CN111720526A

CN111720526A - Liquid blocking and ventilating plug for gearbox

Info

Publication number: CN111720526A
Application number: CN202010596455.XA
Authority: CN
Inventors: 郑重; 王超凡; 黄刚; 张恒超
Original assignee: Hubei University of Technology
Current assignee: Hubei University of Technology
Priority date: 2020-06-28
Filing date: 2020-06-28
Publication date: 2020-09-29
Anticipated expiration: 2040-06-28
Also published as: CN111720526B

Abstract

The invention provides a liquid blocking vent plug for a gearbox, which is characterized by comprising: the lower plug body is internally provided with a first ventilation cavity, the upper surface of the lower plug body is an inclined plane inclined inwards, and the surface of the first ventilation cavity is an ultra-oleophylic surface; the upper plug body is provided with a second vent cavity communicated with the lower plug body, and the inner surface of the upper plug body is an ultra-oleophilic and ultra-hydrophobic surface; the oil baffle plate is arranged in the upper plug body, is positioned at the lower part of the second vent cavity and is densely provided with through holes, the upper surface of the oil baffle plate and the inner surface of each through hole are both super-oleophilic and super-hydrophobic surfaces, and the lower surface of the oil baffle plate is a super-oleophilic surface; a liquid-resistant airway comprising: the device comprises a fixed frame, a plurality of hydrophobic plates arranged in the fixed frame in parallel, and a sealing ring; a third vent cavity is formed between the adjacent hydrophobic plates, the lower part of the third vent cavity is a super oleophilic and super hydrophobic surface, and the upper part of the third vent cavity is a super oleophobic and super hydrophobic surface; and the plug cover is arranged above the upper plug body through bolts, the outer edge of the plug cover extends downwards to form a cover, and a ventilation gap is formed between the plug cover and the upper plug body.

Description

Liquid blocking and ventilating plug for gearbox

Technical Field

The invention belongs to the field of automobile transmission parts, and particularly relates to a liquid-blocking vent plug for a transmission.

Technical Field

The vent plug is one of important parts on gearbox bodies of automobile gearboxes, reduction boxes and the like. No matter the automatic transmission or the manual transmission, in the process of automobile running speed change, heat is generated due to internal mechanical friction, and the temperature in the transmission box body can reach 90-100 ℃. The temperature of the closed gearbox rises and falls alternately, so that the air in the box body expands or contracts along with the temperature, and a large pressure difference is formed between the inside and the outside of the gearbox. Particularly, when the speed is frequently changed in a short time, the high-temperature and high-pressure phenomenon in the gearbox is particularly prominent, if the gearbox is in an abnormal high-temperature and high-pressure state for a long time, the physical performance of lubricating oil can be damaged due to the overhigh temperature, the fluidity of the lubricating oil is reduced, and the mechanical friction and the abrasion in the gearbox are increased; the abnormal high temperature and high pressure can also cause the aging of a rubber sealing element in the gearbox, the leakage of lubricating oil, the slipping of the gearbox and the like, and even the serious consequence of the scrapping of the gearbox. In addition, the inside impurity such as water, dust and dirt that still should insulate of gearbox, if lubricating oil is rotten or the inside impurity such as fatlute that exists of gearbox, can lead to the gearbox to appear the trouble of pause and frustrating, shift gears irregularity.

Therefore, automobile gearboxes on the market are provided with vent plugs so as to relieve temperature and pressure changes in the automobile speed changing process and ensure that the gearboxes can work stably and reliably.

At present, the ventilating plugs used on the gear box have two types, namely a normally open type and a normally closed type. Whether normally open or closed, conventional vent plugs have limitations in certain common automotive operating environments. When the humidity outside the gearbox is high or water mist exists, the traditional vent plug is difficult to separate water vapor in time, and the water vapor in the gearbox is accumulated and condensed. Especially in the gearbox meets water and leads to impurity such as water, dust and dirt to get into the box easily, increase the inside mechanical friction of gearbox and wearing and tearing, lead to the gearbox to appear and pause to be frustrated, shift unsmooth, damage even. Similarly, the traditional breather plug can not timely separate the oil-gas mixture discharged from the gearbox, and trace lubricating oil can be taken away while the oil-gas mixture is discharged, so that the lubricating oil is slowly lost, and finally the gearbox slips. Therefore, the conventional ventilation plug cannot simultaneously take the functions of ventilation and liquid blocking (water inlet prevention and oil drainage prevention).

For example, patent document CN203627743U discloses a vent plug. The ventilation plug is provided with two cylindrical cavities with different diameters, and the oil filter plate is made of a net-shaped metal material, so that the functions of exhausting and air supplementing of the gearbox can be realized. However, the vent plug also has the problem of insufficient liquid blocking (water inlet prevention and oil leakage prevention) functions, cannot timely separate water vapor and oil-gas mixtures, and cannot effectively prevent water vapor accumulation in a tank and slow leakage of lubricating oil. In addition, when the ventilation plug oil baffle plate and the filter layer are at low environmental temperature such as in winter, oil stains are easy to accumulate in the ventilation holes, so that the gas channel is reduced or even blocked, and the function of the ventilation plug is reduced or even lost.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a liquid-blocking vent plug for a transmission, which can achieve both ventilation, liquid-blocking (water-inflow prevention, oil-leakage prevention), and impurity prevention.

In order to achieve the purpose, the invention adopts the following scheme:

the invention provides a liquid blocking vent plug for a gearbox, which is characterized by comprising: the outer side surface of the lower plug body is provided with threads for connecting a gearbox, a first ventilation cavity is arranged in the lower plug body, the upper surface of the first ventilation cavity is an inclined plane inclined inwards, and the surface of the first ventilation cavity is an ultra-oleophylic surface; the upper plug body is hermetically arranged on the lower plug body and is provided with a second vent cavity communicated with the lower plug body, and the inner surface of the second vent cavity is an ultra-oleophilic and ultra-hydrophobic surface; the oil baffle plate is arranged in the upper plug body, is positioned at the lower part of the second vent cavity, and is uniformly and densely distributed with through holes, the upper surface of the oil baffle plate and the inner surface of the through holes are both super-oleophilic and super-hydrophobic surfaces, and the lower surface of the oil baffle plate is a super-oleophilic surface; a liquid-resistant airway comprising: the plug comprises a fixed frame, a plurality of hydrophobic plates and a sealing ring, wherein the fixed frame is arranged at the upper part of the upper plug body; a third vent cavity is formed between the adjacent hydrophobic plates, the lower part of the third vent cavity is a super oleophilic and super hydrophobic surface, and the upper part of the third vent cavity is a super oleophobic and super hydrophobic surface; and the plug cover is arranged above the upper plug body through bolts, the outer edge of the plug cover extends downwards to form a cover, and a ventilation gap is formed between the plug cover and the upper plug body.

Further, the liquid blocking and air venting plug for the gearbox provided by the invention can also have the following characteristics: the inner surface and the outer surface of the plug cover are both super-hydrophobic surfaces, and the contact angle is between 165 degrees and 180 degrees.

Further, the liquid blocking and air venting plug for the gearbox provided by the invention can also have the following characteristics: the included angle between the upper surface of the lower plug body and the horizontal plane is between 2 and 30 degrees.

Further, the method for blocking liquid and ventilating the plug for the gearbox provided by the invention can also have the following characteristics: the upper plug body is fixedly connected with the lower plug body through bolts, a sealing ring is arranged at the joint, hob patterns are arranged on the outer surface of the upper plug body, the oil baffle plate is fixed in the upper plug body through the bolts, gaps are reserved between the periphery of the oil baffle plate and the inner wall of the second vent cavity, and the fixing frame is fixed on the upper portion of the upper plug body through a positioning pin.

Further, the liquid blocking and air venting plug for the gearbox provided by the invention can also have the following characteristics: the distance between the hydrophobic plates is between 0.1mm and 0.5 mm.

Further, the liquid blocking and air venting plug for the gearbox provided by the invention can also have the following characteristics: the surfaces of the upper plug body, the oil baffle plate and the water drainage plate are all prepared by femtosecond laser, the laser processing frequency is 100KHz, the laser power is 1-8W, the scanning speed is 50-1600 mm/s, and the scanning interval is 0.01-0.09 mm.

Further, the liquid blocking and air venting plug for the gearbox provided by the invention can also have the following characteristics: the second vent chamber includes: the first ventilation cavity is provided with a linear ventilation section with a rectangular cross section and an inclined ventilation section with an isosceles trapezoid cross section, wherein the linear ventilation section is positioned above the first ventilation cavity; the inclined angle of the inclined ventilation section is between 30 and 60 degrees.

Further, the liquid blocking and air venting plug for the gearbox provided by the invention can also have the following characteristics: the height ratio of the linear ventilation section to the inclined ventilation section is 1: 3.

further, the method for blocking liquid and ventilating the plug for the gearbox provided by the invention can also have the following characteristics: the diameter of the through hole on the oil baffle plate is 0.1-0.5 mm.

Further, the method for blocking liquid and ventilating the plug for the gearbox provided by the invention can also have the following characteristics: the contact angle of the super-oleophobic and super-hydrophobic surface at the upper part of the third vent cavity is between 65 and 180 degrees.

Action and Effect of the invention

According to the liquid blocking and ventilating plug for the gearbox, when the gas pressure in the gearbox is increased, oil mist airflow enters the lower plug body from the bottom and flows to the upper plug body through the oil baffle plate through hole and the peripheral ventilating gap, in the process, as the surfaces of the lower plug body and the oil baffle plate are both oleophylic structures, most of oil is condensed and attached to the surfaces of the lower plug body and the oil baffle plate, and then flows back to the gearbox for first oil-gas separation; after the oil-gas flow subjected to primary separation enters the upper plug body through the oil baffle plate, the oil-gas flow is subjected to secondary separation by the oleophilic side wall of the upper plug body, the separated oil is attached to the side wall of the upper plug body and flows back to the gearbox, and secondary oil-gas separation is completed; then the airflow continuously goes upwards to the liquid blocking air passage, and as the oleophylic effect of the liquid blocking air passage close to the inner cavity side of the plug body is in gradient arrangement, the oil gas is more oleophobic upwards, the oil gas cannot continuously rise after being condensed, at the moment, oil drops can be blocked from passing through to allow the air to escape, and the third-time isolation and filtration of the oil gas is realized; finally, gas is discharged from a ventilation gap between the plug body and the plug cover; in the above process, the oil and gas are sufficiently separated, so that oil injection can be effectively prevented. Furthermore, the plug cover is a first barrier for effectively blocking dust, impurities and water in the external environment, and air is not limited to enter and exit; because the liquid blocking air passage is hydrophobic at the side close to the plug cover, the liquid blocking air passage is a second barrier, and the air inlet and outlet are not limited; the upper plug body and the oil baffle plate are both super-hydrophobic surfaces and are third barriers, and air inlet and outlet are not limited; in the process, external impurities, particularly water, can be effectively blocked, so that water can be practically prevented from entering the gearbox.

In conclusion, the ventilation plug can ventilate and block liquid (prevent water from entering and prevent oil from leaking) in two directions, realizes four functions of ventilation, oil leakage prevention, water entering prevention and impurity prevention by multiple protection, and has the advantages of compact structure, safety, reliability and long service life; meanwhile, due to the arrangement of the super-oleophilic, super-hydrophobic and super-oleophobic surfaces in each structure, the flow can be effectively guided, and oil stain accumulation and blockage are prevented; in addition, the split structure is convenient for dismounting, replacing and cleaning parts.

Drawings

FIG. 1 is a schematic diagram of a liquid blocking vent plug for a transmission according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an oil deflector in an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a liquid blocking air passage in an embodiment of the invention;

FIG. 4 is an exploded view of a transmission dam vent plug according to an embodiment of the present invention; and

FIG. 5 is a dimensional view of a liquid blocking vent plug for a transmission in an embodiment of the present invention.

Detailed Description

The liquid blocking and air venting plug for a transmission according to the present invention will be described in detail with reference to the accompanying drawings.

< example >

As shown in fig. 1 to 5, the present embodiment provides a liquid blocking vent plug 10 for a transmission, including: the plug comprises a lower plug body 11, an upper plug body 12, an oil baffle 13, a liquid-blocking air channel 14 and a plug cover 15.

The outer surface of the lower plug body 11 is provided with threads for connecting a gearbox, and a first ventilation cavity is arranged in the lower plug body. The upper surface of the first ventilation cavity is an inclined plane which is inclined inwards, and the included angle between the upper surface of the first ventilation cavity and the horizontal plane is 6 degrees. And the inner surface and the upper surface of the first ventilation cavity are both super-oleophilic surfaces.

The upper plug body 12 is hermetically mounted on the lower plug body 11 and is provided with a second vent cavity communicated with the lower plug body 11, and the inner surface of the second vent cavity is an ultra-oleophilic and ultra-hydrophobic surface. In this embodiment, the upper plug body 12 and the lower plug body 11 are fixedly connected by a bolt, a sealing ring 12a is arranged at the joint, and a hob pattern is arranged on the outer surface of the upper plug body 12 to increase the friction force required for disassembly and assembly, so that the whole breather plug 10 can be assembled on the automobile transmission case through the thread of the lower plug body 11. As shown in fig. 1 and 5, the second vent chamber includes: the first ventilation cavity is provided with a linear ventilation section with a rectangular cross section and an inclined ventilation section with an isosceles trapezoid cross section, wherein the linear ventilation section is positioned above the first ventilation cavity; the height ratio of the linear ventilation section to the inclined ventilation section is 1: 3, the diameter of the top of the inclined ventilation section is the same as the inner diameter of the first ventilation cavity, and the diameter ratio of the top to the bottom of the inclined ventilation section is 1: 2; and the inclined angle of the inclined ventilation section is 60 degrees, so that the oil guiding effect is best.

The oil baffle plate 13 is fixed in the upper plug body 12 through bolts and fixing lugs, and a gap is reserved between the periphery of the oil baffle plate and the inner wall of the second vent cavity. In this embodiment, the oil baffle 13 is located at the top of the straight ventilation section and below the inclined ventilation section, and as shown in fig. 2, through holes are uniformly and densely distributed on the oil baffle 13, the diameter of each through hole is 0.1-0.5 mm, and the thickness of the oil baffle 13 is 2 mm. The surface of the oil baffle plate 13 is subjected to laser treatment, the upper surface and the inner surface of the through hole are both super-oleophilic and super-hydrophobic surfaces, and the lower surface of the oil baffle plate 13 is a super-oleophilic surface. The diameter of through-hole is between 0.1 ~ 0.5mm on the oil baffle 13, and centre of a circle interval and diameter ratio are 3 between the through-hole on the oil baffle 13: 1.

as shown in fig. 1 and 3, the liquid-blocking gas passage 14 includes a hydrophobic plate 14b, and a seal ring 14 c. The fixing frame 14a is fixedly attached to the upper portion of the upper plug body 12 by a positioning pin. The plurality of hydrophobic plates 14b are arranged in the fixed frame 14a in parallel, and the spacing is between 0.1mm and 0.5mm, so that a grid structure is formed; a third rectangular vent cavity is formed between the adjacent hydrophobic plates 14 b; in this embodiment, the lower portion of the hydrophobic plate 14b is an ultra-oleophilic and ultra-hydrophobic surface, the upper portion is an ultra-oleophobic and ultra-hydrophobic surface, the contact angle is between 65 ° and 180 °, and the minimum roll angle is 6 °; correspondingly, the lower part of the third vent cavity is an ultra-oleophilic and ultra-hydrophobic surface, and the upper part of the third vent cavity is an ultra-oleophobic and ultra-hydrophobic surface. The seal ring 14c is located between the fixed frame 14a and the upper plug body 12.

The plug cover 15 is mounted above the upper plug body 12 through bolts, the outer edge of the plug cover 15 extends downwards to form a cover, and a ventilation gap is formed between the cover and the upper plug body 12. In this embodiment, the inner and outer surfaces of the plug cover 15 are both super-hydrophobic surfaces, and the contact angle is between 165 ° and 180 °.

The super-hydrophobic and super-oleophylic surfaces of the upper plug body 12, the oil baffle plate 13 and the hydrophobic plate 14b are all prepared by femtosecond laser, the laser processing frequency is 100KHz, the laser power is 1-8W, the scanning speed is 50-1600 mm/s, and the scanning interval is 0.01-0.09 mm. The optimal parameters are as follows: the frequency is 100KHz, the power is 3W, the scanning speed is 50mm/s, the scanning interval is 0.01, the surface contact angle is 168 degrees, the rolling angle is 2 degrees, and the surface oleophylic effect is the best.

The above is a specific structure of the liquid blocking and venting plug 10 for the transmission provided in the present embodiment, and based on the above structure, a specific using method and an operation process of the liquid blocking and venting plug 10 for the transmission are as follows:

the installer holds the hob pattern on the outer surface of the upper plug body 12 with a hand and then rotates it so that the threads of the lower plug body 11 are screwed into the connection gearbox.

When the gas pressure increases in the gearbox, the oil mist airflow enters the lower plug body 11 from the bottom, flows to the upper plug body 12 through the through hole of the oil baffle plate 13 and the peripheral ventilation gap, and in the process, most of oil is condensed and attached to the lower plug body 11 and the oil baffle plate 13 due to the fact that the surfaces of the oil baffle plate and the lower plug body are oleophylic structures and then flows back to the gearbox to perform first oil-gas separation.

After the oil-gas flow subjected to primary separation enters the upper plug body 12 through the through hole of the oil baffle plate 13, the oil-gas flow is subjected to secondary separation by the side wall of the upper plug body 12 which is oleophylic, and the separated oil is attached to the side wall of the upper plug body 12 and flows back to the gearbox, so that secondary oil-gas separation is completed.

Then, the air current continues to go up to hinder liquid air flue 14, because hinders liquid air flue 14 lower part oleophilic, and the upper portion is oleophobic, consequently can't continue to rise after the oil gas condenses, and then can block oil droplet and let the air escape, realizes that the oil gas is kept apart the filtration for the third time.

Finally, after the air subjected to third isolation filtering overflows from the upper part of the liquid blocking air passage 14, the air enters a ventilation gap between the plug body and the plug cover 15 and is discharged.

On the contrary, for external impurities, water and the like, the plug cover 15 is a first barrier for effectively blocking dust, impurities and water in the external environment, and air is not limited to enter and exit. When the humidity outside the gearbox is high, water mist exists or the surface of the plug cover 15 is wetted by water, the surface of the plug cover is a super-hydrophobic surface, so that liquid drops can be guided to flow away along the outer surface, and the liquid drops are prevented from entering the inside. Even if a small amount of moisture enters the plug cover 15 under special conditions, the liquid blocking air passage 14 is hydrophobic on the side close to the plug cover 15, so that the moisture can be prevented from entering, the water blocking air passage is a second water blocking barrier, and meanwhile, the air is not limited to enter and exit; further, in an extreme case, if a part of moisture still enters the upper plug body 12 through the liquid blocking air passage 14, the upper plug body 12 and the oil baffle plate 13 are both super-hydrophobic surfaces, so that the moisture can be effectively prevented from further passing through, and the air inlet and the air outlet are not limited; through the three barriers, water can be practically blocked, water is effectively prevented from entering the gearbox, and safe and stable operation of the gearbox is guaranteed.

The above embodiments are merely illustrative of the technical solutions of the present invention. The liquid blocking and air venting plug for a transmission according to the present invention is not limited to the above embodiments, but is defined by the scope of the appended claims. Any modification or supplement or equivalent replacement made by a person skilled in the art on the basis of this embodiment is within the scope of the invention as claimed in the claims.

Claims

1. A hydraulic-blocking breather plug for a transmission, comprising:

the outer side surface of the lower plug body is provided with threads for connecting a gearbox, a first ventilation cavity is arranged in the lower plug body, the upper surface of the first ventilation cavity is an inclined plane inclined inwards, and the surface of the first ventilation cavity is a super-oleophylic surface;

the upper plug body is hermetically arranged on the lower plug body and is provided with a second vent cavity communicated with the lower plug body, and the inner surface of the second vent cavity is an ultra-oleophilic and ultra-hydrophobic surface;

the oil baffle plate is arranged in the upper plug body, is positioned at the lower part of the second vent cavity and is densely provided with through holes, the upper surface of the oil baffle plate and the inner surface of each through hole are both super-oleophilic and super-hydrophobic surfaces, and the lower surface of the oil baffle plate is a super-oleophilic surface;

a liquid-resistant airway comprising: the upper plug body is provided with a fixing frame, a plurality of hydrophobic plates and a sealing ring, wherein the fixing frame is arranged at the upper part of the upper plug body; a third vent cavity is formed between the adjacent hydrophobic plates, the lower part of the third vent cavity is a super oleophilic and super hydrophobic surface, and the upper part of the third vent cavity is a super oleophobic and super hydrophobic surface; and

the plug cover is installed above the upper plug body through bolts, the outer edge of the plug cover extends downwards to form a cover, and a ventilation gap is formed between the plug cover and the upper plug body.

2. The liquid blocking vent plug for a transmission according to claim 1, wherein:

wherein the inner surface and the outer surface of the plug cover are both super-hydrophobic surfaces, and the contact angle is between 165 degrees and 180 degrees.

3. The liquid blocking vent plug for a transmission according to claim 1, wherein:

wherein, the included angle between the upper surface of the lower plug body and the horizontal plane is between 2 degrees and 30 degrees.

4. The liquid blocking vent plug for a transmission according to claim 1, wherein:

wherein the upper plug body and the lower plug body are fixedly connected through bolts, a sealing ring is arranged at the joint, the outer surface of the upper plug body is provided with hob patterns,

the oil baffle plate is fixed in the upper plug body through bolts, and gaps are reserved between the periphery of the oil baffle plate and the inner wall of the second vent cavity,

the fixing frame is fixed on the upper part of the upper plug body through a positioning pin.

5. The liquid blocking vent plug for a transmission according to claim 1, wherein:

wherein the distance between the hydrophobic plates is between 0.1mm and 0.5 mm.

6. The liquid blocking vent plug for a transmission according to claim 1, wherein:

the surfaces of the upper plug body, the oil baffle plate and the hydrophobic plate are all prepared by femtosecond laser, the laser processing frequency is 100KHz, the laser power is 1-8W, the scanning speed is 50-1600 mm/s, and the scanning distance is 0.01-0.09 mm.

7. The liquid blocking vent plug for a transmission according to claim 1, wherein:

wherein the second vent chamber includes: the first ventilation cavity is provided with a linear ventilation section with a rectangular cross section and an inclined ventilation section with an isosceles trapezoid cross section, wherein the linear ventilation section is positioned above the first ventilation cavity; the inclined angle of the inclined ventilation section is between 30 and 60 degrees.

8. The liquid blocking vent plug for a transmission according to claim 7, wherein:

wherein the height ratio of the linear ventilation section to the inclined ventilation section is 1: 3.

9. the liquid blocking vent plug for a transmission according to claim 1, wherein:

the diameter of the through hole in the oil baffle plate is 0.1-0.5 mm.

10. The liquid blocking vent plug for a transmission according to claim 1, wherein:

wherein the contact angle of the super-oleophobic and super-hydrophobic surface at the upper part of the third vent cavity is between 65 and 180 degrees.