EP1888392A1

EP1888392A1 - Electric drive system comprising differential steering for a vehicle, drive unit and vehicle

Info

Publication number: EP1888392A1
Application number: EP06754183A
Authority: EP
Inventors: Ralf Boss; Hans-Peter Freudenreich
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2005-06-10
Filing date: 2006-06-07
Publication date: 2008-02-20
Also published as: DE102005027117A1; WO2006131332A1; US20080210481A1; KR20080014993A

Abstract

The invention relates to an electric drive system (10) for a vehicle comprising differential steering. Said system comprises two similar drive units (20, 22), an electric energy source (13, 15, 16, 18), an electronic control unit (36) and a left and right summarising gear, which are configured as planetary gears. One drive unit drives the ring gear (48) of the left summarising gear, whilst the other drive unit drives the ring gear (56) of the right summarising gear. The ring gear (48) of the left summarising gear has a direct drive connection with the sun gear (54) of the right summarising gear by means of a mechanical gear train, whilst the ring gear (56) of the right summarising gear has a direct drive connection with the sun gear (46) of the left summarising gear by means of a second mechanical gear train. According to the invention, a left sun gear shaft (60) runs through a left hollow shaft (58) towards the centre of the vehicle and a right sun gear shaft (64) runs through a right hollow shaft (62) towards the centre of the vehicle.

Description

ELECTRIC DRIVE SYSTEM WITH STEERING CONTROL FOR ONE VEHICLE, TRANSMISSION UNIT AND VEHICLE

The invention relates to an electric drive system for a vehicle with slip-lock according to the preamble of the main claim, a transmission unit of such a drive system and a vehicle equipped therewith.

Rolling stock vehicles are tracked vehicles or wheeled vehicles in which the curve-inner chain or the inner drive wheels are slowed down in relation to the curve-outer chain or the outer drive wheels for cornering. Especially with heavy tracked vehicles, this requires considerable braking power at the inside of the bend.

Various systems are known, which allow to use this braking power by being fed to the curve outer chain. In a mechanical or hydrostatic-mechanical superimposed steering gear with a steering gear part and a drive gear part, as disclosed in DE 38 33 784 A1, this is provided for a driven by the steering gear part zero shaft. The exchange of power from the inside-the-inside chain to the outside-out chain is done mechanically via the drive section.

In the diesel-electric drive system disclosed in DE 100 05 527 A, each of the two chains is assigned its own electric drive system, with no mechanical drive connection therebetween. The power transmission between left and right side takes place exclusively by electrical means, which allows a space-saving arrangement of the drive elements, but a correspondingly powerful electrical see plant and powerful electric drive machines required. EP 0 304 594 likewise shows a diesel-electric drive system which also has a mechanical superposition steering gear. For driving and steering drive in each case an electric drive motor of different sizes is provided. In this drive system, the power transmission between the left and right sides takes place exclusively mechanically. However, this known drive system is very complicated and not optimal in terms of space, since not only a diesel engine and a complex mechanical superimposed steering gear, but also a powerful generator and two electric drive machines are needed. When driving straight ahead, only the traction drive motor is loaded while the power installed in the steering drive motor is not used.

WO 02/083483 A shows a drive system in which similar electric traction drive machines are arranged on each side and in which, moreover, a central third electric motor is provided as the steering motor.

The US 5,445,234 shows a drive system for a vehicle with anti-slip steering with a left and a similar right electric drive machine. In this electric drive system, both electric drive machines serve both as a driving and as a steering drive at the same time. The full installed electric drive power is available for straight ahead driving. The power transmission between the left and right side takes place partly mechanically and partly electrically. On each side of a designed as a planetary gear summation gear is arranged. The planet carriers of these two summation gears form the two power take-offs which act on the caterpillars. The sun gear of the left summation gear is a spur gear from the left prime mover and the sun gear of the right Summierungsgetriebes via a spur gear from the right Drive machine driven. The two ring gears of the left and right summation are connected by a connecting shaft torsionally rigid with each other. In addition, a gear train is arranged between the sun gear of the left summation gear and the sun gear of the right summation gear, which also couples the two drive machines together. Thus, when cornering the two prime movers can be operated at different speeds, this gear train centered on a differential gear.

Finally, the closest considered WO 2005/039958 A1 shows an electric drive system for a vehicle with anti-slip steering with a left and a similar right electric drive machine, with a combination of diesel engine and generator as electrical energy source, an electronic control device for independent control of speeds at the two prime movers, with a left and a similar right summation, which are designed as a planetary gear, wherein the planet carrier form the output and wherein the ring gear of the left summation gear driving directly from the left prime mover and the ring gear of the right summation gear drivable directly from the right drive machine drivable is, and wherein the ring gear of the left summation gear is connected by a first mechanical gear train directly to the sun gear of the right summation gear, and the ring gear of the right Su mmierungsgetriebes is drivingly connected by a second mechanical gear train directly connected to the sun gear of the left summation.

This electromechanical drive system advantageously has only a few different components and two identical drive machines. Both drive machines are used both as a travel drive and as a steering drive. The drive system moreover has the me- a very good efficiency between left and right side, so that relatively small and compact electric drive machines can be used.

However, in this system, the mechanical, crosswise driving connection between the left and the right summation gear is realized by connecting shafts, which are guided around the outside of the summation gear. This arrangement requires relatively long connection shafts and restrictions in terms of a compact design.

The present invention is therefore an object of the invention to provide a generic drive system, a transmission unit for this purpose and a vehicle equipped with it, with the improved use of the limited space can be achieved by a more compact design.

According to the invention this object is achieved by a, also the features of the characterizing part of the main claim exhibiting electric Antriebssytem or a transmission unit for this or a vehicle equipped therewith.

Advantageous embodiments are given by the dependent claims.

In the electric drive system according to the invention, therefore, the designated as "left" ring gear ring gear of the left summation located on a "left" hollow shaft. In this hollow shaft, the designated as "left" sun gear shaft, which carries the sun gear of the left summation, guided in the direction of the vehicle center. Symmetrically, a "right" sun gear is guided through a "right" hollow shaft, on which the "right" ring gear sits in the direction of the center of the vehicle. The drive connection between the ring gear of the left summation gear and the sun gear of the right The summation gear and between the ring gear of the right summation gear and the sun gear of the left summation gear are produced by connecting the left hollow shaft directly to the right sun gear shaft and the right hollow shaft directly to the left sun gear shaft. In the context of the present invention, a "direct drive connection" means that rotation of one part is directly associated with rotation of the other part. A drive-direct connection can be a torsionally rigid connection or else a connection via a gear chain of a gear train.

Advantageously, the crosswise connection of the hollow or sun gears of the two summation transmissions does not take place around the outside of the summation gear, but along the main axis of the summation in concentrically rotating shafts. It can be used much shorter connection shafts, which can also be arranged in the area of the vehicle center and within a limited by the two ring gears of the summation gear cylinder space. Thus, all mechanical transmission elements are combined in a compact gear housing with high packing density.

The direct drive connections can be made in a simple manner by the left hollow shaft is drivingly connected to the right Sonnenradwelle by a first intermediate shaft on which a first and a second gear are arranged, wherein the first gear with a sitting on the left hollow shaft third gear and the second gear are in engagement with a seated on the right sun gear fourth gear, and that the right hollow shaft with the left Sonnenradwelle is drivingly connected by a second intermediate shaft on which a fifth and a sixth gear are arranged, the fifth Gear with a seated on the right hollow shaft seventh gear and the sixth gear with engage an 8th gear seated on the left sun gear shaft.

In this embodiment of the invention, the structure of the transmission can be symmetrical, with each component, including the intermediate shafts, is used twice with the gears arranged thereon. Overall, in this way only a few different components are required to build, which offers great advantages in terms of manufacturing costs and spare parts inventory.

In a further embodiment of the invention, the two drive machines are arranged offset relative to a central axis of the summation. Here, the left ring gear of the first drive machine via a pair of gears can be driven, which is formed of a arranged on an output shaft of the first drive machine ninth gear and arranged on the left hollow shaft tenth gear. The right ring gear can be driven by the second drive machine via a pair of gears, which is formed from a arranged on an output shaft of the second drive engine eleventh gear and arranged on the right hollow shaft twelfth gear.

The advantage of this embodiment of the invention is that a resolved construction is achieved, in which the electric drive machines are arranged offset outwards. There, among other things, they are easily accessible for maintenance work. The offset relative to the center axis of the summation gear arrangement of the two drive motors allows them to be arranged where free space is available, for example, above the caterpillars. Another advantage of this embodiment of the invention is that the overall length of the transmission can be significantly reduced.

If extreme demands are placed both on the climbing ability of the vehicle and on the maximum speed to be reached, it is possible to connect the first drive machine with the left ring gear and the second drive machine with the right ring gear selectively with different shiftable ratios. The additional effort that is required in the transmission through the other translations and the necessary switching elements, such as multi-plate clutches or jaw clutches, pays off in that smaller, lighter and cheaper electric drive machines can be used.

The invention and further advantageous embodiments will be explained in more detail with reference to the accompanying figures. Show:

Fig. 1 shows schematically a vehicle with slide-steering;

Fig. 2 shows schematically an electric drive system for a vehicle with slipping and

Fig. 3 shows schematically various embodiments of Getriebebis 6 units with flanged electric drive machines.

In Fig. 1, 2 denotes a vehicle with slip-steering, which in addition to a vehicle pan 4, a left crawler 6, a right track 8 and an electric drive system 10, the output shafts 12, 14, the two crawlers 6, 8 drive. As shown in Fig. 2, the electric drive system 10 has two similar electric drive machines 20, 22, each having two independent windings, which are controlled independently of each other. Combinations of diesel engines 13, 15 with electric generators 16, 18 serve as electrical energy sources. The electric generators 16, 18 are electrically connected to the electric drive machines 20 via power electronics which comprise rectifiers 24, 26 and inverters 28, 30, 32, 34 , 22 connected. The individual components are controlled by the electronic control device 36 via signal lines shown in dashed lines in such a way that predetermined, predetermined speeds are set independently of the drive machines 20, 22. With 38, the gear unit is designated, which has the two output shafts 12, 14 for driving the two track tracks.

The transmission unit 38 shown in FIG. 3 is driven by the two electric drive machines 20, 22. All mechanical transmission parts are housed in a transmission housing 40, which has a left output 12 and a right output 14. The output 12 is connected to the planetary carrier 42 of the left summation gear on which a plurality of planet gears 44 are rotatably mounted, which are in simultaneous engagement with the sun gear 46 and the ring gear 48. The right summation gear is identically constructed and is formed by the planet carrier 50, the planet wheels 52, the sun gear 54 and the ring gear 56. The "left" ring gear 48 of the left summation gear sits on a hollow shaft 58, through which the "left" sun gear 60 is guided in the direction of the vehicle center. Accordingly, the "right" ring gear 56 is seated on a right hollow shaft 62, through which the "right" sun gear 64 is guided in the direction of the vehicle center. The left hollow shaft 58 is drivingly connected to the right sun gear shaft 64 by a first intermediate shaft 66 on which a gear Z1 and a gear Z2 are arranged, wherein the tooth wheel Z1 with the sitting on the left hollow shaft gear Z3 and the gear Z2 with the seated on the right sun gear 64 gear Z4 are engaged. The drive connection of the right hollow shaft 62 with the left Sonnenradwelle 60 is made by the second intermediate shaft 68 on which the gear Z5 and the gear Z6 are arranged, wherein the gear Z5 with a seated on the right hollow shaft 62 gear Z7 and the gear Z6 with the sitting on the left sun gear 60 gear Z8 are engaged.

The left hollow shaft 58 and the left ring gear 48 is drivable directly from the left drive machine 20 drivable. For this purpose, a pair of gears, which is formed from the arranged on the output shaft 70 of the left drive machine 20 gear Z9 and arranged on the left hollow shaft 58 gear Z10.

The two electric drive machines 20, 22 are arranged offset in parallel with respect to the central axis of the two summation gear.

In a corresponding manner, the right hollow shaft 62 and the right ring gear 56 can be driven directly by the right electric drive machine 22. Serve this purpose, the gear Z11, which is arranged on the output shaft 72 of the right electric drive machine 22, and which is in engagement with the arranged on the right hollow shaft 62 gear Z12 in engagement.

The embodiment shown in FIG. 4 differs from the embodiment shown in FIG. 3 in that the left drive machine 20 with the left ring gear 48 and the right drive machine 22 with the right ring gear 56 can be selectively connected to different shiftable ratios. Otherwise, the same reference numerals as in Fig. 3 are used in Figs. 4, 5 and 6. On the left hollow shaft 58 serving as a switching element jaw clutch 74 is arranged. Depending on the switching position of the sliding sleeve 76 is optionally the gear Z10 or the gear Z13 with the left hollow shaft 58 coupled. On the output shaft 70 of the left electric drive machine 20, the gear Z14 is arranged in addition to the gear Z9, which is in engagement with the gear Z13. For high torque requirements, eg. B. steep inclines, is driven via the gear pair Z14, Z13, while for highest vehicle speeds with the gear pair Z9, Z10 is driven. Instead of the dog clutch 74 shown schematically also a power shift hydraulic multi-disc clutch can be used as a switching element.

On the right side, the shiftable ratios are correspondingly formed by the dog clutch 78, the sliding sleeve 80, the gear Z15 and the gear Z16.

FIGS. 5 and 6 show alternative embodiments of electric drive systems according to the invention, in which the two drive machines 20, 22 are arranged concentrically on the left-hand hollow shaft 58 and the right-hand hollow shaft 62, respectively. Both the hollow shafts 58, 62 and the sun gear shafts 60, 64 penetrate the electric drive machines. The respective associated hollow shaft is at the same time output shaft of the electric drive machines.

Fig. 6 shows an embodiment of the invention, in which the left electric drive machine 20 with the right sun gear 54 and the right electric drive machine 22 with the left sun gear 46 is selectively connectable with different switchable gear ratios. For this purpose, on the first intermediate shaft 66 serving as a switching element jaw clutch 82 is arranged. By shifting the sliding sleeve 84 of the dog clutch 82 is optionally the gear Z1 or the gear Z17 with the first intermediate shaft 66 coupled while the gear Z1 in constant engagement with the seated on the left hollow shaft 58 gear Z3 and the gear Z17 in constant engagement with the also on the left hollow shaft 58 seated gear Z18. In a corresponding manner, a dog clutch 86 is arranged on the second intermediate shaft 68. By shifting the sliding sleeve 88 is optionally the gear Z5 or the gear Z19 with the second intermediate shaft 68 coupled while the gear Z5 is in constant mesh on the right hollow shaft 62 seated gear Z7 and the gear Z19 in constant engagement with a likewise on the Right hollow shaft 62 seated gear Z20 is.

reference numeral

2 vehicle

4 vehicle trough

6, 8 crawlers

10 drive system

12, 14 output shafts

13, 15 internal combustion engines

16, 18 electric generators

20, 22 electric drive machines

24, 26 Rectifiers 8, 30, 32, 34 inverters

36 electronic control device

38 Gear unit 0 Gear housing 2 Planet carrier 4 Planetary wheels 6 Sun gear 8 Ring gear 0 Planet carrier 2 Planetary gears 4 Sun gear 6 Ring gear 8 Hollow shaft 0 Sun gear shaft 2 Hollow shaft 4 Sun gear shaft 6 Intermediate shaft 8 Intermediate shaft 70 prime mover output shaft

72 prime mover output shaft

74 dog clutch

76 sliding sleeve

78 dog clutch

80 sliding sleeve

82 dog clutch

84 sliding sleeve

86 dog clutch

88 sliding sleeve

Z1 to Z20 gears

Claims

Patent claims

Electric drive system (10) for a vehicle (2) with slide-steering with at least a first (20) and a similar second electric drive machine (22), an electrical energy source (13, 16, 15, 18), an electronic control device (36 ) for the independent control of rotational speeds on the first and second drive machine (20, 22), designed as a planetary gear left summation gear, with a left output forming the left planet carrier (42), a left ring gear (48) and a left sun gear (46) a right right summation gear having a right output planetary carrier (50), a right ring gear (56) and a right sun gear (54), said left ring gear (48) driving directly from said first drive machine (20) and right ring gear (56) is drivable directly from the second drive machine (22), wherein the left ring gear (48) by a first mechanical Ge drive train (58, Z3, Z1; 66, Z2, Z4; 64) is drivingly connected directly to the right sun gear (54), and the right ring gear (56) is driven directly by a second mechanical gear train (62, Z7, Z5; 68, Z6, Z8; 60) directly to the left sun gear (46 ), characterized in that a left Sonnenradwelle (60) through a left hollow shaft (58) on which the left ring gear (48) sits, is guided in the direction of the vehicle center and a right Sonnenradwelle (64) by a right hollow shaft ( 62) on the right ring gear (56) is seated, is guided in the direction of the vehicle center and the left hollow shaft (58) drivingly directly with the right Sonnenradwel- Ie (64) and the right hollow shaft (62) drivingly directly with the left sun gear ( 60) is connected.

2. Electric drive system according to claim 1, characterized in that the left hollow shaft (58) with the right Sonnenradwel- Ie (64) is drivingly connected by a first intermediate shaft (66) on which a first and a second gear (Z1, Z2 ), wherein the first gear (Z1) with a on the left hollow shaft (58) seated third gear (Z3) and the second gear (Z2) with a on the right sun gear (64) seated fourth gear (Z4) and that the right hollow shaft (62) is drivingly connected to the left sun gear shaft (60) by a second intermediate shaft (68) on which fifth and sixth gears (Z5, Z6) are arranged, the fifth gear (Z5) with a on the right hollow shaft (62) seated seventh gear (Z7) and the sixth gear (Z6) with an on the left Sonnenradwelle (60) seated eighth gear (Z8) are engaged.

3. Electric drive system according to claim 1 or 2, characterized in that the left ring gear (48) of the first drive machine (20) via a pair of gears can be driven, which consists of a on an output shaft (70) of the first drive machine (20) arranged ninth Gear (Z9) and one on the left hollow shaft (58) arranged tenth gear (Z10) is formed, that the right ring gear (56) from the second drive machine (22) via a pair of gears is driven, which consists of a on an output shaft (72 ) of the second drive machine (22) arranged eleventh gear (Z11) and one on the right hollow shaft (62) arranged twelfth gear (Z12) is formed, and that the two drive machine NEN (20, 22) are arranged offset from a central axis of the summation.

4. Electric drive system according to one of claims 1 to 3, characterized in that the first drive machine (20) with the left ring gear (48) and the second drive machine (22) with the right ring gear (56) selectively connectable with different switchable gear ratios is.

5. An electric drive system according to claim 3 and 4, characterized in that on the left hollow shaft (58) a switching element (74) is arranged with the optional tenth gear (Z10) or a thirteenth gear (Z13) with the left hollow shaft ( 58) is coupled while the tenth gear (Z10) is in constant mesh with the ninth gear (Z9) rotatably mounted on the output shaft (70) of the first prime mover (20) and the thirteenth gear (Z13) is in constant mesh with one also on the output shaft (70) of the first drive machine (20) non-rotatably mounted fourteenth gear (Z14), and that on the right hollow shaft (62) a switching element (78) is arranged with the optional the twelfth gear (Z12) or a fifteenth Gear (Z15) with the right hollow shaft (62) is coupled, while the twelfth gear (Z12) in constant engagement with the on the output shaft (72) of the second drive machine (22) rotatably arranged eleventh Gear (Z11) and the fifteenth gear (Z5) in constant engagement with a likewise on the output shaft (72) of the second drive machine (22) rotatably mounted sixteenth gear (Z 16)

6. The electric drive system according to claim 1 or 2, characterized in that the first drive machine (20) is arranged concentrically on the left hollow shaft (58) and the second drive machine (22) concentrically on the right hollow shaft (62).

7. An electric drive system according to claim 4 and 6, characterized in that one of the first drive machine (20) with the right sun gear (54) and the second drive machine (22) with the left sun gear (46) is selectively connectable with different switchable gear ratios.

8. An electric drive system according to claim 7, characterized - eichnet that on the first intermediate shaft (66) a switching element (82) is arranged, with which optionally the first gear (Z1) or a seventeenth gear (Z17) with the first intermediate shaft ( 66), while the first gear (Z1) is in constant mesh with the third gear (Z3) seated on the left-hand hollow shaft (58) and the seventeenth gear (Z17) is in constant mesh with a likewise on the left-hand quill (58) ) is seated eighteenth gear (Z18), and that on the second intermediate shaft (68) a switching element (86) is arranged, with which selectively the fifth gear (Z5) or a nineteenth gear (Z19) with the second intermediate shaft (68) coupled while the fifth gear (Z5) is in constant mesh with the seventh gear (Z7) seated on the right quill (62), and the nineteenth gear (Z19) is in constant mesh with one also on the right H ohlwelle (62) sitting twentieth gear (Z20) is.

9. gear unit of an electric drive system according to any one of the preceding claims, which at least the two summation transmission comprises and structurally combined in a housing (40).

10. vehicle with an electric drive system according to one of claims 1 to 8.