Reversing gearbox with double clutch

Abstract

The present invention relates to a reversing gear (2) for a drive train (16), comprising at least one double clutch (1), a transmission gear (17) and at least one output shaft connection (6), wherein the double clutch (1) is configured for the releasable transmission of a torque about a rotational axis (3), comprising at least the following components: - a motor shaft connection (4); - a first output shaft (5) which can be connected to at least one output shaft connection (6) in a torque-transmitting manner and in a first direction of rotation (7); - a second output shaft (8) which can be connected to the aforementioned output shaft connection (6) in a torque-transmitting manner and in a second direction of rotation (9) opposite to the first direction of rotation (7); - a first partial coupling (10) by means of which a torque can be detachably transmitted between the motor shaft connection (4) and the first output shaft (5); and - a second partial coupling (11) by means of which a torque can be detachably transmitted between the motor shaft connection (4) and the second output shaft (8), wherein the motor shaft connection (4) can be connected to the output shaft connection (6) in a torque-transmitting manner in a reversible direction of rotation (7,9) by means of the transmission gear (17) and by means of the partial couplings (10,11) without interruption of load, wherein a disconnect coupling (12) is arranged on the first output shaft (5) for the immediate disconnection of a torque transmission between the first output shaft (5) and the second output shaft (8).

Description

[0001] The invention relates to a reversing gear with a double clutch, wherein the double clutch is designed to releasably transmit a torque about a rotational axis, comprising at least the following components: - a motor shaft connection; - a first output shaft which can be connected to at least one output shaft connection in a torque-transmitting and a first rotational direction-transmitting manner; - a second output shaft which is connectable to said output shaft connection in a torque-transmitting manner and in a second rotational direction opposite to the first rotational direction; - a first partial coupling, by means of which a torque can be releasably transmitted between the motor shaft connection and the first output shaft; - a second partial clutch, by means of which a torque can be releasably transmitted between the motor shaft connection and the second output shaft. The dual clutch is characterized primarily by the fact that a separating clutch is also provided for separating a torque transmission between the first output shaft and the second output shaft.

[0002] For example, for tractor applications or other work equipment, referred to here as commercial vehicles, double clutches with a reversing gear are known, by means of which the direction of rotation of an output shaft can be reversed without load interruption. The functioning of the reversing gear is essentially the same as a powershift dual clutch transmission, like changing gears in a passenger car. Here, however, this powershift clutch enables a change between forward and reverse, for example. If, for example, a wheel loader approaches a load to be transported, picks it up, and then wants to reverse with the load, a load interruption and the associated undefined state is undesirable. The double clutch has at least two (preferably concentric) output shafts to enable forward or reverse travel.

[0003] Cost pressure is high in this segment, and a cost-effective design for such a dual clutch with a reversing gearbox is sought. For example, a so-called dry powershift clutch, instead of a so-called wet clutch, i.e., one with friction partners encased in an oil bath, is significantly more cost-effective. However, this requires the structural separation of the (dry) dual clutch and the (wet) reversing gearbox.

[0004] From DE 10 2015 206 881 A1 a reversing gear is known which can be read in the preamble of claim 1.

[0005] The present invention is based on the object of at least partially overcoming the disadvantages known from the prior art. The features of the invention are set forth in the independent claims, for which advantageous embodiments are presented in the dependent claims. The features of the claims can be combined in any technically reasonable manner, whereby the explanations from the following description and features from the figures, which comprise supplementary embodiments of the invention, can also be considered.

[0006] The reversing gear is characterized in particular by the fact that a separating clutch is provided on the first output shaft for directly separating a torque transmission between the first output shaft and the second output shaft.

[0007] In the following, reference is made to the specified axis of rotation whenever, without explicit indication to the contrary, the axial direction, radial direction, or the direction of rotation and corresponding terms are used. Ordinal numbers used in the preceding and following descriptions serve only to clearly distinguish them and do not reflect the order or ranking of the designated components. An ordinal number greater than one does not necessarily imply that another such component must be present.

[0008] It should be noted in advance that the reversing gear is designed for use in a motor vehicle, preferably a commercial vehicle, for example a tractor or low-floor vehicle, or in a mobile or stationary work device. The reversing gear is designed to transmit a torque from at least one drive motor, which provides its torque via its motor shaft, to an output shaft, specifically in the two opposite directions of rotation relative to the axis of rotation of the output shaft. In one embodiment, the motor shaft and the output shaft are aligned coaxially with one another. Alternatively or additionally, an output shaft is arranged parallel to the motor shaft, for example via a secondary shaft of the transmission gear. In one embodiment, a universal joint is provided, which is preferably arranged downstream of any transmission gears from the perspective of the drive motor.It should be noted that one or more output shafts are provided, for example one for the propulsion of the respective motor vehicle and another as a power take-off (for example PTO).

[0009] It should be noted that (although not necessarily) the motor shaft is a separate component or part of a separate unit (drive machine) and therefore, during use, is or must be connected to the dual clutch proposed here via a motor shaft connection in a torque-transmitting manner. For example, the motor shaft is directly connected to the motor shaft connection of the dual clutch in a torque-fixed manner. Alternatively, the motor shaft is initially connected to a torsional vibration damper (e.g., a dual-mass flywheel, a centrifugal pendulum absorber, a multi-flange damper, and / or a so-called rocker damper). Often, advantageously, the motor shaft connection itself is not a shaft, but rather formed by a clutch basket or clutch cover. The large co-rotating mass is thus located on the motor side, and the transmission gear has a significantly lower co-rotating mass.As explained at the beginning, this is a great advantage, especially for a reversing gearbox.

[0010] Just like the engine shaft, the at least one output shaft is often a separate component or part of a separate unit (transmission gear, differential, consumer gear, or similar). In one embodiment, the respective (then separate) output shaft is therefore not a component of the dual clutch, but is connected to the output shafts in a torque-transmitting, preferably torque-fixed, manner by means of a shaft connection for this separate output shaft (i.e., the output shaft connection). For example, a spline connection is used for this purpose. In one embodiment, at least one of the output shafts is formed integrally with one of the output shafts, for example, a so-called power take-off (PTO), and in this case, the output shaft connection is not the shaft connection for connecting the output shaft, but a shaft connection of the (integrally formed) output shaft.In one embodiment, a shaft connection is formed by a transmission gear.

[0011] The dual clutch proposed here, which is preferably of dry design, comprises a first partial clutch and a second partial clutch, each of which can be closed and opened separately. During a load-free change from one (e.g., first) partial clutch to the other (e.g., second) partial clutch, these are actuated in such a way that, while one partial clutch is still being disengaged, meaning a frictional torque is still present, the other partial clutch is already engaged, meaning a frictional torque can be generated. Due to the opposing directions of rotation of the output shafts (in reversing operation), in this state the other partial clutch rotates opposite to the respective corresponding friction partner of the dual clutch and must therefore first be braked down.Especially with dry dual clutches, the moment of inertia is high due to the structural separation, but also due to the generally larger diameter of the friction pack (compared to a wet dual clutch). This leads to slow response and / or excessive heat generation in the dual clutch.

[0012] Here, it is proposed that, in addition to the two partial clutches, a further separating clutch is provided, by means of which a rigid, i.e. torque-resistant, connection between the output shafts can be released, thus forming a further releasable torque transmission. Such a separating clutch is preferably of simple construction, for example as a separating clutch that can only be switched in synchronous rotation, for example as a so-called claw clutch, as a so-called wedge clutch or as a shift sleeve with a shift wheel of a manual transmission. The wedge clutch has a polygonal cone and a complementary counter-receiver, whereby low relative speeds are permissible during the closing process, for example approximately 20 rpm [twenty revolutions per minute]. Alternatively or additionally, a separating clutch suitable for synchronizing the speed can also be used, for example a friction clutch.

[0013] When the separating clutch is open, the first output shaft and the second output shaft are separated from each other, meaning no torque is transferred. If the direction of rotation is to be reversed under load (i.e. without load interruption) (i.e. in reversing operation), the separating clutch is closed in a gentle operating mode with the torque transfer via the currently inactive (e.g. second) partial clutch still open or sufficiently low. The separating clutch experiences little opposing torque because the associated (e.g. second) partial clutch is open or almost completely open, meaning the corresponding friction partners of this partial clutch are in sufficiently light contact with each other or slipping. This means that a separating clutch that would otherwise only be switchable in synchronous rotation (under load) can be used even without a synchronous speed.With a rapid shift in the double clutch from one (e.g. first) partial clutch to the other (then, for example, second) partial clutch, it is even possible to build up a mass moment of inertia in the other partial clutch, which is now to be accelerated, in order to extract energy from the currently transmitting output shaft with its reversing direction of rotation, preferably already reducing the speed and thus the mass inertia in the system, so that a faster and / or material-saving change of direction can be achieved.

[0014] It should be noted that the shifting process during reversing is somewhat complex and is usually performed automatically, meaning the dual clutch is integrated into an automatic transmission. It should also be noted that reversing is performed at the idle speed of a prime mover and with low torque demand, for example, in a commercial vehicle traveling at low speeds, for example, at or below 5 km / h [five kilometers per hour], preferably no more than 2 km / h.

[0015] A key advantage is that when one of the output shafts is operating (for example, during normal forward travel of a commercial vehicle) with the clutch open, the other clutch (and possibly also the associated other output shaft) is not dragged along. This reduces fuel consumption and allows for faster speed changes.

[0016] It is further proposed in an advantageous embodiment of the double clutch that the separating clutch is formed by a shift sleeve and at least one shift wheel, preferably two shift wheels.

[0017] A separating clutch, such as that used in a conventional manual transmission (e.g., for gearshifting), is proposed here. Such a separating clutch with a shift sleeve is designed for shifting at different speeds while simultaneously operating without load and is therefore particularly suitable for this purpose because the respective partial clutch is (at least almost) open.

[0018] In a design with a single shift gear, only the engagement and disengagement of the relevant sub-clutch and, if applicable, the output shaft is possible. With two shift gears, an additional operating function can be added with the additional shift gear. In one design, a power take-off (PTO) can be connected. This allows a power take-off to be connected to a consumer even while the engine shaft is running (with the relevant shift gear decoupled).

[0019] It is further proposed in an advantageous embodiment of the double clutch that in an operating state by means of the separating clutch a torque can be transmitted from the motor shaft connection to the output shaft connection by means of, preferably exclusively, the second partial clutch in the second rotational direction, and wherein at least one of the following additional operating states can be set by means of the separating clutch: - torque transmission in the first rotational direction from the motor shaft connection to the output shaft connection by means of only the first partial coupling; and - Torque transmission in the first rotational direction or in the second rotational direction from the motor shaft connection to the output shaft connection by means of both the first partial coupling and the second partial coupling.

[0020] In this embodiment, the three operating states described here can be adjusted using the two partial clutches and the respective output shafts by appropriately wiring the separating clutch, for example, using a shift sleeve and two corresponding shift wheels. With a separating clutch with a shift sleeve and two shift wheels, the following positions can be adopted: - Neutral position of the shift sleeve without torque-transmitting connection with the shift wheels, whereby, for example, the first partial clutch and the first output shaft are switched in a torque-transmitting manner for transmitting torque to the output shaft connection (first operating state); - first position of the shift sleeve with torque-transmitting connection to the first shift wheel, wherein, for example, for reversing operation, the first output shaft and the second output shaft are then connected to each other in a torque-transmitting manner (second operating state); and - second position of the shift sleeve with torque-transmitting connection to the second shift wheel, whereby, for example, for transmitting a high torque, both the first output shaft and the second output shaft are connected to the output shaft connection in a torque-transmitting manner for the same direction of rotation (third operating state), i.e. the output shafts run in parallel operation.

[0021] In the third operating state (for example with the shift sleeve in the second position), the previously open other (for example second) partial clutch is preferably closed and the speed is adjusted to that of the motor shaft connection or the currently torque-transmitting (then first) output shaft. It should be noted that (if desired) it is possible to do this without transmitting the full torque, for example by ensuring sufficiently light contact to overcome the inertia of the other (for example second) output shaft of the corresponding friction partners of the other (for example second) partial clutch. The separating clutch is then closed and, if necessary, the full designed torque can now be transmitted at the second partial clutch by fully pressing it together.

[0022] It should be noted that in many operating conditions, the prime mover does not draw its maximum torque, but rather, for example, a maximum of half. It is therefore advantageous to design the gear stages for the first output shaft and the second output shaft (at least for the third operating condition) for such a lower operating torque, for example, half the maximum torque (plus any safety factors), with the third operating condition then being selected when a situation requires the full torque. This allows the downsizing of the transmission components to further reduce mass inertia and thus fuel consumption during normal operation, and also accelerate response times.It should be noted that the loaded components in the torque flow can be protected from excessive torque delivery by means of the (then first) partial clutch (in slip clutch operation) by designing the maximum transmittable torque of the relevant partial clutch to this required maximum torque.

[0023] It is further proposed in an advantageous embodiment of the double clutch that one of the output shafts is designed as a hollow shaft and the other output shaft is guided through the output shaft designed as a hollow shaft, wherein preferably the other output shaft is also designed as a hollow shaft and the motor shaft connection is detachably or permanently connected to the output shaft connection past the partial couplings in a torque-transmitting manner.

[0024] According to a further aspect, a reversing gear for a drive train is proposed, comprising at least the following components: - a double clutch according to an embodiment as described above; - a transmission gear; and - at least one output shaft connection, wherein the motor shaft connection can be connected to the output shaft connection in a torque-transmitting manner by means of the transmission gear and by means of the partial couplings without load interruption in a reversible direction of rotation.

[0025] It is further proposed in an advantageous embodiment of the reversing gear that the transmission gear comprises a secondary shaft arranged parallel to the output shafts, wherein the first output shaft is connected to the auxiliary shaft in a torque-transmitting manner by means of a first gear pair, and wherein the second output shaft is connected to the auxiliary shaft in a torque-transmitting manner by means of at least one second gear pair.

[0026] In this embodiment, a secondary shaft is arranged parallel to the output shafts, for example, a transmission secondary shaft of a multi-shaft gear ratio of the transmission or as an axial extension of such a transmission secondary shaft. The output shafts are each connected to the secondary shaft in a torque-transmitting manner by means of a connection as efficient as possible, for example, a single-stage spur gear connection or a chain drive. For reversing the motor rotation direction to the second rotation direction (in reversing operation), a reverse idler gear, for example, is integrated into a spur gear connection.

[0027] It is further proposed in an advantageous embodiment of the reversing gear that the second output shaft can be connected to the output shaft connection by means of the separating clutch in a switchable torque-transmitting manner either: - with the first direction of rotation, preferably by means of a supporting second wheel pair; or - with the second direction of rotation, preferably by means of a reversing second wheel pair.

[0028] As already described above, the additional function is created here that the second output shaft can be optionally connected to support the first output shaft. Here, it is preferably proposed that a respective gear pair is provided for this purpose, which is part of a (second) partial transmission of the second output shaft or of the second partial clutch. The reversing second gear pair comprises, for example, a reverse idler gear or is designed as a simple chain drive. The supporting second gear pair is preferably identical (at least with regard to the transmission-relevant diameters of the spur gears involved) to the first partial transmission of the first output shaft or of the first partial clutch.

[0029] According to a further aspect, a drive train is proposed, comprising at least the following components: - at least one drive machine with a motor shaft for delivering a torque; - at least one consumer for absorbing a torque; and - a reversing gear according to an embodiment as described above for transmitting a torque between the drive machine and the at least one consumer, wherein the direction of rotation can be reversed without load interruption by means of the reversing gear.

[0030] The drive train proposed here comprises at least one drive machine, one of which is, for example, an internal combustion engine, a starter generator, and / or an electric drive machine. The at least one drive machine forms the torque source of a torque flow, at least in one main state. Furthermore, at least one consumer is included, for example drive wheels of a motor vehicle, which forms the torque sink of the torque flow, at least in one main state. The at least one drive machine and the at least one consumer are connected to one another in a torque-transmitting manner by means of a reversing gear according to an embodiment as described above. Preferably, the only possibility for separating a torque transmission from the at least one drive machine and the at least one consumer is formed by means of the partial clutches and the separating clutch of the reversing gear.By means of the reversing gear, a load-interruption-free reversal of the direction of rotation, in which the torque of the at least one drive motor is made available to the at least one consumer, is enabled. Preferably, a supporting operation by means of parallel operation of the second output shaft or the second partial clutch is also enabled, whereby the co-rotating mass can be reduced in a main state and, at the same time, for a high torque requirement, the maximum available torque can be transmitted by means of the at least one drive motor in total via the two partial clutches. For this purpose, with the result of a reduced co-rotating mass, the maximum transmittable torque is preferably limited via at least one of the partial clutches to a maximum partial torque, which is lower than the (design-based) maximum torque or the maximum torque to be made available via this torque of the at least one drive motor.

[0031] The drivetrain proposed here comprises a reversing gear, which includes a (preferably dry) dual clutch according to an embodiment as described above. This allows costs to be significantly reduced. Alternatively or additionally, the co-rotating mass in the main operating state of the drivetrain (torque transmission exclusively via the first output shaft) can be significantly reduced without limiting the functionality of the reversing gear. Preferably, the co-rotating mass in the main operating state of the drivetrain (transmission of a low, non-maximum torque exclusively via the first output shaft) can also be further reduced by engaging the second output shaft via the separating clutch (in the same direction of rotation) for a maximum torque requirement.

[0032] According to a further aspect, a motor vehicle is proposed, preferably a commercial vehicle, comprising at least one drive wheel and a drive train according to an embodiment as described above, wherein, for propelling the motor vehicle, a torque can be delivered from the at least one drive motor of the drive train to the at least one drive wheel, wherein the direction of rotation of the at least one drive wheel can be reversed without load interruption by means of the reversing gear.

[0033] The motor vehicle is, for example, a commercial vehicle, such as an industrial truck, a wheel loader, an excavator, or a tractor. The motor vehicle has a drive train according to one embodiment as described above. The torque output by the at least one drive engine is output via the reversing gear to the at least one drive wheel (consumer) and preferably additionally via a power take-off (PTO) to an auxiliary consumer, such as a cardan shaft, a cutter bar, or a hydraulic system. In one embodiment, the reversing gear comprises at least one transmission stage and / or a differential. A transmission stage and / or a differential can preferably be connected to one another as separate assemblies, for example by means of separate partial transmission housings.

[0034] The motor vehicle proposed here comprises a drivetrain comprising a reversing gear with a (preferably dry) dual clutch according to an embodiment as described above. This allows costs to be significantly reduced. Alternatively or additionally, the co-rotating mass in the main operating state of the drivetrain (torque transmission exclusively via the first output shaft) can be significantly reduced without limiting the functionality of the reversing gear. Preferably, the co-rotating mass in the main operating state of the drivetrain (transmission of a low, non-maximum torque exclusively via the first output shaft) can also be further reduced by engaging the second output shaft via the separating clutch (in the same direction of rotation) for a maximum torque requirement.

[0035] The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way limited by the purely schematic drawings, whereby it should be noted that the drawings are not to scale and are not suitable for defining proportions. It is shown in Fig. 1: a circuit diagram of a reversing gear not according to the invention with a rigid connection; Fig. 2: a circuit diagram of a reversing gearbox with a separable connection on the first output shaft in neutral position; Fig. 3: a switching diagram of a reversing gear according to Fig. 2 in first switching position; Fig. 4: a switching diagram of a reversing gear according to Fig. 2 and Fig. 3 in second switching position; Fig. 5: a circuit diagram of a reversing gear not according to the invention with a separable connection on the auxiliary shaft in the neutral position; Fig. 6: a circuit diagram of a reversing gear not according to the invention according to Fig. 5 in first switching position; Fig. 7: a circuit diagram of a reversing gear not according to the invention according to Fig. 5 and Fig. 6 in second switching position; and Fig. 8: Schematic plan view of a drive train in a tractor with reversing gear.

[0036] In Fig. 1 shows a shift diagram of a reversing gear 2 not according to the invention with a rigid connection. On the right of the illustration, three gear ratio stages 39 are shown, which, by means of two shift sleeves 13 and associated shift gears 14, 15, connect the motor shaft 23 via the motor shaft connection 4 and the respective output shafts 5, 8 of the dual clutch 1 to the output shaft connection 6 via a parallel auxiliary shaft 18 in a torque-transmitting manner. In the transmission gear 17, a first sub-gear 27 with a first (purely optionally simple spur gear) gear pair 19 is provided for the first output shaft 5, by means of which a torque can be transmitted from the first output shaft 5 to the auxiliary shaft 18.Furthermore, the transmission gear 17 includes a second sub-gear 28 with a second (purely optionally simple spur gear) gear pair 20 for the second output shaft 8, by means of which a torque can be transmitted from the first output shaft 5 to the auxiliary shaft 18. The second sub-gear 28 includes a reverse idler gear 40, so that (with a constant motor rotation direction 29 of the motor shaft 23), the first rotation direction 7 of the auxiliary shaft 18 with torque transmission via the first sub-clutch 10 is opposite to the second rotation direction 9 with torque transmission via the second sub-clutch 11.

[0037] For the sake of completeness, the partial clutches 10, 11 will be briefly explained. The first partial clutch 10 comprises a first counterplate 32 and a first pressure plate 30, which are connected to the motor shaft 23 in a torque-resistant manner and permanently rotate around the rotation axis 3. The first counterplate 32 is axially fixed, and the first pressure plate 30 is arranged to be axially displaceable. A first clutch disc 34 is arranged between the two plates, which, by axially pressing the first pressure plate 30 against the first clutch disc 34 and the first counterplate 32, generates such an axial normal force that a torque can be transmitted by friction. The second partial clutch 11 is constructed (here purely optionally mirrored to the first partial clutch 10) at least functionally in the same way, with an axially displaceable second pressure plate 31, a rigid second counterplate 33, and a second clutch disc 35 arranged between them.The clutch discs 34,35 can only be connected to the motor shaft connection 4 by frictional engagement in order to transmit torque.

[0038] Here (purely optionally), the second output shaft 8, which is torque-fixedly connected to the second clutch disc 35, is designed as a hollow shaft through which the first output shaft 5, which is torque-fixedly connected to the first clutch disc 34, is passed.

[0039] The dual clutch 1 comprises the aforementioned first sub-clutch 10 and the second sub-clutch 11, which are not simultaneously compressed in stable operating states in this configuration. Rather, only for reversing operation is the first sub-clutch 10 in the release process, while the second sub-clutch 11 is in the engagement process, or vice versa. Thus, a torque can be transmitted without load interruption when the direction of rotation 7, 9 is reversed. It should be noted that the clutch disc 35 of the respective non-compressed sub-clutch 11 rotates in an opposite direction of rotation when the other sub-clutch 10 is compressed. The directions of rotation 7, 9 shown here on the auxiliary shaft 18 apply to the compressed state of the respective associated sub-clutch, i.e., the first direction of rotation 7 when the first sub-clutch 10 is compressed and the second direction of rotation 9 when the second sub-clutch 11 is compressed.

[0040] In Fig. 2 is a definition without exclusion of the general public, purely for the sake of clarity, largely identical to that in Fig. 1, an identical dual clutch 1 is shown, so reference is made to the description therein in this regard. The transmission stages 39 and associated shift sleeves 13 are not shown here, but such a transmission device can be connected purely optionally to the first output shaft 5 shown here and the auxiliary shaft 18. Alternatively or additionally, for example, a differential 38 and / or a continuously variable transmission, for example a so-called CVT (continuous variable transmission) with a traction drive or push-link belt, can be connected. For the sake of clarity, an optional output shaft connection 6 is designated on the auxiliary shaft 18.

[0041] In contrast, a (further) separating clutch 12 is provided, which here (purely optionally) is designed with a shift sleeve 13 and shift gears 14, 15. By means of this separating clutch 12, the second output shaft 8 (as shown here) can be separated from the first output shaft 5. Thus, the second output shaft 8 and thus also the second clutch disc 35 do not rotate when the first partial clutch 10 is pressed together. However, the second gear pair 20 of the second partial transmission 28 does rotate. Here, an embodiment is shown in which the second output shaft 8 can also be connected in parallel operation to the first partial transmission 27 by means of a corresponding switching position of the shift sleeve 13. Thus, a (design-based) maximum transmittable torque at the first partial clutch 10 can be limited to a value below the maximum engine torque at the motor shaft 23, and thus the co-rotating mass of this partial clutch can be reduced.

[0042] In Fig. 3 is a circuit diagram of a reversing gear 2 according to Fig. 2 in the first switching position. Reversing operation is now possible here, as the first output shaft 5 and the second output shaft 8 are connected to each other with opposing rotation directions 7, 9 (via the reverse idler gear 40). The load-interruption-free reversal of the rotation direction 7, 9 on the auxiliary shaft 18 can be carried out, for example, conventionally or as explained in the above description.

[0043] In Fig. 4 is a circuit diagram of a reversing gear 2 according to Fig. 2 and Fig. 3 in the second switching position. Here, the second partial transmission 28 is not active, but the second partial clutch 11 (as well as the first partial clutch 10) can be compressed or is simultaneously compressed. Thus, a torque can be transmitted or directed from the motor shaft connection 4 to the output shaft connection 6 via the first partial transmission 27, both via the first partial clutch 10 and via the second partial clutch 11.

[0044] In Fig. 5 is a without exclusion of the general public purely for the sake of clarity largely with the Fig. 2 to Fig. 4, an identical dual clutch 1 is shown, so that reference is made to the description therein in this regard. In contrast, the reversing gear 2 not according to the invention has a separable connection on the auxiliary shaft 18, which is shown here in a neutral position. The first partial gear 27 is (purely optionally) designed identically to that shown in the preceding figures. The reversing second gear pair 20 of the second partial gear 28 is also (purely optionally) designed identically to that shown in the preceding figures. Furthermore, here a supporting second gear pair 21 is also included by the second partial gear 28, which here (purely optionally) is designed at least functionally identically to the first partial gear 27.

[0045] The separating clutch 12 is now arranged on the auxiliary shaft 18 (regardless of the design of the sub-gearboxes 27, 28). This ensures that in the (first) operating state with the first sub-clutch 10 engaged, only the first output shaft 5 and the auxiliary shaft 18 rotate. The second sub-gearbox 28 does not rotate (apart from the shift sleeve 13 of the separating clutch 12). The co-rotating mass is therefore very small in this (first) operating state. This results in a very low mass moment of inertia, with the aforementioned advantages.

[0046] In Fig. 6 is a circuit diagram of a reversing gear 2 not according to the invention according to Fig. 5 is shown in the first switching position. Reversing operation is now possible here, as the first output shaft 5 and the second output shaft 8 are connected to each other with opposing rotation directions 7, 9 (via the reverse idler gear 40). The load-interruption-free reversal of the rotation direction 7, 9 on the auxiliary shaft 18 can be carried out, for example, conventionally or as explained in the above description. It should be noted that the supporting second gear pair 21 of the second sub-transmission 28 is not active here.

[0047] In Fig. 7 is a circuit diagram of a reversing gear 2 not according to the invention according to Fig. 5 and Fig. 6 shown in the second switching position). Here, the reversing second gear pair 20 of the second partial transmission 28 is not active, but the second partial clutch 11 (as well as the first partial clutch 10) can be compressed or is simultaneously compressed. Thus, a torque can be transmitted or is transmitted from the motor shaft connection 4 to the output shaft connection 6 via the first partial clutch 10 by means of the first partial transmission 27 and via the second partial clutch 11 by means of the supporting second gear pair 21.

[0048] In Fig.Figure 8 shows a schematic plan view of a drive train 16 in a tractor 26 with a reversing gear 2. A driver's cab 37 is indicated for a rear axle 42 with rear drive wheels 24, and a front axle 41 with front drive wheels 25 is shown in front of it along the vehicle's longitudinal axis 36. A drive engine 22 is arranged centrally (here purely optionally indicated as an internal combustion engine) and can be connected in a torque-transmitting manner via the reversing gear 2 to a differential 38 on the front axle 41 and a differential 38 on the rear axle 42 to the front drive wheel 25 and the rear drive wheel 24, respectively, so that switching from forward to reverse via the reversing gear 2 is possible without load interruption.

[0049] The dual clutch proposed here enables efficient operation, especially in a cost-effective dry design.

Claims

[1] Reversing gear (2) for a drive train (16), comprising at least one double clutch (1), a transmission gear (17) and at least one output shaft connection (6), wherein the double clutch (1) is designed to releasably transmit a torque about a rotation axis (3), comprising at least the following components: - a motor shaft connection (4); - a first output shaft (5) which can be connected to at least one output shaft connection (6) in a torque-transmitting manner and in a first direction of rotation (7); - a second output shaft (8) which can be connected to said output shaft connection (6) in a torque-transmitting manner and in a second rotational direction (9) opposite to the first rotational direction (7); - a first partial coupling (10), by means of which a torque can be releasably transmitted between the motor shaft connection (4) and the first output shaft (5); and - a second partial coupling (11), by means of which a torque can be releasably transmitted between the motor shaft connection (4) and the second output shaft (8), wherein the motor shaft connection (4) can be connected to the output shaft connection (6) in a torque-transmitting manner by means of the transmission gear (17) and by means of the partial couplings (10, 11) without load interruption in a reversible direction of rotation (7, 9), characterized by that a separating clutch (12) is arranged on the first output shaft (5) for directly separating a torque transmission between the first output shaft (5) and the second output shaft (8). [2] Reversing gear (2) according to claim 1, wherein the separating clutch (12) is formed by a shift sleeve (13) and at least one shift wheel (14, 15), preferably two shift wheels (14, 15). [3] Reversing gear (2) according to claim 1 or 2, wherein in an operating state by means of the separating clutch (12) a torque can be transmitted from the motor shaft connection (4) to the output shaft connection (6) by means of, preferably exclusively, the second partial clutch (11) in the second rotational direction (9), and wherein at least one of the following further operating states can be set by means of the separating clutch (12): - torque transmission in the first rotational direction (7) from the motor shaft connection (4) to the output shaft connection (6) by means of exclusively the first partial coupling (10); and - Torque transmission in the first direction of rotation (7) or in the second direction of rotation (9) from the motor shaft connection (4) to the output shaft connection (6) by means of both the first partial coupling (10) and the second partial coupling (11). [4] Reversing gear (2) according to one of claims 1 to 3, wherein the transmission gear (17) comprises a secondary shaft (18) arranged parallel to the output shafts (5,8), wherein the first output shaft (5) is connected to the auxiliary shaft (18) by means of a first gear pair (19) in a torque-transmitting manner, and wherein the second output shaft (8) is connected to the auxiliary shaft (18) in a torque-transmitting manner by means of at least one second gear pair (20, 21). [5] Reversing gear (2) according to one of claims 1 to 4, wherein the second output shaft (8) can be connected to the output shaft connection (6) by means of the separating clutch (12) in a switchable torque-transmitting manner either: - with the first direction of rotation (7), preferably by means of a supporting second wheel pair (21); or - with the second direction of rotation (9), preferably by means of a reversing second wheel pair (20). [6] Drive train (16) comprising at least the following components: - at least one drive machine (22) with a motor shaft (23) for outputting a torque; - at least one consumer (24, 25) for absorbing a torque; and - a reversing gear (2) according to one of claims 1 to 5 for transmitting a torque between the drive machine (22) and the at least one consumer (24, 25), wherein the direction of rotation (7, 9) is reversible without load interruption by means of the reversing gear (2). [7] Motor vehicle (26), preferably a commercial vehicle, comprising at least one drive wheel (24, 25) and a drive train (16) according to claim 6, wherein, for propelling the motor vehicle (26), a torque can be delivered from the at least one drive motor (22) of the drive train (16) to the at least one drive wheel (24, 25), wherein the direction of rotation (7,9) of the at least one drive wheel (24,25) can be reversed without load interruption by means of the reversing gear (2).

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