Ventilation plug, transmission

Abstract

The present application belongs to the parts of transmission, in order to solve the technical problems that the existing vent plug structure is difficult to meet the current and future transmission requirements in terms of dust prevention, water vapor prevention, oil blocking, space and the like, a vent plug and a transmission are provided. The vent plug comprises a plug cap and a core body. The plug cap is sleeved on the upper end of the core body, and the lower end of the core body is sealingly installed in the vent plug hole of the transmission housing. The core body is in a hollow columnar shape, and the hollow structure inside the core body is referred to as a cavity. A first vent hole, a second vent hole and an oil return hole are arranged on the side wall of the core body, at least one first annular boss and at least one second annular boss are arranged on the outer wall of the core body, and a vent passage is arranged on the side wall of the upper end of the core body. A first notch is arranged on the first annular boss, and a second notch is arranged on the second annular boss. The cavity lower end, the first vent hole, the first notch, the second vent hole, the cavity upper end, the vent passage and the second notch are sequentially communicated to form a gas passage.

Description

Technical Field

[0001] This invention pertains to components of a transmission, specifically a breather plug and a transmission. Background Technology

[0002] During transmission operation, the internal temperature of the transmission housing continuously rises, and the internal air pressure also increases accordingly. Under continuous high pressure, the sealing performance of transmission components, such as oil seals, gradually deteriorates, leading to oil leakage. To address this issue, transmissions are equipped with breather plugs. The three main functions of a breather plug are: 1. To connect the transmission's internal components with the outside atmosphere, maintaining pressure balance between the two environments; 2. To prevent dust or moisture from entering the transmission; 3. To prevent oil mist from escaping the transmission, reducing lubricant loss and preventing oil mist from polluting the atmosphere. Therefore, in addition to allowing ventilation, the breather plug in a car transmission should also provide dust and oil leak prevention.

[0003] Currently, the main problems with breather plugs on the market are as follows:

[0004] 1. The effect of preventing external dust and moisture from entering the transmission is not good;

[0005] 2. When the transmission gears are running at high speed, the gear oil is easily splashed due to the agitation, causing some oil to splash around the breather plug. If the breather plug does not have sufficient oil-blocking function, oil leakage will occur.

[0006] 3. An oil baffle structure needs to be installed inside the transmission housing, which will affect the space available for the transmission.

[0007] With the advent of the electrification era, automobiles have increasingly higher requirements for the space and sealing performance of transmissions, and the existing transmission breather structure can no longer meet the current and future transmission requirements. Summary of the Invention

[0008] In order to solve the technical problems that existing vent plug structures are difficult to meet the requirements of current and future transmissions in terms of dust prevention, water vapor prevention, oil blocking, and space, this invention provides a vent plug and a transmission.

[0009] To achieve the above objectives, the present invention employs the following technical solution:

[0010] A vent plug, comprising a cap and a core;

[0011] The cap is fitted onto the upper end of the core, and the lower end of the core is sealed and installed inside the vent hole of the transmission housing;

[0012] The core is hollow columnar, and the hollow structure inside the core is referred to as a cavity. The lower end of the cavity is connected to the vent hole of the transmission housing.

[0013] The core has a first vent hole, a second vent hole, and an oil return hole on its side wall, with the oil return hole located at the bottom. The outer wall of the core has at least one first annular boss and at least one second annular boss. The upper side wall of the core has a ventilation channel. The first annular boss has a first notch, and the second annular boss has a second notch.

[0014] The lower end of the cavity, the first vent, the first opening, the second vent, the upper end of the cavity, the ventilation channel, and the second opening are sequentially connected to form a gas passage, which then connects to the external atmosphere.

[0015] Furthermore, the outer wall of the core is also provided with a third annular protrusion and a buckle;

[0016] The third annular boss is located axially between the first annular boss and the second annular boss, and the buckle is located on the lower end face of the core.

[0017] The lower end face of the third annular boss abuts against and seals the upper end face of the side wall of the vent hole of the transmission housing, and the upper end face of the buckle abuts against the lower end face of the side wall of the vent hole of the transmission housing.

[0018] A gap is left between the lower end face of the plug and the upper end face of the third annular protrusion, forming a channel connecting the gas passage with the external atmosphere.

[0019] Furthermore, the buckle is located at the lower end face of the core, and multiple telescopic grooves are provided circumferentially on the lower end face of the core.

[0020] Furthermore, the plug cap is provided with a first limiting step, and the cavity sidewall is provided with a second limiting step;

[0021] The first limiting step and the second limiting step cooperate to limit the cap axially and radially relative to the core; a gap is left between the first limiting step and the second limiting step to form a channel between the upper end of the cavity in the gas passage and the ventilation channel.

[0022] Furthermore, multiple grooves are evenly opened along the circumference on the upper surface of the core to form the ventilation channel.

[0023] Furthermore, the stopper includes a cap body and a limiting body connected to the inside of the cap body;

[0024] The inner top surface of the cap body abuts against the upper end surface of the core body, and the limiting body extends into the cavity;

[0025] The first limiting step is disposed on the outer wall of the limiting body;

[0026] A gap is left between the lower end face of the cap and the upper end face of the third annular protrusion, forming a channel connecting the gas passage with the external atmosphere.

[0027] Furthermore, there are two of each of the first and second annular bosses. The first annular boss abuts against the inner wall of the vent hole in the transmission housing, and the second annular boss abuts against the inner wall of the cap.

[0028] The first and second notches are provided in multiples and are evenly distributed along the circumference of the corresponding annular bosses;

[0029] The first notches on the two first annular protrusions are staggered; the second notches on the two second annular protrusions are staggered.

[0030] Furthermore, a fourth annular protrusion is provided on the lower end sidewall of the core;

[0031] The lower end face of the fourth annular boss abuts against the mounting step on the inner wall of the vent hole of the transmission housing.

[0032] Furthermore, both the first vent hole and the oil return hole are located on the fourth annular boss.

[0033] The present invention also proposes a transmission, including a transmission body and a vent plug;

[0034] The vent plug is the vent plug described above.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] 1. This invention proposes a vent plug. Through ingenious design of the core structure, a gas passage is formed, consisting of the lower end of the cavity, a first vent hole, a first notch, a second vent hole, the upper end of the cavity, a venting channel, and a second notch, resulting in a labyrinthine venting channel. Simultaneously, the lower end face of the first annular protrusion allows oil vapor to condense into liquid, flowing back into the transmission cavity through the oil return port. This allows the vent plug to both allow ventilation and prevent oil evaporation within the transmission cavity. Furthermore, the cap not only facilitates ventilation but also, through the labyrinthine venting channel, prevents external dust and moisture from entering the transmission. Therefore, by integrating ventilation, oil blocking, and dust prevention functions into the vent plug, compared to existing technologies, there is no need to design an oil blocking structure inside the transmission housing, further optimizing the transmission's mounting space and meeting the requirements of current and future transmissions.

[0037] 2. In this invention, the core and the transmission housing are sealed by means of a third annular boss buckle to prevent oil and gas leakage, and this can be achieved by adjusting the core's own structure.

[0038] 3. In this invention, a telescopic groove is provided on the lower end face of the core, which facilitates the installation of the core into the vent hole of the transmission housing and allows the buckle to pass through the vent hole of the transmission housing.

[0039] 4. In this invention, the axial and radial positions of the plug cap are limited by the cooperation of the first limiting step and the second limiting step, which ensures the installation reliability of the plug cap and does not affect the air blocking effect.

[0040] 5. In this invention, there are two of each of the first and second annular bosses, and the first notches of the two first annular bosses are staggered, as are the second notches of the two second annular bosses. When the gas is ventilated, it passes through the two first annular bosses and the third annular boss. Each time the gas passes through a boss, the oil and gas can be sublimated into liquid and flow back to the transmission cavity. After three separations, the evaporation of oil in the transmission cavity can be further effectively reduced.

[0041] 6. The present invention also proposes a transmission that uses the aforementioned vent plug, which has the effects of the aforementioned vent plug, and can improve the sealing performance and service life of the transmission sealing parts, and reduce the occurrence of oil leakage. Attached Figure Description

[0042] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0044] Figure 2 This is a schematic diagram of the core structure in Embodiment 2 of the present invention;

[0045] Figure 3 This is a schematic diagram of the cap structure in Embodiment 2 of the present invention;

[0046] Figure 4 This is a partial structural diagram of the transmission housing in Embodiment 2 of the present invention;

[0047] Figure 5 This is a schematic diagram of gas flow in Embodiment 2 of the present invention; wherein, the arrow indicates the direction of gas flow.

[0048] Wherein: 1-core body, 2-plug cap, 201-cap body, 202-limiting body, 3-transmission housing vent plug hole, 4-clasp, 5-oil return hole, 6-first vent hole, 7-first limiting step, 8-second limiting step, 9-second annular boss, 10-first notch, 11-second vent hole, 12-third annular boss, 13-first annular boss, 14-second notch, 15-fourth annular boss, 16-installation step, 17-venting channel, 18-top surface inside the cap body, 19-telescopic groove, 20-transmission housing. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0050] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0051] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0052] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention 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, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0053] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0054] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0055] This invention proposes a cleverly designed vent plug that integrates ventilation, dust prevention, water blocking, and oil blocking functions into a single vent plug. This eliminates the need for a dedicated oil blocking structure inside the transmission housing, optimizes the transmission's mounting space, reduces casting complexity, and improves dust prevention, water blocking, and oil blocking effects.

[0056] The present invention will be further described in detail below with reference to the accompanying drawings and some embodiments thereof:

[0057] Example 1

[0058] A vent plug includes a cap 2 and a core 1. The cap 2 is fitted onto the upper end of the core 1, and the lower end of the core 1 is sealed within a vent hole 3 in the transmission housing to prevent oil vapor from escaping through other channels and causing the transmission fluid to evaporate. The core 1 is a hollow column, and its internal hollow structure is referred to as a cavity. The lower end of the cavity communicates with the interior of the vent hole 3 in the transmission housing. The sidewall of the core 1 is provided with a first vent hole 6, a second vent hole 11, and an oil return hole 5, with the oil return hole 5 located at the bottom. The outer wall of the core 1 is provided with at least one first annular boss 13 and at least one second annular boss 9, and the upper sidewall of the core 1 is provided with a venting channel 17. The first annular boss 13 is provided with a first notch 10, and the second annular boss 9 is provided with a second notch 14. The number of the first annular boss 13 and the second annular boss 9 can be adjusted according to actual needs. If the gas flow path is more complex, the number can be increased accordingly. If the processing difficulty, cost and ventilation efficiency are considered, the number of the first annular boss 13 and the second annular boss 9 can be reduced.

[0059] Finally, a gas passage is formed by sequentially connecting the lower end of the cavity, the first vent 6, the first opening 10, the second vent 11, the upper end of the cavity, the ventilation channel 17, and the second opening 14. When ventilation is performed, the gas flows along the gas passage. The second opening 14 connects with the external atmosphere, allowing the gas to eventually reach the external atmosphere.

[0060] Example 2

[0061] like Figure 1The diagram shows a preferred embodiment of a transmission according to the present invention, comprising a transmission body and a vent plug. The vent plug includes a cap 2 and a core 1. The transmission body has a transmission housing vent plug hole 3 for installing the vent plug. Figure 1 A portion of the transmission housing 20 is shown, used only to illustrate the transmission housing vent hole 3.

[0062] like Figure 2 As shown, the outer wall of the core 1 is provided with two first annular protrusions 13, two second annular protrusions 9, one third annular protrusion 12, one buckle 4, and one fourth annular protrusion 15.

[0063] The third annular boss 12 is located axially between the two first annular bosses 13 and the two second annular bosses 9. The buckle 4 is located on the lower end face of the core 1. The fourth annular boss 15 is adjacent to the first annular boss 13 and is located below the first annular boss 13 near the lower end of the core 1.

[0064] The lower end face of the third annular boss 12 abuts against and seals the upper end face of the side wall of the vent hole 3 in the transmission housing. The upper end face of the buckle 4 abuts against the lower end face of the side wall of the vent hole 3 in the transmission housing for axial positioning. The lower end face of the fourth annular boss 15 abuts against the mounting step 16 on the inner wall of the vent hole 3 in the transmission housing. Figure 4 As shown, the mounting step 16 is a structure within the transmission housing 20. Additionally, the first annular boss 13 abuts against the inner wall of the transmission housing vent hole 3, and the second annular boss 9 abuts against the inner wall of the cap 201, preventing gas from passing through. The third annular boss 12, the fourth annular boss 15, and the first annular boss 13 ensure that the core 1 is stably and reliably installed within the transmission housing vent hole 3. The third annular boss 12 and the latch 4 position and seal the core 1. Because the latch 4 is provided and located at the lower end face of the core 1, four circumferential expansion grooves 19 are formed on the lower end face of the core 1. When installing the core 1 into the transmission housing vent hole 3, the lower end of the core 1 can retract inward due to the expansion grooves 19, allowing the latch 4 to pass through the transmission housing vent hole 3 to reach the installation position. In other embodiments of the present invention, the number of expansion grooves 19 can be reasonably adjusted to ensure that the lower end of the core 1 can retract during installation and expand after installation, while also ensuring the structural reliability of the lower end of the core 1. Four first notches 10 are evenly arranged around the first annular boss 13, and four second notches 14 are evenly arranged around the second annular boss 9. This number can also be adjusted according to actual needs. Multiple grooves are evenly formed around the upper surface of the core 1 to create ventilation channels 17.

[0065] The second vent 11 is located between the third annular boss 12 and the first annular boss 13 near the upper end of the core 1, and is close to the first annular boss 13. The first vent 6 and the oil return hole 5 are both located on the fourth annular boss 15, which is more conducive to oil return.

[0066] like Figure 3 As shown, the cap 2 includes a cap body 201 and a limiting body 202 connected inside the cap body 201. The inner top surface 18 of the cap body abuts against the upper end surface of the core 1. The limiting body 202 extends into the cavity. A first limiting step 7 is provided on the outer wall of the limiting body 202, and a second limiting step 8 is provided on the side wall of the cavity. The first limiting step 7 and the second limiting step 8 cooperate to limit the cap 2 axially and radially relative to the core 1. As a preferred embodiment, the first limiting step 7 is a conical surface on the outer wall of the limiting body 202, and the second limiting step 8 is a protrusion on the side wall of the cavity, with the protrusion located on the conical surface. In other embodiments of the present invention, the specific implementation of the first limiting step 7 and the second limiting step 8 may differ, as long as the limiting is achieved. In addition, a gap is left between the first limiting step 7 and the second limiting step 8, and a gap is left between the lower end surface of the cap body 201 and the upper end surface of the third annular protrusion 12.

[0067] like Figure 5 The arrows indicate the direction of gas flow. The gas flow process during ventilation in Example 2 is as follows:

[0068] Gas from inside the transmission housing 20 enters the core 1 through the lower end of the cavity, flows out through the first vent 6, passes through the first notch 10 of the two first annular protrusions 13 from bottom to top, and re-enters the cavity through the second vent 11. When the oil and gas inside the transmission housing 20 pass between the two first annular protrusions 13 and between the first annular protrusion 13 and the second annular protrusion 12, the oil and gas can condense into liquid at the lower end surfaces of the two first annular protrusions 13 and the second annular protrusion 12, and flow back into the transmission housing 20 through the oil return hole 5. The three layers of protrusions can separate the oil and gas entering the vent plug three times, thereby effectively reducing the evaporation of oil inside the transmission housing 20. Gas passes through the gap between the first limiting step 7 and the second limiting step 8 in the cavity, flows out of the cavity through the vent channel 17, passes through the second notch 14 of the two second annular protrusions 9 in sequence, and finally is discharged to the atmosphere through the gap between the lower end surface of the cap 201 and the upper end surface of the third annular protrusion 12.

[0069] This invention employs a clever structural design with a labyrinthine ventilation path. While allowing ventilation, it prevents external dust and moisture from entering the transmission, achieving ventilation, dust prevention, and water blocking functions. Furthermore, by integrating ventilation, dust prevention, water blocking, and oil blocking functions into the vent plug, a dedicated oil blocking structure is no longer needed inside the transmission housing 20, thus optimizing the transmission's mounting space.

[0070] The structure of the vent plug in Embodiment 2 of the present invention can also be used as a standalone embodiment of the vent plug. The vent plug structure in Embodiment 1 is used in a transmission, and correspondingly, a basic embodiment of a transmission according to the present invention can be obtained. Furthermore, in other embodiments of the present invention, the limiting method, installation method, number of first annular protrusions 13, and number of second annular protrusions 9 in the vent plug can be adjusted.

[0071] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A vent plug, characterized in that: Includes a cap (2) and a core (1); The cap (2) is fitted onto the upper end of the core (1), and the lower end of the core (1) is sealed and installed inside the vent hole (3) of the transmission housing; The core (1) is hollow columnar, and the hollow structure inside the core (1) is called a cavity. The cavity is connected to the vent hole (3) of the transmission housing. The core (1) has a first vent (6), a second vent (11) and an oil return hole (5) on its side wall, with the oil return hole (5) located at the bottom. The core (1) has at least one first annular boss (13) and at least one second annular boss (9) on its outer wall. The upper side wall of the core (1) has a ventilation channel (17). The first annular boss (13) has a first notch (10), and the second annular boss (9) has a second notch (14). The outer wall of the core (1) is also provided with a third annular boss (12) and a buckle (4). The third annular boss (12) is located axially between the first annular boss (13) and the second annular boss (9), and the buckle (4) is located on the lower end face of the core (1). The lower end face of the third annular boss (12) abuts against and seals the upper end face of the side wall of the vent hole (3) of the transmission housing, and the upper end face of the buckle (4) abuts against the lower end face of the side wall of the vent hole (3) of the transmission housing. A gap is left between the lower end face of the plug (2) and the upper end face of the third annular protrusion (12) to form a channel connecting the gas passage with the external atmosphere. The lower end of the cavity, the first vent (6), the first opening (10), the second vent (11), the upper end of the cavity, the ventilation channel (17), and the second opening (14) are connected in sequence to form a gas passage, which is then connected to the external atmosphere.

2. The vent plug according to claim 1, characterized in that: The buckle (4) is located at the lower end face of the core (1), and multiple telescopic grooves (19) are provided on the lower end face of the core (1) along the circumferential direction.

3. A vent plug according to claim 1 or 2, characterized in that: The plug cap (2) is provided with a first limiting step (7), and the cavity sidewall is provided with a second limiting step (8). The first limiting step (7) and the second limiting step (8) cooperate to limit the cap (2) axially and radially relative to the core (1); a gap is left between the first limiting step (7) and the second limiting step (8) to form a channel between the upper end of the cavity in the gas passage and the ventilation channel (17).

4. A vent plug according to claim 3, characterized in that: Multiple grooves are evenly opened on the upper surface of the core (1) along the circumference to form the ventilation channel (17).

5. A vent plug according to claim 4, characterized in that: The plug (2) includes a cap body (201) and a limiting body (202) connected inside the cap body (201); The inner top surface (18) of the cap body abuts against the upper end surface of the core (1), and the limiting body (202) extends into the cavity; The first limiting step (7) is disposed on the outer wall of the limiting body (202); A gap is left between the lower end face of the cap body (201) and the upper end face of the third annular protrusion (12), forming a channel connecting the gas passage with the external atmosphere.

6. A vent plug according to claim 5, characterized in that: The first annular boss (13) and the second annular boss (9) are provided in twos. The first annular boss (13) abuts against the inner wall of the vent hole (3) of the transmission housing, and the second annular boss (9) abuts against the inner wall of the cap (201). The first notch (10) and the second notch (14) are each provided with multiple notches, and are evenly distributed along the circumference of the corresponding annular boss; The first notches (10) on the two first annular bosses (13) are staggered; the second notches (14) on the two second annular bosses (9) are staggered.

7. A vent plug according to claim 6, characterized in that: The lower end sidewall of the core (1) is provided with a fourth annular boss (15). The lower end face of the fourth annular boss (15) abuts against the mounting step (16) on the inner wall of the vent hole (3) of the transmission housing.

8. A vent plug according to claim 7, characterized in that: The first vent (6) and the oil return hole (5) are both located on the fourth annular boss (15).

9. A transmission, comprising a transmission body and a breather plug; characterized in that: The vent plug is the vent plug according to any one of claims 1 to 8.

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