CN118174500A - Motor, power assembly and electric vehicle - Google Patents

Abstract

The application provides a motor with a motor shaft conductive structure, which comprises a shell, a stator, a rotor, a motor shaft and a conductive structure, wherein the shell of the motor is used for accommodating the stator and the rotor of the motor, the conductive structure is used for electrically connecting the motor shaft and the shell, and the conductive structure comprises a conductor, a conductive column and a conductive brush. The electric conductor is embedded into the axial inner cavity of the motor shaft, one end of the electric conduction column is fixedly connected with the shell, the other end of the electric conduction column stretches into the axial inner cavity of the motor shaft, one end of the electric conduction brush is fixedly connected with the other end of the electric conduction column, and the other end of the electric conduction brush contacts the electric conductor. Wherein the hardness of the conductive brush is less than the hardness of the conductor. Because the hardness of the conductive brush is smaller than that of the conductor, the conductive brush and the conductor can be rotationally connected, and the conductive bearing is omitted. So set up, conductive structure's subassembly is few, simple structure need not too high location and precision requirement, and conductive performance is good, and the reliability is high.

Description

Motor, power assembly and electric vehicle

Technical Field

The application relates to the technical field of electric automobiles, in particular to a motor, a power assembly and an electric automobile.

Background

In the working process of the driving motor of the electric vehicle, shaft voltage can be formed on a motor shaft. If the shaft voltage exceeds the breakdown threshold of lubricating grease in the rotating shaft bearing, partial discharge can occur between the rolling body and the rollaway nest of the rotating shaft bearing, so that an electric melting pit is formed on the rollaway nest, and the phenomenon of electric erosion of the rotating shaft bearing occurs. The electric erosion of the rotating shaft bearing can aggravate the damage of the rotating shaft bearing, so that the rotating shaft bearing generates specific order noise and high-frequency noise, the riding comfort of the whole vehicle is affected slightly, and the rotating shaft bearing is damaged and power is interrupted seriously.

Disclosure of Invention

The application provides a motor with a motor shaft conductive structure, a power assembly and an electric vehicle, which can avoid the bearing electric erosion phenomenon and ensure the reliability of a rotating shaft bearing.

In a first aspect, the application provides an electric motor with a motor shaft conductive structure, comprising a housing, a stator, a rotor, a motor shaft and a conductive structure, wherein the housing of the electric motor is used for accommodating the stator and the rotor of the electric motor, the conductive structure is used for electrically connecting the motor shaft and the housing, and the conductive structure comprises a conductor, a conductive column and a conductive brush. Wherein, the electric conductor embeds the axial inner chamber of motor shaft, and the one end fixed connection casing of conducting post, the other end of conducting post stretches into the axial inner chamber, and the other end of conducting brush, the other end contact electric conductor of one end fixed connection conducting post of conducting brush. Wherein the hardness of the conductive brush is less than the hardness of the conductor. Specifically, to avoid the electrical corrosion of the shaft bearings caused by the overpressure of the motor shaft, it is necessary to add a conductive structure to the motor. In the application, the conductor is embedded into the axial inner cavity and rotates along with the motor shaft, and the hardness of the conductive brush is smaller than that of the conductor, so that the conductive brush and the conductor can realize rotary contact, and the arrangement of the conductive bearing can be omitted. In practical applications, the conductive brush is usually made of flexible conductive materials with better wear resistance and high temperature resistance, such as carbon fiber, and the conductive body and the conductive post are usually made of rigid conductive materials, such as metal or alloy, in order to ensure the stability of the relative positions between the conductive structure and the casing. In the process that the conductor rotates along with the motor shaft, the flexible conductive brush can well realize stable electric connection between two rigid materials, namely the conductor and the conductive column. In other words, since the conductive brush is a flexible material, structural failure of the conductive brush is not generally caused even if the conductive brush is deformed, bent or compressed by contact with the rotating conductive body during rotation of the conductive body. The arrangement greatly simplifies the component composition of the conductive structure, and particularly, the arrangement of the conductive bearing can be omitted, so that special size and positioning design of an axial inner cavity of a motor shaft for fixing the conductive bearing are not needed. In addition, because one end of the conductive brush is fixedly connected with the conductive column, and the other end of the conductive brush is in contact with the conductive body, the deformation of the conductive brush caused by the rotation of the motor shaft can be avoided, and the conductive stability of the conductive structure is improved.

In one possible embodiment, the hardness of the conductive brush is less than the hardness of the conductive post. By the arrangement, the conductive brush can be better fixed on the conductive column, so that the conductive brush is prevented from being synchronously driven to rotate when the conductive body rotates, and the conductive reliability of the conductive structure is improved. As described above, during operation of the motor, the conductive body rotates with the motor shaft, and the conductive post is stationary with respect to the housing due to the fixation to the housing. On the basis, since the hardness of the conductive post is larger than that of the conductive brush, even if the conductive brush is deformed, bent or compressed due to contact with the rotating conductive body, the conductive post is not affected, that is, the conductive post can still keep the relative position of the conductive post and the shell stable, and the conductive reliability of the conductive structure is further improved.

In one possible embodiment, the electrical conductor comprises a floor recessed toward the conductive brush. That is, the portion of the conductor in contact with the conductive brush is concave. By the arrangement, good electric contact can be still kept after the conductive brush and the conductive body are axially contacted and deformed, and the reliability and stability of the conductive structure are improved.

In one possible embodiment, the electrical conductor includes a rim surrounding an edge of the connection floor, the rim having an outer diameter that is not less than an inner diameter of the axial cavity. On the one hand, through the setting of frame, can increase the area of contact of the inner wall of electric conductor and axial inner chamber, on the other hand, when the external diameter of frame is not less than the internal diameter of axial inner chamber, also can realize better fixing between electric conductor and the axial inner chamber, and then guarantee the stability of electric conductor and conducting brush relative position.

In one possible embodiment, the electrical conductor is arranged coaxially with the motor shaft and the electrical conductor brush is arranged coaxially with the motor shaft. By the arrangement, the conductive brush and the conductive body can be ensured to axially contact rather than radially contact, and the friction loss between the conductive body and the conductive brush is small due to small linear speed near the axis, so that the stability and reliability of the conductive structure are improved.

In one possible embodiment, one end of the conductive post includes an oil baffle, and the radial oil baffle along the motor shaft is sized not smaller than the inner diameter of the axial lumen. The motor in the application can be an oil-cooled motor, namely, cooling oil is adopted for cooling and radiating. The cooling oil can flow in the shell and the axial inner cavity to realize cooling and heat dissipation. Through the setting of oil baffle, can form partial sealed space in axial inner chamber, this sealed space is enclosed by electric conductor, oil baffle and the partial inner wall of axial inner chamber and is established. The conducting brush is positioned in the sealed space, so that the conducting brush can work in an oil-free environment, and reliable conduction between the conducting brush and the conductor is ensured.

In one possible embodiment, one end of the conductive post includes a connecting arm, the connecting arm extends along a radial direction of the motor shaft, one end of the connecting arm is connected with the casing, the other end of the connecting arm is connected with the oil baffle, and the connecting arm is in radial divergent distribution. So set up, improved the joint strength between one end of conductive post and the casing, improved conductive structure's stability and reliability. In addition, the connecting arm structure of the structure is reliable, small in occupied space, capable of being used for supporting other parts and good in reusability.

In one possible embodiment, the motor includes a resolver stator, the resolver stator is annular, the resolver stator is fixed inside the casing, the resolver stator and the oil baffle are both coaxially disposed with the motor shaft, and the diameter of the outer ring of the resolver stator is less than or equal to the size of the radial oil baffle along the motor shaft. By the arrangement, the cooling oil outside the shell can be prevented from splashing to the rotary transformer stator, and the working stability of the rotary transformer stator is improved.

In one possible embodiment, the motor includes a resolver stator, a pressing plate and a fixing member, the resolver stator is annular, the resolver stator is fixed inside the casing, the pressing plate is located between the connecting arm and the casing along the axial direction of the motor shaft, the pressing plate is clamped with the outer ring of the resolver stator, and the fixing member is used for fixing the pressing plate and the connecting arm to the casing. By the arrangement, the stator of the rotary transformer is ensured to be stably fixed on the shell, and reliable conductive connection between the connecting arm and the shell is ensured.

In one possible embodiment, the other end of the conductive post includes a groove, and the groove at the other end of the conductive post is snapped into the conductive brush. By the arrangement, stable connection of the conductive brush and the conductive column can be realized, and further the working reliability of the conductive structure is improved.

In one possible embodiment, the length of the conductive brush is greater than the distance between the other end of the conductive post and the electrical conductor along the axial direction of the motor shaft. Specifically, friction exists between the conductor and the conductive brush during rotation of the conductor along with the motor shaft, so that the conductive brush gradually wears out over time, and the size of the conductive brush becomes shorter, and good contact between the conductive brush and the conductor cannot be achieved. In the application, because the length of the conductive brush is longer than the distance between the other end of the conductive post and the conductor along the axial direction of the motor shaft, even if the conductive brush is worn, the conductive brush and the conductor can still keep good electric contact, and the working reliability of the conductive structure is ensured.

In one possible embodiment, the conductive brush extends in an axial direction of the motor shaft, and the size of the conductive brush in a radial direction of the motor shaft is smaller than the size of the electrical conductor. By the arrangement, the contact area between the conductive brush and the conductor can be reduced, so that the friction loss of the conductive brush is reduced, and good electrical contact between the conductive brush and the conductor can be ensured.

In one possible embodiment, the dimension of the other end of the conductive post in the radial direction of the motor shaft is smaller than the dimension of the electrical conductor. The arrangement is that the space occupied by the other end of the conductive column is small, but the conductive column can stably support the conductive brush.

In a second aspect, the present application provides a powertrain comprising a motor of the motor shaft conductive structure of any one of the first aspects and a motor controller for controlling operation of the motor shaft conductive structure.

In a third aspect, the present application provides an electric vehicle comprising the powertrain of the second aspect and a frame, the powertrain being mounted to the frame.

In general, when the motor shaft rotates and generates a shaft voltage, the shaft current may be conducted along the following path: the motor shaft, the conductive brush, the conductive column, the machine shell and the ground. Therefore, the scheme of the application can release the shaft voltage on the motor shaft to the ground, and cannot cause bearing electric corrosion of the rotating shaft bearing. In addition, the conductive structure comprises fewer parts, omits the arrangement of the conductive bearing, has a simple structure, can realize reliable matching with the axial inner cavity of the motor shaft without complex positioning, and has higher reliability and better conductive performance.

Drawings

Fig. 1 is a schematic structural diagram of an electric vehicle;

FIG. 2 is a schematic block diagram of a powertrain of an electric vehicle provided by the present application;

FIG. 3 is a schematic perspective view of a motor in a powertrain according to the present application;

FIG. 4 is a schematic cross-sectional view of the motor of FIG. 3;

FIG. 5 is a schematic diagram of a perspective assembly structure of the conductive structure of FIG. 4;

FIG. 6 is an exploded view of the conductive structure of FIG. 4;

FIG. 7 is a schematic cross-sectional view of the assembled structure of FIG. 5;

fig. 8 is a schematic diagram of a matching structure of the pressing plate and the motor in fig. 4.

Detailed Description

The present embodiment provides an electric vehicle, such as an electric SUV (Sport Utility Vehicle, sports utility vehicle) 10, schematically illustrated in FIG. 1. The electric vehicle 10 includes a frame and a powertrain 11 (not shown) mounted to the frame. The frame is used as a structural framework of the electric vehicle and is used for supporting, fixing and connecting each assembly to bear the load of the inside and outside environment of the automobile system.

The present embodiment also provides a powertrain 11, the powertrain 11 being a system of a series of components for generating and transmitting power to a road surface. As shown in fig. 2, the powertrain 11 includes a motor controller 12 and a motor 13. The motor controller 12 is electrically connected with the motor 13 and is used for controlling the motor 13 to work.

Referring to fig. 3 and 4 (fig. 3 is a schematic perspective view of the motor 13 in the powertrain 11, and fig. 4 is a schematic sectional view of the motor 13 shown in fig. 3, wherein the sectional view is parallel to the paper surface), the motor 13 of the present embodiment includes a housing 131, a stator (not shown), a rotor (not shown), a motor shaft 132, a shaft bearing 141, and a conductive structure. The casing 131 serves to accommodate the above-described stator and rotor. The motor shaft 132 and the shaft bearing 141 are mounted on the housing 131. Wherein, a part of the motor shaft 132 is located inside the housing 131, another part of the motor shaft 132 extends outside the housing 131, and the exposed part of the motor shaft 132 may be used as an output end, and an end opposite to the output end may be referred to as a positioning end. The positioning end may be located within the housing 131. The rotation shaft bearings 141 may be, for example, two, and are respectively installed at both sides of the casing 131. The motor shaft 132 is rotated with respect to the housing 131 through a rotation shaft bearing 141.

In this embodiment, the specific structures of the casing 131, the motor shaft 132 and the rotating shaft bearing 141, and the positions of the motor shaft 132 and the rotating shaft bearing 141 on the casing 131 may be designed according to actual needs, and the embodiment is not limited.

Referring to fig. 4, the motor shaft 132 includes an axial inner cavity 132a, and the axial inner cavity 132a penetrates the motor shaft 132 in the axial direction of the motor shaft 132. The inner wall of the axial cavity 132a may be, for example, a cylindrical surface. The motor 13 of the present embodiment may be an oil-cooled motor, i.e., it is cooled by cooling oil. The cooling oil can flow in the casing 131 and in the axial inner chamber 132a, thereby realizing cooling and heat dissipation.

With continued reference to fig. 4, the motor 13 further includes an electrically conductive structure for electrically connecting the motor shaft 132 and the housing 131. Specifically, the conductive structure includes a conductive body 133, a conductive brush 134, and a conductive post 135. Wherein, the electric conductor 133 is embedded in the axial inner cavity 132a and rotates along with the motor shaft 132, one end 135a of the electric conductive post (including the oil baffle 135a1 and the connecting arm 135a2, which will be described in detail below) is fixedly connected to the casing 131, the other end 135b of the electric conductive post (including the first portions 135b1 and 135b2, which will be described in detail below) extends into the axial inner cavity 132a, one end of the electric conductive brush 134 is fixedly connected to the other end 135b of the electric conductive post, and the other end of the electric conductive brush 134 is in contact with the electric conductor 133. By providing the conductive structure, the shaft current of the motor shaft 132 can be timely conducted to the ground, thereby avoiding the electric corrosion of the rotating shaft bearing 141 caused by the overvoltage of the motor shaft 132. It should be noted that, in the present embodiment, the hardness of the conductive brush 134 is smaller than that of the conductive body 133. In practical applications, the conductive brush 134 is generally made of flexible conductive material with better wear resistance and high temperature resistance, such as carbon fiber, and the conductive body 133 and the conductive brush 135 are generally made of rigid conductive material, such as metal or alloy, to ensure the stability of the relative position between the conductive structure and the housing 131. The flexible conductive brush 134 can well achieve a stable electrical connection between two rigid materials, namely the conductive brush 135 and the conductive body 133, during rotation of the conductive body 133 with the motor shaft 132. In other words, since the conductive brush 134 is a flexible material, structural failure of the conductive brush 134 is not generally caused even if the conductive brush 134 is deformed, bent or compressed by contact with the rotating conductive body 133 during rotation of the conductive body 133 with the motor shaft 132. By the arrangement, the component composition of the conductive structure is greatly simplified, and particularly, the arrangement of the conductive bearing can be omitted, so that the special size and positioning design of the axial inner cavity 132a of the motor shaft 132 for fixing the conductive bearing are not needed. The conductive bearing is a component responsible for transmitting electric energy or signals to the rotating structure, and generally comprises a rotating part and a stationary part, wherein the rotating part is used for being connected with the rotating structure and rotating along with the rotating structure, and the stationary part is used for being connected with a fixed structure of the equipment. For example, when the conductive bearing is applied to a fan, the blades of the fan are continuously rotated, and the wire is required to be connected to the rotating structure, in which case the conductive bearing is required to be introduced in order to avoid winding of the wire. Similarly, in the electric automobile field, in order to timely guide the shaft current of the motor shaft 132 to the ground, it is generally necessary to introduce a conductive bearing, but the introduction of a conductive bearing increases the cost of components on the one hand, and on the other hand, in order to adapt to the size of the conductive bearing, the axial cavity 132a also needs to be adaptively sized, increasing the complexity of processing and assembly.

As described above, the hardness of the conductive brush 134 is also smaller than the hardness of the conductive post 135. By the arrangement, the conductive brush 134 can be better fixed on the conductive post 135, so that the conductive brush 134 is prevented from being synchronously driven when the conductive body 133 rotates, and the conductive reliability of the conductive structure is improved. As described above, during operation of the motor 13, the conductive body 133 rotates with the motor shaft 132, and the conductive post 135 is stationary with respect to the housing 131 due to being fixed to the housing 131. On this basis, since the hardness of the conductive post 135 is greater than that of the conductive brush 134, even if the conductive brush 134 is deformed, bent or compressed by contact with the rotating conductive body 133, the conductive post 135 is not affected, that is, the conductive post 135 can maintain a stable position with respect to the housing 131, thereby improving the conductive reliability of the conductive structure.

With continued reference to fig. 4, the electrical conductor 133 is disposed coaxially with the motor shaft 132 and the electrical conductor brush 134 is disposed coaxially with the motor shaft 132. By the arrangement, the conductive brush 134 and the conductive body 133 can be ensured to axially contact rather than radially contact, and the friction loss between the conductive body 133 and the conductive brush 134 is small due to the small linear speed near the axis, so that the stability and reliability of the conductive structure are improved.

In practical application, the length of the conductive brush 134 is longer than the distance between the other end 135b of the conductive post and the conductive body 133 along the axial direction of the motor shaft 132. Specifically, during the rotation of the conductive body 133 along with the motor shaft 132, friction exists between the conductive body 133 and the conductive brush 134, so that the conductive brush 134 gradually wears with the lapse of time, and the size of the conductive brush 134 becomes shorter, and good contact between the conductive brush 134 and the conductive body 133 cannot be achieved. In this embodiment, since the length of the conductive brush 134 is longer than the distance between the other end 135b of the conductive post and the conductive body 133 along the axial direction of the motor shaft 132, even if the conductive brush 134 is worn, good electrical contact can be maintained between the conductive brush 134 and the conductive body 133, and the operational reliability of the conductive structure is ensured.

With continued reference to fig. 4, the conductive brush 134 extends in the axial direction of the motor shaft 132, and the size of the conductive brush 134 in the radial direction of the motor shaft 132 is smaller than the size of the conductive body 133. By the arrangement, the contact area between the conductive brush 134 and the conductive body 133 can be reduced, so that the friction loss of the conductive brush 134 is reduced, and good electrical contact between the conductive brush 134 and the conductive body 133 can be ensured.

With continued reference to fig. 4, the other end 135b of the conductive post includes a first portion 135b1 and a second portion 135b2, wherein the first portion 135b1 is approximately cylindrical and is connected between the first portion 135b1 and the one end 135a of the conductive post, and the second portion 135b2 is approximately groove-shaped for holding the conductive brush 134.

With continued reference to fig. 4, the dimension of the other end 135b of the conductive post along the radial direction of the motor shaft 132 is smaller than the dimension of the conductive body 133. So arranged, the other end 135b of the conductive post occupies a small space, but the other end 135b of the conductive post can still stably support the conductive brush 134.

Referring to fig. 4 to 7 (fig. 5 is a schematic perspective assembly view of the conductive structure of fig. 4, fig. 6 is a schematic exploded view of the conductive structure of fig. 4, and fig. 7 is a schematic cross-sectional view of the assembly structure of fig. 5), the conductive body 133 includes a bottom plate 1331 recessed toward the conductive brush 134 and a rim 1332 surrounding an edge of the bottom plate 1331, that is, the conductive body 133 is approximately bowl-shaped as a whole. Specifically, by providing the bottom plate 1331 in a recessed shape, good electrical contact between the conductive brush 134 and the conductive body 133 can be maintained after the conductive brush and the conductive body are deformed by axial contact, and thus reliability and stability of the conductive structure can be improved. In other words, the concave bottom plate 1331 has a certain limiting effect on the conductive brush 134, and even if the conductive brush 134 is deformed, the bottom plate 1331 can gather the conductive brush 134, so that good electrical contact between the conductive brush 134 and the conductive body 133 is ensured. By providing the rim 1332, the contact area of the conductor 13 with the inner wall of the axial cavity 132a can be increased. In addition, the outer diameter of the rim 1332 is not smaller than the inner diameter of the axial cavity 132a, that is, the rim 1332 forms an interference fit with the axial cavity 132a to closely fit and form a connection with the axial cavity 132 a.

It should be noted that, when the motor 13 is an oil-cooled motor, the electrical conductor 133 can be reused as an oil plug because it is tightly fitted to the axial inner cavity 132 a. Thereby, the cooling oil within the axial lumen 132a will be blocked by the electrical conductor 133. Correspondingly, when the motor 13 is an oil-cooled motor, the one end 135a of the conductive post includes an oil baffle 135a1, and the size of the oil baffle 135a1 along the radial direction of the motor shaft 132 is not smaller than the inner diameter of the axial inner cavity 132 a. Thereby, the cooling oil in the casing 131 will be blocked by the oil baffle 135a 1. By providing the oil deflector 135a1 and the electric conductor 133, a partial sealed space can be formed in the axial inner chamber 135a, which is surrounded by the electric conductor 133, the oil deflector 135a1, and a partial inner wall of the axial inner chamber 132 a. The conductive brush 134 is located inside the sealed space, thereby ensuring that the conductive brush 134 works in an oil-free environment and ensuring reliable conduction between the conductive brush 134 and the conductive body 13.

With continued reference to fig. 4-7, the oil baffle 135a1 is disposed coaxially with the motor shaft 132. The arrangement is beneficial to processing and assembly.

Referring to fig. 6, the middle portion of the oil baffle 135a1 further includes a through hole, and the conductive structure further includes a connection member 137, and the connection member 137 is connected to the first portion 135b1 through the through hole, thereby fixing the oil baffle 135a1 to the first portion 135b1. By way of example, the connection 137 may be a rivet or screw, or the like. Of course, in practical applications, the oil baffle 135a1 and the first portion 135b1 may be configured as an integral structure, which is not limited in the present application. It should be noted that, compared to the oil baffle 135a1 and the first portion 135b1 being provided as a single structure, the oil baffle 135a1 and the first portion 135b1 being provided as separate structures are more beneficial to the replacement and maintenance of subsequent components and lower process cost.

With continued reference to fig. 4-7, the conductive post has an end 135a that further includes a connecting arm 135a2, and the connecting arm 135a2 extends radially along the motor shaft 132 and is radially and divergently distributed. At least two of the connection arms 135a2 are provided, and three of the connection arms 135a2 are exemplified. The angles of adjacent connections 1392 may be approximately equal. One end of the connection arm 135a2 is connected to the casing 131, and the other end of the connection arm 135a2 is connected to the oil baffle 135a 1. By the arrangement, the connection strength between one end 135a of the conductive column and the casing 131 is improved, and the stability and reliability of the conductive structure are improved. In addition, the connecting arm 135a2 is reliable in structure and occupies a small space.

Referring to fig. 7, a metal clip 136 is further included between the second portion 135b2 and the conductive brush 134, and by providing the metal clip 136, the clamping force of the second portion 135b2 to the conductive brush 134 can be increased, so as to avoid failure or dispersion of the conductive brush 134 caused by long-time friction with the conductive body 133. In practice, the conductive brush 134 and the metal clip 136 are usually integrated together and sold as a single component for convenience of assembly, and when the conductive brush 134 is made of carbon fiber, the integrated component is called a carbon brush.

With continued reference to fig. 4 and 8 (fig. 8 is a schematic diagram illustrating the cooperation between the platen 142 and the motor 13 in fig. 4), the motor 13 further includes a rotary transformer. Resolver is a sensor for testing the angle between the rotor and stator of motor 13, and includes resolver stator 143 and resolver rotor 144. The annular rotary transformer rotor 144 is sleeved on the motor shaft 132 and rotates along with the motor shaft 132, and in practical application, the rotary transformer rotor 144 is typically pressed by a silicon steel sheet. Further, the annular resolver stator 143 is fixed to the casing 131, and includes an exciting winding, a sine and cosine feedback winding, and the resolver stator 143 is usually concentric with the resolver rotor 144 in practical application, and an inner ring of the resolver stator 143 is spaced from an outer ring of the resolver rotor 144. It should be noted that the resolver is fixed inside the casing 131, and the resolver stator 143, the resolver rotor 144, and the oil baffle 135a1 are all coaxially disposed with the motor shaft 132.

With continued reference to fig. 4 and 8, to better fix the resolver, the motor 13 further includes a pressing plate 14, a pressing plate 142 is located between the connecting arm 135a2 and the casing 131, the pressing plate 14 is clamped with an outer ring of the resolver stator 143, and the fixing member 140 sequentially penetrates through the connecting arm 135a2 and the pressing plate 142 to be finally fixed to the casing 131. This arrangement ensures both stable fixation of resolver stator 143 to housing 131 and reliable conductive connection between connecting arm 135a2 and housing 131.

Further, the diameter of the outer ring of the resolver stator 143 is smaller than or equal to the dimension of the oil baffle 135a1 in the radial direction of the motor shaft 132. By this arrangement, the cooling oil outside the casing 131 can be prevented from being sprayed to the resolver, and thus stable operation of the resolver can be ensured.

Further, the pressing plate 142 is approximately an arc-shaped annular plate structure with a central angle greater than 180 degrees. It should be noted that the platen 142 is configured to be arc-shaped mainly for facilitating the outgoing line of the resolver stator 143. In other words, the resolver stator 143 further includes a wire outlet end (not shown in fig. 4), and the opening of the pressing plate 142 is disposed between the wire outlet end of the resolver stator 143 in the axial direction of the motor shaft 132.

In general, when the motor shaft 132 rotates and generates a shaft voltage, the shaft current may be conducted along the following path: the motor shaft 132, the conductive brush 134, the conductive post 135, the housing 131 and the ground. Therefore, the scheme of the application can release the shaft voltage on the motor shaft to the ground, and the bearing electric corrosion of the rotating shaft bearing 141 is not caused. In addition, the conductive structure of the application has fewer parts, omits the arrangement of the conductive bearing, has simple structure, can realize reliable matching with the axial inner cavity of the motor shaft 132 without complex positioning, and has higher reliability and better conductive performance.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (15)

1. A motor with a motor shaft conductive structure, the motor comprising a housing, a stator, a rotor, a motor shaft and a conductive structure, the housing of the motor being configured to accommodate the stator and the rotor of the motor, the conductive structure being configured to electrically connect the motor shaft and the housing, the conductive structure comprising: the electric conductor is embedded into the axial inner cavity of the motor shaft;

One end of the conductive column is fixedly connected with the shell, and the other end of the conductive column extends into the axial inner cavity;

one end of the conductive brush is fixedly connected with the other end of the conductive column, and the other end of the conductive brush contacts the conductive body;

The hardness of the conductive brush is smaller than that of the conductor.

2. The electric machine of claim 1, wherein the conductive brush has a hardness less than a hardness of the conductive post.

3. The electric machine of claim 1, wherein the electrical conductor comprises a floor recessed toward the conductive brush.

4. A motor as claimed in claim 3, wherein the electrical conductor includes a rim surrounding an edge of the base plate, the rim having an outer diameter not less than an inner diameter of the axial cavity.

5. A motor as claimed in claim 3, wherein the electrical conductor is arranged coaxially with the motor shaft and the electrical conductor brush is arranged coaxially with the motor shaft.

6. The motor of claim 1, wherein one end of the conductive post includes an oil baffle, the oil baffle having a dimension in a radial direction of the motor shaft that is not less than an inner diameter of the axial cavity.

7. The motor of claim 6, wherein one end of the conductive post comprises a connecting arm extending in a radial direction of the motor shaft, one end of the connecting arm is connected to the housing, the other end of the connecting arm is connected to the oil baffle, and the connecting arm is radially divergently distributed.

8. The electric machine according to claim 6, characterized in that the electric machine comprises a resolver stator, the resolver stator being annular, the resolver stator being fixed inside the casing, the resolver stator and the oil baffle being arranged coaxially with the motor shaft, a diameter of an outer ring of the resolver stator being smaller than or equal to a size of the oil baffle in a radial direction of the motor shaft.

9. The motor of claim 7, wherein the motor includes a resolver stator, a pressing plate, and a fixing member, the resolver stator is ring-shaped, the resolver stator is fixed inside the housing, the pressing plate is located between the connection arm and the housing along an axial direction of the motor shaft, the pressing plate is clamped with an outer ring of the resolver stator, and the fixing member is used for fixing the pressing plate and the connection arm to the housing.

10. The motor of claim 1, wherein the other end of the conductive post includes a groove, the groove of the other end of the conductive post being snapped into the conductive brush.

11. The motor of claim 10, wherein a length of the conductive brush is greater than a distance between the other end of the conductive post and the conductive body in an axial direction of the motor shaft.

12. The motor of claim 1, wherein the conductive brush extends in an axial direction of the motor shaft, and a dimension of the conductive brush in a radial direction of the motor shaft is smaller than a dimension of the electrical conductor.

13. The motor of claim 12, wherein a dimension of the other end of the conductive post in a radial direction of the motor shaft is smaller than a dimension of the conductive body.

14. A powertrain comprising a motor of the motor shaft conductive structure of claims 1-13 and a motor controller for controlling operation of the motor shaft conductive structure.

15. An electric vehicle comprising a frame and the powertrain of claim 14, the powertrain mounted to the frame.