CN103821969A - Follow-up backflow preventer - Google Patents
Follow-up backflow preventer Download PDFInfo
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- CN103821969A CN103821969A CN201410042043.6A CN201410042043A CN103821969A CN 103821969 A CN103821969 A CN 103821969A CN 201410042043 A CN201410042043 A CN 201410042043A CN 103821969 A CN103821969 A CN 103821969A
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- barrier film
- water
- soft barrier
- valve
- safety check
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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
- F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
- F16K11/10—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with two or more closure members not moving as a unit
- F16K11/105—Three-way check or safety valves with two or more closure members
-
- 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
- F16K17/00—Safety valves; Equalising valves, e.g. pressure relief valves
- F16K17/02—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side
- F16K17/12—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side weight-loaded
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- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Check Valves (AREA)
Abstract
The invention discloses a follow-up backflow preventer which is a place used for strictly allowing pressure water in a pipeline to unidirectionally flow. The follow-up backflow preventer is mainly composed of a valve body (1), a gravity-type check valve I (2), a gravity-type check valve II (5) and a pressure difference drain valve (8), and the valve body (1) is mainly composed of a water incoming cavity (12), a valve cavity (13), a water outgoing cavity (14), a back pressure cavity I (15), a back pressure cavity II (16), a positive pressure cavity (17), a drain valve cavity (18) and a dewatering cavity (20). Compared with the prior art, the follow-up backflow preventer has the advantages that water flow resistance is greatly reduced, and waterhead loss is allowed to be lowered below 0.015Mpa from 0.1Mpa.
Description
Technical field
The present invention relates to a kind of backflow preventer, specifically a kind of for the strict lower resistance follow-up type backflow preventer that limits the place that ducted press water can only one-way flow.
Background technique
Municipal water supply pipe network extensively adopts backflow preventer, to prevent that the refluence water that user produces in water utilizing process from entering in pipe network again, avoids contamination accident, guarantees the safe and sanitary that supplies water.According to code requirement, the split point of city planting ductwork and user's access place, different system and different water water quality, backflow preventer all should be installed, but the permission loss of head of backflow preventer is generally at 0.05MPa even more than 0.1MPa, obviously increase the water supply power consumption of city planting ductwork and the water leakage ratio of pipe network, caused very large waste.Consider for energy-saving and cost-reducing, current domestic municipal water supply pipe network takes backflow preventer mixed with safety check, in same pipe network, take " dual " safety standard, both performances are not completely on same class, the Safety performance of safety check is far below backflow preventer, and water supply safe and sanitary can fundamentally not be protected.
The resistance of backflow preventer is from two aspects, and the one, the stiction that the gravity of movable part itself or elastic force bring, the 2nd, pipelined channel produces the dynamic resistance that turbulent flow brings.The shortcoming that the large energy consumption of existing backflow preventer resistance is high is mainly to set up due to the spring structure of ladder pressure reduction, both cannot eliminate the elastic resistance that even reduces spring, also be difficult for by flow passage components are carried out to correction of the flank shape in the hope of reducing turbulent loss, and elastic resistance strengthens with flow, from its technical development process, can find out, the standard that backflow preventer is carried out develops into city-building product industry standard (CJ/T160-2010) from city-building industry standard (CJ/T160-2002), arrive again NBS (GB/T25178-2010), and nearest machinery industry standard (JB/T11151-2011), object is wherein not in order to improve Safety performance, but do one's utmost to reduce loss of head, but due to the spring structure of inheriting tradition, drag reduction way is to rely on to reduce security parameter substantially, fail to eliminate the elastic resistance of spring, allow loss of head still to maintain 0.06Mpa above high-order, effect is unsatisfactory, evolution has also proved on the basis of prior art thinking, to be difficult to improve and break through, the high greatest drawback that becomes prior art of the large energy consumption of resistance.
Summary of the invention
In order to overcome the deficiencies in the prior art, the invention provides a kind of follow-up type backflow preventer of lower resistance.
The technological scheme that the present invention solves the problems of the technologies described above is:
A kind of follow-up type backflow preventer, it is characterized in that, formed by valve body 1, gravity type safety check 1, valve rod 1, soft barrier film 1, gravity type safety check 25, valve rod 26, soft barrier film 27, pressure reduction drain valve 8, valve rod 39, soft barrier film 3 10, soft barrier film 4 11, positive pressure tube 21, back pressure pipe 22 and breathing pipe 23.
The valve body 1 of described follow-up type backflow preventer is made up of water-inlet cavity 12, valve pocket 13, water chamber 14, back pressure cavity 1, back pressure cavity 2 16, malleation chamber 17, sluicing valve pocket 18 and drain chamber 20.
Described follow-up type backflow preventer, turnover current press in water cavity 12, valve pocket 13, water chamber 14 order circulations.
Described follow-up type backflow preventer, between water-inlet cavity 12 and valve pocket 13, establish gravity type safety check 1, between valve pocket 13 and water chamber 14, establish gravity type safety check 25, between valve pocket 13 and back pressure cavity 1, establish soft barrier film 1, between water chamber 14 and back pressure cavity 2 16, establish soft barrier film 27, between sluicing valve pocket 18 and water chamber 14, establish soft barrier film 3 10, between sluicing valve pocket 18 and drain chamber 20, establish pressure reduction drain valve 8, between malleation chamber 17 and drain chamber 20, establish soft barrier film 4 11, between sluicing valve pocket 18 and valve pocket 13, establishing hole 19 is communicated with, water-inlet cavity 12 is communicated with malleation chamber 17 by positive pressure tube 21, back pressure cavity 1 interconnects by back pressure pipe 22 and water chamber 14 with back pressure cavity 2 16, the mouth of pipe of back pressure pipe 22 in water chamber 14 with water outlet direction forward, the opening direction of gravity type safety check 1 and gravity type safety check 25 and water outlet direction are forward.
The valve rod of described follow-up type backflow preventer connects respectively soft barrier film 1 and gravity type safety check 1 in two ends Shang Xia one 3, the two ends up and down of valve rod 26 connect respectively soft barrier film 27 and gravity type safety check 25, the two ends up and down of valve rod 39 connect respectively soft barrier film 3 10 and soft barrier film 4 11, and pressure reduction drain valve 8 is fixed on valve rod 39 between soft barrier film 3 10 and soft barrier film 4 11.
The soft barrier film 1 of described follow-up type backflow preventer, is made up of the soft barrier film of separable bilayer, and double-deck soft barrier film can be expanded the space airtight for inside, and the inner breathing pipe 23 that passes through is communicated with atmosphere.
The present invention's feature is compared with the prior art:
1. adopt non-spring structure, thoroughly eliminate the elastic resistance of spring component.
2. utilize self loss of head and water flow dynamic energy and potential energy to change mutually the differential pressure action power of generation, this active force produces because of hydrodynamic(al), and water is quiet and disappear, be directly proportional to the flow velocity size of water, in order to reduce until eliminate the resistance that movable part self gravitation brings.
3. utilize the interaction of differential water pressures and gravity, ladder pressure reduction was set up in quiet moment of moving of current, and quiet, to moving moment elimination, initiative realizes the dreamboat of " by quiet vertical, moving disappears ".
4. pipelined channel net area is larger, and flow velocity is lower, and turbulent loss is less.
5. properties constant, performance parameter can not change with service time, has overcome the spring structure drawback that performance progressively declines with increasing service time.
Outstanding advantages of the present invention is greatly to reduce resistance, prior art, though traditional spring structure provides the power of closing, but unavoidably intactly become unlatching resistance, the loss of head that spring structure produces accounts for the more than 70% of backflow preventer gross head loss, the negative effect of visible spring is very large, and prior art reduces loss of head way to reduce security parameter is difficult to prove that Safety performance is not lowered, and resistance reducing effect is unsatisfactory.It is considered herein that, the work characteristics of backflow preventer is that " valve is with hydrodynamic(al), water stops with valve ", ladder pressure reduction must be in the time that current will stop moment setting up, this does not have different from the safety requirement of existing standard, once but the mobile possibility that does not have refluence of water, ladder pressure reduction is unnecessary, can become on the contrary the resistance that hinders current, when fixing on water flow, existing master gage still must keep very large ladder pressure reduction, be security needs, not equal to be the back heavy " elastic force burden " of having to, real in having no way out, the meaning of regulation is only to show rational existence like this, not desirability, therefore lack scientific, unavoidably there is the suspicion that hinders technological innovation development, more unnecessarily as mandatory technical requirements.In fact, reduce the target that loss of head is this field unremitting pursue always, the size of resistance has become unique yardstick of weighing backflow preventer performance quality.
The present invention has abandoned traditional " elastic force burden " completely, be not less than in Safety performance under the prerequisite of existing standard, allow loss of head to be reduced to above 0.015MPa even below 0.01MPa by the 0.1MPa of same category of device, suitable with Swing check valve, can realize perfect unity energy-saving and cost-reducing and safety water supply, establish technical foundation for " dual " standard of cancelling pipe network, can eliminate the high prior art of the large energy consumption of resistance completely, the standard of establishing backflow preventer of new generation.
Accompanying drawing is described
Structural representation when Fig. 1 is circulation status of the present invention.
Structural representation when Fig. 2 is closed condition of the present invention.
Structural representation when Fig. 3 is the too low state of hydraulic pressure of the present invention.
Structural representation when Fig. 4 is hull-borne of the present invention.
In Fig. 1～Fig. 4: valve body 1, gravity type safety check 1, valve rod 1, soft barrier film 1, gravity type safety check 25, valve rod 26, soft barrier film 27, pressure reduction drain valve 8, valve rod 39, soft barrier film 3 10, soft barrier film 4 11, water-inlet cavity 12, valve pocket 13, water chamber 14, back pressure cavity 1, back pressure cavity 2 16, malleation chamber 17, sluicing valve pocket 18, hole 19, drain chamber 20, positive pressure tube 21, back pressure pipe 22, breathing pipe 23.
Embodiment
Below in conjunction with accompanying drawing, the invention will be further described.
One, workflow
Workflow of the present invention is divided into circulation operating mode, closes operating mode, low hydraulic pressure operating mode, draining operating mode and reset operating mode, is described below:
1. circulation operating mode
As shown in Figure 1: when water-inlet cavity 12 hydraulic pressure open hydraulic pressure higher than setting value, the active force of water is greater than the gravity of gravity type safety check 1 and gravity type safety check 25, gravity type safety check 1 is fully opened in succession with gravity type safety check 25, and water is able to circulate smoothly to water chamber 14 through water-inlet cavity 12, valve pocket 13.When water flow, the flow process of back pressure pipe 22 mouths of pipe in from water-inlet cavity 12 to water chamber 14, be that potential energy produces differential water pressures by the kinetic transformation of loss of head and water, the larger differential water pressures of water velocity is just larger, this pressure reduction enters in back pressure cavity 1 and back pressure cavity 2 16 by back pressure pipe 22, act on respectively on soft barrier film 1 and soft barrier film 27, the active force producing is progressively offset respectively the gravity (weight with valve rod 26 containing valve rod 1 respectively) of gravity type safety check 1 and gravity type safety check 25, thereby reduces until eliminate the loss of head being brought by gravity; Simultaneously, this pressure reduction is entered in malleation chamber 17 and is acted on soft barrier film 4 11 by positive pressure tube 21, and enter in sluicing valve pocket 18 and act on soft barrier film 3 10 by hole 19, the active force producing is always greater than the gravity (containing the weight of valve rod 3 9) of pressure reduction drain valve 8, pressure reduction drain valve 8 is closed, and water can not be discharged from drain chamber 20 through sluicing valve pocket 18; Meanwhile, because hydraulic pressure is greater than air pressure, atmosphere can not enter soft barrier film one 4 interior expansions from breathing pipe 23.
2. close operating mode
As shown in Figure 2: water-inlet cavity 12 hydraulic pressure are higher than opening hydraulic pressure, water velocity slows down until stop flowing, above-mentioned differential water pressures reduces thereupon gradually, active force is corresponding to be reduced, in the time being less than gravity, gravity type safety check 1 and gravity type safety check 25 are at each self closing, water can not circulate, now water-inlet cavity 12, valve pocket 13 forms three hydraulic pressure ladders from high to low in order with the hydraulic pressure in water chamber 14, between step, all having certain differential water pressures is ladder pressure reduction, pollute to guarantee that water can not occur to flow backwards, as long as keep stable ladder pressure reduction between in each chamber, the active force acting on pressure reduction drain valve 8 valve plates is always greater than its gravity, order about pressure reduction drain valve 8 and keep closed condition.
3. low hydraulic pressure operating mode
As shown in Figure 3: in the time that water-inlet cavity 12 hydraulic pressure drop to unlatching hydraulic pressure, gravity type safety check 1 cuts out automatically because gravity is greater than Water Pressure power, enters and closes operating mode, and now, under the effect of pressure reduction, atmosphere can enter the interior expansion of soft barrier film 1 by breathing pipe 23; In the time that water-inlet cavity 12 hydraulic pressure drop to sluicing pressure reduction, pressure reduction drain valve 8 is opened, and enters draining operating mode.
4. draining operating mode
As shown in Figure 4: in the time closing operating mode, because there is water pressure fluctuations or because of the generation seepage that is not closed completely in water-inlet cavity 12 and water chamber 14, above-mentioned ladder pressure reduction reduces, corresponding the reducing of active force that now differential pressure action produces on soft barrier film 3 10 and soft barrier film 4 11, can not offset the gravity of pressure reduction drain valve 8 time, pressure reduction drain valve 8 is opened and is sluiced, water in valve pocket 13 through hole 19, sluicing valve pocket 18, drain chamber 20 leak into atmosphere, atmosphere enters the interior formation air partition of valve pocket 13 through drain chamber 20, sluicing valve pocket 18 with hole 19 simultaneously.
5. reset operating mode
As shown in Figure 1: water-inlet cavity 12 hydraulic pressure again rise and are greater than while opening hydraulic pressure, and current reopen gravity type safety check 1 and gravity type safety check 25 in succession, and operating mode circulates.
Two, computational methods
Calculating of the present invention is mainly according to definite unlatching hydraulic pressure, ladder pressure reduction and sluicing pressure reduction, calculates respectively the weight (containing respectively the weight of valve rod 1, valve rod 26 and valve rod 3 9) of gravity type safety check 1, gravity type safety check 25 and pressure reduction drain valve and the specification of soft barrier film 1, soft barrier film 27, soft barrier film 3 10 and soft barrier film 4 11.
Carry out following calculating Shi Xu effective unit.
1. open hydraulic pressure
Determine by standard (standard), in the time that water hydraulic pressure drops to unlatching hydraulic pressure, gravity type safety check 1 cuts out automatically, and now pressure reduction drain valve is failure to actuate.
2. ladder pressure reduction
Ladder pressure reduction should meet the following conditions
P
1-P
2≧C
1 （1）
P
2-P
3≧C
2 （2）
In formula: P
1the hydraulic pressure of-water-inlet cavity
P
2the hydraulic pressure of-valve pocket
P
3the hydraulic pressure of-water chamber
C
1when-zero delivery, the minimum permissible pressure of water-inlet cavity and valve pocket, opens hydraulic pressure, is 0.02MPa by GB/T25178-2010 standard, is 0.007MPa or 0.014MPa(high safety grade by JB/T11151-2011 standard)
C
2when-zero delivery, valve pocket 13 and the minimum permissible pressure of water chamber 14, be 0.007MPa by GB/T25178-2010 standard, is 0.0035MPa or 0.007MPa(high safety grade by JB/T11151-2011 standard)
Now pressure reduction drain valve 8 is failure to actuate.
3. sluicing pressure reduction
In dead head condition, because of water chamber 14 hydraulic pressure P
3rise or water-inlet cavity 12 hydraulic pressure P
1decline while causing pressure reduction drain valve 8 to start to sluice, should meet the following conditions
P
1-P
2≧C
3 （3）
In formula: C
3: the minimum sluicing pressure reduction that allows is 0.014MPa by GB/T25178-2010 standard, is C3=0 and 0.01MPa(high safety grade by JB/T11151-2011 standard)
When cutting out automatically, pressure reduction drain valve 8 should meet P
1-P
2≮ C
3.
4. gravity type safety check 1 and gravity type safety check 25
There is following relation with ladder pressure reduction respectively in both
W
1=C
1·S
1 （4）
W
2=C
2·S
2 （5）
In formula:
W
1, W
2: the weight of gravity type safety check 1, gravity type safety check 25.
S
1, S
2: the orifice area of gravity type safety check 1, gravity type safety check 25.
5. pressure reduction drain valve 8
While pressing GB/T25178-2010 standard, there is following relation with ladder pressure reduction
W
3=（C
1+C
2-⊿C）S
3 （6）
In formula:
W
3: the weight of pressure reduction drain valve 8.
S
3: the orifice area of pressure reduction drain valve 8, the i.e. useful area of soft barrier film 39 or soft barrier film 4 11.
⊿ C: gravity type safety check 1 is opened hydraulic pressure C
1open hydraulic pressure C with pressure reduction drain valve 8
3poor,
Ji ⊿ C=0.02-0.014=0.006MPa
While pressing JB/T11151-2011 standard, be
W
3=⊿C＇·S
3 （7）
: ⊿ C ＇ in formula: water-inlet cavity water 12 is pressed P
1with water chamber 14 hydraulic pressure P
3poor, high safety grade Shi ， ⊿ C ＇=0.01MPa; When non-high safety grade, ⊿ C ＇=0 is unrealistic, do not reduce Safety performance before put, ⊿ C ＇ can be between 0.001～0.01MPa value.
6. soft barrier film 1
There is following relation with ladder pressure reduction
S
4=S
1·C
1/C
2 （8）
In formula: S
4: the useful area of soft barrier film 1.
7. soft barrier film 27
According to backflow preventer exit velocity, there is following relation
S
5=2g·C
2·S
2/v
2 （9）
In formula: S
5: the useful area of soft barrier film 27.
G: gravity accleration.
V: the exit velocity of backflow preventer, between desirable 1～3m/s.
8. soft barrier film 37 and soft barrier film 4 11
Soft barrier film 37 is identical with the specification of soft barrier film 4 11, in the time that the weight of pressure reduction drain valve 8 is determined
S
3=W
3/（C
1+C
2-⊿C） （10）
Or
S
3=W
3/⊿C＇ （11）
Conclusion
Adopt " pressure reduction type backflow preventer " (GB/T25178-2010) when standard, permission loss of head of the present invention can be reduced to 0.015MPa by 0.1MPa; Adopt " low resistance force counter flow stop " (JB/T11151-2011) when standard, allow loss of head can be reduced to below 0.01MPa.
Claims (2)
1. a follow-up type backflow preventer, it is characterized in that, formed by valve body (1), gravity type safety check one (2), valve rod one (3), soft barrier film one (4), gravity type safety check two (5), valve rod two (6), soft barrier film two (7), pressure reduction drain valve (8), valve rod three (9), soft barrier film three (10), soft barrier film four (11), positive pressure tube (21), back pressure pipe (22) and breathing pipe (23);
The valve body (1) of described follow-up type backflow preventer is made up of water-inlet cavity (12), valve pocket (13), water chamber (14), back pressure cavity one (15), back pressure cavity two (16), malleation chamber (17), sluicing valve pocket (18) and drain chamber (20);
Described follow-up type backflow preventer, current are pressed water-inlet cavity (12), valve pocket (13), the circulation of water chamber (14) order;
Described follow-up type backflow preventer, between water-inlet cavity (12) and valve pocket (13), establish gravity type safety check one (2), between valve pocket (13) and water chamber (14), establish gravity type safety check two (5), between valve pocket (13) and back pressure cavity one (15), establish soft barrier film one (4), between water chamber (14) and back pressure cavity two (16), establish soft barrier film two (7), between sluicing valve pocket (18) and water chamber (14), establish soft barrier film three (10), between sluicing valve pocket (18) and drain chamber (20), establish pressure reduction drain valve (8), between malleation chamber (17) and drain chamber (20), establishing soft barrier film four (11) separates, between sluicing valve pocket (18) and valve pocket (13), establishing hole (19) is communicated with, water-inlet cavity (12) is communicated with malleation chamber (17) by positive pressure tube (21), back pressure cavity one (15) interconnects by back pressure pipe (22) and water chamber (14) with back pressure cavity two (16), the mouth of pipe direction of back pressure pipe (22) in water chamber (14) and water inlet direction are forward, the opening direction of gravity type safety check one (2) and gravity type safety check two (5) and water inlet direction are forward,
Described follow-up type backflow preventer, the two ends up and down of valve rod one (3) connect respectively soft barrier film one (4) and gravity type safety check one (2), the two ends up and down of valve rod two (6) connect respectively soft barrier film two (7) and gravity type safety check two (5), the two ends up and down of valve rod three (9) connect respectively soft barrier film three (10) and soft barrier film four (11), and pressure reduction drain valve (8) is positioned between soft barrier film three (10) and soft barrier film four (11) and is fixed on valve rod three (9);
Described follow-up type backflow preventer, soft barrier film one (4) is made up of the soft barrier film of separable bilayer, and double-deck soft barrier film can be expanded the space airtight for inside, and the inner breathing pipe (23) that passes through is communicated with atmosphere.
2. follow-up type backflow preventer according to claim 1, is characterized in that, described gravity type safety check one (2) and gravity type safety check two (5) are non-gravity type safety check.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410042043.6A CN103821969A (en) | 2014-01-28 | 2014-01-28 | Follow-up backflow preventer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410042043.6A CN103821969A (en) | 2014-01-28 | 2014-01-28 | Follow-up backflow preventer |
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| Publication Number | Publication Date |
|---|---|
| CN103821969A true CN103821969A (en) | 2014-05-28 |
Family
ID=50757176
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|---|---|---|---|
| CN201410042043.6A Pending CN103821969A (en) | 2014-01-28 | 2014-01-28 | Follow-up backflow preventer |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114593216A (en) * | 2022-04-13 | 2022-06-07 | 中恒水务科技有限公司 | Non-resistance backflow preventer of double butterfly valves |
| CN114593224A (en) * | 2022-04-13 | 2022-06-07 | 中恒水务科技有限公司 | Non-resistance backflow preventer with double gate valves |
| CN114658878A (en) * | 2022-04-13 | 2022-06-24 | 中恒水务科技有限公司 | Non-resistance backflow preventer with double ball valves |
| CN114658862A (en) * | 2022-04-13 | 2022-06-24 | 中恒水务科技有限公司 | Resistance-free backflow preventer with double stop valves |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114593216A (en) * | 2022-04-13 | 2022-06-07 | 中恒水务科技有限公司 | Non-resistance backflow preventer of double butterfly valves |
| CN114593224A (en) * | 2022-04-13 | 2022-06-07 | 中恒水务科技有限公司 | Non-resistance backflow preventer with double gate valves |
| CN114658878A (en) * | 2022-04-13 | 2022-06-24 | 中恒水务科技有限公司 | Non-resistance backflow preventer with double ball valves |
| CN114658862A (en) * | 2022-04-13 | 2022-06-24 | 中恒水务科技有限公司 | Resistance-free backflow preventer with double stop valves |
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Application publication date: 20140528 |