Bridge assembly and vehicle
Patent Information
- Application Number
- CN202380080911.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-01-31
- Publication Date
- 2025-07-04
AI Technical Summary
The cooling oil of the oil-cooled motor is insufficient when running at high speed, resulting in high rotor oil churning power loss, and the existing technology is difficult to effectively maintain the fluid level of the motor and gearbox, affecting cooling efficiency and transmission efficiency.
An electric bridge assembly is designed, which connects the motor housing and the gearbox housing through a partition, and sets an overflow hole and an oil return port. The overflow hole is higher than the lowest position of the rotor, and the oil return port is higher than the overflow hole. It is used to maintain the liquid level in the motor cavity and drive the oil back to the motor cavity through the gear, ensuring that the liquid level of the motor and gearbox is appropriate and reducing the loss of oil churning power.
It achieves the maintenance of sufficient cooling oil when the motor is running at high speed, reduces oil churning power loss, ensures efficient cooling and transmission efficiency of the motor and gearbox, and does not require additional electronic control devices, which has a cost advantage.
Smart Images
Figure CN120266378A_ABST
Abstract
Description
Electric bridge assembly and vehicle Technical Field
[0001] The present application relates to the technical field of power devices, and in particular to an electric bridge assembly that can be used in a vehicle and a vehicle including the electric bridge assembly. Background Art
[0002] The electric axle assembly typically consists of a motor and a gearbox. In oil-cooled motors, the rotor is a core component, and adequate cooling ensures the rotor maintains a normal operating temperature. For motors using oil-swing cooling, minimizing rotor churn power losses is crucial.
[0003] In oil-cooled motors, an oil pool forms at the bottom of the motor housing. During motor startup, a large portion of the rotor is submerged in the oil, resulting in significant churning power losses. At high speeds, cooling requirements increase, and the motor can face the problem of insufficient cooling oil.
[0004] Summary of the Invention
[0005] The purpose of the present application is to overcome or at least alleviate the deficiencies of the prior art and to provide an electric bridge assembly and a vehicle including the electric bridge assembly.
[0006] The embodiments of the present application provide an electric bridge assembly, comprising:
[0007] a motor comprising a motor housing, a stator fixed to the motor housing, and a rotor disposed radially inward of the stator;
[0008] a transmission case comprising a transmission case and a plurality of gears housed in the transmission case; and
[0009] a partition plate connected to the motor housing and / or the transmission housing to define a motor cavity on the motor side of the partition plate and a transmission cavity on the transmission side of the partition plate,
[0010] The partition plate is provided with an overflow hole and an oil return port communicating with the motor cavity and the speed change cavity.
[0011] The overflow hole is higher than the lowest position of the rotor and is used to maintain the liquid level in the motor cavity. The height of the oil return port is greater than the height of the overflow hole and is used to return the oil in the speed change cavity to the motor cavity.
[0012] In at least one embodiment, when the electric bridge assembly is not operating, the motor static fluid level in the motor cavity is higher than the transmission static fluid level in the transmission cavity.
[0013] In at least one embodiment, compared to when the electric bridge assembly is not operating, when the electric bridge assembly is operating, the amount of liquid in the motor cavity increases, and the amount of liquid in the transmission cavity decreases.
[0014] In at least one embodiment, when the electric bridge assembly is not operating, the height of the oil in the motor cavity above the rotor is 1 / 5 or less of the radius of the rotor.
[0015] In at least one embodiment, when the electric bridge assembly is working, the oil in the transmission cavity is brought to the vicinity of the oil return port by the rotation of the gear, so that the oil enters the motor cavity through the oil return port.
[0016] In at least one embodiment, the oil return port extends obliquely relative to the axial direction of the electric bridge assembly, and an end portion of the oil return port on the motor side is lower than an end portion on the gearbox side.
[0017] In at least one embodiment, the oil return port is higher than the stator winding end of the stator, and the oil entering the motor cavity from the oil return port falls onto the stator winding end to cool the stator winding.
[0018] In at least one embodiment, the partition is a motor end cover, and the partition includes a radial middle portion and a peripheral portion connected to the radial outside of the radial middle portion, and the peripheral portion is formed to have a U-shaped axial cross-section, the opening of the U-shape faces the speed change chamber, and the oil return port is formed at the connection position of the bottom wall and the side wall of the U-shape.
[0019] In at least one embodiment, the partition plate includes a plurality of reinforcing ribs, and an oil return collection chamber is formed in the partition plate. The chamber is defined by the outer peripheral portion and two adjacent reinforcing ribs and is disposed around the oil return port.
[0020] An embodiment of the present application further provides a vehicle, which includes the electric axle assembly according to the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG1 shows an axial cross-sectional schematic diagram of an electric bridge assembly according to one embodiment of the present application, wherein the oil height in the motor and the gearbox at rest is schematically shown by dashed lines.
[0022] FIG2 shows the electric bridge assembly in FIG1 , wherein the oil height in the motor and the gearbox when the motor is rotating in a steady state is schematically shown by a dotted line.
[0023] FIG3 shows the electric bridge assembly in FIG1 , wherein hollow arrows schematically illustrate the direction of oil flow in the motor and the gearbox when the electric bridge assembly is in operation.
[0024] FIG4 shows a perspective view of a motor of an electric bridge assembly according to one embodiment of the present application.
[0025] FIG5 shows a partially cutaway perspective view of an electric bridge assembly according to one embodiment of the present application. DETAILED DESCRIPTION
[0026] Exemplary embodiments of the present application are described below with reference to the accompanying drawings.
[0027] Embodiments of the present application provide an electric bridge assembly, which can be used for, but is not limited to, a vehicle, such as a pure electric vehicle or a hybrid vehicle.
[0028] The electric bridge assembly can be an oil-cooled electric bridge assembly. The oil can be a lubricating oil, including engine oil. Of course, the specific type or composition of the oil is not limited here, as long as it can provide cooling. Preferably, the oil also has a lubricating effect.
[0029] 1 to 5 , an electric bridge assembly according to one embodiment of the present application may include an electric motor 100 and a gearbox 200 . Electric motor 100 may be an inner rotor electric motor and may include a stator 110 , a rotor 120 , a motor housing 130 , and a rotor shaft 140 . Stator 110 may be fixedly mounted to motor housing 130 , and rotor 120 may be transmission-coupled to rotor shaft 140 to drive rotation of rotor shaft 140 . Rotor 120 and rotor shaft 140 are located radially inward of stator 110 .
[0030] The electric bridge assembly according to this embodiment may further include a partition 300. The motor housing 130 and the partition 300 may be axially fixed together. A motor cavity 190 is defined in the motor housing 130. The stator 110 and the rotor 120 are disposed in the motor cavity 190. The rotor shaft 140 may extend through the partition 300 into the gearbox 200.
[0031] The transmission 200 may include a plurality of gears 210 and a transmission housing 220. The transmission housing 220 and the partition plate 300 are fixedly mounted together to define a transmission chamber 290 in which the gears 210 are accommodated.
[0032] It is understood that the partition 300 is used to separate the motor cavity 190 and the transmission cavity 290. The present application does not limit the specific structure of the partition 300 and its connection method with the motor housing 130 or the transmission housing 220. In one example, the partition 300 can be a motor end cover or a transmission end cover.
[0033] Oil can be stored in both the motor cavity 190 and the transmission cavity 290. It is understood that the oil can be added by the manufacturer, seller, or user of the electric axle assembly. For example, the manufacturer of the electric axle assembly can add oil to the electric axle assembly before it leaves the factory, or the vehicle manufacturer can add oil to the electric axle assembly during vehicle assembly.
[0034] Referring to Figure 1 , a partition plate 300 is provided with an overflow hole 310 and an oil return port 320. Overflow hole 310 may be located at the bottom of partition plate 300, while oil return port 320 is located at the top of partition plate 300. Overflow hole 310 axially connects motor chamber 190 and transmission chamber 290. Overflow hole 310 may extend axially, but is not limited to extending axially.
[0035] In one example, the oil return port 320 may be located near the top of the highest gear 210 in the transmission 200. In one example, a gear in the transmission 200 that performs a shifting function may fling oil to the oil return port 320, or a gear may be specifically provided for the oil return port 320 that is not used for the shifting function of the transmission 200. In one example, an oil slinging structure may be provided on the gear to fling oil in the transmission 200 to the oil return port 320.
[0036] The oil return port 320 axially connects the motor cavity 190 and the transmission cavity 290. The oil return port 320 may extend obliquely relative to the axial direction A of the electric bridge assembly (which coincides with the axial direction of the motor 100), with the motor-side end of the oil return port 320 lower than the transmission-side end. This allows oil near the oil return port 320 to easily flow from the transmission cavity 290 into the motor cavity 190, while preventing it from flowing from the motor cavity 190 into the transmission cavity 290.
[0037] In the expected installation or use posture of the electric bridge assembly, the overflow hole 310 or the lower side of the overflow hole 310 can be slightly higher than the lowest position of the rotor 120. At the same time, the overflow hole 310 can be higher than the lowest position of at least some of the gears 210 in the transmission 200. Here, the lowest position of the rotor 120 can be higher than the lowest position of at least some of the gears 210 in the transmission 200.
[0038] 1 , when the electric bridge assembly is not operating (sometimes referred to as static), the motor cavity 190 contains an appropriate oil level. The left dashed line in FIG1 illustrates the motor static oil level 181 in the motor cavity 190. The transmission cavity 290 contains an appropriate oil level. The right dashed line in FIG1 illustrates the transmission static oil level 281 in the transmission cavity 290.
[0039] The motor static fluid level 181 may be higher than the transmission static fluid level 281. Here, the motor static fluid level 181 is determined by the position of the overflow hole 310, or in other words, the motor static fluid level 181 is at the same height as the overflow hole 310.
[0040] In one example, when the electric bridge assembly is not working, the height of the oil in the motor cavity 190 above the rotor 120 can be 1 / 5 or less of the radius of the rotor 120, for example, 1 / 5 to 1 / 10 of the radius of the rotor, so as to reduce the oil stirring power loss and allow enough oil to be carried up to achieve motor cooling.
[0041] The motor static liquid level 181 can be slightly higher than the lowest position of the rotor 120. In this way, when the rotor 120 starts to rotate (that is, the motor starts to rotate or work), the oil in the motor cavity 190 is stirred by the rotor 120, and the oil in the motor cavity 190 is carried to the stator winding end 111 of the stator 110 to cool the winding, and then falls back to the oil pool at the bottom of the motor cavity 190.
[0042] At the same time, the oil in the transmission cavity 290 is brought to a position higher than the motor liquid level by the gear 210 , part of the oil is used for gearbox cooling, and part of the oil enters the motor cavity 190 through the oil return port 320 .
[0043] When the motor 100 rotates in a steady state, the oil in the speed change chamber 290 is rolled up and enters the motor chamber 190 through the oil return port 320. The oil in the motor chamber 190 is rolled up by the rotor 120 and thrown to the stator end and the stator inner hole to cool the motor 100. The motor chamber 190 will obtain more oil, and the excess oil will flow from the overflow hole 310 to the speed change chamber 290.
[0044] The liquid level in the motor 100 is maintained at an appropriate level via the overflow hole 310. The left dashed line in FIG2 illustrates the motor operating liquid level 182 in the motor cavity 190. The motor operating liquid level 182 is determined by the position of the overflow hole 310 and is aligned with the motor static liquid level 181.
[0045] Compared to static state, when the motor 100 rotates, the amount of liquid in the motor cavity 190 increases and the amount of liquid in the transmission cavity 290 decreases. The motor 100 can be fully cooled, and at the same time, the gearbox 200 can also be kept at a high-efficiency working state.
[0046] The dashed line on the right side of FIG2 illustrates the transmission working fluid level 282 in the transmission cavity 290. The transmission working fluid level 282 can be lower than the transmission static fluid level 281. It will be appreciated that the transmission working fluid level 282 can still be higher than the lowest position of at least some of the gears 210 in the transmission 200, thereby spooling up the oil in the oil pool at the bottom of the transmission cavity 290.
[0047] It can be understood that the steady-state rotation of the motor here may refer to the rotation speed of the motor 100 being constant or within a predetermined range.
[0048] It is understandable that when the motor 100 is operating, the rotation and speed changes of the rotor 120 will cause agitation of the oil. The oil that is carried up or thrown up and falls into the motor cavity 190 will also affect the liquid level in the oil pool at the bottom of the motor cavity 190. The liquid level in the motor cavity 190 is not necessarily a stable plane. Similarly, the liquid level in the speed change cavity 290 is not necessarily a stable plane. However, this does not affect the operation and effect of the electric bridge assembly of the present application. The description of the liquid surface or liquid level in the present application is only used to understand the scheme and working principle of the present application, etc., and does not constitute a limitation of the present application.
[0049] Figure 4 shows a partial structure of motor 100 including partition 300. Referring to Figures 2 and 5 , on the transmission side, partition 300 may include a plurality of reinforcing ribs 330 extending along radial direction R. In the circumferential direction C of the motor, oil return port 320 may be located between two adjacent reinforcing ribs 330.
[0050] The radial middle portion 340 of the partition 300 may protrude toward the transmission side, thereby forming an annular recess on the motor side that can accommodate the stator winding end 111. The stator winding end 111 may protrude further than the stator core toward both axial sides of the motor.
[0051] The partition plate 300 may include an inner peripheral portion 350 connected to the radially inner side of the radial middle portion 340, and an outer peripheral portion 360 connected to the radially outer side of the radial middle portion 340. The outer peripheral portion 360 may be located on the motor side of the radial middle portion 340 and may have a U-shaped axial cross-section, with the opening of the U facing the transmission chamber 290. The oil return port 320 may be formed at the junction of the bottom wall and the lower side wall of the U-shape. As shown in FIG5 , the oil return port 320 may be slightly higher than the stator winding end 111. Oil entering the motor chamber 190 through the oil return port 320 may fall onto the stator winding end 111 to cool the stator winding.
[0052] An oil return collection chamber 370 defined by an outer peripheral portion 360 and two adjacent reinforcing ribs 330 and arranged around the oil return port 320 can be formed in the partition 300. Even if the oil reaching the oil return collection chamber 370 does not directly reach the oil return port 320, it is easy to accumulate in the oil return collection chamber 370 and enter the motor cavity 190 through the oil return port 320.
[0053] It is understood that the number of oil return ports 320 is not limited to one, and two or more oil return ports 320 may be provided. The oil return port 320 may be a circular oil return hole, or the cross section of the oil return port 320 may be formed into a square or elongated shape.
[0054] It is understood that the number of overflow holes 310 is not limited to one, and two or more overflow holes 310 may be provided. The overflow hole 310 may be provided in the radial middle portion 340 to control the liquid level in the motor cavity 190 .
[0055] The electric bridge assembly of the present application can achieve separate control of the liquid levels in the motor cavity 190 and the transmission cavity 290, ensuring that both are at ideal liquid levels, thereby improving the transmission efficiency of the electric bridge assembly. The electric bridge assembly of the present application eliminates the need for additional electronic control devices for liquid level control, thus offering cost advantages.
[0056] It will be appreciated that in other possible embodiments, the electric bridge assembly may include, for example, an oil supply structure or mechanism disposed in the transmission cavity 290 for supplying oil in the transmission cavity 290 to the oil return port 320. In one example, the oil supply structure or mechanism may include an oil guide structure that may cooperate with gears, etc. In another example, the oil supply structure or mechanism may include one or more of an oil pump, an oil guide structure, and an oil supply pipeline or channel.
[0057] The oil control mechanism of the electric bridge assembly of the present application has a simple structure and high reliability. It can ensure that the motor cavity 190 is at an ideal oil level in any state (including when the motor starts to rotate and when it is in steady state rotation), ensuring cooling effect without causing high oil stirring power loss.
[0058] An embodiment of the present application further provides a vehicle, which includes the electric bridge assembly according to the present application. The vehicle may be a pure electric vehicle or a hybrid vehicle.
[0059] It can be understood that the partition 300 of the embodiment of the present application can be sold as a separate accessory and can also be a protected subject of the present application.
[0060] It should be understood that at least some aspects or features of the above-mentioned embodiments, examples or examples may be appropriately combined.
[0061] It is understood that in this application, when the number of parts or components is not specifically limited, the number may be one or more, and the term "plurality" herein refers to two or more. Where the number of parts or components is shown in the drawings and / or described in the specification as a specific number, such as two, three, or four, the specific number is generally illustrative and not restrictive, and may be understood as a plurality, i.e., two or more. However, this does not mean that this application excludes the case of one.
[0062] The present application is not limited to the above-mentioned embodiments, examples or examples. Those skilled in the art may make various modifications to the above-mentioned embodiments, examples or examples of the present application under the guidance of the present application without departing from the scope of the present application.
[0063] Industrial applicability
[0064] The electric bridge assembly provided by the embodiments of the present application can be, but is not limited to, used in vehicles.
[0065] Reference Signs List
[0066] 100 motors
[0067] 110 stator
[0068] 111 Stator winding ends
[0069] 120 rotor
[0070] 130 motor housing
[0071] 140 rotor shaft
[0072] 181 Motor static level
[0073] 182 Motor working fluid level
[0074] 190 motor cavity
[0075] 200 gearbox
[0076] 210 Gear
[0077] 220 gearbox housing
[0078] 281 Transmission static fluid level
[0079] 282 Transmission operating fluid level
[0080] 290 speed change chamber
[0081] 300 partition
[0082] 310 overflow hole
[0083] 320 oil return port
[0084] 330 reinforcement
[0085] 340 radial middle part
[0086] 350 inner periphery
[0087] 360 Peripheral part
[0088] 370 Return oil collection chamber
[0089] A Axial
[0090] R Radial
[0091] C Circumferential
Claims
1. A bridge assembly comprising: A motor (100) comprising a motor housing (130), a stator (110) fixed to the motor housing (130), and a rotor (120) disposed radially inward of the stator (110); A gearbox (200) comprising a gearbox housing (220) and a plurality of gears (210) housed in the gearbox housing (220); as well as a partition (300) connected to the motor housing (130) and / or the gearbox housing (220) to define a motor cavity (190) on the motor side of the partition (300) and a gearbox cavity (290) on the gearbox side of the partition (300), The partition plate (300) is formed with an overflow hole (310) and an oil return port (320) communicating with the motor cavity (190) and the speed change cavity (290). The overflow hole (310) is higher than the lowest position of the rotor (120) and is used to maintain the liquid level in the motor cavity (190). The height of the oil return port (320) is greater than the height of the overflow hole (310) and is used to allow the oil in the speed change cavity (290) to return to the motor cavity (190).
2. The electric bridge assembly according to claim 1, wherein: When the electric bridge assembly is not operating, the motor static fluid level (181) in the motor cavity (190) is higher than the transmission static fluid level (281) in the transmission cavity (290).
3. The electric bridge assembly according to claim 1, wherein: Compared with when the electric bridge assembly is not working, when the electric bridge assembly is working, the amount of liquid in the motor cavity (190) increases, and the amount of liquid in the speed change cavity (290) decreases.
4. The electric bridge assembly according to claim 1, wherein: When the electric bridge assembly is not working, the height of the oil in the motor cavity (190) above the rotor (120) is 1 / 5 or less of the radius of the rotor (120).
5. The electric bridge assembly according to claim 1, wherein: When the electric bridge assembly is working, the oil in the speed change cavity (290) is brought to the vicinity of the oil return port (320) through the rotation of the gear (210), so that the oil enters the motor cavity (190) through the oil return port (320).
6. The electric bridge assembly according to claim 1, wherein: The oil return port (320) extends obliquely relative to the axial direction (A) of the electric bridge assembly, and the motor-side end of the oil return port (320) is lower than the gearbox-side end.
7. The electric bridge assembly according to claim 1, wherein: The oil return port (320) is higher than the stator winding end (111) of the stator (110), and the oil entering the motor cavity (190) from the oil return port (320) falls onto the stator winding end (111) to cool the stator winding.
8. The electric bridge assembly according to claim 1, wherein: The partition (300) is a motor end cover, and includes a radial middle portion (340) and a peripheral portion (360) connected to the radial outer side of the radial middle portion (340). The peripheral portion (360) is formed to have a U-shaped axial cross-section, the opening of the U-shape faces the speed change chamber (290), and the oil return port (320) is formed at the connection position of the bottom wall and the side wall of the U-shape.
9. The electric bridge assembly according to claim 8, wherein: The partition plate (300) includes a plurality of reinforcing ribs (330), and an oil return collection chamber (370) is formed in the partition plate (300), which is defined by the outer peripheral portion (360) and two adjacent reinforcing ribs (330) and is arranged around the oil return port (320).
10. A vehicle comprising the electric bridge assembly according to any one of claims 1 to 9.