Multi-gear transmission electric drive axle system

Abstract

The utility model relates to a multi-gear transmission electric drive axle system which comprises a first motor, a second motor, a first gear shifting mechanism, a second gear shifting mechanism, a third gear shifting mechanism, a planetary gear train and a differential mechanism assembly, and the differential mechanism assembly finally outputs power to wheel ends through an output shaft. In the system, a first motor and a second motor are arranged on the two sides of an output shaft respectively, the first motor, a first gear shifting mechanism, a planetary gear train and a differential assembly are sequentially in transmission connection, and the second motor, a second gear shifting mechanism, a third gear shifting mechanism, the planetary gear train and the differential assembly are sequentially in transmission connection; the first motor and the second motor provide power for the system, and the first gear shifting mechanism, the second gear shifting mechanism and the third gear shifting mechanism can achieve torque adjustment and conversion of at most eight gears by changing the meshing transmission relation of the first gear shifting mechanism, the second gear shifting mechanism and the third gear shifting mechanism.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle power systems, and in particular to a multi-speed transmission electric drive axle system suitable for a pure electric-driven heavy-duty commercial vehicle. Background Art

[0002] At present, pure electric heavy-duty commercial trucks mostly use two driving methods: central electric drive and electric drive axle to achieve vehicle power transmission. Among them, central electric drive means that the motor directly drives the vehicle's drive shaft or transmission system. There is usually only one large motor located in the center of the vehicle chassis, while the electric drive axle integrates the motor into the vehicle's wheel hub or axle, and realizes power distribution and vehicle stability control by individually controlling each motor.

[0003] Since electric drive axles have the advantage of smaller installation space, they have greater development potential. Taking dual-motor electric drive axles as an example, their layout is mostly dual-motor plus planetary gear arrangement, but only one motor is used as the main drive motor, and the other motor is used as an auxiliary torque-increasing motor, and most of them are arranged in two or three gears.

[0004] In an existing dual-motor electric drive axle system, power is transmitted from the motor to the differential by symmetrically arranging three-stage parallel shafts on both sides, and two gears are set on the second-stage parallel shaft on each side. However, this system only realizes the arrangement and switching of two gears on the second stage on one side, and there is no gear on the other side. The vehicle has few gears and cannot take into account the transmission requirements of high speed ratio at low speed and small speed ratio at high speed. Moreover, when the gears on both sides are inconsistent, it is difficult to take into account the speed of each motor in the optimal efficiency range of the motor. Utility Model Content

[0005] The utility model discloses a multi-speed transmission electric drive axle system, aiming to solve the technical problems existing in the prior art.

[0006] The utility model adopts the following technical solutions:

[0007] The embodiment of the utility model provides a multi-speed transmission electric drive axle system, including a first motor, a second motor, a first shift mechanism, a second shift mechanism, a third shift mechanism, a planetary gear train and a differential assembly;

[0008] The first motor, the first shift mechanism, the planetary gear train and the differential assembly are sequentially connected in transmission;

[0009] The first shifting mechanism comprises a first sliding sleeve, a first driving gear and a first driven gear meshing with each other, a second driving gear and a second driven gear meshing with each other, and the first sliding sleeve can be selectively connected to the first driving gear or the second driving gear in transmission;

[0010] The second motor, the second shift mechanism, the third shift mechanism, the planetary gear train and the differential assembly are sequentially connected in transmission;

[0011] The second shift mechanism comprises a second sliding sleeve, a third driving gear and a fourth driving gear, the third driving gear and the fourth driving gear are both drivingly connected to the second motor, and the second sliding sleeve can be selectively drivingly connected to the third driving gear or the fourth driving gear;

[0012] The third shifting mechanism comprises a third sliding sleeve, a fifth driving gear and a sixth driving gear. The third sliding sleeve can be selectively connected to the fifth driving gear or the sixth driving gear. The fifth driving gear meshes with the first driven gear, and the sixth driving gear meshes with the second driven gear.

[0013] As a preferred technical solution, the planetary gear train includes a sun gear, planetary gears, an inner ring gear and a planet carrier, the inner ring gear is fixedly connected to the housing, the planet carrier is fixedly connected to the differential assembly, and the sun gear is fixedly connected to the first driven gear and the second driven gear.

[0014] As a preferred technical solution, the first motor includes a first input gear, and the first shift mechanism also includes a first constant mesh gear, and the first constant mesh gear is respectively transmission-connected to the first input gear and the first sleeve.

[0015] As a preferred technical solution, the second motor includes a second input gear and a third input gear arranged coaxially, the third driving gear is transmission-connected to the second input gear, and the fourth driving gear is transmission-connected to the third input gear;

[0016] The second shifting mechanism further includes a second constantly meshing gear, and the third shifting mechanism further includes a third constantly meshing gear. The second constantly meshing gear meshes with the third constantly meshing gear.

[0017] As a preferred technical solution, the transmission ratios of the first input gear and its meshing gear, the second input gear and its meshing gear, the third input gear and its meshing gear, the first driving gear and its meshing gear, the second driving gear and its meshing gear, and the second constant meshing gear and its meshing gear are different.

[0018] As a preferred technical solution, when in the first gear transmission state, the first sliding sleeve is transmission-connected to the first driving gear, the second sliding sleeve is transmission-connected to the third driving gear, and the third sliding sleeve is transmission-connected to the fifth driving gear.

[0019] As a preferred technical solution, when in the second gear transmission state, the first sliding sleeve is transmission-connected to the first driving gear, the second sliding sleeve is transmission-connected to the third driving gear, and the third sliding sleeve is transmission-connected to the sixth driving gear.

[0020] As a preferred technical solution, when in the third gear transmission state, the first sliding sleeve is transmission-connected to the first driving gear, the second sliding sleeve is transmission-connected to the fourth driving gear, and the third sliding sleeve is transmission-connected to the fifth driving gear.

[0021] As a preferred technical solution, when in the fourth gear transmission state, the first sliding sleeve is transmission-connected to the second driving gear, the second sliding sleeve is transmission-connected to the fourth driving gear, and the third sliding sleeve is transmission-connected to the fifth driving gear.

[0022] As a preferred technical solution, when in the fifth gear transmission state, the first sliding sleeve is transmission-connected to the second driving gear, the second sliding sleeve is transmission-connected to the fourth driving gear, and the third sliding sleeve is transmission-connected to the sixth driving gear.

[0023] One embodiment of the above utility model has the following advantages or beneficial effects:

[0024] The utility model mainly provides a multi-speed transmission electric drive axle system, which is suitable for pure electric drive heavy-duty commercial trucks. Compared with the prior art, the electric drive axle system of the utility model provides three sets of shifting mechanisms, which are respectively realized by the first sliding sleeve, the second sliding sleeve and the third sliding sleeve selectively connected to the corresponding gears or housing transmission. Through the combination of these three sets of shifting mechanisms, up to eight gear changes can be realized, and five of the gears are selected as the shifting gears in actual use based on actual operation, which can meet the different working conditions from low speed and high torque to high speed and small torque, and can make the motor operate in a high efficiency range under a wider range of vehicle speed conditions, thereby improving the energy utilization efficiency of the whole vehicle.

[0025] This system only uses a three-stage or four-stage transmission structure, and the configuration is relatively simple and compact. Compared with the traditional electric drive axle multi-stage transmission structure, the overall transmission link is shorter, reducing transmission losses. At the same time, this system uses a planetary reducer structure with high transmission efficiency, and uses the planetary reducer as the final reduction stage. The planetary carrier is connected to the differential assembly, and the feedback torque of the planetary system can be reasonably distributed to the two wheels, which is beneficial to vehicle stability control.

[0026] Furthermore, the two motors are connected to the planetary gear train through different shifting mechanism combinations, which can flexibly distribute power output according to demand and improve control performance; the three shifting mechanisms control the input of the two motors respectively, independently of each other, and can control each motor and its shifting separately. Shifting will not affect the power output of another motor, thereby ensuring the continuity and stability of the power output of the whole vehicle.

[0027] In addition, the system is highly modular, and each component can be replaced or upgraded independently, which is conducive to standardized production and maintenance, and improves applicability and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solution of the embodiment of the utility model, the following is a brief introduction to the drawings required for the description of the embodiment, which constitute a part of the utility model. The schematic embodiment of the utility model and its description explain the utility model and do not constitute an improper limitation of the utility model. In the drawings:

[0029] Figure 1 This is a schematic structural diagram of a multi-speed transmission electric drive axle system disclosed in Embodiment 1 of the present utility model;

[0030] Figure 2 This is a schematic structural diagram of a planetary gear train disclosed in Example 1 of the utility model;

[0031] Figure 3 This is a schematic diagram of power flow of the multi-speed transmission electric drive axle system disclosed in Example 1 of the utility model when transmitting in the first gear;

[0032] Figure 4 It is a schematic diagram of power flow of the multi-speed transmission electric drive axle system disclosed in Embodiment 1 of the utility model during second-speed transmission;

[0033] Figure 5 It is a schematic diagram of power flow of the multi-speed transmission electric drive axle system disclosed in Embodiment 1 of the utility model during third-speed transmission;

[0034] Figure 6 It is a schematic diagram of power flow of the multi-speed transmission electric drive axle system disclosed in Embodiment 1 of the utility model during fourth-speed transmission;

[0035] Figure 7 This is a schematic diagram of the power flow of the multi-speed transmission electric drive axle system disclosed in Example 1 of the utility model when transmitting in fifth gear.

[0036] Description of reference numerals:

[0037] A first motor 11, a first input gear 12; a first constant mesh gear 21, a first sleeve 22, a first driving gear 23, a second driving gear 24, a first driven gear 25, a second driven gear 26; a second motor 31, a second input gear 32, a third input gear 33; a third driving gear 41, a fourth driving gear 42, a second sleeve 43, a second constant mesh gear 44; a third constant mesh gear 51, a third sleeve 52, a fifth driving gear 53, a sixth driving gear 54; a planetary gear train 6, a sun gear 61, a planetary gear 62, a planet carrier 63, an inner ring gear 64; a differential assembly 7, a first output half shaft 81, a second output half shaft 82; a wheel end 91. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be clearly and completely described below in combination with the specific embodiments of the utility model and the corresponding drawings. In the description of the utility model, it should be noted that the term "or" is usually used in the sense of including "and / or", unless the content clearly indicates otherwise.

[0039] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a magnetic connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be internal communication between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. In addition, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0040] Obviously, the described embodiments are only some embodiments of the utility model, not all embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0041] Example 1

[0042] refer to Figure 1 , Figure 2 The embodiment of the utility model provides a multi-speed transmission electric drive axle system. By setting two motors and three sets of shifting mechanisms, it can meet the different working conditions from low speed and high torque to high speed and small torque. It can make the motor operate in a high efficiency range under a wider range of vehicle speed conditions, thereby improving the energy utilization efficiency of the whole vehicle.

[0043] In a preferred embodiment, the multi-speed transmission electric drive bridge system includes a first motor 11, a second motor 31, a first shifting mechanism, a second shifting mechanism, a third shifting mechanism, a planetary gear train 6 and a differential assembly 7, and the differential assembly 7 finally outputs the power to the wheel end 91 through the output shaft; in the system, the first motor 11 and the second motor 31 are respectively arranged on both sides of the output shaft, the first motor 11, the first shifting mechanism, the planetary gear train 6 and the differential assembly 7 are sequentially connected in transmission, and the second motor 31, the second shifting mechanism, the third shifting mechanism, the planetary gear train 6 and the differential assembly 7 are sequentially connected in transmission; the first motor 11 and the second motor 31 provide power for the system respectively, and the first shifting mechanism, the second shifting mechanism and the third shifting mechanism can realize torque adjustment and the transformation of up to eight gears by changing their own meshing transmission relationship.

[0044] In a preferred embodiment, the input shaft of the first motor 11 is fixedly connected to the first input gear 12 by a spline, and the first input gear 12 is used to transmit the torque generated by the first motor 11 to the first gear shifting mechanism; the input shaft of the second motor 31 is fixedly connected to the second input gear 32 and the third input gear 33 by a spline, and the second input gear 32 or the third input gear 33 is used to transmit the torque generated by the second motor 31 to the second gear shifting mechanism and the third gear shifting mechanism in sequence; preferably, the transmission ratios of the first input gear 12 and its meshing gears, the second input gear 32 and its meshing gears, and the third input gear 33 and its meshing gears are different. In this embodiment, the transmission ratio is the reduction ratio.

[0045] Preferably, the first motor 11 and the second motor 31 have the same specifications, and their structures both include a stator, a coil, a rotor and an input shaft. In this embodiment, the specific model, structure or specification of the first motor 11 / the second motor 31 is no longer limited, and technicians in this field can freely choose according to actual needs.

[0046] In a preferred embodiment, the first shifting mechanism includes a first constantly meshed gear 21, a first sleeve 22, a first driving gear 23 and a first driven gear 25 meshing therewith, a second driving gear 24 and a second driven gear 26 meshing therewith, wherein the first constantly meshed gear 21, the first driving gear 23 and the second driving gear 24 are coaxially arranged, the first constantly meshed gear 21 is respectively transmission-connected to the first input gear 12 and the first sleeve 22, and the first sleeve 22 can be selectively transmission-connected to the first driving gear 23 or the second driving gear 24.

[0047] Preferably, the first driving gear 23 and the second driving gear 24 have different reduction ratios, and more preferably, the reduction ratio of the first driven gear 25 to the first driving gear 23 is greater than the reduction ratio of the second driven gear 26 to the second driving gear 24. Those skilled in the art should understand that the greater the reduction ratio, the greater the output torque, that is, when the first sleeve 22 is connected to the first driving gear 23 in transmission, its reduction ratio is greater than the reduction ratio when the first sleeve 22 is connected to the second driving gear 24, at which time the torque is large and the gear is low. Specifically, in this embodiment, the specific ratio of the reduction ratio and the number of teeth of each transmission tooth are no longer limited, and those skilled in the art can make adaptive adjustments according to actual application scenarios.

[0048] Preferably, the reduction ratios of the first driven gear 25 and the first driving gear 23 , the reduction ratios of the second driven gear 26 and the second driving gear 24 , and the reduction ratios of the first constant meshing gear 21 and the first input gear 12 are different.

[0049] In a preferred embodiment, the second shifting mechanism includes a coaxially arranged second sleeve 43, a third driving gear 41 and a fourth driving gear 42, the third driving gear 41 is transmission connected to the second input gear 32, the fourth driving gear 42 is transmission connected to the third input gear 33, and the second sleeve 43 can be selectively transmission connected to the third driving gear 41 or the fourth driving gear 42.

[0050] Preferably, the reduction ratio between the third driving gear 41 and the second input gear 32 is greater than the reduction ratio between the fourth driving gear 42 and the third input gear 33, that is, when the second sleeve 43 is connected to the third driving gear 41, the torque output by the second shifting mechanism is greater than the torque output when the second sleeve 43 is connected to the fourth driving gear 42.

[0051] Furthermore, the second shifting mechanism also includes a second constant meshing gear 44, which is coaxially arranged with the third driving gear 41 and the fourth driving gear 42; the third shifting mechanism includes a coaxially arranged third sliding sleeve 52, a third constant meshing gear 51, a fifth driving gear 53 and a sixth driving gear 54, and the second constant meshing gear 44 is meshed with the third constant meshing gear 51.

[0052] Preferably, the fifth driving gear 53 is meshed with the first driven gear 25, the sixth driving gear 54 is meshed with the second driven gear 26, and the third sleeve 52 is selectively transmission-connected with the fifth driving gear 53 or the sixth driving gear 54; preferably, the reduction ratio of the first driven gear 25 to the fifth driving gear 53 is greater than the reduction ratio of the second driven gear 26 to the sixth driving gear 54.

[0053] In a preferred embodiment, the reduction ratio of the first driven gear 25 and the fifth driving gear 53 is equal to the reduction ratio of the first driven gear 25 and the first driving gear 23, and the reduction ratio of the second driven gear 26 and the sixth driving gear 54 is equal to the reduction ratio of the second driven gear 26 and the second driving gear 24; preferably, the specifications of the fifth driving gear 53 are the same as those of the first driving gear 23, and the specifications of the sixth driving gear 54 are the same as those of the second driving gear 24; the third shifting mechanism and the first shifting mechanism are symmetrically arranged on both sides of the output shaft.

[0054] In a preferred embodiment, the reduction ratio of the first constant mesh gear 21 and the first input gear 12, the reduction ratio of the third driving gear 41 and the second input gear 32, the reduction ratio of the fourth driving gear 42 and the third input gear 33, the reduction ratio of the first driven gear 25 and the first driving gear 23 / the fifth driving gear 53, the reduction ratio of the second driven gear 26 and the second driving gear 24 / the sixth driving gear 54, and the reduction ratio of the third constant mesh gear 51 and the second constant mesh gear 44 are different, so that the system can provide greater torque at low speed and improve transmission efficiency at high speed to reduce energy loss. In addition, different reduction ratio settings can ensure that the motor can operate in its optimal efficiency range at different speeds and loads to improve the energy utilization of the system.

[0055] Preferably, the planetary gear train 6 includes a sun gear 61 , planetary gears 62 , a planet carrier 63 and an inner ring gear 64 , wherein the inner ring gear 64 is engaged with the housing, the planet carrier 63 is engaged with the differential assembly 7 , and the sun gear 61 is engaged with the first driven gear 25 and the second driven gear 26 .

[0056] In a preferred embodiment, the sun gear 61 is arranged in the middle of the planetary gear 62, and the sun gear 61 can mesh with the inner gear ring 64 through the planetary gear 62; the planetary gear 62 is arranged around the sun gear 61, and its inner side meshes with the sun gear 61, and its outer side meshes with the inner gear ring 64, and is connected to the planetary carrier 63 through rollers or bearings. There can be multiple planetary gears 62, which are evenly distributed around the planetary carrier 63; the planetary carrier 63 is a supporting structure connected to the planetary gear 62, and there are multiple holes on the planetary carrier 63, and a planetary gear 62 is installed in each hole to support the planetary gear 62 and ensure its normal movement. By changing the meshing relationship of each component in the planetary gear system 6, its relative operating relationship can be changed to achieve output of different speed ratios and torques, and examples are not listed one by one here.

[0057] Specifically, the specific structure of the planetary gear train 6 can be any embodiment disclosed in the prior art, and its structure is not specifically limited in this patent.

[0058] Preferably, the output ends of the differential assembly 7 are respectively connected to the first output half shaft 81 and the second output half shaft 82 , which are respectively connected to the wheel end 91 , so as to ultimately transmit the power from the first motor 11 and the second motor 31 to the wheel end 91 .

[0059] In the above system, by selectively connecting the first sleeve 22, the second sleeve 43 and the third sleeve 52 with the corresponding gear transmission, a maximum of eight gear changes can be achieved. However, in actual driving, not all eight gears are required to cover the entire speed range. Therefore, in this embodiment, only five most representative gears are selected to meet the power requirements in most driving situations, so as to improve the overall efficiency and reliability of the system, avoid the negative impact of frequent gear shifting on the driving experience, reduce unnecessary complexity, and simplify operations during driving.

[0060] In a preferred embodiment, when the first sleeve 22 is transmission connected to the first driving gear 23 with a larger reduction ratio, the second sleeve 43 is transmission connected to the third driving gear 41 with a larger reduction ratio, and the third sleeve 52 is transmission connected to the fifth driving gear 53 with a larger reduction ratio, the system can achieve a first gear transmission state.

[0061] like Figure 3 , the red color in the figure indicates the power flow direction; in the first gear transmission state, the power is input by the first motor 11 and the second motor 31, and is transmitted to the first constant mesh gear 21 and the third driving gear 41 by the first input gear 12 and the second input gear 32 respectively. The third driving gear 41 is fixedly connected to the second constant mesh gear 44, and then transmitted to the third constant mesh gear 51 by the second constant mesh gear 44, and then transmitted to the first driven gear 25 by the first driving gear 23 and the fifth driving gear 53 respectively, and then transmitted to the planetary gear 62 through the sun gear 61 in the planetary gear train 6, and transmitted to the differential assembly 7 through the planet carrier 63, and finally transmitted to the wheel end 91 by the first output half shaft 81 and the second output half shaft 82 respectively, so as to realize the power transmission of four-stage deceleration and torque increase.

[0062] In a preferred embodiment, when the first sleeve 22 is transmission connected to the first driving gear 23 with a larger reduction ratio, the second sleeve 43 is transmission connected to the third driving gear 41 with a larger reduction ratio, and the third sleeve 52 is transmission connected to the sixth driving gear 54 with a smaller reduction ratio, the system can achieve a second gear transmission state.

[0063] like Figure 4, the red color in the figure indicates the power flow direction; in the second gear transmission state, the power is input by the first motor 11 and the second motor 31, and is transmitted to the first constant mesh gear 21 and the third driving gear 41 by the first input gear 12 and the second input gear 32 respectively. The third driving gear 41 is fixedly connected to the second constant mesh gear 44, and then transmitted to the third constant mesh gear 51 by the second constant mesh gear 44, and then transmitted to the first driven gear 25 and the second driven gear 26 by the first driving gear 23 and the sixth driving gear 54 respectively, and then transmitted to the planetary gear 62 through the sun gear 61 in the planetary gear train 6, and transmitted to the differential assembly 7 through the planet carrier 63, and finally transmitted to the wheel end 91 by the first output half shaft 81 and the second output half shaft 82 respectively, so as to realize the power transmission of four-stage deceleration and torque increase.

[0064] In a preferred embodiment, when the first sleeve 22 is transmission connected to the first driving gear 23 with a larger reduction ratio, the second sleeve 43 is transmission connected to the fourth driving gear 42 with a smaller reduction ratio, and the third sleeve 52 is transmission connected to the fifth driving gear 53 with a larger reduction ratio, the system can achieve a third gear transmission state.

[0065] like Figure 5 , the red color in the figure indicates the power flow direction; in the third gear transmission state, the power is input by the first motor 11 and the second motor 31, and is transmitted to the first constant mesh gear 21 and the fourth driving gear 42 by the first input gear 12 and the third input gear 33 respectively. The fourth driving gear 42 is fixedly connected to the second constant mesh gear 44, and then transmitted to the third constant mesh gear 51 by the second constant mesh gear 44, and then transmitted to the first driven gear 25 by the first driving gear 23 and the fifth driving gear 53 respectively, and then transmitted to the planetary gear 62 through the sun gear 61 in the planetary gear train 6, and transmitted to the differential assembly 7 through the planetary carrier 63, and finally transmitted to the wheel end 91 by the first output half shaft 81 and the second output half shaft 82 respectively, so as to realize the power transmission of four-stage deceleration and torque increase.

[0066] In a preferred embodiment, when the first sleeve 22 is transmission connected to the second driving gear 24 with a smaller reduction ratio, the second sleeve 43 is transmission connected to the fourth driving gear 42 with a smaller reduction ratio, and the third sleeve 52 is transmission connected to the fifth driving gear 53 with a larger reduction ratio, the system can achieve a fourth gear transmission state.

[0067] like Figure 6, the red color in the figure indicates the power flow direction; in the fourth gear transmission state, the power is input by the first motor 11 and the second motor 31, and is transmitted to the first constant mesh gear 21 and the fourth driving gear 42 by the first input gear 12 and the third input gear 33 respectively. The fourth driving gear 42 is fixedly connected to the second constant mesh gear 44, and then transmitted to the third constant mesh gear 51 by the second constant mesh gear 44, and then transmitted to the second driven gear 26 and the first driven gear 25 by the second driving gear 24 and the fifth driving gear 53 respectively, and then transmitted to the planetary gear 62 through the sun gear 61 in the planetary gear train 6, and transmitted to the differential assembly 7 through the planetary carrier 63, and finally transmitted to the wheel end 91 by the first output half shaft 81 and the second output half shaft 82 respectively, so as to realize the power transmission of four-stage deceleration and torque increase.

[0068] In a preferred embodiment, when the first sleeve 22 is transmission connected to the second driving gear 24 with a smaller reduction ratio, the second sleeve 43 is transmission connected to the fourth driving gear 42 with a smaller reduction ratio, and the third sleeve 52 is transmission connected to the sixth driving gear 54 with a smaller reduction ratio, the system can achieve a five-speed transmission state.

[0069] like Figure 7 , the red color in the figure indicates the power flow direction; in the fifth gear transmission state, the power is input by the first motor 11 and the second motor 31, and is transmitted to the first constant mesh gear 21 and the fourth driving gear 42 by the first input gear 12 and the third input gear 33 respectively, the fourth driving gear 42 is fixedly connected to the second constant mesh gear 44, and then transmitted to the third constant mesh gear 51 by the second constant mesh gear 44, and then transmitted to the second driven gear 26 by the second driving gear 24 and the sixth driving gear 54 respectively, and then transmitted to the planetary gear 62 through the sun gear 61 in the planetary gear train 6, and transmitted to the differential assembly 7 through the planet carrier 63, and finally transmitted to the wheel end 91 by the first output half shaft 81 and the second output half shaft 82 respectively, so as to realize the power transmission of four-stage deceleration and torque increase.

[0070] Compared with the prior art, the multi-speed transmission electric drive axle system provided in this embodiment has a simple configuration, fewer shaft systems, smoother gear power flow planning, and fewer transmission levels, such as three or four levels, while ensuring the number of gears. It has a large designed torque capacity, convenient power control, and a more modular layout. It can take into account the vehicle's high torque requirements in low gears and high speed requirements in high gears, while ensuring that the motor is in the optimal efficiency speed range.

[0071] Example 2

[0072] The present embodiment provides a vehicle, preferably a heavy-duty commercial truck with pure electric drive, including the multi-speed transmission electric drive axle system described in the above-mentioned embodiment 1. The technical features recorded in the above-mentioned embodiment 1 are naturally inherited in the present embodiment; specifically, in the present embodiment, the vehicle equipped with the multi-speed transmission electric drive axle system has the same functions as the above-mentioned embodiment 1, so they will not be described one by one.

[0073] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application to this. Those of ordinary skill in the art may make various changes and modifications therein without departing from the scope and spirit of the present application. All these changes and modifications are intended to be included within the scope of the present application as required by the appended claims.

[0074] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0075] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various utility model aspects, in the description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present application should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the corresponding claims, its utility model point is that the corresponding technical problem can be solved with less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are hereby explicitly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0076] It will be understood by those skilled in the art that, except for mutually exclusive features, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this specification may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature that provides the same, equivalent or similar purpose.

Claims

1. A multi-speed transmission electric drive axle system, characterized in that: It includes a first motor, a second motor, a first shift mechanism, a second shift mechanism, a third shift mechanism, a planetary gear train and a differential assembly; The first motor, the first shift mechanism, the planetary gear train and the differential assembly are sequentially connected in transmission; The first shift mechanism comprises a first sliding sleeve, a first driving gear and a first driven gear meshing with each other, and a second driving gear and a second driven gear meshing with each other, and the first sliding sleeve can be selectively connected to the first driving gear or the second driving gear in driving connection; The second motor, the second shift mechanism, the third shift mechanism, the planetary gear train and the differential assembly are sequentially connected in transmission; The second shift mechanism comprises a second sliding sleeve, a third driving gear and a fourth driving gear, the third driving gear and the fourth driving gear are both drivingly connected to the second motor, and the second sliding sleeve can be selectively drivingly connected to the third driving gear or the fourth driving gear; The third shifting mechanism comprises a third sliding sleeve, a fifth driving gear and a sixth driving gear. The third sliding sleeve can be selectively connected to the fifth driving gear or the sixth driving gear in driving connection. The fifth driving gear is meshed with the first driven gear, and the sixth driving gear is meshed with the second driven gear.

2. The multi-speed transmission electric drive axle system according to claim 1, characterized in that: The planetary gear system includes a sun gear, planetary gears, an inner gear ring and a planet carrier. The inner gear ring is fixedly connected to the housing, the planet carrier is fixedly connected to the differential assembly, and the sun gear is transmission-fixedly connected to the first driven gear and the second driven gear.

3. The multi-speed transmission electric drive axle system according to claim 1, characterized in that: The first motor includes a first input gear, and the first shifting mechanism also includes a first constant meshing gear, which is respectively transmission-connected to the first input gear and the first sliding sleeve.

4. The multi-speed transmission electric drive axle system according to claim 3, characterized in that: The second motor comprises a second input gear and a third input gear which are coaxially arranged, the third driving gear is transmission-connected with the second input gear, and the fourth driving gear is transmission-connected with the third input gear; The second shift mechanism further includes a second constantly meshed gear, and the third shift mechanism further includes a third constantly meshed gear. The second constantly meshed gear meshes with the third constantly meshed gear.

5. The multi-speed transmission electric drive axle system according to claim 4, characterized in that: The transmission ratios of the first input gear and its meshed gear, the second input gear and its meshed gear, the third input gear and its meshed gear, the first driving gear and its meshed gear, the second driving gear and its meshed gear, and the second constant meshing gear and its meshed gear are different.

6. The multi-speed transmission electric drive axle system according to claim 5, characterized in that: When in the first gear transmission state, the first sliding sleeve is transmission-connected with the first driving gear, the second sliding sleeve is transmission-connected with the third driving gear, and the third sliding sleeve is transmission-connected with the fifth driving gear.

7. The multi-speed transmission electric drive axle system according to claim 5, characterized in that: When in the second gear transmission state, the first sliding sleeve is transmission-connected with the first driving gear, the second sliding sleeve is transmission-connected with the third driving gear, and the third sliding sleeve is transmission-connected with the sixth driving gear.

8. The multi-speed transmission electric drive axle system according to claim 5, characterized in that: When in the third gear transmission state, the first sliding sleeve is transmission-connected with the first driving gear, the second sliding sleeve is transmission-connected with the fourth driving gear, and the third sliding sleeve is transmission-connected with the fifth driving gear.

9. The multi-speed transmission electric drive axle system according to claim 5, characterized in that: When in the fourth gear transmission state, the first sliding sleeve is transmission-connected with the second driving gear, the second sliding sleeve is transmission-connected with the fourth driving gear, and the third sliding sleeve is transmission-connected with the fifth driving gear.

10. The multi-speed transmission electric drive axle system according to claim 5, characterized in that: When in the fifth gear transmission state, the first sliding sleeve is transmission-connected with the second driving gear, the second sliding sleeve is transmission-connected with the fourth driving gear, and the third sliding sleeve is transmission-connected with the sixth driving gear.

Images