A micro-pressure ventilation method and device for a transmission to achieve micro-pressure dustproof, pressurized and waterproof

Abstract

The present invention discloses a micro-pressure ventilation method and device for realizing micro-pressure dustproof, pressurized and waterproof of a transmission, comprising a vent pipe, the top of which is provided with a vent; further comprising a plug body, a pressurizing lever and a buoyancy component; the plug body blocks the vent of the vent pipe and is used for dustproof under normal working conditions; the pressurizing lever is located between the buoyancy component and the plug body, and after the transmission enters the water, the pressurizing lever converts the buoyancy of the buoyancy component in the water into multiple pressures applied to the plug body, forcing the plug body to more tightly block the vent to prevent water from entering the transmission housing. The advantage is that the transmission housing can basically maintain normal pressure, and when the air pressure in the housing is slightly increased, the air can be exhausted to the outside, so that the exhaust airflow is gentle, and the exhaust volume per unit time is significantly reduced compared with the existing ventilation device. It can avoid the direct discharge of gas that has no time to separate oil and gas in the oil-gas separation labyrinth when the pressure is too high and suddenly erupts, and avoid the accumulated oil in the ventilation pipeline being flushed out by the high-pressure airflow.

Description

Technical Field

[0001] The invention relates to a ventilation device for an automobile transmission, and in particular to a micro-pressure ventilation method and device for a transmission to realize micro-pressure dustproof, pressurized and waterproof, and belongs to the technical field of speed change equipment. Background Art

[0002] The housing of the car's transmission is a closed cavity with various gear linkage structures in it. There is also a certain depth of lubricating oil in the lower part of the cavity for lubricating the gear teeth and axles. The lubricating oil in the lower part of the cavity splashes onto the gear teeth and axles in the upper space under the centrifugal force generated by the rotation of the gears, and lubricates the gear teeth and axles in the upper part of the cavity. But at the same time, a small part of the splashed lubricating oil will also mix into the air in the upper cavity in the form of oil foam and oil vapor. When the heat generated by the transmission during operation causes the temperature in the transmission cavity to rise, the oil-containing gas in the cavity will be ejected outward from a device called a vent valve set on the top shell of the transmission cavity. If the oil and gas separation process is not performed, the gas ejected from the transmission cavity at high temperature will entrain a large amount of oil mixed in the gas, resulting in what is known as vent valve oil leakage in the industry. In order to reduce the oil content of the gas ejected from the vent valve, the prior art is to set an oil-gas separation labyrinth in the transmission cavity below the vent hole of the vent valve, so that the gas ejected outward at high temperature passes through the oil-gas separation labyrinth for oil-gas separation and then ejected outward through the vent valve. However, the oil-gas separation effect of the oil-gas separation labyrinth has always been unsatisfactory. The reason is that the existing vent valve is a normally closed plug cover, and for the purpose of dust and water prevention, the weight of the vent valve plug cover is large, and the opening pressure is large, resulting in a high air pressure in the cavity. When the pressure increases to a certain value, the plug cover will be suddenly opened, and the oil and gas will suddenly be ejected in large quantities along the exhaust pipe at one time, so that the oil in the oil and gas passing through the separation labyrinth is ejected before it has time to condense and settle, and the grease in the pipeline is also rushed out, thereby causing the vent valve to leak oil. Summary of the invention

[0003] The main technical problem to be solved by the present invention is that the oil leakage and oil seepage caused by the sudden jet of the normally closed heavy pressure vent valve is that the oil and gas in the jetted gas are not completely separated and the accumulated oil in the pipeline is flushed out. At the same time, it is necessary to ensure that the device has a reliable dustproof function under normal working conditions and a reliable waterproof function when and after the transmission enters water.

[0004] In view of the above problems, the technical solution proposed by the present invention is:

[0005] A micro-pressure ventilation method for a transmission to achieve micro-pressure dustproof, pressurized and waterproof is provided, wherein a plug body invention is placed at the pipe mouth of a vent pipe, and a pressurizing component and a buoyancy component are provided; under normal working conditions, the plug body invention only presses and blocks the pipe mouth of the vent pipe with its own weight to prevent dust from entering the transmission housing invention, and when the air pressure in the housing invention increases, the plug body invention can be pushed to exhaust air outward; when the transmission enters water, the buoyancy of the water on the buoyancy component is converted into pressure on the plug body invention through the pressurizing component, so that the plug body invention and the pipe mouth of the vent pipe are sealed to prevent water from entering the transmission housing invention.

[0006] Furthermore, the above-mentioned transmission realizes a micro-pressure ventilation method for micro-pressure dustproof, boosted pressure and waterproofing, which is to set the boost component as a boost lever, so that the length of its power arm is more than 3 times the length of the resistance arm, so that the resistance arm is located above the plug body invention and a gap is left between the resistance arm and the plug body invention; the buoyancy component is set at a position capable of supporting the end of the power arm of the boost lever from the bottom; when the transmission enters the water, the buoyancy component is subjected to the buoyancy of the water to support the end of the power arm of the boost lever upward, forcing the boost lever to rotate around the support axis of the support; thereby the resistance arm applies downward pressure to the plug body.

[0007] A transmission designed according to the above method realizes a micro-pressure ventilation device for micro-pressure dustproof, pressurized and waterproof, including a vent pipe invention, the top of the vent pipe invention has a vent port invention, and is characterized in that: it also includes a boosting mechanism, the boosting mechanism includes a plug body invention, a boosting lever and a buoyancy component; the plug body invention blocks the vent port invention of the vent pipe invention, and is used for dust prevention under normal working conditions; the boosting lever is located between the buoyancy component and the plug body invention, and after the transmission enters the water, the buoyancy of the buoyancy component in the water is converted into multiple pressures by the boosting lever and applied to the plug body invention, forcing the plug body invention to more tightly block the vent port invention to prevent water from entering the housing invention of the transmission.

[0008] Furthermore, the outer periphery of the plug body invention has a pressing edge invention that is unfolded in a skirt shape, and the pressing edge invention is always in contact with the outer peripheral surface of the vent invention.

[0009] Furthermore, the top edges of the vent pipe invention on the left and right sides of the vent invention are symmetrically arranged with a support one invention and a support two invention; the booster lever is divided into a booster lever one invention symmetrically installed on the support one invention and a booster lever two invention installed on the support two invention, the power arm and the resistance arm of the booster lever one invention are respectively a buoyancy arm one invention and a booster arm one invention, the power arm and the resistance arm of the booster lever two invention are respectively a buoyancy arm two invention and a booster arm two invention, the booster arm one invention is located above the left side of the plug body invention and has a gap with the plug body invention, and the booster arm two invention is located above the right side of the plug body invention and has a gap with the plug body invention.

[0010] Furthermore, the buoyancy component is a float invention with an annular closed cavity, and a sleeve hole invention is provided in the center of the float invention which is communicated with each other up and down. The float invention is sleeved on the vent pipe invention through the sleeve hole invention and can slide up and down on the vent pipe invention. The upper left and right sides of the float invention can form a force interaction with the outer ends of the buoyancy arm one invention and the outer ends of the buoyancy arm two invention respectively. When the float invention floats up due to the buoyancy of water, it can push the buoyancy arm one invention and the buoyancy arm two invention upward at the same time.

[0011] Furthermore, the top end surface of the float invention is a conical surface that enables oil to flow downward, and correspondingly, the outer periphery of the vent pipe invention around the vent invention is provided with a radially outward conical oil guide eaves invention.

[0012] Furthermore, it also includes an outer cover invention for preventing dust from the boosting mechanism and waterproofing the boosting mechanism in linkage with the boosting mechanism, the outer cover invention has a cylindrical inner hollow space, the bottom end of which is open, and the outer periphery and the upper part are sealed; the outer cover invention is buckled on the outside of the boosting mechanism, and the bottom periphery thereof is fitted with the transmission case invention, and the boosting mechanism is enclosed in the outer cover invention and there is a gap between the outer cover invention and the inner wall.

[0013] Furthermore, on both sides of the limit stop invention on the outer periphery of the lower part of the ventilation pipe invention, there are horizontally arranged through rod holes inventions that are connected at both ends, and the through rod holes invention is sleeved with a limit rod invention with both ends protruding for limiting the outer cover invention; correspondingly, the inner wall of the bottom end port of the outer cover invention is provided with a spiral annular wall limit platform invention, and the two ends of the limit rod invention are pressed on the annular wall limit platform invention; the two ends of the limit rod invention each have a section of spiral structure invention that gives the limit rod invention elasticity.

[0014] Furthermore, the annular wall limit platform invention is divided into an inclined section invention and a horizontal section invention; the terminal end of the inclined section invention is connected to the starting end of the horizontal section invention, and there is a spacing notch invention between the starting end and the terminal end of the horizontal section invention for the limit rod invention to be screwed into.

[0015] The advantages of the present invention are:

[0016] 1. This device adopts special micro-pressure dust-proof, pressurized and waterproof measures, so that under normal working conditions, the plug of this ventilation mechanism is always in a micro-pressure dust-proof state with extremely low pressure, and the housing cavity of the transmission can basically maintain normal pressure. When the temperature rises and the air pressure in the cavity increases slightly, the air can be exhausted to the outside, so that the exhaust airflow is gentle, and the amount of air exhausted per unit time is significantly reduced compared with the existing ventilation device. It can avoid the sudden eruption of a large amount of oil and gas under high pressure, so that the gas that does not have time to separate oil and gas in the oil and gas separation maze is directly discharged, and avoid the accumulated oil in the ventilation pipeline being flushed out by the high-pressure airflow.

[0017] 2. This device uses two-stage dust and water resistance, which can maintain a near-normal pressure in the shell cavity and has reliable dust and water resistance. This is mainly reflected in the first-level micro-pressure dust resistance of the outer cover and the second-level micro-pressure dust resistance of the plug body; the outer cover and the plug body are linked to waterproof by pressurization, and the plug body is waterproof by pressurization alone. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional schematic diagram of a boost mechanism for a transmission micro-pressure ventilation device;

[0019] Figure 2 for Figure 1 A partial schematic diagram of

[0020] Figure 3 is a three-dimensional schematic diagram of a ventilating pipe;

[0021] Figure 4 is a three-dimensional schematic diagram of the plug body;

[0022] Figure 5 is a cross-sectional schematic diagram of the supercharging mechanism;

[0023] Figure 6 is a cross-sectional schematic diagram of the micro-pressure ventilation device;

[0024] Figure 7 is a three-dimensional schematic diagram of the outer cover;

[0025] Figure 8 It is a three-dimensional schematic diagram of the ring wall limit platform;

[0026] Fig. 9 It is a three-dimensional schematic diagram of the limit rod.

[0027] In the figure: 100, shell; 1, ventilation pipe; 11, ventilation port; 12, limit stop; 13, through rod hole; 2, plug body; 21, pressing edge; 3, booster lever one; 31, support one; 32, buoyancy arm one; 33, booster arm one; 4, booster lever two; 41, support two; 42, buoyancy arm two; 43, booster arm two; 5, side column one; 51, notch one; 6, side column two; 61, notch two; 7, buoy; 71, sleeve hole; 72, oil guide eaves; 8, outer cover; 81, ring wall limit platform; 811, inclined section; 812, horizontal section; 813, interval notch; 9, limit rod; 91, spiral structure. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with embodiments and drawings:

[0029] like Figure 1 , 2As shown in , 5, a micro-pressure ventilation method for a transmission to achieve micro-pressure dustproof, pressurized and waterproof is to place a plug body 2 at the pipe mouth of the ventilation pipe, and set a boosting component and a buoyancy component; under normal working conditions, the plug body 2 only presses and blocks the pipe mouth of the ventilation pipe with its own weight to prevent dust from entering the transmission case 100. When the air pressure in the case 100 increases, it can push the plug body 2 to exhaust air outward; when the transmission enters water, the buoyancy of the water on the buoyancy component is converted into pressure on the plug body 2 through the boosting component, so that the plug body 2 and the pipe mouth of the ventilation pipe are sealed to prevent water from entering the transmission case 100. The guiding ideology of this method is to consider dust prevention and waterproofing separately; for dust prevention under normal working conditions, there is no need to press the plug body against the vent 11 of the vent pipe with a large pressure, but only the plug body needs to block the vent 11 with a very small pressure to achieve the dust prevention effect, so that when the air pressure in the transmission case 100 increases slightly, the plug body can be pushed to exhaust and release pressure, thereby achieving micro-pressure ventilation and avoiding a large amount of oil and gas eruption causing oil loss in the transmission; when the transmission enters water, it is automatically pressurized to prevent water, and the buoyancy of the water is converted into pressure on the plug body.

[0030] Furthermore, the boosting component is configured as a boosting lever, so that the length of its power arm is more than 3 times the length of the resistance arm, so that the resistance arm is located above the plug body 2 and a gap is left between the resistance arm and the plug body 2; the buoyancy component is configured in a position capable of supporting the end of the power arm of the boosting lever from the bottom thereof; when the transmission enters the water, the buoyancy component is subjected to the buoyancy of the water to support the end of the power arm of the boosting lever upward, forcing the boosting lever to rotate around the support shaft of the support; thereby, the resistance arm applies downward pressure to the plug body 2.

[0031] The following is a micro-pressure ventilation device designed according to the above method for a transmission to achieve micro-pressure dustproof, pressurized and waterproof.

[0032] like Figure 1 , 5As shown, the micro-pressure venting device includes a vent pipe 1, the top of which has a vent 11, and also includes a boost mechanism, a plug body 2, a boost lever and a buoyancy component; the plug body 2 blocks the vent 11 of the vent pipe 1, and is used to prevent dust under normal working conditions; the boost lever is located between the buoyancy component and the plug body 2, and after the transmission enters the water, the buoyancy of the buoyancy component in the water is converted into multiple pressures by the boost lever and applied to the plug body 2, forcing the plug body 2 to block the vent 11 more tightly to prevent water from entering the housing 100 of the transmission. The plug body 2 in the above-mentioned setting is small in size, low in material density, and light in weight. In general, it only relies on its own weight to block the vent 11 of the vent pipe, and it can also be blocked by a very low-strength spring applying a small pressure to block the vent 11 of the vent pipe, and its purpose is only to prevent dust in the external air from entering the vent pipe. Under normal working conditions, the air pressure that can be formed in the transmission housing 100 is very small. Since the plug body 2 is only pressed against the vent 11 with a very small force, when the air pressure formed in the transmission housing 100 increases slightly, the plug body 2 can be pushed upward to release the air and pressure outward. In this way, the discharged airflow is gentle, and the amount of air discharged per unit time is significantly reduced compared with the existing ventilation device, which can avoid the sudden eruption of a large amount of oil and gas under high pressure, so that the gas that does not have time to separate oil and gas in the oil and gas separation maze is directly discharged, and the accumulated oil in the ventilation pipeline is prevented from being flushed out by the high-pressure airflow. At the same time, in addition to ensuring dust prevention under normal working conditions, it can also ensure that when and after the gearbox enters water, this mechanism can tightly seal the vent hole to prevent water from entering the cavity of the transmission housing 100.

[0033] It can be seen from the above structure and the technical effects produced by the structure that the micro-pressure ventilation mechanism refers to that the plug body 2 is light in weight and only relies on its own weight or a very low-strength spring to apply a small pressure to the plug body to block the vent 11; secondly, it refers to that the air pressure that can be formed in the transmission case 100 under normal working conditions is very small, and as long as the air pressure formed in the transmission case 100 increases slightly, the plug body 2 can be pushed upward to exhaust and release pressure to the outside.

[0034] Here are further improvements.

[0035] like Figure 1 , 3 As shown in FIG. 4 , the shape of the vent 11 of the vent pipe 1 corresponds to the shape of the contact surface of the plug body 2, and the lower part of the plug body 2 is located in the vent 11. In this way, the vent 11 and the contact surface of the plug body 2 can be better fitted without much pressure.

[0036] The plug body 2 is a spherical plug body 2 with elasticity, and the vent of the vent pipe 1 is a spherical concave opening that matches the lower surface of the spherical plug body 2, and the lower part of the spherical plug body 2 is located in the spherical concave opening. The spherical plug body 2 matches the spherical concave opening well and is also easy to process. However, the plug body 2 can also have a variety of shapes, such as a cone, and the inner conical surface of the vent that matches it is also very close, and it is also relatively easy to process.

[0037] The outer periphery of the plug body 2 has an elastic pressing edge 21 that is spread out in a skirt shape, and the pressing edge 21 always fits with the outer peripheral surface of the vent 11. The pressing edge 21 has two main functions: 1. When the plug body 2 has a slight jump due to mechanical vibration and road bumps (there will not be a big jump, and there are necessary limiting measures, which will be described later), the elastic pressing edge 21 can always fit with the outer peripheral surface of the vent 11, thereby achieving a better dustproof effect. 2. Airflow guidance, try to avoid the gas in the transmission spraying upward onto the lever support, so that the support shaft is stained with oil.

[0038] like Figure 1 , 2 As shown in 3, 5, the top edge of the vent pipe 1 on the left and right sides of the vent 11 has a symmetrically arranged support 1 31 and a support 2 41; the booster lever is divided into a booster lever 1 3 symmetrically installed on the support 1 31 and a booster lever 2 4 installed on the support 2 41, and the booster lever 1 3 and the booster lever 2 4 are both installed on the support 1 31 and the support 2 41 through a support shaft, and the power arm and resistance arm of the booster lever 1 3 are respectively a buoyancy arm 1 32 and a booster arm 1 33, and the power arm and resistance arm of the booster lever 2 4 are respectively a buoyancy arm 2 42 and a booster arm 2 43, and the booster arm 1 33 is located above the left side of the plug body 2 and has a gap with the plug body 2, and the booster arm 2 43 is located above the right side of the plug body 2 and has a gap with the plug body 2. This arrangement is to use the upward buoyancy generated by water to convert it into a downward pressure on the plug body 2 through a lever. The booster arm 33 is located above the left side of the plug body 2 and has a gap with the plug body 2. The gap is very small, less than 1 mm, and its purpose is to limit the jumping height of the plug body 2 when it vibrates to achieve an ideal dust-proof effect.

[0039] The length of the buoyancy arm 1 32 of the boosting lever 1 3 is more than three times the length of the boosting arm 1 33; the length of the buoyancy arm 2 42 of the boosting lever 2 4 is more than three times the length of the boosting arm 2 43. Since the force to be utilized by the boosting lever is buoyancy, this arrangement is to convert a small buoyancy into a large pressure. In actual application, the length of the buoyancy arm will be more than six times the length of the boosting arm.

[0040] The buoyancy component is a float 7 with an annular closed cavity, and a sleeve hole 71 is provided in the center of the float 7, and the float 7 is sleeved on the vent pipe 1 through the sleeve hole 71 and can slide up and down the vent pipe 1, and the upper left and right sides of the float 7 can form a force interaction with the outer ends of the buoyancy arm 1 32 and the outer ends of the buoyancy arm 2 42, respectively. When the float 7 floats up due to the buoyancy of the water, it can push the buoyancy arm 1 32 and the buoyancy arm 2 42 upward at the same time. The material of the float 7 is generally selected from plastic materials with a lower density, so as to reduce its own weight and obtain a larger buoyancy.

[0041] On both sides of the upper end of the buoy 7, there are side columns 1 5 and 2 6 respectively. The upper ends of the side columns 1 5 and 2 6 are respectively provided with radial notches 1 51 and 2 61 relative to the buoy 7; the outer end of the buoyancy arm 1 32 of the booster lever 1 is located in the radial notch 1 51 of the side column 1 5 and can slide radially in the notch 1 51; the outer end of the buoyancy arm 2 42 of the booster lever 2 is located in the radial notch 2 61 of the side column 2 6 and can slide radially in the notch 2 61.

[0042] The top surface of the float 7 is a conical surface that allows the oil to flow downward, and correspondingly, the outer periphery of the vent pipe 1 around the vent 11 is provided with a radially outward conical oil guide edge 72. The purpose of this arrangement is to guide the oil that may overflow from the vent to the outer periphery of the float 7 through the conical oil guide edge 72 and then flow downward to the transmission housing 100, so as to prevent the oil from flowing into the sleeve hole 71 in the center of the float 7 and affecting the up and down sliding of the float 7.

[0043] A limit stopper 12 is also provided on the ventilation pipe below the buoy 7 to limit the downward sliding of the buoy 7 .

[0044] like Figure 6 , 7As shown, the micro-pressure ventilation device for realizing micro-pressure dustproof, pressurized and waterproof of the transmission also includes an outer cover 8 for dustproofing the supercharging mechanism and waterproofing in linkage with the supercharging mechanism. The outer cover 8 has a cylindrical inner hollow space, the bottom end of which is open, and the outer periphery and the upper part are sealed; the outer cover 8 is buckled outside the supercharging mechanism, and its bottom periphery is in contact with the transmission housing 100. The supercharging mechanism is enclosed in the outer cover 8 and there is a gap between the inner wall of the outer cover 8. The bottom periphery of the outer cover 8 is in contact with the transmission housing 100, but it is not in contact under heavy pressure. Under normal working conditions, micro-pressure dustproofing is realized. At the same time, it is ensured that when the air pressure in the outer cover 8 is slightly increased, the gas in the outer cover 8 can push the outer cover 8 to discharge outward. Since the bottom periphery of the outer cover 8 is in contact with the transmission housing 100 under micro-pressure, when the transmission enters the water, the outer cover 8 will float upward due to the buoyancy of the water. However, the height of the outer cover 8 floating upward will also be strictly limited to a very small range. If the floating height is lower than 1mm, water will enter the outer cover 8 from the gap between the bottom periphery of the outer cover 8 and the transmission housing 100. When the transmission does not overturn with the vehicle body, the water entering the outer cover 8 will cause the float 7 to float, and the buoyancy of the float 7 is converted into pressure on the plug body 2 through the booster lever, so that the plug body 2 tightly seals the vent 11. After the vent 11 is tightly sealed, the gas in the upper part of the outer cover 8 cannot be discharged in any direction, which will form pressure on the water surface entering the lower part of the outer cover 8, preventing water from continuing to enter the outer cover 8, thereby forming a waterless space in the upper part of the vent 11, and the vent 11 of the vent pipe is in place with this waterless space, thereby achieving a waterproof effect. Even if the water level in the outer cover 8 continues to rise and submerges the vent 11, it cannot enter the vent pipe because the continuously rising water level will generate greater buoyancy on the float 7, and the plug body 2 will obtain greater pressure through the booster lever, making the plug body 2 seal the vent 11 more tightly.

[0045] like Figure 3 , 6 As shown in Figures 8 and 9, on both sides of the limit stopper 12 at the outer periphery of the lower part of the ventilating pipe 1, there are horizontally arranged through rod holes 13 with two ends communicating with each other, and the through rod holes 13 are sleeved with a limit rod 9 with two ends protruding for limiting the outer cover 8; correspondingly, the inner wall of the bottom end of the outer cover 8 is provided with a spiral ring wall limit platform 81, and the two ends of the limit rod 9 are pressed on the ring wall limit platform 81. Obviously, the limit rod 9 is used to limit the outer cover 8 from jumping upward and limiting the height of its upward floating after entering the water.

[0046] The annular wall limiting platform 81 is divided into an inclined surface section 811 and a horizontal section 812; the terminal end of the inclined surface section 811 is connected to the beginning of the horizontal section 812, and there is a spacing gap 813 between the beginning and the terminal end of the horizontal section 812 for the limiting rod 9 to be screwed in. This arrangement is convenient for the installation of the outer cover 8 in the future. During installation, the outer cover 8 only needs to be rotated in one direction, and the end of the limiting rod 9 can enter the inclined surface section 811 of the annular wall limiting platform 81 and rise along the inclined surface section 811, and enter the horizontal section 812 through the spacing gap 813 of the annular wall limiting platform 81. After the ends of the two limiting rods 9 enter the horizontal section 812 of the annular wall limiting platform 81, the installation of the outer cover is completed.

[0047] Both ends of the limit rod 9 have a spiral structure 91 that gives the limit rod 9 elasticity. This arrangement allows the limit rod 9 to apply a flexible pressure to the outer cover, which is beneficial to preventing the outer cover 8 from vibrating. It should be noted that when the bottom periphery of the outer cover 8 is in contact with the transmission housing 100, the flexible pressure applied by the limit rod 9 to the outer cover is very small. Only when the bottom periphery of the outer cover 8 is separated from the transmission housing 100 by about 0.5 mm, the applied flexible pressure will suddenly increase.

[0048] Obviously, the above embodiments are only used to more clearly describe the present invention, and cannot be regarded as limiting the protection scope of the present invention. Any modifications in equivalent forms should be regarded as falling within the protection scope of the present invention.

Claims

1. A micro-pressure ventilation device for a transmission to achieve micro-pressure dustproof, pressurized and waterproof, comprising a ventilation pipe (1), the top end of the ventilation pipe (1) having a ventilation port (11), characterized in that: The invention also comprises a pressure-boosting mechanism, the pressure-boosting mechanism comprising a plug body (2), a pressure-boosting lever and a buoyancy component; the plug body (2) blocks the vent (11) of the vent pipe (1) and is used to prevent dust under normal working conditions; the pressure-boosting lever is located between the buoyancy component and the plug body (2); after the transmission enters the water, the buoyancy of the buoyancy component in the water is converted into a multiple pressure by the pressure-boosting lever and applied to the plug body (2), forcing the plug body (2) to more tightly block the vent (11) to prevent water from entering the housing (100) of the transmission; the top edges of the vent pipe (1) on the left and right sides of the vent (11) are provided with a symmetrically arranged support 1 (31) and a support 2 (41); The booster lever is divided into a booster lever 1 (3) symmetrically mounted on a support 1 (31) and a booster lever 2 (4) mounted on a support 2 (41); the power arm and the resistance arm of the booster lever 1 (3) are respectively a buoyancy arm 1 (32) and a booster arm 1 (33); the power arm and the resistance arm of the booster lever 2 (4) are respectively a buoyancy arm 2 (42) and a booster arm 2 (43); the booster arm 1 (33) is located above the left side of the plug body (2) and has a gap with the plug body (2); the booster arm 2 (43) is located above the right side of the plug body (2) and has a gap with the plug body (2); the buoyancy component is a buoy (7) having an annular closed cavity, and the center of the buoy (7) has upper and lower buoyant arms. The buoy (7) is sleeved on the vent pipe (1) through the sleeve hole (71) and can slide up and down on the vent pipe (1). The upper left and right sides of the buoy (7) can form a force interaction with the outer ends of the first buoyancy arm (32) and the second buoyancy arm (42). When the buoy (7) floats up due to the buoyancy of the water, it can push the first buoyancy arm (32) and the second buoyancy arm (42) upward at the same time. The buoy (7) also includes an outer cover (8) for preventing dust from the boosting mechanism and for waterproofing in conjunction with the boosting mechanism. The outer cover (8) has a cylindrical inner hollow space, the bottom end of which is open, and the outer periphery and the upper part are sealed. The outer cover (8) is buckled outside the boosting mechanism. The periphery of the bottom is fitted with the transmission housing (100), and the supercharging mechanism is enclosed in the outer cover (8) and has a gap with the inner wall of the outer cover (8); on both sides of the limit stopper (12) at the outer periphery of the lower part of the vent pipe (1), there are horizontally arranged through rod holes (13) with two ends communicating with each other, and a limit rod (9) with two ends protruding from the through rod hole (13) is sleeved in the through rod hole (13) for limiting the outer cover (8); correspondingly, a spiral ring wall limit platform (81) is provided on the inner wall of the bottom end port of the outer cover (8), and the two ends of the limit rod (9) are pressed on the ring wall limit platform (81); and the two ends of the limit rod (9) each have a section of spiral structure (91) for giving the limit rod (9) elasticity.

2. The transmission micro-pressure ventilation device for realizing micro-pressure dustproof, pressurized and waterproof according to claim 1, characterized in that: The plug body (2) has a skirt-shaped pressing edge (21) on its outer periphery, and the pressing edge (21) is always in contact with the outer periphery of the vent (11).

3. The micro-pressure ventilation device for a transmission that realizes micro-pressure dustproof, pressurized and waterproofing according to claim 1, characterized in that: The top end surface of the float (7) is a conical surface that enables oil to flow downwards. Correspondingly, the outer periphery of the vent pipe (1) around the vent opening (11) is provided with a conical oil guide edge (72) that is radially outward.

4. The micro-pressure ventilation device for a transmission that realizes micro-pressure dustproof, pressurized and waterproofing according to claim 1, characterized in that: The annular wall limiting platform (81) is divided into an inclined surface section (811) and a horizontal section (812); the terminal end of the inclined surface section (811) is connected to the beginning end of the horizontal section (812), and a spacing notch (813) is provided between the beginning and the terminal end of the horizontal section (812) for the limiting rod (9) to be screwed into.

Images