A transmission ventilation structure, a transmission and a vehicle

Abstract

The application provides a transmission ventilation structure, a transmission and a vehicle, and relates to the technical field of transmissions.The transmission ventilation structure comprises a main shell, a cover plate and a ventilation plug.The main shell is provided with a speed reducer cavity.The main shell is provided with a ventilation plug hole in communication with the speed reducer cavity.The cavity wall of the speed reducer cavity is provided with a boss.The cover plate is arranged in the speed reducer cavity.The cover plate is matched with the boss to form a labyrinth-shaped fluid cavity.The position of the fluid cavity matches the highest position of the main shell in the installed state.The fluid cavity is arranged in a posture in which liquid in the fluid cavity can naturally flow downward under the action of gravity.The lower end of the fluid cavity is provided with an air inlet.The upper end of the fluid cavity is provided with an air outlet in communication with the ventilation plug hole.The ventilation plug is installed at the end of the ventilation plug hole away from the air outlet.The application can solve the technical problems of the poor isolation effect of the existing ventilation structure and the inflexible arrangement.

Description

Technical Field

[0001] This utility model relates to the field of transmission technology, and in particular to a transmission ventilation structure, a transmission, and a vehicle. Background Technology

[0002] When a transmission is running, internal temperature changes can cause the gas inside the chamber to expand or contract. If the internal pressure is lower than the external environment, a negative pressure is created, making it easy for dust and other foreign objects to be drawn in. Conversely, if the internal pressure is too high, a positive pressure is created, which may cause lubricating oil to leak out. Therefore, a vent plug is usually installed in the transmission to keep the internal air pressure consistent with the ambient air pressure, ensuring reliable operation and long-term sealing of the transmission.

[0003] Currently, a common transmission venting solution involves adding a baffle structure near the vent plug to prevent lubricating oil from spraying directly onto the vent plug and causing leakage. This baffle is typically installed inside the transmission housing and is often integrated with the main transmission housing, using a large flange for assembly. Furthermore, with increasing requirements for vehicle wading performance, some transmissions are beginning to use vent plugs equipped with a polymer breathable membrane. This membrane effectively blocks moisture while allowing airflow, thereby enhancing the transmission's waterproofing capabilities.

[0004] However, while traditional baffle structures can provide some protection against ordinary vent plugs, they have significant shortcomings when applied to polymer breathable membrane vent plugs. Specifically, these shortcomings manifest in the following two aspects: First, the baffle cannot completely prevent the penetration of oil and oil vapor. Under long-term operation, oil or oil vapor can easily wet the breathable membrane, causing its micropores to become clogged or aged, resulting in decreased or even failure of its breathability. Second, existing oil baffle structures are highly dependent on the arrangement of the transmission housing. When limited by vehicle space or specific boundary conditions, they cannot be flexibly adapted to non-housing structures, thus limiting the versatility of the venting solution. Utility Model Content

[0005] This application aims to at least partially solve the technical problems of existing ventilation structures' unsatisfactory oil isolation effect and inflexible layout. To this end, this application proposes a transmission ventilation structure, a transmission, and a vehicle.

[0006] A first aspect of this application provides a transmission ventilation structure, including a main housing and a cover plate. The main housing has a reducer cavity and a vent hole communicating with the reducer cavity. The reducer cavity wall has a boss. The cover plate is disposed inside the reducer cavity and is matched with the boss to form a labyrinthine fluid cavity. The position of the fluid cavity matches the highest point of the main housing in the installed state. The fluid cavity is configured such that the liquid inside can flow naturally downward under the action of gravity. The lower end of the fluid cavity has an air inlet, and the upper end of the fluid cavity has an air outlet communicating with the vent hole. The vent plug is installed at the end of the vent hole away from the air outlet.

[0007] The transmission ventilation structure provided in this application embodiment features a labyrinthine fluid cavity formed by a matching cover plate and a boss within the main housing. This fluid cavity is positioned at the highest point of the main housing, allowing the fluid to flow naturally downwards under gravity. This labyrinthine fluid cavity not only extends the airflow path but also increases the opportunities for oil separation and settling. Furthermore, the rational layout of the inlet and outlet ensures smooth gas flow while preventing lubricating oil or oil vapor from directly impacting the vent plug, reducing the risk of the vent plug becoming wetted, clogged, or aged, and improving the long-term sealing reliability of the transmission. In addition, the independent cover plate and the boss located inside the main housing create a complete ventilation structure within a limited local space. Its form and function are not constrained by the overall layout of the main housing, thus overcoming the dependence of existing oil baffle structures on the arrangement of the transmission housing and enhancing the versatility and adaptability of the ventilation solution in different transmission designs.

[0008] In some embodiments, the main housing has a recessed area near the vent plug mounting position, and the projected area of ​​the fluid cavity along the axial direction of the main housing at least partially intersects the projected area of ​​the recessed area along the axial direction of the main housing.

[0009] In some embodiments, the vent hole is configured such that the liquid inside can flow naturally downwards under gravity.

[0010] In some embodiments, the air inlet is horizontally positioned.

[0011] In some embodiments, the cover plate includes a plate body and a lug provided on the edge of the plate body, the lug covering the boss to form the fluid cavity.

[0012] In some embodiments, the boss and the lug are configured to be flange-face connected.

[0013] In some embodiments, the flange surface of the boss is provided with a plurality of adjacent first recesses, and the flange surface of the lug is provided with second recesses corresponding to the positions of the recesses. Adjacent second recesses are connected, and the air outlet of the second recess located in the exhaust direction is offset from the air inlet of the second recess located in the rear direction. The air inlet and the air outlet are both located on the flange surface of the boss, and the air inlet is connected to the first first recess located in the exhaust direction, and the air outlet is connected to the last first recess located in the exhaust direction.

[0014] In some embodiments, a third recess is provided on the flange surface of the lug, and the third recess corresponds to the position of the air outlet.

[0015] A second aspect of this application provides a transmission, including a rear housing and a transmission ventilation structure of any of the aforementioned structures, wherein the rear housing is used to cover the reducer cavity.

[0016] A third aspect of this application provides a vehicle that uses a transmission with any of the aforementioned structures.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and some of these additional aspects and advantages will become apparent from the description or may be learned by practice of the invention. Attached Figure Description

[0018] Figure 1 This is a first-view structural schematic diagram of the main housing in one embodiment of the present invention; Figure 2 for Figure 1 A magnified view of a section at point A in the middle; Figure 3 This is a schematic diagram of the assembly state of the main shell and the cover plate in one embodiment of the present invention; Figure 4 This is a second-view structural schematic diagram of the main housing in one embodiment of the present invention; Figure 5 for Figure 4 A magnified view of a section at point B in the middle; Figure 6 This is a schematic diagram of the front structure of the cover plate in one embodiment of the present utility model; Figure 7 for Figure 6 A magnified view of a section at point C; Figure 8 This is a schematic diagram of the reverse side of the cover plate in one embodiment of the present utility model; Figure 9 This is a schematic diagram of the transmission structure in one embodiment of the present invention; Explanation of key component symbols: Main housing 100, reducer cavity 110, vent plug hole 120, boss 130, first cavity 131, first rib 132, second rib 133, recessed area 140, air inlet 150, air outlet 160, cover plate 200, plate body 210, lug 220, second cavity 221, third rib 222, fourth rib 223, third cavity 224, vent plug 300, rear housing 400; The following detailed description, in conjunction with the accompanying drawings, will further illustrate this utility model. Detailed Implementation

[0019] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0020] In the description of this utility model, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0021] In the description of this utility model, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features or their sequential relationship.

[0022] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0023] Transmissions typically use vent plugs to maintain internal air pressure consistent with ambient air pressure, ensuring reliable operation and long-term sealing. To prevent lubricating oil from directly spraying onto the vent plug and causing leakage, a baffle structure is usually added inside the transmission housing near the vent plug's mounting location. This baffle structure is often integrated with the main transmission housing, using a large flange for seamless assembly. Furthermore, with increasing demands for vehicle wading performance, some transmissions are beginning to use vent plugs equipped with high-molecular-weight breathable membranes. These membranes effectively prevent moisture ingress while allowing airflow, thus enhancing the transmission's waterproof capabilities.

[0024] However, due to limitations in the baffle structure's ability to isolate oil and oil vapor, long-term operation cannot completely prevent oil or oil vapor from wetting the venting membrane. This easily leads to blockage or aging of the venting membrane's micropores, causing a decrease in the venting performance of the vent plug or even its failure. Furthermore, the oil baffle structure is highly dependent on the arrangement of the transmission's main housing. When constrained by vehicle space or specific boundary conditions, it cannot flexibly adapt to non-main housing structures, limiting the versatility of the venting solution. Under the combined effect of these two factors, the transmission's oil baffle structure ultimately results in an unsatisfactory oil isolation effect, inflexible arrangement, high constraint on layout, and insufficient versatility.

[0025] Therefore, embodiments of this application provide a transmission ventilation structure, a transmission, and a vehicle, which can at least partially solve the technical problems of the existing breather plug's unsatisfactory oil isolation effect and inflexible arrangement.

[0026] This application is described below with reference to the accompanying drawings and specific embodiments: See Figures 1 to 8 In some embodiments, the transmission venting structure includes a main housing 100 and a cover plate 200. Specifically, the right end of the main housing 100 is provided with a reducer cavity 110 for accommodating a reducer assembly, which may include components such as a reduction gear and a differential. The main housing 100 is provided with a vent hole 120 communicating with the reducer cavity 110, and the cavity wall of the reducer cavity 110 is provided with a boss 130. The cover plate 200 is arranged inside the reducer cavity 110, and the cover plate 200 is matched and connected to the boss 130 to form a labyrinthine fluid cavity.

[0027] To ensure that the lubricating oil inside the main housing 100 does not directly wet the fluid cavity in the installed state, the fluid cavity is located near the highest point of the entire main housing 100. At the same time, the lower end of the fluid cavity is provided with an air inlet 150, and the upper end of the fluid cavity is provided with an air outlet 160 communicating with the vent plug hole 120. The vent plug 300 is installed at the end of the vent plug hole 120 away from the air outlet 160.

[0028] To ensure that the oil does not easily flow to the vent plug 300, reduce the risk of oil leakage, and facilitate the return of the oil after the high-temperature oil vapor condenses back into the reducer cavity 110, the direction of the vent plug hole 120 is aligned with the direction of gravity. The fluid cavity is configured such that the liquid inside can flow naturally downward under the action of gravity. For example, the fluid cavity is set vertically, or the fluid cavity is set at an angle but tends to be vertical.

[0029] The transmission ventilation structure provided in the embodiments of this application has the following characteristics: First, the cover plate acts as a physical barrier, effectively preventing the agitated oil from directly entering the fluid cavity; second, even if a small amount of oil enters through the air inlet, the flow path will be greatly extended due to the labyrinth flow channel set in the cavity. During this process, the fluid cavity not only provides sufficient buffer space, but also uses gravity to cause the intruding oil to fall back to the reducer cavity naturally, thereby preventing it from seeping into the vent plug; in addition, when the high-temperature oil and gas flow through this tortuous channel with a large heat dissipation area, it can be fully cooled in a short time, causing the gaseous oil components in it to condense into liquid and flow back to the interior of the reducer cavity along the cavity wall.

[0030] See Figure 4 In some embodiments, the main housing 100 is provided with a recessed region 140 near the installation position of the vent plug 300. The projection area of ​​the fluid cavity along the axial direction of the main housing 100 intersects with the projection area of ​​the recessed region 140 along the axial direction of the main housing 100, or the projection area of ​​the fluid cavity along the axial direction of the main housing 100 is located within the projection area of ​​the recessed region 140 along the axial direction of the main housing 100.

[0031] It should be noted that the space occupied by the recessed area 140 can be set according to the actual situation. For example, the radial dimension of the left side of the main housing 100 near the installation position of the vent plug 300 is smaller than the radial dimension near the installation position of the vent plug 300.

[0032] The transmission ventilation structure provided in this application, through a reasonable arrangement of the axial projection relationship between the recessed area and the fluid cavity, exposes the portion of the main housing near the vent plug mounting position to the air, thereby improving the convective heat transfer efficiency between this portion and the outside air. Furthermore, because the fluid cavity is located near this portion, its cooling performance is enhanced, accelerating the cooling of the high-temperature oil and gas entering the fluid cavity and promoting the liquefaction of the gaseous oil components. Moreover, since the surface of the main housing is typically provided with reinforcing ribs, in this structure, the reinforcing ribs also function as heat dissipation fins, further enhancing the heat dissipation capacity of the fluid cavity.

[0033] If the vent hole 120 is horizontally positioned, oil will accumulate once it enters. Over time, this accumulated oil may solidify or attract impurities, eventually clogging the vent hole 120 and causing the pressure equalization function to fail. Therefore, in some embodiments, the vent hole 120 is configured such that the liquid inside can flow naturally downwards under gravity. For example, the vent hole 120 may be vertically positioned, or inclined, or inclined but tending towards a vertical position. This ensures that any liquid accidentally entering the vent hole 120 can be immediately drained, reducing the risk of clogging and guaranteeing the long-term reliability of the venting function.

[0034] See Figure 2In some embodiments, the air inlet 150 is horizontally positioned.

[0035] The transmission ventilation structure provided in the embodiments of this application connects the horizontally arranged air inlet to the ventilation plug hole, naturally introducing a vertical angle in the oil and gas inflow path. This geometric change can effectively block the oil droplets that surge with the airflow, causing them to separate from the gas under inertia and fall back under gravity, thereby improving the oil and gas separation effect of the fluid cavity.

[0036] See Figure 6 and Figure 8 In some embodiments, the cover plate 200 includes a plate body 210 and a lug 220 disposed on the edge of the plate body 210, the lug 220 covering the boss 130 to form a fluid cavity.

[0037] The transmission ventilation structure provided in the embodiments of this application uses lugs to cover the bosses in the reducer cavity, together forming a labyrinthine fluid cavity. The large area plate that is not covered faces the inside of the reducer cavity, forming an effective oil-blocking structure to prevent the agitated oil from directly entering the fluid cavity.

[0038] See Figure 2 and Figure 7 In some embodiments, the boss 130 and the lug 220 are configured as a flange connection, which can ensure good sealing of the fluid cavity through effective contact over a large area.

[0039] See Figure 2 and Figure 7 In some embodiments, the flange surface of the boss 130 is provided with a plurality of adjacent first recesses 131, and the flange surface of the lug 220 is provided with second recesses 221 corresponding to the positions of the first recesses 131. Adjacent second recesses 221 are connected, and the air outlet end of the second recess 221 located in the exhaust direction is offset from the air inlet end of the second recess 221 located in the exhaust direction. The air inlet 150 and the air outlet 160 are both located on the flange surface of the boss 130, and the air inlet 150 is connected to the first first recess 131 located in the exhaust direction, while the air outlet 160 is connected to the last first recess 131 located in the exhaust direction.

[0040] For example, the flange surface of the boss 130 is provided with three adjacent first recesses 131. The first first recess 131 at the beginning of the exhaust direction is separated from the middle first recess 131 by a first rib 132, and the middle first recess 131 is separated from the last first recess 131 by a second rib 133. Correspondingly, the flange surface of the lug 220 is provided with three adjacent second recesses 221. The exhaust end of the first second recess 221 at the beginning of the exhaust direction is separated from the intake end of the middle second recess 221 by a third rib 222, and the exhaust end of the middle second recess 221 is separated from the intake end of the last second recess 221 by a fourth rib 223. During assembly, the first rib 132 and the third rib 222 are aligned, and the second rib 133 and the fourth rib 223 are aligned, thus forming a labyrinthine fluid cavity.

[0041] The transmission ventilation structure provided in the embodiments of this application provides a series of interconnected but misaligned second concave cavities on the lug flange surface that mates with the boss flange surface. The second concave cavities and the first concave cavities are superimposed to form a three-dimensional labyrinth channel. In this way, the airflow cannot pass through in a straight line and must change direction and speed multiple times in the three-dimensional labyrinth channel. During this process, the gaseous oil components in the high-temperature oil gas cannot keep up with the rapid turning of the airflow due to inertia, and thus continuously impact the ribs and cavity walls. At the same time, after being cooled by the ribs and cavity walls, most of the gaseous oil components in the high-temperature oil gas are effectively stripped from the airflow and flow back into the reducer cavity under the action of gravity.

[0042] See Figure 7 In some embodiments, a third recess 224 is provided on the flange surface of the lug 220, and the third recess 224 corresponds to the position of the air outlet 160. In this way, by partially expanding the volume, a small amount of residual oil that may be carried to this place by the airflow can be effectively collected, and gravity will cause it to flow back along the cavity wall, thereby further reducing the probability of oil entering the vent plug 300 and improving the overall sealing reliability.

[0043] Figure 9 A schematic diagram of the transmission structure provided in an embodiment of this application is shown. See also: Figure 9 The transmission provided in this application includes a rear housing 400 and a transmission ventilation structure of any of the aforementioned structures. During assembly, the rear housing 400 covers the reducer cavity 110.

[0044] The transmission provided in the embodiments of this application, through an independent cover plate and a boss set inside the main housing, can create a complete ventilation functional unit in a limited local space. Its shape and function are not restricted by the overall layout of the main housing, thereby achieving decoupling from the main housing of the transmission. It can flexibly adapt to various platforms and installation boundaries, such as adapting to compact electric drive systems.

[0045] This application also provides a vehicle, which includes a body and a transmission disposed on the body.

[0046] The vehicle provided in the embodiments of this application, by applying the aforementioned transmission, can ensure normal and stable driving of the vehicle.

[0047] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A transmission ventilation structure, characterized in that, include: The main housing has a reducer cavity, and the main housing has a vent hole communicating with the reducer cavity. The cavity wall of the reducer cavity has a boss. A cover plate is disposed inside the reducer cavity. The cover plate is matched and connected to the boss to form a labyrinthine fluid cavity. The position of the fluid cavity matches the highest point of the main housing in the installed state. The fluid cavity is configured such that the liquid inside can flow naturally downward under the action of gravity. The lower end of the fluid cavity is provided with an air inlet, and the upper end of the fluid cavity is provided with an air outlet communicating with the vent plug hole. A vent plug is installed at the end of the vent plug hole that is away from the air outlet.

2. The transmission ventilation structure according to claim 1, characterized in that, The main housing has a recessed area near the vent plug mounting position, and the projection area of ​​the fluid cavity along the axial direction of the main housing at least partially intersects the projection area of ​​the recessed area along the axial direction of the main housing.

3. The transmission ventilation structure according to claim 1, characterized in that, The vent hole is configured such that the liquid inside can flow naturally downwards under the influence of gravity.

4. The transmission ventilation structure according to claim 1, characterized in that, The air inlet is horizontally positioned.

5. The transmission ventilation structure according to claim 1, characterized in that, The cover plate includes a plate body and a lug provided on the edge of the plate body, the lug covering the boss to form the fluid cavity.

6. The transmission ventilation structure according to claim 5, characterized in that, The boss and the lug are configured to be connected by a flange face.

7. The transmission ventilation structure according to claim 6, characterized in that, The flange surface of the boss is provided with a plurality of adjacent first recesses, and the flange surface of the lug is provided with second recesses corresponding to the positions of the recesses. The adjacent second recesses are connected, and the air outlet end of the second recess located in front along the exhaust direction is offset from the air inlet end of the second recess located behind. The air inlet and the air outlet are both located on the flange surface of the boss, and the air inlet is connected to the first cavity at the first position along the exhaust direction, and the air outlet is connected to the first cavity at the last position.

8. The transmission ventilation structure according to claim 7, characterized in that, The flange surface of the lug is provided with a third recess, which corresponds to the position of the air outlet.

9. A transmission, characterized in that, It includes a rear housing and a transmission ventilation structure as described in any one of claims 1 to 8, the rear housing being used to cover the reducer cavity.

10. A vehicle, characterized in that, The transmission as described in claim 9 is used.

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