CA3042108C - Anti-pollution micro-resistance slow-closing check valve and industrial drainage system - Google Patents
Anti-pollution micro-resistance slow-closing check valve and industrial drainage system Download PDFInfo
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- CA3042108C CA3042108C CA3042108A CA3042108A CA3042108C CA 3042108 C CA3042108 C CA 3042108C CA 3042108 A CA3042108 A CA 3042108A CA 3042108 A CA3042108 A CA 3042108A CA 3042108 C CA3042108 C CA 3042108C
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- 238000013016 damping Methods 0.000 claims abstract description 50
- 230000007246 mechanism Effects 0.000 claims abstract description 50
- 239000012530 fluid Substances 0.000 claims abstract description 39
- 238000004891 communication Methods 0.000 claims abstract description 28
- 125000006850 spacer group Chemical group 0.000 claims abstract description 28
- 230000003139 buffering effect Effects 0.000 claims abstract description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 61
- 239000012528 membrane Substances 0.000 claims description 16
- 239000010720 hydraulic oil Substances 0.000 claims description 15
- 230000008859 change Effects 0.000 claims description 7
- 239000002609 medium Substances 0.000 description 139
- 239000007788 liquid Substances 0.000 description 21
- 239000012535 impurity Substances 0.000 description 11
- 230000000694 effects Effects 0.000 description 9
- 230000009471 action Effects 0.000 description 7
- 238000000034 method Methods 0.000 description 6
- 238000007789 sealing Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 4
- 238000002955 isolation Methods 0.000 description 3
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000001066 destructive effect Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000001802 infusion Methods 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 239000007062 medium k Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
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- 239000003921 oil Substances 0.000 description 1
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- 230000003068 static effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Classifications
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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
- F16K15/18—Check valves with actuating mechanism; Combined check valves and actuated valves
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
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- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Check Valves (AREA)
- Details Of Valves (AREA)
- Water Treatment By Sorption (AREA)
Abstract
The disclosure relates to an anti-pollution micro-resistance slow-closing check valve and an industrial drainage system. The check valve comprises: a valve body, a valve flap, a valve stem, a piston cylinder and a buffering mechanism. A first working chamber and a second working chamber in communication with each other are provided in the valve body for a working fluid medium to pass through. The buffering mechanism is capable of buffering the movement of the piston. The medium chamber in one side of the piston cylinder away from the valve stem is in communication with the second working chamber and is provided therein with a ductile spacer for isolating the damping medium within the piston cylinder and a working fluid medium from the second working chamber.
Description
ANTI-POLLUTION MICRO-RESISTANCE SLOW-CLOSING CHECK VALVE
AND INDUSTRIAL DRAINAGE SYSTEM
FIELD OF THE DISCLOSURE
100011 The disclosure relates to a check valve, especially an anti-pollution micro-resistance slow-closing check valve and an industrial drainage system.
BACKGROUND OF THE DISCLOSURE
AND INDUSTRIAL DRAINAGE SYSTEM
FIELD OF THE DISCLOSURE
100011 The disclosure relates to a check valve, especially an anti-pollution micro-resistance slow-closing check valve and an industrial drainage system.
BACKGROUND OF THE DISCLOSURE
[0002] A check valve is a valve which automatically opens and closes a valve flap by flow of a medium itself to prevent the medium from flowing backwards. Its basic function is to protect the apparatus by preventing a liquid backflow in the drainage system, which is especially important for apparatuses, such as pumps and compressors. In the prior art, a check valve usually comprises a valve body, a valve flap, a valve stem, a spring and other parts. In an industrial drainage system, when a centrifugal pump is powered off suddenly, which causes a liquid backtlow in the pipeline, the liquid flowing backwards will produce a water hammer and thus damage the drainage system. The water hammer refers to the phenomenon of hydraulic transition in which pressure rises or falls because of the change of flow velocity of fluid in a pressure pipeline. The physical principle is that it is the result of the combined action of the incompressibility of liquid, the movement inertia of fluid and the elasticity of pipes. In order to mitigate and eliminate water hammer of the check valve, a buffer device needs to be provided in the check valve, through which the valve flap is closed slowly in the course of upcoming closure, so as to achieve the effect of mitigating and eliminating water hammer.
[0003] FIG. I is a schematic view of the structure of an existing micro-resistance slow-closing check valve for a drainage system. In FIG. I, the micro-resistance slow-closing check valve comprises a main valve body al, a valve flap a2, a valve stem a3, a spring a4, a piston cylinder a5 and a slow-closing cylinder a6. The piston cylinder a5 is mounted on the main valve body al, and the valve stem a3 is connected with a piston within the piston cylinder a5. When the water pump begins to work, pressure of the fluid entering the inlet chamber of the main valve body al keeps rising, part of the water flows through a small ball valve and a filter, and enters the lower chamber of the piston cylinder through a water opening a7 at the lower chamber, water pressure acts on the piston to push the valve stem a3 to move upwards, which drives the slow-closing cylinder a6 to move upwards, the valve flap a2 is opened under the action of the pressure water at the pump outlet, then valve opening is completed. At the same time, water in the upper chamber of the piston cylinder flows through a water opening a8 at the upper chamber, and then through the small ball valve and the filter to be discharged into the outlet chamber of the main valve body al.
[0004] The slow-closing cylinder a6 is provided with a throttle valve therein.
Controlling of the throttle valve can play a role of throttling, to ensure that the opening time of the main valve is greater than the start time of the water pump motor, to achieve light-load startup of the pump and avoid direct water hammer. When the water pump stops working, pressure at the valve inlet chamber drops rapidly, and the pressure at the valve outlet chamber is higher than the pressure at the inlet chamber, the valve flap a2 falls rapidly under its own gravity. At the same time, water in the outlet chamber flows through the small ball valve and the filter and then enters the upper chamber of the piston cylinder through the water opening a8 at the upper chamber. The valve is closed under the dual action of fluid pressure of water and the spring force, and water flow is interrupted. Water in the lower chamber of the piston cylinder flows through the filter and the ball valve to the main valve inlet chamber, and the valve stem a3 descends, driving the slow-closing cylinder a6 to descend. By adjusting the opening degree of the throttle valve in the slow-closing cylinder a6, the operation speed of the piston is controlled, thus slow closing of the valve flap a2 is achieved and pump-failure water hammer is eliminated.
Controlling of the throttle valve can play a role of throttling, to ensure that the opening time of the main valve is greater than the start time of the water pump motor, to achieve light-load startup of the pump and avoid direct water hammer. When the water pump stops working, pressure at the valve inlet chamber drops rapidly, and the pressure at the valve outlet chamber is higher than the pressure at the inlet chamber, the valve flap a2 falls rapidly under its own gravity. At the same time, water in the outlet chamber flows through the small ball valve and the filter and then enters the upper chamber of the piston cylinder through the water opening a8 at the upper chamber. The valve is closed under the dual action of fluid pressure of water and the spring force, and water flow is interrupted. Water in the lower chamber of the piston cylinder flows through the filter and the ball valve to the main valve inlet chamber, and the valve stem a3 descends, driving the slow-closing cylinder a6 to descend. By adjusting the opening degree of the throttle valve in the slow-closing cylinder a6, the operation speed of the piston is controlled, thus slow closing of the valve flap a2 is achieved and pump-failure water hammer is eliminated.
[0005] However, in actual production, such check valves have the following deficiencies in harsh working conditions:
[0006] 1. When water in the drainage system is relatively turbid, or when the conveyed liquid itself contains impurities, the impurities in the liquid will enter the upper and lower chambers of the piston cylinder, and after impurities are accumulated in the piston cylinder, the valve stem cannot move up and down, which causes a valve failure.
[0007] 2. The outlet and inlet chambers of the main valve are respectively in communication with the upper and lower chambers of the piston cylinder by means of a pilot line, and when the turbid liquid being conveyed flows through a relatively thin pilot line, impurities in the liquid are liable to be accumulated therein, causing blockage and failure to close the check valve.
[0008] 3. As the medium conveyed by the drainage system is relatively turbid, impurities in the conveyed medium will enter the piston cylinder along with the medium.
The operation speed of the piston is controlled by setting the opening degree of the throttle valve in the slow-closing cylinder, thus the moving speed of the valve flap is controlled.
Although the throttle valve can eliminate water hammer, the overall speed for opening and closing the valve flap is slow.
SUMMARY OF THE DISCLOSURE
The operation speed of the piston is controlled by setting the opening degree of the throttle valve in the slow-closing cylinder, thus the moving speed of the valve flap is controlled.
Although the throttle valve can eliminate water hammer, the overall speed for opening and closing the valve flap is slow.
SUMMARY OF THE DISCLOSURE
[0009] It is an object of the present disclosure to provide an anti-pollution micro-resistance slow-closing check valve and an industrial drainage system, which can eliminate water hammer as much as possible, and the check valve is not liable to fail.
[0010] In order to achieve the above object, the present disclosure provides an anti-pollution micro-resistance slow-closing check valve, comprising: a valve body, a valve flap, a valve stem, a piston cylinder and a bufkring mechanism. A first working chamber and a second working chamber in communication with each other are provided in the valve body for a working fluid medium to pass through. The piston cylinder is mounted on one side of the valve body near the second working chamber. Both ends of the valve stem are respectively connected with the valve flap and a piston within the piston cylinder, such that the piston and the valve stem move synchronously with the valve flap to close or open a communication passage between the first and second working chambers. The buffering mechanism is capable of buffering the movement of the piston.
[0011] The medium chamber in one side of the piston cylinder away from the valve stem is in communication with the second working chamber and is provided with a ductile spacer therein, for isolating a damping medium within the piston cylinder and a working fluid medium from the second working chamber.
[0012] Further, the buffering mechanism comprises a throttle mechanism disposed within the piston cylinder, the throttle mechanism is located between the medium chambers on both sides of the piston, for slowing down relative flow between the damping media on both sides of the piston.
[0013] Further, the throttle mechanism comprises an orifice and a cone stopper provided on the piston. The medium chambers on both sides of the piston are in communication through the orifice. The cone stopper is provided in the orifice, for providing a throttling effect for the damping medium passing therethrough.
[0014] Further, the buffering mechanism comprises a medium passage provided within the piston cylinder, for providing communication between the damping media in the medium chambers on both sides of the piston. The medium passage is further provided with an on-off mechanism for controlling the connection or disconnection of the medium passage.
[0015] Further, the on-off mechanism can control the medium passage to be disconnected in the opening initial stage and/or the closing end stage of the valve flap, and control the medium passage to be connected during other movement stages of the valve flap.
[0016] Further, the on-off mechanism is a stroke-based on-off switch.
[0017] Further, the medium passage is provided on the piston, the piston cylinder is provided therein with a guide rod fixed with respect to the piston cylinder, and the guide rod is inserted in the medium passage. The cross-sectional dimension of the guide rod changes in the lengthwise direction. Under the first predetermined stroke of the piston, the cross-sectional dimension on the guide rod corresponding to the current position of the piston is less than the cross-sectional dimension of the medium passage, such that the damping media within the medium chambers on both sides of the piston can flow through the gap between the guide rod and the medium passage; under the second predetermined stroke of the piston, the cross-sectional dimension on the guide rod corresponding to the current position of the piston is equivalent to the cross-sectional dimension of the medium passage, such that the damping media within the medium chambers on both sides of the piston cannot pass through the medium passage.
[0018] Further, the spacer is a rubber membrane capable of extending and deforming towards the inside or outside of the piston cylinder with the change of the pressure relationship between the damping medium in the piston cylinder and the working fluid medium from the second working chamber.
[0019] Further, the piston cylinder comprises a cylinder body, a valve cover and the piston, the cylinder body is mounted on the valve body by means of a flange, the valve cover is mounted on one side of the cylinder body away from the valve stem, the spacer is provided on the inner side of the valve cover, and the space between the valve cover and the spacer is in communication with the second working chamber.
[0020] Further, the valve cover is provided therein with a hollow inner chamber, and the hollow inner chamber and the second working chamber are in communication by means of a pipeline.
[0021] Further, a filter is provided in one side of the pipeline near the second working chamber.
[0022] Further, a spring is provided between the valve cover and the piston, and the spring is soaked in the damping medium in the piston cylinder.
[00231 Further, the damping medium in the piston cylinder is a hydraulic oil.
[0024] Further, the valve stem and the piston cylinder are disposed vertically when the valve body is disposed in a horizontal state.
[0025] Further, an axis of the inlet and outlet of the first working chamber coincides with an axis of the inlet and outlet of the second working chamber, which is parallel to the plane on which the valve flap is located.
[0026] Further, there is a glyd ring disposed between the piston and the cylinder body and/or between the valve stem and the flange and an 0-ring disposed between the cylinder body and the flange and/or between the valve body and the flange.
[0027] Further, the spacer is a rubber membrane, the valve cover is provided with a center hole through which a spring seat is fitted, both ends of the spring are respectively connected to the spring seat and the piston, the spring seat is sleeved with a spacer bush, and the rubber membrane is clamped and fixed by the spring seat and the spacer bush.
[0028] In order to achieve the abovementioned object, the present disclosure provides an industrial drainage system comprising a water pump, characterized in that it further comprises the aforementioned anti-pollution micro-resistance slow-closing check valve which is provided on the outfall side of the water pump.
[0029] Based on the abovementioned technical solution, the present disclosure uses a buffering mechanism in the check valve to buffer the movement of the piston of the piston cylinder, such that the valve flap can slowly open and/or close the communication passage between the inlet chamber and the outlet chamber of the check valve, thereby eliminating water hammer caused at the moment of opening and/or closing; the present disclosure also provides a ductile spacer in the medium chamber in one side of the piston cylinder away from the valve stem, and uses the spacer to isolate the damping medium in the piston cylinder for controlling the movement of the valve stem and the working fluid medium k from the outlet chamber of the check valve, which avoids blockage and failure of the piston cylinder or the buffering mechanism caused by the impurities in the working fluid medium entering the piston cylinder, and also avoids pollution of the working fluid medium by the damping medium.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[0030] Drawings explained here are used to provide further understanding of the present disclosure, which constitute a portion of the present application. The schematic embodiments and description of the present disclosure are used for explaining the present disclosure, and do not constitute improper delimitations of the present disclosure. In the drawings:
[0031] FIG. 1 is a schematic view of the structure of an existing micro-resistance slow-closing check valve for a drainage system.
[0032] FIG. 2 is a schematic view of the sectional structure of an embodiment of the anti-pollution micro-resistance slow-closing check valve according to the present disclosure.
[0033] FIG. 3 is a schematic view of the structure of an embodiment of the anti-pollution micro-resistance slow-closing check valve according to the present disclosure, viewing from the right of the second working chamber to the second working chamber.
[0034] FIG. 4 is a schematic top view of the structure of an embodiment of the anti-pollution micro-resistance slow-closing check valve according to the present disclosure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0035] Next, the technical solution of the present disclosure will be further described in detail through drawings and embodiments.
[0036] Regarding the problem of check valve failure existing in the prior art, after observing and researching, the inventor notes that a check valve fails mainly because impurities in the conveyed liquid of the drainage system block the piston cylinder or the pilot line or the like, and blockage occurs because apart from acting as a liquid medium to be conveyed, the conveyed liquid also needs to play a role as a pilot liquid for opening and closing the valve flap, which enables the impurities have access to the pilot pipeline and k the piston cylinder, causing hidden danger of blockage.
[0037] For this reason, the inventor provides damping medium in the piston cylinder to play an intermediate role of transferring pressure, and uses a ductile spacer to allow the damping medium and the working fluid medium to be separated from each other while transferring pressure between each other, so as to prevent the impurities from directly entering the piston cylinder and easily blocking the operation position of the piston, such that the check valve is not liable to fail.
[0038] FIG. 2 is a schematic view of the sectional structure of an embodiment of the anti-pollution micro-resistance slow-closing check valve according to the present disclosure, based on the abovementioned principle. In combination with the schematic views of FIGS. 3 and 4 from different perspectives, the anti-pollution micro-resistance slow-closing check valve in the present embodiment comprises: a valve body 1, a valve flap 2, a valve stem 3, a piston cylinder and a buffering mechanism. The valve body 1 is provided therein with a first working chamber A and a second working chamber B
in communication with each other for working fluid medium passing through. The first working chamber A and the second working chamber B herein respectively serve as an inlet chamber and an outlet chamber of the working fluid medium when the valve flap 2 is opened, and the working fluid medium flows backwards into the second working chamber B when a liquid backflow occurs.
[0039] A communication passage is formed between the first working chamber A
and the second working chamber B, and the valve flap 2 is movable with respect to the communication passage. The communication passage is opened or closed at different movement positions of the valve flap 2.
[0040] The piston cylinder is mounted on one side of the valve body 1 near the second working chamber B, and both ends of the valve stem 3 are respectively connected with the valve flap 2 and a piston 20 in the piston cylinder. The piston 20 and the valve stem 3 move synchronously with the valve flap 2 to close or open the communication passage between the first working chamber A and second working chamber B. The valve flap 2 can be axially fixed with the valve stem 3 by a nut 23 below. The upper end of the valve stem 3 can be axially fixed with the piston 20 by a nut 12.
[0041] The function of the buffering mechanism is to buffer the movement of the piston 20, such that the valve flap 2 is decelerated at the moment of opening and/or closing to prevent the flow velocity of the working fluid medium rapidly increasing from zero to a larger flow rate or rapidly decreasing from a larger flow rate to zero, which causes a water hammer that damages the system. It should be noted that, the water hammer herein does not specifically refer to the application in which the working fluid medium is water, it also applies to other working fluid media in a liquid state, such as oil, mixed liquid or the like.
[0042] A damping medium is provided in the piston cylinder, the piston cylinder is provided with a first medium chamber and a second medium chamber respectively provided on both sides of the piston 20 and communicating with each other, and the first medium chamber is away from the valve stem 3, the second medium chamber is near the valve stem 3. The first medium chamber is in communication with the second working chamber B, and a ductile spacer is provided in the first medium chamber for isolating the damping medium within the piston cylinder and the working fluid medium from the second working chamber B. This enables the pressure of the working fluid medium in the second working chamber B to be transferred to the medium chamber of the piston cylinder, and the pressure effect acting on the damping medium in the medium chamber by the working fluid medium is then transferred to the piston to drive the piston to move and thus drive the valve flap to move. The damping medium may be hydraulic oil or other liquid fluid that can flow and transfer pressure effect.
[0043] When a liquid backflow occurs in the system, the working fluid medium will flow backwards into the second working chamber B. The pressure of the working fluid medium is transferred to the piston through the damping medium, which can drive the valve flap to be closed, so as to prevent the liquid from flowing backwards into the first working chamber A of the check valve. The spacer used here can isolate the damping medium in the piston cylinder for controlling the movement of the valve stem and the working fluid medium from the outlet chamber of the check valve, which avoids blockage and failure of the piston cylinder or the buffering mechanism caused by the impurities in the working fluid medium entering the piston cylinder, and also avoids pollution of the working fluid medium by the damping medium.
[0044] The spacer may be a rubber membrane 17. A spacer made of such material is capable of extending or deforming towards the inside or outside of the piston cylinder with the change of the pressure relationship between the damping medium in the piston cylinder and the working fluid medium from the second working chamber B. Moreover, the rubber membrane 17 has a good isolation effect.
[0045] It is mentioned earlier that the buffering mechanism is capable of buffering the movement of the piston 20. such that the valve flap 2 is decelerated at the moment of opening and/or closing. It may be provided within the piston cylinder or outside the piston cylinder. For example, the slow-closing cylinder a6 in the prior art similar to the one shown in FIG. I may also be applied to the anti-pollution micro-resistance slow-closing check valve of the present disclosure.
[0046] The buffering mechanism shown in FIG. 2 comprises a throttle mechanism provided within the piston cylinder. The throttle mechanism is located between the medium chambers on both sides of the piston 20, and communicates the first medium chamber and the second medium chamber, for throttling the damping medium passing therethrough. The throttle mechanism can slow down relative flow between the damping media on both sides of the piston 20. By decreasing the flow velocity of the damping medium, the moving speed of the piston can be suppressed, such that the valve flap can be slowly opened or closed at the moment of opening and/or closing, thereby reducing or eliminating water hammer. The throttle mechanism is provided within the piston cylinder, which can realize the functions of throttling, decelerating and driving the valve flap at the same time, and the structure is more compact with less space occupied. It should be noted that, in different embodiments of the present disclosure, the slow opening and slow closing of the valve flap may be independent of each other, so that slow opening or slow closing may be performed alone to eliminate water hammer in the opening or closing process; in addition, the slow opening and slow closing of the valve flap may also be interrelated, that is, slow opening and slow closing may be realized at the same time to eliminate water hammer in the opening or closing process.
[0047] The throttle mechanism may be implemented in a variety of ways, for example, the throttle mechanism shown in FIG. 2 comprises an orifice and a cone stopper provided on the piston 20. The orifice may be machined in the form of a tapered threaded hole, such that the cone stopper 11 is screwed into the threaded hole. The first medium chamber and the second medium chamber are in communication through the orifice. The cone stopper 11 is provided in the orifice, for throttling the damping medium passing therethrough. When the piston 20 is pushed, the damping medium in the medium chambers on both sides of the piston 20 within the piston cylinder flows through the orifice, and the throttling effect of the cone stopper 11 reduces the flow velocity between the medium chambers on both sides of the piston 20, thereby suppressing the moving speed of the piston 20. The orifice is provided on the piston 20, which is not only more convenient to machine but also capable of keeping the communication state between the medium chambers on both sides of the piston 20 without being limited by the position of the piston 20. In other embodiments, the orifice and cone stopper may also be provided on other structures, such as on the valve stem or on the cylinder body of the piston cylinder.
Moreover, the throttle mechanism is not limited to the combination of an orifice and a cone stopper, it may also be an independent orifice, etc.
[0048] In order to control the operation process of the valve flap and the piston better, a medium passage disposed within the piston cylinder may also be added to the buffering mechanism, for communicating the first medium chamber and the second medium chamber.
The medium passage is further provided with an on-off mechanism for connecting or disconnecting the medium passage. Through the on-off mechanism, the damping medium within the first medium chamber and the second medium chamber can bypass or fail to bypass the throttling and decelerating action of the throttle mechanism. The on-off mechanism can realize the slow and fast stage control for the piston.
[0049] Considering that the check valve requires slow speed at the moment of opening and closing, while it requires the opening and closing operations to be finished as soon as possible in other movement stages, in order to improve system efficiency and reduce the risk of backflow of the working fluid medium. Thus, preferably the on-off mechanism controls the medium passage to be disconnected in the opening initial stage and/or the closing end phase of the valve flap. At this time, the damping medium within the first medium chamber and the second medium chamber can only flow through the throttle mechanism, such that slow movement of the valve flap at the moment of opening or closing is achieved by the throttling and decelerating action of the throttle mechanism.
[0050] Preferably, the on-off mechanism controls the medium passage to be connected in other movement stages of the valve flap (i.e., other movement stages except the opening initial stage and/or the closing end stage in all the movement stages of the valve flap).
Since the flow area of the medium passage is greater than (or much greater than) the flow area of the throttle mechanism, for example, greater than one time or more than one time, the damping medium within the first medium chamber and the second medium chamber will preferably pass through the medium passage with a larger flow area, which is equivalent to temporarily cancelling the throttling and decelerating action of the throttle mechanism against the damping medium. Of course, a small part of the damping medium will flow through the throttle mechanism. As a result, the flow velocity of the damping medium Is increased, so that the piston, the valve stem and the valve flap are all able to move rapidly, such that the check valve of the present disclosure can lift the valve flap rapidly during the opening process, except the slow opening in the opening initial stage corresponding to the opening moment, to ensure to quickly realize through flow of the check wave.
[0051] In the event of a liquid backflow, under the pressure of the working fluid medium in the second working chamber, the valve flap is able to be quickly switched from a fully open state to a closed state and decelerate to close at the moment of closing, which can not only reduce the destructive effect of the working fluid medium flowing backwards on the elements and pipelines in the system, but also eliminate water hammer upon closing.
[0052] In order to realize the on-off control of the medium passage in different movement stages of the valve flap, the on-off mechanism may be a stroke-based on-off switch, that is, on-off operation of the medium passage is triggered by the movement stroke of the valve flap, the valve stem or the piston. Such on-off operation may be a purely mechanical operation or a mechanical control based on electrical signals. For example, in other embodiments, the on-off mechanism may also employ an electrically controlled switch based on a pressure signal of the working fluid medium, a position sensor signal of the valve flap, etc.
[0053] A specific embodiment of the on-off mechanism is shown in FIG. 2. In FIG. 2, the medium passage is provided on the piston 20, the piston cylinder is provided therein with a guide rod 19 fixed with respect to the piston cylinder, and the guide rod 19 is inserted in the medium passage. The cross-sectional dimension of the guide rod 19 changes in the lengthwise direction. The guide rod 19 may be fixed on a flange 6 between the valve body 1 and the piston cylinder, or it may be chosen to be fixed on the cylinder body 21 or on the valve cover 13 of the piston cylinder in accordance with the internal structure of the piston cylinder. The change of the cross-sectional dimension of the guide rod 19 in the lengthwise direction may be machined by milling to produce a lateral flat groove or a circular internal recessed groove.
100541 During the first predetermined stroke of the piston 20, such as other movement stages except the opening initial stage and the closing end stage of the valve flap 2, the cross-sectional dimension on the guide rod 19 corresponding to the current position of the piston 20 is less than the cross-sectional dimension of the medium passage, such that the damping media within the medium chambers on both sides of the piston 20 can flow through the gap between the guide rod 19 and the medium passage.
[0055] During the second predetermined stroke of the piston 20, such as the opening initial stage and the closing end stage of the valve flap 2, the cross-sectional dimension on the guide rod 19 corresponding to the current position of the piston 20 is equivalent to the cross-sectional dimension of the medium passage, such that the damping media within the medium chambers on both sides of the piston 20 fail to pass through the medium passage.
At this time, the damping medium can only flow between the medium chambers on both sides of the piston 20 through the throttle mechanism (for example, the orifice and the cone stopper 11 in FIG. 2), thereby achieving the throttling and decelerating effect on the movement of the piston 20.
[0056] The configuration of an example of the piston cylinder will be explained below with reference to FIG. 2. The piston cylinder comprises a cylinder body 21, a valve cover 13 and the piston 20. The cylinder body 21 is mounted on the valve body 1 by means of a flange 6. The valve cover 13 is mounted on one side of the cylinder body 21 away from the valve stem 3. The spacer is provided on the inner side of the valve cover 13.
A space between the valve cover 13 and the spacer is in communication with the second working chamber B.
[0057] Wherein, preferably the valve cover 13 is provided therein with a hollow inner chamber, and the hollow inner chamber and the second working chamber B are in communication through a pipeline 8. Since the pipeline 8 needs to receive the working fluid medium from the second working chamber B, the pipeline 8 may be a pipeline member with a relatively large diameter in order to prevent blockage of the pipeline 8, and a filter may be provided in one side of the pipeline 8 near the second working chamber B, for filtering the impurities in the working fluid medium. The pipeline 8 may be connected to the valve cover 13 and the valve body 1 respectively through a pipeline joint 10 and a pipeline joint 7. Both ends of the pipeline 8 may be respectively welded to the pipeline joint 10 and the pipeline joint 7. The pipeline joint 10 may be threadedly connected to the valve cover 13 and the pipeline joint 7 may be threadedly connected to the second working chamber of the valve body I.
[0058] Under the isolation effect of the spacer (e.g., the rubber membrane 17), the working fluid medium with a certain pressure from the second working chamber B
can extend the spacer towards the inside of the piston cylinder, but it cannot really enter the damping medium, the piston, the valve stem and other parts inside the piston cylinder, so that even if it is very turbid, it cannot adversely affect the normal operation of the piston cylinder.
[0059] A spring 18 is further provided between the valve cover 13 and the piston 20, and the spring 18 is located in the damping medium within the piston cylinder. The elastic force of the spring 18 is capable of cooperating with the self weight of the valve stem 3 and the valve flap 2 and the pressure of the damping medium to enable the valve flap 2 to be closed as soon as possible. In certain cases, when the check valve is non-horizontally placed and the self weight of the valve stem 3 and the valve flap 2 plays a small role, the elastic force of the spring 18 can still help the valve flap 2 to be closed.
The material of the spring 18 is usually a metal or an alloy which is liable to corrosion during long-time use, and the damping medium is usually hydraulic oil or other media which can make the spring 18 less liable to corrosion and increase the service life of the spring 18.
The spring 18 is provided in the piston cylinder, mounting and dismounting of the spring can be simplified.
The spring can be mounted and dismounted just by opening the valve cover, thus making the spring easier to be replaced. The spring shown in FIG. 1 is provided between the valve flap and the flange, so the flange and the valve flap need to be removed to mount the spring, which makes the spring not easy to be replaced.
[0060] For the arrangement manner of the piston cylinder, preferably the valve stem 3 and the piston cylinder are designed to be vertically disposed when the valve body 1 is placed horizontally. The direction in which the piston cylinder is disposed can facilitate the infusion of damping medium, and there is no such a problem that the inclined piston cylinder shown in FIG. 1 is difficult to be filled up due to the inclination of the liquid surface. In addition, preferably an axis of the inlet and outlet of the first working chamber A coincides with an axis of the inlet and outlet of the second working chamber B, which is parallel to the plane on which the valve flap 2 is located. In combination with the lateral view of FIG. 3, it can be understood that not only the valve body itself is easy to manufacture, but also the sealing surface inside the valve is relatively easy to machine.
[0061] In order to ensure the sealing property between various combined components, a glyd ring and an 0-ring may be provided in the anti-pollution micro-resistance slow-closing check valve. A glyd ring is a sealing ring formed by combining a rubber 0-ring and a teflon ring, the friction is small with no creeping phenomenon and good static sealing performance, and it can be used safely in a medium containing dirt. In the check valve of the present disclosure, the glyd ring is mainly used for the sealing between movement contacts, for example, a glyd ring 9 is provided between the piston 20 and the cylinder body 21, and/or a glyd ring 4 is provided between the valve stem 3 and the flange 6. An 0-ring is a rubber sealing ring with a circular cross section, which mainly seals a liquid in a stationary state, for example, an 0-ring 22 is provided between the cylinder body 21 and the flange 6 and/or an 0-ring 5 is between the valve body 1 and the flange 6.
[0062] The isolation effect of the rubber membrane 17 has been mentioned earlier, and FIG. 2 shows a reference of the fixing method thereof. That is, the valve cover 13 is provided with a center hole through which a spring seat 15 is fitted, both ends of the spring 18 are respectively connected to the spring seat 15 and the piston 20, the spring seat 15 is sleeved with a spacer bush 16, and the rubber membrane 17 is clamped and fixed by the spring seat 15 and the spacer bush 16.
[0063] Based on the description of the aforementioned embodiments of the anti-pollution micro-resistance slow-closing check valve, the present disclosure also provides an industrial drainage system comprising a water pump and the aforementioned anti-pollution micro-resistance slow-closing check valve, wherein the anti-pollution micro-resistance slow-closing check valve is provided on the outlet side of the water pump, for preventing the impact of water backflow against the water pump, thereby forming a protective effect for the water pump.
[0064] Next, in combination with the structures of the specific embodiments of the anti-pollution micro-resistance slow-closing check valve shown in FIGS. 2-4, the main procedure of the application in the industrial drainage system is explained.
Firstly, it is needed to connect the anti-pollution micro-resistance slow-closing check valve into the industrial drainage system, connect the first working chamber A of the valve body 1 to the outlet side of the water pump, and connect the second working chamber B to the water using side. At the same time, damping medium (for example, hydraulic oil) needs to be infused into the piston cylinder of the anti-pollution type micro-resistance slow-closing check valve in advance, and one end of the pipeline is need to be connected with the valve cover 13 through the pipe joint 10, and the other end of the pipeline is connected with the second working chamber B through the pipe joint 7. In the original state, the piston 20, the valve stem 3 and the valve flap 2 are at the bottom position for closing the passage between the first working chamber A and the second working chamber B, under the action of the self weight thereof and the elastic force of the spring 18.
[0065] When the water pump is started, the water pumped by the pump enters the first working chamber A, and when a certain pressure is accumulated in the first working chamber A, the self weight of the piston 20, the valve stem 3 and the valve flap 2 and the elastic force of the spring 18 can be overcome thus lifting up the valve flap 2. At this opening initial stage, the cross-sectional dimension of the position on the guide rod 19 coinciding with the medium passage on the piston 18 is the same as the cross-sectional dimension of the medium passage, so that the hydraulic oil fails to pass through the medium passage. and it can only pass through the orifice and the cone stopper 11 on the other side, such that the hydraulic oil in the upper chamber of the piston 18 flows to the lower chamber at a relatively slow speed, so that opening of the valve flap 2 is carried out at a slow speed. This allows the flow velocity of the water pumped by the water pump not to change too fast and form water hammer against the drainage system.
[0066] After passing the opening initial stage, the piston 18 moves upwards and correspondingly the cross-sectional dimension of the position on the guide rod coinciding with the medium passage on the piston 18 is changed, i.e., both sides of the cylinder of the guide rod 17 are milled, making it smaller than the cross-sectional dimension of the medium passage. At this time, since the gap between the guide rod 19 and the medium passage is much larger than that the orifice and the cone stopper 11, the hydraulic oil in the upper chamber preferably flows from the gap to the lower chamber, so that the flow velocity of the hydraulic oil is increased, such that the piston 18 can quickly rise, thus making the valve flap quickly leave the closed position. When the acting force of water, the self weight of the piston 20, the valve stem 3 and the valve flap 2, and the elastic force of the spring 18 are balanced, the valve flap 2 stops rising and reaches the maximum opening degree. During rise of the valve flap, since the valve stem 3 occupies a certain volume in the inner chamber of the piston cylinder, it will cause an upward protrusion of the rubber membrane 17. When the valve flap 2 reaches the maximum opening degree, the water pumped by the water pump can substantially unimpededly pass through the check valve.
[0067] When emergencies such as blockage and sudden stop of the water pump happen to the industrial drainage system, and the water pressure on the water using side is higher than that on the pump side, backflow of water occurs. That is, water flows into the second working chamber B and then flows out of the first working chamber A. Since the pressure of the second working chamber B is greater than the pressure of the first working chamber A, a part of the backward water flows through the valve body 1 and another part enters the hollow chamber of the valve cover 13 through the pipeline 8 and acts on the rubber membrane 17 between the cylinder body 21 and the valve cover 13. The water acting on the rubber membrane 17 can transfer the motion state to the hydraulic oil in the piston chamber through the rubber membrane 17, the movement of the hydraulic oil then acts on the piston 20, and the valve flap 2 moves downwards under the combined action of water pressure of the valve flap 2, pressure of the hydraulic oil against the piston 20, the elastic force of the spring 18 and the self weight of the piston 20, the valve stem 3 and the valve flap 2.
[0068] In the initial stage of descending, the overlapping position of the guide rod 19 and the medium passage on the piston 18 is milled, such that it is smaller than the cross-sectional dimension of the medium passage, so that flow is preferably through the gap between the guide rod 19 and the medium passage. Due to the large flow area, the hydraulic oil flows relatively fast, such that the valve flap 2 rapidly descends. When the piston 20 is lowered to a certain height (corresponding to the closing end stage of the valve flap), since the rod structure of the overlapping position of the guide rod 19 and the medium passage on the piston 18 has completely filled up the medium passage, in the closing end stage of the valve core, the hydraulic oil can only flow through the orifice and the cone stopper 11, such that the hydraulic oil in the lower chamber of the piston 18 flows to the upper chamber at a relatively low speed, so that closing of the valve flap 2 is carried out at a slow speed. This allows the flow velocity of the water pumped by the water pump not to change too fast and form water hammer against the drainage system. When the valve flap 2 reaches the lowest position, the check valve is closed and the rubber membrane 17 returns to the initial state.
[0069] Finally, it should be explained that: the abovementioned embodiments are only used for explaining the technical solutions of the present disclosure instead of limiting the same; while the present disclosure has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that:
modifications can still be made to the embodiments of the present disclosure, or equivalent replacement can be made to part of the technical features thereof; and these modifications or replacement, not departing from the spirit of the technical solutions of the present disclosure, should all be contained in the scope of the technical solutions defined in the present disclosure.
[00231 Further, the damping medium in the piston cylinder is a hydraulic oil.
[0024] Further, the valve stem and the piston cylinder are disposed vertically when the valve body is disposed in a horizontal state.
[0025] Further, an axis of the inlet and outlet of the first working chamber coincides with an axis of the inlet and outlet of the second working chamber, which is parallel to the plane on which the valve flap is located.
[0026] Further, there is a glyd ring disposed between the piston and the cylinder body and/or between the valve stem and the flange and an 0-ring disposed between the cylinder body and the flange and/or between the valve body and the flange.
[0027] Further, the spacer is a rubber membrane, the valve cover is provided with a center hole through which a spring seat is fitted, both ends of the spring are respectively connected to the spring seat and the piston, the spring seat is sleeved with a spacer bush, and the rubber membrane is clamped and fixed by the spring seat and the spacer bush.
[0028] In order to achieve the abovementioned object, the present disclosure provides an industrial drainage system comprising a water pump, characterized in that it further comprises the aforementioned anti-pollution micro-resistance slow-closing check valve which is provided on the outfall side of the water pump.
[0029] Based on the abovementioned technical solution, the present disclosure uses a buffering mechanism in the check valve to buffer the movement of the piston of the piston cylinder, such that the valve flap can slowly open and/or close the communication passage between the inlet chamber and the outlet chamber of the check valve, thereby eliminating water hammer caused at the moment of opening and/or closing; the present disclosure also provides a ductile spacer in the medium chamber in one side of the piston cylinder away from the valve stem, and uses the spacer to isolate the damping medium in the piston cylinder for controlling the movement of the valve stem and the working fluid medium k from the outlet chamber of the check valve, which avoids blockage and failure of the piston cylinder or the buffering mechanism caused by the impurities in the working fluid medium entering the piston cylinder, and also avoids pollution of the working fluid medium by the damping medium.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[0030] Drawings explained here are used to provide further understanding of the present disclosure, which constitute a portion of the present application. The schematic embodiments and description of the present disclosure are used for explaining the present disclosure, and do not constitute improper delimitations of the present disclosure. In the drawings:
[0031] FIG. 1 is a schematic view of the structure of an existing micro-resistance slow-closing check valve for a drainage system.
[0032] FIG. 2 is a schematic view of the sectional structure of an embodiment of the anti-pollution micro-resistance slow-closing check valve according to the present disclosure.
[0033] FIG. 3 is a schematic view of the structure of an embodiment of the anti-pollution micro-resistance slow-closing check valve according to the present disclosure, viewing from the right of the second working chamber to the second working chamber.
[0034] FIG. 4 is a schematic top view of the structure of an embodiment of the anti-pollution micro-resistance slow-closing check valve according to the present disclosure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0035] Next, the technical solution of the present disclosure will be further described in detail through drawings and embodiments.
[0036] Regarding the problem of check valve failure existing in the prior art, after observing and researching, the inventor notes that a check valve fails mainly because impurities in the conveyed liquid of the drainage system block the piston cylinder or the pilot line or the like, and blockage occurs because apart from acting as a liquid medium to be conveyed, the conveyed liquid also needs to play a role as a pilot liquid for opening and closing the valve flap, which enables the impurities have access to the pilot pipeline and k the piston cylinder, causing hidden danger of blockage.
[0037] For this reason, the inventor provides damping medium in the piston cylinder to play an intermediate role of transferring pressure, and uses a ductile spacer to allow the damping medium and the working fluid medium to be separated from each other while transferring pressure between each other, so as to prevent the impurities from directly entering the piston cylinder and easily blocking the operation position of the piston, such that the check valve is not liable to fail.
[0038] FIG. 2 is a schematic view of the sectional structure of an embodiment of the anti-pollution micro-resistance slow-closing check valve according to the present disclosure, based on the abovementioned principle. In combination with the schematic views of FIGS. 3 and 4 from different perspectives, the anti-pollution micro-resistance slow-closing check valve in the present embodiment comprises: a valve body 1, a valve flap 2, a valve stem 3, a piston cylinder and a buffering mechanism. The valve body 1 is provided therein with a first working chamber A and a second working chamber B
in communication with each other for working fluid medium passing through. The first working chamber A and the second working chamber B herein respectively serve as an inlet chamber and an outlet chamber of the working fluid medium when the valve flap 2 is opened, and the working fluid medium flows backwards into the second working chamber B when a liquid backflow occurs.
[0039] A communication passage is formed between the first working chamber A
and the second working chamber B, and the valve flap 2 is movable with respect to the communication passage. The communication passage is opened or closed at different movement positions of the valve flap 2.
[0040] The piston cylinder is mounted on one side of the valve body 1 near the second working chamber B, and both ends of the valve stem 3 are respectively connected with the valve flap 2 and a piston 20 in the piston cylinder. The piston 20 and the valve stem 3 move synchronously with the valve flap 2 to close or open the communication passage between the first working chamber A and second working chamber B. The valve flap 2 can be axially fixed with the valve stem 3 by a nut 23 below. The upper end of the valve stem 3 can be axially fixed with the piston 20 by a nut 12.
[0041] The function of the buffering mechanism is to buffer the movement of the piston 20, such that the valve flap 2 is decelerated at the moment of opening and/or closing to prevent the flow velocity of the working fluid medium rapidly increasing from zero to a larger flow rate or rapidly decreasing from a larger flow rate to zero, which causes a water hammer that damages the system. It should be noted that, the water hammer herein does not specifically refer to the application in which the working fluid medium is water, it also applies to other working fluid media in a liquid state, such as oil, mixed liquid or the like.
[0042] A damping medium is provided in the piston cylinder, the piston cylinder is provided with a first medium chamber and a second medium chamber respectively provided on both sides of the piston 20 and communicating with each other, and the first medium chamber is away from the valve stem 3, the second medium chamber is near the valve stem 3. The first medium chamber is in communication with the second working chamber B, and a ductile spacer is provided in the first medium chamber for isolating the damping medium within the piston cylinder and the working fluid medium from the second working chamber B. This enables the pressure of the working fluid medium in the second working chamber B to be transferred to the medium chamber of the piston cylinder, and the pressure effect acting on the damping medium in the medium chamber by the working fluid medium is then transferred to the piston to drive the piston to move and thus drive the valve flap to move. The damping medium may be hydraulic oil or other liquid fluid that can flow and transfer pressure effect.
[0043] When a liquid backflow occurs in the system, the working fluid medium will flow backwards into the second working chamber B. The pressure of the working fluid medium is transferred to the piston through the damping medium, which can drive the valve flap to be closed, so as to prevent the liquid from flowing backwards into the first working chamber A of the check valve. The spacer used here can isolate the damping medium in the piston cylinder for controlling the movement of the valve stem and the working fluid medium from the outlet chamber of the check valve, which avoids blockage and failure of the piston cylinder or the buffering mechanism caused by the impurities in the working fluid medium entering the piston cylinder, and also avoids pollution of the working fluid medium by the damping medium.
[0044] The spacer may be a rubber membrane 17. A spacer made of such material is capable of extending or deforming towards the inside or outside of the piston cylinder with the change of the pressure relationship between the damping medium in the piston cylinder and the working fluid medium from the second working chamber B. Moreover, the rubber membrane 17 has a good isolation effect.
[0045] It is mentioned earlier that the buffering mechanism is capable of buffering the movement of the piston 20. such that the valve flap 2 is decelerated at the moment of opening and/or closing. It may be provided within the piston cylinder or outside the piston cylinder. For example, the slow-closing cylinder a6 in the prior art similar to the one shown in FIG. I may also be applied to the anti-pollution micro-resistance slow-closing check valve of the present disclosure.
[0046] The buffering mechanism shown in FIG. 2 comprises a throttle mechanism provided within the piston cylinder. The throttle mechanism is located between the medium chambers on both sides of the piston 20, and communicates the first medium chamber and the second medium chamber, for throttling the damping medium passing therethrough. The throttle mechanism can slow down relative flow between the damping media on both sides of the piston 20. By decreasing the flow velocity of the damping medium, the moving speed of the piston can be suppressed, such that the valve flap can be slowly opened or closed at the moment of opening and/or closing, thereby reducing or eliminating water hammer. The throttle mechanism is provided within the piston cylinder, which can realize the functions of throttling, decelerating and driving the valve flap at the same time, and the structure is more compact with less space occupied. It should be noted that, in different embodiments of the present disclosure, the slow opening and slow closing of the valve flap may be independent of each other, so that slow opening or slow closing may be performed alone to eliminate water hammer in the opening or closing process; in addition, the slow opening and slow closing of the valve flap may also be interrelated, that is, slow opening and slow closing may be realized at the same time to eliminate water hammer in the opening or closing process.
[0047] The throttle mechanism may be implemented in a variety of ways, for example, the throttle mechanism shown in FIG. 2 comprises an orifice and a cone stopper provided on the piston 20. The orifice may be machined in the form of a tapered threaded hole, such that the cone stopper 11 is screwed into the threaded hole. The first medium chamber and the second medium chamber are in communication through the orifice. The cone stopper 11 is provided in the orifice, for throttling the damping medium passing therethrough. When the piston 20 is pushed, the damping medium in the medium chambers on both sides of the piston 20 within the piston cylinder flows through the orifice, and the throttling effect of the cone stopper 11 reduces the flow velocity between the medium chambers on both sides of the piston 20, thereby suppressing the moving speed of the piston 20. The orifice is provided on the piston 20, which is not only more convenient to machine but also capable of keeping the communication state between the medium chambers on both sides of the piston 20 without being limited by the position of the piston 20. In other embodiments, the orifice and cone stopper may also be provided on other structures, such as on the valve stem or on the cylinder body of the piston cylinder.
Moreover, the throttle mechanism is not limited to the combination of an orifice and a cone stopper, it may also be an independent orifice, etc.
[0048] In order to control the operation process of the valve flap and the piston better, a medium passage disposed within the piston cylinder may also be added to the buffering mechanism, for communicating the first medium chamber and the second medium chamber.
The medium passage is further provided with an on-off mechanism for connecting or disconnecting the medium passage. Through the on-off mechanism, the damping medium within the first medium chamber and the second medium chamber can bypass or fail to bypass the throttling and decelerating action of the throttle mechanism. The on-off mechanism can realize the slow and fast stage control for the piston.
[0049] Considering that the check valve requires slow speed at the moment of opening and closing, while it requires the opening and closing operations to be finished as soon as possible in other movement stages, in order to improve system efficiency and reduce the risk of backflow of the working fluid medium. Thus, preferably the on-off mechanism controls the medium passage to be disconnected in the opening initial stage and/or the closing end phase of the valve flap. At this time, the damping medium within the first medium chamber and the second medium chamber can only flow through the throttle mechanism, such that slow movement of the valve flap at the moment of opening or closing is achieved by the throttling and decelerating action of the throttle mechanism.
[0050] Preferably, the on-off mechanism controls the medium passage to be connected in other movement stages of the valve flap (i.e., other movement stages except the opening initial stage and/or the closing end stage in all the movement stages of the valve flap).
Since the flow area of the medium passage is greater than (or much greater than) the flow area of the throttle mechanism, for example, greater than one time or more than one time, the damping medium within the first medium chamber and the second medium chamber will preferably pass through the medium passage with a larger flow area, which is equivalent to temporarily cancelling the throttling and decelerating action of the throttle mechanism against the damping medium. Of course, a small part of the damping medium will flow through the throttle mechanism. As a result, the flow velocity of the damping medium Is increased, so that the piston, the valve stem and the valve flap are all able to move rapidly, such that the check valve of the present disclosure can lift the valve flap rapidly during the opening process, except the slow opening in the opening initial stage corresponding to the opening moment, to ensure to quickly realize through flow of the check wave.
[0051] In the event of a liquid backflow, under the pressure of the working fluid medium in the second working chamber, the valve flap is able to be quickly switched from a fully open state to a closed state and decelerate to close at the moment of closing, which can not only reduce the destructive effect of the working fluid medium flowing backwards on the elements and pipelines in the system, but also eliminate water hammer upon closing.
[0052] In order to realize the on-off control of the medium passage in different movement stages of the valve flap, the on-off mechanism may be a stroke-based on-off switch, that is, on-off operation of the medium passage is triggered by the movement stroke of the valve flap, the valve stem or the piston. Such on-off operation may be a purely mechanical operation or a mechanical control based on electrical signals. For example, in other embodiments, the on-off mechanism may also employ an electrically controlled switch based on a pressure signal of the working fluid medium, a position sensor signal of the valve flap, etc.
[0053] A specific embodiment of the on-off mechanism is shown in FIG. 2. In FIG. 2, the medium passage is provided on the piston 20, the piston cylinder is provided therein with a guide rod 19 fixed with respect to the piston cylinder, and the guide rod 19 is inserted in the medium passage. The cross-sectional dimension of the guide rod 19 changes in the lengthwise direction. The guide rod 19 may be fixed on a flange 6 between the valve body 1 and the piston cylinder, or it may be chosen to be fixed on the cylinder body 21 or on the valve cover 13 of the piston cylinder in accordance with the internal structure of the piston cylinder. The change of the cross-sectional dimension of the guide rod 19 in the lengthwise direction may be machined by milling to produce a lateral flat groove or a circular internal recessed groove.
100541 During the first predetermined stroke of the piston 20, such as other movement stages except the opening initial stage and the closing end stage of the valve flap 2, the cross-sectional dimension on the guide rod 19 corresponding to the current position of the piston 20 is less than the cross-sectional dimension of the medium passage, such that the damping media within the medium chambers on both sides of the piston 20 can flow through the gap between the guide rod 19 and the medium passage.
[0055] During the second predetermined stroke of the piston 20, such as the opening initial stage and the closing end stage of the valve flap 2, the cross-sectional dimension on the guide rod 19 corresponding to the current position of the piston 20 is equivalent to the cross-sectional dimension of the medium passage, such that the damping media within the medium chambers on both sides of the piston 20 fail to pass through the medium passage.
At this time, the damping medium can only flow between the medium chambers on both sides of the piston 20 through the throttle mechanism (for example, the orifice and the cone stopper 11 in FIG. 2), thereby achieving the throttling and decelerating effect on the movement of the piston 20.
[0056] The configuration of an example of the piston cylinder will be explained below with reference to FIG. 2. The piston cylinder comprises a cylinder body 21, a valve cover 13 and the piston 20. The cylinder body 21 is mounted on the valve body 1 by means of a flange 6. The valve cover 13 is mounted on one side of the cylinder body 21 away from the valve stem 3. The spacer is provided on the inner side of the valve cover 13.
A space between the valve cover 13 and the spacer is in communication with the second working chamber B.
[0057] Wherein, preferably the valve cover 13 is provided therein with a hollow inner chamber, and the hollow inner chamber and the second working chamber B are in communication through a pipeline 8. Since the pipeline 8 needs to receive the working fluid medium from the second working chamber B, the pipeline 8 may be a pipeline member with a relatively large diameter in order to prevent blockage of the pipeline 8, and a filter may be provided in one side of the pipeline 8 near the second working chamber B, for filtering the impurities in the working fluid medium. The pipeline 8 may be connected to the valve cover 13 and the valve body 1 respectively through a pipeline joint 10 and a pipeline joint 7. Both ends of the pipeline 8 may be respectively welded to the pipeline joint 10 and the pipeline joint 7. The pipeline joint 10 may be threadedly connected to the valve cover 13 and the pipeline joint 7 may be threadedly connected to the second working chamber of the valve body I.
[0058] Under the isolation effect of the spacer (e.g., the rubber membrane 17), the working fluid medium with a certain pressure from the second working chamber B
can extend the spacer towards the inside of the piston cylinder, but it cannot really enter the damping medium, the piston, the valve stem and other parts inside the piston cylinder, so that even if it is very turbid, it cannot adversely affect the normal operation of the piston cylinder.
[0059] A spring 18 is further provided between the valve cover 13 and the piston 20, and the spring 18 is located in the damping medium within the piston cylinder. The elastic force of the spring 18 is capable of cooperating with the self weight of the valve stem 3 and the valve flap 2 and the pressure of the damping medium to enable the valve flap 2 to be closed as soon as possible. In certain cases, when the check valve is non-horizontally placed and the self weight of the valve stem 3 and the valve flap 2 plays a small role, the elastic force of the spring 18 can still help the valve flap 2 to be closed.
The material of the spring 18 is usually a metal or an alloy which is liable to corrosion during long-time use, and the damping medium is usually hydraulic oil or other media which can make the spring 18 less liable to corrosion and increase the service life of the spring 18.
The spring 18 is provided in the piston cylinder, mounting and dismounting of the spring can be simplified.
The spring can be mounted and dismounted just by opening the valve cover, thus making the spring easier to be replaced. The spring shown in FIG. 1 is provided between the valve flap and the flange, so the flange and the valve flap need to be removed to mount the spring, which makes the spring not easy to be replaced.
[0060] For the arrangement manner of the piston cylinder, preferably the valve stem 3 and the piston cylinder are designed to be vertically disposed when the valve body 1 is placed horizontally. The direction in which the piston cylinder is disposed can facilitate the infusion of damping medium, and there is no such a problem that the inclined piston cylinder shown in FIG. 1 is difficult to be filled up due to the inclination of the liquid surface. In addition, preferably an axis of the inlet and outlet of the first working chamber A coincides with an axis of the inlet and outlet of the second working chamber B, which is parallel to the plane on which the valve flap 2 is located. In combination with the lateral view of FIG. 3, it can be understood that not only the valve body itself is easy to manufacture, but also the sealing surface inside the valve is relatively easy to machine.
[0061] In order to ensure the sealing property between various combined components, a glyd ring and an 0-ring may be provided in the anti-pollution micro-resistance slow-closing check valve. A glyd ring is a sealing ring formed by combining a rubber 0-ring and a teflon ring, the friction is small with no creeping phenomenon and good static sealing performance, and it can be used safely in a medium containing dirt. In the check valve of the present disclosure, the glyd ring is mainly used for the sealing between movement contacts, for example, a glyd ring 9 is provided between the piston 20 and the cylinder body 21, and/or a glyd ring 4 is provided between the valve stem 3 and the flange 6. An 0-ring is a rubber sealing ring with a circular cross section, which mainly seals a liquid in a stationary state, for example, an 0-ring 22 is provided between the cylinder body 21 and the flange 6 and/or an 0-ring 5 is between the valve body 1 and the flange 6.
[0062] The isolation effect of the rubber membrane 17 has been mentioned earlier, and FIG. 2 shows a reference of the fixing method thereof. That is, the valve cover 13 is provided with a center hole through which a spring seat 15 is fitted, both ends of the spring 18 are respectively connected to the spring seat 15 and the piston 20, the spring seat 15 is sleeved with a spacer bush 16, and the rubber membrane 17 is clamped and fixed by the spring seat 15 and the spacer bush 16.
[0063] Based on the description of the aforementioned embodiments of the anti-pollution micro-resistance slow-closing check valve, the present disclosure also provides an industrial drainage system comprising a water pump and the aforementioned anti-pollution micro-resistance slow-closing check valve, wherein the anti-pollution micro-resistance slow-closing check valve is provided on the outlet side of the water pump, for preventing the impact of water backflow against the water pump, thereby forming a protective effect for the water pump.
[0064] Next, in combination with the structures of the specific embodiments of the anti-pollution micro-resistance slow-closing check valve shown in FIGS. 2-4, the main procedure of the application in the industrial drainage system is explained.
Firstly, it is needed to connect the anti-pollution micro-resistance slow-closing check valve into the industrial drainage system, connect the first working chamber A of the valve body 1 to the outlet side of the water pump, and connect the second working chamber B to the water using side. At the same time, damping medium (for example, hydraulic oil) needs to be infused into the piston cylinder of the anti-pollution type micro-resistance slow-closing check valve in advance, and one end of the pipeline is need to be connected with the valve cover 13 through the pipe joint 10, and the other end of the pipeline is connected with the second working chamber B through the pipe joint 7. In the original state, the piston 20, the valve stem 3 and the valve flap 2 are at the bottom position for closing the passage between the first working chamber A and the second working chamber B, under the action of the self weight thereof and the elastic force of the spring 18.
[0065] When the water pump is started, the water pumped by the pump enters the first working chamber A, and when a certain pressure is accumulated in the first working chamber A, the self weight of the piston 20, the valve stem 3 and the valve flap 2 and the elastic force of the spring 18 can be overcome thus lifting up the valve flap 2. At this opening initial stage, the cross-sectional dimension of the position on the guide rod 19 coinciding with the medium passage on the piston 18 is the same as the cross-sectional dimension of the medium passage, so that the hydraulic oil fails to pass through the medium passage. and it can only pass through the orifice and the cone stopper 11 on the other side, such that the hydraulic oil in the upper chamber of the piston 18 flows to the lower chamber at a relatively slow speed, so that opening of the valve flap 2 is carried out at a slow speed. This allows the flow velocity of the water pumped by the water pump not to change too fast and form water hammer against the drainage system.
[0066] After passing the opening initial stage, the piston 18 moves upwards and correspondingly the cross-sectional dimension of the position on the guide rod coinciding with the medium passage on the piston 18 is changed, i.e., both sides of the cylinder of the guide rod 17 are milled, making it smaller than the cross-sectional dimension of the medium passage. At this time, since the gap between the guide rod 19 and the medium passage is much larger than that the orifice and the cone stopper 11, the hydraulic oil in the upper chamber preferably flows from the gap to the lower chamber, so that the flow velocity of the hydraulic oil is increased, such that the piston 18 can quickly rise, thus making the valve flap quickly leave the closed position. When the acting force of water, the self weight of the piston 20, the valve stem 3 and the valve flap 2, and the elastic force of the spring 18 are balanced, the valve flap 2 stops rising and reaches the maximum opening degree. During rise of the valve flap, since the valve stem 3 occupies a certain volume in the inner chamber of the piston cylinder, it will cause an upward protrusion of the rubber membrane 17. When the valve flap 2 reaches the maximum opening degree, the water pumped by the water pump can substantially unimpededly pass through the check valve.
[0067] When emergencies such as blockage and sudden stop of the water pump happen to the industrial drainage system, and the water pressure on the water using side is higher than that on the pump side, backflow of water occurs. That is, water flows into the second working chamber B and then flows out of the first working chamber A. Since the pressure of the second working chamber B is greater than the pressure of the first working chamber A, a part of the backward water flows through the valve body 1 and another part enters the hollow chamber of the valve cover 13 through the pipeline 8 and acts on the rubber membrane 17 between the cylinder body 21 and the valve cover 13. The water acting on the rubber membrane 17 can transfer the motion state to the hydraulic oil in the piston chamber through the rubber membrane 17, the movement of the hydraulic oil then acts on the piston 20, and the valve flap 2 moves downwards under the combined action of water pressure of the valve flap 2, pressure of the hydraulic oil against the piston 20, the elastic force of the spring 18 and the self weight of the piston 20, the valve stem 3 and the valve flap 2.
[0068] In the initial stage of descending, the overlapping position of the guide rod 19 and the medium passage on the piston 18 is milled, such that it is smaller than the cross-sectional dimension of the medium passage, so that flow is preferably through the gap between the guide rod 19 and the medium passage. Due to the large flow area, the hydraulic oil flows relatively fast, such that the valve flap 2 rapidly descends. When the piston 20 is lowered to a certain height (corresponding to the closing end stage of the valve flap), since the rod structure of the overlapping position of the guide rod 19 and the medium passage on the piston 18 has completely filled up the medium passage, in the closing end stage of the valve core, the hydraulic oil can only flow through the orifice and the cone stopper 11, such that the hydraulic oil in the lower chamber of the piston 18 flows to the upper chamber at a relatively low speed, so that closing of the valve flap 2 is carried out at a slow speed. This allows the flow velocity of the water pumped by the water pump not to change too fast and form water hammer against the drainage system. When the valve flap 2 reaches the lowest position, the check valve is closed and the rubber membrane 17 returns to the initial state.
[0069] Finally, it should be explained that: the abovementioned embodiments are only used for explaining the technical solutions of the present disclosure instead of limiting the same; while the present disclosure has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that:
modifications can still be made to the embodiments of the present disclosure, or equivalent replacement can be made to part of the technical features thereof; and these modifications or replacement, not departing from the spirit of the technical solutions of the present disclosure, should all be contained in the scope of the technical solutions defined in the present disclosure.
Claims (18)
1. An anti-pollution micro-resistance slow-closing check valve, comprising:
a valve body, provided with a first working chamber and a second working chamber in communication with each other for working fluid medium passing through;
a valve flap;
a piston cylinder, mounted on one side of the valve body near the second working chamber, the piston cylinder is provided with a first medium chamber and a second medium chamber respectively on both sides of a piston within the piston cylinder and communicating with each other, the first medium chamber is in communication with the second working chamber;
a valve stem, both ends of which respectively connected with the valve flap and the piston, such that the piston, the valve stem and the valve flap move synchronously to close or open a communication passage between the first working chamber and the second working chamber;
and the first medium chamber is away from the valve stem, and the second medium chamber is near the valve stem;
a buffering mechanism, for buffering the piston; and a ductile spacer, provided within the first medium chamber, for isolating a damping medium within the piston cylinder and the working fluid medium from the second working chamber.
a valve body, provided with a first working chamber and a second working chamber in communication with each other for working fluid medium passing through;
a valve flap;
a piston cylinder, mounted on one side of the valve body near the second working chamber, the piston cylinder is provided with a first medium chamber and a second medium chamber respectively on both sides of a piston within the piston cylinder and communicating with each other, the first medium chamber is in communication with the second working chamber;
a valve stem, both ends of which respectively connected with the valve flap and the piston, such that the piston, the valve stem and the valve flap move synchronously to close or open a communication passage between the first working chamber and the second working chamber;
and the first medium chamber is away from the valve stem, and the second medium chamber is near the valve stem;
a buffering mechanism, for buffering the piston; and a ductile spacer, provided within the first medium chamber, for isolating a damping medium within the piston cylinder and the working fluid medium from the second working chamber.
2. "I he anti-pollution micro-resistance slow-closing check valve according to claim 1, wherein the buffering mechanism comprises a throttle mechanism provided within the piston cylinder, and communicating the first medium chamber and the second medium chamber, for throttling the damping medium passing therethrough.
3. The anti-pollution micro-resistance slow-closing check valve according to claim 2, wherein the throttle mechanism comprises an orifice and a cone stopper provided in the piston, the first medium chamber and the second medium chamber are in communication through the orifice, and the cone stopper is provided in the orifice, for throttling the damping medium passing therethro ugh.
4. The anti-pollution micro-resistance slow-closing check valve according to claim 2, wherein the buffering mechanism further comprising a medium passage provided within the piston cylinder, for providing communication between the first rnedium chamber and the second medium chamber, the medium passage is further provided with an on-off mechanism for connecting or disconnecting the medium passage.
5. The anti-pollution micro-resistance slow-closing check valve according to claim 4, wherein the on-off mechanism is configured to disconnect the medium passage during the opening initial stage, or during the closing end stage, or during both the opening initial stage and the closing end stage of the valve flap, and connect the medium passage during other movement stages of the valve flap.
6. The anti-pollution micro-resistance slow-closing check valve according to claim 4, wherein the on-off mechanism is a stroke-based on-off switch.
7. The anti-pollution micro-resistance slow-closing check valve according to clairn 6, wherein the medium passage is set in the piston, the piston cylinder is provided therein with a guide rod fixed with respect to the piston cylinder, and the guide rod is inserted in the medium passage, the cross-sectional dimension of the guide rod changes in the direction of length;
durinQ a first predetermined stroke of the piston, the cross-sectional dimension on the guide rod corresponding to a current position of the piston is less than the cross-sectional dimension of the medium passage, such that the damping media within the mediurn chambers on both sides of the piston flow through a gap between the guide rod and the medium passage;
and during the second predetermined stroke of the piston, the cross-sectional dimension on the guide rod corresponding to the current position of the piston is equivalent to the cross-sectional dimension of the medium passage, such that the damping media within the first medium chamber and the second medium chamber fail to pass through the medium passage.
durinQ a first predetermined stroke of the piston, the cross-sectional dimension on the guide rod corresponding to a current position of the piston is less than the cross-sectional dimension of the medium passage, such that the damping media within the mediurn chambers on both sides of the piston flow through a gap between the guide rod and the medium passage;
and during the second predetermined stroke of the piston, the cross-sectional dimension on the guide rod corresponding to the current position of the piston is equivalent to the cross-sectional dimension of the medium passage, such that the damping media within the first medium chamber and the second medium chamber fail to pass through the medium passage.
8. The anti-pollution micro-resistance slow-closing check valve according to clairn 1, wherein the spacer is a rubber membrane, for extending or deforming towards the inside or outside of the piston cylinder with the change of the pressure relationship between the damping rnedium in the piston cylinder and the working fluid medium from the second working chamber.
9. The anti-pollution micro-resistance slow-closing check valve according to claim 1, wherein the piston cylinder comprises a cylinder body, a valve cover and the piston, the cylinder body is mounted on the valve body by means of a flange, the valve cover is mounted on one side of the cylinder body away from the valve stem, the spacer is provided on the inner side of the valve cover, and a space between the valve cover and the spacer is in communication with the second working chamber.
10. The anti-pollution micro-resistance slow-closing check valve according to claim 9, wherein a hollow inner chamber is provided on the inner side of the valve cover, and the hollow inner chamber and the second working chamber are in communication by means of a pipeline.
11. The anti-pollution micro-resistance slow-closing check valve according to claim 10, wherein a filter is provided in one side of the pipeline near the second working chamber.
12. The anti-pollution micro-resistance slow-closing check valve according to claim 9, wherein a spring is provided between the valve cover and the piston, and the spring is soaked in the damping medium within the piston cylinder.
13. The anti-pollution micro-resistance slow-closing check valve according to claim 1, wherein the damping medium in the piston cylinder is hydraulic oil.
14. The anti-pollution micro-resistance slow-closing check valve according to claim 1, wherein the valve stem and the piston cylinder are set vertically when the valve body is disposed in a horizontal state.
15. The anti-pollution micro-resistance slow-closing check valve according to claim 14, wherein an axis of an inlet and an outlet of the first working chamber coincides with an axis of an inlet and an outlet of the second working chamber, and is parallel to a plane on which the valve flap is located.
16. The anti-pollution micro-resistance slow-closing check valve according to claim 9, further comprising:
a glyd ring, provided between the piston and the cylinder body and/or between the valve stem and the flange; and an 0-ring, provided between the cylinder body and the flange and/or between the valve body and the flange
a glyd ring, provided between the piston and the cylinder body and/or between the valve stem and the flange; and an 0-ring, provided between the cylinder body and the flange and/or between the valve body and the flange
17. The anti-pollution micro-resistance slow-closing check valve according to claim 12, wherein the spacer is a rubber membrane, the valve cover is provided with a center hole through which a spring seat is fitted, both ends of the spring are respectively connected to the spring seat and the piston, the spring seat is sleeved with a spacer bush, and the rubber membrane is clamped between the spring seat and the spacer bush.
18. An industrial drainage system, comprising a water pump and an anti-pollution micro-resi stance slow-closing check valve according to claim 1, the anti-pollution micro-resistance slow closing check valve is provided on an outlet side of the water pump.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/CN2016/100552 WO2018058364A1 (en) | 2016-09-28 | 2016-09-28 | Contamination-preventing micro-resistance slow-closing check valve and industrial drainage system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA3042108A1 CA3042108A1 (en) | 2018-04-05 |
| CA3042108C true CA3042108C (en) | 2020-04-07 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA3042108A Active CA3042108C (en) | 2016-09-28 | 2016-09-28 | Anti-pollution micro-resistance slow-closing check valve and industrial drainage system |
Country Status (4)
| Country | Link |
|---|---|
| AU (1) | AU2016424703B2 (en) |
| CA (1) | CA3042108C (en) |
| IL (1) | IL259594B2 (en) |
| WO (1) | WO2018058364A1 (en) |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69511430D1 (en) * | 1994-12-05 | 1999-09-16 | Yokota Seisakusho Hiroshima Kk | CHECK VALVE TO PREVENT WATER SHOCK |
| CN2399577Y (en) * | 1999-11-24 | 2000-10-04 | 刘庆 | Self-control silencing check valve |
| CN2423461Y (en) * | 2000-05-17 | 2001-03-14 | 上海正丰阀门制造有限公司 | Piston-type buffer close check valve |
| JP5208396B2 (en) * | 2006-10-10 | 2013-06-12 | 株式会社荏原製作所 | Vacuum sewer valve, vacuum sewer system |
| CN102410203B (en) * | 2011-10-25 | 2014-08-27 | 太原理工大学 | Hydraulic slow-resistance water pump valve for drainage system under coal mine |
| CN103542142B (en) * | 2012-07-11 | 2016-03-09 | 上海神通企业发展有限公司 | A kind of self-powering type safety check |
| CN203286063U (en) * | 2013-06-08 | 2013-11-13 | 正丰阀门集团有限公司 | Slowly-closed mute axial-flow type check valve |
| US9360133B2 (en) * | 2014-10-14 | 2016-06-07 | Kennedy Valve Company | Cushioned check valve |
| CN204922108U (en) * | 2015-09-15 | 2015-12-30 | 明珠阀门集团有限公司 | Vertical check valve of closed is delayed in liquid accuse |
-
2016
- 2016-09-28 AU AU2016424703A patent/AU2016424703B2/en not_active Ceased
- 2016-09-28 WO PCT/CN2016/100552 patent/WO2018058364A1/en active Application Filing
- 2016-09-28 CA CA3042108A patent/CA3042108C/en active Active
-
2018
- 2018-05-24 IL IL259594A patent/IL259594B2/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| WO2018058364A1 (en) | 2018-04-05 |
| IL259594A (en) | 2018-07-31 |
| AU2016424703A1 (en) | 2019-05-16 |
| AU2016424703B2 (en) | 2020-09-17 |
| CA3042108A1 (en) | 2018-04-05 |
| IL259594B1 (en) | 2023-04-01 |
| IL259594B2 (en) | 2023-08-01 |
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Effective date: 20190429 |