WO2016058734A1

WO2016058734A1 - Motor vehicle powertrain

Info

Publication number: WO2016058734A1
Application number: PCT/EP2015/068926
Authority: WO
Inventors: Guenter Ruehle; Christian Abele; Dennis PLITT; Eberhard Schaetzle
Original assignee: Getrag Getriebe- Und Zahnradfabrik Hermann Hagenmeyer Gmbh & Cie Kg
Priority date: 2014-10-13
Filing date: 2015-08-18
Publication date: 2016-04-21
Also published as: DE102014114769A1

Abstract

The invention relates to a powertrain (10) for a motor vehicle, comprising a drive motor (12), the drive power of which can be routed via a power path (22) to driven wheels (20), and comprising a mechanical KERS reservoir (24) which can be connected to the power path (22) by means of a KERS clutch assembly (26). Said KERS clutch assembly (26) comprises a hydrodynamic speed and torque converter (30).

Description

Automotive powertrain

The present invention relates to a drive train for a motor vehicle, with a drive motor whose drive power can be guided via a power path to driven wheels, and with a mechanical KERS memory which is connectable or connected via a KERS coupling arrangement with the power path.

In the field of powertrains for motor vehicles is generally distinguished between classic drive trains with internal combustion engine, hybrid drive trains, which have an internal combustion engine and an electric drive motor, and electric drive trains, the only one Have electric motor as a drive motor. For the operation of the electric motor as a drive motor energy storage are provided, which are usually designed as accumulators or capacitors, but may also be hydrogen-based, for example in conjunction with a fuel cell.

In all these powertrains there may be a need to at least temporarily cache kinetic energy during a braking operation of a vehicle in order to provide this energy at a later time as drive energy can. In drive trains with an electric machine, it is known to operate them as a generator during a braking operation, wherein the electrical power obtained from the kinetic braking energy can be used, for example, to charge accumulators. Such a type of kinetic energy recovery is also referred to as an electrical KERS (Kinetic Energy Recovery System).

Electromechanical KERS systems with very high efficiency while using electric machines in generator mode at relatively high speeds. The rotor of such a generator can also serve as a flywheel, which usually requires that the rotor can be decoupled from the power path. The kinetic energy stored in such a rotor can either be converted directly into kinetic drive energy again as required, but can also be converted into electrical energy by the generator going from an idling mode to a loading mode. In this case, for example, rechargeable batteries or high power capacitors can be charged.

A basically very old way of recovering kinetic drive energy is a so-called mechanical KERS, wherein a rotating

Flywheel system is used as a buffer. Compared to electrical and electromechanical KERS systems, this system is now considered interesting again because the life is virtually unlimited, at least in comparison to electrical storage such as batteries and capacitors, which usually degrade over time, often depending on the number of carried out charging and discharging cycles. From document DE-C-891503 an omnibus drive using a flywheel gyroscope is known. The drive should be particularly useful when the bus is exposed to frequent speed changes. The drive includes a flywheel gyro which can be charged with mechanical energy. Furthermore, the drive train includes an internal combustion engine. The internal combustion engine can drive the bus via a fluid coupling or a hydraulic converter, a change gear and a cardan shaft. An arranged with a vertical axis flywheel is connected via a bevel gear and a hydraulic clutch or a converter to the transmission. By alternately or simultaneously switching on the clutches or transducers, the vehicle can be driven either by the internal combustion engine or by the flywheel gyro or simultaneously by both. If necessary, an overrunning clutch can be interposed between the engine and the transmission. The energy absorption of the flywheel mass gyro takes place either by increasing the drive power of the internal combustion engine or by accelerating the gyro from braking energy.

More recent concepts for using such a flywheel mass memory typically include a continuously variable transmission (CVT) operating between

Flywheel accumulator and drive train (for example, vehicle transmission) can be connected. In such a known drive train (DE 10 2007 033 577 A1), the connection of the flywheel mass storage device to the power path further includes a disconnect clutch. Due to the continuously variable transmission, it should be possible to design the flywheel mass accumulator at high speeds of at least 30,000 rpm, preferably 60,000 rpm. This should make it possible to realize the flywheel mass storage structurally compact. The separating clutch can be provided in order to avoid drag losses or to realize a standstill decoupling.

Another mechanical KERS system with a continuously variable transmission is known from the document DE 10 2010 062 789 A1. The continuously variable transmission or a variator of another type is intended to be used to sum drive power of an electric motor and drive power from a flywheel energy storage suitable. [0009] Document DE 10 2010 009 405 A1 discloses an electromechanical KERS system in which an electrical rotor is mechanically coupled to a shaft of a motor vehicle and in which a flywheel mass body can be magnetically coupled directly to the rotor if required.

The document DE 32 24 982 A1 discloses a further drive train in which drive power of an internal combustion engine and drive power from a flywheel storage via a hydrodynamic torque converter and a freewheel device are superimposed.

A drive train with a flywheel mass storage and a KERS coupling arrangement for connecting the flywheel mass storage device to a power path is known from the document WO 201 1/080512 A1. The KERS clutch assembly used herein includes a memory-side gearset and a power-path-side gearset. The memory-side wheelset and the power-path-side wheelset are coupled together via at least two multi-plate clutches, which can be actuated by means of suitable actuators. About the wheelsets the power path, depending on the clutch is connected with different translation with the flywheel energy storage. One of the translations can be used for loading the flywheel mass memory, the other for unloading the flywheel mass memory.

However, the multiple clutches can also be used in different translations each for loading or unloading. Trained as multi-plate clutches clutches can be designed as a power shift clutches, so that transitions from one to the other clutch can be performed without power interruption.

The power path side wheelset is preferably connected to the input shaft of a motor vehicle transmission. The friction clutches are normally open clutches. To improve the efficiency of the flywheel mass storage device, it is known to arrange such a flywheel in a housing and to evacuate the housing via a vacuum pump in order to keep aerodynamic losses to a minimum. A vacuum pump which can be used for this purpose is disclosed, for example, in the document DE 196 20 368 C1.

The document DE 199 23 154 B4 finally relates to a hydraulic actuation system for an automated transmission, wherein a pump is force-transmitting connected to a drive motor or transmission of the vehicle via a mechanical drive and a freewheel mechanism, wherein the pump also power transmitting with an electric motor connected is. The mechanical drive and the electric motor are connected to a common drive shaft of the pump.

To operate the KERS clutch assemblies described above, it is generally possible to use electrical, pneumatic or hydraulic actuators. In the case of hydraulic actuators, it is also known to use a hydraulic fluid both for the actuation and for the cooling of clutches, in particular friction clutches.

Against the above background, it is an object of the invention to provide an improved automotive powertrain.

[0018] The above object is achieved in the case of the drive train mentioned at the outset in that the KERS clutch arrangement has a hydrodynamic identification converter.

A hydrodynamic identification transducer may be in the form of a transmission for torque and speed conversion or may be in the form of a clutch for speed conversion. In the present case, the term hydrodynamic identification converter is to be equated with the term of the hydrodynamic transmission, so that a hydrodynamic transmission can also be embodied as a pure clutch exclusively for speed conversion. Such a hydrodynamic transmission be able to replace continuously variable transmissions such as solid toroidal transmissions, thrust transmission, etc., as well as fluid-cooled multi-plate clutches. The drive train can set the required translations for loading and unloading the KERS memory in an ideal manner. Also, a fluid coupling at high speeds, in particular differential speeds of primary and secondary, find application. Overall, at least one of the following advantages can be achieved: small space, low weight, good transmission efficiency and / or low cost.

The drive train may be formed as a purely electric drive train, but is preferably a drive train in which a drive motor is formed by an internal combustion engine. The powertrain may additionally include an electric motor to form a hybrid powertrain.

The KERS memory preferably has at least one flywheel. The flywheel is preferably designed for a maximum speed of at least 10,000 rpm, in particular at least 20,000, preferably at least 30,000 rpm. It is particularly preferred if the maximum speed at least

60,000 rpm.

The diameter of the flywheel may be smaller than 500 mm. The flywheel may be accommodated in a storage housing that can be evacuated.

The connection of the KERS clutch assembly with the power path can be done in particular at the entrance of a stepped transmission. The connection can be made directly on the vehicle, but can also be done indirectly on the road. In the latter case, for example, a drive motor could drive an axle of a vehicle, and the KERS memory could be arranged in the region of another axle of the motor vehicle and be driven by this or drive these.

If the KERS memory is connected to an input of a stepped transmission, the ratios of the step transmission (gear steps) can be used to the operation of the KERS memory during charging and discharging to optimize so that it can be brought as quickly as possible at high speeds for example when loading.

If the drive train has an internal combustion engine, a friction clutch assembly and a stepped transmission, then a hydraulic arrangement can preferably also be used to actuate, for example, the friction clutch assembly and / or to actuate the stepped transmission (in the latter case, for example, gear ratios and interpreted) ,

Further, the hydraulic assembly may optionally be used for cooling, of the above-mentioned components of the drive train or of other components, such as an electric machine.

The object is thus completely solved.

The hydrodynamic transmission may be a torque converter, such as a Trilok converter.

Of particular preference, however, it is when the hydrodynamic transmission has a fluid coupling.

In contrast to other hydrodynamic transmissions, a fluid coupling preferably has only two wheels for hydrodynamic coupling, which are generally referred to as the primary part and secondary part or pump and turbine. Such fluid couplings are inexpensive to produce, are robust and have a long life.

Of particular preference is when the fluid coupling is designed as a control clutch whose transmission behavior is adjustable.

The adjustable transmission behavior may be, in particular, the behavior with regard to the transmission of torque and / or relative rotation. be between primary and secondary. The adjustment can be made in particular by the degree of filling of the fluid coupling is adjustable.

Such a fluid coupling, which is preferably free of storage space, can be adjusted in a similar manner with respect to their torque / speed transmission behavior as a wet-running multi-plate clutch.

According to a further preferred embodiment, the degree of filling of the fluid coupling is adjustable, wherein a filling connection of the fluid coupling is connected directly to a pressure port of an electric motor driven KERS pump, so that the degree of filling can be regulated by adjusting the speed of the KERS pump.

Although it is generally also conceivable to control the degree of filling of the fluid coupling using a fluid supply device which adjusts a pressure by means of proportionally acting pressure control valves. However, such proportional valves have very high requirements in terms of purity during assembly.

The regulation of the degree of filling by adjusting the speed of the KERS pump also has the advantage that on the basis of the knowledge of the speed of the pump can be relatively easily turned off on the funded flow.

As a result, the degree of filling can be controlled comparatively easily. In addition, this type of filling does not require high demands during assembly.

According to a further preferred embodiment, the fluid coupling to an emptying port, which is connected to a low-pressure region or connectable.

The emptying connection preferably has a smaller cross-section than a filling connection and, taken alone (or, if several emptying connections are distributed over the circumference, taken together) can have the effect of a throttle or aperture. When controlling the degree of filling of the fluid coupling, the cross-section of the discharge opening (or the discharge openings) can be included in the calculation, such that the degree of filling is a function of the speed of the pump and the throttling function of the discharge port.

According to a further overall preferred embodiment, the drive train on a clutch assembly and / or a gear arrangement which is operated or operated with a hydraulic arrangement, wherein the hydrodynamic transmission is operated with the same hydraulic arrangement.

By way of example, a separate fluid household can be dispensed with by this measure. The clutch assembly and the gear assembly may preferably be formed by a dual-clutch transmission, wherein the clutch assembly may be formed, for example, as a wet-running dual clutch assembly, which is operated and cooled with ATF oil. The gear assembly may be filled with another fluid for lubrication purposes, such as hypoid oil.

The hydrodynamic transmission is preferably operated with the same fluid as the wet-running dual clutch.

The friction clutches of this double clutch can be actuated by so-called pump actuators. A pump actuator also controls the pressure exerted by an actuator on a friction clutch, also not by means of a proportional valve. Rather, a pressure connection of an electric motor-driven pump is directly connected to the actuator, so that the pressure provided by the pump can be regulated by adjusting the speed of the electric motor.

Accordingly, the actuation of the hydrodynamic transmission of the KERS clutch assembly can be done with similar components as used to actuate the transmission input side friction clutch assembly so that cost reductions can be made possible. According to a further overall preferred embodiment, the hydrodynamic transmission has a primary part (also referred to as a pump) and a secondary part (also referred to as a turbine), which are hydrodynamically coupled to one another, the primary part being connected to a KERS wheel of a power path side KERS device. Wheel set is connected and wherein the secondary part is connected to a KERS wheel of a memory-side KERS wheelset.

In this embodiment, the KERS clutch assembly can be coupled in a simple manner, preferably by wheelsets in Stirnradbauweise, to the KERS memory on the one hand and to the power path of the drive train on the other.

On the power path side, this type of connection can be done in particular via a gear wheel of a gear wheel of a transmission arrangement of the drive train, for example, to a gear wheel of a gearset of a partial transmission of a dual clutch transmission. The sub-transmission to which the KERS memory is connected in this way is preferably that which has odd gear ratios, so that a large number of ratios with the highest possible spread for setting operating points is usable, and for loading the KERS- Memory on the one hand and to unload the KERS memory on the other. In this case, the dual-clutch transmission preferably has at least seven forward gear speeds, so that preferably both the forward gear stage 1 and the forward gear stage 7 are available for the connection of the KERS memory.

Furthermore, it is generally preferred if the hydrodynamic transmission has a primary part and a secondary part, wherein the hydrodynamic transmission further comprises a coupling housing which is connected to the primary part or to the secondary part.

In this embodiment, the part connected to the coupling housing forms an outer part of the hydrodynamic transmission, which rotates during operation. The fluid coupling is in this embodiment preferably within a ge closed powertrain housing added. On the coupling housing is preferably located radially outside at least one emptying port.

In this embodiment, the emptying takes place in such a way that, during operation, the hydraulic fluid inside the coupling housing is forced out radially outwards from the emptying connection (or the emptying connections, which are preferably distributed over the circumference of the coupling housing) due to centrifugal forces. In this embodiment, the fluid coupling can be substantially completely emptied when no additional fluid is supplied via the filling port. As a result, the fluid coupling, when not switched into the power flow, can run with essentially no drag torque. As a result, the efficiency of the KERS clutch assembly can be increased.

Furthermore, it is generally advantageous if the hydrodynamic transmission has a primary part and a secondary part, wherein the primary part or the secondary part is connected to a shaft having an axial channel, which couples with a primary part and the secondary part coupling space and with a Filling connection for filling the coupling space is connected.

In this embodiment, the fluid for filling the hydrodynamic transmission can be supplied in a structurally simple manner, wherein the coupling space is in this case in particular filled from radially inward via the axial passage of the shaft.

In the case of an emptying connection located radially on the outside of a coupling housing, a continuous fluid flow thus results in operation from radially inward to radially outward.

This also has the advantage that the hydraulic fluid which is heated during operation is discharged again and again, so that it can be cooled. Consequently, this also achieves good thermal management of the hydrodynamic transmission. Furthermore, it is generally advantageous if the hydrodynamic transmission has a primary part and a secondary part, wherein the hydrodynamic transmission has a coupling housing which is connected to the primary part or to the secondary part, wherein the other part of primary part and secondary part with a shaft is connected, on which the coupling housing is rotatably mounted.

In this case, the shaft can be used to rotatably mount and / or seal the coupling housing (by means of a rotary bearing or by means of a separate shaft seal or the like). By this measure, the coupling housing can be constructed cheaper, especially with less material.

It is advantageous if a KERS wheel of a KERS wheelset is connected to that shaft on which the coupling housing is rotatably mounted, wherein a further KERS wheel of another KERS wheelset is connected to the coupling housing itself.

The KERS wheel set may for example be a memory-side KERS wheel. The additional KERS wheelset may be, for example, a power-side KERS wheelset.

In this construction, a hydrodynamic transmission can be effectively combined with two sets of wheels, which can be designed in particular in spur gear design.

According to a further embodiment, the coupling housing is mounted by means of a first pivot bearing on a drive train housing, wherein the shaft, on which the coupling housing is rotatably mounted, is mounted by means of a second pivot bearing on the drive train housing.

By virtue of this measure, the flow pump can be mounted, as it were, in the manner of a shaft on a drive train housing. It is particularly preferred in a variant when a KERS wheel in the axial direction between the first Pivot and the coupling space is arranged. As a result, an axially compact design is achieved.

Overall, it is also advantageous if a secondary part of the hydrodynamic transmission is fixed or connected via a switchable coupling with an input of a gear arrangement of the drive train.

As already mentioned above, the connection of a secondary part of the hydrodynamic transmission to the input of a gear arrangement makes it possible to use the gear ratios of this gear arrangement for setting operating points of the KERS memory.

According to a further preferred embodiment, which constitutes a separate invention in conjunction with the preamble of claim 1, the KERS clutch assembly in series with the hydrodynamic transmission has a shiftable clutch and / or a vibration damper.

For example, in this embodiment, the KERS memory can be completely disconnected from the power path by means of the switchable clutch. Incidentally, a vibration damper, which is also applicable to the above discussed embodiments, can dampen vibrations such as generated by internal combustion engines in the power train.

[0067] Fluid couplings can be shifted. This advantage can be exploited, in particular, when the KERS clutch arrangement has a plurality of parallel flow couplings which are connected to different wheels of KERS wheelsets. Furthermore, fluid couplings allow high differential speeds, so that the use of flywheels with high speeds is structurally easy to implement.

In addition, the required transmission can optionally be adjusted steplessly by the fluid coupling. When two flow clutches are used in parallel construction, two different translations for the connection between power path and KERS memory can be realized thereby. This makes it possible to both charge and discharge the KERS memory at a selected gear ratio. If the KERS storage is to be charged, then the fluid coupling is preferably filled with the smaller ratio and filled with a fluid volume flow. The flywheel of the KERS memory is thus accelerated to a higher speed and charged with energy. Conversely, if energy from the flywheel of the KERS memory flow in the power path, the clutch with the larger gear ratio is preferably filled with oil controlled. This process can also be carried out under load-controlled by controlled overlapping of the oil filling of this fluid coupling.

Since during a switch-on of the fluid coupling always a differential speed and thus a power loss is present, the fluid coupling can be provided at its outer diameter with throttle bores through which the supplied and heated by the power loss oil is injected and thus an exchange of the oil volume for cooling can be done.

If a fluid coupling is temporarily not needed, the oil supply can be stopped and the fluid coupling can be emptied, for example by radial throttle holes (discharge openings). A fluid coupling without oil filling thus has only a minimal drag torque and causes no further losses.

When dimensioning a fluid coupling whose outer diameter is in the fifth power in the power to be transmitted. The speed of the fluid coupling is in the third power in the power to be transmitted. Consequently, there is a preferred arrangement of the fluid coupling in the transmission system on the speed side with a high speed level. This leads to a smaller diameter of the fluid coupling, and thus also to a smaller filling volume for actuating the fluid coupling, which enables correspondingly short switching times. It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

Embodiments of the invention are illustrated in the drawings and will be explained in more detail in the following description. Show it:

Fig. 1 is a schematic representation of a first embodiment of a drive train according to the invention;

FIG. 2 shows a schematic representation of a KERS clutch arrangement for a drive train according to the invention; FIG.

3 shows a schematic representation of a further embodiment of a drive train according to the invention;

4 shows a schematic longitudinal sectional view through a further embodiment of a KERS clutch arrangement for a drive train according to the invention; and

Fig. 5 is a schematic representation of another embodiment of a drive train according to the invention.

In Fig. 1, a drive train for a motor vehicle is shown in schematic form and generally designated 10. The powertrain 10 includes a drive motor 12, such as an internal combustion engine or a hybrid drive unit, and a friction clutch assembly 14 connected thereto. An output of the friction clutch assembly 14 is connected to a transmission assembly 16, which is preferably a stepped transmission. An output of the gear assembly 16 is connected to a differential 18, by means of which drive power can be distributed to driven wheels 20L, 20R. By the elements mentioned, a power path 22 of the drive train 10 is established. The friction clutch assembly 14 and the transmission assembly 16 may be formed for example by a dual-clutch transmission, wherein the friction clutch assembly 14 preferably has a dual clutch with two wet-running multi-plate clutches. The gear assembly 16 has in this case two partial transmissions, one of which is assigned to the odd gear ratios and the other the even gears. The transmission arrangement preferably has at least seven forward gear speeds and at least one reverse speed step.

The drive train 10 further includes a KERS memory 24, which is designed as a mechanical KERS memory, in particular in the form of a flywheel. The KERS memory is connected via a KERS clutch assembly 26 to the power path 22, in particular to an input of the gear assembly 16. The connection can, as shown, take place on an input shaft of the gear assembly 16, but can also be connected to a gear Wheel of a gear set of one or both partial transmissions of the dual clutch transmission done.

However, it is understood that the drive train 10 may also have a simple friction clutch and a simple multi-step transmission, such as an automated transmission, or a manual transmission.

The KERS clutch assembly preferably has a hydrodynamic transmission. This may be formed by a torque converter, such as a Trilok converter, or by a fluid coupling. Preferably, the hydrodynamic transmission is formed by a fluid coupling 30, as shown in Fig. 1.

The fluid coupling 30 has a primary part (pump) 32 and a secondary part (turbine) 34. Since the fluid coupling 30 allows power to flow in both directions, that is, from the KERS memory 24 to the power path 22 and vice versa, the above designations of the parts of the fluid coupling 30 are for purposes of illustration only. The primary part 32 and the secondary part 34 are in particular designed as wheels, which allow a hydrodynamic coupling between them, as is well known.

The fluid coupling 30 further comprises a coupling housing 36, which is preferably connected to one of the two parts of the fluid coupling 30, in Fig. 1 with the secondary part 34. The coupling housing 36 engages over the other part (in Fig. 1, the primary part 32nd ) and is preferably sealed against a shaft of the primary part 32.

In the interior, a coupling space 38 is formed between the primary part 32 and the secondary part 34, which can be filled with a hydraulic fluid.

The fluid coupling 30 can be used with a fixed filling volume. Preferably, however, the fluid coupling 30 is an actuating clutch with a variable transmission behavior. The variable transmission behavior is achieved in particular by a variable degree of filling.

For this purpose, the flow coupling 30 is assigned a filling connection 40. Although the filling space 40 that can be filled via the filling connection 40 could also be emptied again via the filling connection 40 itself.

However, it is preferred if the fluid coupling 30 has at least one emptying port 42, via which the coupling chamber 38 can be emptied radially outward, namely towards a low-pressure region 44.

The secondary part 34 is connected to a shaft 46 which has an axial channel 48. The shaft 46 is connected to the power path 22, in particular to the input 28 of the gear assembly 16. The primary part 32 is connected to a further shaft 49. The further shaft 49 is connected to a rotation axis of the KERS memory 24. The shaft 46, which has the axial channel 48, in this case forms the filling port 40, so that hydraulic fluid can be supplied via the axial channel 48 into the coupling space 38 in order to fill the fluid coupling 30.

For this purpose, a hydraulic arrangement 50 is provided, which is likewise connected to the low-pressure region 44 (for example in the form of a tank) and via which a hydraulic fluid volume flow can be generated which is fed to the filling port 40.

As shown at A in FIG. 1, the hydraulic assembly 50 may also be used for adjusting or lubricating purposes of the gear assembly 16 and / or (not shown) of the friction clutch assembly 14. For example, the hydraulic assembly 50 may be used to cool the friction clutch assembly 14 and actuate a wet-running multi-disc clutch included therein. The operation is preferably carried out by means of a single-acting hydraulic cylinder whose individual hydraulic connection is connected directly to a pressure connection of an electric motor-driven pump, such that the pressure of the hydraulic cylinder can be regulated by adjusting the speed of the electric motor driving the pump. In particular, in this variant, which is not shown in detail in Fig. 1, no proportional valves between such a hydraulic cylinder and a pump arranged so that this actuator can be realized with low demands on the purity during assembly ("pump actuator").

In the following figures, further embodiments of powertrains for motor vehicles and components thereof are described, which generally correspond in terms of structure and operation of the drive train and the components of FIG. 1. The same elements are therefore identified by the same reference numerals. The following section essentially explains the differences.

FIG. 2 shows another embodiment of a KERS clutch assembly 26 '. The fluid coupling 30 'used here, as in the previous embodiment, a primary part 32 and a secondary part 34, wherein a coupling housing 36th is connected to the secondary part 34. Furthermore, the fluid coupling 30 'has a coupling space 38. The coupling housing 36 has radially outer emptying ports 42.

The primary part 32 is fixed to a hollow shaft 46, which, as in the previous embodiment, an axial channel 48 which forms a filling port 40 for the coupling space 38. On an outer periphery of the shaft 46, a power path side KERS wheel 56 is set.

The secondary part 34 is connected to a shaft 49 having a hollow shaft portion, within which the shaft 46 is rotatably mounted. Further, the shaft 49 is connected to a memory side KERS wheel 54.

The memory-side KERS wheel 54 may be part of a memory-side KERS wheelset. Correspondingly, the power path side KERS wheel 56 may be part of a power path side KERS wheelset.

FIG. 2 further shows an alternative embodiment of a hydraulic assembly 50 '. The hydraulic assembly 50 'has a pump 58 which is drivable by means of an electric motor 60, wherein the rotational speed of the electric motor 60 is denoted by n. The pump 58 has a pressure port 62, which is connected directly to the filling port 40 of the fluid coupling 30. A suction port of the pump 58 is connected to the low pressure region 44.

With the knowledge of the delivery rate of the pump 58 and the cross-sections of the supply lines to the coupling space 38 and the cross sections of the discharge openings 42 can be determined from the speed or the revolutions performed of the electric motor 60, the degree of filling of the fluid coupling 30 'in a simple manner. In general, it is still conceivable to provide a pressure sensor 64 at the connection between the pressure connection 62 and the filling connection 40. This is purely optional.

3 shows a further embodiment of a drive train 10 ". The drive train 10" has a friction clutch arrangement 14 with a first friction clutch 70 and a second friction clutch 72, which can each be designed as wet running multi-plate clutches. Further, the transmission assembly 16, a first partial transmission 74 for forward gears 1, 3, 5, 7 and a second partial transmission 76 for forward gears 2, 4, 6 and a reverse gear R and a parking lock gear P on. The gear assembly 16 includes an input shaft assembly 78 of an inner shaft and a hollow shaft. The inner shaft forms an input shaft for the first partial transmission 74. The hollow shaft forms an input shaft for the second partial transmission 76.

Further, the gear assembly 16 has a first output shaft 80 and a second output shaft 82 which are connected via an unspecified output gear set with an input member of a differential 18. Die erste Ausgangswelle 80 und der zweiten Ausgangswelle 82 sind in der Zeichnung dargestellt. With such a three-shaft arrangement, an axially compact design can be achieved, which is particularly suitable for installation front-transverse in a motor vehicle.

At the input shafts of the input shaft assembly 78 fixed wheels of the gear wheelsets are generally arranged. Idler gears of the respective gear wheelsets are rotatably mounted on the output shafts 80, 82 and switchable by means of respective unspecified clutches in the power flow.

A hydraulic assembly 50 "may be used to operate the friction clutch assembly 14 as well as to operate the KERS clutch assembly 26". Further, the hydraulic assembly 50 "may be connected to a storage housing 84 of the KERS storage 24" to evacuate it, for example. A storage housing 84 within which a flywheel is mounted and which is evacuable, allows operation of the KERS memory with a significant reduction in aerodynamic losses. In general, the hydraulic assembly 50 "may also be connected to the gear assembly 16, but this is not necessarily.

3 further shows that the KERS memory 24 "may comprise a planetary gear in the form of a planetary gear set 86, wherein a ring gear of such a planetary gear set is preferably fixed with respect to a housing of the drive train however optional.

The KERS clutch assembly 26 "includes a KERS pinion 90 coaxial with the KERS memory 24 and connected either to an axis of rotation of a flywheel or to an output member of the planetary gear set Engaging with a first memory-side KERS wheel 92. A second memory-side KERS wheel 94 engages the first memory-side KERS wheel 92. The KERS pinion 90, the first and second KERS memory-side wheels form a memory-side KERS gearset 95th

[0010] The KERS clutch assembly 26 "further includes a first power path side KERS wheel 96 coaxial with the first memory side KERS wheel 92 and engaged with a second power path side KERS wheel 98. The second one Power path side KERS wheel 98 is arranged coaxially with second memory side KERS wheel 94. First and second power path side KERS wheels form a power path side KERS gear set 99.

Between the first memory-side KERS wheel 92 and the first power-path-side KERS wheel 96, a first KERS clutch 100 is arranged.

Between the second memory-side KERS wheel 94 and the second power-path-side KERS wheel 98, a second KERS clutch 102 is arranged.

The arrangements of a memory-side KERS wheel, a clutch and a power-path-side wheel can each be formed by the fluid coupling 30 ', as shown in FIG. 2, wherein the KERS wheels 54, 56 shown there are the KERS motors. Wheels 92, 94 and 96, 98 can form. In this respect, the KERS couplings 100, 102 may each be formed by fluid couplings. It is understood that for actuation or for filling these fluid couplings each own electric motor driven pumps may be provided, as shown in Fig. 2. The fluid couplings can be operated overlapping, so that a change of the paths over which the KERS memory 24 "is coupled to the power path, can be done under load.

The first power-path-side KERS wheel 96 engages via a pinion gear 104 with a gear wheel 106 of a gear wheel set of the gear assembly 16. As shown in FIG. 3, the gear wheel 106 may be a non-rotatably connected to an input shaft of the dual clutch transmission, which is in engagement with a loose wheel, which is associated with a gear stage. In the present case, the fixed gear 106 is in engagement with the idler gears of the forward gear stages 5 and 7, so that a double use or dual use is set up. In Fig. 3 is also shown schematically that, for example, the clutch of the forward gear stage 1 can be inserted so that the power flow of the KERS clutch assembly 26 "on the idler 104, the gear wheel 106 and the forward gear 1 associated wheelset and its switched clutch takes place, so that power is then transmitted via the first output shaft 80 to the output gear to the differential 18 and vice versa.

In the present case, the connection of the KERS clutch assembly 26 "to a gear wheel 106 of the first partial transmission 74. It is understood that the connection can also be made to a gear wheel of the second partial transmission 76, and that alternatively or accumulatively. In the latter case, the KERS clutch assembly 26 "could, for example, have another power path side wheelset which is connected to a gear wheel of the second sub-transmission 76, via another intermediate gear 104 or directly.

FIG. 4 shows a further embodiment of a KERS clutch arrangement 26 "with a fluid coupling 30", which generally corresponds in terms of structure and mode of operation to the fluid coupling 30 'of FIG. 2. The same elements are therefore denoted by the same reference numerals. The following section essentially explains the differences.

As shown in Fig. 4, the shaft 46 has an axial passage 48 which has at least one radial bore in axial alignment with the fluid coupling 30 "to connect the axial passage 48 to the coupling space 38. The shaft 46 is is supported radially with respect to the shaft 49 via a rotary bearing (not designated in any more detail). The shaft 49 has an axial bore which is closed at its end in a fluid-tight manner.

The shaft 49 is rotatably supported by a first pivot bearing 1 12 with respect to a drive train housing 1 10. At the other axial end, the shaft 46 is rotatably supported by means of a second pivot bearing 1 14 with respect to the drive train housing 1 10. The fill port 40 "may be formed on the powertrain housing 110, with a passageway disposed in the powertrain housing 110 axially aligned with the axial passage 48 to introduce fluid into the axial passage 48.

Further, the coupling housing 36 is rotatably supported with respect to the shaft 46, by means of a third pivot bearing 16.

The KERS wheel 56 may be integrally formed with the shaft 46, as shown.

The KERS wheel 54 may be arranged in the axial direction between the first pivot bearing 1 12 and the coupling housing 36 and / or may be fixed to an outer circumferential portion of the coupling housing 36.

Fig. 5 shows another embodiment of a drive train 10 "'having a KERS memory 24"' in the form of a flywheel, which is rotatably mounted with respect to a not-shown drive train housing. A rotary shaft of the KERS memory 24 "'is connected to an input member of a Trilok converter 120, whose stator is not shown in detail in Fig. 5. An output member of Trilok converter 120, which forms part of the KERS clutch assembly 26 "'and also forms a hydrodynamic transmission 30"', is connected to an input member of a clutch 122, which may be formed as a dog clutch. An output member of the clutch 122 is connected to a transmission-side KERS wheel 99 "', via which a connection of the KERS memory 24"' can be made to a gear arrangement, for example to an input of a dual-clutch transmission.

Claims

claims

1 . A drive train (10) for a motor vehicle, comprising a drive motor (12) whose drive power can be guided via a power path (22) to driven wheels (20) and with a mechanical KERS memory (24) which is connected via a KERS clutch arrangement ( 26) is connectable to the power path (22), characterized in that the KERS clutch assembly (26) has a hydrodynamic identification converter (30).

2. Drive train according to claim 1, characterized in that the hydrodynamic identification converter has a fluid coupling (30).

3. Drive train according to claim 2, characterized in that the fluid coupling (30) is designed as a control clutch whose transmission behavior is adjustable.

4. Drive train according to claim 2 or 3, characterized in that the degree of filling of the fluid coupling (30) is adjustable, wherein a filling port (40) of the fluid coupling (30) directly to a pressure port (62) of an electric motor driven KERS pump (58). is connected so that the degree of filling by adjusting the speed (n) of the KERS pump (58) is adjustable.

5. Drive train according to one of claims 2-4, characterized in that the fluid coupling (30) has an emptying port (42) which is connected to a low-pressure region (44) or connectable.

6. Drive train according to one of claims 1-5, characterized in that the drive train (10) has a coupling arrangement (14) and / or a gear arrangement (16) which is operated with a hydraulic arrangement (50), wherein the hydrodynamic identification converter (30) is operated with the same hydraulic arrangement (50).

7. Drive train according to one of claims 1 - 6, characterized in that the hydrodynamic identifier converter (30) has a primary part (32) and a secondary part (34), which are hydrodynamically coupled to each other, wherein the primary part (32) with a KERS- Wheel (56) of a power-side KERS wheelset (99) is connected and wherein the secondary part (34) with a KERS wheel (54) of a memory-side KERS wheelset (95) is connected.

8. Drive train according to one of claims 1-7, characterized in that the hydrodynamic identification converter (30) has a primary part (32) and a secondary part (34), wherein the hydrodynamic transmission (30) has a coupling housing (36) with the primary part (32) or with the secondary part (34) is connected.

9. Drive train according to one of claims 1-8, characterized in that the hydrodynamic identifier converter (30) has a primary part (32) and a secondary part (34), wherein the primary part (32) or the secondary part (34) with a shaft ( 46) having an axial passage (48) connected to a coupling space (38) coupling the primary part (32) and the secondary part (34) and to a filling port (40) for filling the coupling space (38).

10. Drive train according to one of claims 1-9, characterized in that the hydrodynamic identification converter (30) has a primary part (32) and a secondary part (34), wherein the hydrodynamic identification converter (30) has a coupling housing (36) with the primary part (32) or with the secondary part (34) is connected, wherein the other part of the primary part and secondary part is connected to a shaft (46) on which the coupling housing (36) is rotatably mounted.

1 1. Drive train according to claim 10, characterized in that a KERS wheel (56) of a KERS wheel set is connected to the shaft (46), wherein another KERS wheel (54) of another KERS wheelset is connected to the coupling housing (36).

12. Drive train according to claim 10 or 1 1, characterized in that the coupling housing (36) by means of a first pivot bearing (1 12) on a drive train housing (1 10) is mounted, wherein the shaft (46) by means of a second pivot bearing (1 14 ) is mounted on the drive train housing (1 10).

13. Drive train according to one of claims 1 - 12, characterized in that a secondary part (34) of the hydrodynamic identification converter (30) fixed or via a clutch to an input (28) of a gear assembly (16) of the drive train (10) is connected.

14. Drive train according to one of claims 1 - 13 or according to the preamble of claim 1, characterized in that the KERS clutch assembly (26) in series with the hydrodynamic identification converter (30 "') a switchable clutch (122) and / or a Vibration damper has.