Electric drive axle, vehicle and control method of electric drive axle

Abstract

An electric drive axle, a vehicle and a control method of an electric drive axle. The electric drive axle comprises: an electric motor provided with an electric motor output shaft, the electric motor output shaft being provided with a first axial through hole; a transmission assembly comprising a first shell and a transmission mechanism, the first shell being provided with a first internal space, the transmission mechanism being arranged in the first internal space, the electric motor output shaft extending into the first internal space from the outside of the first shell, the transmission mechanism comprising a power input component, a first power output component and a second power output component, the electric motor output shaft, the power input component, the first power output component and the second power output component being coaxially arranged in sequence, and the power input component being provided with a second axial through hole; a first half shaft which passes through the first axial through hole and the second axial through hole and is coaxially connected to the first power output component, a gap being formed between the first half shaft and the hole wall of the first axial through hole; a second half shaft which is coaxially connected to the second power output component; and a first oil seal which is sealedly arranged in the gap, the first oil seal separating the gap from the first internal space. Thus, oil in the first internal space can be prevented from entering the gap, oil churning can be prevented, heating of the first half shaft and the electric motor output shaft can be reduced, and noise can be reduced.

Description

Electric drive axle, vehicle, and electric drive axle control method

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 21, 2023, with application number 202311779740.5 and application name “Electric drive axle, vehicle and control method of electric drive axle”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of vehicle technology, and in particular to an electric drive axle, a control method of the electric drive axle, and a vehicle. Background Art

[0003] Electric drive axles are widely used in the power systems of hybrid vehicles and electric vehicles. Electric drive axles include motors and transmission mechanisms. The kinetic energy output by the motor is transmitted to the vehicle through the transmission mechanism to drive the vehicle.

[0004] Electric drive axles can be classified according to their layout into coaxial electric drive axles, parallel axis electric drive axles, motor and bridge perpendicular electric drive axles, etc. Among them, coaxial electric drive axles have higher transmission efficiency than other drive axles.

[0005] However, existing coaxial electric drive axles still have problems such as severe heat generation and loud noise during operation. Summary of the Invention

[0006] The present application provides an electric drive axle, an electric drive axle control method, and a vehicle, so as to reduce heat generation and noise while maintaining high transmission efficiency of the electric drive axle.

[0007] In a first aspect, the present application provides an electric drive axle, comprising:

[0008] The motor comprises a motor output shaft, wherein the motor output shaft is provided with a first axial through hole;

[0009] A transmission assembly includes a first housing and a transmission mechanism, wherein the first housing has a first interior space, the transmission mechanism is disposed in the first interior space, the motor output shaft extends from the exterior of the first housing into the first interior space, the transmission mechanism includes a power input member, a first power output member, and a second power output member, the motor output shaft, the power input member, the first power output member, and the second power output member being coaxially disposed in sequence, and the power input member being provided with a second axial through hole;

[0010] a first half-shaft, passing through the first axial through-hole and the second axial through-hole, and coaxially connected to the first power output member, with a gap formed between the first half-shaft and the hole wall of the first axial through-hole;

[0011] a second half shaft, coaxially connected to the second power output member;

[0012] A first oil seal is sealingly disposed in the gap, and the first oil seal separates the gap from the first internal space.

[0013] Optionally, the outer diameter of the first semi-shaft is greater than the outer diameter of the second semi-shaft.

[0014] Optionally, the transmission mechanism includes a planetary speed change mechanism and a differential mechanism that are connected to each other in a transmission manner, the power input member is the input member of the planetary speed change mechanism, the second axial through hole axially penetrates the planetary speed change mechanism, and the first power output member and the second power output member are both output members of the differential mechanism.

[0015] Optionally, the planetary speed change mechanism includes a first planetary gear set and a second planetary gear set, the sun gear of the first planetary gear set is the power input component, the planetary carrier of the first planetary gear set is connected to the sun gear of the second planetary gear set, and the planetary carrier of the second planetary gear set is connected to the input component of the differential mechanism.

[0016] Optionally, the motor further includes a second housing, the second housing being connected to the first housing, and the second housing having a second internal space;

[0017] The electric drive axle further includes a first isolating portion, the first isolating portion being disposed on the first housing or the second housing and separating the second interior space from the first interior space, and the first isolating portion being provided with a first through hole through which the output shaft of the power supply motor passes;

[0018] Wherein, a second oil seal and at least one bearing are provided between the inner wall of the first through hole and the outer wall of the motor output shaft.

[0019] Optionally, the transmission mechanism includes a planetary transmission mechanism and a differential mechanism that are transmission-connected to each other, the planetary transmission mechanism includes a first planetary gear set and a second planetary gear set, the sun gear of the first planetary gear set serves as the power input member, the planet carrier of the first planetary gear set is connected to the sun gear of the second planetary gear set, the planet carrier of the second planetary gear set is connected to the input member of the differential mechanism, and the first power output member and the second power output member are both output members of the differential mechanism;

[0020] Among them, a bearing is provided between the planetary carrier of the first planetary gear set and the first isolation part, and a bearing is also provided between the planetary carrier of the second planetary gear set and the first housing; or; a bearing is provided between the planetary carrier of the first planetary gear set and the first housing, and a bearing is also provided between the planetary carrier of the second planetary gear set and the first housing.

[0021] Optionally, the differential mechanism is mounted on a differential mechanism housing, and the differential mechanism housing is integrally formed with the planet carrier of the second planetary gear set.

[0022] In a second aspect, the present application also provides a vehicle comprising any one of the above-described electric drive axles.

[0023] In a third aspect, the present application further provides a control method for an electric drive axle, wherein the electric drive axle is any of the electric drive axles described above, and the control method comprises:

[0024] determining a current slope based on an opening range of a current accelerator pedal opening, a preset mapping relationship between an accelerator pedal opening range and a slope, wherein the slope is a slope of the torque of the motor output shaft and the accelerator pedal opening, wherein in the mapping relationship, a larger opening value of the accelerator pedal opening range corresponds to a smaller slope value;

[0025] The motor torque is obtained according to the current accelerator pedal opening and the current slope.

[0026] Optionally, determining the current slope according to the current accelerator pedal opening range, the mapping relationship between the accelerator pedal opening range and the slope includes:

[0027] Get the current accelerator pedal opening and the preset slope change trigger opening;

[0028] If the current accelerator pedal opening is greater than the preset slope change trigger opening, the current slope is determined to be the first slope; if the current accelerator pedal opening is less than the preset slope change trigger opening, the current slope is determined to be the second slope, and the first slope is less than the second slope.

[0029] The electric drive axle provided in the present application installs a first oil seal between the motor output shaft and the first half-shaft to separate the gap between the motor output shaft and the first half-shaft from the first internal space corresponding to the transmission mechanism installed. This can prevent the oil in the first internal space used to lubricate the transmission mechanism from entering the gap, which is beneficial to preventing oil stirring, and is also beneficial to reducing the heat generation of the first half-shaft and the motor output shaft next to the gap and reducing noise.

[0030] In the electric drive axle control method provided in the present application, since the slope value of the motor torque and the accelerator pedal opening corresponding to the accelerator pedal opening range with a larger opening value is smaller, the torque increases quickly at the initial stage of motor startup, which can improve the motor's response to the power system, and then increases slowly, which can reduce the impact of the vehicle and help ensure the reliability of the vehicle's start. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0032] FIG1 is an exemplary schematic diagram of the electric drive axle of the present application;

[0033] FIG2 is a schematic diagram of an exemplary internal structure of the electric drive axle of the present application;

[0034] FIG3 is a flowchart of a control method for an electric drive axle of the present application;

[0035] FIG4 is a schematic diagram showing the relationship between the accelerator pedal opening and the slope of the torque of the motor output shaft in an example of the control method of the present application.

[0036] Reference Signs: 100 - motor; 110 - motor output shaft; 111 - first axial through-hole; 120 - second housing; 121 - second interior space; 130 - stator; 140 - rotor; 200 - first housing; 201 - first interior space; 300 - transmission mechanism; 310 - first planetary gear set; 311 - power input member; 3111 - second axial through-hole; 312 - first planetary gear; 313 - first ring gear; 314 - first planet carrier; 320 - second planetary gear set; 321 - second sun gear; 322 - second planetary gear; 323 - second ring gear; 324 - second planet carrier; 330 - differential mechanism; 331 - first power output member; 332 - second power output member; 333 - differential mechanism housing; 410 - first axle shaft; 420 - second axle shaft; 510-first oil seal; 520-second oil seal; 530-third oil seal; 610-first isolating portion; 611-first through hole; 620-second isolating portion; 621-second through hole; 710-first motor mounting bearing; 720-second motor mounting bearing; 730-first transmission mechanism support bearing; 740-half-axle support bearing; 750-second transmission mechanism support bearing; 760-third transmission mechanism support bearing; 800-wheel; X-gap.

[0037] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0038] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0039] Electric drive axles can be classified according to their layout into coaxial electric drive axles, parallel axis electric drive axles, motor and bridge perpendicular electric drive axles, etc. Among them, coaxial electric drive axles have higher transmission efficiency than other drive axles.

[0040] In existing coaxial electric drive axles, grease lubrication is usually used for the lubrication between the motor output shaft and the half-bridge inserted into the motor output shaft. The oil in the lubricating transmission mechanism often enters the small gap between the motor output shaft and the corresponding half-bridge, causing oil stirring, resulting in severe heating of the motor output shaft and half-shafts in the electric drive axle, and loud noise from the electric drive axle.

[0041] In view of this, the present application provides an electric drive axle, which sets a gap between the motor output shaft and the half-bridge inserted into the motor output shaft that is sufficient to install an oil seal, and installs an oil seal in the gap to prevent lubricating oil from entering the gap and preventing oil stirring.

[0042] FIG1 shows an exemplary schematic diagram of an electric drive axle of the present application, and FIG2 shows an exemplary structural diagram of an electric drive axle of the present application. Referring to FIG1 and FIG2 , the present application provides an electric drive axle, comprising a motor 100, a transmission assembly, a first half-shaft 410, a second half-shaft 420 and a first oil seal 510. The motor 100 comprises a motor output shaft 110, and the motor output shaft 110 is provided with a first axial through hole 111; the transmission assembly comprises a first housing 200 and a transmission mechanism 300, the first housing 200 having a first internal space 201, the transmission mechanism 300 being provided in the first internal space 201, the motor output shaft 110 extending from the outside of the first housing 200 into the first internal space 201, and the transmission mechanism 300 having The power input member 311, the first power output member 331 and the second power output member 332, the motor output shaft 110, the power input member 311, the first power output member 331 and the second power output member 332 are coaxially arranged in sequence, and the power input member 311 is provided with a second axial through hole 3111; the first half shaft 410 passes through the first axial through hole 111 and the second axial through hole 3111, and is coaxially connected to the first power output member 331, and a gap is formed between the first half shaft 410 and the hole wall of the first axial through hole 111; the second half shaft 420 is coaxially connected to the second power output member 332; the first oil seal 510 is sealed in the gap, and the first oil seal 510 separates the gap and the first internal space 201.

[0043] The motor 100 has the function of converting electrical energy into the rotational kinetic energy of the motor output shaft 110. Exemplarily, the motor 100 further includes a second housing 120, a stator 130, and a rotor 140. The second housing 120 has a second internal space 121. The stator 130 is fixedly mounted in the second internal space 121 of the second housing 120. The motor output shaft 110 is positioned in the second housing 120 via a motor-mounted bearing. The rotor 140 passes through the interior of the stator 130 and is sleeved on the motor output shaft 110, driving the motor output shaft 110 to rotate. It should be noted that the second housing 120 can be detachably connected to the first housing 200, and the second housing 120 is not excluded from being directly integrally formed with the first housing 200. In addition, the first motor-mounted bearing 710 and the second motor-mounted bearing 720 in FIG. 2 are both motor-mounted bearings.

[0044] The transmission mechanism 300 functions to transmit the rotational torque of the motor output shaft 110 to the first half-shaft 410 and the second half-shaft 420. Referring to Figures 1 and 2 , the transmission mechanism 300 includes a planetary transmission mechanism and a differential mechanism 330, which are interconnected. The power input member 311 serves as the input member of the planetary transmission mechanism. The second axial through-hole 3111 axially extends through the planetary transmission mechanism. The first power output member 331 and the second power output member 332 serve as the output members of the differential mechanism 330. Because the rotation center of the planetary transmission mechanism coincides with the rotation center of the power input member 311, and the rotation center of the differential mechanism 330 coincides with the rotation centers of the first power output member 331 and the second power output member 332, this transmission mechanism 300 facilitates maintaining high coaxiality among the motor output shaft 110, the rotation center of the transmission mechanism 300, the first half-shaft 410, and the second half-shaft 420 of the entire electric drive axle, thereby enhancing transmission efficiency.

[0045] During operation, the power of the motor output shaft 110 is first transmitted to the power input component 311 of the transmission mechanism 300, that is, the planetary speed change mechanism, and then transmitted to the differential mechanism 330, and finally transmitted to the first half shaft 410 and the second half shaft 420 through the first power output component 331 and the second power output component 332 in a one-to-one correspondence, thereby driving the wheels 800.

[0046] It should be noted that the planetary transmission mechanism can be a single-stage planetary transmission mechanism, a compound planetary transmission mechanism, or a dual-stage or multi-stage planetary transmission mechanism composed of two or more sets of single-stage planetary assemblies. It should also be noted that the planetary transmission mechanism is typically a planetary reduction mechanism, wherein the power input member 311 of the planetary transmission mechanism is connected to the motor input shaft 110, and the output member is connected to the input member of the differential and outputs a low speed. The compound planetary transmission mechanism can be a Simpson planetary gear transmission mechanism or a Ravigneaux planetary gear mechanism.

[0047] In the electric drive axle of the present application, a gap sufficient for installing a first oil seal 510 is set between the motor output shaft 110 and the first half shaft 410 passing through the motor output shaft 110. By installing the first oil seal 510 between the motor output shaft 110 and the first half shaft 410, the gap between the motor output shaft 110 and the first half shaft 410 is separated from the first internal space 201 corresponding to the transmission mechanism 300. This can prevent the oil in the first internal space 201 used to lubricate the transmission mechanism 300 from entering the gap, which is beneficial to preventing oil stirring from occurring, and is also beneficial to reducing the heat generation of the first half shaft 410 and the motor output shaft 110 next to the gap, thereby reducing noise.

[0048] In some embodiments, the outer diameter of the first axle 410 is greater than the outer diameter of the second axle 420. This results in a greater torsional stiffness of the first axle 410 than the second axle 420, which helps reduce jitter during vehicle startup or shifting. Of course, in this application, the outer diameter of the first axle 410 may be equal to the outer diameter of the second axle 420, nor may the outer diameter of the first axle 410 be smaller than the outer diameter of the second axle 420.

[0049] It should be noted that if the first and second axle shafts 410 and 420 have the same torsional stiffness, that is, the same torsional angle per unit length under the same torque, the first axle shaft 410 will generate a greater torsional angle than the second axle shaft 420 because it is longer than the second axle shaft 420. When the vehicle starts, the wheel on the side of the second axle shaft 420 will be stressed first, resulting in unstable vehicle start and lateral vehicle vibration. Therefore, the design of having the outer diameter of the first axle shaft 410 larger than the outer diameter of the second axle shaft 420 helps reduce the difference in torsional angle output by the two axle shafts, thereby reducing vibration during vehicle start or gear shifting.

[0050] In some embodiments, referring to Figures 1 and 2 , a planetary transmission mechanism includes a first planetary gear set 310 and a second planetary gear set 320. The sun gear of the first planetary gear set 310 serves as a power input member 311. The planet carrier of the first planetary gear set 310 is connected to the sun gear of the second planetary gear set 320. The planet carrier of the second planetary gear set 320 is connected to the input member of the differential mechanism 330. This planetary transmission mechanism is a two-stage planetary transmission mechanism with a large gear ratio, enabling greater ground clearance and improving the vehicle's maneuverability.

[0051] For ease of understanding, in Figures 1 and 2, the first planetary gear set includes a first sun gear, first planetary gears 312, a first ring gear 313, and a first planet carrier 314. The second planetary gear set includes a second sun gear 321, second planetary gears 322, a second ring gear 323, and a second planet carrier 324. Specifically, the first sun gear serves as the power input member 311, the first planet carrier 314 is connected to the second sun gear 321, and the second planet carrier 324 serves as the output of the entire planetary transmission mechanism. Both the first ring gear 313 and the second ring gear 323 are mounted on the first housing. The first planetary gear set 310 implements primary reduction, while the second planetary gear set 320 implements secondary reduction.

[0052] It should be noted that the transmission ratio of a single-stage planetary transmission mechanism and a compound planetary transmission mechanism is relatively small, and the corresponding maximum speed of the motor 100 is relatively low. In addition, the planetary transmission mechanism having the first planetary gear set 310 and the second planetary gear set 320 has a large transmission ratio, and a motor 100 with a relatively high minimum speed can be selected, which is beneficial to reducing the cost of the motor 100. In addition, if the transmission ratio is equal, this bipolar planetary transmission mechanism has a smaller radial dimension than the single-stage planetary transmission mechanism and the compound planetary transmission structure, a larger ground clearance, and better passability. The transmission ratio calculation method of the above-mentioned bipolar planetary transmission mechanism refers to the following formula combination: i=i1*i2 (1)

[0053] Among them, Z t1 Indicates the number of teeth on the first sun gear; Z t2 Indicates the number of teeth on the second sun gear; Z x1 Indicates the number of teeth of the first planetary gear; Z x2 Indicates the number of teeth on the second planetary gear.

[0054] In some embodiments, referring to FIG2 , the motor 100 further includes a second housing 120 , which is connected to the first housing 200 , and the second housing 120 has a second internal space 121 ; the electric drive bridge further includes a first isolating portion 610 , which is disposed on the first housing 200 or the second housing 120 , and the first isolating portion 610 blocks the second internal space 121 and the first internal space 201 , and a first through hole 611 through which the power supply output shaft 110 passes is provided on the first isolating portion 610 ; wherein a second oil seal 520 and at least one bearing are provided between the inner wall of the first through hole 611 and the outer wall of the motor output shaft 110 .

[0055] The first isolating portion 610 may be directly integrally formed with the second housing 120, may be integrally formed with the first housing 200, or may be a separate component, with the first isolating portion 610 being detachably mounted on the first housing 200 or the second housing 120. For example, referring to FIG. 2 , the first isolating portion 610 is a separate isolating component, which is detachably mounted on the second housing 120.

[0056] The "at least one bearing" mentioned above can be a motor-mounted bearing, a transmission mechanism support bearing, or both. In the example of Figure 2 , a first isolating portion 610 is disposed on the second housing 120 , and both a first motor-mounted bearing 710 and a first transmission mechanism support bearing 730 are disposed within the first through-hole 611 of the first isolating portion 610 . This arrangement is more conducive to improving the coaxiality of the rotational centers of the motor output shaft 110 and the transmission mechanism 300 , reducing wear on the second oil seal 520 , and enhancing the reliability and durability of the electric drive axle.

[0057] In this structure, the bearing disposed in the first through hole 611 is beneficial for reducing the change in the radial distance between the inner wall of the through hole and the outer wall of the motor output shaft 110 , thereby reducing the wear of the second oil seal 520 .

[0058] Optionally, the electric drive axle further includes a second isolating portion 620, a third oil seal 530, and a half-shaft support bearing 740. The second isolating portion 620 and the first isolating portion 610 are axially distributed at both ends of the second housing 120. The second isolating portion 620 is provided with a second through-hole 621, through which the first half-shaft 410 passes. The third oil seal 530 is disposed between the inner wall of the second through-hole 621 and the outer wall of the motor output shaft 110. The half-shaft support bearing 740 is disposed between the inner wall of the second through-hole 621 and the outer wall of the first half-shaft 410. In this structure, the half-shaft support bearing 740 disposed in the second through-hole 621 not only improves the coaxiality between the motor output shaft 110 and the first half-shaft 410, but also helps reduce wear on the third oil seal 530, thereby improving the reliability and durability of the electric drive axle.

[0059] In some embodiments, referring to Figures 1 and 2, the transmission mechanism 300 includes a planetary speed change mechanism and a differential mechanism 330 that are mutually transmission-connected, the planetary speed change mechanism includes a first planetary gear set 310 and a second planetary gear set 320, the sun gear of the first planetary gear set 310 is a power input component 311, the planet carrier of the first planetary gear set 310 is connected to the sun gear of the second planetary gear set 320, the planet carrier of the second planetary gear set 320 is connected to the input component of the differential mechanism 330, and the first power output component 331 and the second power output component 332 are both output components of the differential mechanism 330; wherein, a bearing is provided between the planet carrier of the first planetary gear set 310 and the first isolation portion 610, and a bearing is also provided between the planet carrier of the second planetary gear set 320 and the first housing 200.

[0060] A bearing is provided between the planet carrier of the first planetary gear set 310 and the first isolating portion 610 , that is, a bearing is provided between the first planet carrier 314 and the first isolating portion 610 .

[0061] A bearing is also provided between the planet carrier of the second planetary gear set 320 and the first housing 200 , that is, a bearing is provided between the second planet carrier 324 and the first housing 200 .

[0062] The bearings disposed between the planet carrier of the first planetary gear set 310 and the first isolating portion 610, and the bearings disposed between the planet carrier of the second planetary gear set 320 and the first housing 200, can both be referred to as planetary speed change mechanism support bearings or transmission mechanism support bearings. In FIG2 , the bearing disposed between the planet carrier of the first planetary gear set 310 and the first isolating portion 610 is a first transmission mechanism support bearing 730, and the bearing disposed between the planet carrier of the second planetary gear set 320 and the first housing 200 is a second transmission mechanism support bearing 750.

[0063] This structure is equivalent to supporting the planetary carriers of the two-stage planetary gear sets in the planetary transmission mechanism, which is more conducive to improving the coaxiality between the rotation center of the planetary transmission mechanism and the motor output shaft 110, and is also conducive to improving the coaxiality between the first half shaft 410, the second half shaft 420 and the motor output shaft 110, thereby improving the durability and reliability of the electric drive axle.

[0064] In other embodiments (not shown), bearings are provided between the planet carrier of the first planetary gear set 310 and the first housing 200, and bearings are also provided between the planet carrier of the second planetary gear set 320 and the first housing 200. In other words, the bearings of the first transmission mechanism 300 are provided between the planet carrier of the first planetary gear set 310 and the first housing 200.

[0065] Optionally, referring to Figures 1 and 2, the differential mechanism 330 is installed on the differential mechanism 330 housing, and the differential mechanism 330 housing and the planetary carrier of the second planetary gear set 320 are integrally formed, that is, the differential mechanism 330 housing and the second planetary carrier 324 are integrally formed, and a third transmission mechanism support bearing 760 is provided between the differential mechanism 330 housing and the first housing 200. This method is conducive to improving the coaxiality of the rotation center of the second planetary gear set 320 and the rotation center of the differential mechanism 330, and is also conducive to improving the durability and reliability of the electric drive axle.

[0066] It should be noted that any of the above electric drive axles can be applied to vehicles, which can be pure electric vehicles or hybrid vehicles. Accordingly, the present application provides a vehicle comprising the electric drive axle of any of the above embodiments.

[0067] The present application also provides a control method for an electric drive axle, the electric drive axle being any of the above embodiments, with reference to FIG3 and FIG4 , the control method comprising:

[0068] Step S100, determine the current slope based on the acceleration pedal opening range of the current accelerator pedal opening, the preset acceleration pedal opening range and the mapping relationship between the slope, which is the slope P of the torque T of the motor output shaft 110 and the accelerator pedal opening K. In the mapping relationship, the larger the opening value of the accelerator pedal opening range, the smaller the corresponding slope value.

[0069] The opening of the accelerator pedal is obtained by a sensor set on or near the accelerator pedal. The opening of the accelerator pedal reflects the driving intention. For example, an increase in the opening of the accelerator pedal indicates the driving intention to accelerate the vehicle, and a decrease in the opening of the accelerator pedal indicates the driving intention to decelerate the vehicle.

[0070] There are at least two preset accelerator pedal opening ranges. In the example of FIG3 , two accelerator pedal opening ranges are set, corresponding to the two ranges of A≤K≤B and B≤K≤C, respectively, and there are two corresponding slope values.

[0071] For example, in step S100, referring to FIG4 , determining the current slope according to the current accelerator pedal opening range, the mapping relationship between the accelerator pedal opening range and the slope includes:

[0072] Step S110: Obtain the current accelerator pedal opening and the preset slope change trigger opening; for example, in FIG4 , the accelerator pedal opening B is the preset slope change trigger opening.

[0073] Step S120: If the current accelerator pedal opening is greater than the preset slope change trigger opening, the current slope is determined to be the first slope; if the current accelerator pedal opening is less than the preset slope change trigger opening, the current slope is determined to be the second slope. Referring to FIG. 4 , the first slope corresponding to the horizontal coordinate B≤K≤C is less than the second slope corresponding to the horizontal coordinate A≤K≤B.

[0074] Step S200: Obtain the motor torque based on the current accelerator pedal opening and the current slope. For example, in FIG4 , the value of the vertical coordinate T can be obtained based on the current value of the accelerator pedal opening K and the corresponding slope.

[0075] In the control method of the present application, since the slope value corresponding to the accelerator pedal opening range is smaller when the opening value is larger, during the vehicle startup process, the motor torque first increases rapidly, making the motor 100 more responsive to the power system; and then accelerates at a relatively slow speed, which is more conducive to controlling the torsional angle difference between the first half-shaft 410 and the second half-shaft 420, reducing the impact of the vehicle, avoiding wheel slippage, and ensuring reliable vehicle start-up.

[0076] In the description of the embodiments of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted" and "connected" should be understood in a broad sense. For example, they may refer to a fixed connection, an indirect connection via an intermediate medium, internal communication between two components, or an interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on specific circumstances.

[0077] The terms "first", "second", etc. in the description and claims of the embodiments of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electric drive axle, characterized in that: include: The motor comprises a motor output shaft, wherein the motor output shaft is provided with a first axial through hole; A transmission assembly, comprising a first housing and a transmission mechanism, wherein the first housing has a first internal space, the transmission mechanism is arranged in the first internal space, the motor output shaft extends from the outside of the first housing into the first internal space, the transmission mechanism has a power input member, a first power output member and a second power output member, the motor output shaft, the power input member, the first power output member and the second power output member are coaxially arranged in sequence, and the power input member is provided with a second axial through hole; A first half shaft, passing through the first axial through hole and the second axial through hole, and coaxially connected to the first power output member, with a gap formed between the first half shaft and the hole wall of the first axial through hole; a second half shaft, coaxially connected to the second power output member; The first oil seal is sealed in the gap, and the first oil seal separates the gap from the first internal space.

2. The electric drive axle according to claim 1, characterized in that: The outer diameter of the first semi-shaft is greater than the outer diameter of the second semi-shaft.

3. The electric drive axle according to claim 1, characterized in that: The transmission mechanism includes a planetary transmission mechanism and a differential mechanism that are connected to each other in transmission. The second axial through hole axially penetrates the planetary transmission mechanism. The power input component is the input component of the planetary transmission mechanism. The first power output component and the second power output component are both output components of the differential mechanism.

4. The electric drive axle according to claim 3, characterized in that: The planetary speed change mechanism includes a first planetary gear set and a second planetary gear set, the sun gear of the first planetary gear set is the power input member, the planet carrier of the first planetary gear set is connected to the sun gear of the second planetary gear set, and the planet carrier of the second planetary gear set is connected to the input member of the differential mechanism.

5. The electric drive axle according to claim 1, characterized in that: The motor further comprises a second housing, the second housing is connected to the first housing, and the second housing has a second internal space; The electric drive axle further includes a first isolating portion, which is disposed on the first housing or the second housing and blocks the second internal space from the first internal space, and a first through hole is disposed on the first isolating portion for the output shaft of the power supply machine to pass through; Wherein, a second oil seal and at least one bearing are arranged between the inner wall of the first through hole and the outer wall of the motor output shaft.

6. The electric drive axle according to claim 5, characterized in that: The transmission mechanism comprises a planetary transmission mechanism and a differential mechanism which are transmission-connected to each other, the planetary transmission mechanism comprises a first planetary gear set and a second planetary gear set, the sun gear of the first planetary gear set is the power input member, the planet carrier of the first planetary gear set is connected to the sun gear of the second planetary gear set, the planet carrier of the second planetary gear set is connected to the input member of the differential mechanism, and the first power output member and the second power output member are both output members of the differential mechanism; Among them, a bearing is arranged between the planetary carrier of the first planetary gear set and the first isolation part, and a bearing is also arranged between the planetary carrier of the second planetary gear set and the first housing; or; a bearing is arranged between the planetary carrier of the first planetary gear set and the first housing, and a bearing is also arranged between the planetary carrier of the second planetary gear set and the first housing.

7. The electric drive axle according to claim 6, characterized in that: The differential mechanism is mounted on a differential mechanism housing, and the differential mechanism housing is integrally formed with a planet carrier of the second planetary gear set.

8. A vehicle, characterized in that: Comprising the electric drive axle as claimed in any one of claims 1-7.

9. A control method for an electric drive axle, characterized in that: The electric drive axle is the electric drive axle according to any one of claims 1 to 7, and the control method comprises: Determine the current slope according to the current accelerator pedal opening range, the preset accelerator pedal opening range and the mapping relationship of the slope, wherein the slope is the slope of the torque of the motor output shaft and the accelerator pedal opening, and in the mapping relationship, the accelerator pedal opening range with a larger opening value has a smaller corresponding slope value; The motor torque is obtained according to the current acceleration pedal opening and the current slope.

10. The control method of the electric drive axle according to claim 9, characterized in that: Determining the current slope according to the current accelerator pedal opening range, the mapping relationship between the accelerator pedal opening range and the slope includes: Get the current accelerator pedal opening and the preset slope change trigger opening; If the current accelerator pedal opening is greater than the preset slope change trigger opening, the current slope is determined to be the first slope. If the current accelerator pedal opening is less than the preset slope change trigger opening, the current slope is determined to be the second slope. The first slope is less than the second slope.

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