CN221800715U

CN221800715U - Water-blocking exhaust valve suitable for positive and negative pressure working conditions

Info

Publication number: CN221800715U
Application number: CN202321861994.7U
Authority: CN
Inventors: 曹继强
Original assignee: Individual
Current assignee: Individual
Priority date: 2023-07-14
Filing date: 2023-07-14
Publication date: 2024-10-01
Anticipated expiration: 2033-07-14

Abstract

The utility model discloses a water-blocking exhaust valve suitable for positive and negative pressure working conditions, which relates to the technical field of valves and comprises a main tank body, wherein the bottom of the main tank body is provided with a water inlet, a main valve body is fixedly arranged in the main tank body, the upper part of the main valve body is provided with a check ball, the check ball is solid spherical and is made of polytetrafluoroethylene, and the lower part of the main valve body is movably provided with a blocking piston; when the utility model is arranged at the top end of the water pump, when the upper part of the main tank body is connected with a negative pressure pipeline or the water level is higher than the water level of the water pump and is at positive pressure, the air at the top end of the water pump is discharged, so that the water pump can be directly started, the air accumulated at the top end of the water pump can be discharged when the water pump runs for a long time, the surge of the water pump is reduced, the safe running of the water pump is ensured, and when the utility model is arranged on the crossing siphon of a highway river of a municipal long-distance pressure water delivery pipe network, the air accumulated at the top end of the crossing siphon can be continuously discharged, so that the water delivery pipe network recovers the water delivery quantity, the water delivery efficiency is improved, and the safe running is ensured.

Description

Water-blocking exhaust valve suitable for positive and negative pressure working conditions

Technical Field

The utility model relates to the technical field of valves, in particular to a water-blocking exhaust valve suitable for positive and negative pressure working conditions.

Background

The water-blocking exhaust valve is applied to pipelines such as a water delivery pump house, a raw water pump house (pump station), a municipal pressure water delivery pipe network and the like of a municipal water supply plant water discharge plant for exhausting, and because air is usually present in the water delivery pipeline, under the combined action of water flow and air flow, pipe bursting can often occur, especially in a conveying system with longer conveying pipeline and larger gradient fluctuation, if water stopping or air accumulation in the pipeline occurs under the condition, water blocking flow is not smooth and even water stopping can occur, in addition, a plurality of water delivery pipelines adopt PVC (polyvinyl chloride) pipes, when water consumption is overlarge, the pipelines are easily sucked flat due to the negative pressure effect in the pipes, deformation or rupture can easily occur, large-area water stopping is easy to occur, normal life of people is influenced, a large amount of manpower and material resources are consumed for rush repair, and great problems are brought to normal water supply.

Aiming at the phenomenon, the floating ball type exhaust valve is used for water blocking and exhaust in the market at present, and the durability of the floating ball is poor due to friction of the floating ball at the exhaust port. The floating ball floats on the water surface to block the exhaust port when the water is positive pressure, and can be stuck with the joint for a long time without falling down, and the floating ball cannot work normally when exhausting next time. When negative pressure is sucked, the negative pressure is always not equal to the water level and is directly sucked to the floating ball to seal the exhaust port, so that the water level cannot rise. The technology has frequent misoperation and low safe operation coefficient.

In addition, in long-distance water delivery, the air bags which can remove most of air are arranged at the crossing siphon positions and cannot be removed are arranged in the siphon pipelines, the air bags exist in the pipelines and are difficult to remove or excessively long in removal time, the water pressure and the water quantity of downstream water factories and industrial enterprises are influenced, hidden danger is formed on pipeline safety, therefore, a mechanical vacuum extraction device is required to be matched, vacuum is formed by mechanical assistance on crossing the siphon, pipeline air can be removed rapidly, the pipeline air removal time is shortened, residual air is removed, but after the siphon in the pipeline is formed, the pipeline is in a negative pressure state, the existing automatic exhaust valve automatically sucks air to destroy the siphon formation, so that the siphon water delivery cannot be effectively utilized, and therefore, aiming at the prior art, the design and production of a water blocking exhaust valve suitable for positive and negative pressure working conditions is urgently needed to meet the requirement of actual use.

Disclosure of utility model

The utility model provides a water-blocking exhaust valve suitable for positive and negative pressure working conditions, and solves the technical problems in the background art.

In order to solve the technical problems, the water-blocking exhaust valve suitable for the positive and negative pressure working conditions comprises a main tank body, wherein the bottom of the main tank body is provided with a water inlet, a main valve body is fixedly arranged in the main tank body, a check ball is arranged on the upper portion of the main valve body and is made of polytetrafluoroethylene, a blocking piston is movably arranged on the lower portion of the main valve body, a connecting fixing rod is arranged at the bottom end thread of the blocking piston, a thimble is movably arranged at the lower end of the connecting fixing rod, a floating ball is arranged at the lower end thread of the thimble, and the floating ball is hollow and spherical.

Preferably, the top of the main tank body is provided with the end cover through the flange plate, the top of the end cover and the bottom of the main tank body are integrally provided with the connecting column, the inner wall of the connecting column is provided with the internal thread, the bottom of the inner cavity of the main tank body is fixedly provided with the anti-impact baffle through the connecting rod, the anti-impact baffle is positioned under the floating ball, and the anti-impact baffle is positioned above the bottom connecting column.

Preferably, the main valve body fixed mounting is in the bottom surface of end cover, the circular through groove has been seted up at the middle part of the main valve body, the inner wall middle part in circular through groove is integrated into one piece has the installation arch, first draw-in groove has been seted up at the bellied top of installation, the bellied bottom fixed mounting of installation has protruding piece, the circulation groove has been seted up at the middle part of protruding piece, the bellied upper and lower both sides of circulation groove intercommunication installation, main valve body gas vent has been seted up to the side of the main valve body, main valve body gas vent is located the bellied below of installation, the O type circle is installed in the inside mosaic of first draw-in groove, the check ball is arranged in the top of O type circle.

Preferably, the bottom of the main valve body is provided with a lower fixing plate through a screw, the edge of the lower fixing plate is not attached to the inner wall of the main tank body, and the plugging piston is movably arranged in the middle of the lower fixing plate.

Preferably, the plugging piston comprises a piston main body, the piston main body is cylindrical, a supporting plate is integrally formed in the middle of the piston main body, a sealing cylinder matched with the inner diameter of the circulation groove is integrally formed at the top of the supporting plate, a second clamping groove is formed among the sealing cylinder, the piston main body and the supporting plate, a piston pad is mounted in the second clamping groove in an embedded mode, a buffer pipeline is integrally formed at the bottom of the supporting plate, a bottom groove is formed among the buffer pipeline, the piston main body and the supporting plate, a buffer hole which is mutually communicated is formed in the middle of the buffer pipeline and the sealing cylinder, threads are formed on the outer surface of the bottom end of the buffer pipeline, and the inner diameter of the bottom end of the buffer hole is 2mm.

Preferably, the connecting and fixing rod is cylindrical, threads in threaded connection with the bottom end of the buffer pipeline are formed on the upper side of the inner wall of the connecting and fixing rod, a vent is formed in the side face of the connecting and fixing rod, and the bottom end of the connecting and fixing rod is a step column.

Preferably, the top surface fixed mounting of thimble has the thimble cushion, the top movable mounting of thimble is in the inside of connecting the dead lever, the surface of thimble cushion is laminated mutually with the inner wall of connecting the dead lever.

Compared with the related art, the water-blocking exhaust valve suitable for the positive and negative pressure working conditions provided by the utility model has the following structure

The beneficial effects are that:

The utility model provides a water-blocking exhaust valve suitable for positive and negative pressure working conditions, which is used for exhausting gas at the top end of a water pump when the water-blocking exhaust valve is arranged at the top end of the water pump, when the upper part of a main tank body is connected with a negative pressure pipeline or the water level is higher than that of water of the water pump under positive pressure, so that the water pump can be directly started, and gas accumulated at a hump at the top end of the water pump can be exhausted when the water pump runs for a long time, thereby reducing the surging of the water pump and ensuring the safe running of the water pump.

The utility model provides a water-blocking exhaust valve suitable for positive and negative pressure working conditions, which is arranged at a high point position in a shape like a Chinese character 'ji' when crossing a river channel or various obstacles in a water pipe network and is used for exhausting gas and preventing water from being exhausted outwards.

The water-blocking exhaust valve suitable for the positive and negative pressure working conditions provided by the utility model can be suitable for the positive and negative pressure working conditions, is stable in operation and high in safe operation coefficient, and avoids the phenomena of blocking the exhaust port by a floating ball.

Drawings

FIG. 1 is a schematic diagram of the overall structure of the present utility model;

FIG. 2 is a schematic cross-sectional view of a main tank of the present utility model;

FIG. 3 is a schematic view of the overall cross-sectional structure of the present utility model;

FIG. 4 is an enlarged schematic view of the upper half of the overall cross-section of the present utility model;

FIG. 5 is an enlarged schematic view of the lower half of the whole section structure of the present utility model;

FIG. 6 is a schematic view of the main valve body structure of the present utility model;

FIG. 7 is a schematic cross-sectional view of a main valve body according to the present utility model;

FIG. 8 is a schematic illustration of a plugging piston structure according to the present utility model;

FIG. 9 is a schematic cross-sectional view of a plugging piston according to the present utility model;

FIG. 10 is a schematic view of a connecting rod structure according to the present utility model;

FIG. 11 is a schematic cross-sectional view of a connecting rod according to the present utility model;

FIG. 12 is a schematic view of a thimble structure according to the present utility model;

FIG. 13 is a schematic cross-sectional view of a thimble according to the present utility model;

fig. 14 is a schematic view of the structure of the main valve body and the plugging piston of the present utility model when sealing.

Reference numerals in the drawings: 1. a main tank body; 2. a main valve body; 3. a check ball; 4. plugging the piston; 5. connecting a fixed rod; 6. a thimble; 7. a floating ball; 201. an O-ring; 202. a lower fixing plate; 401. a piston pad; 601. a thimble rubber pad; 21. round through grooves; 22. mounting the bulge; 23. a first clamping groove; 24. a protruding member; 25. a flow channel; 26. an exhaust port of the main valve body; 40. a piston body; 41. a support plate; 42. a sealing cylinder; 43. a second clamping groove; 44. a buffer pipe; 45. a bottom groove; 46. buffering holes; 51. a vent; 52. a step post.

Detailed Description

The embodiment is given by figures 1-5, the utility model comprises a main tank body 1, the bottom of the main tank body 1 is a water inlet, a main valve body 2 is fixedly arranged in the main tank body 1, a check ball 3 is arranged at the upper part of the main valve body 2, the check ball 3 is solid spherical and is made of polytetrafluoroethylene, a plugging piston 4 is movably arranged at the lower part of the main valve body 2, a connecting fixing rod 5 is arranged at the bottom end thread of the plugging piston 4, a thimble 6 is movably arranged at the lower end of the connecting fixing rod 5, a floating ball 7 is arranged at the lower end thread of the thimble 6, and the floating ball 7 is hollow spherical and is made of SS 304.

In the embodiment, the main tank body 1 can be arranged at the top end of the water pump, and can also be arranged at a high point position in a shape like a Chinese character 'ji' when crossing a river channel or various obstacles in a water pipe network, and is used for exhausting gas and preventing water from being exhausted outwards;

Under the positive pressure working condition, the top of the main tank body 1 is used as an exhaust port, the positive pressure enables the water level to rise to the water inlet at the lower part of the main tank body 1 and then enters the tank body, gas in the tank body 1 is exhausted upwards through the exhaust port of the main valve body 2, the check ball 3 in the main valve body 2 can be jacked upwards by the gas, at the moment, the gas in the main tank body 1, a pipeline at the lower part and equipment is exhausted outwards, when the water level reaches the height of the floating ball 7, the floating ball 7 carries the thimble 6 upwards to jack the plugging piston 4 by the buoyancy of water, the plugging piston 4 is sealed by the thimble 6, the plugging piston 4 is sealed by the water level stops rising when the water pressure in the tank body 1 is the same as the air pressure;

When the air content in the water is small or no, the main valve body 2 can be sealed by the floating ball 7, and the water level is always kept at the water level; at this time, if the pressure in the water is low, the check ball 3 of the main valve body 2 can be used for sealing the exhaust port so as to enable the water level to be always suspended at the water level;

When the gas contained in the water is too much and the gas floats upwards and gathers in the main tank body 1, the floating ball 7 descends along with the self gravity of the thimble 6 when the buoyancy of the water is not available, and the plugging piston 4 descends by being pulled downwards through the connecting fixing rod 5, so that the internal and external air pressure of the plugging piston 4 is the same due to the up-down communication of the plugging piston 4, and the plugging piston 4 can descend at the moment;

Under the negative pressure working condition, the upper part of the main tank body 1 is provided with an extraction opening and is connected with a negative pressure pipeline, the check ball 3 is lifted upwards along with the negative pressure, the air outlet of the main valve body 2 upwards discharges the air in the tank, the pipeline at the lower part and the equipment at the lower part, when the negative pressure pumps the water level to the position of the floating ball 7 in the tank, the floating ball 7 and the thimble 6 are lifted upwards, the thimble 6 props against the plugging piston 4 and props up the plugging piston 4, the sealing between the plugging piston 4 and the main valve body 2 stops outwards exhausting, and the water level stops rising at the moment;

When the air content in the water is very small or no, the water can be suspended at the water level by means of the check ball 3;

When the air content in the water in the lower pipeline equipment floats upwards in the tank, the floating ball 7 and the thimble 6 drive the connecting and fixing rod 5 to drop downwards, and the plugging piston 4 drops downwards after being communicated with the upper part and the lower part in the plugging piston 4; at this time, the negative pressure pipeline sucks the water level again to jack up the floating ball 7.

As shown in fig. 1-4, an end cover is installed on the top of the main tank body 1 through a flange plate, connecting columns are integrally formed on the top of the end cover and the bottom of the main tank body 1, internal threads are arranged on the inner wall of the connecting columns, an anti-impact baffle is fixedly installed on the bottom of an inner cavity of the main tank body 1 through a connecting rod, and is located under the floating ball 7 and above the connecting columns at the bottom.

In this embodiment, the internal thread that sets up through the spliced pole is convenient to be connected with other equipment to avoid directly striking floater 7 through the scour protection baffle that sets up from the water inlet and cause the error.

As shown in fig. 6-7, the main valve body 2 is fixedly installed on the bottom surface of the end cover, the middle part of the main valve body 2 is provided with a circular through groove 21, the middle part of the inner wall of the circular through groove 21 is integrally formed with an installation protrusion 22, the top of the installation protrusion 22 is provided with a first clamping groove 23, the bottom of the installation protrusion 22 is fixedly provided with a protrusion piece 24, the middle part of the protrusion piece 24 is provided with a circulation groove 25, the circulation groove 25 is communicated with the upper side and the lower side of the installation protrusion 22, the side surface of the main valve body 2 is provided with a main valve body exhaust port 26, the main valve body exhaust port 26 is located below the installation protrusion 22, the inside of the first clamping groove 23 is embedded with an O-shaped ring 201, and the check ball 3 is arranged above the O-shaped ring 201.

In this embodiment, the main valve body 2 is made of SS304, the O-ring 201 is made of fluororubber, the chemical property between the O-ring and the check ball 3 made of polytetrafluoroethylene is stable, the molecular structure of polytetrafluoroethylene is a linear structure, the molecular structure of polytetrafluoroethylene has lower stretching and bending characteristics, the check ball 3 is not easy to deform, the fluororubber has the advantages of higher chemical corrosion resistance, being capable of resisting acid, alkali, organic solvent and other chemical products, and the polytetrafluoroethylene has more excellent corrosion resistance, and is basically not corroded by any chemical substances.

As shown in fig. 4, the bottom of the main valve body 2 is provided with a lower fixing plate 202 by screws, the edge of the lower fixing plate 202 is not attached to the inner wall of the main tank 1, and the plugging piston 4 is movably mounted in the middle of the lower fixing plate 202.

In this embodiment, firstly, the installation of the plugging piston 4 is facilitated by the lower fixing plate 202 provided, and secondly, the discharge of the gas is not affected.

As shown in fig. 8-9, the plugging piston 4 comprises a piston main body 40, the piston main body 40 is in a cylindrical shape, a supporting plate 41 is integrally formed in the middle of the piston main body 40, a sealing cylinder 42 matched with the inner diameter of the circulation groove 25 is integrally formed at the top of the supporting plate 41, a second clamping groove 43 is formed between the sealing cylinder 42, the piston main body 40 and the supporting plate 41, a piston pad 401 is embedded and installed in the second clamping groove 43, a buffer pipeline 44 is integrally formed at the bottom of the supporting plate 41, a bottom groove 45 is formed among the buffer pipeline 44, the piston main body 40 and the supporting plate 41, a buffer hole 46 communicated with each other is formed in the middle of the buffer pipeline 44 and the sealing cylinder 42, threads are formed on the outer surface of the bottom end of the buffer pipeline 44, and the inner diameter of the bottom end of the buffer hole 46 is 2mm.

In this embodiment, the plugging piston 4 can be matched with the main valve body 2, so that the bottom surface of the protruding piece 24 is attached to the top surface of the piston pad 401, and a sealing state can be formed; wherein, the negative pressure contained in the buffer hole with the thickness of 2mm is smaller than the self gravity of the floating ball 7 and the thimble 6; it should be noted that the inner diameter of 2mm can be adjusted and set to other suitable inner diameters according to the self-gravity of the floating ball 7 and the thimble 6.

As shown in fig. 10-11, the connecting and fixing rod 5 is cylindrical, threads in threaded connection with the bottom end of the buffer pipe 44 are provided on the upper side of the inner wall of the connecting and fixing rod 5, a vent 51 is provided on the side surface of the connecting and fixing rod 5, and a step column 52 is provided at the bottom end of the connecting and fixing rod 5.

In this embodiment, the connection fixing rod 5 is detachable, the connection fixing rod 5 can enable the thimble 6 to move up and down, and the connection is realized through the vent hole 51, and the sealing is realized when the thimble 6 ascends

As shown in fig. 12-13, a thimble rubber pad 601 is fixedly mounted on the top surface of the thimble 6, the top end of the thimble 6 is movably mounted in the connecting and fixing rod 5, and the outer surface of the thimble rubber pad 601 is attached to the inner wall of the connecting and fixing rod 5.

In this embodiment, the thimble 6 is used for connecting the floating ball 7, and the sealing effect is increased by the thimble rubber pad 601.

Working principle: the water-blocking exhaust valve is designed for adapting to positive and negative pressure working conditions, can be arranged at the top end of a water pump, can also be arranged at a high point position like a Chinese character 'ji' in a water pipe network when crossing a river channel or various obstacles, is used for exhausting gas and preventing water from being exhausted outwards, is arranged at the top end of the water pump, and is used for exhausting gas at the top end of the water pump when the upper part of the main tank body 1 is connected with a negative pressure pipeline or the water level is higher than that of the water pump when the water pump is in positive pressure so as to enable the water pump to be directly started, and can also exhaust gas accumulated at the top end of the water pump in hump when the water pump runs for a long time, thereby reducing water pump surge and ensuring the safe running of the water pump; when the device is arranged at the high-point position of the Chinese character 'ji', the gas accumulated by water in the water pipe network for a long time can be discharged through the high-point position of the Chinese character 'ji', and the problem of insufficient water flow in the water pipe network caused by gas accumulation is avoided.

The invention is mainly used for exhausting urban water transmission pipe network in water industry and exhausting water pump in water delivery pump house or raw water pump house of water treatment plant, the device can effectively improve the operation efficiency of pipe network and water pump during water transmission, effectively improve the operation safety, reduce the preparation time during operation, is suitable for various working conditions, and is simple and convenient to install.

When the equipment is installed in a water delivery pump room and a raw water pump room of a water treatment plant, a liquid level forming switch can be additionally arranged in the main tank body, so that the operation of the equipment and a water pump in a linkage way is realized, and the operation trend of an unattended water plant is met.

The working process comprises the following steps:

The main tank body 1 can be arranged at the top end of a water pump or can be arranged at a high point position in a shape like a Chinese character 'ji' when a water pipe net passes over a river channel or various obstacles, and is used for exhausting gas and preventing water from being exhausted outwards;

Under the positive pressure working condition, the top of the main tank body 1 is an exhaust port, positive pressure enables the water level to rise to a water inlet at the lower part of the main tank body 1 and then enters the tank body, gas in the tank body 1 is exhausted upwards through the exhaust port of the main valve body 2, the check ball 3 in the main valve body 2 can be jacked upwards by the gas, at the moment, the gas in the main tank body 1, a pipeline at the lower part and equipment is exhausted outwards, when the water level reaches the height of the floating ball 7, the floating ball 7 carries the thimble 6 to jack the plugging piston 4 upwards by the buoyancy of water, the thimble 6 seals a buffer hole 46 in the center of the plugging piston 4, the plugging piston 4 seals the exhaust port 26 of the main valve body, and at the moment, the water level stops rising when the water pressure in the main tank body 1 is the same as the air pressure;

When the air content in the water is small or no, the air outlet 26 of the main valve body can be sealed by the floating ball 7, and the water level is always kept at the water level; at this time, if the pressure in the water is low, the check ball 3 of the main valve body 2 can be used for sealing the exhaust port so as to enable the water level to be always suspended at the water level;

When the gas contained in the water is too much and the gas floats upwards and gathers in the main tank body 1, the floating ball 7 descends along with the self gravity of the thimble 6 when the buoyancy of the water is not available, and the plugging piston 4 descends by being pulled downwards through the connecting fixing rod 5, the buffer hole 46 in the center of the plugging piston 4 is communicated up and down, so that the gas pressure in the main valve body exhaust port 26 sealed by the plugging piston 4 is the same as the gas pressure in the lower tank body, and at the moment, the plugging piston 4 can descend;

Under the negative pressure working condition, the upper part of the main tank body 1 is provided with an extraction opening and is connected with a negative pressure pipeline, the check ball 3 is lifted upwards along with the negative pressure, the air outlet of the main valve body 2 is used for exhausting the air in the tank, the pipeline at the lower part and the equipment at the upper part, when the negative pressure pumps the water level to the position of the floating ball 7 in the tank, the floating ball 7 and the thimble 6 are lifted upwards, the thimble 6 props against the buffer hole 46 with the diameter of 2mm at the center of the plugging piston 4 and props up the plugging piston 4, the O-shaped ring 201 on the plugging piston 4 and the main valve body 2 are sealed to stop exhausting outwards, and the water level stops rising at the moment;

When the air content in the water in the lower pipeline equipment floats upwards in the tank, the floating ball 7 and the thimble 6 slowly rise out of the water surface, when the air content is completely separated from the water surface, the gravity of the floating ball 7 and the thimble 6 is larger than the negative pressure in a 2mm diameter hole at the bottom end of the buffer hole 46 in the plugging piston 4, so that the thimble rubber pad 601 at the top of the thimble 6 is separated from the bottom end of the buffer hole 46 of the plugging piston 4, then the floating ball 7 and the thimble 6 drive the connecting fixing rod 5 to drop downwards, the connecting fixing rod 5 and the plugging piston 4 form a whole through threaded connection, and the pressure on the upper and lower sides of the piston is the same after the 2mm diameter buffer hole 46 in the inner center of the plugging piston 4 is communicated, so that the plugging piston 4 drops downwards together with the floating ball 7, the thimble 6 and the connecting fixing rod 5, and at the moment, the negative pressure pipeline sucks the water level again, so that the floating ball 7 jacks upwards.

Claims

1. The utility model provides a be fit for discharge valve that blocks water of positive and negative pressure operating mode, its characterized in that, including main jar body (1), the bottom of main jar body (1) is the water inlet, the inside fixed mounting of main jar body (1) has main valve body (2), main valve body (2) upper portion is equipped with ends the ball (3), and check ball (3) are solid spheroidal, uses polytetrafluoroethylene to make, the lower part movable mounting of main valve body (2) has shutoff piston (4), the bottom screw thread of shutoff piston (4) is installed and is connected dead lever (5), the lower extreme movable mounting of connecting dead lever (5) has thimble (6), the lower extreme screw thread of thimble (6) is installed floater (7), and floater (7) are hollow spheroidal.

2. The water-blocking exhaust valve suitable for positive and negative pressure working conditions according to claim 1, wherein the top of the main tank body (1) is provided with an end cover through a flange plate, the top of the end cover and the bottom of the main tank body (1) are integrally provided with connecting columns, the inner walls of the connecting columns are provided with internal threads, the bottom of an inner cavity of the main tank body (1) is fixedly provided with a shock-proof baffle through a connecting rod, the shock-proof baffle is positioned under the floating ball (7), and the shock-proof baffle is positioned above the connecting columns at the bottom.

3. The water-blocking exhaust valve suitable for positive and negative pressure working conditions according to claim 1, wherein the main valve body (2) is fixedly installed on the bottom surface of the end cover, a circular through groove (21) is formed in the middle of the main valve body (2), an installation protrusion (22) is integrally formed in the middle of the inner wall of the circular through groove (21), a first clamping groove (23) is formed in the top of the installation protrusion (22), a protruding piece (24) is fixedly installed at the bottom of the installation protrusion (22), a circulation groove (25) is formed in the middle of the protruding piece (24), the circulation groove (25) is communicated with the upper side and the lower side of the installation protrusion (22), a main valve body exhaust port (26) is formed in the side surface of the main valve body (2), an O-shaped ring (201) is embedded in the inner portion of the first clamping groove (23), and the check ball (3) is arranged above the O-shaped ring (201).

4. A water-blocking exhaust valve suitable for positive and negative pressure working conditions according to claim 3, characterized in that a lower fixing plate (202) is arranged at the bottom of the main valve body (2) through screws, the edge of the lower fixing plate (202) is not attached to the inner wall of the main tank body (1), and the blocking piston (4) is movably arranged in the middle of the lower fixing plate (202).

5. The water-blocking exhaust valve suitable for positive and negative pressure working conditions according to claim 4, wherein the blocking piston (4) comprises a piston main body (40), the piston main body (40) is cylindrical, a supporting plate (41) is integrally formed in the middle of the piston main body (40), a sealing cylinder (42) matched with the inner diameter of the circulation groove (25) is integrally formed at the top of the supporting plate (41), a second clamping groove (43) is formed between the sealing cylinder (42), the piston main body (40) and the supporting plate (41), a piston pad (401) is embedded in the second clamping groove (43), a buffer pipeline (44) is integrally formed at the bottom of the supporting plate (41), a bottom groove (45) is formed among the buffer pipeline (44), the piston main body (40) and the supporting plate (41), a buffer hole (46) which is mutually communicated is formed in the middle of the buffer pipeline (44), threads are formed on the outer surface of the bottom end of the buffer pipeline (44), and the inner diameter of the bottom end of the buffer hole (46) is 2mm.

6. The water-blocking exhaust valve suitable for positive and negative pressure working conditions according to claim 1, wherein the connecting and fixing rod (5) is cylindrical, threads connected with the bottom end of the buffer pipeline (44) are formed on the upper side of the inner wall of the connecting and fixing rod (5), an air vent (51) is formed in the side face of the connecting and fixing rod (5), and a step column (52) is arranged at the bottom end of the connecting and fixing rod (5).

7. The water-blocking exhaust valve suitable for positive and negative pressure working conditions according to claim 1, wherein an ejector pin rubber pad (601) is fixedly arranged on the surface of the top end of the ejector pin (6), the top end of the ejector pin (6) is movably arranged in the connecting and fixing rod (5), and the outer surface of the ejector pin rubber pad (601) is attached to the inner wall of the connecting and fixing rod (5).