Drive system, electric machine and transmission for vehicle

Abstract

The utility model discloses a driving system for a vehicle, which comprises a motor and a transmission, the motor comprises a motor shell and a rotor assembly, the rotor assembly is completely or partially installed in the motor shell, and the rotor assembly comprises a rotor shaft; the transmission includes a transmission housing and a speed change mechanism mounted entirely or partially within the transmission housing, the speed change mechanism including an input shaft, in which a first end of a rotor shaft is mounted with a first bearing and attached to the motor housing via the first bearing, and a second end of the rotor shaft extends into the input shaft and is drivingly coupled with the input shaft, a second bearing is mounted on the input shaft, the input shaft is attached to the transmission shell through the second bearing, a first shaft shoulder is formed on the rotor shaft close to the second end, the first shaft shoulder is located outside the input shaft, and the drive system further comprises an elastic element arranged between the end face and the first shaft shoulder. The elastic element is pressed against the end face and the first shaft shoulder respectively to apply axial force to the input shaft and the rotor shaft respectively.

Description

Technical Field

[0001] The utility model relates to the field of automobiles, and in particular to a driving system, a motor and a transmission for a vehicle. Background Art

[0002] As environmental protection issues such as climate warming become increasingly prominent, new energy vehicles represented by electric vehicles have become an important development direction for future vehicles. Electric vehicles use an on-board DC power supply (rechargeable battery) as a power source. The inverter converts the DC power of the on-board DC power supply into AC power and then provides it to the motor. The motor's rotor shaft transmits power to the transmission (such as a reducer) and then drives the wheels. At present, many electric vehicles assemble the inverter, motor and transmission into a whole. Utility Model Content

[0003] The utility model provides a driving system, a motor and a transmission for a vehicle.

[0004] The embodiment of the utility model discloses a driving system for a vehicle, comprising a motor and a transmission, wherein the motor comprises: a motor housing and a rotor assembly, wherein the rotor assembly is wholly or partially mounted in the motor housing, and the rotor assembly comprises a rotor shaft; the transmission comprises: a transmission housing and a speed change mechanism, wherein the speed change mechanism is wholly or partially mounted in the transmission housing, and the speed change mechanism comprises an input shaft, wherein a first bearing is mounted on a first end of the rotor shaft and is attached to the motor housing via the first bearing, a second end of the rotor shaft extends from an end face of the input shaft into the input shaft and is drivingly coupled with the input shaft, a second bearing is mounted near the end face of the input shaft and is attached to the transmission housing via the second bearing, a first shaft shoulder protruding outwardly in the radial direction of the rotor shaft is formed on the rotor shaft near the second end, and the first shaft shoulder is located outside the input shaft, wherein the driving system further comprises an elastic element arranged between the end face and the first shaft shoulder, wherein the elastic element is pressed against the end face and the first shaft shoulder respectively to apply axial forces to the input shaft and the rotor shaft respectively.

[0005] According to another specific embodiment of the present invention, a second shaft shoulder protruding radially outwardly along the rotor shaft is formed on the rotor shaft near the first end, and the inner ring of the first bearing abuts against the second shaft shoulder.

[0006] According to another specific embodiment of the utility model, a first retaining ring is sleeved on the rotor shaft near the first end, and two ends of the inner ring of the first bearing along the axial direction respectively abut against the second shaft shoulder and the first retaining ring.

[0007] According to another specific implementation of the utility model, a second retaining ring is arranged in the motor housing, and the outer ring of the first bearing abuts against the second retaining ring.

[0008] According to another specific embodiment of the present utility model, the elastic element includes a wave spring sleeved on the rotor shaft.

[0009] According to another specific implementation of the present utility model, the motor housing and the transmission housing are fixedly connected.

[0010] An embodiment of the utility model also discloses a motor for a vehicle, comprising: a motor housing; and a rotor assembly, wherein the rotor assembly is wholly or partially installed in the motor housing, and the rotor assembly includes a rotor shaft, wherein a first bearing is installed on a first end of the rotor shaft and is attached to the motor housing via the first bearing, and a second end of the rotor shaft extends from an end face of an input shaft of a transmission for the vehicle into the input shaft and is drivingly connected to the input shaft, and a first shoulder protruding radially outward along the rotor shaft is formed on the rotor shaft near the second end, and the first shoulder is located outside the input shaft, wherein the motor also includes a wave spring sleeved on the rotor shaft, and the wave spring is used to press against the end face and the first shoulder respectively when the motor is assembled to the transmission to apply axial force to the input shaft and the rotor shaft respectively.

[0011] According to another specific embodiment of the present invention, a second shaft shoulder protruding radially outwardly along the rotor shaft is formed on the rotor shaft near the first end, and the inner ring of the first bearing abuts against the second shaft shoulder.

[0012] According to another specific embodiment of the utility model, a first retaining ring is sleeved on the rotor shaft near the first end, and two ends of the inner ring of the first bearing along the axial direction respectively abut against the second shaft shoulder and the first retaining ring.

[0013] According to another specific implementation of the utility model, a second retaining ring is arranged in the motor housing, and the outer ring of the first bearing abuts against the second retaining ring.

[0014] An embodiment of the utility model also discloses a transmission for a vehicle, comprising: a transmission housing; and a speed shifting mechanism, wherein the speed shifting mechanism is wholly or partially installed in the transmission housing, the speed shifting mechanism comprising an input shaft, wherein a second bearing is installed on the input shaft and is attached to the transmission housing via the second bearing, the input shaft is formed with a cavity for receiving the end of a rotor shaft of a motor for the vehicle, wherein the transmission also includes a wave spring arranged at the end face of the input shaft, the wave spring is used to press against the end face and the shoulder of the rotor shaft respectively when the transmission is assembled to the motor to apply axial force to the input shaft and the rotor shaft respectively.

[0015] By adopting the above technical solution, an elastic element, such as a wave spring, is arranged between the end face of the input shaft of the transmission and the shoulder of the rotor shaft of the motor. The elastic element can apply axial force to the input shaft of the transmission and the rotor shaft of the motor respectively, thereby applying preload force to the bearings on the motor side and the bearings on the transmission side at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic cross-sectional view showing the cooperation between the shaft and the bearing;

[0017] Figure 2 A cross-sectional view showing a conventional drive system for a vehicle at a motor;

[0018] Figure 3 A cross-sectional view of a driving system for a vehicle at a motor according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0019] The following is an explanation of the implementation of the present invention by specific specific embodiments. Those skilled in the art can easily understand other advantages and functions of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this utility model are limited to this implementation. On the contrary, the purpose of introducing the utility model in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that, in the absence of conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0020] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0021] In the description of this embodiment, unless otherwise specified, the terms "front", "rear", "up", "down", "top", "bottom", etc. indicating directions or positional relationships are based on the directions or positional relationships indicated in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0022] The terms “first”, “second”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0023] In the description of this embodiment, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "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 an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this embodiment can be understood according to specific circumstances.

[0024] In order to make the purpose, technical solution and advantages of the present invention more clear, the implementation mode of the present invention will be further described in detail below with reference to the accompanying drawings.

[0025] refer to Figure 1 , is a schematic cross-sectional view of the shaft 100 and the bearing 200. The figure shows a rolling bearing, whose inner ring 210 is interference-fitted with the shaft 100 to rotate with the shaft 100; the outer ring 220 is usually matched with the bearing seat hole or the housing of the mechanical component to play a supporting role; the rolling element 230 is arranged between the inner ring 210 and the outer ring 220. Under the action of gravity, the rolling element 230 will be closer to the bearing ring located below. For example, in the upper part of the bearing 200, the rolling element 230 is closer to the inner ring 210 so that a gap 300 appears between it and the outer ring 220; and in the lower part of the bearing 200, the rolling element 230 is closer to the outer ring 220 so that a gap 300 appears between it and the inner ring 210. Such a gap 300 will cause undesirable vibration, which is not conducive to high-speed and stable operation. An axial force F (hereinafter referred to as a "preload force" applied to the bearing) may be applied to the inner ring 210 of the bearing 200, for example. Figure 1As shown, the inner ring 210 of the bearing 200 is slightly axially displaced relative to the outer ring 220, thereby achieving a close fit between the rolling element 230 and the inner and outer rings. Figure 1 The preload force shown is applied to the bearing inner ring 210, and it should be understood that in other examples the preload force can be applied to the bearing outer ring 220. Figure 1 The preload force shown is in the first direction (in axial direction) Figure 1 The viewing direction is to the left), it should be understood that in other examples the preload force may be axially directed in a second direction opposite to the first direction.

[0026] Figure 2 : is a cross-sectional view of an existing drive system for a vehicle at the motor. The drive system includes a motor, a rotor 400 of the motor is mounted on a rotor shaft 500, and the rotor shaft 500 is attached to a motor housing 800 via a motor-side bearing 600. The drive system also includes a wave spring 700 installed in the motor housing 800 for applying a preload force to the motor-side bearing 600, one end of the wave spring 700 is pressed against the motor housing 800, and the other end is pressed against the outer ring of the motor-side bearing 600, so as to apply a preload force to the outer ring of the motor-side bearing 600. In this existing solution, there is a risk of interference between the wave spring 700 and the inner ring of the motor-side bearing 600 during assembly and operation, for example, the wave spring 700 may enter between the inner ring and the outer ring of the motor-side bearing 600 and interfere with the movement of the rolling body, or contact the inner ring of the motor-side bearing 600 and interfere with the rotation of the inner ring, etc. In addition, since there is no assembly relationship between the wave spring 700 and the rotor shaft 500 , it is inconvenient to disassemble and assemble the wave spring 700 , and the components may be damaged during disassembly.

[0027] In order to solve the above technical problems, the embodiments of the present utility model provide a driving system for a vehicle, such as Figure 3 As shown. A drive system for a vehicle according to an embodiment of the utility model includes a motor and a transmission (such as a reducer). Among them, the motor includes a motor housing 11 and a rotor assembly, and the rotor assembly includes a rotor shaft 12. The rotor assembly is fully or partially installed in the motor housing 11. The transmission includes a transmission housing 21 and a speed change mechanism, and the speed change mechanism includes an input shaft 22. The speed change mechanism is fully or partially installed in the transmission housing 21. Typically, the motor housing 11 and the transmission housing 21 are fixedly connected. In a specific example, the motor housing 11 has an opening (not shown), and the transmission housing 21 covers the opening of the motor housing 11.

[0028] The first end 121 of the rotor shaft 12 is installed with a first bearing 31, and the first end 121 of the rotor shaft 12 is attached to the motor housing 11 via the first bearing 31. The second end 122 of the rotor shaft 12 extends from the end face 221 of the input shaft 22 of the transmission (i.e., the end face of the input shaft 22 facing the motor side) to the input shaft 22, and the second end 122 is drivingly connected to the input shaft 22. A second bearing 32 is installed near the end face 221 of the input shaft 22, so that the input shaft 22 is attached to the transmission housing 21 via the second bearing 32. A first shoulder 123 is formed on the rotor shaft 12 near the second end 122. The first shoulder 123 extends along the circumference of the rotor shaft 12 and protrudes outward in the radial direction of the rotor shaft 12. In addition, the first shoulder 123 is located outside the input shaft 22, that is, it does not extend into the interior of the input shaft 22. The drive system according to an embodiment of the utility model also includes an elastic element 40 arranged between the end face 221 of the input shaft 22 and the first shoulder 123. The elastic element 40 presses against the end surface 221 of the input shaft 22 and the first shoulder 123 respectively, so as to apply axial forces, ie, forces F1 and F2 in opposite axial directions, to the input shaft 22 and the rotor shaft 12 respectively.

[0029] The input shaft 22 of the transmission has an interference fit with the inner ring of the second bearing 32, and the outer ring of the second bearing 32 has an interference fit with the transmission housing 21. Therefore, the force F1 applied by the elastic element 40 to the input shaft 22 in the axial direction toward the first direction will be transmitted to the inner ring of the second bearing 32 via the input shaft 22, so that the inner ring of the second bearing 32 has a small displacement in the first direction relative to its outer ring, thereby making the rolling element of the second bearing 32 fit closely with its inner ring and outer ring. The rotor shaft 12 of the motor has an interference fit with the inner ring of the first bearing 31, and the outer ring of the first bearing 31 has an interference fit with the motor housing 11. Therefore, the force F2 applied by the elastic element 40 to the rotor shaft 12 in the axial direction toward the second direction opposite to the first direction will be transmitted to the inner ring of the first bearing 31 via the rotor shaft 12, so that the inner ring of the first bearing 31 has a small displacement in the second direction relative to its outer ring, thereby making the rolling element of the first bearing 31 fit closely with its inner ring and outer ring. In this way, the elastic element 40 installed between the end face 221 of the input shaft 22 and the first shoulder 123 can simultaneously realize the preload of the first bearing 31 on the motor side and the second bearing 32 on the transmission side. In addition, the elastic element 40 does not directly contact the first bearing 31 or the second bearing 32, avoiding the risk of interfering with the movement of the bearings.

[0030] In a specific example, the elastic element 40 may be a wave spring sleeved on the rotor shaft 12. The wave spring is sleeved on the rotor shaft 12 and pressed between the end face 221 of the input shaft 22 and the first shoulder 123 to facilitate positioning and disassembly.

[0031] In a specific example, a second shoulder 124 is formed on the rotor shaft 12 near the first end 121. The second shoulder 124 extends along the circumference of the rotor shaft 12 and protrudes outward in the radial direction of the rotor shaft 12. The inner ring of the first bearing 31 abuts the second shoulder 124. The second shoulder 124 can be used to limit the position of the first bearing 31 during the process of pressing the first bearing 31 onto the rotor shaft 12. For example, when installing the first bearing 31, it is only necessary to press the inner ring of the first bearing 31 to fit the second shoulder 124. If there is no second shoulder 124, it is necessary to rely on tooling to ensure the installation position of the first bearing 31, otherwise once the first bearing 31 is pressed over the position, it will cause damage to the rotor. In addition, the second shoulder 124 can also be used to transfer the force applied by the elastic element 40 to the rotor shaft 12 to the first bearing 31. That is, the force F2 in the second axial direction applied by the elastic element 40 to the rotor shaft 12 is transmitted to the inner ring of the first bearing 31 due to the interference fit between the rotor shaft 12 and the first bearing 31 and the second shaft shoulder 124. In this way, the interference between the first bearing 31 and the rotor shaft 12 does not need to be too large, which can facilitate the installation of the first bearing 31 and help extend the service life of the first bearing 31.

[0032] In a specific example, a first retaining ring 51 is sleeved on the rotor shaft 12 near the first end 121. An annular groove (not shown) cooperating with the first retaining ring 51 is provided at a corresponding position of the rotor shaft 12, and the first retaining ring 51 is installed in the annular groove to limit the axial movement of the inner ring of the first bearing 31 in the second direction. In addition, as shown in the figure, the inner ring of the first bearing 31 abuts against the second shoulder 124 and the first retaining ring 51 at both ends along the axial direction. In a specific example, an annular groove (not shown) cooperating with the second retaining ring 52 is provided in the motor housing 11, and the second retaining ring 52 is installed in the annular groove to limit the axial movement of the outer ring of the first bearing 31 in the first direction. The coordinated use of the first retaining ring 51 and the second retaining ring 52 can limit the axial movement of the rotor shaft 12, such as the relative displacement between the rotor shaft 12 and the first bearing 31 in the axial direction caused by a strong axial impact.

[0033] The embodiment of the utility model also proposes a motor for a vehicle. The motor according to the embodiment of the utility model includes a motor housing 11 and a rotor assembly. The rotor assembly is installed in the motor housing 11 in whole or in part. The rotor assembly includes a rotor shaft 12, and the first end 121 of the rotor shaft 12 is installed with a first bearing 31 and attached to the motor housing 11 via the first bearing 31. The second end 122 of the rotor shaft 12 extends from the end face 221 of the input shaft 22 of the transmission for the vehicle into the input shaft 22 and is drivingly connected with the input shaft 22. A first shoulder 123 is formed on the rotor shaft 12 near the second end 122, and the first shoulder 123 is located outside the input shaft 22. The motor also includes a wave spring sleeved on the rotor shaft 12, and the wave spring is used to press against the end face 221 and the first shoulder 123 respectively when the motor is assembled to the transmission to apply axial force to the input shaft 22 and the rotor shaft 12 respectively. In some specific examples, a second shaft shoulder 124 is formed on the rotor shaft 12 near the first end 121, and the inner ring of the first bearing 31 abuts against the second shaft shoulder 124. A first retaining ring 51 is sleeved on the rotor shaft 12 near the first end 121, and the inner ring of the first bearing 31 abuts against the second shaft shoulder 124 and the first retaining ring 51 at both ends along the axial direction. A second retaining ring 52 is arranged in the motor housing 11, and the outer ring of the first bearing 31 abuts against the second retaining ring 52.

[0034] The embodiment of the utility model also proposes a transmission for a vehicle. The transmission according to the embodiment of the utility model includes a transmission housing 21 and a speed change mechanism. The speed change mechanism is fully or partially installed in the transmission housing 21. The speed change mechanism includes an input shaft 22, on which a second bearing 32 is installed and attached to the transmission housing 21 via the second bearing 32. The input shaft 22 is formed with a cavity for receiving the end of the rotor shaft 12 of the motor for the vehicle. The transmission also includes a wave spring arranged at the end face 221 of the input shaft 22, and the wave spring is used to press against the end face 221 and the shoulder 123 of the rotor shaft 12 respectively when the transmission is assembled to the motor to apply axial force to the input shaft 22 and the rotor shaft 12 respectively.

[0035] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above contents are further detailed descriptions of the present invention in combination with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A drive system for a vehicle, characterized in that: It includes a motor and a transmission, wherein: The motor comprises: a motor housing and a rotor assembly, wherein the rotor assembly is fully or partially installed in the motor housing, and the rotor assembly comprises a rotor shaft; The transmission comprises: a transmission housing and a speed change mechanism, wherein the speed change mechanism is fully or partially installed in the transmission housing, and the speed change mechanism comprises an input shaft, wherein: The first end of the rotor shaft is installed with a first bearing and is attached to the motor housing via the first bearing, and the second end of the rotor shaft extends from the end surface of the input shaft into the input shaft and is drivingly coupled to the input shaft. The input shaft is provided with a second bearing near the end surface and is attached to the transmission housing via the second bearing. A first shaft shoulder protruding outwardly in the radial direction of the rotor shaft is formed on the rotor shaft near the second end portion, and the first shaft shoulder is located outside the input shaft. Wherein, the drive system further comprises an elastic element arranged between the end face and the first shaft shoulder, and the elastic element is pressed against the end face and the first shaft shoulder respectively to apply axial force to the input shaft and the rotor shaft respectively.

2. The drive system according to claim 1, characterized in that: A second shaft shoulder protruding outwardly in the radial direction of the rotor shaft is formed on the rotor shaft near the first end portion, and the inner ring of the first bearing abuts against the second shaft shoulder.

3. The drive system according to claim 2, characterized in that: A first retaining ring is sleeved on the rotor shaft near the first end portion, and two ends of the inner ring of the first bearing along the axial direction respectively abut against the second shaft shoulder and the first retaining ring.

4. The drive system according to claim 1, characterized in that: A second retaining ring is arranged in the motor housing, and the outer ring of the first bearing abuts against the second retaining ring.

5. The drive system according to claim 1, characterized in that: The elastic element comprises a wave spring sleeved on the rotor shaft.

6. The drive system according to claim 1, characterized in that: The motor housing and the transmission housing are fixedly connected.

7. A motor for a vehicle, characterized in that: include: Motor housing; and A rotor assembly, the rotor assembly is fully or partially mounted in the motor housing, the rotor assembly includes a rotor shaft, wherein: The first end of the rotor shaft is mounted with a first bearing and is attached to the motor housing via the first bearing, The second end of the rotor shaft extends from the end face of the input shaft of the transmission for the vehicle into the input shaft and is drivingly coupled to the input shaft. A first shaft shoulder protruding outwardly in the radial direction of the rotor shaft is formed on the rotor shaft near the second end portion, and the first shaft shoulder is located outside the input shaft. Wherein, the motor further comprises a wave spring sleeved on the rotor shaft, and the wave spring is used to press against the end face and the first shaft shoulder respectively to apply axial force to the input shaft and the rotor shaft respectively when the motor is assembled to the transmission.

8. The motor according to claim 7, characterized in that A second shaft shoulder protruding outwardly in the radial direction of the rotor shaft is formed on the rotor shaft near the first end portion, and the inner ring of the first bearing abuts against the second shaft shoulder.

9. The motor according to claim 8, characterized in that A first retaining ring is sleeved on the rotor shaft near the first end portion, and two ends of the inner ring of the first bearing along the axial direction respectively abut against the second shaft shoulder and the first retaining ring.

10. The motor according to claim 7, characterized in that A second retaining ring is arranged in the motor housing, and the outer ring of the first bearing abuts against the second retaining ring.

11. A transmission for a vehicle, characterized in that: include: Transmission housing; and A speed change mechanism, the speed change mechanism is fully or partially installed in the transmission housing, the speed change mechanism includes an input shaft, wherein: The input shaft has a second bearing mounted thereon and is attached to the transmission housing via the second bearing, The input shaft is formed with a cavity for receiving an end of a rotor shaft of an electric machine for the vehicle, The transmission further comprises a wave spring arranged at the end face of the input shaft, and the wave spring is used to press against the end face and the shoulder of the rotor shaft respectively to apply axial force to the input shaft and the rotor shaft respectively when the transmission is assembled to the motor.

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