CN110145620B - Full-plastic diaphragm type one-way exhaust check valve with emergency ventilation function - Google Patents
Full-plastic diaphragm type one-way exhaust check valve with emergency ventilation function Download PDFInfo
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- CN110145620B CN110145620B CN201910260031.3A CN201910260031A CN110145620B CN 110145620 B CN110145620 B CN 110145620B CN 201910260031 A CN201910260031 A CN 201910260031A CN 110145620 B CN110145620 B CN 110145620B
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- valve
- valve plate
- gas purification
- ventilation function
- valve body
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K15/00—Check valves
- F16K15/14—Check valves with flexible valve members
- F16K15/144—Check valves with flexible valve members the closure elements being fixed along all or a part of their periphery
- F16K15/147—Check valves with flexible valve members the closure elements being fixed along all or a part of their periphery the closure elements having specially formed slits or being of an elongated easily collapsible form
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K24/00—Devices, e.g. valves, for venting or aerating enclosures
- F16K24/04—Devices, e.g. valves, for venting or aerating enclosures for venting only
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Check Valves (AREA)
- Respiratory Apparatuses And Protective Means (AREA)
- Professional, Industrial, Or Sporting Protective Garments (AREA)
Abstract
The invention relates to an all-plastic diaphragm type one-way exhaust check valve with an emergency ventilation function, which comprises a valve body, wherein a first valve plate installation cavity and a gas purification assembly installation cavity are arranged in the valve body; the side face of the valve body is located above the first valve plate mounting cavity and is provided with a dome part, a supporting sheet breaking column is fixed on the inner wall of the dome part, the valve can rapidly change the one-way check function of the first valve plate by forcibly pressing the dome part on the valve body in an emergency state of losing an air source, and meanwhile, the sealing structure of the second valve plate can be rapidly broken manually, so that the two-way flow of air flow is realized, and the breathing requirement of a wearer in the emergency state is met.
Description
Technical Field
The invention relates to the safety field of protective clothing, in particular to a full-plastic diaphragm type one-way exhaust check valve with an emergency ventilation function.
Background
The closed protective clothing is important protective equipment for protecting the life safety and health of workers, emergency rescue workers and the public in case of accidents in dangerous environments, is widely applied to industries such as chemical industry, petroleum industry, nuclear industry, military industry, mines and the like, and plays an important role in industrial production and emergency rescue of accidents.
The closed protective clothing works in a toxic and harmful environment, clean breathing air needs to be provided for a protective clothing wearer, and two technical schemes are generally adopted in the existing closed protective clothing in order to prevent air source interruption from threatening the life safety of the protective clothing wearer.
The utility model provides a scheme adopts emergent air supply air feed, if carry the gas cylinder by the protective clothing person of dress and get into dangerous place, when normal air supply was interrupted, can switch the air feed to the gas cylinder, satisfied protective clothing person of dress short time breathing needs.
Another approach employs a respiratory protector, such as a respirator carried by the wearer of the protective garment into a hazardous location, which is broken when the normal air supply is interrupted, and then worn to prevent inhalation of harmful substances by the wearer of the protective garment.
Both of these schemes have drawbacks:
in the first scheme, the protective clothing needs to be carried with the gas cylinder to enter a dangerous environment, so that the burden of a wearer of the protective clothing is increased, and the rapid evacuation of personnel is not facilitated. Meanwhile, the gas cylinder is used as an emergency gas source, so that the equipment investment is increased, and decontamination treatment is needed after the gas cylinder and the like enter a polluted environment.
The second scheme needs to damage the sealed protective clothing, and although the breathing requirements of personnel are met, the damage of skin pollution of the personnel is inevitable, and the damage to the sealed protective clothing is unacceptable particularly in a strong acid-base corrosive environment, a toxic substance environment and a radioactive aerosol dust environment.
The exhaust valve is an important component of the airtight protective clothing, and not only does the exhaust valve need to ensure the airtight performance of the airtight protective clothing and meet the internal exhaust requirement of the protective clothing, but also needs to prevent external toxic and harmful gases from entering the airtight protective clothing through the exhaust valve. Negative pressure may form inside the suit due to changes in air supply pressure, movement or changes in body position of the wearer of the suit, etc., at which time the vent valve must also prevent reverse air flow from entering the inside of the suit. Some discharge valves need to use metal materials such as springs and valve plates, and when the metal materials work in a corrosive environment, the strength is reduced due to corrosion, and the sealing performance is reduced, so that hidden troubles are brought.
Disclosure of Invention
The invention aims to solve the defects in the prior art and provides an all-plastic diaphragm type one-way exhaust check valve with an emergency ventilation function.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a full-plastic diaphragm type one-way exhaust check valve with an emergency ventilation function comprises a valve body, wherein an annular fixing plate is arranged in the valve body, the annular fixing plate encloses a first valve plate installation cavity, the annular fixing plate and a frame of the valve body enclose a gas purification assembly installation cavity, an outer clamping fastening fixing piece is arranged on the side face of the valve body, an exhaust port is formed in the outer clamping fastening fixing piece, a through hole communicated with the gas purification assembly installation cavity is formed in the annular fixing plate, and a first gas purification assembly is installed in the gas purification assembly installation cavity;
one side of the valve body is open, the other side of the valve body is sealed, and the side surface of the opening of the valve body is hermetically connected with an opening on the protective clothing;
the first valve plate is arranged in the first valve plate mounting cavity, a support sheet is arranged below the first valve plate, the peripheral surface of the support sheet is connected with the inner wall of the annular fixing plate in a sealing mode, a plurality of hollow parts and support reinforcing parts are arranged on the support sheet, and the first valve plate is provided with an exhaust crack which divides the first valve plate into a plurality of exhaust valve clacks;
a dome part is arranged on the side face of the valve body and above the first valve plate mounting cavity, a supporting sheet breaking column is fixed on the inner wall of the dome part, and the free end of the supporting sheet breaking column is close to the surfaces of the first valve plate and the supporting sheet.
Further, the exhaust port is provided with a second valve plate, and the outer clamping fastening firmware is connected with the second gas purification assembly in a clamping manner.
Furthermore, the second valve plate is an elastic plastic sheet and is fixed on an exhaust port of the outer card fastening firmware in a clamping groove mode.
Furthermore, a clamping groove is arranged on the outer card fastening firmware.
Furthermore, the shape of the first gas purification component is matched with the gas purification component installation cavity, and the first gas purification component is made of activated carbon or porous cotton.
Further, gaseous purification component of second includes the casing and places the filler in the casing, and one side opening of casing, the opposite side are equipped with the joint piece, the joint piece with draw-in groove block on the outer card straining firmware.
Furthermore, a sealing gasket is arranged at the connection position of the opening side surface of the valve body and the opening on the protective clothing.
Furthermore, the first valve plate is an elastic plastic sheet, and the exhaust crack is cross-shaped.
Further, a gap is reserved between the first valve plate and the dome portion.
Furthermore, the first valve plate is closely attached to the support sheet to form a first sealing surface from the outer side of the protective clothes to the inner side, and the second valve plate and an air outlet of the outer card fastening firmware form a second sealing surface.
The invention has the beneficial effects that: (1) the valve can rapidly change the one-way check function of the first valve plate by forcibly pressing the dome part on the valve body in the emergency state of losing the air source, and meanwhile, the sealing structure of the second valve plate can be rapidly destroyed manually, so that the bidirectional flow of air flow is realized, and the breathing requirement of a wearer in the emergency state is met.
(2) This valve is equipped with gaseous purifier, can realize carrying out purification treatment to external contaminated air under emergency to satisfy the wearer's safety in the short time.
(3) The valve adopts a two-stage sealing structure, the sealing reliability is enhanced, and pollutants can be effectively prevented from entering the inside of the gas coat through the exhaust hole when the protective clothing is under the instantaneous negative pressure.
(4) The valve can meet various air displacement requirements by adjusting the split length of the valve clack of the first valve plate, and particularly meets the requirement of large-flow air displacement of the long-pipe air supply positive pressure protective clothing.
(5) This valve accessible adopts different valve block adjustment valve opening pressure of material thickness and elasticity, and first valve block and second valve block can adopt different materials simultaneously, and when the internal and external pressure difference of protective clothing was greater than certain pressure, the valve block could be pushed open to inside atmospheric pressure, forms the exhaust.
(6) The valve is of a full-plastic structure and has no metal part, thereby being beneficial to the incineration treatment of the protective clothing.
(7) The valve has the advantages of simple and reliable structure, lower production and processing difficulty and low cost.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic view of the internal structure of the valve body of the present invention;
FIG. 3 is a schematic diagram of the first gas purification assembly according to the present invention;
FIG. 4 is a schematic structural diagram of the first valve plate according to the present invention;
fig. 5 is a schematic structural view of a support sheet according to the present invention;
FIG. 6 is a schematic diagram of a first gas purification assembly according to the present invention;
FIG. 7 is a schematic view of a gasket of the present invention;
FIG. 8 is a schematic view of the outer clip fastening member of the present invention with the second valve plate mounted thereon;
FIG. 9 is a schematic view of the second gas purification assembly of the present invention connected to an external card fastener;
FIG. 10 is a schematic diagram of a second gas purification assembly according to the present invention.
Detailed Description
As shown in fig. 1 to 10, an all-plastic diaphragm type one-way exhaust check valve with an emergency ventilation function comprises a valve body 1, wherein an annular fixing plate 2 is arranged in the valve body 1, a first valve plate installation cavity 3 is defined by the annular fixing plate 2, a gas purification assembly installation cavity 4 is defined by the annular fixing plate 2 and a frame of the valve body, an outer clamping fastening fastener 5 is arranged on the side surface of the valve body 1, an exhaust port 6 is arranged on the outer clamping fastening fastener 5, a through hole 7 communicated with the gas purification assembly installation cavity 4 is arranged on the annular fixing plate 2, and a first gas purification assembly 8 is arranged in the gas purification assembly installation cavity 4;
one side of the valve body 1 is open, the other side is sealed, and the side surface of the opening of the valve body 1 is hermetically connected with an opening on the protective clothing;
a first valve plate 9 is arranged in the first valve plate mounting cavity 3, a support sheet 10 is arranged below the first valve plate 9, the peripheral surface of the support sheet 10 is connected with the inner wall of the annular fixing plate 2 in a sealing manner, a plurality of hollow parts 11 and support reinforcing parts 12 are arranged on the support sheet 10, an exhaust crack 13 is arranged on the first valve plate 9, and the first valve plate 9 is divided into a plurality of exhaust valve flaps by the exhaust crack 13;
a dome part 14 is arranged on the side surface of the valve body 1 above the first valve plate mounting cavity 3, a support sheet breaking column 15 is fixed on the inner wall of the dome part 14, and the free end of the support sheet breaking column 15 is close to the surfaces of the first valve plate 9 and the support sheet 10.
Further, the exhaust port 6 is provided with a second valve plate 16, and the outer clamping fastening piece 5 is connected with a second gas purification component 17 in a clamping manner. The second valve plate 16 is preferably an elastic plastic sheet, the second valve plate 16 can be made of different materials, for example, the second valve plate 16 is made of a thick PVC valve plate, when the pressure difference between the inside and the outside of the protective suit is greater than a certain pressure, the internal air pressure can push the valve plate open to form exhaust, and the second valve plate 16 is fixed to the exhaust port 6 of the external card fastening fastener in a clamping groove mode. The outer card fastening fastener 5 is provided with a card slot 18.
Further, the shape of the first gas purification assembly 8 is matched with the gas purification assembly installation cavity 4, and the first gas purification assembly 8 is made of general long-life gas purification materials (such as activated carbon, porous cotton and the like).
Further, the second gas purification assembly 17 comprises a shell and a filler arranged in the shell, wherein an opening is formed in one side of the shell, a clamping block 19 is arranged on the other side of the shell, and the clamping block 19 is clamped with a clamping groove 18 in the outer clamping fastening piece 5.
In the invention, a sealing gasket 20 is arranged at the connection part of the opening side surface of the valve body 1 and the opening on the protective clothing, the first valve plate 9 is an elastic plastic sheet, and the exhaust crack 13 is in a cross shape. A gap is left between the first valve plate 9 and the dome part 14. The first valve plate 9 is closely attached to the support plate 10 to form a first sealing surface from the outer side to the inner side of the protective clothes, and the second valve plate 16 and the exhaust port 6 of the outer card fastening fastener form a second sealing surface.
The invention has the following characteristics:
(1) one-way exhaust and non-return function:
under normal conditions, the inside malleation that is of protective clothing, the inside gas of protective clothing passes through the protective clothing trompil, promote the flap valve of first valve block 9 behind the fretwork portion 11 of backing sheet 10, the valve flap of first valve block 9 is opened under the air current effect of certain pressure, open with the first sealed face that backing sheet 10 formed, then the air current gets into in the gas purification subassembly installation cavity 4 from through-hole 7 on the annular fixed plate 2 and is purified by first gas purification subassembly 8, gas after the purification gets into gas vent 6 and promotes second valve block 16 and outwards opens, the inside gas of protective clothing realizes one-way emission.
When instantaneous pressure fluctuation or negative pressure occurs in the protective suit due to pressure fluctuation of the air supply source, movement or body position change of a wearer and the like, the second valve plate 16 is quickly closed by the elasticity of the second valve plate and the internal and external pressure difference, and forms a second sealing surface with the exhaust port 6 of the external card fastening fastener; due to the loss of the air flow, the first valve plate 9 recovers to be flat under the action of self resilience force and is tightly attached to the support sheet 10 to form a first sealing surface. The reverse flow of the airflow under the transient negative pressure state is prevented.
(2) Emergency ventilation and purification function
In the emergency state of losing the air supply, the clamped second valve plate 16 is firstly torn off, and then the second air purification component 17 is butted with the clamping groove 18 of the outer clamping fastening firmware.
Then the dome part 14 is pressed with force, the supporting sheet 10 is broken under the action of the supporting sheet breaking column 15 in the dome part 14, the sealing surface is broken, and the first valve sheet 9 is opened in two directions.
At the moment, the air flow inside and outside the protective clothing can realize bidirectional flow, and the outside air flow enters the protective clothing after passing through the two-stage purification of the second air purification component 17 and the first air purification component 8.
In an emergency state of losing an air source, the valve can quickly change the one-way check function of the first valve plate by pressing the top of the dome on the valve body with force, and meanwhile, the sealing structure of the second valve plate can be quickly destroyed manually, so that the bidirectional flow of air flow is realized, and the breathing requirement of a wearer in the emergency state is met; the valve is provided with the gas purification device, so that the purification treatment of the outside polluted air can be realized in an emergency state, and the safety of a wearer in a short time can be met; the valve adopts a two-stage sealing structure, so that the sealing reliability is enhanced, and pollutants can be effectively prevented from entering the inside of the gas coat through the vent hole when the protective clothing is subjected to instantaneous negative pressure; the valve can meet various air displacement requirements by adjusting the split length of the valve clack of the first valve plate, and particularly meets the requirement of large-flow air displacement of the long-pipe air supply positive pressure protective clothing. This valve accessible adopts different valve block adjustment valve opening pressure of material thickness and elasticity, and first valve block and second valve block can adopt different materials simultaneously, and when the internal and external pressure difference of protective clothing was greater than certain pressure, the valve block could be pushed open to inside atmospheric pressure, forms the exhaust. The valve is of a full-plastic structure and has no metal part, thereby being beneficial to the incineration treatment of the protective clothing. The valve has the advantages of simple and reliable structure, lower production and processing difficulty and low cost.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (10)
1. A full-plastic diaphragm type one-way exhaust check valve with an emergency ventilation function comprises a valve body and is characterized in that an annular fixing plate is arranged in the valve body, a first valve plate mounting cavity is defined by the annular fixing plate, a gas purification assembly mounting cavity is defined by the annular fixing plate and a frame of the valve body, an outer clamping fastening piece is arranged on the side surface of the valve body, an exhaust port is formed in the outer clamping fastening piece, a through hole communicated with the gas purification assembly mounting cavity is formed in the annular fixing plate, and a first gas purification assembly is mounted in the gas purification assembly mounting cavity;
one side of the valve body is open, the other side of the valve body is sealed, and the side surface of the opening of the valve body is hermetically connected with an opening on the protective clothing;
the first valve plate is arranged in the first valve plate mounting cavity, a support sheet is arranged below the first valve plate, the peripheral surface of the support sheet is connected with the inner wall of the annular fixing plate in a sealing mode, a plurality of hollow parts and support reinforcing parts are arranged on the support sheet, and the first valve plate is provided with an exhaust crack which divides the first valve plate into a plurality of exhaust valve clacks;
a dome part is arranged on the side face of the valve body and above the first valve plate mounting cavity, a supporting sheet breaking column is fixed on the inner wall of the dome part, and the free end of the supporting sheet breaking column is close to the surfaces of the first valve plate and the supporting sheet.
2. The all-plastic membrane type one-way exhaust check valve with emergency ventilation function as claimed in claim 1, wherein the exhaust port is provided with a second valve plate, and an external fastening fastener is connected with the second gas purification component in a clamping manner.
3. The all-plastic diaphragm type one-way exhaust check valve with emergency ventilation function as claimed in claim 2, wherein the second valve plate is an elastic plastic sheet, and the second valve plate is fixed to the exhaust port of the external fastening fastener in a clamping manner.
4. The all-plastic diaphragm type one-way exhaust check valve with emergency ventilation function as claimed in claim 2, wherein the external fastening fastener is provided with a slot.
5. The all-plastic diaphragm type one-way exhaust check valve with the emergency ventilation function as claimed in claim 4, wherein the shape of the first gas purification component is matched with the mounting cavity of the gas purification component, and the first gas purification component is made of activated carbon or porous cotton.
6. The all-plastic diaphragm type one-way exhaust check valve with the emergency ventilation function as claimed in claim 4, wherein the second gas purification component comprises a shell and a filler arranged in the shell, one side of the shell is provided with an opening, the other side of the shell is provided with a clamping block, and the clamping block is clamped with a clamping groove on the external clamping fastening fastener.
7. The all-plastic diaphragm type one-way exhaust check valve with the emergency ventilation function as claimed in claim 1, wherein a sealing gasket is arranged at the joint of the side surface of the opening of the valve body and the opening on the protective clothing.
8. The all-plastic diaphragm type one-way exhaust check valve with emergency ventilation function as claimed in claim 1, wherein the first valve plate is an elastic plastic sheet, and the exhaust crack is cross-shaped.
9. The all-plastic membrane type one-way exhaust check valve with the emergency ventilation function as claimed in claim 1, wherein a gap is left between the first valve plate and the dome portion.
10. The all-plastic membrane type one-way exhaust check valve with emergency ventilation function as claimed in claim 9, wherein the first valve plate is closely attached to the support plate to form a first sealing surface from the outer side to the inner side of the protective clothing, and the second valve plate forms a second sealing surface with the exhaust port of the outer fastening fastener.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910260031.3A CN110145620B (en) | 2019-04-02 | 2019-04-02 | Full-plastic diaphragm type one-way exhaust check valve with emergency ventilation function |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910260031.3A CN110145620B (en) | 2019-04-02 | 2019-04-02 | Full-plastic diaphragm type one-way exhaust check valve with emergency ventilation function |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110145620A CN110145620A (en) | 2019-08-20 |
| CN110145620B true CN110145620B (en) | 2020-09-04 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910260031.3A Active CN110145620B (en) | 2019-04-02 | 2019-04-02 | Full-plastic diaphragm type one-way exhaust check valve with emergency ventilation function |
Country Status (1)
| Country | Link |
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| CN (1) | CN110145620B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111743579B (en) * | 2020-07-07 | 2023-05-30 | 德阳市人民医院 | Infectious department protection type pathogen sample collection device |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2715152A1 (en) * | 1976-08-06 | 1978-10-19 | Kern & Grosskinsky | Gas-tight clothing relief valve - has collar enclosing protective cap and shielding discharge slots |
| DE502004004668D1 (en) * | 2004-10-15 | 2007-09-27 | Moldex Metric Ag & Co Kg | Respirator with exhalation valve |
| JP6351137B2 (en) * | 2013-02-21 | 2018-07-04 | 株式会社重松製作所 | Respiratory protection |
| CN105682750B (en) * | 2013-08-27 | 2019-03-01 | 霍尼韦尔国际公司 | Use the fresh air mouth mechanism of the mask on self contained open loop compressed air breathing apparatus |
| CN204181009U (en) * | 2014-04-14 | 2015-03-04 | 左国刚 | A kind of self-cleaning Respiration assistance cleaning system and mouth mask and medicine applicator through nose |
| CN208058036U (en) * | 2018-03-27 | 2018-11-06 | 厦门智赫科技有限公司 | A kind of one-way exhausting device |
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2019
- 2019-04-02 CN CN201910260031.3A patent/CN110145620B/en active Active
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| CN110145620A (en) | 2019-08-20 |
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