DE102019206967A1 - Drive axle for an electrically powered vehicle - Google Patents

Abstract

The invention relates to a drive axle for an electrically drivable vehicle with two drive wheels (R1, R2) and a common wheel axle (a), comprising two electrical machines (EM1, EM2), two two-speed gearboxes (G1, G1a, G2, G2a), an axle differential (DI) between the drive wheels (R1, R2), the first electric machine (EM1) and the first two-speed gearbox (G1) having a first drive train (A1) and the second electric machine (EM2) and the second two-speed Manual transmission (G2) form a second drive train (A2), with both drive trains (A1, A2) driving into the axle differential (DI) and with the first and second two-speed manual transmission (G1, G2) each having a shiftable first planetary set (PS1) each with a spider shaft (ST1), a sun shaft (SO1) and a ring gear shaft (HR1).

Description

The invention relates to a drive axle for an electrically drivable vehicle with two drive wheels and a common wheel axle, comprising two electrical machines, two two-speed manual transmissions, an axle differential between the drive wheels, the first electric machine and the first two-speed manual transmission having a first drive train and the The second electric machine and the second two-speed manual transmission form a second drive train and both drive trains drive into the axle differential.

Through the EP 2 450 597 A1 an electric drive for a vehicle with two electric machines and two partial transmissions, which drive a common output shaft, became known. The partial transmissions are designed as spur gears with switchable spur gear stages. There is an axial offset between the common output shaft and the drive axles of the electrical machines, which is caused by the center distances of the spur gear stages. The known electric drive can be shifted under load when a special shifting strategy is used, ie a gear change takes place without interruption of the tractive effort.

One object of the invention is to provide the drive components in an electrically drivable vehicle of the type mentioned above, i.e. H. to arrange the electrical machines and the gearbox in the area of the drive axle to save space and weight.

The invention comprises the features of patent claim 1. Advantageous embodiments result from the subclaims.

According to the invention, two drive trains, each comprising an electric machine and a two-speed manual transmission, and an axle differential between the drive wheels are provided for a drive axle for an electrically drivable vehicle, both drive trains driving into the axle differential, from which the power is distributed to the drive wheels becomes. Each two-speed manual transmission has a shiftable first planetary gear set to which two shift elements for shifting a first and a second gear are assigned. The switching elements are preferably designed as unsynchronized claw switching elements. The advantage of the drive according to the invention is that the gears can be shifted without interrupting the traction. The gear change is preferably not carried out simultaneously in both drive trains, but rather offset in time. If the first drive train is shifted, the first electric machine synchronizes when changing gears, and the second electric machine of the second drive train provides support by driving it into the axle differential, from where the power is distributed to both drive wheels. The two-speed gearbox reduces the speed of the electrical machines, also known as electric machines for short, in stages, so that an increased tractive force on the drive wheels and a larger speed range for the electric vehicle are achieved.

According to a preferred embodiment, the switchable first planetary set is driven via its ring gear shaft, the drive preferably taking place via the electrical machine. This means that the other two shafts are available as shift shafts and as coupling or output shafts.

According to a further preferred embodiment, each two-speed manual transmission, hereinafter also referred to as manual transmission for short, has a second planetary set which is not shiftable but is designed as a constant transmission stage. The first planetary set thus forms the actual two-speed manual transmission.

According to a further preferred embodiment, the first planetary gear set is coupled to the sun shaft of the second planetary gear set via its spider shaft. The power of the first planetary gear set, which is driven by the electric machine, thus flows via the coupling shaft into the second planetary gear set, whose ring gear shaft is held and whose spider shaft forms the output shaft. The spider shafts of the two second planetary sets of the first and the second drive train are connected to one another and jointly drive into the axle differential, i. H. they are firmly connected to the differential cage, also known as the differential housing. The power of both drive trains is thus brought together in the axle differential and from there distributed to the drive wheels via the differential output shafts. As long as one of the two electric motors is running, there is also a torque on both drive wheels, i.e. H. in this case there is no interruption of the traction.

According to a further preferred embodiment, the two second planetary sets are arranged in the area of the central plane in such a way that the axle differential is arranged radially within the two second planetary sets, in particular radially within their sun shafts. This results in a gain in installation space in the axial direction, i. H. achieved in the direction of the wheel axis.

According to a further preferred embodiment, the two-speed gearboxes each have second planetary sets which are driven by the electrical machines via their sun shafts. In this variant of the two-speed manual transmission, the sequence in the power flow is from first planetary gear set and the second planetary gear set interchanged, ie the second planetary gear set, which is designed as a constant transmission stage, is driven by the electric machine and transmits its power to the switchable first planetary gear set via a coupling shaft. The coupling shaft is formed by the spider shaft of the first and the ring gear shaft of the second planetary set. The ring gear shaft of the second planetary set is held in place. The advantage of this arrangement, in which the first planetary gear sets with their shifting elements are “inside”, ie in the area of the axle differential and the center plane, is that the shifting elements and their associated actuators are easily accessible between the two electric machines. Both actuators can preferably be arranged in a common radial plane, that is to say perpendicular to the wheel axis, which results in a gain in axial installation space.

According to a further preferred embodiment, the output of the first two planetary gear sets of the first and second drive trains takes place via their spider shafts, which are firmly connected to the differential cage.

According to a further preferred embodiment, the first gear is engaged by closing the first shift element, whereby the sun shaft of the first planetary gear set is coupled to the housing, d. H. is fixed. This results in the translation of the first planetary gear set from the ratio of the speeds of the two rotating shafts, i.e. H. the ring gear shaft and the spider shaft. The ratios of the first and second planetary gear sets, multiplied together, result in the ratio for the first gear.

According to a further preferred embodiment, the second gear is formed by closing the second shift element, whereby the first planetary gear set is blocked by coupling two of the three shafts with one another. The sun shaft is preferably coupled or blocked with the web shaft. The first planetary set then runs as a block with a ratio of 1: 1. The constant ratio of the second planetary gear set thus determines the ratio of the second gear.

According to a further preferred embodiment, the two drive trains, which each consist of an electrical machine and a two-speed manual transmission, are constructed and arranged mirror-symmetrically with respect to a central plane which runs perpendicular to the wheel axis. The two-speed manual transmissions therefore also have the same gear ratios in first and second gear. In addition, the electric machines and the planetary gear sets of the gearbox are arranged coaxially to the wheel axis, which is also the axis of rotation of the electric machines. This has the advantage that all drive components are arranged compactly around the wheel axle and that the space available between the drive wheels and in the area of the wheel axle is used to the greatest possible extent.

According to a further preferred embodiment, the axle differential can be locked, with a switching element which is arranged in the center and outside of the differential housing and is preferably designed as a claw coupling which connects one of the two differential output shafts to the differential housing. This creates a rigid connection between the two drive wheels, which is particularly advantageous when off-road and when there are different surfaces on the right and left.

According to a further preferred embodiment, the gearbox has a shiftable first and a second planetary gear set, wherein the first planetary gear set can be driven by the electric machine in first gear via its ring gear shaft and in second gear via its spider shaft. This variant of the first planetary set with a switchable drive is also referred to as a clutch variant.

According to a further preferred embodiment, the spider shaft of the first planetary set is firmly connected to the sun shaft of the second planetary set and thus forms the coupling shaft between the two planetary sets, which is driven by the electric machine in second gear.

According to a further preferred embodiment, the sun shafts of the first and the ring gear shafts of the second planetary gear sets are jointly supported on the housing. Thus, one shaft is held in each case for both planetary sets.

According to a further preferred embodiment, the second planetary gear sets are arranged behind the axle differential, viewed in the direction of force flow, and are thus driven by the differential output shafts. The gearboxes of the first and the second drive train thus only have one planetary gear set, namely the switchable first planetary gear set, which drives into the axle differential via its spider shaft, i. H. the spider shaft is firmly connected to the differential cage. The advantage of this arrangement is that the axle differential is subject to less load and can therefore be dimensioned smaller, which also applies to the differential output shafts, which are subjected to a lower torque.

According to a further preferred embodiment, the first switching element - on the right and left side - supported on the housing, the support points being arranged directly in the area of the electric machines, in particular radially within the rotors. This has the advantage that the housing in the area of the support can serve as the basis for mounting the electric machine.

According to a further preferred embodiment, seen in the direction of force flow, further constant gear ratios are arranged behind the axle differential and in the area close to the wheel, which bring about a further reduction in the speed of the electric machines. The other constant gear ratios can be designed as coaxial planetary sets, which can preferably be integrated into the wheel hubs of the drive wheels.

According to a further preferred embodiment, the further constant transmission stages can be designed as so-called portal stages, which results in an axial offset between the axis of rotation of the electric machines and the wheel axis. This has the advantage of increased ground clearance, combined with the possibility of using electric machines with a larger diameter.

According to a further preferred embodiment, the portal step has a web with planetary gears, a sun gear and a ring gear, the web being fixed and the output of the stationary gear being carried out via the ring gear on the drive wheel. As a result of the planetary gears, of which at least two are arranged on the circumference, there is a power distribution from the drive to the driven side.

According to a further preferred embodiment, the portal stage is designed as a spur gear with a drive gear, two intermediate gears and a driven gear, the intermediate gears being in meshing engagement with both the drive gear and the driven gear. The intermediate gears increase the center distance on the one hand and split the power flow from the drive to the output on the other.

According to a further preferred embodiment, the electric machines have rotors with a cylindrical cavity, which is used as installation space for the arrangement of the planetary gear sets, the shifting elements and / or the axle differential. This results in a compact design; in particular, the arrangement of the planetary sets radially inside the rotors saves installation space in the axial direction.

• 1 eine Antriebsachse eines Elektrofahrzeuges mit zwei E-Maschinen, zwei Zweigang-Schaltgetrieben und einem Achsdifferenzial zwischen den Antriebsrädern (Darstellung teilweise),
• 2 die Zweigang-Schaltgetriebe mit einer Verblockungsvariante des ersten Planetensatzes,
• 3 die Zweigang-Schaltgetriebe mit zweiten Planetensätzen, die radial außerhalb vom Achsdifferenzial angeordnet sind.
• 4 eine Antriebsachse mit sperrbarem Achsdifferenzial und Schaltelement zur Sperrung,
• 5 eine Antriebsachse mit Schaltgetrieben, bei welchen die Planetensätze vertauscht sind (vollständige Darstellung),
• 6 Schaltgetriebe mit einer Kupplungsvariante des ersten Planetensatzes (umschaltbarer Antrieb),
• 7 eine Antriebsachse, bei welcher der zweite Planetensatz in Kraftflussrichtung hinter dem Achsdifferenzial angeordnet ist,
• 8 Gehäuseabstützung eines Schaltelements im Bereich der E-Maschine,
• 9 eine Antriebsachse als Portalachse mit Portalstufen (erste Ausführung) und
• 10 eine Antriebsachse als Portalachse mit Portalstufen (zweite Ausführung).

Exemplary embodiments of the invention are shown in the drawing and are described in more detail below, it being possible for further features and / or advantages to emerge from the description and / or the drawing. Show it

• 1 a drive axle of an electric vehicle with two electric motors, two two-speed manual transmissions and an axle differential between the drive wheels (partial representation),
• 2 the two-speed gearbox with a locking variant of the first planetary gear set,
• 3 the two-speed manual transmission with second planetary gear sets, which are arranged radially outside of the axle differential.
• 4th a drive axle with lockable axle differential and switching element for locking,
• 5 a drive axle with gearboxes in which the planetary gear sets are interchanged (complete illustration),
• 6th Manual transmission with a clutch variant of the first planetary set (switchable drive),
• 7th a drive axle in which the second planetary gear set is arranged behind the axle differential in the direction of force flow,
• 8th Housing support of a switching element in the area of the electric machine,
• 9 a drive axis as a portal axis with portal steps (first version) and
• 10 a drive axis as a portal axis with portal steps (second version).

1 shows a drive axle 1 for an electrically powered vehicle, hereinafter also referred to as an electric vehicle. The drive axle 1 includes two drive wheels R1 , R2 which are on a common wheel axle a are arranged. Symmetrical to a median and symmetry plane M. which is perpendicular to the wheel axis a are two drive trains A1 , A2 arranged, the first drive train A1 a first electric machine EM1 with a first rotor RO1 as well as a first two-speed manual transmission G1 and the second drive train A2 a second electrical machine EM2 with a second rotor RO2 as well as a second two-speed manual transmission G2 include. The first two-speed manual transmission G1 , hereinafter also referred to as the first manual transmission G1 called, includes a switchable first planetary gear set PS1 as well as a non-switchable second planetary set PS2 , which one with the first planetary set PS1 is coupled and designed as a constant gear ratio. Both planetary sets PS1 , PS2 as well as the electrical machines EM1 , EM2 are coaxial with the wheel axle a arranged and only half, ie half above the wheel axle a shown; the lower half, not shown, is mirror-symmetrical to the wheel and axis of rotation a educated. The first planetary set PS1 has a web wave ST1 , a sun wave SO1 and a ring gear shaft HR1 on which stuck to the rotor RO1 the first electric machine EM1 connected is. The first planetary set PS1 are two switching elements A. , B. assigned, which can also assume two switching positions, also designated with A, B. The second planetary set PS2 has a web wave ST2 , a sun wave SO2 and a ring gear shaft HR2 on, which is supported on the housing side, ie held in place. Housing is generally to be understood as the transmission housing, which is represented in the drawing by hatching without a reference number. The first planetary set PS1 is about its web wave ST1 and the sun wave SO2 of the second planetary gear set PS2 with the second planetary set PS2 coupled, ie firmly connected. Coaxial to the wheel axle a is in the middle between the drive wheels R1 , R2 an axle differential DI with a differential basket DIK , also differential housing DIK called, arranged. The axle differential DI is preferably a bevel gear differential DI as shown, but can also be designed as a spur gear differential.

The second drive train A2 is - based on the central plane M. - mirror image of the first drive train A1 formed, ie it also has a first switchable planetary gear set PS1 with switching elements D. , C. and a second planetary set coupled to the first PS2 on. The first two planetary sets PS1 are about their ring gear shafts HR1 from the e-machines EM1 , EM2 driven. The web waves ST2 of the two second planetary sets PS2 drive together in the axle differential DI one, ie the web waves ST2 are fixed to the differential basket DIK connected. The axle differential DI has two differential output shafts 3a , 3b which each have a further constant gear ratio PS3 drive. The constant transmission stage is the third planetary gear set PS3 with a sun wave SO3 , a web wave ST3 and a fixed ring gear shaft HR3 educated. The drive of the third planetary set PS3 takes place via the sun wave SO3 , the output via the spider shaft ST3 , which with the output shaft 2a for the first drive wheel R1 or with the output shaft 2 B for the second drive wheel R2 connected is. The third planetary set PS3 is arranged close to the wheel and can optionally be placed in the wheel hub of a drive wheel R1 , R2 to get integrated.

The switching elements A. , B. , C. , D. are preferably designed as unsynchronized claw switching elements. With the first manual transmission G1 and the second manual transmission G2 two gears, a first and a second gear, can be shifted. This results in a two-stage reduction in the speed of the electric machines EM1 , EM2 reached. In order to avoid an interruption of the pulling force when changing gears, the shifts or gear changes on the right and left side should be offset in time. The shift element is used to engage first gear A. closed, causing the sun wave SO1 of the first planetary gear set PS1 is coupled to the housing, that is, held. The gear ratio of the first planetary set PS1 then results from the ratio of the speed of the ring gear shaft HR1 which from the first rotor RO1 is driven, and the speed of the spider shaft ST1 . The shift element is used to engage second gear B. closed, making the web shaft ST1 and the sun wave SO1 of the first planetary gear set PS1 are coupled to one another, ie the first planetary gear set PS1 is "blocked" and circulates as a block with a ratio of 1: 1. Basically, there are always three variants when a planetary set is blocked, ie two of the three rotating shafts are coupled to one another. Between the two switch positions A. , B. , ie if none of the switching elements A. , B. is closed, there is a neutral position in which one or both electrical machines EM1 , EM2 are disconnected. This enables what is known as sailing operation, that is, the electric vehicle can roll freely without the drag of the rotating rotor.

If, for example, the second gear is to be engaged, this is initially only done on one side, for example on the left side in the first gearbox G1 , which from the first electric machine EM1 is driven. During the shifting process, ie between disengaging the first gear and engaging the second gear, an interruption in tractive force occurs, ie the left or first electric machine EM1 no longer drifts into the differential DI one. On the other hand, the right or second electric machine is driving EM2 , because in the second manual transmission G2 no gear change takes place in the differential DI one, which the drive power over the two differential output shafts 3a , 3b on the two drive wheels R1 , R2 distributed. The right electric machine EM2 So “supports” when switching to the left. This results in an interruption of the tractive force on the drive wheels R1 , R2 avoided. During the shift in the first manual transmission G1 synchronizes the first electric machine EM1 the switching process. In this respect, the disadvantage of the unsynchronized claw shifting elements is compensated for by this synchronization.

2 shows a drive axle as a further embodiment of the invention 2 , where the same reference numerals as in 1 be used. In contrast to the previous embodiment, in 2 a Blocking variant of the first planetary gear set PS1 shown. By closing the switching element B. (on the left) or by closing the switching element D. (on the right) becomes the sun wave SO1 with the ring gear shaft HR1 coupled to the first planetary gear set, ie the first planetary gear set PS1 is blocked and circulates as a block. With the lock, the second gear is shifted. The transmission of the second gear is thus solely through the constant transmission of the second planetary gear set PS2 which is the first planetary set PS1 is downstream, determined.

3 shows a drive axle as a further embodiment of the invention 3 , the same reference numerals being used as before for the same parts. The arrangement of the second planetary gear sets differs here from the two previous exemplary embodiments PS2 in relation to the axle differential DI . The two second planetary sets PS2 are in the direction of the wheel axis a seen, close to each other, symmetrical to the median plane M. and radially outside the differential DI arranged. In other words: the differential DI is radially inside the two second planetary gear sets PS2 , especially their sun waves SO2 arranged. This arrangement saves installation space in the axial direction.

4th shows a drive axle as a further embodiment of the invention 4th , in which the same reference numerals as before are used for the same parts. What differs from the previous exemplary embodiments is that the differential DI is lockable, by means of a switching element E. , which is preferably designed as a claw coupling. The switching element E. connects the differential cage when closed DIK , ie the housing of the axle differential DI with one of the two differential output shafts 3a , 3b - In the illustrated embodiment with the right differential output shaft 3b . This is between the two drive wheels R1 , R2 a rigid connection established. The switching element E. is preferably in the middle, ie in the area of the central plane M. and outside the differential basket DIK arranged. It is advantageous here that the installation space between the two second planetary gear sets arranged next to one another PS2 is being used. An actuator, not shown, for actuating the switching element E. can also be arranged in the middle of the housing.

5 shows a drive axle as a further embodiment of the invention 5 in a complete representation, the same reference numerals being used as before for the same parts. Different from the previous exemplary embodiments, in particular the design according to FIG 1 are at the drive axle 5 the manual transmission G1a , G2a , in which the sequence in the power flow from the first planetary set PS1 and from the second planetary set PS2 was swapped, with the first planetary set PS1 is also switchable and the second planetary gear set PS2 also forms a constant translation level. The second planetary set PS2 is driven by a drive shaft 1a the first electric machine EM1 or from a drive shaft 1b the second electric machine EM2 about his sun wave SO2 driven while its ring gear shaft HR2 is supported on the housing side. The second planetary set PS2 is about its web wave ST2 and the ring gear shaft HR1 of the first planetary set PS1 coupled with this, ie firmly connected. The web wave ST2 and the ring gear shaft HR1 thus form the coupling shaft between the two planetary gear sets PS1 , PS2 . The first planetary set PS1 on the left are the switching elements A. , B. and the first planetary gear set PS1 on the right side are the switching elements C. , D. assigned. The gears are shifted as in the previous exemplary embodiments: By closing the shift element A. first gear is engaged and the sun wave SO1 of the first planetary gear set PS1 connected to the housing. By closing the switching element B. the second gear is engaged and the first planetary gear set PS1 blocked by its sun wave SO1 with its web wave ST1 is coupled. Here, too, two further blocking variants are possible. The output takes place via the spider shaft ST1 , which with the differential basket DIK of the axle differential DI is firmly connected. The switching elements A. , B. are via a first actuator AK1 actuated the switching elements C. , D. are via a second actuator AK2 actuated. Both actuators AK1 , AK2 are in the middle, ie in the area of the median plane M. , preferably in a common radial plane, perpendicular to the wheel and axis of rotation a , arranged, whereby installation space in the axial direction (in the direction of the wheel axis a ) is saved. The differential output shafts 3a , 3b As in the previous exemplary embodiments, each drive a constant transmission stage, designed as a third planetary gear set PS3 , which is the output shaft 2a , 2 B the drive wheels R1 , R2 drives.

The switching elements A. , B. , C. , D. , what a 5 on both sides, ie to the right and left of the axle differential DI are arranged, can also be radially outside of the axle differential DI are arranged, which also saves space in the axial direction.

6th shows a drive axle as a further embodiment of the invention 6th , in which the same reference numerals are used as before for the same parts. The difference here is that the first planetary gear set PS1 is designed as a so-called clutch variant, with its sun shaft SO1 - together with the ring gear shaft HR2 of the second planetary gear set PS2 - fixed to the housing is supported. The drive of the first planetary set PS1 is switchable, ie it takes place either by closing the switching element A. via the ring gear shaft HR1 or by closing the switching element B. over the web shaft ST1 . The drive shaft therefore drives in first gear 1a the first electric machine EM1 via the ring gear shaft HR1 the first planetary set PS1 on, which over its web wave ST1 and the sun wave SO2 of the second planetary gear set PS2 is coupled with this. Even with the drive axle 6th can use the second two planetary gear sets PS2 moved closer together in the axial direction and radially outside of the axle differential DI be arranged as in 3 at the drive axle 3 is shown.

7th shows a drive axle as a further embodiment of the invention 7th , the same reference numerals being used as before for the same parts. The difference here is that the second planetary set PS2 not - as in the previous exemplary embodiments - seen in the direction of force flow, in front of, but behind the axle differential DI is arranged and each of a differential output shaft 3a or. 3b is driven. The right and left of the median plane M. arranged second planetary gear sets PS2 are constant gear ratios, which are the third planetary gear sets PS3 are upstream in the area close to the wheel. The first planetary set PS1 thus forms the two-speed manual transmission alone and is via its ring gear shaft HR1 from the e-machine EM1 or. EM2 driven. The output takes place via the spider shaft ST1 , which is permanently connected to the axle differential Di. As in the previous exemplary embodiments, the gears are shifted via the shifting elements A. , C. (Sun wave SO1 fixed) and B, D (blocking of the first planetary gear set PS1 ). The advantage of this arrangement is that the axle differential Di is loaded with a lower torque and can therefore be made smaller; this also applies to the differential output shafts 3a , 3b . The support of the switching elements A. , C. on the housing GH is here in the area of the stationary part of the electric machines EM1 , EM2 , ie the stator (without reference number) arranged.

8th shows a drive axle as a further embodiment of the invention 8th , the same reference numerals being used as before for the same parts. Different from the drive axle 7th according to 7th is here the support of the switching elements A. and C. on the housing GH which is in the area of the rotors RO1 , RO2 , preferably in an area that is radially inward of the rotors RO1 , RO2 is arranged, extends. This gives the possibility that the housing GH in this area as the basis for mounting the electric machines EM1 , EM2 can serve. The switching elements FROM and CD , also as double switching elements FROM and CD at this point are very easily accessible for actuators (not shown). As mentioned above, when the switching element is closed A. respectively C is the sun wave SO1 of the first planetary gear set PS1 fixed.

9 shows as a further embodiment of the invention (in full representation) a drive axle 9 concerning the arrangement of the electrical machines EM1 , EM2 and the two-speed manual transmission G1 , G2 the drive axle 1 according to 1 corresponds. The same reference numerals are used for the same parts as in 1 used. What is different is that the drive axle 9 is designed as a so-called portal axis. The constant translation level according to 1 , designed as a third planetary set PS3 , is here through a portal step PO1 replaced, on both sides in the area of the drive wheels R1 , R2 . The portal step PO1 is designed as a planetary gear set and has a web 11 , Planetary gears 12 , 13 which opposite the jetty 11 are stored, a sun gear 14th as well as a ring gear 15th on. The bridge 11 is fixed to the housing, so the planetary gear set runs with a stationary transmission. They are driven by a differential output shaft 3a , 3b on the planet gear 12 . The output takes place via the ring gear 15th on the output shaft 2a and thus on the drive wheel R1 . The portal step PO1 points between its drive shaft, the differential output shaft 3a , and its output shaft 2a an offset h1 on. This gear arrangement with an offset is referred to as a portal axis and has the advantage of greater ground clearance for the vehicle compared to the variants described above; this means that electric machines with a larger diameter can be used. As a result of the drive via the planetary gear 12 and due to further planet gears on the circumference, a division of the power flow from the input to the output is achieved. The portal step PO1 on the right, which is the right drive wheel R2 is a mirror image of the portal step PO1 formed on the left side and has the same translation into slow speed.

10 shows a drive axle as a further embodiment of the invention 10 which is the drive axle 9 according to 9 but a modified portal level PO2 having. The same reference symbols are used for the same parts. The portal step PO2 is designed as a spur gear and has one of the differential output shaft 3a driven drive gear 21st , two intermediate gears 22nd , 23 as well as an output gear 24 on, which is via the output shaft 2a the wheel R1 drives. Between the drive shaft of the second portal stage PO2 , ie the differential output shaft 3a and the output shaft 2 B there is an offset h2 . The two intermediate gears 22nd , 23 are rotated in the plane of the drawing for the sake of illustration - they stand with both the drive gear 21st as well as with the output gear 24 in meshing. Through the arrangement of the intermediate gears 22nd , 23 becomes the center distance between the drive gear 21st and the output gear 24 enlarged. It also results from the two intermediate gears 22nd , 23 a division of services. The one from the differential output shaft 3b drivable portal step PO2 on the right side is a mirror image of the portal step PO1 on the left and has the same translation.

The offset h2 at the portal step PO2 ( 10 ) is assumed to be the same for both portal levels PO1 , PO2 greater than the offset h1 at the portal step PO1 ( 9 ) - this is also shown in the drawings: h2> h1.

The two electrical machines EM1 , EM2 can also be composed of several sub-machines, which are also connected to the drive shafts by further gear elements 1a , 1b can be connected.

A retarder (e.g. an eddy current brake or a hydraulic retarder) can be coupled to each of the shafts mentioned above.

List of reference symbols

1

Drive axle

1a

Drive shaft ( EM1 )

1b

Drive shaft ( EM2 )

2

Drive axle

2a

Output shaft

2 B

Output shaft

3

Drive axle

3a

Differential output shaft

3b

Differential output shaft

4th

Drive axle

5

Drive axle

6

Drive axle

7th

Drive axle

8th

Drive axle

9

Drive axle

10

Drive axle

11

Bridge (PO1)

12

Planetary gear

13th

Planetary gear

14th

Sun gear

15th

Ring gear

21st

Drive gear ( PO2 )

22nd

Intermediate gear

23

Intermediate gear

24

Output gear

a

Wheel axle

A1

first drive train

A2

second drive train

AK1

first actuator

AK2

second actuator

A, B

Switching elements ( G1 )

C, D

Switching elements ( G2 )

DI

differential

DIK

Differential basket

E.

Switching element

EM1

first electric machine

EM2

second electric machine

G1

first manual transmission

G2

second manual transmission

G1a

first manual transmission

G2a

second manual transmission

GH

casing

h1

Offset ( PO1 )

h2

Offset ( PO2 )

HR1

Ring gear shaft ( PS1 )

HR2

Ring gear shaft ( PS2 )

HR3

Ring gear shaft ( PS3 )

M.

Middle plane

PO1

first portal level

PO2

second portal level

PS1

first planetary set

PS2

second planetary set

PS3

third planetary set

R1

first (left) drive wheel

R2

second (right) drive wheel

RO1

first rotor ( EM1 )

RO2

second rotor ( EM2 )

SO1

Sun wave ( PS1 )

SO2

Sun wave ( PS2 )

SO3

Sun wave ( PS3 )

ST1

Web shaft ( PS1 )

ST2

Web shaft ( PS2 )

ST3

Web shaft ( PS3 )

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 2450597 A1 [0002]

Claims (29)

Drive axle for an electrically drivable vehicle with two drive wheels (R1, R2) and a common wheel axle (a), comprising two electrical machines (EM1, EM2), two two-speed gearboxes (G1, G1a, G2, G2a), an axle differential (DI ) between the drive wheels (R1, R2), the first electric machine (EM1) and the first two-speed gearbox (G1) having a first drive train (A1) and the second electric machine (EM2) and the second two-speed gearbox (G2) Form a second drive train (A2), both drive trains (A1, A2) driving into the axle differential (DI) and the first and second two-speed gearboxes (G1, G2) each having a switchable first planetary gear set (PS1) each with a spider shaft (ST1), a sun shaft (SO1) and a ring gear shaft (HR1). Drive axle after Claim 1 , characterized in that the switchable first planetary gear set (PS1) of the first two-speed manual transmission (G1, G1a) has two first switching elements (A, B) and the switchable first planetary set (PS1) of the second two-speed manual transmission (G2, G2a) has two more Shift elements (C, D) are assigned, and that a first and a second gear can be shifted with the first and the further shift elements (A, B, C, D). Drive axle after Claim 2 , characterized in that the switching elements are designed as unsynchronized claw switching elements (A, B, C, D). Drive axle after Claim 1 , 2 or 3 , characterized in that the switchable first planetary gear set (PS1) of the first two-speed gearbox (G1, G1a) via its ring gear shaft (HR1) and the switchable first planetary set (PS1) of the second two-speed gearbox (G2, G2a) via its ring gear shaft ( HR1) can be driven. Drive axle after Claim 4 , characterized in that the ring gear shafts (HR1) of the first and the second two-speed gearbox (G1, G2) can be driven by the first and the second electrical machine (EM1, EM2). Drive axle after Claim 1 to 5 , characterized in that the two-speed manual transmissions (G1, G1a, G2, G2a) each have a second planetary set (PS2) which is designed as a constant transmission stage. Drive axle after Claim 6 , characterized in that the spider shaft (ST1) of the first planetary set (PS1) is coupled to the sun shaft (SO2) of the second planetary set (PS2). Drive axle after Claim 6 or 7th , characterized in that the ring gear shafts (HR2) of the second planetary sets (PS2) are preferably jointly supported on the housing side. Drive axle after Claim 6 , 7th or 8th , characterized in that the spider shafts (ST2) of the second planetary gear sets (PS2) are connected to the axle differential (DI). Drive axis according to one of the Claims 6 to 9 , characterized in that the second planetary sets (PS2) of the two two-speed manual transmissions (G1, G2) and the axle differential (DI) are arranged in the area of a central plane (M) and the axle differential (DI) are arranged radially within the second planetary sets (PS2) . Drive axle after Claim 1 , 2 , 3 or 4th , characterized in that the first two-speed gearbox (G1a) and the second two-speed gearbox (G2a) each have second planetary gear sets (PS2), each via their sun shafts (SO2) from the first electrical machine (EM1) and from the second electrical machine (EM2) can be driven. Drive axle after Claim 11 , characterized in that the spider shaft (ST2) of the second planetary set (PS2) is firmly connected to the ring gear shaft (HR1) of the first planetary set (PS1). Drive axle after Claim 11 or 12 , characterized in that the ring gear shaft (HR2) of the second planetary gear set (PS2) is fixed. Drive axle after Claim 11 , 12 or 13 , characterized in that the spider shafts (ST1) of the first planetary sets (PS1) of the first and the second two-speed gearbox (G1a, G2a) are connected to the axle differential (DI). Drive axis according to one of the Claims 2 to 14th , characterized in that the first gear can be shifted by coupling the sun shaft (SO1) of the first planetary gear set (PS1) to the housing. Drive axle after Claim 15 , characterized in that the second gear can be shifted by "locking" the first planetary gear set (PS1) by two of the three shafts (SO1, HR1, ST1), in particular the sun shaft (SO1) and the web shaft (ST1) or the sun shaft ( SO1) and the ring gear shaft (HR1) are coupled together. Drive axis according to one of the Claims 1 to 16 , characterized in that the electrical machines (EM1, EM2) and the two-speed Gearboxes (G1, G1a, G2, G2a) are arranged symmetrically with respect to a central plane (M), perpendicular to the wheel axis (a), and coaxially to the wheel axis (a). Drive axis according to one of the Claims 1 to 17th , characterized in that the axle differential (DI) is assigned a switching element (E) via which the axle differential (DI) can be locked. Drive axle after Claim 1 to 9 , characterized in that the shiftable first planetary set (PS1) can be driven in first gear via its ring gear shaft (HR1) and in second gear via its spider shaft (ST1). Drive axle after Claim 19 , characterized in that the spider shaft (ST1) of the first planetary set (PS1) is firmly connected to the sun shaft (SO2) of the second planetary set (PS2). Drive axle after Claim 19 or 20th , characterized in that the sun shaft (SO1) of the first planetary set (PS1) and the ring gear shaft (HR2) of the second planetary set (PS2) are supported on the housing side. Drive axle after Claim 6 , characterized in that the second planetary gear sets (PS2) are arranged behind the axle differential (DI), seen in the direction of force flow. Drive axle after Claim 22 , characterized in that the housing-side support (GH) of the first switching elements (A, C) is arranged in the area, preferably radially within the first and the second electrical machine (EM1, EM2). Drive axle according to one of the preceding claims, characterized in that, viewed in the direction of force flow, a further constant gear ratio stage (PS3, PO1, PO2) is arranged behind the axle differential (DI) in the area of the drive wheels (R1, R2). Drive axle after Claim 24 , characterized in that the further constant transmission stages are designed as third planetary gear sets (PS3) each with a sun shaft (SO3), a spider shaft (ST3) and a fixed ring gear shaft (HR3), the sun shafts (SO3) being driven directly or indirectly by the differential output shafts and the spider shafts (ST3) are connected to the drive wheels (R1, R2). Drive axle after Claim 24 , characterized in that the further constant transmission stages are designed as portal stages (PO1, PO2) each with a drive shaft (3a, 3b) and an output shaft (2a, 2b) and that the drive shafts (3a, 3b) and the output shafts (2a, 2b) are arranged with an offset (h1, h2) to each other. Drive axle after Claim 26 , characterized in that the portal step (PO1) has a web (11) with planetary gears (12, 13), a sun gear (14) and a ring gear (15) that the web (11) is held, the drive via one of the Planet gears (12, 13) and the output take place via the ring gear (15). Drive axle after Claim 26 , characterized in that the portal stage (PO2) has a drive gear (21), two intermediate gears (22, 23) and a driven gear (24), the intermediate gears (22, 23) both with the drive gear (21) and with the Output gear (24) are in engagement. Drive axis according to one of the Claims 1 to 28 , characterized in that the electrical machines (EM1, EM2) have rotors (RO1, RO2) and that within the rotors (RO1, RO2) the first planetary sets (PS1) and / or the second planetary sets (PS2) and / or the axle differential (DI) are at least partially arranged.

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