WO2020030212A1

WO2020030212A1 - Electromechanical drive arrangement for a motor vehicle

Info

Publication number: WO2020030212A1
Application number: PCT/DE2019/100629
Authority: WO
Inventors: Andrea Reichert; Martin Dressel
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2018-08-10
Filing date: 2019-07-05
Publication date: 2020-02-13
Also published as: DE102018119484A1

Abstract

The invention relates to an electromechanical drive arrangement having an electromechanical main drive motor (E) which comprises a rotor (ER) and a stator (ES), a reduction gearbox device (G), which comprises a gearbox input, a gearbox output, at least one a reduction stage and a gearbox housing which accommodates the reduction stage, an axle differential (AD), for branching off the drive power conducted via the reduction stage, to a first and a second wheel drive train section, and a secondary assembly (AUX1) which can be driven by means of the main drive motor, wherein the secondary assembly is completely or at least partially integrated into the gearbox housing, a first shift element (SEI) and a second shift element are provided in the gearbox housing, the first shift element is embodied and integrated into the drive arrangement in such a way that the drive connection between the rotor and the axle differential can be closed and disconnected by shifting using this shift element, and the second shift element (SE2) is embodied in such a way that a drive connection between the secondary assembly and the rotor can be produced using said shift element, and the secondary assembly can be driven via the axle differential if the drive connection between the rotor and the axle differential is cancelled using the first shift element.

Description

Electromechanical drive arrangement for a motor vehicle

Field of the Invention

The invention relates to an electromechanical drive arrangement for a motor vehicle with an intended for the drive of the motor vehicle electromechanical main drive motor, which comprises a rotor and a stator, a reduction gear device, which is kinematically coupled to the rotor, an axle differential gear, for branching the United at the output of the reduction gear device drive power applied to a first and a second wheel drive section and at least one ne benaggregat eg in the form of a power steering pump, an air conditioning compressor or a pump for a coolant circuit guided via a battery module, that auxiliary unit being drivable via the main drive motor.

From DE 10 2012 010 171 A1 an electromechanical drive arrangement of the type mentioned above is known. In this known drive arrangement, the main drive motor is composed of two coaxial sub-motors, the outputs of which are guided to two separate inputs of an epicyclic gear train. The auxiliary unit provided in this drive arrangement is arranged coaxially to the axis of the inner sub-motor and kinematically coupled to its rotor.

Object of the invention

The invention has for its object to show solutions by which it is possible to create an electromechanical drive arrangement for a purely electrically powered motor vehicle, which is characterized by an advantageously realizable overall structure and which can be operated advantageously from an energy point of view.

Solution according to the invention

The above object is achieved by an electromechanical drive arrangement with:

an electromechanical main drive motor comprising a rotor and a stator, a reduction gear device which comprises a transmission input, a transmission output, at least one reduction stage and a transmission housing which houses the reduction stage,

- An axle differential gear for branching the drive power performed on the reduction stage to a first and a second wheel drive section and

- An accessory that is driven by the main drive motor, wherein

the auxiliary unit is fully or at least partially integrated into the gear housing,

- A first shift element and a second shift element are provided in the gear housing,

the first switching element is designed and integrated into the drive arrangement such that the drive connection between the rotor and the axle differential gear can be closed and disconnected via this,

the second switching element is designed in such a way that a drive connection between the auxiliary unit and the rotor can be established, and

the auxiliary unit can be driven via the axle differential when the drive connection between the rotor and the axle differential is canceled via the first switching element.

This makes it possible in an advantageous manner to provide a drive arrangement for a purely electro-mechanically operated motor vehicle, in which the auxiliary unit and the axle differential gear can be coupled via two switching devices provided in the gearbox in accordance with the switching events generated by a control unit, so that the auxiliary unit in Ferry operation of the vehicle is connected to the drive train section leading to the axle differential and, when the vehicle is at a standstill, the auxiliary unit can still be driven by the main drive motor.

The first switching element is preferably designed and integrated into the drive arrangement such that it can be brought into a state in which the drive connection between the rotor and the axle differential gear is canceled and the auxiliary unit is driven in the vehicle overrun mode via the axle differential gear. For this purpose, a positive or frictional clutch device and / or a freewheel device can be provided in the first switching element. The second switching element is preferably also designed as a coupling device with positive or frictional coupling, and a free-wheel device can also be provided there. According to a further aspect of the present invention, an electronic control device is provided, the switching state of the first switching element and the second switching element being set via this control device, the control device taking into account the current operating state of the vehicle and the switching state of the two lying in the interior of the transmission housing Sets switching elements in accordance with a control concept that takes total energy efficiency into account. The control device can take into account the current or a modeled thermal state of the battery system, the thermal energy required to heat the vehicle interior, the cooling power requirement and the energy requirement of the auxiliary unit, and then, based on this input information, bring about switching states on the two switching elements that cause, for example, overrun operation of the Vehicles that can be tapped from this energy are used as efficiently as possible and without conversion losses to cover the energy requirements of the auxiliary unit. The control device can take into account the speeds at which the unit would be driven when the second switching element was switched through and, for example, first undertake energy regeneration in parallel with the operation of the auxiliary unit via the temporarily drive-operated main drive motor, and then only at slower run-down speeds of the vehicle then the tapped one Use power primarily for the drive of the auxiliary unit. Mixed states can also be temporarily set in which, in overrun mode, both a direct mechanical drive of the auxiliary units takes place from the overrun power tapped from the axle differential and, in addition, recuperation is carried out via the electric motor. The recuperation power can be tuned here by actuating the electric motor, for example in accordance with a deceleration request specified by the driver or an assistance system. For example, if there is a delay request below the braking effect of the auxiliary unit, recuperation takes place via the electric motor, then the recuperation power is reduced at the moment when the auxiliary unit is switched on so that the unit is coupled essentially without jerks, with a further increase in the required deceleration effect again the recuperation output can be increased in a dosed manner. The control device can, in particular, be designed and configured such that when the auxiliary unit requires power, it is covered primarily by power tapping from the axle differential gear when the vehicle is coasting.

The auxiliary unit is preferably designed such that this auxiliary unit has an input shaft and this input shaft is arranged coaxially with the axis of rotation of the rotor of the electromotive. The auxiliary unit can be fully integrated into the gear housing, it can also have a housing section which is part of the Auxiliary unit encloses and which, together with a section of the gearbox housing, then forms the housing of the auxiliary unit.

The drive arrangement according to the invention can also be designed such that the input shaft of the auxiliary unit is arranged parallel to the axis of rotation of the rotor of the electric motor. The power transfer can then be accomplished by a drive train section running in the transmission housing, in particular in the form of a belt drive. The drive arrangement can also be designed such that it comprises two auxiliary units and one of the auxiliary units with its input shaft is coaxial with the rotary axis of the rotor and the second auxiliary unit is arranged offset parallel to this rotary axis.

The first switching element is preferably designed such that a drive connection to the axle differential gear can be produced and canceled via this. The first switching element is preferably arranged between the electric motor and the reduction stage or integrated into the reduction stage. The second switching element is designed in such a way that the drive connection between the rotor and the input shaft of the auxiliary unit can be produced or separated therefrom.

The reduction stage can be designed as a spur gear stage which has a spur gear which is arranged coaxially with the rotor axis, the power transfer to the axle differential transmission then again preferably being effected by the second spur gear. The first switching element can be seated in one of the spur gears, in particular the spur gear that is axial to the rotor axis.

The reduction stage can also be designed as an epicyclic gear and here again it can be designed such that it offers at least two different transmission ratios in a switchable manner.

As already mentioned above, it is possible to effect the kinematic coupling of the auxiliary unit to the electric motor via a belt drive running in the transmission housing, this belt drive being driven in particular as an oil-wetted belt or as a chain drive. The parallel offset of the axles of the auxiliary unit and the rotor can also be brought about by a sequence of laterally intermeshing spur gears. The drive arrangement can also be designed in such a way that it includes a freewheel device, whereby this freewheel device can be designed in such a way that, when the vehicle is overrun, the input shaft of the auxiliary unit is driven by the energy that can be tapped from the axle differential and thereby the rotor shaft "Overtakes", ie rotates at a higher speed.

The first switching element and also the second switching element are preferably designed as positive and / or frictionally coupling switching elements. The respective switching element can also be designed as a transmission device, the switching state of which by fixing / releasing a transmission element, e.g. a ring gear is adjustable.

The reduction gear device can also be designed as a multi-stage switchable gear device. The drive arrangement according to the invention is a purely electrical drive arrangement in which the main drive power is provided by the electric motor. The drive arrangement does not include an internal combustion engine. The electric motor can be manufactured in an advantageous manner as an initially independent assembly and then connected to the gearbox housing as part of the assembly of the drive arrangement. It is also possible to provide at least part of the motor housing, in particular in the form of a pot housing section, through the gear housing.

The axle differential gear can be constructed so that it includes its own differential gear housing which is then connected directly to the housing of the reduction gear device. It is also possible to accommodate the axle differential gear housing in the gearbox, or to manufacture the axle differential gear housing integrally with the housing of the reduction gearbox.

The inventive concept allows the same units such as water pump, air conditioning compressor and power steering pump to be operated in an energetically advantageous manner when the vehicle is at a standstill and in overrun mode. The present invention proposes a novel connection of the auxiliary units. This consists in the connection of the auxiliary units in or on the transmission in connection with two "intelligent" switching elements, which make it possible to connect the auxiliary units depending on the operating state of the vehicle and / or the drive motor (s) and / or the battery charge state and / or of external factors (e.g. temperature) to always operate in the most energy-efficient mode. This is ensured by the fact that the auxiliary units are driven via the gear shaft when the vehicle is moving. In particular, the kinetic energy of the driving stuff can be used. The mechanical drive also offers significant advantages in the overall efficiency chain compared to purely electrified units. When the vehicle is stationary, the second switching element drives the auxiliary unit electrically via the direct connection to the electric motor. The connection of the units to the transmission shaft is released via the first switching element, thereby reducing friction losses. This operating mode makes it possible to provide comfort functions such as stationary air conditioning when the vehicle is stationary or to ensure the necessary functions such as operation of the battery cooling circuit via a water pump for after-cooling after the vehicle has been switched off.

The concept according to the invention enables energy consumption to be reduced by auxiliary units in purely electrically driven vehicles and leads to an increase in the vehicle range.

According to the invention, the drive arrangement of an electric vehicle comprises a purely electric drive machine with a transmission and at least one auxiliary unit. The transmission can only contain the final drive and the differential in accordance with the representations described below, but alternatively it can also have further transmission stages, in particular a preliminary stage.

At least one auxiliary unit integrated either in the drive unit or in the transmission is coupled to the electric drive machine via the second switching element. At least two “paths” can be switched using the two switching elements. Only the gearbox is supplied with power via the first path. The power flows to the auxiliary unit via a second path (when the vehicle is stationary). Via e.g. With a freewheel or special design of the second switching element, a third path can be achieved in overrun mode, power flows from the differential directly to the auxiliary unit (drive via the gear shaft).

The concept of the invention can be realized in different configurations. For example, the rotor axes of the electric drive machine and the auxiliary unit can be arranged coaxially to one another or parallel to the axis. In the case of the axially parallel arrangement, there is a gear connection between the rotor axis of the electric drive machine and the rotor axis of the auxiliary unit. A second or further auxiliary unit are optionally arranged coaxially or axially parallel to one another and connected to one another via a further gear stage. Auxiliary units arranged parallel to each other te can be connected to one another in a geared manner, for example, via a traction mechanism drive. Switching elements can also be provided within the system section that kinematically couples the ancillary units, in particular the traction mechanism drive, which in turn enables a selective coupling and uncoupling of the ancillary units.

In essence, the invention is directed to the drive train of an electric vehicle with an electric drive machine which accomplishes the main drive of the vehicle, with a transmission and with at least one auxiliary unit. In a simple design, the gearbox can only contain one final drive and the differential. The transmission can alternatively also have other transmission stages. The at least one auxiliary unit is integrated in the housing of the drive unit or the transmission. The electric drive machine is coupled to the transmission via a first switching element. A second switching element is arranged between the transmission and the auxiliary unit. The electric drive machine, the switching elements and the auxiliary unit are preferably arranged coaxially. The switching elements are preferably directly connected in series with a view of the drive of the auxiliary unit by means of the electric drive machine. The rotor axes of the electric drive machine and the auxiliary unit can also be arranged axially parallel. In the case of an axially parallel arrangement, a gear connection is formed between the rotor shafts (preferably a rotating medium drive). Two auxiliary units are preferably arranged axially parallel to one another and optionally connected to one another via a transmission medium drive.

Brief description of the figures

Further details and features of the invention will become apparent from the following description in conjunction with the drawing. Show it:

1 shows a first schematic representation to illustrate the construction of an electromechanical drive arrangement according to the invention with an integrated in the gear housing and at the same time arranged to the electric motor ancillary, and a selective coupling of the electric motor with the leading to the axle differential drive train section provided first switching element and one between the electric motor and the auxiliary unit provided second switching element; Figure 2 is a second schematic representation to illustrate the structure of an inventive he electromechanical drive assembly with an integrated in the gear housing and at the same time arranged to the electric motor ancillary unit, and a selective coupling of the electric motor with the drive train section leading to the axle differential section provided here in a spur gear of the Redukti onsgetriebes sits and an otherwise provided between the electric motor and the auxiliary unit second switching element;

Figure 3 shows a third schematic to illustrate the structure of an electromechanical drive arrangement according to the invention also with an auxiliary unit integrated into the transmission housing, and a first and a second switching element for the selective coupling of the axle differential and the auxiliary unit with the electric motor, but here the auxiliary unit is arranged offset parallel to the axis with respect to the rotor axis of the electric motor;

Figure 4 is a fourth schematic illustration to illustrate the structure of an electromechanical drive arrangement according to the invention with two internal gear shift elements and now with two auxiliary units integrated in the gear housing, one of the auxiliary units being arranged coaxially with the rotor axis of the electric motor and the further auxiliary unit being axially offset in parallel ;

FIG. 5 shows a fifth schematic representation to illustrate the structure of an electromechanical drive arrangement according to the invention with an auxiliary unit integrated into the gear housing and axially parallel to the electric motor, both the coupling element serving to couple the axle differential to the electric motor and the coupling element of the auxiliary unit to the electric motor serving second switching element are arranged in an intermediate region between the electric motor and the reduction gear stage in the gear housing;

FIG. 6 shows a sixth schematic representation to illustrate the coupling states of the switching elements of the drive arrangement according to the invention in the case of different vehicle operating states. Detailed description of the figures

The illustration according to FIG. 1 shows an electromechanical drive arrangement with an electromechanical main drive motor E, which comprises a rotor ER and a stator ES, a reduction gear device G, which comprises a transmission input GE, a transmission output GA, at least one reduction stage GR and a transmission housing GH, which houses the reduction stage GR, an axle differential gear AD, for branching the drive power at the output of the reduction gear device G to a first and a second wheel drive train section DL, DR, and an auxiliary unit AUX1 which can be driven via the main drive motor E. The auxiliary unit AUX1 can in particular be an air conditioning compressor, a power steering pump or a cooling water pump for cooling a battery module and for heating the vehicle interior of a corresponding motor vehicle.

The drive arrangement according to the invention is characterized in that the auxiliary unit gat AUX1 is at least partially integrated in the gear housing GH, in the gear housing GH a first switching element SE1 and a second switching element SE2 are bound, the first switching element SE1 being designed in this way and in the drives is integrated that the drive connection between the rotor ER and the axle differential AD is switchable closable and separable and the second switching element SE2 is designed in such a way that the auxiliary unit AUX1 can be driven selectively via the rotor ER according to the switching state thereof Drive connection between the rotor ER and the axle differential gear AD is canceled.

In the drive arrangement according to the invention, the auxiliary unit AUX1 has an input shaft E1 and this input shaft E1 is arranged coaxially with the rotational axis X of the rotor ER of the electric motor E.

The first switching element SE1 is designed such that a drive connection to the axle differential gear AD can be produced via this. In this exemplary embodiment, the first switching element SE1 is arranged upstream of the reduction stage GR, but there is a passage of the rotor shaft to the second switching element SE2 (not shown). The reduction stage GR is designed here as a spur gear stage and the first switching element SE1 enables a first spur gear G1, which is small in diameter, to be coupled to the rotor shaft RS. For this purpose, the first switching element SE1 is designed as a form or friction conclusively coupling switching element. The actuators provided for setting the respective switching state of the first and the second switching element SE1, SE2 are not shown further here, they can be integrated into the respective switching element SE1, SE2 and in particular be designed as electromagnetic or fluid mechanical actuators.

The electric motor E, the reduction gear GR and the auxiliary unit AUX are integrated in a common housing device GH, the axle differential gear AD is connected to this housing device GH or also integrated into it.

In the drive arrangement according to the invention, the transmission G is connected on the input side to at least one electric drive motor E and on the output side to at least one vehicle axis DL, DR. The gearbox G comprises one or more shafts in which a planetary gear set can be integrated or which are connected to one another by spur gear stages or planetary gear sets. On the rotor shaft RS of the drive motor E, which leads to the gearbox G, the auxiliary unit AUX1, such as e.g. an air conditioning compressor, a water pump or similar tethered.

The illustration according to FIG. 2 again shows an electromechanical drive arrangement with an electromechanical main drive motor E which comprises a rotor ER and a stator ES, a reduction gear device G which comprises a transmission input GE, a transmission output GA, at least one reduction stage GR and a transmission housing GH, which houses the reduction stage GR, an axle differential gear AD, for branching the drive power present at the output of the reduction gear device to a first and a second wheel drive train section DL, DR, and an auxiliary unit AUX1 which can be driven via the main drive motor E. This drive arrangement according to the invention is also characterized in that the auxiliary unit AUX1 is fully or at least partially integrated into the transmission housing GH, in the transmission housing GH a first switching element SE1 and a second switching element SE2 are provided, the first switching element SE1 being designed and constructed in this way is integrated in the drive arrangement that the drive connection between the rotor ER and the axle differential AD can be switched, closed and disconnected, and the second switching element SE2 is designed such that the auxiliary unit AUX1 can be driven via the rotor ER according to its coupling state, especially when the drive connection between the rotor ER and the axle differential AD is canceled. In this variant, the auxiliary unit AUX1 is integrated into the drive arrangement in such a way that the input shaft E1 of the auxiliary unit AUX1 is arranged coaxially with the rotor axis X. The first switching element SE1 is integrated in the reduction stage GR, in particular the first spur gear G1 thereof. This first spur gear G1 engages radially from the outside in a second spur gear G2 of the reduction stage GR. This second spur gear G2 forms the large or ring gear of the axle differential gear AD and is torsionally connected to the revolving housing UH or the web of the axle differential gear AD. The second switching element sits in an intermediate area between the first spur gear G1 and the auxiliary unit AUX1.

The illustration according to FIG. 3 shows a third variant of an electromechanical drive arrangement according to the invention with an electromechanical main drive motor E which comprises a rotor ER and a stator ES, a reduction gear device G which has a transmission input GE, a transmission output GA, at least one reduction stage GR and a Gearbox housing GH, which houses the reduction stage, an axle differential gear AD, for branching the drive power present at the output of the reduction gear device to a first and a second wheel drive train section DL, DR, and a first auxiliary unit AUX1 which can be driven by the main drive motor E and in which Gearbox housing GH is included.

In this variant, the auxiliary unit AUX1 is integrated into the drive arrangement in the interior of the transmission housing such that the input shaft E1 of the auxiliary unit AUX1 is arranged offset parallel to the rotor axis X. This is achieved here by a traction mechanism drive TM. This comprises a first traction wheel TM1 and a second traction wheel TM2 and a traction device TM3 designed as a belt or chain. The first traction wheel TM1 is arranged coaxially with the rotor axis X and can be coupled to the rotor shaft or the first spur gear G1 of the reduction stage via the second switching element SE2.

The first switching element SE1 is integrated in the reduction stage GR, in particular the first spur gear G1 thereof. This first spur gear G1 engages radially from the outside in a second spur gear G2 of the reduction stage RG. The second spur gear G2 forms the large or ring gear of the axle differential gear AD and is connected torsion-proof to the revolving housing UH or web of the axle differential gear AD.

The illustration according to FIG. 4 shows a fourth variant of an electromechanical drive arrangement according to the invention with an electromechanical main drive motor E, which NEN ER rotor and a stator ES, a reduction gear device G, which includes a gear input GE, a gear output GA, at least one reduction stage GR and a gear housing GH, which houses the reduction stage, an axle differential gear AD, for branching the at the output of the reduction gear device applied drive power to a first and a second wheel drive train section DL, DR, and a first auxiliary unit AUX1 and a second auxiliary unit AUX2, both of which can be driven via the main drive motor E.

This drive arrangement according to the invention is characterized in that both auxiliary units AUX1, AUX2 are fully or at least partially integrated into the gear housing GH and a first switching element SE1 and a second switching element SE2 are provided in the gear housing GH, the first switching element SE1 being designed and is integrated in the drive arrangement that the drive connection between the rotor ER and the axle differential gear AD is switchably closable and separable, and the second switching element SE2 is designed such that the auxiliary units AUX1, AUX2 via the switch according to its switching or coupling state Ro tor ER are drivable when the drive connection between the rotor ER and the axle differential gear AD is canceled via the first switching element SE1.

In this variant, the auxiliary unit AUX1 has an input shaft E1 and this input shaft E1 is arranged coaxially with the circumferential axis X of the rotor ER of the electric motor E. The auxiliary unit AUX2 is integrated into the drive arrangement such that the input shaft E2 of the auxiliary unit AUX2 is offset parallel to the rotor axis X. This is again achieved by a traction mechanism drive TM. This comprises a first traction wheel TM1 and a second traction wheel TM2 and a traction device TM3 designed as a belt or chain. The first traction wheel TM1 is arranged coaxially with the rotor axis X and can be coupled to the rotor shaft or the first spur gear G1 of the reduction stage via the second switching element SE2.

The illustration according to FIG. 5 shows an electromechanical drive arrangement with an electromechanical main drive motor E, which comprises a rotor ER and a stator ES, a reduction gear device G, which comprises a transmission input GE, a transmission output GA, at least one reduction stage GR and a transmission housing GH, which houses the reduction stage, an axle differential gear AD, for branching the drive power present at the output of the reduction gear device to a first one and a second wheel drive train section DL, DR, and an auxiliary unit AUX1 which can be driven via the main drive motor E.

This drive arrangement according to the invention is also distinguished by the fact that the auxiliary unit AUX1 is fully or at least partially integrated in the gear housing GH, in the gear housing GH a first switching element SE1 and a second switching element SE2 are provided, the first switching element SE1 being designed in this way and in the drive arrangement is integrated so that via this the drive connection between the rotor ER and the axle differential AD is switchable closable and separable and then via the second switching element SE2 the auxiliary unit AUX1 can be driven selectively and if necessary via the rotor ER if the drive connection between the Ro tor ER and the axle differential gear AD is lifted.

In this variant, the auxiliary unit AUX1 is integrated into the drive arrangement in such a way that the input shaft E1 of the auxiliary unit AUX1 is arranged parallel to the rotor axis X. This is achieved here by a traction mechanism drive TM. This comprises a first traction wheel TM1 and a second traction wheel TM2 and a traction device TM3 designed as a belt or chain. The first traction wheel TM1 is arranged coaxially with the rotor axis X and also houses the second switching element SE2 via which the first traction wheel TM1 can be coupled to the rotor shaft or.

The first spur gear G1 of the reduction stage RG can be connected to the rotor shaft RS via the first switching element SE1. This first spur gear G1 engages radially from the outside in a second spur gear G2 of the reduction stage RG. This second spur gear G2 forms the large or ring gear of the axle differential gear AD and is torsionally connected to the Umlaufge housing UH of the axle differential gear AD.

As illustrated in particular in connection with FIGS. 3 and 4, it is possible to connect the auxiliary unit AUX1 or both auxiliary units AUX1, AUX2 via a belt or chain drive, one of the drive wheels TM1, TM2 (here TM1) or one of the Drive pulleys are coaxially connected and the traction drive TM is arranged axially parallel to the electric motor shaft. The chain or belt drives can be equipped in a geous manner with conventional guide and / or tensioning rails or deflection and / or tensioning rollers. The connection of the assembly AUX1 to the motor shaft RS by incorporating the second switching element SE2 has the advantage that the torque transmission from the electric motor to the assembly AUX1 takes place over a short distance and so on Losses are reduced. The electric motor E or the "E-machine" as well as the auxiliary unit AUX1 or the auxiliary units AUX1, AUX2 are integrated in the gearbox housing GH, which enables a space-saving design and avoids additional sealing of the shafts.

In the exemplary embodiments according to FIGS. 1 and 3, the auxiliary unit AUX1 is detachably connected coaxially to the motor shaft coaxially via the second switching element SE2. The second switching element SE2 can be active, e.g. as magnetic coupling, as well as passive, e.g. Freewheel, be connectable or detachable. At the same time, this second switching element SE2 enables the decoupling of the electric motor and the unit, independently of one another or simultaneously, from the transmission and thus from the drive train of the vehicle. This function integration reduces the number of components to a minimum.

The first and / or the second switching element SE1, SE2 can contain constant or variable step-up / step-down stages, e.g. a planetary gear set. The respective switching element SE1, SE2 can simultaneously have a damping or decoupling effect on the drive train and / or units, e.g. using a spring-damper element similar to a two mass flywheel. The switching element SE1 can e.g. also be integrated into the interior of a gear wheel of the GR gear stage.

The illustration in FIG. 6 illustrates the mode of operation of the drive arrangement according to the invention in conjunction with selected vehicle operating states. Three coupling functions are possible here. The coupling function S1 leads to a connection of the rotor with the axle differential. The coupling function S2 leads to a connection of the auxiliary unit AUX1 to the rotor. The coupling function S3 leads to a connection of the axle differential with the auxiliary unit.

The arrangement can be implemented in such a way that the coupling functions S1 and S2 are provided via the first switching element SE1 and the coupling function S3 is provided via the second switching element. This is illustrated in the concept sketch K1. As an alternative to this, the arrangement can also be implemented such that only the coupling function S1 is provided via the first switching element SE and the coupling functions S2 and S3 are implemented by the second switching element S2. This approach is illustrated in sketch K2.

In principle, the coupling function S3 can also be provided by a freewheel, since the drive of the auxiliary unit via the axle differential gear only makes sense when the vehicle is in overrun mode. The two switching elements SE1, SE2 are designed so that these three coupling functions can be provided. The first coupling function S1 enables a power transfer from the electric motor E to the axle differential AD, as stated above. The second coupling function enables power to be transferred from the electric motor E to the auxiliary unit AUX1. The third coupling function enables power transfer from the axle differential AD to the auxiliary unit AUX1. The coupling functions S1, S2, S3 of the switching elements SE1, SE2 are illustrated in accordance with the different operating states via tables T 1 and T2.

In the operating state 1 shown in table T 1, the electric motor E is active and the first switching element SE1 provides the coupling function S1, according to which the torque of the rotor shaft is guided to the axle differential via the reduction gear stage GR. If the auxiliary unit AUX1 is to be active in this state, the coupling functions S2 and S3 are also provided.

When the vehicle is coasting in accordance with operating state 2 in table T1 and the thrust is excess, the coupling function S1 and the coupling function S3 are activated. Now it is followed by a power conversion in the recuperation operating mode via the electric motor E and also a mechanical drive of the auxiliary unit AUX1 directly by tapping power from the axle differential AD.

In the so-called sailing mode, that is, the vehicle continues to run smoothly without a significant braking effect in accordance with operating state 3 in table T1, the coupling functions S1, S2 are canceled and only the coupling function S3 is activated. Now the auxiliary unit AUX1 is driven directly by the axle differential AD without electrical power.

When the vehicle is stationary according to operating state 4 in table T1, the coupling functions S1 and S3 are deactivated and the auxiliary unit is activated via the coupling function

52 driven directly by the electric motor E.

When the vehicle is at a standstill without the AUX1 auxiliary unit needing action, e.g. when parking. The electric motor E is switched off. In this state, the switching elements SE1, SE2 can assume any state, since in this state no specific coupling function is required per se. However, it is also possible to use the coupling functions S1 and

53 to activate a slightly increased holding torque, a braking effect in the event of unintentional rolling and possibly an active braking effect by actuating the electric motor. The coupling functions S1, S2 can be accomplished via a form-locking coupling element or correspondingly activatable clutches. The coupling function S3 can also be accomplished by a freewheel and thus automatically result in overrun of the vehicle.

In the drive arrangement according to the invention for a purely electrically powered vehicle, an electric main drive motor is provided. This is connected to or integrated in a gear unit. About the gear device, a driving axle is preferably driven via an axle differential gear. The gear unit consists of one or more shafts in which a planetary gear set can be integrated or which are connected with spur gear stages or planetary gear sets. On the shaft of the drive motor, which leads to the gearbox, an auxiliary unit, e.g. Air conditioning compressor, water pump or similar tied up (fig. 1). But it is also a connection e.g. possible by means of a belt or chain drive, one of the drive wheels or one of the drive pulleys being connected coaxially and the traction mechanism drive being arranged axially parallel to the electric motor shaft (FIGS. 3 and 5). If necessary, the chain or belt drives can be equipped with conventional guide and / or tensioning rails or deflection and / or tensioning rollers. The connection of the auxiliary unit to the motor shaft has the advantage that the torque transmission from the electric motor to the unit takes place over a short distance, thereby reducing losses.

The electric machine and auxiliary unit (s) are integrated in the gear housing, which enables a space-saving design and avoids additional shaft seals. Both the auxiliary unit and the electric motor are each coaxially connected to the transmission input shaft via a switching element. It is also possible to release or establish the connection between the engine and the auxiliary unit via one of the two switching elements, regardless of the coupling state to the transmission input shaft. The switching elements can be active, e.g. Magnetic coupling, as well as passive, e.g. Freewheel, be connectable or detachable.

The switching elements can contain constant or variable gear ratios, such as a planetary gear set. The switching elements can simultaneously have a damping or decoupling effect on the drive train and / or units, for example by means of a spring-damper element similar to an DMF. Both switching elements can, for example, also in one Gear of a gear stage to be integrated (Figure 2) The switching states of the elements accordingly the different operating states are in Figure 6 for an example he explained. The coaxially connected auxiliary unit can also be connected to further auxiliary units, for example by means of a chain or toothed belt drive (FIG. 4). All connected auxiliary units can have an additional coupling and / or damping and / or decoupling element on their drive shaft. This enables individual operation of each individual unit depending on the operating state of the vehicle and on the other elements. At the same time, the unit can be decoupled from torsional vibrations of the drive train, which ensures more even and efficient operation and / or avoids possible negative effects of the connection process on the drive train and thus indirectly on the vehicle.

Claims

claims

1. Electromechanical drive arrangement with:

an electromechanical main drive motor (E) which comprises a rotor (ER) and a stator (ES),

- A reduction gear device (G), which includes a transmission input (GE), a transmission output (GA), at least one reduction stage (GR) and a transmission housing (GH), which houses the reduction stage (GR),

- An axle differential gear (AD) for branching the drive power (GR) at the output of the reduction gear (GR) to a first and a second wheel drive train section (DL, DR) and

- An auxiliary unit (AUX1) which can be driven via the main drive motor (E), wherein

- The auxiliary unit (AUX1) is fully or at least partially integrated in the gearbox (GH),

- A first switching element (SE1) and a second switching element (SE2) are provided in the transmission housing (GH),

- The first switching element (SE1) is formed and is integrated into the drive arrangement, so that the drive connection between the rotor (ER) and the axle differential (AD) is switchably closable and separable,

- The first or the second switching element (SE1, SE2) are designed in such a way that a drive connection between the auxiliary unit (AUX1) and the rotor (ER) can be established via the se, and

- The auxiliary unit (AUX1) can be driven via the axle differential (AD) when the drive connection between the rotor (ER) and the axle differential (AD) is canceled via the first switching element (SE1).

2. Drive arrangement according to claim 1, characterized in that the auxiliary unit (AUX1) has an input shaft (E1) and this input shaft (E1) to the rotational axis (X) of the rotor (ER) of the electric motor (E) is arranged offset in parallel.

3. Drive arrangement according to claim 1, characterized in that the auxiliary unit (AUX1) has an input shaft (E1) and this input shaft (E1) to the rotational axis (X) of the rotor (ER) of the electric motor (E) is arranged coaxially.

4. Drive arrangement according to at least one of claims 1 to 3, characterized in that the drive arrangement comprises two auxiliary units (AUX1, AUX2) and here egg nes of the auxiliary units (AUX1) with its input shaft (E1) to the circumferential axis (X) of the rotor (ER) coaxially and the second auxiliary unit (AUX2) is offset parallel to this circumferential axis (X).

5. Drive arrangement according to at least one of claims 1 to 4, characterized in that the first switching element (SE1) between the electric motor (E) and the reduction stage (GR) is arranged.

6. Drive arrangement according to at least one of claims 1 to 5, characterized in that the first switching element (SE1) is integrated in the reduction stage (GR).

7. Drive arrangement according to at least one of claims 1 to 5, characterized in that the reduction stage (RG) is designed as a spur gear stage.

8. Drive arrangement according to at least one of claims 1 to 7, characterized in that the auxiliary unit (AUX1, AUX2) via a ver in the transmission housing (GH) running belt drive is driven.

9. Drive arrangement according to at least one of claims 1 to 8, characterized in that the drive arrangement comprises a freewheel device and that this freewheel device allows that in overrun mode of the vehicle, the input shaft (E1) of the Ne benaggregats (AUX1) by the from Axle differential gear (AD) tapped energy is driven and overhauled the rotor shaft (RS) (coupling function S3).

10. Drive arrangement according to at least one of claims 1 to 9, characterized in that the first switching element (SE1) and / or the second switching element (SE2) are each designed as a positive or frictionally coupling switching element.