CN103291979A - Backflow preventing device with low opening pressure, low flow resistance and reliable check - Google Patents
Backflow preventing device with low opening pressure, low flow resistance and reliable check Download PDFInfo
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- CN103291979A CN103291979A CN2012100476748A CN201210047674A CN103291979A CN 103291979 A CN103291979 A CN 103291979A CN 2012100476748 A CN2012100476748 A CN 2012100476748A CN 201210047674 A CN201210047674 A CN 201210047674A CN 103291979 A CN103291979 A CN 103291979A
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Abstract
The invention discloses a backflow preventing device with low opening pressure, low flow resistance and reliable check. The backflow preventing device comprises a water inlet check valve, a water outlet check valve and a discharge valve, wherein the water inlet check valve and the water outlet check valve divide the backflow preventing device into a water inlet cavity, a middle cavity and a water outlet cavity; a first rubber diaphragm movably covers a first valve port between the water inlet cavity and the middle cavity through a water inlet spring, and isolates the water inlet cavity and the middle cavity; and in the state that an acting force F1 which is generated by multiplying an area S1 of the first rubber diaphragm in the outer ring water inlet cavity of the first valve port by water inlet pressure intensity P1 is larger than an acting force F3 of the water inlet spring on the first rubber diaphragm, the first rubber diaphragm is away from the first valve port, the water inlet cavity is communicated with the middle cavity, and the valve port of the water inlet check valve is open. The backflow preventing device has the characteristics of low opening pressure, low flow resistance and reliable check, the influence on water pressure of a terminal user is extremely small, water pressure of a specified outdoor fire hydrant outlet is met, and easily-damaged parts can be convenient to replace.
Description
Technical field
The present invention relates to control the waterpower control gear that fluid in the pipeline can only one-way flow, relate in particular to the backflow preventer of used low cracking pressure on a kind of tap water pipeline, low flow resistance, reliable non-return.
Background technique
The water pipeline must be installed backflow preventer to the terminal use abroad, and the water in the strict restriction conduit can only one-way flow, prevents the pipeline backflow pollution, and is also carrying out successively in China city.Backflow preventer belongs to the isolated plant of protection tap water main pipe water supply quality, is installed on the tap water pipeline before the terminal use, if terminal use's hydraulic pressure is higher than water feeding pressure when taking place, can prevent that terminal use's aqueous reflux from returning main pipe.
Backflow preventer divides two kinds: decompression type and low-drag type.The decompression type: it is effective to prevent from flowing backwards, but loss of head is bigger, and terminal use's water is had a strong impact on; Low-drag type: almost the same with the decompression type, just lower spring rate, initial opening pressure reduces like this, and standard is 7KPa at present.These two kinds of backflow preventers all are to adopt two conventional one-way valves, and its maximum defective is the center that flap is placed in pipeline fluid, and spring is arranged behind the flap, and flap unlatching displacement is more big, and acting force of the spring is more big, and flap and spring are the obstacles that fluid flows.Therefore present backflow preventer flow resistance both domestic and external is relatively big, if do not change original structure, it almost is impossible lowering flow resistance.
At present both at home and abroad the water inlet safety check of used backflow preventer and to go out Water Check Valve all are conventional one-way valves is mounted valves in pipeline, and pipeline internal medium does not flow or upstream pressure is lower than authorized pressure following time, utilizes pressing force of the spring to make valve closing.Under unlatching or the big flow, this spring has become the obstacle of normal water supply with valve.How to reduce backflow preventer hydraulic losses problem bigger than normal, be global problem so far always.
Summary of the invention
The present invention is exactly the backflow preventer that a kind of low cracking pressure, low flow resistance, reliable non-return are provided for the problem that flow resistance is relatively large, hydraulic losses is bigger than normal that solves above-mentioned existing backflow preventer existence.
Purpose of the present invention is achieved through the following technical solutions:
The backflow preventer of a kind of low cracking pressure, low flow resistance, reliable non-return, comprise into the water safety check, go out Water Check Valve and drain valve, described water inlet safety check and go out Water Check Valve backflow preventer is divided into water-inlet cavity, intermediate cavity and water chamber, first elastomer diaphragm covers first valve port between water-inlet cavity and the intermediate cavity by water inlet spring activity, isolates water-inlet cavity and intermediate cavity; The area S1 of described first elastomer diaphragm in the first valve port outer ring water-inlet cavity multiply by the into directed force F 1 of water pressure P1 generation, greater than intaking spring under the state of the directed force F 3 on first elastomer diaphragm, first elastomer diaphragm is away from first valve port, water-inlet cavity and intermediate cavity UNICOM, water inlet safety check valve port is opened.
Preferably, described influent pressure is pretended on the gross area that is used in described first elastomer diaphragm under the state that water inlet safety check valve port is opened, and the active force that produce this moment is far longer than the into whole active forces of opening of water spring, and described water inlet safety check is all opened.
Preferably, the area S1 of described first elastomer diaphragm in the first valve port outer ring water-inlet cavity is 2 times of area S3 in the first valve port inner ring intermediate cavity, and the seal pressure that produces is 5 times of water pressure P1 into.
Preferably, described water inlet safety check comprises first valve body, first valve gap, first elastomer diaphragm, the first guide and limit bar and water inlet spring; Described first valve body is connected with first valve gap by bolt, press between first valve body and first valve gap and put first elastomer diaphragm, first elastomer diaphragm is connected to first valve gap by the water inlet spring, establish first guide and limit bar constraint water inlet spring in first valve gap, the other end of the first guide and limit bar is connected with first elastomer diaphragm.
Preferably, the runner of described water inlet safety check first valve body entrance to the first valve port is set to ramp structure.
Preferably, there are the tilt angle in described water inlet safety check first valve body and sprue water inlet, water outlet direction, the angle ranging from the 30-60 degree.
Preferably, separate with one second elastomer diaphragm between described intermediate cavity and the water chamber, described second elastomer diaphragm covers second valve port between intermediate cavity and the water chamber by the activity of water outlet spring, the area S2 of second elastomer diaphragm in the second valve port outer ring intermediate cavity multiply by the directed force F 2 that fluid pressure P2 produces, greater than the water outlet spring under the state of the directed force F 4 on second elastomer diaphragm, second elastomer diaphragm is away from second valve port, intermediate cavity and water chamber UNICOM go out the Water Check Valve valve port and open.
Preferably, the area S2 of described second elastomer diaphragm in the second valve port outer ring intermediate cavity is 1.2 times of area S4 in the second valve port inner ring water chamber, and the seal pressure that produces is 5 times of fluid pressure P2.
Preferably, the described water inlet safety check runner that is exported to out Water Check Valve second valve port is set to ramp structure.
Preferably, describedly go out Water Check Valve and comprise second valve body, second valve gap, second elastomer diaphragm, the second guide and limit bar and water outlet spring; Described second valve body is connected with second valve gap by bolt, press between second valve body and second valve gap and put second elastomer diaphragm, second elastomer diaphragm is connected to second valve gap by the water outlet spring, establish second guide and limit bar constraint water outlet spring in second valve gap, the other end of the second guide and limit bar is connected with second elastomer diaphragm.
Compared with prior art, the present invention has following beneficial effect:
The present invention has the characteristics of low cracking pressure, low flow resistance, reliable non-return, and is minimum to terminal use's water influence of hydraulic pressure, satisfy the Outdoor Fire Hydrant outlet hydraulic pressure of regulation, and it is convenient to change easily damaged parts.
Description of drawings
Fig. 1 is the structural representation of backflow preventer closed condition;
Fig. 2 is the structural representation of backflow preventer opening state.
Embodiment
Describe the present invention in detail below in conjunction with accompanying drawing.
Referring to Fig. 1, Fig. 2, the backflow preventer of low cracking pressure of the present invention, low flow resistance, reliable non-return comprises into the water safety check at least, goes out Water Check Valve and drain valve, but changed water inlet safety check, the structure that goes out Water Check Valve, working method and mounting point, and flap is not on runner.
Water inlet safety check 100 comprises first valve body 11, first valve gap 12, first elastomer diaphragm 13, the first guide and limit bar 14 and water inlet spring 15; First valve body 11 is connected with first valve gap 12 by bolt, press between first valve body 11 and first valve gap 12 and put first elastomer diaphragm 13, first elastomer diaphragm 13 is connected to first valve gap 12 by water inlet spring 15, the other end of establishing the first guide and limit bar, 14 constraint water inlet springs, 15, the first guide and limit bars 14 in first valve gap 12 is connected with first elastomer diaphragm 13.Go out Water Check Valve 200 and comprise second valve body 21, second valve gap 22, second elastomer diaphragm 23, the second guide and limit bar 24 and water outlet spring 25; Second valve body 21 is connected with second valve gap 22 by bolt, press between second valve body 21 and second valve gap 22 and put second elastomer diaphragm 23, second elastomer diaphragm 23 is connected to second valve gap 22 by water outlet spring 25, the other end of establishing the second guide and limit bar, 24 constraint water outlet springs, 25, the second guide and limit bars 24 in second valve gap 22 is connected with second elastomer diaphragm 23.Filter screen is not represented at this.
Water inlet safety check 100 and go out Water Check Valve 200 UNICOM that is connected in series, backflow preventer is divided into water-inlet cavity, intermediate cavity and water chamber, first elastomer diaphragm 13 covers on the first valve port A1 between water-inlet cavity and the intermediate cavity by water inlet spring 15 activities, isolates water-inlet cavity and intermediate cavity; Second elastomer diaphragm 23 covers on the second valve port A2 between intermediate cavity and the water chamber by 25 activities of water outlet spring, separates intermediate cavity and water chamber.
The area S1 of first elastomer diaphragm 13 in the first valve port A1 outer ring water-inlet cavity multiply by the directed force F 1 that the water inlet pressure P1 in the water-inlet cavity produces, greater than intaking spring 15 under the state of the directed force F 3 on first elastomer diaphragm 13, first elastomer diaphragm 13 is away from the first valve port A1, water-inlet cavity and intermediate cavity UNICOM, water inlet safety check valve port is opened.
Under the state that water inlet safety check valve port is opened, influent pressure is pretended on the gross area that is used in first elastomer diaphragm 13, and the active force that produce this moment is far longer than into water spring 15 whole active forces of opening, and the water inlet safety check is all opened.
Go out the Water Check Valve working principle and be equal to into water safety check, the area S2 of second elastomer diaphragm 23 in the second valve port A2 outer ring intermediate cavity multiply by the directed force F 2 that fluid pressure P2 produces, greater than water outlet spring 25 under the state of the directed force F 4 on second elastomer diaphragm 23, second elastomer diaphragm 23 is away from the second valve port A2, intermediate cavity and water chamber UNICOM go out the Water Check Valve valve port and open.Be lower than the into unlatching hydraulic pressure of water safety check owing to go out the unlatching hydraulic pressure of Water Check Valve, so the rigidity of water outlet spring 25 is lower than into water spring 15.
The effect of elastomer diaphragm of the present invention has three, one, advances the isolation diaphragm of water and water outlet, and the 2nd, advance the sensing element of water and water outlet two hydraulic pressure, the 3rd, the valve sealing element of safety check.For obtaining effect preferably, the runner of water inlet safety check first valve body 11 entrance to the first valve port A1, the water inlet safety check is exported to out the runner of the Water Check Valve second valve port A2, all be set to ramp structure, utilizing among inclined-plane a1, a2(Fig. 1,2 shown in the dotted line) the guiding fluid flows, and reduces the flow resistance that fluid produces because of eddy current in valve body.Water inlet safety check first valve body 11, go out Water Check Valve second valve body 21 and have the tilt angle with sprue water inlet, water outlet direction, the angle ranging from the 30-60 degree, preferred 45 degree.
The concrete working procedure of this backflow preventer is described in detail as follows:
The flap of water inlet safety check is first elastomer diaphragm 13, and fluid is directed on first elastomer diaphragm of the water safety check first valve port A1 outer ring into by inclined-plane, the outer ring a1 of water inlet safety check first valve body 11 by the direction of arrow shown in Figure 1.
When water feeding pressure was lower than the design load of water safety check into, because the water inlet spring action, first elastomer diaphragm 13 kept sealing with the first valve port A1, the closure of check ring of intaking.When water feeding pressure greater than the water inlet safety check design load the time, water feeding pressure P1 acts on first elastomer diaphragm 13 of the first valve port A1 outer ring, the directed force F 1 of its generation is greater than the directed force F 3 of water inlet spring 15, first elastomer diaphragm 13 overcomes its initial sealing force, away from the first valve port A1, the valve port of water inlet safety check is opened.Fluid enters inner ring by the outer ring of water inlet safety check first valve body, and fluid pressure herein is P2.In case open, water feeding pressure acts on the gross area of first elastomer diaphragm, as long as act on hydraulic pressure P1 and the P2 on the first elastomer diaphragm two sides micro-pressure reduction is arranged, the active force that its pressure reduction produces overcomes the into full open power of water spring fully, water inlet safety check standard-sized sheet.
The flap that goes out Water Check Valve is second elastomer diaphragm 23, and the fluid of inner ring is directed to out on the elastomer diaphragm of the Water Check Valve second valve port A2 outer ring by inclined-plane, the outer ring a2 that goes out Water Check Valve.
In like manner, go out the requirement of Water Check Valve opened by pressure according to standard, P2 acts on out on second elastomer diaphragm 23 of the Water Check Valve second valve port A2 outer ring, the directed force F 2 of its generation is greater than the directed force F 4 of water outlet spring 25, second elastomer diaphragm 23 overcomes the initial sealing force of water outlet spring 25, separates with the second valve port A2 that goes out Water Check Valve.Fluid enters inner ring by the outer ring that goes out Water Check Valve second valve body, and fluid pressure herein is P3.In case second elastomer diaphragm with go out the Water Check Valve second valve port A2 and separate, fluid pressure acts on the gross area of second elastomer diaphragm, as long as act on hydraulic pressure P2 and the P3 on the second elastomer diaphragm two sides micro-pressure reduction is arranged, the active force that its pressure reduction produces overcomes the full open power of water outlet spring fully, goes out the Water Check Valve standard-sized sheet.Fig. 2 is the structural representation of backflow preventer full open state.
Water is few when the downstream of backflow preventer, flow is low, or water feeding pressure P1 equates with water outlet hydraulic pressure P3, because the effect of water inlet spring (or water outlet spring), the first valve port A1 second valve port A2 of Water Check Valve (or go out) of first (or second) elastomer diaphragm and the water inlet safety check sealing of fitting, water inlet safety check and water outlet closure of check ring.When the backflow preventer downstream pressure is higher than upstream pressure, water outlet hydraulic pressure is greater than water feeding pressure, and the sealing force that acts on the elastomer diaphragm strengthens, and the sealing at this place is more reliable.Destroy elastomer diaphragm in order to prevent that sealing force is excessive, the first/the second guide and limit bar has limited the excessive deformation of the first/the second elastomer diaphragm, plays a protective role.
Water inlet safety check and the design that goes out Water Check Valve:
The water inlet safety check, going out Water Check Valve can open under the hydraulic pressure of regulation reliably, fluid pressure acts on the elastomer diaphragm, elastomer diaphragm is not subjected to the restriction of physical dimension, can change fluid pressure and act on area on the elastomer diaphragm according to opening requirement, make the little initial sealing power greater than water inlet spring (or water outlet spring) of active force of its generation, elastomer diaphragm is opened, in case open, the area that fluid pressure acts on the elastomer diaphragm is changed into gross area by original local area, Ci Shi fluid pressure is lower than initial fluid pressure on the contrary as calculated, just can make elastomer diaphragm be in the full open state.Be example with the backflow preventer that designs 100 internal diameters, water inlet safety check: cracking pressure 8KPa, full open pressure reduction 6KPa; Go out Water Check Valve: cracking pressure 4KPa, full open pressure reduction 2.5KPa.
Therefore as requested, the area of first elastomer diaphragm and second elastomer diaphragm initially can be given arbitrarily in design, is not subjected to the restriction of Flow diameter.In like manner, cracking pressure initially can be given arbitrarily in design.
Fluid enters inner ring by (water inlet safety check, go out Water Check Valve) valve body outer ring by the first valve port A1 or the second valve port A2, and the area of outer ring can change according to demand, and the inner ring area is to import and export required areas, also can require to adjust according to flow resistance.After the area of inner ring and outer ring was adjusted, designing and calculating its water inlet spring or water outlet spring just can reach the design objective requirement.Preferably, the area S1 of first elastomer diaphragm in the first valve port outer ring water-inlet cavity is 2 times of area S3 in the first valve port inner ring intermediate cavity, and the seal pressure that produces is 5 times of water pressure P1 into.The area S2 of second elastomer diaphragm in the second valve port outer ring intermediate cavity is 1.2 times of area S4 in the second valve port inner ring water chamber, and the seal pressure that produces is 5 times of fluid pressure P2.
Water inlet spring on the elastomer diaphragm (or water outlet spring) is given as requested, because structural feature, can Redundancy Design, and improve seal pressure, therefore can improve the up-to-standard rate of batch process.The water inlet safety check is separated with the sprue that goes out Water Check Valve mounting point and water, has overcome the flap of conventional safety check and the problem on obstacle that spring is water flow passage fully.
More than disclosed only be several specific embodiments of the application, but the application is not limited thereto, any those skilled in the art can think variation, all should drop in the application's the protection domain.
Claims (10)
1. the backflow preventer of a low cracking pressure, low flow resistance, reliable non-return, comprise into the water safety check, go out Water Check Valve and drain valve, it is characterized in that, described water inlet safety check and go out Water Check Valve backflow preventer is divided into water-inlet cavity, intermediate cavity and water chamber, first elastomer diaphragm covers first valve port between water-inlet cavity and the intermediate cavity by water inlet spring activity, isolates water-inlet cavity and intermediate cavity; The area S1 of described first elastomer diaphragm in the first valve port outer ring water-inlet cavity multiply by the into directed force F 1 of water pressure P1 generation, greater than intaking spring under the state of the directed force F 3 on first elastomer diaphragm, first elastomer diaphragm is away from first valve port, water-inlet cavity and intermediate cavity UNICOM, water inlet safety check valve port is opened.
2. the backflow preventer of low cracking pressure as claimed in claim 1, low flow resistance, reliable non-return, it is characterized in that, described under the state that water inlet safety check valve port is opened, influent pressure is pretended on the gross area that is used in described first elastomer diaphragm, the active force that produce this moment is far longer than the into whole active forces of opening of water spring, and described water inlet safety check is all opened.
3. the backflow preventer of low cracking pressure as claimed in claim 1, low flow resistance, reliable non-return, it is characterized in that, the area S1 of described first elastomer diaphragm in the first valve port outer ring water-inlet cavity is 2 times of area S3 in the first valve port inner ring intermediate cavity, and the seal pressure that produces is 5 times of water pressure P1 into.
4. the backflow preventer of low cracking pressure as claimed in claim 1, low flow resistance, reliable non-return is characterized in that, described water inlet safety check comprises first valve body, first valve gap, first elastomer diaphragm, the first guide and limit bar and water inlet spring; Described first valve body is connected with first valve gap by bolt, press between first valve body and first valve gap and put first elastomer diaphragm, first elastomer diaphragm is connected to first valve gap by the water inlet spring, establish first guide and limit bar constraint water inlet spring in first valve gap, the other end of the first guide and limit bar is connected with first elastomer diaphragm.
5. the backflow preventer of low cracking pressure as claimed in claim 4, low flow resistance, reliable non-return is characterized in that the runner of described water inlet safety check first valve body entrance to the first valve port is set to ramp structure.
6. the backflow preventer of low cracking pressure as claimed in claim 4, low flow resistance, reliable non-return is characterized in that, there are the tilt angle in described water inlet safety check first valve body and sprue water inlet, water outlet direction, the angle ranging from the 30-60 degree.
7. low cracking pressure as claimed in claim 1, low flow resistance, the backflow preventer of reliable non-return, it is characterized in that, separate with one second elastomer diaphragm between described intermediate cavity and the water chamber, described second elastomer diaphragm covers second valve port between intermediate cavity and the water chamber by the activity of water outlet spring, the area S2 of second elastomer diaphragm in the second valve port outer ring intermediate cavity multiply by the directed force F 2 that fluid pressure P2 produces, greater than the water outlet spring under the state of the directed force F 4 on second elastomer diaphragm, second elastomer diaphragm is away from second valve port, intermediate cavity and water chamber UNICOM go out the Water Check Valve valve port and open.
8. the backflow preventer of low cracking pressure as claimed in claim 7, low flow resistance, reliable non-return, it is characterized in that, the area S2 of described second elastomer diaphragm in the second valve port outer ring intermediate cavity is 1.2 times of area S4 in the second valve port inner ring water chamber, and the seal pressure that produces is 5 times of fluid pressure P2.
9. the backflow preventer of low cracking pressure as claimed in claim 7, low flow resistance, reliable non-return is characterized in that the runner that described water inlet safety check is exported to out Water Check Valve second valve port is set to ramp structure.
10. as the backflow preventer of claim 1 or 7 described low cracking pressures, low flow resistance, reliable non-return, it is characterized in that, describedly go out Water Check Valve and comprise second valve body, second valve gap, second elastomer diaphragm, the second guide and limit bar and water outlet spring; Described second valve body is connected with second valve gap by bolt, press between second valve body and second valve gap and put second elastomer diaphragm, second elastomer diaphragm is connected to second valve gap by the water outlet spring, establish second guide and limit bar constraint water outlet spring in second valve gap, the other end of the second guide and limit bar is connected with second elastomer diaphragm.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210047674.8A CN103291979B (en) | 2012-02-28 | 2012-02-28 | The backflow preventer of low cracking pressure, low flow resistance, reliable non-return |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210047674.8A CN103291979B (en) | 2012-02-28 | 2012-02-28 | The backflow preventer of low cracking pressure, low flow resistance, reliable non-return |
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| Publication Number | Publication Date |
|---|---|
| CN103291979A true CN103291979A (en) | 2013-09-11 |
| CN103291979B CN103291979B (en) | 2016-04-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201210047674.8A Active CN103291979B (en) | 2012-02-28 | 2012-02-28 | The backflow preventer of low cracking pressure, low flow resistance, reliable non-return |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106015630A (en) * | 2016-07-05 | 2016-10-12 | 武汉长光电源有限公司 | Improved lead valve |
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2012
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| EP0235766A2 (en) * | 1986-03-03 | 1987-09-09 | AWECO Kunststofftechnik Gerätebau GmbH & Co. KG | Safety valve for household appliances |
| JP2832575B2 (en) * | 1994-02-10 | 1998-12-09 | 株式会社東京暖冷器製作所 | Gate valve |
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| CN106015630A (en) * | 2016-07-05 | 2016-10-12 | 武汉长光电源有限公司 | Improved lead valve |
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| CN103291979B (en) | 2016-04-20 |
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