Gearbox breather plug and mounting structure thereof

Abstract

This invention discloses a transmission vent plug and its installation structure. The transmission vent plug includes a base, a lower connecting part coaxially fixed within the base, and an upper connecting part coaxially fixed to the top of the base. An exhaust channel is formed on the side surface of the base. Both the lower and upper connecting parts have interconnected labyrinthine oil-gas channels. A filter screen, communicating with the labyrinthine oil-gas channels and used for filtering and blocking oil and gas, is fixed within the integral structure formed by the base, lower connecting part, and upper connecting part. The transmission vent plug and its installation structure designed in this invention integrate filtering, blocking, recirculation, and exhaust functions. While the vent plug separates and recirculates lubricating oil and gas, the exhaust channel inside the transmission cavity remains connected to the atmosphere, relieving pressure within the transmission cavity.

Description

Technical Field

[0001] This invention relates to the field of automotive parts technology, specifically to a transmission breather plug and its mounting structure. Background Technology

[0002] The primary function of a vehicle's transmission is to change the gear ratio, expanding the range of torque and speed variation for the drive wheels to adapt to frequently changing driving conditions, while allowing the engine to operate at higher power and lower fuel consumption. Transmissions typically incorporate multi-stage gear transmissions, using different gear combinations to generate speed and torque changes. Transmission fluid lubricates and cleans the various components within the transmission and ensures timely and efficient torque transmission. The internal air pressure of the transmission housing changes with operating conditions. During operation, the gear transmission generates significant heat, causing the air inside the housing to expand and increasing the internal pressure. Conversely, when the transmission stops operating, the internal pressure gradually decreases. To prevent the thermal expansion of the internal air from damaging the housing's seals, a vent plug is usually installed on the transmission housing to maintain pressure balance between the inside and outside of the transmission.

[0003] Patent application number 202123058883.6, entitled "A vent plug for preventing water ingress and oil spraying in a transmission", discloses a vent plug for preventing water ingress and oil spraying in a transmission. It includes a main structure, a first oil baffle plate, an O-ring, a second oil baffle plate, a vent membrane paper fixing seat, a vent membrane paper, and an end cap. The main structure has a boss in the middle, one side of which has a threaded structure, and the other end is fitted with an end cap. The main structure has a first oil baffle plate and a second oil baffle plate at one end of its inner cavity, and a vent membrane paper at the other end. The vent membrane paper is fixed by the vent membrane paper fixing seat.

[0004] Patent application number 202220685022.6, entitled "A Breather Plug and a Transmission", discloses a breather plug and a transmission. The breather plug includes a sleeve, a breather cap, and a breather tube. The sleeve includes a first connecting tube for connecting to the transmission and a second connecting tube integrally connected to the first connecting tube. The breather cap is integrally connected to the breather tube and detachably connected to the second connecting tube through the breather tube. The breather cap includes an inner tube extending outward from one end of the breather tube and an outer cover covering the end face of the inner tube. The outer cover and the outer side wall of the inner tube are spaced apart to form a gap. The inner tube has a plurality of vent holes arranged in a ring array facing the gap. The diameter of the vent holes located inside the inner tube is larger than the diameter of the vent holes located outside the inner tube.

[0005] Current transmission breather plugs are typically single-channel designs with one inlet and one outlet. When lubricating oil vapor enters the intake channel, and the channel is blocked while lubricating oil remains in the breather plug, the lubricating oil flows out of the breather plug and cannot flow back into the transmission. Due to space constraints within the transmission, the breather plug inlet is relatively close to gears and other oil-agitating components. When the gears agitate the oil, they can directly throw lubricating oil into the breather plug, so a barrier structure is placed around the breather plug. When the transmission uses pneumatic shifting, or is equipped with a pneumatic shifting power take-off, a retarder, or an air compressor, blow-by frequently occurs. High-pressure air from the air circuit enters the transmission, causing the internal pressure to rise, and lubricating oil flows out along the breather plug channel, resulting in transmission oil leakage. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the above-mentioned background technology and provide a transmission breather plug and its installation structure that can block, filter, and reflux oil and gas and prevent transmission blow-by and oil leakage.

[0007] To achieve this objective, the gearbox vent plug designed in this invention includes a base, a lower connecting part coaxially fixed within the base, and an upper connecting part coaxially fixed to the top of the base. An exhaust channel is provided on the side surface of the base. Both the interior of the lower connecting part and the interior of the upper connecting part are provided with interconnected labyrinthine oil-gas channels. A filter screen, communicating with the labyrinthine oil-gas channels and used for filtering and blocking oil and gas, is fixed within the integral structure formed by the base, the lower connecting part, and the upper connecting part.

[0008] Furthermore, a filter screen is fixed to the bottom of both the upper connecting part and the bottom of the lower connecting part.

[0009] Furthermore, the lower connecting part includes a cylindrical lower connecting column, and the upper connecting part includes a cylindrical upper connecting column. The bottom of the lower connecting column is coaxially provided with a lower filter screen mounting hole, and the bottom of the upper connecting column is coaxially provided with an upper filter screen mounting hole. The filter screen includes a lower filter screen coaxially fixed in the lower filter screen mounting hole and an upper filter screen coaxially fixed in the upper filter screen mounting hole.

[0010] Furthermore, the lower filter screen has circumferentially spaced lower circumferential oil passage holes and a lower central oil passage hole in the middle; the upper filter screen has circumferentially spaced upper circumferential oil passage holes and an upper central oil passage hole in the middle; the diameter of the lower central oil passage hole is larger than the diameter of the upper central oil passage hole.

[0011] Furthermore, the lower connecting column is provided with a lower labyrinthine oil and gas channel communicating with the lower circumferential oil passage, and the upper connecting column is provided with an upper labyrinthine oil and gas channel communicating with the upper circumferential oil passage.

[0012] Furthermore, a lower insertion column for inserting into the base is coaxially fixed at the top of the lower connecting column. The lower insertion column and the lower connecting column are an integral structure. The middle part of the lower connecting part is provided with a lower axial oil passage hole that communicates with the lower middle oil passage hole.

[0013] Furthermore, the base includes a base ring coaxially fixed to the bottom of the upper connecting column. There is an oil passage between the top surface of the base ring and the bottom surface of the upper connecting column, which communicates with the circumferential oil passage hole. A base cylinder integrally formed with the base ring is coaxially fixed to the lower center of the base ring. A base buckle that cooperates with the lower insertion column is coaxially fixed inside the base cylinder.

[0014] Furthermore, the base buckle has a buckle hole in the middle that mates with the lower insertion column, and buckle grooves are circumferentially spaced around the buckle hole and arranged radially along the buckle hole. The top of the lower insertion column is coaxially fixedly connected to a lower boss that is an integral part of the lower insertion column.

[0015] Furthermore, the upper connecting part also includes an upper insert column coaxially fixed to the center of the upper connecting column. The center of the upper connecting part is coaxially provided with an upper axial oil passage hole communicating with the upper middle oil passage hole. The top of the upper insert column is coaxially fixed with an upper boss that is an integral structure therewith.

[0016] Furthermore, the transmission vent plug mounting structure includes a transmission and the aforementioned transmission vent plug. The transmission has a vent plug mounting hole, and the base is disposed within the vent plug mounting hole. The lower connecting part is located inside the transmission, and the upper connecting part is located outside the transmission. The top of the upper connecting part is connected to a corrugated return pipe that communicates with the labyrinthine oil and gas passage of the upper connecting part. The two ends of the exhaust passage opened on the side surface of the base are located inside and outside the transmission, respectively.

[0017] The beneficial effects of this invention are as follows: The vent plug and its mounting structure for the transmission designed in this invention integrate filtering, blocking, reflux, and venting functions. When lubricating oil is directly thrown to the vicinity of the vent plug's inlet by rotating parts such as gears, the lower part of the vent plug blocks the lubricating oil. When the oil-gas mixture enters the vent plug, it is filtered by a filter screen, then separated and refluxed through a labyrinthine oil-gas channel, and finally separated and refluxed through an adjustable-length corrugated reflux pipe. While the vent plug separates and refluxes the lubricating oil and gas, the venting channel inside the transmission cavity remains connected to the atmosphere, relieving pressure within the transmission cavity. This significantly reduces the probability of a large amount of lubricating oil entering the vent plug's inlet due to installation space limitations, avoiding problems such as increased oil pressure in the transmission cavity and vent plug leakage caused by blow-by. The vent plug has a compact structure, large displacement, and is easy to install and remove via a snap-fit ​​structure. Attached Figure Description

[0018] Figure 1 This is an axial cross-sectional view of the gearbox breather plug in this invention;

[0019] Figure 2 This is an axial cross-sectional view of the lower connecting part in this invention;

[0020] Figure 3 This is a bottom view of the lower connecting part in this invention;

[0021] Figure 4 This is an axial cross-sectional view of the base in this invention;

[0022] Figure 5 This is a bottom view of the base in this invention;

[0023] Figure 6 This is a top view of the base in this invention;

[0024] Figure 7 This is an axial cross-sectional view of the upper connecting part in this invention;

[0025] Figure 8 This is a top view of the lower filter screen in this invention;

[0026] Figure 9 This is a top view of the upper filter screen in this invention;

[0027] Figure 10 This is a front view of the corrugated return pipe connecting the gearbox breather plug in this invention;

[0028] Figure 11 This is a schematic diagram of the installation structure of the gearbox vent plug in this invention;

[0029] Figure 12 This is a schematic diagram of the flow of oil and gas into the vent plug in this invention. Figure 1;

[0030] Figure 13 This is a schematic diagram of the flow of oil and gas into the vent plug in this invention. Figure 2 ;

[0031] Figure 14 This is a schematic diagram of the flow of oil and gas into the vent plug in this invention. Figure 3 ;

[0032] Figure 15 This is a schematic diagram of the exhaust flow direction of the vent plug in this invention;

[0033] Figure 16 This is a schematic diagram illustrating the flow of oil and gas returning to the gearbox via the breather plug in this invention. Figure 1 ;

[0034] Figure 17 This is a schematic diagram illustrating the flow of oil and gas returning to the gearbox via the breather plug in this invention. Figure 2 ;

[0035] Wherein, 1—lower connecting part (1.1—lower connecting column, 1.2—lower insert column), 2—base (2.1—base ring, 2.2—base cylinder, 2.3—base buckle), 3—lower connecting part (3.1—upper connecting column, 3.2—upper insert column), 4—lower filter screen (4.1—lower circumferential oil passage hole, 4.2—lower middle oil passage hole), 5—upper filter screen (5.1—upper circumferential oil passage hole, 5.2—upper middle oil passage hole). 6—Lower labyrinth oil-gas passage, 7—Upper labyrinth oil-gas passage, 8—Lower axial oil passage, 9—Oil passage, 10—Snap-in hole, 11—Snap-in groove, 12—Lower boss, 13—Upper axial oil passage, 14—Upper boss, 15—Lower filter mounting hole, 16—Upper filter mounting hole, 17—Gearbox, 18—Ventilator mounting hole, 19—Corrugated return pipe, 20—Exhaust groove, 21—Exhaust passage. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. 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. In the description of the present invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and 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.

[0037] like Figure 1The gearbox vent plug shown in Figure 9 includes a base 2, a lower connecting part 1 coaxially fixed inside the base 2, and an upper connecting part 3 coaxially fixed to the top of the base 2. An exhaust channel 21 is provided on the side surface of the base 2. Both the interior of the lower connecting part 1 and the interior of the upper connecting part 3 are provided with interconnected labyrinth-type oil and gas channels. A filter screen is fixed inside the integral structure composed of the base 2, the lower connecting part 1, and the upper connecting part 3, which is connected to the labyrinth-type oil and gas channels and is used to filter and block oil and gas.

[0038] Specifically, a filter screen is fixed to the bottom of both the upper connecting part 3 and the lower connecting part 1. The lower connecting part 1 includes a cylindrical lower connecting column 1.1, with a lower filter screen mounting hole 15 coaxially formed at the bottom of the lower connecting column 1.1. The filter screen includes a lower filter screen 4 coaxially fixed within the lower filter screen mounting hole 15. The lower filter screen 4 has lower circumferential oil passage holes 4.1 spaced apart circumferentially, and a lower central oil passage hole 4.2 formed in the middle. A lower insertion column 1.2 for insertion into the base 2 is coaxially fixed to the top of the lower connecting column 1.1. The lower insertion column 1.2 and the lower connecting column 1.1 are integrally formed. A lower axial oil passage hole 8 communicating with the lower central oil passage hole 4.2 is formed along the axial direction in the middle of the lower connecting part 1. Figure 3 As shown, a lower labyrinthine oil and gas channel 6 is provided inside the lower connecting column 1.1, which communicates with the lower circumferential oil passage 4.1.

[0039] The upper connecting part 3 includes a cylindrical upper connecting column 3.1. An upper filter screen mounting hole 16 is coaxially formed at the bottom of the upper connecting column 3.1. The filter screen includes an upper filter screen 5 coaxially fixed within the upper filter screen mounting hole 16. The upper filter screen 5 has circumferentially spaced oil passage holes 5.1 and an upper-middle oil passage hole 5.2 in its center. An upper labyrinthine oil-gas passage 7 communicating with the circumferentially spaced oil passage holes 5.1 is formed inside the upper connecting column 3.1. Figure 3 (Same). The upper connecting column 3.1 is coaxially fixed with the upper insert column 3.2. The upper connecting part 3 is coaxially provided with an upper axial oil passage 13 that communicates with the upper middle oil passage 5.2. The top of the upper insert column 3.2 is coaxially fixed with an upper boss 14 that is an integral part therewith.

[0040] like Figure 8 As shown in Figure 9, the diameter of the lower middle oil passage hole 4.2 is larger than the diameter of the upper middle oil passage hole 5.2.

[0041] The base 2 includes a base ring 2.1 coaxially fixed to the bottom of the upper connecting column 3.1. An oil passage 9 communicating with a circumferential oil passage hole 5.1 exists between the top surface of the base ring 2.1 and the bottom surface of the upper connecting column 3.1. A base cylinder 2.2, integrally formed with the base ring 2.1, is coaxially fixed to the lower center of the base ring 2.1. A base buckle 2.3, co-located with the lower insert column 1.2, is coaxially fixed inside the base cylinder 2.2. A buckle hole 10, co-located with the lower insert column 1.2, is provided in the middle of the base buckle 2.3. Buckle grooves 11, arranged radially along the buckle hole 10, are circumferentially spaced around the buckle hole 10. A lower boss 12, integrally formed with the lower insert column 1.2, is coaxially fixed to the top of the lower insert column 1.2.

[0042] like Figure 10 The installation structure of the transmission vent plug shown in Figure 11 includes a transmission 17 and the aforementioned transmission vent plug. The transmission 17 has a vent plug mounting hole 18. The base 2 is disposed in the vent plug mounting hole 18. The lower connecting part 1 is located inside the transmission 17, and the upper connecting part 3 is located outside the transmission 17. The top of the upper connecting part 3 is connected to a corrugated return pipe 19 that communicates with the labyrinthine oil and gas passage of the upper connecting part 3. The two ends of the exhaust passage 21 opened on the side surface of the base 2 are located inside and outside the transmission 17, respectively.

[0043] In this invention, lubricating oil cannot be directly flung into the breather plug by the gears; the labyrinthine oil-gas passage within the breather plug serves as a long exhaust channel for oil and gas. When very little lubricating oil-gas enters the breather plug, the gearbox's intake and exhaust process is as follows: Figure 12 As shown, the oil return method is as follows Figure 16 As shown; as more lubricating oil gas enters the breather plug, the transmission exhaust method changes. Figure 12 , Figure 13 and Figure 14 These combinations of exhaust methods, and the conversion of the oil return method... Figure 16 and Figure 17 The two methods shown are combined in this way.

[0044] The transmission breather plug and its mounting structure designed in this invention integrate filtering, blocking, backflow, and venting functions. When lubricating oil is directly thrown to the vicinity of the breather plug inlet by rotating parts such as gears, the lower part of the breather plug blocks the lubricating oil. When the oil-gas mixture enters the breather plug, it is filtered by a filter screen, then separated and backflowed through a labyrinthine oil-gas channel, and finally separated and backflowed through an adjustable-length corrugated backflow pipe 19. While the breather plug separates and backflows the lubricating oil and gas, the venting channel inside the transmission cavity is always connected to the atmosphere, relieving pressure inside the transmission cavity. This greatly reduces the probability of a large amount of lubricating oil entering the breather plug inlet due to installation space limitations, and avoids problems such as increased oil pressure inside the transmission cavity and oil leakage from the breather plug due to blow-by. The breather plug has a compact structure, large displacement, and is easy to install and remove through a snap-fit ​​structure.

[0045] It should be noted that the above description of the technical solutions is exemplary, and this specification may be embodied in different forms and should not be construed as limiting itself to the technical solutions set forth herein. Rather, providing these descriptions will ensure that the disclosure of this invention is thorough and complete, and will fully convey the scope of this specification to those skilled in the art. Furthermore, the technical solutions of this invention are defined only by the scope of the claims. When using terms such as "comprising," "having," and "including" as described in this specification, there may also be another part or other components, and the terms used are generally singular but may also represent plural forms. It should be pointed out that although various different components may appear and be described in this specification using terms such as "first," "second," "top," "bottom," "one side," "the other side," "one end," "the other end," etc., these components and parts should not be limited by these terms. These terms are only used to distinguish one component and part from another component and part. For example, without departing from the scope of this specification, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component; top and bottom components may, in certain cases, be interchanged or converted; components at one end and at the other end may have the same or different performance characteristics.

[0046] Finally, it should be noted that the above embodiments are merely representative examples of the present invention. Obviously, the present invention is not limited to the above embodiments and many variations are possible. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention should be considered within the protection scope of the present invention.

Claims

1. A gearbox breather plug, characterized by: The application relates to a filter device for filtering and blocking oil gas, which comprises a base (2), a lower connecting part (1) coaxially fixed in the base (2) and an upper connecting part (3) coaxially fixed on the top of the base (2); an exhaust passage (21) is formed in the side surface of the base (2), the inside of the lower connecting part (1) and the inside of the upper connecting part (3) are provided with a labyrinth oil gas passage which is communicated with each other, a filter screen for filtering and blocking oil gas is fixed in the whole structure formed by the base (2), the lower connecting part (1) and the upper connecting part (3) and is communicated with the labyrinth oil gas passage; the lower connecting part (1) comprises a cylindrical lower connecting column (1.1); the upper connecting part (3) comprises a cylindrical upper connecting column (3.1); the filter screen comprises a lower filter screen (4) coaxially fixed in a lower filter screen mounting hole (15) and an upper filter screen (5) coaxially fixed in an upper filter screen mounting hole (16); a plurality of upper circumferential oil passing holes (5.1) are formed in the upper filter screen (5) in a circumferential direction and a plurality of upper middle oil passing holes (5.2) are formed in the middle part; a lower insertion column (1.2) for being inserted into the base (2) is coaxially fixed on the top of the lower connecting column (1.1); the base (2) comprises a base ring (2.1) coaxially fixed on the bottom of the upper connecting column (3.1), an oil passing channel (9) communicated with the upper circumferential oil passing holes (5.1) is formed between the top surface of the base ring (2.1) and the bottom surface of the upper connecting column (3.1), a base cylinder (2.2) integrated with the base ring (2.1) is coaxially fixed and connected to the lower part of the base ring (2.1), and a base buckle (2.3) matched with the lower insertion column (1.2) is coaxially fixed in the base cylinder (2.2).

2. The gearbox breather plug of claim 1, wherein: The bottom of the upper connecting part (3) and the bottom of the lower connecting part (1) are fixed with one filter screen.

3. The gearbox breather plug of claim 2, wherein: A lower filter screen mounting hole (15) is coaxially formed in the bottom of the lower connecting column (1.1), and an upper filter screen mounting hole (16) is coaxially formed in the bottom of the upper connecting column (3.1).

4. The gearbox breather plug of claim 3, wherein: A plurality of lower circumferential oil passing holes (4.1) are formed in the lower filter screen (4) in a circumferential direction, and a plurality of lower middle oil passing holes (4.2) are formed in the middle part; the diameters of the lower middle oil passing holes (4.2) are larger than the diameters of the upper middle oil passing holes (5.2).

5. The gearbox breather plug of claim 4, wherein: A lower labyrinth oil gas passage (6) communicated with the lower circumferential oil passing holes (4.1) is formed in the lower connecting column (1.1), and an upper labyrinth oil gas passage (7) communicated with the upper circumferential oil passing holes (5.1) is formed in the upper connecting column (3.1).

6. The gearbox breather plug of claim 5, wherein: The lower insertion column (1.2) is integrated with the lower connecting column (1.1), and a lower axial oil passing hole (8) communicated with the lower middle oil passing holes (4.2) is formed in the middle part of the lower connecting part (1) along the axial direction.

7. The transmission breather plug of claim 1, wherein: The middle part of the base buckle (2.3) is provided with a buckle hole (10) matched with the lower insertion column (1.2), and the circumferential interval of the buckle hole (10) is connected with a buckle slot (11) arranged along the radial direction of the buckle hole (10), and the top of the lower insertion column (1.2) is coaxially fixedly connected with a lower boss (12) which is an integral structure with the lower insertion column (1.2).

8. The transmission breather plug of claim 4, wherein: The upper connecting part (3) further comprises an upper insertion column (3.2) coaxially fixed in the center of the upper connecting column (3.1), and the center of the upper connecting part (3) is coaxially provided with an upper axial oil passage hole (13) communicated with the upper middle oil passage hole (5.2), and the top of the upper insertion column (3.2) is coaxially fixed with an upper boss (14) which is an integral structure with the upper insertion column (3.2).

9. A mounting structure of a breather plug of a transmission, comprising a transmission (17), characterized by: It further comprises the gearbox breather plug of the above claims 1-8, the gearbox (17) is provided with a breather plug mounting hole (18), the base (2) is arranged in the breather plug mounting hole (18), the lower connecting part (1) is located in the gearbox (17), the upper connecting part (3) is located outside the gearbox (17), the top of the upper connecting part (3) is connected with a corrugated return pipe (19) communicated with the labyrinth oil and gas passage of the upper connecting part (3), and the two ends of the exhaust passage (21) provided on the side surface of the base (2) are located inside and outside the gearbox (17) respectively.

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