Electric drive device, power assembly and vehicle

Abstract

The invention discloses an electric drive device which comprises a first bearing, a conducting ring, a transmission shaft and a shell, the transmission shaft is supported in the shell through the first bearing, and the conducting ring is arranged on the transmission shaft in a sleeving mode and connected between the transmission shaft and the shell; the conducting ring is provided with a first oil channel, the first oil channel is provided with an oil inlet and a first oil outlet, the first oil outlet is located in the side, close to the first bearing, of the conducting ring, and oil flowing out of the first oil outlet can be sprayed to a roller path of the first bearing. According to the electric drive device, electric corrosion protection and lubrication cooling of the first bearing are achieved through a compact structure.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to the field of electric drive technology. Background Art

[0002] In electric drive devices, in order to ensure the cooling and lubrication of the bearings, oil pipes or oil channels are usually required to actively spray oil on the bearings. Since there is shaft current on the motor shaft, conductive brushes are usually required to be installed on the drive shaft to conduct the shaft current to prevent the bearings from being corroded by electricity. The lubrication, cooling and electrical corrosion protection of the bearings require their own related structures, which take up a lot of space, have many parts and are costly. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide an electric drive device that achieves cooling, lubrication and electrical corrosion protection of bearings through a compact structure.

[0004] The present invention provides an electric drive device, comprising a first bearing, a conductive ring, a transmission shaft and a housing, wherein the transmission shaft is supported in the housing through the first bearing, and the conductive ring is sleeved on the transmission shaft and connected between the transmission shaft and the housing; a first oil channel is provided on the conductive ring, the first oil channel having an oil inlet and a first oil outlet, the first oil outlet being located on a side of the conductive ring close to the first bearing, and oil flowing out of the first oil outlet being able to spray onto a raceway of the first bearing.

[0005] The conductive ring and the first bearing of the present invention are both sleeved and connected between the transmission shaft and the housing. A first oil channel is provided on the conductive ring. The oil entering the first oil channel from the oil inlet is sprayed from the first oil outlet to the raceway of the first bearing to lubricate and cool the first bearing. The shaft current on the transmission shaft flows to the housing through the conductive ring with lower resistivity, thereby preventing the shaft current on the transmission shaft from forming a current path between the transmission shaft and the housing through the first bearing and causing electrical corrosion to the first bearing.

[0006] The electric drive device of the present invention realizes electrical corrosion protection and lubrication cooling of the first bearing through a compact structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0008] Figure 1 is a schematic diagram of an electric drive device according to an embodiment of the present invention;

[0009] Figure 2 yes Figure 1 One of the partial enlarged images at point A in the middle;

[0010] Figure 3 yes Figure 1Another enlarged view of the part at A in the middle;

[0011] Figure 4 This is one of the schematic diagrams of the partial structure of the electric drive device according to an embodiment of the present invention;

[0012] Figure 5 This is the second schematic diagram of the partial structure of the electric drive device according to an embodiment of the present invention;

[0013] Figure 6 1 is a schematic diagram of the appearance of a conductive ring according to an embodiment of the present invention;

[0014] Figure 7 is a schematic front view of a conductive ring according to an embodiment of the present invention;

[0015] Figure 8 is a schematic side cross-sectional view of a conductive ring according to an embodiment of the present invention;

[0016] Figure 9 is a schematic front view of a first conductive brush according to an embodiment of the present invention;

[0017] Figure 10 1 is a schematic side cross-sectional view of a first conductive brush according to an embodiment of the present invention.

[0018] Reference numerals:

[0019] 100-conductive ring, 110-conductive ring body, 111-first sealing part, 1111-first sealing body, 1112-first sealing lip, 112-second sealing part, 1121-second sealing body, 1122-second sealing lip, 113-third sealing part, 1131-third sealing body, 1132-third sealing lip, 114-first oil channel, 1141-oil inlet, 1142-first oil outlet, 1143-second oil outlet, 120-first conductive brush, 121-conductive brush base, 122-conductive brush bristles, 123-elastic pin, 130-second conductive brush, S1-first sealed space, S2-second sealed space,

[0020] 200-housing, 210-second oil passage,

[0021] 300-drive shaft, 310-motor shaft, 320-transmission shaft,

[0022] 400-first bearing,

[0023] 500-Second bearing. DETAILED DESCRIPTION

[0024] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] In the description of the present invention, "first feature" or "second feature" may include one or more of the features.

[0027] In the description of the present invention, “a plurality of” means two or more, and “a number of” means one or more.

[0028] Bearing life directly impacts the life of the electric drive unit. Numerous factors influence bearing life, with poor lubrication and cooling and electrical corrosion being two key factors. In some applications, gear oil stirring is used to splash lubricate the bearings. However, this method of lubrication may not meet the lubrication and cooling needs of the bearings due to insufficient lubricant volume and / or lubrication locations. In such cases, active oil spray lubrication becomes a preferred option. Some related technologies install lubricating oil pipes at locations within the electric drive unit where lubrication is required. Lubricating oil is pumped through the pipes to spray lubricate at the required flow rate. Other related technologies install lubricating oil channels and oil spray ports on the bearing mounting seat of the housing 200 to lubricate and cool the bearings. Regarding electrical corrosion protection for bearings, the mainstream solution currently used on the market is to install a conductive ring 100 between the drive shaft 300 and the housing 200.

[0029] However, when a conductive ring 100 is provided next to the bearing of the housing 200 to protect the bearing from damage by shaft current, and a lubricating oil channel is provided to lubricate and cool the bearing, on the one hand, the structural integration of the electric drive device is low, and on the other hand, additional lubricating oil pipes need to be added or the processing difficulty of the housing 200 is increased, which is costly.

[0030] The present invention proposes an electric drive device, including a first bearing 400, a conductive ring 100, a transmission shaft 300 and a housing 200. The transmission shaft 300 is supported in the housing 200 through the first bearing 400. The conductive ring 100 is sleeved on the transmission shaft 300 and connected between the transmission shaft 300 and the housing 200. A first oil channel 114 is provided on the conductive ring 100. The first oil channel 114 has an oil inlet 1141 and a first oil outlet 1142. The first oil outlet 1142 is located on a side of the conductive ring 100 close to the first bearing 400. The oil flowing out of the first oil outlet 1142 can be sprayed onto the raceway of the first bearing 400.

[0031] like Figures 1 to 3 In some embodiments of the present invention, the conductive ring 100 and the first bearing 400 are both sleeved and connected between the transmission shaft 300 and the housing 200. A first oil passage 114 is provided on the conductive ring 100. Oil entering the first oil passage 114 from the oil inlet 1141 is sprayed from the first oil outlet 1142 to the raceway of the first bearing 400 to lubricate and cool the first bearing 400. The shaft current on the transmission shaft 300 flows to the housing 200 through the conductive ring 100 having a lower resistivity, thereby preventing the shaft current on the transmission shaft 300 from forming a current path between the transmission shaft 300 and the housing 200 through the first bearing 400 and causing electrical corrosion to the first bearing 400.

[0032] In the aforementioned related art, the first oil passage 114 is disposed on the bearing mount of the housing 200. The bearing mount and the conductive ring 100 each occupy a certain amount of axial space, increasing the length of the drive shaft 300 and the overall dimensions of the electric drive device, hindering the miniaturization and lightweighting of the electric drive device. In the present invention, the conductive ring 100 and the portion of the housing 200 where the first oil passage 114 is disposed share axial space, conserving axial space within the electric drive device. Furthermore, disposing the first oil passage 114 on the conductive ring 100 is less difficult to manufacture, resulting in higher production efficiency and lower costs than disposing the first oil passage 114 on the housing 200.

[0033] Specifically, if Figures 1 to 3The housing 200 is provided with a mounting hole, and the conductive ring 100 is interference-pressed into the mounting hole to achieve good electrical contact with the housing 200, which is also conducive to the conductive ring 100 being firmly installed on the housing 200. The conductive ring 100 is located on one axial side of the first bearing 400. The oil inlet 1141 of the first oil channel 114 is suitable for communicating with the lubricating oil channel of the electric drive device, and the first oil outlet 1142 is opened toward the first bearing 400 so that the oil can be sprayed onto the first bearing 400. The position of the first oil outlet 1142 and the raceway position of the first bearing 400 may or may not be directly opposite. Specifically, the position and oil outlet angle of the first oil outlet 1142 can be adjusted according to the lubrication simulation or test results. As long as the oil sprayed from the first oil outlet 1142 can reach the raceway of the first bearing 400, lubrication and cooling of the first bearing 400 can be achieved. The “facing” mentioned here means that in a plane perpendicular to the axial direction of the transmission shaft 300 , the projection of the first oil outlet 1142 completely falls within the projection of the raceway of the first bearing 400 .

[0034] It is understood that the conductive ring 100 can be made of a good electrical conductor such as metal. The housing 200 is also typically made of a metal such as aluminum alloy or magnesium alloy, which has both good electrical conductivity and good mechanical bearing capacity, providing the necessary support and protection for the components within the electric drive device.

[0035] In some embodiments of the present invention, a second oil channel 210 is provided on the shell 200, the outer peripheral surface of the conductive ring 100 is in contact with the inner wall of the shell 200, the oil inlet 1141 is opened on the outer peripheral surface of the conductive ring 100, and one end opening of the second oil channel 210 is set on the inner wall of the shell 200, and one end opening of the second oil channel 210 is connected to the oil inlet 1141.

[0036] Second oil passage 210 is provided on housing 200. Compared to using an external lubricating oil pipe to supply lubricating oil to the bearing, this increases space utilization within housing 200. The outer circumference of conductive ring 100 is in contact with the inner wall of housing 200, allowing direct connection between second oil passage 210 and first oil passage 114 on housing 200. This eliminates the need for additional components such as oil pipes and connectors, resulting in a simpler and more integrated structure.

[0037] Continue to read Figures 1 to 3 The second oil channel 210 is formed on the housing 200. The housing 200 is provided with a mounting hole for the conductive ring 100. One end opening of the second oil channel 210 is located on the inner wall of the mounting hole. The oil inlet 1141 of the conductive ring 100 is opened on the outer peripheral surface of the conductive ring 100. The conductive ring 100 is installed in the mounting hole so that the oil inlet 1141 of the conductive ring 100 is aligned or partially aligned with the opening of the second oil channel 210, so that the two are connected and the structure of the electric drive device is more integrated.

[0038] As will be appreciated, the electric drive unit has numerous parts requiring lubrication and cooling, and lubrication oil passages are typically provided. Lubricating oil contained within the housing 200 or other container can be pumped out by an oil pump and delivered through the lubrication oil passages to the various parts requiring cooling and lubrication. The second oil passage 210 on the housing 200 communicates with the lubrication oil passages of the electric drive unit.

[0039] In some embodiments of the present invention, the conductive ring 100 includes a conductive ring body 110, a first conductive brush 120 and a first sealing portion 111; the conductive ring body 110 is sleeved on the transmission shaft 300, the first oil channel 114 is provided on the conductive ring body 110, the first oil outlet 1142 is located on the side of the conductive ring body 110 close to the first bearing 400, the first conductive brush 120 and the first sealing portion 111 are both provided between the conductive ring body 110 and the transmission shaft 300, the radial outer side of the first sealing portion 111 is sealed to the conductive ring body 110, the radial inner side of the first sealing portion 111 is sealed to the transmission shaft 300, and the first sealing portion 111 is located on the side of the first conductive brush 120 close to the first bearing 400.

[0040] First, it can be understood that the first oil channel 114 is provided on the conductive ring body 110 , which means that the first oil channel 114 is spaced apart from the first sealing portion 111 to prevent the oil flowing out of the first oil channel 114 from interfering with the sealing of the first sealing portion 111 .

[0041] Because the drive shaft 300 is a rotating component, a deformable, highly conductive brush is an ideal choice for ensuring an effective conductive path between the moving drive shaft 300 and the stationary housing 200. Because the brush is relatively soft, it deforms to fully contact the outer surface of the drive shaft 300. This ensures good electrical contact with the drive shaft 300 even in a bumpy and vibrating operating environment, enhancing the reliability of the electric drive.

[0042] The conductive brush can be of any structure and material in the prior art, and this application does not limit this. In some embodiments, such as Figures 8 to 10As shown, the first conductive brush 120 includes a conductive brush base 121 and conductive bristles 122. The conductive brush base 121 is annular, and the conductive bristles 122 are arranged in multiple groups, equidistantly spaced radially inward from the base 121. The first end of each group of conductive bristles 122 is fixed radially inward from the base 121, while the other end extends radially inward and is free. The radially outer side of the conductive brush base 121 is fixedly connected to the conductive ring body 110. The first conductive brush 120 is sleeved on the transmission shaft 300, and the free end of each group of conductive bristles 122 abuts the outer circumference of the transmission shaft 300. It can be understood that in order to ensure that each group of conductive bristles 122 is in full contact with the transmission shaft 300, the diameter of the circle formed by the radially inner connection structure of the free end of each group of conductive bristles 122 is smaller than the diameter of the contact part between the transmission shaft 300 and the conductive bristles 122. This arrangement can not only ensure that the conductive bristles 122 are in full contact with the outer peripheral surface of the transmission shaft 300 in the initial state, but also ensure that the conductive bristles 122 have a certain wear margin.

[0043] In some embodiments, a mounting groove is provided radially inwardly of the conductive ring body 110. The mounting groove has two sidewalls, and elastic pins 123 are provided axially on either side of the conductive brush base 121. The elastic pins 123 can be compressed or stretched in the axial direction. The conductive brush base 121 can be snapped into the mounting groove on the inner side of the conductive ring body 110, with the elastic pins 123 abutting against the sidewalls of the mounting groove due to compression. To ensure that the conductive brush base 121 is securely mounted on the conductive ring body 110, the conductive brush can have multiple elastic pins 123 to increase the snap-on force.

[0044] In some embodiments, the conductive bristles 122 may be carbon fiber conductive bristles 122 .

[0045] Because lubricating oil typically has a high resistivity and is not easily conductive, the lubricating oil flowing out of the first oil outlet 1142 flows into the gap between the first conductive brush 120 and the transmission shaft 300, affecting their electrical contact and, in turn, the efficiency of current conduction on the transmission shaft 300. To ensure a good conductive path between the first conductive brush 120 and the transmission shaft 300, the first conductive brush 120 needs to be isolated from the lubricating oil, thus requiring a sealing structure.

[0046] Specifically, continue back to Figures 1 to 3 A first sealing portion 111 is provided between the conductive ring body 110 and the transmission shaft 300. The two ends of the first sealing portion 111 are sealed and connected to the outer circumferential surfaces of the conductive ring body 110 and the transmission shaft 300 respectively. The first sealing portion 111 is located between the first conductive brush 120 and the first bearing 400, thereby isolating the lubricating oil flowing out of the first oil channel 114 from the first conductive brush 120, which is conducive to good electrical contact between the first conductive brush 120 and the transmission shaft 300.

[0047] In some embodiments, the first sealing portion 111 and the conductive ring body 110 are integrally formed.

[0048] In some embodiments of the present invention, the electric drive device includes a first bearing 400 and a second bearing 500, the transmission shaft 300 is supported in the housing 200 through the first bearing 400 and the second bearing 500, and the conductive ring 100 is located between the first bearing 400 and the second bearing 500; the first oil channel 114 also has a second oil outlet 1143, the second oil outlet 1143 is located on the side of the conductive ring body 110 close to the second bearing 500, and the oil flowing out of the second oil outlet 1143 can be sprayed onto the raceway of the second bearing 500.

[0049] like Figures 1 to 3 As shown, lubricating oil from the first oil passage 114 of the conductive ring 100 is ejected from the first oil outlet 1142 to the raceway of the first bearing 400, lubricating and cooling the first bearing 400. Oil ejected from the second oil outlet 1143 to the raceway of the second bearing 500 lubricates the second bearing 500. Using a single conductive ring 100 to lubricate and cool both bearings makes the electric drive device more compact.

[0050] Since the oil sprayed out from the second oil outlet 1143 will also flow between the first conductive brush 120 and the transmission shaft 300 and affect the electrical contact between the two, in some embodiments of the present invention, the conductive ring 100 also includes a second sealing portion 112, which is arranged between the conductive ring body 110 and the transmission shaft 300, and the radial outer side of the second sealing portion 112 is sealed to the conductive ring body 110, and the radial inner side of the second sealing portion 112 is sealed to the transmission shaft 300, and the second sealing portion 112 is located on the side of the first conductive brush 120 close to the second bearing 500.

[0051] The specific configuration of the second sealing portion 112 may be the same as or different from that of the first sealing portion 111 , and may be configured according to actual needs, which will not be described in detail here.

[0052] Please continue reading Figures 1 to 3 The first sealing part 111, the second sealing part 112, the radial inner side of the conductive ring body 110 and the outer peripheral surface of the transmission shaft 300 form a first sealed space S1. The first conductive brush 120 is located in the first sealed space S1, which completely avoids the influence of the lubricating oil and improves the conductive ring 100's effect of extracting the shaft current on the transmission shaft 300.

[0053] Furthermore, in some embodiments of the present invention, Figures 1 to 3The first sealing portion 111 includes a first sealing body 1111 and a first sealing lip 1112, the first sealing body 1111 is connected between the conductive ring body 110 and the first sealing lip 1112, the radial outer side of the first sealing lip 1112 is sealed with the first sealing body 1111, and the radial inner side of the first sealing lip 1112 is elastically connected to the outer peripheral surface of the transmission shaft 300 to form a sealing structure therebetween; and / or, the second sealing portion 112 includes a second sealing body 1121 and a second sealing lip 1122, the second sealing body 1121 is connected between the conductive ring body 110 and the second sealing lip 1122, the radial outer side of the second sealing lip 1122 is sealed with the second sealing body 1121, and the radial inner side of the second sealing lip 1122 is elastically connected to the outer peripheral surface of the transmission shaft 300 to form a sealing structure therebetween.

[0054] For details, please refer to Figure 3 The first sealing portion 111 forms a sealing structure by sealingly connecting the first sealing lip 1112 on its radially inner side with the outer circumference of the transmission shaft 300. The second sealing portion 112 forms a sealing structure by sealingly connecting the second sealing lip 1122 on its radially inner side with the outer circumference of the transmission shaft 300. This facilitates the first sealing portion 111 and the second sealing portion 112 to form a rotating sealing structure with the transmission shaft 300. The sealing structure between the first sealing lip 1112, the first sealing body 1111, and the transmission shaft 300 can refer to the sealing structure of a rotary oil seal in the prior art in combination with actual use, and this application does not limit this. Similarly, the sealing structure between the second sealing lip 1122, the second sealing body 1121, and the transmission shaft 300 can refer to the sealing structure of a rotary oil seal in the prior art in combination with actual use.

[0055] In some embodiments of the present invention, the transmission shaft 300 includes a motor shaft 310 and a transmission shaft 320, the motor shaft 310 and the transmission shaft 320 are coaxially connected, the conductive ring 100 is located on the motor shaft 310 or the transmission, one of the first bearing 400 and the second bearing 500 is located on the motor shaft 310, and the other of the first bearing 400 and the second bearing 500 is located on the transmission shaft 320.

[0056] Specifically, if Figure 1The conductive ring 100 is sleeved on the motor shaft 310. The first bearing 400 is connected between the motor shaft 310 and the housing 200. The second bearing 500 is connected between the transmission shaft 320 and the housing 200. The conductive ring 100 is located between the first bearing 400 and the second bearing 500. With this arrangement, lubricating oil from the first oil passage 114 of the conductive ring 100 is ejected from the first oil outlet 1142 onto the raceway of the first bearing 400, lubricating and cooling the first bearing 400, i.e., the motor shaft 310 bearing. Oil ejected from the second oil outlet 1143 onto the raceway of the second bearing 500 lubricates the second bearing 500, i.e., the transmission shaft 320 bearing. Using a single conductive ring 100 to simultaneously lubricate and cool both the motor shaft 310 bearing and the transmission shaft 320 bearing increases the reliability of the motor and transmission, and also makes the electric drive device more compact.

[0057] Since the shaft current is generated on the motor shaft 310, the conductive ring 100 is mounted on the motor shaft 310 to divert the shaft current away from the source, maximally protecting the bearings within the electric drive device from electrical corrosion. Furthermore, the conductive ring 100 is also electrically connected between the transmission shaft 320, which is coaxially connected to the motor shaft 310, and the housing 200. The transmission input shaft, typically coaxially connected to the motor shaft 310, is also the source of the shaft current. By diverting the shaft current from the transmission input shaft through the conductive ring 100, the anti-electrocorrosion protection of the bearings within the transmission can be further enhanced.

[0058] In some embodiments of the present invention, the electric drive device can also be configured as a power generation device, also known as a range extender. In this embodiment, the transmission output shaft is directly connected to the motor shaft 310. It is understandable that the transmission receives power from other power sources such as the engine, and after reducing the torque and increasing the speed, it transmits the power to the motor through the transmission output shaft to drive the motor to generate electricity. In this case, the motor is a generator, and the electric drive device is also called a range extender. The shaft current generated on the motor shaft 310 can also be extracted through the conductive ring 100.

[0059] In some embodiments of the present invention, the conductive ring 100 and the first bearing 400 are located on the motor shaft 310 , the second bearing 500 is located on the transmission shaft 320 , and the conductive ring 100 abuts against the end surface of the transmission shaft 320 .

[0060] Conductive ring 100 is sleeved and connected between motor shaft 310 and housing 200, directing the shaft current on motor shaft 310 to housing 200, protecting the bearings on motor shaft 310 from electrical corrosion. Simultaneously, conductive ring 100 abuts the end face of transmission shaft 320, directing the shaft current conducted from motor shaft 310 to transmission shaft 320 to housing 200, protecting the bearings on transmission shaft 320 from electrical corrosion. With this arrangement, the electric drive device directs shaft current through two conductive paths via conductive ring 100, increasing the speed of current delivery and enhancing the electrical corrosion protection of the bearings.

[0061] like Figure 5 In the illustrated embodiment, the conductive ring 100 is in electrical contact with the motor shaft 310 via a first conductive brush 120. The conductive ring 100 also includes a second conductive brush 130. One end of the second conductive brush 130 is fixed to the conductive ring body 110, and the other end of the second conductive brush 130 abuts the end surface of the transmission shaft 320. In other words, the conductive ring 100 is also in electrical contact with the transmission shaft 320 via the second conductive brush 130. In this embodiment, the electric drive device has two shaft current extraction paths, which improves shaft current extraction efficiency.

[0062] Shaft current path 1: motor shaft 310 → first conductive brush 120 → conductive ring body 110 → housing 200

[0063] Shaft current path 2: transmission shaft 320 → second conductive brush 130 → conductive ring body 110 → housing 200 In some embodiments of the present invention, the conductive ring 100 and the first bearing 400 are located on the motor shaft 310, the second bearing 500 is located on the transmission shaft 320, and the conductive ring 100 abuts against the end face of the inner ring of the second bearing 500.

[0064] The conductive ring 100 is sleeved and connected between the motor shaft 310 and the housing 200. This allows the shaft current on the motor shaft 310 to be directed to the housing 200, protecting the bearing on the motor shaft 310 from electrical corrosion. Simultaneously, the conductive ring 100 abuts the end face of the inner ring of the second bearing 500, allowing the shaft current conducted from the motor shaft 310 to the transmission shaft 320 to be directed to the housing 200 through the inner ring of the second bearing 500, protecting the bearing on the transmission shaft 320 from electrical corrosion. With this arrangement, the electric drive device directs the shaft current through two conductive paths via the conductive ring 100, increasing the speed of shaft current conduction and enhancing the electrical corrosion protection of the bearings.

[0065] like Figure 4In the illustrated embodiment, the conductive ring 100 is in electrical contact with the motor shaft 310 via a first conductive brush 120. The conductive ring 100 also includes a second conductive brush 130, one end of which is fixed to the conductive ring body 110. The other end of the second conductive brush 130 abuts the end surface of the inner ring of the second bearing 500. In other words, the conductive ring 100 is also in indirect electrical contact with the transmission shaft 320 via the second conductive brush 130. In this embodiment, the electric drive device has two shaft current extraction paths, both of which provide equally effective shaft current extraction.

[0066] Shaft current path 1: motor shaft 310 → first conductive brush 120 → conductive ring body 110 → housing 200

[0067] Shaft current path 2: transmission shaft 320 → inner ring of second bearing 500 → second conductive brush 130 → conductive ring body 110 → housing 200

[0068] Furthermore, since the electrical contact between the second conductive brush 130 and the inner ring of the transmission shaft 320 or the second bearing 500 will also be affected by the lubricating oil, some embodiments of the present invention also isolate the second conductive brush 130 from the lubricating oil to ensure that the conductive ring 100 can conduct the shaft current on the transmission shaft 320 through the second conductive brush 130.

[0069] In some embodiments of the present invention, Figures 1 to 3 The conductive ring body 110 includes a second conductive brush 130, one end of which is fixed on the conductive ring body 110, and the other end of the second conductive brush 130 abuts against the transmission shaft 320 or the end face of the inner ring of the transmission shaft 320 bearing; the conductive ring body 110 also includes a third sealing portion 113, which extends from the axial side of the conductive ring body 110 to the inner ring end face of the transmission shaft 320 bearing; the second sealing portion 112, the third sealing portion 113, the inner ring end face of the transmission shaft 320 bearing, the end face of the transmission shaft 320 and the outer peripheral surface of the first shaft enclose a second sealed space S2, and the second conductive brush 130 is located in the second sealed space S2.

[0070] In some embodiments, the third sealing portion 113 may also include a third sealing body 1131 and a third sealing lip 1132. Figure 3 As shown, the third sealing body 1131 is connected between the conductive ring body 110 and the third sealing lip 1132, one end of the third sealing lip 1132 is sealedly connected to the third sealing body 1131, and the other end of the third sealing lip 1132 is elastically connected to the end face of the inner ring of the second bearing 500 to form a sealing structure between the two.

[0071] It should be noted that when the transmission shaft 320 and the motor shaft 310 and the connection between the two are part of the second sealed space S2, the transmission shaft 320 and the motor shaft 310 also need to be sealed, that is, a seal (not shown in the figure) needs to be provided between the transmission shaft 320 and the motor shaft 310. Specifically, a sealing groove can be provided on the motor shaft 310, and a sealing ring or oil seal is provided in the sealing groove to form a sealed connection between the motor shaft 310 and the transmission shaft 320, so as to ensure that the second sealed space S2 can reliably isolate the second conductive brush 130 from the lubricating oil.

[0072] In some embodiments of the present invention, the motor shaft 310 and the transmission shaft 320 of the electric drive device are at least partially sleeved with each other.

[0073] like Figure 1 The transmission shaft 320 includes a hollow section that is sleeved onto the motor shaft 310. The transmission shaft 320 is mounted radially outward of the hollow section. The term "hollow" here refers to a hollow structure within the transmission shaft 320. Specifically, material is removed axially from the end face of the transmission shaft 320 near the motor shaft 310 to create a semi-enclosed space within the transmission shaft 320, or an open space extending through both ends of the transmission shaft 320. It is understood that the inner wall of this space is cylindrical, with the axis of the transmission shaft 320 as its centerline.

[0074] The transmission shaft 320 and the motor shaft 310 are arranged in a sleeve-type arrangement through a hollow section. Firstly, it is convenient to set up a power transmission structure between the motor shaft 310 and the transmission shaft 320. Compared with the power transmission between two non-sleeved shafts through a coupling, the transmission shaft 320 is sleeved on the outside of the motor shaft 310. The transmission shaft 320 and the motor shaft 310 can be keyed, which has a simple structure, convenient processing, and low cost. Specifically, a keyway can be provided on the transmission shaft 320, and a key can be provided on the motor shaft 310. Of course, the key connection here can be a flat key connection, a spline connection, or other forms of key connection.

[0075] The transmission shaft 320 and the motor shaft 310 are connected through a hollow section. Secondly, compared with the coupling connection, the connection structure is more compact. More importantly, it shortens the distance from the end face of the transmission shaft 320 to the conductive ring 100 sleeved on the end of the motor shaft 310 close to the transmission shaft 320, so as to facilitate the setting of the conductive structure between the end face of the transmission shaft 320 or the bearing end face of the transmission shaft 320 and the conductive ring body 110.

[0076] In recent years, in order to increase the power density of motors, the speed of motors has become increasingly higher. For high-speed rotating bearings, the lubricating oil will inevitably be affected by airflow impact, atomization, centrifugation, etc. before reaching the rolling elements in the raceway. That is, there is a "wind barrier", which greatly reduces the amount of effective lubricating oil entering the bearing raceway.

[0077] In some embodiments of the present invention, in the radial direction of the transmission shaft 300 , the distance from the first oil outlet 1142 to the inner ring of the first bearing 400 is smaller than the distance from the first oil outlet 1142 to the outer ring of the first bearing 400 .

[0078] Specifically, if Figure 3 In the radial direction of the transmission shaft 300, the distance from the first oil outlet 1142 to the inner side of the outer ring of the first bearing 400 is L1, and the distance from the first oil outlet 1142 to the outer side of the inner ring of the first bearing 400 is L2, with L1 > L2. In other words, in the radial direction of the transmission shaft 300, the first oil outlet 1142 is positioned closer to the inner ring of the first bearing 400. This allows the oil entering the raceway of the first bearing 400 from the first oil outlet 1142 to pass through the raceway of the first bearing 400 for a longer period of time and in greater quantities, reducing the centrifugal force that causes the lubricating oil to splash, thereby more fully and effectively lubricating and cooling the first bearing 400. Consequently, this dimensional relationship enhances the lubrication of the first bearing 400 and increases the lifespan of both the first bearing 400 and the electric drive device.

[0079] In some embodiments of the present invention, the distance from the second oil outlet 1143 to the inner ring of the second bearing 500 is smaller than the distance from the second oil outlet 1143 to the outer ring of the second bearing 500 .

[0080] Specifically, if Figure 3 In the radial direction of the transmission shaft 300, the distance from the second oil outlet 1143 to the inner side of the outer ring of the second bearing 500 is L3, and the distance from the second oil outlet 1143 to the outer side of the inner ring of the second bearing 500 is L4, where L3>L4. In other words, in the radial direction of the transmission shaft 300, the second oil outlet 1143 is positioned closer to the inner ring of the second bearing 500. This allows the oil entering the raceway of the second bearing 500 from the second oil outlet 1143 to pass through the raceway of the second bearing 500 for a longer time and in greater quantities, reducing the centrifugal force that causes the lubricating oil to splash, thereby more fully and effectively lubricating and cooling the second bearing 500. Therefore, this dimensional relationship enhances the lubrication effect of the second bearing 500 and increases the lifespan of the second bearing 500 and the electric drive device.

[0081] In the embodiments of the present invention, the electric drive device can be configured to satisfy the first relationship L1>L2, or the second relationship L3>L4. Alternatively, the electric drive device can be configured to satisfy both the first relationship L1>L2 and the second relationship L3>L4. The specific conditions can be comprehensively considered based on the actual conditions such as the motor speed and transmission ratio in the electric drive device.

[0082] In some embodiments of the present invention, Figures 6 to 8 The conductive ring 100 is configured with axially symmetrical structures, facilitating its manufacture and eliminating error-proofing requirements during assembly, thereby improving the production efficiency of the electric drive device. Specifically, the conductive ring body 110 is provided with second conductive brushes 130 and corresponding sealing structures on both axial sides. During assembly, the conductive ring 100 does not need to be specifically aligned with the side of the conductive ring 100 with the second conductive brushes 130 facing the second bearing 500, thereby improving production cycle time.

[0083] An embodiment of the present invention further provides a powertrain, including the above-mentioned electric drive device. The powertrain provided by the present invention has all the beneficial effects of the above-mentioned transmission. The powertrain can be a pure electric powertrain, a hybrid powertrain, or of course a fuel powertrain.

[0084] An embodiment of the present invention further provides a vehicle, comprising the above-mentioned electric drive device or the above-mentioned power assembly. The vehicle provided by the present invention has all the beneficial effects of the above-mentioned electric drive device or power assembly.

[0085] In this specification, reference to terms such as "specific embodiment" and "specific example" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example.

[0086] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. An electric drive device, characterized in that: It comprises a first bearing, a conductive ring, a transmission shaft and a housing, wherein the transmission shaft is supported in the housing through the first bearing, and the conductive ring is sleeved on the transmission shaft and connected between the transmission shaft and the housing; The conductive ring is provided with a first oil channel having an oil inlet and a first oil outlet. The first oil outlet is located on a side of the conductive ring close to the first bearing. The oil flowing out of the first oil outlet can be sprayed onto the raceway of the first bearing.

2. The electric drive device according to claim 1, characterized in that: A second oil channel is provided on the shell, the outer circumferential surface of the conductive ring is in contact with the inner wall of the shell, the oil inlet is opened on the outer circumferential surface of the conductive ring, one end opening of the second oil channel is provided on the inner wall of the shell, and the one end opening of the second oil channel is connected to the oil inlet.

3. The electric drive device according to claim 1, characterized in that: The conductive ring comprises a conductive ring body, a first conductive brush and a first sealing portion; The conductive ring body is sleeved on the transmission shaft, the first oil channel is arranged on the conductive ring body, the first oil outlet is located on a side of the conductive ring body close to the first bearing, the first conductive brush and the first sealing portion are both arranged between the conductive ring body and the transmission shaft, the radial outer side of the first sealing portion is sealed to the conductive ring body, the radial inner side of the first sealing portion is sealed to the transmission shaft, and the first sealing portion is located on a side of the first conductive brush close to the first bearing.

4. The electric drive device according to claim 3, characterized in that: Also includes a second bearing, the transmission shaft is supported in the housing through the second bearing, and the conductive ring is located between the first bearing and the second bearing; The first oil channel also has a second oil outlet, and the second oil outlet is located on a side of the conductive ring body close to the second bearing. The oil flowing out of the second oil outlet can be sprayed onto the raceway of the second bearing.

5. The electric drive device according to claim 4, characterized in that: The conductive ring also includes a second sealing portion, which is arranged between the conductive ring body and the transmission shaft, the radial outer side of the second sealing portion is sealed to the conductive ring body, the radial inner side of the second sealing portion is sealed to the transmission shaft, and the second sealing portion is located on the side of the first conductive brush close to the second bearing.

6. The electric drive device according to claim 4, characterized in that: The transmission shaft includes a motor shaft and a transmission shaft, the motor shaft and the transmission shaft are coaxially connected, the conductive ring is located on the motor shaft or the transmission, one of the first bearing and the second bearing is located on the motor shaft, and the other of the first bearing and the second bearing is located on the transmission shaft.

7. The electric drive device according to claim 6, characterized in that: The conductive ring and the first bearing are located on the motor shaft, the second bearing is located on the transmission shaft, and the conductive ring abuts against an end surface of the transmission shaft.

8. The electric drive device according to claim 6, characterized in that: The conductive ring and the first bearing are located on the motor shaft, the second bearing is located on the transmission shaft, and the conductive ring abuts against an end surface of an inner ring of the second bearing.

9. The electric drive device according to claim 7 or 8, characterized in that: The motor shaft and the transmission shaft are at least partially sleeved with each other.

10. The electric drive device according to claim 4 or 5, characterized in that: In the radial direction of the transmission shaft, the distance from the first oil outlet to the inner ring of the first bearing is smaller than the distance from the first oil outlet to the outer ring of the first bearing, and / or; In the radial direction of the transmission shaft, the distance from the second oil outlet to the inner ring of the second bearing is smaller than the distance from the second oil outlet to the outer ring of the second bearing.

11. The electric drive device according to any one of claims 1 to 5, characterized in that: In the radial direction of the transmission shaft, the distance from the first oil outlet to the inner ring of the first bearing is smaller than the distance from the first oil outlet to the outer ring of the first bearing.

12. A power assembly comprising the electric drive device according to any one of claims 1 to 11.

13. A vehicle, comprising the powertrain according to claim 12 or the electric drive device according to any one of claims 1 to 11.

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