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

Abstract

The application provides an electric drive axle, a vehicle and a control method of the electric drive axle. The electric drive axle comprises a shell assembly, a motor assembly, a transmission mechanism, a first half shaft, a second half shaft and a first support. The shell assembly has a hollow space. At least two first bearings are arranged between a motor output shaft of the motor assembly and the shell assembly. At least two second bearings are arranged between the transmission mechanism and the shell assembly. The first support is arranged in the shell assembly and separates the hollow space to form a motor assembly mounting space and a transmission mechanism mounting space. At least one first bearing and at least one second bearing are mounted on the first support. In the application, since at least one first bearing and at least one second bearing are mounted on the first support, the coaxiality of the motor output shaft and the transmission mechanism can be improved, which is beneficial to reducing the wear between parts in the electric drive axle and improving the reliability and durability of the electric drive axle.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to an electric drive axle, a vehicle, and a control method for the electric drive axle. Background Technology

[0002] Electric drive axles are widely used in the power systems of hybrid and electric vehicles. An electric drive axle includes a motor and a transmission mechanism. The kinetic energy output by the motor is transmitted to the vehicle through the transmission mechanism to drive the vehicle.

[0003] According to their arrangement, electric drive axles can be classified into coaxial electric drive axles, parallel-axis electric drive axles, and electric drive axles where the motor and axle are perpendicular. Among them, coaxial electric drive axles have higher transmission efficiency than other drive axles.

[0004] However, existing coaxial electric drive bridges are not reliable or durable enough and are prone to failure. Summary of the Invention

[0005] This application provides an electric drive axle, a vehicle, and a control method for the electric drive axle, so as to improve the reliability and durability of the electric drive axle while ensuring that the electric drive axle has high transmission efficiency.

[0006] In a first aspect, this application provides an electric drive bridge, comprising:

[0007] The outer casing assembly has a hollow space;

[0008] A motor assembly has a motor output shaft, the motor output shaft having a first axial through hole, and at least two first bearings are disposed between the motor output shaft and the housing assembly;

[0009] The transmission mechanism has a power input component, a first power output component, and a second power output component. The motor output shaft, the power input component, the first power output component, and the second power output component are arranged coaxially in sequence. The power input component is provided with a second axial through hole. At least two second bearings are provided between the transmission mechanism and the housing assembly.

[0010] The first half-shaft passes through the first axial through hole and the second axial through hole, and is coaxially connected to the first power output component.

[0011] The second half-shaft is coaxially connected to the second power output component;

[0012] The first support member has a first central hole. The first support member is disposed inside the housing assembly and divides the hollow space to form a motor assembly installation space and a transmission mechanism installation space.

[0013] The motor output shaft passes through the first central hole and is coaxially arranged with the first central hole. At least one first bearing and at least one second bearing are both mounted on the first support member.

[0014] Optionally, the electric drive axle further includes a first oil seal, which seals between the wall of the first central hole and the motor output shaft, and the first oil seal is adjacent in the axial direction to the first bearing mounted on the first support.

[0015] Optionally, the electric drive bridge further includes:

[0016] The second support member has a second central hole and is mounted on the housing assembly. The first half-shaft coaxially passes through the second central hole.

[0017] The third bearing is disposed between the wall of the second central hole and the first half-shaft;

[0018] The second oil seal is located between the wall of the second central hole and the motor output shaft, and the second oil seal is adjacent to the third bearing in the axial direction.

[0019] Optionally, a gap is formed between the wall of the first axial through hole and the first half-shaft, and the electric drive bridge further includes:

[0020] The third oil seal is sealed between the hole wall of the second central hole and the first half shaft. The third oil seal is disposed on the side of the third bearing opposite to the motor output shaft and is axially adjacent to the third bearing. The second oil seal is disposed on the side of the third bearing facing the motor output shaft.

[0021] A fourth oil seal is provided between the housing assembly and the second half-shaft, and the fourth oil seal is axially adjacent to the second bearing disposed between the housing assembly and the second half-shaft, the gap being in communication with the installation space of the transmission mechanism.

[0022] Optionally, a gap is formed between the wall of the first axial through hole and the first half-shaft, and the electric drive bridge further includes:

[0023] The third oil seal is sealed between the second central hole wall and the first half shaft. The third oil seal is disposed on the side of the third bearing opposite to the motor output shaft and is axially adjacent to the third bearing. The second oil seal is disposed on the side of the third bearing facing the motor output shaft.

[0024] A fourth oil seal is provided between the housing assembly and the second half-shaft, and the fourth oil seal is axially adjacent to the second bearing disposed between the housing assembly and the second half-shaft.

[0025] The fifth oil seal is disposed within the gap and separates the gap from the installation space of the transmission mechanism.

[0026] Optionally, the electric drive axle further includes a second oil seal that seals between the housing assembly and the motor output shaft, and the second oil seal is adjacent to another of the first bearings in the axial direction.

[0027] Optionally, the housing assembly includes a motor housing and a transmission mechanism housing connected together, and the first support member is disposed on the motor housing; or, the housing assembly includes a motor housing and a transmission mechanism housing connected together, and the first support member is disposed on the transmission mechanism housing.

[0028] Optionally, the transmission mechanism includes a planetary transmission mechanism and a differential mechanism that are connected to each other in a transmission manner. The power input component is the input component of the planetary transmission mechanism, and the first power output component and the second power output component are both output components of the differential mechanism.

[0029] Secondly, this application provides a vehicle including any of the electric drive axles described above.

[0030] Thirdly, this application provides a control method for an electric drive bridge, wherein the electric drive bridge is any of the electric drive bridges described above, and the method includes:

[0031] Based on the current accelerator pedal opening range and the preset mapping relationship between the accelerator pedal opening range and the slope, the current slope is determined. The slope is the ratio of the torque of the motor output shaft to the slope of the accelerator pedal opening. In the mapping relationship, the larger the opening value corresponding to the accelerator pedal opening range, the smaller the corresponding slope value.

[0032] The motor torque is obtained based on the current acceleration pedal opening and the current slope.

[0033] Optionally, determining the current slope based on the current accelerator pedal opening range and the mapping relationship between the accelerator pedal opening range and the slope includes:

[0034] Get the current accelerator pedal opening and the preset slope change trigger opening;

[0035] 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.

[0036] The electric drive axle and vehicle provided in this application have a first support member provided inside the housing assembly. The first center hole of the first support member is coaxial with the motor output shaft. By installing at least one first bearing and at least one second bearing in the first center hole, the coaxiality between the motor output shaft and the transmission mechanism can be improved, which is beneficial to reducing the wear between the components inside the electric drive axle, and thus improving the reliability and durability of the electric drive axle.

[0037] In the electric drive axle control method provided in this application, since the motor torque corresponding to the accelerator pedal opening range with a larger opening value is smaller with a smaller slope value of the accelerator pedal opening, the torque increases rapidly in the initial stage of motor start-up, which can improve the motor's response to the power system. Then, the torque increases slowly, which can reduce the impact of the vehicle and help ensure the reliability of vehicle start-up. Attached Figure Description

[0038] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0039] Figure 1 This is an exemplary structural diagram of the electric drive axle of this application;

[0040] Figure 2 for Figure 1 Enlarged view of section I in the middle;

[0041] Figure 3 for Figure 1 Enlarged view at point II;

[0042] Figure 4 An exemplary structural diagram showing a differential housing integrated with a planetary carrier;

[0043] Figure 5 This is a flowchart of the control method for the electric drive axle of this application;

[0044] Figure 6 This is a schematic diagram illustrating the slope relationship between the accelerator pedal opening and the torque of the motor output shaft in one example of the control method of this application.

[0045] Figure label:

[0046] 100 - Housing assembly; A - First end; B - Second end; 110 - Motor housing; 120 - Transmission mechanism housing; 111 - Motor assembly mounting space; 121 - Transmission mechanism mounting space;

[0047] 200 - Motor assembly; 210 - Motor output shaft; 211 - First axial through hole; 220 - Stator; 230 - Rotor;

[0048] 300 - Transmission mechanism; 311 - Power input component; 3111 - Second axial through hole; 3121 - First planetary gear; 3122 - Second planetary gear; 313 - Ring gear; 314 - Planetary carrier; 321 - First power output component; 322 - Second power output component; 323 - Differential housing;

[0049] 410 - First half-shaft; 420 - Second half-shaft;

[0050] 510 - First bearing; 520 - Second bearing; 530 - Third bearing;

[0051] 610 - First oil seal; 620 - Second oil seal; 630 - Third oil seal; 640 - Fourth oil seal; 650 - Fifth oil seal;

[0052] 700 - First support member; 710 - First center hole; 713 - First sub-hole;

[0053] 800 - Second support member; 801 - Second center hole;

[0054] X-gap.

[0055] The accompanying drawings have illustrated specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to specific embodiments. Detailed Implementation

[0056] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0057] An electric drive axle includes a motor and a transmission mechanism. The kinetic energy output by the motor is transmitted to the vehicle through the transmission mechanism to drive the vehicle. Electric drive axles can be classified according to their arrangement into coaxial electric drive axles, parallel-axis electric drive axles, and electric drive axles where the motor and axle are perpendicular. Among these, coaxial electric drive axles have higher transmission efficiency compared to other types of drive axles.

[0058] In a coaxial electric drive axle, the motor output shaft, the rotation center of the transmission mechanism, and the two half-shafts of the electric drive axle are all arranged coaxially. However, in existing coaxial electric drive axles, the coaxiality between the motor output shaft, the rotation center of the transmission mechanism, and the two half-shafts of the electric drive axle is not high enough, resulting in greater wear on the parts inside the coaxial electric drive axle. Consequently, the reliability and durability of the coaxial electric drive axle are not high enough, and it is prone to failure.

[0059] In view of this, this application provides an electric drive axle that improves the reliability of the coaxial electric drive axle by increasing the coaxiality between the rotation center of the transmission mechanism and the motor output shaft.

[0060] See also Figures 1 to 3 The electric drive axle of this application includes a housing assembly 100, a motor assembly 200, a transmission mechanism 300, a first half-shaft 410, a second half-shaft 420, and a first support member 700. The housing assembly 100 has a hollow space. The motor assembly 200 has a motor output shaft 210, which has a first axial through hole 211. At least two first bearings 510 are provided between the motor output shaft 210 and the housing assembly 100. The transmission mechanism 300 has a power input member 311, a first power output member 321, and a second power output member 322. The motor output shaft 210, the power input member 311, the first power output member 321, and the second power output member 322 are arranged coaxially in sequence. The power input member 311 has a second axial through hole 311. 11. At least two second bearings 520 are provided between the transmission mechanism 300 and the housing assembly 100; the first half-shaft 410 passes through the first axial through hole 211 and the second axial through hole 3111, and is coaxially connected to the first power output component 321; the second half-shaft 420 is coaxially connected to the second power output component 322; the first support member 700 has a first central hole 710, the first support member 700 is disposed inside the housing assembly 100, and the hollow space is separated to form a motor assembly mounting space 111 and a transmission mechanism mounting space 121; wherein, the motor output shaft 210 passes through the first central hole 710, and the motor output shaft 210 is coaxially arranged with the first central hole 710, and at least one first bearing 510 and at least one second bearing 520 are both mounted on the first support member 700.

[0061] In addition to the motor output shaft 210, the aforementioned motor assembly 200 typically includes a stator 220 and a rotor 230. The stator 220 is mounted on the housing assembly 100, and the rotor 230 is fitted around the motor output shaft 210. When the rotor 230 of the motor assembly 200 rotates relative to the stator 220, it drives the motor output shaft 210 to rotate, thus outputting power.

[0062] The function of the aforementioned transmission mechanism 300 is to transmit the power output from the motor output shaft 210 to the first half-shaft 410 and the second half-shaft 420. For example, see [link to example]. Figure 1 The transmission mechanism 300 includes a planetary transmission mechanism and a differential mechanism that are connected to each other. The power input component 311 is the input component of the planetary transmission mechanism, and the first power output component 321 and the second power output component 322 are both output components of the differential mechanism.

[0063] For example, see Figure 1 The planetary transmission mechanism is a composite planetary transmission mechanism, comprising a sun gear, a double planetary gear set, a ring gear 313, and a planet carrier 314. The sun gear is the aforementioned power input component 311. The double planetary gear set includes a first planetary gear 3121 and a second planetary gear 3122 coaxially arranged. The first planetary gear 3121 meshes with the sun gear, and the second planetary gear 3122 meshes with the ring gear 313. The double planetary gear set is mounted on the planet carrier 314, which serves as the output component of the entire planetary transmission mechanism. The transmission ratio calculation formula for this planetary transmission mechanism is:

[0064] +1 (1)

[0065] In formula (1): Indicates the number of teeth on the sun gear; Indicates the number of teeth on the first planetary gear; Indicates the number of teeth on the second planetary gear; This indicates the number of teeth on the gear ring.

[0066] It should be noted that the planetary gears in the planetary transmission mechanism may not be double-linked, but may consist of only a single planetary gear; the planetary transmission mechanism may also adopt a two-stage transmission method. This two-stage transmission planetary transmission mechanism includes two sets of planetary gear sets with their rotation centers coaxial and interconnected. It should be noted that both double-linked planetary gears and the above-mentioned two-stage transmission planetary transmission mechanism can achieve a larger transmission ratio, which is more conducive to reducing motor costs.

[0067] The function of the first bearing 510 is to position the motor assembly 200 within the housing assembly 100, and the function of the second bearing 520 is to position the transmission mechanism 300 within the housing assembly 100. Figure 1In the example shown, one second bearing 520 is disposed between the planetary carrier 314 of the transmission mechanism 300 and the housing assembly 100, and the other second bearing 520 is disposed between the housing of the differential mechanism and the housing assembly 100. The aforementioned first support member 700 can be disposed within the housing assembly 100 in at least two ways: in one possible implementation, see [link to relevant documentation]. Figure 1 The aforementioned housing assembly 100 includes a motor housing 110 and a transmission mechanism housing 120 connected together, and a first support member 700 is disposed on the motor housing 110; in another possible implementation (not shown), the housing assembly 100 includes a motor housing 110 and a transmission mechanism housing 120 connected together, and a first support member 700 is disposed on the transmission mechanism housing 120.

[0068] In the electric drive axle of this application, the motor output shaft 210 is positioned within the housing assembly 100 via a first bearing 510, and the transmission mechanism 300 is positioned within the housing assembly 100 via a second bearing 520. Both are based on the housing assembly 100 as the installation reference. On this basis, a first support member 700 is provided within the housing assembly 100. The first center hole 710 of the first support member 700 is coaxial with the motor output shaft 210, and at least one first bearing 510 and at least one second bearing 520 are installed within the first center hole 710. This can improve the coaxiality between the motor output shaft 210 and the transmission mechanism 300, which is beneficial to reducing wear between components within the electric drive axle, and thus improving the reliability and durability of the electric drive axle.

[0069] It is worth mentioning that, Figure 1 In this design, the output component of the planetary gear transmission mechanism is the planet carrier 314. The second bearing 520, mounted on the first support 700, is fitted onto one end of the planet carrier 314. This means the second bearing 520 is supported on the output component of the planetary gear transmission mechanism, rather than the input component. This improves the coaxiality of the first half-shaft 410 and the second half-shaft 420 with the motor output shaft 210, thus enhancing the reliability of the electric drive axle. However, it should be emphasized that this application does not exclude the possibility of directly supporting the second bearing 520 on the sun gear axle.

[0070] Optional, see also Figure 1 , Figure 4 The differential housing 323 and planetary carrier 314 are integrally formed, which is more conducive to improving the coaxiality between the rotation center of the transmission mechanism and the motor output shaft 210. In some embodiments, see Figure 1 , Figure 3 The electric drive axle also includes a first oil seal 610, which seals between the hole wall of the first central hole 710 and the motor output shaft 210, and the first oil seal 610 is adjacent to the first bearing 510 mounted on the first support 700 in the axial direction.

[0071] In this structure, since the first oil seal 610 is adjacent to the first bearing 510 mounted on the first support 700, the first bearing 510 makes the coaxiality of the first oil seal 610 and the motor output shaft 210 higher, which helps to reduce wear and also helps to prevent lubricating oil from entering the motor, making the motor less prone to failure. This improves the reliability and durability of the electric drive axle, and makes the first oil seal 610 less prone to damage.

[0072] Optional, see Figure 1 The first central hole 710 is a stepped hole, comprising a first sub-hole 713, a second sub-hole, and a third sub-hole connected sequentially along the axial direction. The diameter of the third sub-hole is larger than that of the second sub-hole, and the diameter of the second sub-hole is larger than that of the first sub-hole 713. A corresponding second bearing 520 is installed in the third sub-hole, and a corresponding first bearing 510 is installed in the second sub-hole. The first oil seal 610 is installed in the first sub-hole 713. In this configuration, the first oil seal 610 is installed on the section with the smallest diameter within the first central hole 710. The overall size of the first oil seal 610 is relatively small, resulting in less runout, which is more conducive to reducing oil seal wear and improving the durability and reliability of the electric drive axle.

[0073] See Figure 1 and Figure 2 The electric drive axle also includes a second oil seal. It should be noted that the aforementioned first and second oil seals can also be referred to as motor oil seals. The purpose of both the first and second oil seals is to reliably seal the motor rotor 230 and stator 220 within the motor housing, preventing external oil or contaminants from affecting the normal operation of the motor and preventing motor failure. To improve the reliability of the second oil seal 620, the following methods can be adopted:

[0074] In an alternative embodiment (not shown), the electric drive axle further includes a second oil seal that seals between the housing assembly and the motor output shaft, and the second oil seal is axially adjacent to another first bearing. In this configuration, the second oil seal, supported by the corresponding first bearing, also maintains a high degree of coaxiality with the motor output shaft, resulting in less wear.

[0075] In another alternative approach, see Figure 1 and Figure 2The electric drive axle includes a second support member 800, a third bearing 530, and a second oil seal 620. The second support member 800 has a second central hole 801 and is mounted on the housing assembly 100. A first half-shaft 410 coaxially passes through the second central hole 801. The third bearing 530 is located between the hole wall of the second central hole 801 and the first half-shaft 410. The second oil seal 620 seals between the hole wall of the second central hole 801 and the motor output shaft 210, and the second oil seal 620 and the third bearing 530 are adjacent to each other in the axial direction.

[0076] The aforementioned third bearing 530 can also be called a half-shaft bearing. The first half-shaft 410 has a large axial length. Setting this third bearing 530 can make the coaxiality between the first half-shaft 410 and the motor output shaft 210 higher.

[0077] In this type of electric drive axle, the second oil seal 620 and the third bearing 530 are axially adjacent, which also helps to reduce the wear of the second oil seal 620 and improve the reliability of the electric drive axle.

[0078] Optional, see Figure 1 , Figure 2 The motor output shaft 210 has a first end A and a second end B along the axial direction. A mounting shaft section is formed at the first end A, which is adjacent to the third bearing 530. This mounting shaft section is the smallest diameter section on the motor output shaft 210. The second oil seal 620 is positioned between the mounting shaft section and the second support member 800. This arrangement, with the second oil seal 620 installed at its smallest diameter position, minimizes runout, thus improving reliability and durability.

[0079] In the electric drive axle, besides the motor assembly 200 requiring sealing, the transmission mechanism 300 also needs to be sealed within the transmission mechanism housing 120, ensuring that the transmission mechanism 300 is forcibly lubricated by oil within a closed lubrication space. The sealing of the transmission mechanism 300 can be achieved using the following methods:

[0080] In some embodiments, see reference Figures 1 to 3 A gap X is formed between the wall of the first axial through hole 211 and the first half-shaft 410. The electric drive axle also includes a third oil seal 630 and a fourth oil seal 640. The third oil seal 630 seals between the wall of the second central hole 801 and the first half-shaft 410. The third oil seal 630 is located on the side of the third bearing 530 facing away from the motor output shaft 210 and is axially adjacent to the third bearing 530. The second oil seal 620 is located on the side of the third bearing 530 facing the motor output shaft 210. The fourth oil seal 640 seals between the housing assembly 100 and the second half-shaft 420, and the fourth oil seal 640 is axially adjacent to the second bearing 520 located between the housing assembly 100 and the second half-shaft 420. The gap X is interconnected with the transmission mechanism mounting space 121, that is, there is no gap X. Figure 3 The fifth oil seal in the system.

[0081] In this structure, the gap X is connected to the transmission mechanism mounting space 121. That is, the lubrication space includes both the gap X and the transmission mechanism mounting space 121. The forced lubricating oil exists in both the transmission mechanism mounting space 121 and the gap X.

[0082] In this configuration, the third oil seal 630 is installed inside the second central hole 801. Since the third bearing 530 is also supported inside the second central hole 801, the third oil seal 630 can maintain a high degree of coaxiality with the first half-shaft 410, which is beneficial to improving the reliability and durability of the third oil seal 630. Under the support of the corresponding second bearing 520, the fourth oil seal 640 can also maintain a high degree of coaxiality with the second bearing 520, which is beneficial to improving the reliability and durability of the fourth oil seal 640.

[0083] In other embodiments, see reference 1 Figures 1 to 3 A gap X is formed between the wall of the first axial through hole 211 and the first half-shaft 410. The electric drive axle also includes a third oil seal 630, a fourth oil seal 640 and a fifth oil seal 650. The third oil seal 630 seals between the wall of the second central hole 801 and the first half-shaft 410. The third oil seal 630 is disposed on the side of the third bearing 530 facing away from the motor output shaft 210 and is axially adjacent to the third bearing 530. The second oil seal 620 is disposed on the side of the third bearing 530 facing the motor output shaft 210. The fourth oil seal 640 seals between the housing assembly 100 and the second half-shaft 420, and the fourth oil seal 640 is axially adjacent to the second bearing 520 disposed between the housing assembly 100 and the second half-shaft 420. The fifth oil seal 650 is disposed in the gap X and separates the gap X from the transmission mechanism mounting space 121.

[0084] In this way, the third oil seal 630 and the fourth oil seal 640 also have high reliability and durability. On this basis, the fifth oil seal 650 separates the gap X from the transmission mechanism installation space 121. The forced lubrication oil exists only in the transmission mechanism installation space 121 and will not enter the gap X. This can avoid the oil churning phenomenon in the gap X, which is conducive to reducing noise and improving transmission efficiency.

[0085] In some embodiments, if the outer diameter of the first half-shaft 410 is greater than the outer diameter of the second half-shaft 420, then the torsional stiffness of the first half-shaft 410 is greater than that of the second half-shaft 420, which is beneficial to reducing the vibration generated during vehicle start-up or gear shifting.

[0086] It should be noted that if the first half-shaft 410 and the second half-shaft 420 have the same torsional stiffness, meaning the same torsional angle per unit length under the same torque, then since the first half-shaft 410 is longer than the second half-shaft 420, the first half-shaft 410 will generate a larger torsional angle than the second half-shaft 420. When the vehicle starts, the wheel on the side of the second half-shaft 420 will bear the force first, resulting in instability and lateral vibration. Therefore, this arrangement, where the outer diameter of the first half-shaft 410 is larger than that of the second half-shaft 420, helps to reduce the difference in torsional angle output by the two half-shafts, thereby reducing vibration during vehicle start-up or gear shifting.

[0087] It should be noted that any of the above-described electric drive axles can be applied to vehicles, which can be pure electric vehicles or hybrid vehicles. Accordingly, this application provides a vehicle including the electric drive axle of any of the above embodiments.

[0088] This application also provides a control method for an electric drive bridge, wherein the electric drive bridge is any of the electric drive bridges described in the above embodiments. See also... Figure 5 The control method includes:

[0089] Step S100: Determine the current slope based on the current accelerator pedal opening range and the preset mapping relationship between the accelerator pedal opening range and the slope. The slope is the slope P between the torque T of the motor output shaft 210 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.

[0090] The opening degree of the accelerator pedal is obtained by a sensor located on or near the accelerator pedal. The opening degree of the accelerator pedal reflects the driving intention. For example, an increase in the accelerator pedal opening indicates a driving intention to accelerate the vehicle, while a decrease in the accelerator pedal opening indicates a driving intention to decelerate the vehicle.

[0091] The aforementioned preset acceleration pedal opening range has at least two values. Figure 6 In the example, two accelerator pedal opening ranges are set, corresponding to the ranges A≤K≤B and B≤K≤C respectively, and there are two corresponding slope values.

[0092] For example, in step S100, see Figure 6 Based on the current accelerator pedal opening range and the mapping relationship between the accelerator pedal opening range B and the slope, the current slope is determined as follows:

[0093] Step S110: Obtain the current accelerator pedal opening and the preset slope change trigger opening;

[0094] Step S120: If the current accelerator pedal opening is greater than the preset slope change trigger opening, determine the current slope as the first slope; if the current accelerator pedal opening is less than the preset slope change trigger opening, determine the current slope as the second slope. See [link to relevant documentation]. Figure 6 The first slope corresponding to the x-coordinate B≤K≤C is less than the second slope corresponding to the x-coordinate A≤K≤B.

[0095] S200: Based on the current acceleration pedal opening and the current slope, the motor torque is obtained. For example, Figure 6 In the above, based on the current acceleration pedal opening K and the corresponding slope, the value of the vertical coordinate T can be obtained.

[0096] In the control method of this application, since the slope value corresponding to the larger opening value of the accelerator pedal is smaller, the motor torque increases rapidly during vehicle startup, making the motor more responsive to the power system; then it accelerates at a relatively slower speed, which is more conducive to controlling the difference in torsional angle between the first half-shaft and the second half-shaft, reducing the impact of the vehicle, avoiding wheel slippage, and ensuring reliable vehicle start-up.

[0097] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0098] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions 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 bridge, characterized in that, include: The outer casing assembly has a hollow space; A motor assembly having a motor output shaft having a first axial through hole, and at least two first bearings being disposed between the motor output shaft and the housing assembly; The transmission mechanism has a power input component, a first power output component, and a second power output component. The motor output shaft, the power input component, the first power output component, and the second power output component are arranged coaxially in sequence. The power input component is provided with a second axial through hole. At least two second bearings are provided between the transmission mechanism and the housing assembly. The first half-shaft passes through the first axial through hole and the second axial through hole, and is coaxially connected to the first power output component. The second half-shaft is coaxially connected to the second power output component; The first support member has a first central hole. The first support member is disposed inside the housing assembly and divides the hollow space to form a motor assembly installation space and a transmission mechanism installation space. The motor output shaft passes through the first central hole and is coaxially arranged with the first central hole. The first central hole is a stepped hole, which includes a first sub-hole, a second sub-hole, and a third sub-hole that are sequentially connected along the axial direction. The diameter of the third sub-hole is larger than the diameter of the second sub-hole, and the diameter of the second sub-hole is larger than the diameter of the first sub-hole. The second bearing is installed in the third sub-hole, and the first bearing is installed in the second sub-hole. The outer diameter of the first half-shaft is larger than the outer diameter of the second half-shaft; The second support member has a second central hole and is mounted on the housing assembly. The first half-shaft coaxially passes through the second central hole. The third bearing is disposed between the wall of the second central hole and the first half-shaft; The second oil seal is located between the wall of the second central hole and the motor output shaft, and the second oil seal is adjacent to the third bearing in the axial direction.

2. The electric drive bridge according to claim 1, characterized in that, The electric drive axle further includes a first oil seal, which seals between the wall of the first central hole and the motor output shaft, and the first oil seal is adjacent to the first bearing mounted on the first support in the axial direction.

3. The electric drive bridge according to claim 1, characterized in that, A gap is formed between the wall of the first axial through hole and the first half-shaft, and the electric drive bridge further includes: The third oil seal is sealed between the hole wall of the second central hole and the first half shaft. The third oil seal is disposed on the side of the third bearing opposite to the motor output shaft and is axially adjacent to the third bearing. The second oil seal is disposed on the side of the third bearing facing the motor output shaft. A fourth oil seal is provided between the housing assembly and the second half-shaft, and the fourth oil seal is axially adjacent to the second bearing disposed between the housing assembly and the second half-shaft, the gap being in communication with the installation space of the transmission mechanism.

4. The electric drive bridge according to claim 1, characterized in that, A gap is formed between the wall of the first axial through hole and the first half-shaft, and the electric drive bridge further includes: The third oil seal is sealed between the second central hole wall and the first half shaft. The third oil seal is disposed on the side of the third bearing opposite to the motor output shaft and is axially adjacent to the third bearing. The second oil seal is disposed on the side of the third bearing facing the motor output shaft. A fourth oil seal is provided between the housing assembly and the second half-shaft, and the fourth oil seal is axially adjacent to the second bearing disposed between the housing assembly and the second half-shaft. The fifth oil seal is disposed within the gap and separates the gap from the installation space of the transmission mechanism.

5. The electric drive bridge according to claim 2, characterized in that, The electric drive axle further includes a second oil seal that seals between the housing assembly and the motor output shaft, and the second oil seal is adjacent to another of the first bearings in the axial direction.

6. The electric drive axle according to any one of claims 1-5, characterized in that, The housing assembly includes a motor housing and a transmission mechanism housing connected together, and the first support member is disposed on the motor housing; or, the housing assembly includes a motor housing and a transmission mechanism housing connected together, and the first support member is disposed on the transmission mechanism housing.

7. The electric drive axle according to any one of claims 1-5, characterized in that: The transmission mechanism includes a planetary transmission mechanism and a differential mechanism that are connected to each other. The power input component is the input component of the planetary transmission mechanism, and the first power output component and the second power output component are both output components of the differential mechanism.

8. A vehicle, characterized in that, Includes the electric drive axle according to any one of claims 1-7.

9. A control method for an electric drive bridge, characterized in that, The electric drive bridge is the electric drive bridge according to any one of claims 1-7, and the method includes: Based on the current accelerator pedal opening range and the preset mapping relationship between the accelerator pedal opening range and the slope, the current slope is determined. The slope is the ratio of the torque of the motor output shaft to the slope of the accelerator pedal opening. In the mapping relationship, the larger the opening value corresponding to the accelerator pedal opening range, the smaller the corresponding slope value. The motor torque is obtained based on the current accelerator pedal opening and the current slope.

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