear is mounted on the second countershaft in a rotationally fixed manner. In this way, a suitable coupling of the drive shaft to the two countershafts can be achieved. However, as an alternative to the above-mentioned embodiment in which the fourth spur gear stage and the fifth spur gear stage are formed by two associated spur gears in each case, a common spur gear of the fourth spur gear stage and the fifth spur gear stage can also be mounted on the drive shaft in a rotationally fixed manner, which spur gear simultaneously meshes with a spur gear arranged in a rotationally fixed manner on the first countershaft and is in tooth meshing with a spur gear arranged in a rotationally fixed manner on the second countershaft. In both cases, the transmission ratio defined by the fourth spur gear stage when the power flow is directed from the drive shaft to the first countershaft is different from the transmission ratio assumed by the fifth spur gear stage when the drive shaft is coupled to the second countershaft.

[0033] However, as an alternative to this, in the case of an axially offset arrangement of the drive shaft and the two input shafts, it is also conceivable to arrange the two intermediate shafts coaxially with the drive shaft, wherein each intermediate shaft can be connected to the drive shaft in a rotationally fixed manner via each associated power shift element and coupled to the respectively associated input shaft via each a spur gear stage.

[0034] An alternative embodiment of the invention is that the drive shaft is arranged coaxially with one of the input shafts and can be connected to the input shaft in a rotationally fixed manner by actuating the associated power shift element, wherein the drive shaft is coupled to an intermediate shaft via a fourth spur gear stage and a fifth spur gear stage, the intermediate shaft being arranged coaxially with the other input shaft and being connected to the other input shaft in a rotationally fixed manner by actuating the power shift element assigned to the other input shaft. In this case, the drive shaft is therefore coaxial with one of the input shafts, so that closing the associated power shift element results in a rotationally fixed connection of the drive shaft to the input shaft. Conversely, when the other power shift element is actuated, the coupling of the other input shaft to the drive shaft is produced in that the other input shaft is connected to the intermediate shaft coupled to the drive shaft via the fourth spur gear stage and the fifth spur gear stage in a rotationally fixed manner. It is particularly preferred that the drive shaft is arranged coaxially with the second input shaft and can be connected to the second input shaft in a rotationally fixed manner by closing the second power shift element, while the intermediate shaft is arranged coaxially with the first input shaft and can be connected to the first input shaft in a rotationally fixed manner by closing the first power shift element.

[0035] In a development of the above-mentioned embodiment, the spur gear of the fourth spur gear stage is arranged on the drive shaft in a rotationally fixed manner and meshes with a spur gear which is simultaneously in tooth engagement with the spur gear of the fifth spur gear stage, wherein the spur gear of the fifth spur gear stage is arranged on the countershaft in a rotationally fixed manner. Thus, the fourth spur gear stage and the fifth spur gear stage have a common spur gear which is in tooth engagement with the spur gear arranged on the drive shaft in a rotationally fixed manner on the one hand and with the spur gear arranged on the countershaft in a rotationally fixed manner on the other hand. As a result, the coupling of the drive shaft to the countershaft can be achieved via the two spur gear stages with a relatively small number of spur gears. However, as an alternative to this, the fourth spur gear stage and the fifth spur gear stage can also each have two spur gears, wherein the spur gear of the fourth spur gear stage, which is arranged on the drive shaft in a rotationally fixed manner, meshes with the spur gear of the fifth spur gear stage, which is connected in a rotationally fixed manner to the spur gear of the fifth spur gear stage, wherein the spur gear of the fifth spur gear stage is then in tooth engagement with the spur gear of the fifth spur gear stage, which is arranged on the intermediate shaft in a rotationally fixed manner.

[0036] Preferably, in the above-mentioned variant, the respective intermediate shaft is implemented at least in sections as a hollow shaft, which axially overlaps the respective associated input shaft and is arranged radially around the respective associated input shaft and can be connected to the respective associated input shaft in a rotationally fixed manner by actuating the respective associated power shift element. In particular, the respective intermediate shaft is completely present as a hollow shaft.

[0037] As an alternative to the above-mentioned improvement, the respective intermediate shaft is arranged axially beside the respective input shaft and can be connected to the respective input shaft in a rotationally fixed manner by actuating the respective power shift element. Preferably, in this variant, the respective intermediate shaft is at least located on the end side facing the respective input shaft, or exists completely as a solid shaft.

[0038] Another possible design of the invention is that the fourth spur gear is rotatably mounted on the first input shaft and can be connected to the first input shaft in a rotationally fixed manner by actuating the second shifting element, while the fifth spur gear is mounted to the output shaft in a rotationally fixed manner. In this case, in the third spur gear stage, the fourth spur gear is rotatably mounted on the first input shaft as an idler gear, while the fifth spur gear is arranged to rotate in a rotationally fixed manner as a fixed gear on the output shaft. Actuating the second shifting element then results in a rotationally fixed connection of the fourth spur gear to the first input shaft. However, within the scope of the invention, the design of the third spur gear stage can also be completely reversed in that the fourth spur gear is arranged to rotate in a rotationally fixed manner on the input shaft as a fixed gear, while the fifth spur gear is rotatably mounted on the output shaft as an idler gear and can be fixed there to the output shaft by actuating the second shifting element.

[0039] According to one embodiment of the invention, the first spur gear, the second spur gear and the third spur gear are arranged axially in one plane, wherein the second spur gear meshes with the first spur gear and the third spur gear respectively. In this case, the second spur gear is part of both the first spur gear stage and the second spur gear stage. This makes it possible to achieve an axially compact design of the power-shiftable transmission and to reduce the manufacturing effort due to the smaller number of spur gears. In principle, however, within the scope of the invention, it is also conceivable to rotatably support a further spur gear on the output shaft, which is connected to the second spur gear in a rotationally fixed manner and can be fixed to the output shaft together with the second spur gear via a third shifting element, wherein the further spur gear is then in tooth engagement with the third spur gear.

[0040] In a refinement of the present invention, the individual power shift elements are implemented as force-locking shift elements, in particular as friction shift elements for wet or dry operation. Thus, the coupling of the respective input shaft to the drive shaft can be achieved without problems under load. An implementation scheme as a multi-disk clutch is also contemplated herein.

[0041] According to a design possibility of the invention, the individual shifting elements are implemented as positive-locking shifting elements, in particular as non-synchronous claw-type shifting elements. This has the advantage that the individual shifting elements thus cause no drag losses or only small drag losses in their disengaged state, which improves the efficiency of the transmission according to the invention. As an alternative to the implementation as non-synchronous claw-type shifting elements, the individual shifting elements can also be implemented as locking synchronization devices. In addition, it is also conceivable in principle to implement one or more of the shifting elements as non-positive-locking shifting elements, and in this case in particular as diaphragm shifting elements.

[0042] The invention also relates to a motor vehicle transmission for agricultural or municipal commercial vehicles, wherein the motor vehicle transmission consists of a plurality of transmission groups and is accordingly implemented in a grouped structure. A transmission implemented in accordance with one or more of the above-described variants of the invention forms one of the transmission groups.

[0043] In particular, the transmission implemented according to one or more of the above-mentioned variants forms a main gear group of a motor vehicle transmission, wherein the coupling with another transmission gear group connected upstream is realized on the drive shaft. The other transmission gear group is particularly preferably a secondary gear group and is particularly preferably a power-shiftable secondary gear group. It is also preferred that a coupling with a differential gear group is established on the output shaft of the transmission according to the invention, via which the distribution to the drive wheels of the drive axle can be realized either as a transverse differential or as a longitudinal differential to realize the distribution to multiple drive axles. By combining the power-shiftable transmission according to the invention with the power-shiftable secondary gear group connected upstream, a power-shiftable motor vehicle transmission can be realized as necessary. However, as an alternative to this, the transmission implemented according to one or more of the above-mentioned variants can also be used as a PTO transmission of a motor vehicle transmission implemented in a grouped structure, wherein the motor vehicle transmission is especially an agricultural machinery transmission.

[0044] Furthermore, as an alternative, a transmission designed according to one or more of the above-mentioned variants can also be used in a passenger vehicle or a truck alone or in combination with another transmission as a motor vehicle transmission.

[0045] Furthermore, the subject of the invention is a motor vehicle drive train in which a motor vehicle transmission according to one or more of the above-mentioned variants is arranged. The drive side of the motor vehicle transmission, preferably the drive shaft of a transmission gear group (e.g., a secondary gear group) arranged on the drive side, is permanently coupled to an upstream drive engine, which is in particular an internal combustion engine. In particular, a torsional vibration damper is arranged between the two. However, a separation clutch can also be arranged between the upstream drive engine and the transmission gear group of the motor vehicle transmission, which is respectively arranged on the drive side, and the separation clutch can decouple the transmission gear group arranged on the drive side and thus the motor vehicle transmission from the drive engine.

[0046] As mentioned above, the motor vehicle transmission is preferably permanently coupled to at least one drive axle of the agricultural machinery via a central differential on the driven side within the motor vehicle drive train. Here, the drive axle can be permanently coupled to the driven side of the motor vehicle transmission, and the other drive axle can only be connected by operating the separating clutch.

[0047] The invention also relates to an agricultural or municipal commercial vehicle, which is particularly preferably a field tractor. Here, the commercial vehicle comprises a motor vehicle drive train according to one or more of the above-mentioned variants. Alternatively, however, the above-mentioned motor vehicle drive train can also be arranged in a working machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The advantageous embodiments of the invention explained below are shown in the accompanying drawings. In which:

[0049] Figure 1 A schematic diagram of a motor vehicle drive train for an agricultural commercial vehicle is shown;

[0050] Figure 2 Shows Figure 1 A schematic detailed view of a motor vehicle drive train, showing the region of a motor vehicle transmission;

[0051] Figure 3 The first embodiment of the present invention is shown. Figure 2 Schematic individual views of a power-shiftable transmission of a motor vehicle drive train;

[0052] Figure 4 Shows Figure 3 An exemplary shift diagram for a power-shiftable transmission;

[0053] Figures 5 to 8 Shows Figure 3 Schematic individual views of a power-shiftable transmission, showing different shifting states; and

[0054] Figures 9 to 11 A schematic individual view of a respective power-shiftable transmission according to a further embodiment of the invention is shown. DETAILED DESCRIPTION

[0055] Figure 1 A schematic illustration of a motor vehicle drive train 1 of an agricultural utility vehicle, preferably a field tractor, is shown. The motor vehicle drive train 1 comprises a drive machine 2 which is designed as an internal combustion engine and which is connected upstream of a motor vehicle transmission 3 in the motor vehicle drive train 1 .

[0056] Two drive axles 4 and 5 are also provided in the motor vehicle drive train 1, each of which has two drive wheels 6 and 7 or 8 and 9. A differential 10 is assigned to the drive axle 5, which distributes the introduced drive power as a transverse differential, if necessary while compensating for the speed difference, to the two drive wheels 8 and 9. The differential 10 is connected to the upstream motor vehicle transmission 3, wherein the differential 10 can be combined with the motor vehicle transmission 3 in a common housing.

[0057] In addition to the differential 10, the motor vehicle transmission 3 can also be connected on the output side to the differential 11 of the drive axle 4, wherein the connection can be disconnected in a particularly targeted manner. After the connection is established, the drive power directed to the differential 11 is then distributed to the two drive wheels 6 and 7, if necessary with compensation of the speed difference. Preferably, the drive axle 4 is the front axle of the agricultural machine, and the drive axle 5 is the rear axle of the agricultural machine.

[0058] Figure 2 Shows Figure 1 Schematic diagram of a portion of a motor vehicle drive train 1 in the area of ​​a drive engine 2 and a motor vehicle transmission 3. It can be seen here that the drive engine 2 is connected to a drive shaft 12 of a power-shiftable transmission group 13 of the motor vehicle transmission 3, wherein a hydraulic pump 14 is also connected to the drive shaft 12. The power-shiftable transmission group 13 is a power-shiftable auxiliary group of the motor vehicle transmission 3, wherein the transmission group 13 is also coupled at the output shaft 15 to a further transmission group 16 in the form of a transmission 17 which is also designed to be power-shiftable. The transmission 17 is connected at the output shaft 18 to a gearbox 16. Figure 1 The motor vehicle drive train 1 is connected to a downstream differential 10. Since the motor vehicle transmission 3 is constructed from the transmission groups 13 and 16, the motor vehicle transmission 3 is designed in the form of a group structure.

[0059] Figure 3 1 shows a schematic individual view of a transmission 17, wherein the transmission 17 is designed according to a first embodiment of the invention. In the transmission 17, a drive shaft 19 of the transmission 17 is arranged coaxially with an output shaft 18, wherein the drive shaft 19 also forms the output shaft 15 of the transmission group 13 connected upstream of the transmission 17 in the motor vehicle drive train 1. Therefore, a coupling to the upstream transmission group 13 is permanently established on the drive shaft 19.

[0060] The transmission 17 also has two input shafts 20 and 21, which are arranged axially offset from the output shaft 18 and the drive shaft 19 and are also arranged axially offset from each other. In addition, an intermediate shaft 22 is arranged coaxially with the input shaft 20, and an intermediate shaft 23 is arranged coaxially with the input shaft 21. The drive shaft 19, the output shaft 18 and the two input shafts 20 and 21 are basically designed as solid shafts, while the two intermediate shafts 22 and 23 are present as hollow shafts. The intermediate shaft 22 is arranged axially overlapping with the input shaft 20 and radially surrounding the input shaft, while the intermediate shaft 23 is arranged axially overlapping with the input shaft 21 and radially surrounding the input shaft.

[0061] Figure 3 1 and 2, two power shift elements 24 and 25 are provided in the transmission 17, which are each designed as a friction-locking shift element in the form of a wet-running or dry-running friction shift element. In this case, the power shift element 24 ensures a rotationally fixed connection between the input shaft 20 and the countershaft 22 in the closed state, wherein the connection via the power shift element 24 can be effected under load and with a speed difference between the input shaft 20 and the countershaft 22. When the power shift element 25 is closed, the input shaft 21 is connected to the countershaft 23 in a rotationally fixed manner, wherein this can also be effected under load and with a speed difference between the input shaft 21 and the countershaft 23.

[0062] The transmission 17 also has a plurality of spur gear stages 26, 27, 28, 29 and 30 and shifting elements A, B and C. The spur gear stage 26 is formed here by a spur gear 31 and a spur gear 32 in tooth engagement with the spur gear 31, wherein the spur gear 31 is rotatably supported on the input shaft 20 and the spur gear 32 is rotatably supported on the output shaft 18. The spur gear 32 is also part of the spur gear stage 27 in that, in addition to the spur gear 31, the spur gear 32 also meshes with a spur gear 33 and forms the spur gear stage 27 with the latter. The spur gear 33 is mounted here in a rotationally fixed manner on the input shaft 21. The spur gear stage 26 and the spur gear stage 27 are therefore arranged axially in one plane. Furthermore, spur gear 31 and spur gear 33 have essentially the same number of teeth, so that the transmission ratio defined between input shaft 20 and output shaft 18 via spur gear stage 26 largely corresponds to the transmission ratio defined between input shaft 21 and output shaft 18 via spur gear stage 27 .

[0063] Spur gear stage 28 consists of two spur gears 34 and 35 which are in toothed engagement with one another and of which spur gear 34 is rotatably supported on input shaft 20 axially adjacent to spur gear 31 , while spur gear 35 is arranged axially adjacent to spur gear 32 on output shaft 18 in a rotationally fixed manner.

[0064] Two spur gears 36 and 37 are arranged in the spur gear stage 29, which are permanently meshed with each other. Here, the spur gear 36 is mounted on the intermediate shaft 22 in a rotationally fixed manner, while the spur gear 37 is arranged on the drive shaft 19 in a rotationally fixed manner, so that the drive shaft 19 and the intermediate shaft 22 are permanently coupled to each other via the spur gear stage 29. Likewise, a permanent coupling of the drive shaft 19 to the intermediate shaft 23 is also achieved via the spur gear stage 30 in that the spur gear stage 30 is composed of two spur gears 38 and 39 that are permanently meshed with each other, wherein the spur gear 38 is arranged on the intermediate shaft 23 in a rotationally fixed manner, while the spur gear 39 is arranged on the drive shaft 19 in a rotationally fixed manner.

[0065] The shifting elements A, B and C are each designed as a positively locking individual shifting element, wherein the individual shifting elements A or B or C are present here in particular as non-synchronized tooth-type shifting elements. The shifting element A is arranged coaxially with the output shaft 18 and ensures a rotationally fixed connection of the spur gear 32 to the output shaft 18 in the closed state. The input shaft 21 is thus coupled to the output shaft 18 via the spur gear stage 27. For the transfer to the closed state, the shifting element A is assigned a coupling element 40 in the form of a sleeve, which can be moved from a neutral position to a switching position that exhibits the closed state of the shifting element A via an associated actuating actuator 41.

[0066] The shifting elements B and C are arranged coaxially with the input shaft 20, wherein the shifting element B in its closed state connects the spur gear 31 to the input shaft 20 in a rotationally fixed manner. As a result, the input shaft 20 is coupled to the input shaft 21 via the spur gear stages 26 and 27. Furthermore, if the shifting element A is also transferred to the closed state simultaneously with the shifting element B, the input shaft 20 is coupled to the output shaft 18 via the spur gear stage 26. The shifting element B is also assigned a coupling element 42 in the form of a sliding sleeve, wherein the coupling element 42 can be moved in a targeted manner from a neutral position to a switching position in which the coupling element 42 leads to the closed state of the shifting element B via an assigned adjusting actuator 43.

[0067] In its closed state, the shift element C connects the spur gear 34 to the input shaft 20 in a rotationally fixed manner, which in turn causes the input shaft 20 to be coupled to the output shaft 18 via the spur gear stage 28. The closed state of the shift element C can be caused by the associated coupling element 44, which is transferred from the neutral position to the shift position for this purpose. This movement of the coupling element 44 between the neutral position and the shift position is generated here via the adjustment actuator 45. The adjustment actuators 41, 43 and 45 of the shift elements A, B and C are especially automatically driven via the transmission controller (not shown further at present) of the transmission 17, so that the shift elements A, B and C are automatically closed. Similarly, the two power shift elements 24 and 25 are also automatically operated via the transmission controller.

[0068] The spur gear stage 30 is arranged axially adjacent to the connection of the transmission 17 via the drive shaft 19 and the transmission group 13, wherein the spur gear stage 29 follows axially first, then the spur gear stages 26 and 27 in one plane, and finally the spur gear stage 28. The two power shift elements 24 and 25 are arranged axially substantially at the same height and are axially located between the spur gear stage 29 on the one hand and the spur gear stages 26 and 27 on the other hand. Furthermore, the shifting elements A, B and C are arranged axially between the spur gear stages 26 and 27 on the one hand and the spur gear stage 28 on the other hand, wherein the shifting elements A and B are arranged axially substantially at the same height and are arranged axially adjacent to the spur gear stages 26 and 27.

[0069] By means of the transmission 17, four different transmission ratios can be provided as gears G1 to G4 between the drive shaft 19 and the output shaft 18, wherein in this case Figure 4 The shifting of these gears G1 to G4 is shown in a table in FIG. In this table, x indicates the closed state for the power shift elements 24 and 25 and the shift elements A, B and C, respectively, and o indicates the open state. Conversely, x / o means the closed or open state of the respective shift element A, B or C depending on the gear preselection. In addition, Figure 4 It can also be seen from the table that when the gears G1 to G4 are assumed, the powershift elements 24 and 25 are actuated alternately, so that the gears G1 to G4 can be shifted successively under load in the manner of a double clutch transmission.

[0070] from Figure 4It can be seen that the first gear G1 is shifted between the drive shaft 19 and the output shaft 18 by closing the power shift element 24 and the shifting elements A and B, respectively. As a result, the power flow is directed from the drive shaft 19 via the spur gear stage 29 to the intermediate shaft 22 and the input shaft 20 connected thereto in a rotationally fixed manner, and from there the further direction takes place via the spur gear stage 26 to the output shaft 18. The state of shifting the first gear G1 and the associated power flow direction are shown in FIG. Figure 5 Shown in.

[0071] On the contrary, from Figure 4 It can be seen from the table that in order to present the second gear G2, the power shift element 25 and the shift element A must be closed. This leads to Figure 6 , in which the power flow is directed from the drive shaft 19 via the spur gear stage 30 to the intermediate shaft 23, which is connected to the input shaft 21 in a rotationally fixed manner via the power shift element 25. Then, the further power flow is directed from the input shaft 21 via the spur gear stage 27 to the output shaft 18.

[0072] The third gear G3 is brought into being by closing the power shift element 24 and the shift element C, wherein the state of the third gear G3 being switched out and the associated power flow being directed to Figure 7 It can be seen here that the power flow is guided from the drive shaft 19 via the spur gear stage 29 to the intermediate shaft 22 and thus also to the input shaft 20 which is connected to the intermediate shaft in a rotationally fixed manner via the power shift element 24, wherein a further power flow is then guided from the input shaft 20 via the spur gear stage 28 to the output shaft 18.

[0073] Finally, the fourth gear G4 is also shifted between the drive shaft 19 and the output shaft 18 by closing the power shift element 25 and the shifting elements B and C, respectively. As a result, the power flow is directed from the drive shaft 19 via the spur gear stage 30 to the intermediate shaft 23 which is connected to the input shaft 21 in a rotationally fixed manner via the power shift element 25. As a special feature, in the fourth gear G4, a further power flow is then directed via the two spur gear stages 27 and 26 to the input shaft 20 and further via the spur gear stage 28 to the output shaft 18. Since the spur gears 31 and 33 have essentially the same number of teeth, the transmission ratios of the spur gear stages 26 and 27 largely cancel each other out when the rotational movement is transmitted from the input shaft 21 to the input shaft 20. This power flow is directed here Figure 8 Shown in.

[0074] The successive shifts between the gears G1 to G4 can be carried out without interrupting the traction force in the following way, namely, when the respective actual gear is currently switched out and before the actual switch to the subsequent target gear, the target gear is preselected by correspondingly operating the shifting elements involved, if necessary, and the actual gear change is then only achieved by switching between the power shifting elements.

[0075] Therefore, the shift under load from the first gear G1 to the second gear G2 occurs in that only a load transfer is performed from the power shift element 24 to the power shift element 25, since the shift element A is actuated in both gears. After the shift into the second gear G2 has been achieved, the shift element B can then be transferred to the disengaged state.

[0076] A downshift from the second gear G2 to the first gear G1 can also be carried out under load. To this end, in the state where the second gear G2 is switched out, the downshift is prepared by actuating the shift element B in addition to the shift element A, and then for the actual downshift, the power shift element 25 is switched to the power shift element 24 by opening the power shift element 25 and then closing the power shift element 24.

[0077] In addition to downshifting to the first gear G1, it is also possible to shift from the second gear G2 to the third gear G3 above it under load, for which purpose an upshift is also prepared before the actual change between the power shift elements 24 and 25. In this case, in addition to the shift element A, the shift element C is also actuated, and then the load is transferred from the power shift element 25 to the power shift element 24 by opening the power shift element 25 and then closing the power shift element 24. Subsequently, the shift element A can then be opened.

[0078] Conversely, a downshift under load from the third gear G3 to the second gear G2 can be achieved by first actuating the shift element A in addition to the shift element C when the third gear G3 is shifted out. The actual downshift is then achieved by disengaging the power shift element 24 and closing the power shift element 25, thereby shifting out the second gear G2. The shift element C can then be disengaged.

[0079] Finally, an upshift from the third gear G3 to the fourth gear G4 is also realized by closing the shift element B in addition to the shift element C in preparation for the actual upshift when the third gear G3 is switched out, wherein the actual upshift is then carried out by opening the power shift element 24 and closing the power shift element 25. In contrast, a downshift from the fourth gear G4 to the third gear G3 is realized only by switching between the power shift elements 24 and 25, and then opening the shift element B.

[0080] from Fig. 9 A schematic illustration of a power-shiftable transmission 46 can be seen, which is designed according to a second design possibility of the present invention and in which Figure 1 and Figure 2 The transmission 46 can be used in the motor vehicle transmission 3 instead of the transmission 17 as the transmission gear group 16. Figure 3 The transmission 46 corresponds to the transmission 17 of FIG. 1 , wherein the transmission 46 differs from the transmission 17 in that the intermediate shafts 47 and 48 are now designed as solid shafts. Here, the intermediate shaft 47 is coaxial with the input shaft 20 and is located at the end side of the input shaft, wherein the intermediate shaft 47 can be connected to the input shaft 20 in a rotationally fixed manner via a closed power shift element 24 and is coupled to the drive shaft 19 via a spur gear stage 29. The intermediate shaft 48 is coaxial with the input shaft 21 and is located at the end side of the input shaft and can be connected to the input shaft 21 in a rotationally fixed manner via a closed power shift element 25. In addition, the intermediate shaft 48 is permanently coupled to the drive shaft 19 by means of a spur gear stage 30. In other respects, according to Fig. 9 Implementation and basis of Figure 3 The variants of the present invention correspond to the above, so reference is made to the relevant descriptions here. Regarding the switching from the gear position G1 to G4, reference is made to Figure 4 Related description.

[0081] Fig.10 FIG. 4 shows a schematic diagram of a power-shiftable transmission 49 according to another embodiment of the present invention. The transmission 49 can also be Figure 1 and Figure 2 The transmission 3 of the motor vehicle is used in place of the transmission 17 as the transmission gear group 16 and is used together with Figure 3 The transmission 17 of the motor vehicle 1 is substantially the same. The difference here is that the connection between the transmission 49 and the drive side of the upstream transmission group 13 is established within the motor vehicle drive train 1 and the drive shaft 50 formed by the output shaft 15 of the transmission group 13 is now coaxial with the input shaft 21. Therefore, by closing the power shift element 25, the drive shaft 50 is directly connected to the input shaft 21 in a rotationally fixed manner.

[0082] The drive shaft 50 is coupled to the intermediate shaft 22 via two spur gear stages 51 and 52, wherein in the spur gear stage 51, a spur gear 53 is arranged on the drive shaft 50 in a rotationally fixed manner and is in tooth engagement with a spur gear 54 which is mounted on a shaft 55 in a rotationally fixed manner. Furthermore, the spur gear 54 is part of the spur gear stage 52 in that, in addition to the spur gear 53, it also meshes with a spur gear 56 which is arranged on the intermediate shaft 22 in a rotationally fixed manner. In other respects, according to Fig.10 Implementation and basis of Figure 3 The variants of the present invention correspond to those of the present invention, so reference is made to the description thereof. With regard to the switching from the gear position G1 to G4, reference is also made here to the description of the present invention. Figure 4 Related description.

[0083] Finally, from Fig.11 A schematic illustration of a power-shiftable transmission 57 according to a further possible embodiment of the invention is shown. This possible embodiment can also be described in detail in FIG. Figure 1 and Figure 2 The transmission 57 is used as an alternative to the transmission 17 in the motor vehicle transmission 3 of FIG. Fig.10 The variant of corresponds largely to the variant of . The only difference here is that the intermediate shaft 47 is now designed as a solid shaft and is mounted coaxially with the input shaft 20 and on its end. By closing the power shift element 24, the intermediate shaft 47 is connected to the input shaft 20 in a rotationally fixed manner. In addition, the spur gear 56 is mounted on the intermediate shaft 47 in a rotationally fixed manner. In other respects, according to Fig.11 Feasible design solutions and basis Fig.10 The variants of the present invention correspond to those of the present invention, and thus reference is made to the relevant description. Regarding the switching from the gear position G1 to G4, reference is made to Figure 4 Description of the relevant.

[0084] With the aid of the embodiments according to the invention, a power-shiftable transmission can be realized which is characterized by a compact design and low production complexity and in which a large number of different gears can be shifted.

[0085] Reference numerals list

[0086] 1Motor vehicle drive system

[0087] 2. Driving machine

[0088] 3Motor vehicle transmission

[0089] 4 drive axle

[0090] 5 drive axle

[0091] 6 drive wheels

[0092] 7 Drive wheels

[0093] 8 driven wheels

[0094] 9 driving wheels

[0095] 10 Differential

[0096] 11 Differential

[0097] 12 Drive shaft

[0098] 13 transmission gear group

[0099] 14 Hydraulic pump

[0100] 15 driven shaft

[0101] 16 transmission gear groups

[0102] 17 Transmission

[0103] 18 Output shaft

[0104] 19 Drive shaft

[0105] 20 Input shaft

[0106] 21 Input shaft

[0107] 22Intermediate shaft

[0108] 23Intermediate shaft

[0109] 24 Power shift elements

[0110] 25 Power shift elements

[0111] 26 cylindrical gear stages

[0112] 27 cylindrical gear stages

[0113] 28 cylindrical gear stages

[0114] 29 cylindrical gear stages

[0115] 30 cylindrical gear stages

[0116] 31 cylindrical gear

[0117] 32 cylindrical gear

[0118] 33 cylindrical gear

[0119] 34 cylindrical gear

[0120] 35 cylindrical gear

[0121] 36 cylindrical gear

[0122] 37 cylindrical gear

[0123] 38 cylindrical gear

[0124] 39 cylindrical gear

[0125] 40 coupling elements

[0126] 41 Adjustment actuator

[0127] 42 coupling element

[0128] 43 Adjustment actuator

[0129] 44 coupling element

[0130] 45 Adjustment actuator

[0131] 46 Transmission

[0132] 47 Intermediate shaft

[0133] 48 intermediate shaft

[0134] 49 Transmission

[0135] 50 drive shaft

[0136] 51 cylindrical gear stages

[0137] 52 cylindrical gear stages

[0138] 53 cylindrical gear

[0139] 54 cylindrical gear

[0140] 55 axis

[0141] 56 cylindrical gear

[0142] 57 Transmission

[0143] A Shifting elements

[0144] B shift element

[0145] C Shift elements

[0146] G1 first gear

[0147] G2 second gear

[0148] G3 third gear

[0149] G4 fourth gear

Claims

1. A power-shiftable transmission (17; 46; 49; 57) for a motor vehicle transmission (3) implemented in a grouped structure, the power-shiftable transmission comprising a drive shaft (19; 50), a first input shaft (20), a second input shaft (21) and an output shaft (18), wherein: A first power shift element (24) is provided, via which the first input shaft (20) can be coupled to the drive shaft (19; 50), wherein a second power shift element (25) is provided, via which the second input shaft (21) can be coupled to the drive shaft (19; 50), wherein a first spur gear stage (26), a second spur gear stage (27) and a third spur gear stage (28) as well as a first shift element (B), a second shift element (C) and a third shift element (A) are provided, wherein in the first spur gear stage (26), a first spur gear (31) is rotatably supported on the first input shaft (20) and can be connected to the first input shaft (20) in a rotationally fixed manner via the first shift element (B), wherein the first spur gear (31) is in tooth engagement with the second spur gear (32), and the second spur gear is arranged on the output shaft (18) and coupled to a third spur gear (33) assigned to the second spur gear stage (27), wherein a fourth spur gear (34) and a fifth spur gear (35) are assigned to the third spur gear stage (28), the fourth spur gear and the fifth spur gear being in tooth engagement with each other, and wherein the fourth spur gear (34) is arranged on the first input shaft (20) and the fifth spur gear (35) is arranged on the output shaft (18), and wherein, when the second shifting element (C) is actuated, the first input shaft (20) and the output shaft (18) are coupled to each other via the third spur gear stage (28), characterized in that the third spur gear (33) is mounted on the second input shaft (21) in a rotationally fixed manner, while the second spur gear (32) is rotatably supported on the output shaft (18) and can be connected to the output shaft (18) in a rotationally fixed manner via the third shifting element (A).

2. The power-shiftable transmission (17; 46; 49; 57) according to claim 1, characterized in that: The transmission ratio between the first input shaft (20) and the output shaft (18) via the first spur gear stage (26) substantially corresponds to the transmission ratio between the second input shaft (21) and the output shaft (18) via the second spur gear stage (27).

3. The power-shiftable transmission (17; 46) according to claim 1 or 2, characterized in that: The drive shaft (19) is arranged with the first input shaft (20) and the second input shaft (21) in an axially offset manner, wherein the drive shaft (19) is coupled to the first intermediate shaft (22; 47) via a fourth spur gear stage (29), the first intermediate shaft is arranged coaxially with the first input shaft (20) and can be connected to the first input shaft (20) in a rotationally fixed manner by operating the first power shift element (24), and wherein the drive shaft (19) is coupled to the second intermediate shaft (23; 48) via a fifth spur gear stage (30), the second intermediate shaft is arranged coaxially with the second input shaft (21) and can be connected to the second input shaft (21) in a rotationally fixed manner by operating the second power shift element (25).

4. The power-shiftable transmission (17; 46) according to claim 3, characterized in that The fourth spur gear stage (29) is formed by two spur gears (36, 37) which are in tooth engagement with one another and one of the spur gears is mounted on the drive shaft (19) in a rotationally fixed manner, while the other spur gear is mounted on the first intermediate shaft (22; 47) in a rotationally fixed manner, wherein the fifth spur gear stage (30) is formed by two spur gears (38, 39) which are in tooth engagement with one another and one of the spur gears is mounted on the drive shaft (19) in a rotationally fixed manner, while the other spur gear is mounted on the second intermediate shaft (23; 48) in a rotationally fixed manner.

5. The power-shiftable transmission (49; 57) according to claim 1 or 2, characterized in that: The drive shaft (50) is arranged coaxially with one of the input shafts (20, 21) and can be connected to the input shaft (21) in a rotationally fixed manner by operating an associated power shift element (25), wherein the drive shaft (50) is coupled to an intermediate shaft (22; 47) via a fourth spur gear stage (51) and a fifth spur gear stage (52), the intermediate shaft being arranged coaxially with the other input shaft (20) and being connected to the other input shaft (20) in a rotationally fixed manner by operating a power shift element (24) assigned to the other input shaft (20).

6. The power-shiftable transmission (49; 57) according to claim 5, characterized in that The spur gear (53) of the fourth spur gear stage (51) is arranged on the drive shaft (50) in a rotationally fixed manner and meshes with a spur gear (54) which is simultaneously in tooth engagement with a spur gear (56) of the fifth spur gear stage (52), wherein the spur gear (56) of the fifth spur gear stage (52) is arranged on the intermediate shaft (22; 47) in a rotationally fixed manner.

7. The power-shiftable transmission (17; 49) according to any one of claims 3 to 6, characterized in that Each intermediate shaft (22, 23; 22) is implemented as a hollow shaft at least in sections, which is arranged axially overlapping with the corresponding input shaft (20, 21; 20) and radially surrounding the corresponding input shaft, and can be connected to the corresponding input shaft (20, 21; 20) in a rotationally fixed manner by operating the corresponding power shift element (24, 25; 24).

8. The power-shiftable transmission (46; 57) according to any one of claims 3 to 7, characterized in that The intermediate shafts (47, 48; 47) are arranged axially beside the corresponding input shafts (20, 21; 20) and can be connected to the corresponding input shafts (20, 21; 20) in a rotationally fixed manner by actuating the corresponding power shift elements (24, 25; 24).

9. Power-shiftable transmission (17; 46; 49; 57) according to any of the preceding claims, characterized in that The fourth spur gear (34) is rotatably supported on the first input shaft (20) and can be connected to the first input shaft (20) in a rotationally fixed manner by actuating the second shifting element (C), while the fifth spur gear (35) is mounted in a rotationally fixed manner on the output shaft (18).

10. Power-shiftable transmission (17; 46; 49; 57) according to any of the preceding claims, characterized in that The first cylindrical gear (31), the second cylindrical gear (32) and the third cylindrical gear (33) are axially arranged in a plane, wherein the second cylindrical gear (32) is meshed with the first cylindrical gear (31) and the third cylindrical gear (33) respectively.

11. Power-shiftable transmission (17; 46; 49; 57) according to any of the preceding claims, characterized in that The individual power shift elements (24, 25) are designed as non-positive shift elements, in particular as wet-running or dry-running friction shift elements.

12. Power-shiftable transmission (17; 46; 49; 57) according to any of the preceding claims, characterized in that The individual shifting elements (A, B, C) are designed as form-locking shifting elements, in particular as asynchronous claw shifting elements.

13. A motor vehicle transmission (3) for an agricultural or municipal commercial vehicle, comprising a plurality of transmission groups (13, 16), one of the transmission groups being designed as a power-shiftable transmission (17; 46; 49; 57) according to any one or more of claims 1 to 12.

14. The motor vehicle transmission (3) according to claim 13, characterized in that A transmission group (16) embodied as a power-shiftable transmission (17; 46; 49; 57) according to any one or more of claims 1 to 12 is a main group and is coupled to a further transmission group (13), in particular a slave group, connected upstream on a drive shaft (19; 50).

15. A motor vehicle drive train (1) for an agricultural or municipal commercial vehicle, comprising a motor vehicle transmission (3) according to claim 13 or 14. 16 . An agricultural or municipal utility vehicle, in particular a field tractor, comprising a motor vehicle drive train ( 1 ) according to claim 15 .

17. Method for operating a power-shiftable transmission (17; 46; 49; 57) according to one or more of claims 1 to 12, - in, By closing the first power shift element (24) and the first shift element (B) and the third shift element (A), a first gear (G1) is switched between the drive shaft (19; 50) and the output shaft (18). - wherein a second gear (G2) is shifted between the drive shaft (19; 50) and the output shaft (18) by closing the second power shift element (25) and the third shift element (A), - wherein a third gear (G3) is shifted between the drive shaft (19; 50) and the output shaft (18) by closing the first power shift element (24) and the second shift element (C), - and wherein a fourth gear (G4) is shifted between the drive shaft (19; 50) and the output shaft (18) by closing the second power shift element (25) and the first shift element (B) and the second shift element (C).

Images