CN114030348A

CN114030348A - Electric drive axle

Info

Publication number: CN114030348A
Application number: CN202111278841.5A
Authority: CN
Inventors: 陈小江; 唐子威; 贾军风; 彭政洲; 林广镇
Original assignee: If Technology Co Ltd
Current assignee: If Technology Co Ltd
Priority date: 2021-10-31
Filing date: 2021-10-31
Publication date: 2022-02-11

Abstract

The invention provides an electric drive axle, which comprises a plurality of motors, two output half shafts and a central shaft, wherein the two output half shafts are connected through a differential mechanism; each first transmission mechanism is provided with a first intermediate shaft, a first gear shifting device, a first gear transmission unit and a second gear transmission unit; the second transmission mechanism is provided with a second gear shifting device, and a third gear transmission unit and a fourth gear transmission unit with different transmission ratios are arranged between the second gear shifting device and the differential mechanism; the third transmission mechanism is provided with a third gear shifting device sleeved on the central shaft, and the central shaft can be directly connected with the differential in a transmission mode through the connection of the third gear shifting device. The electric drive axle is convenient for adjusting gears, outputs different torques and is beneficial to improving the reliability of the electric drive axle in use.

Description

Electric drive axle

Technical Field

The invention relates to the technical field of automobile parts, in particular to an electric drive axle.

Background

With the increasing requirements of the country on energy conservation and environmental protection and the continuous enhancement of the environmental awareness of people, electric automobiles are favored by more and more people and become one of the main transportation tools for people to go out daily. However, most of the existing electric automobiles adopt a driving system with a single motor and a fixed reduction ratio mechanism, and the driving system is provided with a plurality of gears, so that the overall structure is more complex. Not only results in a large structural size, but also is disadvantageous for arrangement in the entire vehicle. And when the motor breaks down, the automobile can not run, and the reliability of the automobile in use is seriously influenced.

Disclosure of Invention

In view of the above, the present invention is directed to an electric drive axle, which facilitates gear adjustment and is beneficial to improve reliability in use.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

an electric drive axle comprising a plurality of electric motors, two output half shafts connected by a differential, and a central shaft fitted around one of said output half shafts, wherein:

a first transmission mechanism is arranged between each motor and the central shaft, and a second transmission mechanism and a third transmission mechanism are arranged between the central shaft and the differential mechanism;

each first transmission mechanism is provided with a first intermediate shaft in transmission connection with the motor, a first gear shifting device sleeved on the first intermediate shaft, and a first gear transmission unit and a second gear transmission unit which are arranged between the first gear shifting device and the central shaft and have different transmission ratios, and the first gear shifting device can be alternatively in transmission connection with the central shaft through the first gear transmission unit or the second gear transmission unit;

the second transmission mechanism is provided with a second gear shifting device sleeved on the central shaft, a third gear transmission unit and a fourth gear transmission unit with different transmission ratios are arranged between the second gear shifting device and the differential, and the second gear shifting device can be alternatively connected with the differential in a transmission mode through the third gear transmission unit or the fourth gear transmission unit;

the third transmission mechanism is provided with a third gear shifting device sleeved on the central shaft, and the central shaft can be directly connected with the differential in a transmission mode through the connection of the third gear shifting device.

Further, the first gear transmission unit includes a first driving gear provided on one side of the first gear shift device, and a first driven gear provided on the central shaft and engaged with the first driving gear; the second gear transmission unit comprises a second driving gear arranged on the other side of the first gear shifting device and a second driven gear arranged on the central shaft and meshed with the second driving gear; the first gear transmission units share one first driven gear, and/or the second gear transmission units share one second driven gear.

Furthermore, a second intermediate shaft is arranged on the radial outer side of the central shaft, and the second intermediate shafts are in transmission connection with the differential through a second transmission gear set; and the third gear transmission unit and the fourth gear transmission unit are in transmission connection with the differential mechanism through the second intermediate shaft.

Further, the third gear transmission unit includes a third driving gear provided on one side of the second shifting device, and a third driven gear provided on the second countershaft and engaged with the third driving gear; the fourth gear transmission unit comprises a fourth driving gear arranged on the other side of the second gear shifting device and a fourth driven gear arranged on the second intermediate shaft and meshed with the fourth driving gear.

Further, the second transmission gear set comprises a sixth driven gear connected to the differential and sixth driving gears respectively arranged on the second intermediate shafts, and each of the sixth driving gears is meshed with the sixth driven gear.

Further, the motor is arranged coaxially with the first intermediate shaft and connected to one end of the first intermediate shaft; alternatively, the motor is coupled to the first intermediate shaft via a first transfer gear set, offset to one side of the first intermediate shaft.

Further, the radial distances between the second intermediate shaft and the central shaft and between the first intermediate shaft and the central shaft are the same or different, the differential is arranged at one end of the electric drive axle, and each motor is arranged at the other end of the electric drive axle relative to the differential.

Further, the motor is connected with the first intermediate shaft through a first transmission gear set and is offset to one side of the first intermediate shaft; the second intermediate shaft and the first intermediate shaft are arranged in a parallel and staggered mode on the radial outer side of the central shaft, the motor and the second intermediate shaft are arranged in a parallel and staggered mode on the radial outer side of the central shaft, and the motor is arranged close to the differential.

Furthermore, the two output half shafts are respectively provided with a planetary gear speed reducing mechanism, and each output half shaft is in transmission connection with the wheel through the planetary gear speed reducing mechanism.

Further, the first transmission gear set comprises a fifth driving gear arranged on the motor and a fifth driven gear arranged on the first intermediate shaft and meshed with the fifth driving gear, and the outer diameter of the fifth driving gear is smaller than that of the fifth driven gear.

Compared with the prior art, the invention has the following advantages:

according to the electric drive axle, the first gear shifting device can be alternatively connected with the central shaft in a transmission mode through the first gear transmission unit or the second gear transmission unit, the second gear shifting device can be alternatively connected with the differential mechanism in a transmission mode through the third gear transmission unit or the fourth gear transmission unit, the central shaft is directly connected with the differential mechanism in a transmission mode through the third gear shifting device, gear adjustment is facilitated, different torques are output, and meanwhile, the reliability and the stability of the electric drive axle in use can be improved through the arrangement of the double motors and the central shaft.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of an electric drive axle according to a first embodiment of the present invention;

fig. 2 is another schematic structural diagram of an electric drive axle according to a second embodiment of the present invention;

fig. 3 is a schematic structural diagram of an electric drive axle according to a second embodiment of the present invention;

fig. 4 is another schematic structural diagram of an electric drive axle according to the second embodiment of the present invention;

description of reference numerals:

1. a first motor; 2. a second motor; 3. a first shifting device; 4. a second shifting device; 5. a third shifting device;

10. a first motor output shaft; 11. a fifth driving gear; 12. a fifth driven gear; 13. a second motor output shaft;

30. a first intermediate shaft; 31. a first drive gear; 32. a second driving gear;

40. a central shaft; 41. a first driven gear; 42. a second driven gear;

50. a second intermediate shaft; 51. a third driving gear; 52. a fourth driving gear; 54. a sixth driving gear; 55. a third driven gear; 56. a fourth driven gear;

60. an output half shaft; 62. a differential mechanism; 64. a sixth driven gear;

70. a planetary gear reduction mechanism.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it should be noted that, if terms indicating orientation or positional relationship such as "upper", "lower", "inside", "outside", etc. appear, they are based on the orientation or positional relationship shown in the drawings and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the appearances of the terms "first" to "sixth", and the like, if any, are also intended for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In addition, in the description of the present invention, the terms "mounted," "connected," and "connecting" are to be construed broadly unless otherwise specifically limited. For example, the connection can be fixed, detachable or integrated; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. To those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in conjunction with specific situations.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

Example one

The present embodiment relates to an electric drive axle, which comprises a plurality of electric motors, two output half shafts 60 connected by a differential 62, and a central shaft 40 sleeved on one output half shaft 60. Wherein, a first transmission mechanism is respectively arranged between each motor and the central shaft 40, and a second transmission mechanism and a third transmission mechanism are arranged between the central shaft 40 and the differential mechanism 62.

As shown in fig. 1, as a preferred embodiment, the present embodiment specifically uses two motors as an example to describe the structure of the electric drive axle. Each first transmission mechanism is provided with a first intermediate shaft 30 in transmission connection with the motor, a first gear shifting device 3 sleeved on the first intermediate shaft 30, and a first gear transmission unit and a second gear transmission unit which are arranged between the first gear shifting device 3 and the intermediate shaft 40 and have different transmission ratios. And the first gear shifting device 3 can alternatively be in driving connection with the central shaft 40 via the first gear transmission unit or the second gear transmission unit.

For the sake of convenience of description, in the present embodiment, with reference to the orientation shown in fig. 1, the upper motor in fig. 1 is referred to as a first motor 1, and the lower motor is referred to as a second motor 2. Meanwhile, as a preferred embodiment, the two first intermediate shafts 30, and the first motor 1 and the second motor 2 are arranged symmetrically with the central shaft 40 as a center.

In one embodiment, each motor is disposed coaxially with the first intermediate shaft 30 and is connected to one end of the first intermediate shaft 30. Still referring to fig. 1, the first intermediate shaft 30 arranged on the same side as the first electric motor 1 and the first motor output shaft 10 of the first electric motor 1 are arranged coaxially, and the first intermediate shaft 30 arranged on the same side as the second electric motor 2 and the second motor output shaft 13 of the second electric motor 2 are arranged coaxially. At the moment, the electric drive axle is suitable for heavy commercial vehicles with small wheel-side torque load requirements.

Of course, instead of the motor being arranged coaxially with the first intermediate shaft 30 as shown in fig. 1, the motor in this embodiment may be connected to the first intermediate shaft 30 via a first transmission gear set, as shown in fig. 2, offset to one side of the first intermediate shaft 30. At this time, the electric drive axle shown in fig. 2 has higher reliability and enhanced load bearing capacity, and is suitable for heavy and ultra-heavy commercial vehicles. For the sake of convenience of description, in the present embodiment, the electric drive axle in fig. 1 is referred to as a first structure, and the electric drive axle to which the first transmission gear set is added based on the first structure as shown in fig. 2 is referred to as a second structure.

In a second configuration, as shown in fig. 2, the first transmission gear set includes a fifth driving gear 11 provided on the motor, and a fifth driven gear 12 provided on the first intermediate shaft 30 and engaged with the fifth driving gear 11. The outer diameter of the fifth driving gear 11 is smaller than that of the fifth driven gear 12, and the first motor 1 and the second motor 2 drive the fifth driving gear 11 to rotate so as to drive the fifth driven gear 12 to transmit, thereby driving the first intermediate shaft 30 on the same side to rotate.

Still referring to fig. 1, in the transaxle of the present embodiment, the first gear transmission unit includes a first driving gear 31 provided at one side of the first gear shift device 3, and a first driven gear 41 provided on the central shaft 40 to be engaged with the first driving gear 31. The second gear transmission unit includes a second driving gear 32 provided at the other side of the first gear shift device 3, and a second driven gear 42 provided on the central shaft 40 to be engaged with the second driving gear 32.

The first gear shifting device 3 in this embodiment may adopt a two-way synchronizer in the prior art, which is mature in product and facilitates the connection of the first gear shifting device 3 with the central shaft 40 through the first gear transmission unit or the second gear transmission unit. And the transmission ratio of the first gear transmission unit and the second gear transmission unit is different, so that the adjustment of two different gears is facilitated.

As a preferred embodiment, still referring to fig. 1, two first gear transmission units share a first driven gear 41 and two second gear transmission units share a second driven gear 42. So set up, do benefit to and improve whole electric drive axle's integrated effect, and do benefit to reduction in production cost to do benefit to and reduce the volume of occuping to the car space.

It is understood that in the present embodiment, it is also possible to make only two first gear transmission units share one first driven gear 41, or to make only two second gear transmission units share one second driven gear 42. In this case, a good use effect can be achieved. There is no advantage in space occupation and cost, as compared with the scheme of sharing the first driven gear 41 and the second driven gear 42 at the same time.

Furthermore, it is also possible, but takes up more axial space, to have each first gear transmission unit comprise a first driving gear 31 and a first driven gear 41, which are separately provided, and to have each second gear transmission unit comprise a second driving gear 32 and a second driven gear 42, which are separately provided.

The second transmission mechanism in this embodiment has a second gear shift device 4 fitted around the central shaft 40, and a third gear transmission unit and a fourth gear transmission unit having different gear ratios are provided between the second gear shift device 4 and the differential 62. And the second shifting device 4 can alternatively be drivingly connected to the differential 62 via a third gear unit or a fourth gear unit.

And the third transmission mechanism has a third shifting device 5 which is sleeved on the central shaft 40. And the central shaft 40 can be directly drive-connected to the differential 62 by engagement of the third shifting device 5.

In this embodiment, the different gear ratios of the third and fourth gear units and the arrangement of the third shifting device 5 are beneficial to changing the torque transmitted to the differential 62, so as to change the gear of the output.

The second shifting device 4 also uses a prior art two-way synchronizer, and the third shifting device 5 uses a prior art one-way synchronizer. In particular use, the second shifting device 4 and the third shifting device 5 can only work with one being in neutral and the other being in neutral. During the shifting of the second shifting device 4 and the third shifting device 5, the dual-motor input power is cancelled, i.e., the torque transmission is interrupted during both shifting.

In the electric drive axle of the present exemplary embodiment, the first shifting device 3 can alternatively be in transmission connection with the central shaft 40 via the first gear transmission unit or the second gear transmission unit, the second shifting device 4 can alternatively be in transmission connection with the differential 62 via the third gear transmission unit or the fourth gear transmission unit, and the central shaft 40 can be in direct transmission connection with the differential 62 via the engagement of the third shifting device 5, so that the gear can be adjusted and different torques can be output.

Based on the overall description of the second transmission mechanism and the third transmission mechanism, still referring to fig. 1, a plurality of second intermediate shafts 50 are disposed radially outward of the central shaft 40, and each second intermediate shaft 50 is drivingly connected to the differential 62 through a second transmission gear set. The third gear transmission unit and the fourth gear transmission unit are in transmission connection with the differential 62 through a plurality of second intermediate shafts 50.

As an exemplary configuration, the third gear transmission unit includes a third driving gear 51 disposed on one side of the second gear shift device 4, and a third driven gear 55 disposed on each of the second countershafts 50 and engaged with the third driving gear 51. The fourth gear transmission unit includes a fourth driving gear 52 provided on the other side of the second gear shift device 4, and a fourth driven gear 56 provided on each of the second counter shafts 50 to be engaged with the fourth driving gear 52.

The second transmission gear set includes a sixth driven gear 64 connected to the differential 62, and sixth driving gears 54 respectively disposed on the second intermediate shafts 50, and each of the sixth driving gears 54 is engaged with the sixth driven gear 64. So configured, further adjustment of the torque transmitted to the differential 62 is facilitated.

In this embodiment, as a preferred embodiment, the second intermediate shaft 50 is also provided with two shafts distributed on both sides of the central shaft 40. The two second intermediate shafts 50 are symmetrically arranged on two opposite sides of the central shaft 40, and the two second intermediate shafts 50 are also arranged in one-to-one correspondence with the first intermediate shafts 30 in the two first transmission mechanisms and the central shaft 40. . As such, it can contribute to further improving the reliability of the drive axle in use.

The electric drive axle in this embodiment, under the prerequisite that satisfies the user demand, the specification of motor can be as little as possible to do benefit to the manufacturing cost who reduces electric drive axle, and can reduce the space occupation volume in the car.

Further, the electric drive axle of the present embodiment can be used for a vehicle type with a small wheel-side torque load demand when the structure shown in fig. 1 is employed. And when the electric drive axle adopts the structure shown in fig. 2, the torque requirements on the first motor 1 and the second motor 2 are favorably reduced, and the electric drive axle is suitable for vehicle types with higher bearing requirements.

In the electric drive axle of the present embodiment, transmission paths of the electric motors in different gears are substantially the same when in use, and the following description is given by taking the first structure shown in fig. 1 as an example, where the transmission path of the first electric motor 1 when in use is as follows:

when the first electric motor 1 is in the first gear, the first intermediate shaft 30 on the same side is driven to rotate by the first electric motor output shaft 10 of the first electric motor 1 under the driving of the first electric motor 1, the first gear shifting device 3 transmits torque to the central shaft 40 through the cooperation of the first driving gear 31 and the first driven gear 41, and then the second gear shifting device 4 transmits torque to the second intermediate shaft 50 on the same side through the cooperation of the third driving gear 51 and the third driven gear 55. At this time, the third shifting device 5 is in the neutral position, and the second intermediate shaft 50 transmits torque to the differential 62 through the engagement of the sixth driving gear 54 and the sixth driven gear 64, and transmits torque to both ends of the output half shaft 60 via the differential 62.

When the first electric motor 1 is in the second gear, the first intermediate shaft 30 on the same side is driven to rotate by the first electric motor output shaft 10 of the first electric motor 1 under the driving of the first electric motor 1, the first gear shifting device 3 transmits torque to the central shaft 40 through the cooperation of the second driving gear 32 and the second driven gear 42, and then the second gear shifting device 4 transmits torque to the second intermediate shaft 50 on the same side through the cooperation of the third driving gear 51 and the third driven gear 55. At this time, the third shifting device 5 is in the neutral position, and the second intermediate shaft 50 transmits torque to the differential 62 through the engagement of the sixth driving gear 54 and the sixth driven gear 64, and transmits torque to both ends of the output half shaft 60 via the differential 62.

When the first electric motor 1 is in the third gear, the first intermediate shaft 30 on the same side is driven to rotate by the first electric motor output shaft 10 of the first electric motor 1 under the driving of the first electric motor 1, the first gear shifting device 3 transmits torque to the central shaft 40 through the cooperation of the first driving gear 31 and the first driven gear 41, and then the second gear shifting device 4 transmits torque to the second intermediate shaft 50 on the same side through the cooperation of the fourth driving gear 52 and the fourth driven gear 56. At this time, the third shifting device 5 is in the neutral position, and the second intermediate shaft 50 transmits torque to the differential 62 through the engagement of the sixth driving gear 54 and the sixth driven gear 64, and transmits torque to both ends of the output half shaft 60 via the differential 62.

When the first electric motor 1 is in the fourth gear, the first intermediate shaft 30 on the same side is driven to rotate by the first electric motor output shaft 10 of the first electric motor 1 under the driving of the first electric motor 1, the first gear shifting device 3 transmits torque to the central shaft 40 through the cooperation of the second driving gear 32 and the second driven gear 42, and then the second gear shifting device 4 transmits torque to the second intermediate shaft 50 on the same side through the cooperation of the fourth driving gear 52 and the fourth driven gear 56. At this time, the third shifting device 5 is in the neutral position, and the second intermediate shaft 50 transmits torque to the differential 62 through the engagement of the sixth driving gear 54 and the sixth driven gear 64, and transmits torque to both ends of the output half shaft 60 via the differential 62.

When the first electric motor 1 is in the fifth gear, the first intermediate shaft 30 on the same side is driven to rotate by the first electric motor output shaft 10 of the first electric motor 1 under the driving of the first electric motor 1, and the first gear shifting device 3 transmits torque to the central shaft 40 through the cooperation of the first driving gear 31 and the first driven gear 41. At this time, the second shifting device 4 is in the neutral position, and the central shaft 40 transmits torque to the differential 62 through the third shifting device 5, and transmits torque to both ends of the output half shaft 60 via the differential 62.

When the first electric motor 1 is in the sixth gear, the first intermediate shaft 30 on the same side is driven to rotate by the first electric motor output shaft 10 of the first electric motor 1 under the driving of the first electric motor 1, and the first gear shifting device 3 transmits torque to the central shaft 40 through the cooperation of the second driving gear 32 and the second driven gear 42. At this time, the second shifting device 4 is in the neutral position, and the central shaft 40 transmits torque to the differential 62 through the third shifting device 5, and transmits torque to both ends of the output half shaft 60 via the differential 62.

The first electric machine 1 and the second electric machine 2 in this embodiment each have first to sixth gears, and a neutral gear when in use. In a specific use, the first motor 1 and the second motor 2 may operate synchronously, or only the first motor 1 or the second motor 2 operates. When the two motors work synchronously, the specific gear combination conditions of the first motor 1 and the second motor 2 in this embodiment are as follows:

when the first electric machine 1 is in the first gear and the second gear, the second electric machine 2 can be switched between the first gear, the second gear, or the neutral gear. When the first electric machine 1 is in the third gear and the fourth gear, the second electric machine 2 can be switched between the third gear, the fourth gear or neutral. When the first electric machine 1 is in the fifth gear and the sixth gear, the second electric machine 2 can be switched between the fifth gear, the sixth gear or neutral.

When the second electric machine 2 is in a different gear, the gear that the first electric machine 1 can adjust is just opposite to the corresponding gear of the first electric machine 1 and the second electric machine 2. In this embodiment, through setting up the bi-motor, can carry out the operation of shifting gears to another motor when one motor is in present fender position to can shift gears without break-off, do benefit to the smoothness that improves the shift gears, and the stability in the use.

In the embodiment, when the two motors are in the first gear to the sixth gear, the driving of large torque heavy load, medium load, low speed to medium speed can be realized. Under the working condition of low load requirement, one motor can be out of gear and stopped, and the other motor can be driven independently, so that the driving efficiency and the flexibility of use scenes during low load are improved.

In the present embodiment, it should be noted that the number of machines may be three, four or more arranged in the circumferential direction of the central shaft 40, instead of the two machines. When the motors with the number of three or more are adopted, the adjustable gears of the whole electric drive axle are more, and the adaptability is wider. Of course, in specific implementation, the number of the motors can be selected according to the use requirement, and the use requirement can be met. Preferably, when the number of the motors is more than two, each first gear transmission unit still can share one first driven gear 41, and each second gear transmission unit still shares one second driven gear 42, so that the first gear transmission unit and the second gear transmission unit are respectively connected with the central shaft 40 in a transmission way.

Of course, it is also possible that each first gear transmission unit is separately in transmission connection with the central shaft 40 via the first driven gear 41, and each second gear transmission unit is separately in transmission connection with the central shaft 40 via the second driven gear 42. However, this solution is more space-demanding to arrange and more costly to produce when implemented.

Further, it is noted that in this embodiment, the radial distances between the second intermediate shaft 50 and the first intermediate shaft 30 and the central shaft 40 are made the same. It is of course also possible to make the radial distance between the second intermediate shaft 50 and the first intermediate shaft 30 and the central shaft 40 different, so that both are parallel to each other but staggered with respect to each other. In the various configurations of the present embodiment shown in fig. 1 and 2, the differential 62 is specifically disposed at one end of the electric drive axle, and the motors are disposed at the other end of the electric drive axle with respect to the differential 62.

Example two

The present embodiment also relates to an electric drive axle having substantially the same structure as the electric drive axle in the first embodiment, except that, as shown in fig. 3, the motor is described by taking two specific examples.

In the present embodiment, each motor is connected to the first intermediate shaft 30 through a first transmission gear set, and is offset to one side of the first intermediate shaft 30. The second intermediate shaft 50 and the first intermediate shaft 30 are arranged in parallel and staggered radially outward between the center shafts 40, the motors are also arranged in parallel and staggered radially outward of the center shafts 40 with the second intermediate shaft 50, and the motors are also arranged close to the differential 62.

It is to be understood that the arrangement of the electric drive axle in fig. 3 is a modification of the second structure of the embodiment. Also, referring still to fig. 3, as described above, the main difference of the structure shown in the present embodiment is that the first intermediate shaft 30 and the second intermediate shaft 50 are arranged in parallel and staggered in the radial direction outside of the central shaft 40, and each motor is arranged in parallel and staggered in the radial direction outside of the central shaft 40 with the second intermediate shaft 50, and specifically, the second intermediate shaft 50 and the motors are arranged in a nested manner inside and outside in the radial direction of the central shaft 40.

The structural arrangement mode of the embodiment can fully utilize the radial outer space of the central shaft 40, and greatly reduce the radial dimension of the central shaft 40 of the electric drive axle. The length of the whole electric drive axle in the axial direction is further reduced, and arrangement and implementation in a vehicle are further facilitated. The electric drive axle of the design shown in fig. 3 can be used on medium-heavy trucks.

In addition, in the present embodiment, as one of the implementation forms, a planetary gear reduction mechanism 70 may be provided on two output half shafts 60, and the planetary gear reduction mechanism 70 may be a fixed-speed-ratio reduction mechanism, so that each output half shaft 60 is in transmission connection with a wheel through the fixed-speed-ratio planetary gear reduction mechanism 70. The planetary gear reduction mechanism 70 in this embodiment may adopt a mature planetary gear reduction structure in the prior art, and has the advantages of mature product, small volume occupation, high transmission efficiency, and the like.

The electric drive axle in the embodiment can effectively reduce the rotating speed and increase the torque by arranging the planetary gear speed reducing mechanism 70, thereby improving the transmission efficiency.

In a specific structure, as shown in fig. 4, the electric transaxle is shown based on the structure shown in fig. 3, with the addition of a planetary gear reduction mechanism 70. In this case, the electric drive axle of the configuration shown in fig. 4 can be used in a heavy truck for better driving effect and stability in use.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. An electric drive axle, characterized by: including a plurality of motors, two output half shafts (60) that are linked together by differential (62), and the center pin (40) of cover setting on one of them output half shaft (60), wherein:

a first transmission mechanism is arranged between each motor and the central shaft (40), and a second transmission mechanism and a third transmission mechanism are arranged between the central shaft (40) and the differential mechanism (62);

each first transmission mechanism is provided with a first intermediate shaft (30) in transmission connection with the motor, a first gear shifting device (3) sleeved on the first intermediate shaft (30), and a first gear transmission unit and a second gear transmission unit which are arranged between the first gear shifting device (3) and the central shaft (40) and have different transmission ratios, and the first gear shifting device (3) can be alternatively in transmission connection with the central shaft (40) through the first gear transmission unit or the second gear transmission unit;

the second transmission mechanism is provided with a second gear shifting device (4) sleeved on the central shaft (40), a third gear transmission unit and a fourth gear transmission unit with different transmission ratios are arranged between the second gear shifting device (4) and the differential mechanism (62), and the second gear shifting device (4) can be alternatively in transmission connection with the differential mechanism (62) through the third gear transmission unit or the fourth gear transmission unit;

the third transmission mechanism is provided with a third gear shifting device (5) sleeved on the central shaft (40), and the central shaft (40) can be directly connected with the differential (62) in a transmission mode through the engagement of the third gear shifting device (5).

2. The electric drive axle of claim 1, wherein:

the first gear transmission unit comprises a first driving gear (31) arranged on one side of the first gear shifting device (3) and a first driven gear (41) arranged on the central shaft (40) and meshed with the first driving gear (31);

the second gear transmission unit comprises a second driving gear (32) arranged on the other side of the first gear shifting device (3) and a second driven gear (42) arranged on the central shaft (40) and meshed with the second driving gear (32);

-one first driven gear (41) is common to each first gear transmission unit, and/or-one second driven gear (42) is common to each second gear transmission unit.

3. The electric drive axle of claim 1, wherein:

a plurality of second intermediate shafts (50) are arranged on the radial outer side of the central shaft (40), and the second intermediate shafts (50) are in transmission connection with the differential (62) through a second transmission gear set;

the third gear transmission unit and the fourth gear transmission unit are in transmission connection with the differential (62) through a plurality of second intermediate shafts (50).

4. The electric drive axle of claim 3, wherein:

the third gear transmission unit comprises a third driving gear (51) arranged on one side of the second gear shifting device (4) and a third driven gear (55) arranged on each second intermediate shaft (50) and meshed with the third driving gear (51);

the fourth gear transmission unit includes a fourth driving gear (52) provided on the other side of the second gear shift device (4), and a fourth driven gear (56) provided on each of the second countershafts (50) to be engaged with the fourth driving gear (52).

5. The electric drive axle of claim 3, wherein:

the second transmission gear set comprises a sixth driven gear (64) connected to the differential (62), and sixth driving gears (54) respectively arranged on the second intermediate shafts (50), and each sixth driving gear (54) is meshed with the sixth driven gear (64).

6. The electric drive axle of claim 3, wherein:

the motor is arranged coaxially with the first intermediate shaft (30) and is connected to one end of the first intermediate shaft (30); alternatively, the electric motor is connected to the first intermediate shaft (30) via a first transmission gear set, offset to one side of the first intermediate shaft (30).

7. The electric drive axle of claim 6, wherein:

the radial distances between the second intermediate shaft (50) and the first intermediate shaft (30) and the central shaft (40) are the same or different, the differential (62) is arranged at one end of the electric drive axle, and each motor is arranged at the other end of the electric drive axle relative to the differential (62).

8. The electric drive axle of claim 3, wherein:

the motor is connected with the first intermediate shaft (30) through a first transmission gear set and is offset on one side of the first intermediate shaft (30);

the second intermediate shaft (50) and the first intermediate shaft (30) are arranged in parallel and staggered on the radial outer side of the central shaft (40), the motor and the second intermediate shaft (50) are arranged in parallel and staggered on the radial outer side of the central shaft (40), and the motor is arranged close to the differential (62).

9. The electric drive axle of claim 8, wherein:

the two output half shafts (60) are respectively provided with a planetary gear speed reducing mechanism (70), and each output shaft (60) is in transmission connection with a wheel through the planetary gear speed reducing mechanism (70).

10. Electric drive axle according to claim 6 or 8, characterized in that:

the first transmission gear set comprises a fifth driving gear (11) arranged on the motor and a fifth driven gear (12) arranged on the first intermediate shaft (30) and meshed with the fifth driving gear (11), and the outer diameter of the fifth driving gear (11) is smaller than that of the fifth driven gear (12).