CN220354553U

CN220354553U - Low resistance backflow preventer

Info

Publication number: CN220354553U
Application number: CN202321714570.8U
Authority: CN
Inventors: 戴雪洁
Original assignee: Wenzhou Jinchuan Valve Co ltd
Current assignee: Wenzhou Jinchuan Valve Co ltd
Priority date: 2023-06-30
Filing date: 2023-06-30
Publication date: 2024-01-16
Anticipated expiration: 2033-06-30

Abstract

The utility model discloses a low-resistance backflow preventer, which comprises a main valve and a water drain valve, wherein two ends of the water drain valve are respectively connected with an inlet end and an outlet end of the main valve through a front main control pipe and a rear main control pipe of the valve, and the side part of the water drain valve is communicated with an inner cavity of the main valve through a water drain pipe; the main valve comprises a valve body, a front valve sleeve, a rear valve sleeve, a valve rod, a front valve clack, a rear valve clack and a check spring, wherein the front valve sleeve and the rear valve sleeve are respectively arranged at an inlet end and an outlet end of the valve body, a partition plate is arranged at the inner end of the rear valve sleeve, a first guide hole matched with the valve rod is formed in the center of the partition plate, the front valve clack and the rear valve clack are mounted on the valve rod in a linkage mode, the front valve clack is arranged between the front valve sleeve and the rear valve sleeve, the rear valve clack is arranged in the rear valve sleeve, a plurality of through holes are formed in the side portion of the rear valve sleeve, and the check spring is arranged between the front valve clack and the rear valve sleeve. The utility model has simpler and more reliable structure and very convenient disassembly and assembly, and is beneficial to the rapid assembly in the early stage and the maintenance operation in the later stage.

Description

Low resistance backflow preventer

Technical Field

The utility model relates to the technical field of valves, in particular to a low-resistance backflow preventer.

Background

The backflow preventer is also called as a sewage blocking valve, is a safety device for strictly preventing a water source from being polluted when a domestic drinking water pipeline is in backflow, and can also be applied to other pipeline systems which do not allow mediums to flow backwards. Patent publication No. CN204961930U discloses a low resistance backflow preventer, which uses the pressure reduction of medium flowing through a water inlet check valve due to the set small mechanical resistance and the loss of a water passing head, so that the inlet pressure is higher than the pressure of a water draining valve cavity, and the pressure difference DeltaP controls the closing of the water draining valve, thereby ensuring the normal water supply between the inlet and the outlet. The safety value DeltaP is set to be 0.005MPa, and once the safety value DeltaP is smaller than the safety value, the medium is in a critical state of backflow, at the moment, the spring of the water drain valve automatically opens the water drain valve to drain the backflow water in the valve cavity. The water draining valve adopts a double-flow-passage structure, so that a large amount of air is supplemented into the valve cavity while water is drained, an air partition is formed, medium backflow is stopped, and siphon backflow is effectively prevented. At the moment, the pressure in the valve cavity of the water escape valve is reduced, and when the delta P reaches a set safety value, the water escape valve is automatically closed. The backflow preventer of this structure is complicated in structure, and spare part is more, and its use cost is high, and the dismouting is inconvenient moreover, is unfavorable for earlier stage fast assembly and later maintenance operation.

Disclosure of Invention

The utility model aims to provide a low-resistance backflow preventer, which has a simpler and more reliable structure and is very convenient to assemble and disassemble, thereby being beneficial to the rapid assembly in the early stage and the maintenance operation in the later stage.

In order to achieve the above purpose, the present utility model provides the following technical solutions: the low-resistance backflow preventer comprises a main valve and a water drain valve, wherein two ends of the water drain valve are respectively connected with an inlet end and an outlet end of the main valve through a front main control pipe and a rear main control pipe of the valve, the side part of the water drain valve is communicated with an inner cavity of the main valve through a water drain pipe, and a water drain port communicated with the atmosphere is arranged at the lower part of the water drain valve; the main valve comprises a valve body, a front valve sleeve, a rear valve sleeve, a valve rod, a front valve clack, a rear valve clack and a check spring, wherein the front valve sleeve and the rear valve sleeve are respectively arranged at an inlet end and an outlet end of the valve body, a partition plate is arranged at the inner end of the rear valve sleeve, a first guide hole matched with the valve rod is formed in the center of the partition plate, the front valve clack and the rear valve clack are mounted on the valve rod in a linkage mode, the front valve clack is in a disc shape and is arranged between the front valve sleeve and the rear valve sleeve, the rear valve clack is in a sleeve shape and is arranged in the rear valve sleeve in a sliding mode, a plurality of through holes are formed in the side portion of the rear valve sleeve, and the check spring is arranged between the front valve clack and the rear valve sleeve, so that when the pressure of the inlet end of the valve body is smaller than that the pressure of the outlet end, the front valve clack abuts against the inner end of the front valve sleeve, and the rear valve clack blocks the through holes.

By adopting the technical scheme, when the medium positively flows, the pressure of the inlet end of the main valve is larger than that of the outlet end, the front valve clack and the rear valve clack are both opened, the medium flows through the inner cavity of the valve body from the inlet end and flows out from the outlet end, and simultaneously, a positive pressure difference is generated between the inlet and the outlet so that the water discharge valve is closed and does not discharge water; when the pressure of the outlet end of the main valve is greater than that of the inlet end, the front valve clack and the rear valve clack are automatically closed under the action of water flow and a check spring, and meanwhile, the reverse pressure difference generated between the inlet and the outlet enables the water discharge valve to be opened, and the maximum discharge amount is maintained, so that the inner cavity of the valve body of the main valve is communicated with the atmosphere to form an air partition, the backflow water is cut off to pollute the inlet end, and the anti-fouling partition function is realized. Compared with the prior art, the novel hydraulic pressure control device has the advantages of fewer parts, simpler and more reliable structure and very convenient disassembly and assembly, and is beneficial to early-stage rapid assembly and later-stage maintenance operation.

The utility model is further characterized in that a first step and a first thread section are arranged on the periphery of the valve rod, a first lock nut is connected to the first thread section in a threaded mode, the front valve clack is pressed on the first step when the first lock nut is screwed, and a first gasket is arranged between the first lock nut and the front valve clack.

Through adopting above-mentioned technical scheme, can realize the quick assembly of preceding valve clack and valve rod, connection structure is simple reliable, and the dismouting is very convenient.

The utility model is further characterized in that a valve sleeve supporting part is arranged in the front valve sleeve, a second guide hole matched with the valve rod is formed in the center of the valve sleeve supporting part, and a plurality of front guide holes are distributed on the valve sleeve supporting part in a circumferential array.

Through adopting above-mentioned technical scheme, not only can guarantee the normal circulation of front valve barrel fluidic, can further play support and direction to the valve rod moreover, promote the stability of valve rod motion.

The utility model is further characterized in that a valve clack supporting part is arranged in the rear valve clack, a third guide hole matched with the valve rod is formed in the center of the valve clack supporting part, and a plurality of rear guide holes are distributed on the valve clack supporting part in a circumferential array.

Through adopting above-mentioned technical scheme, when can guaranteeing that the back valve clack is opened, fluid can pass from the valve clack centre, plays the effect that both ends switched on.

The valve rod is further provided with a second step and a second thread section, the second thread section is connected with a second lock nut in a threaded mode, when the second lock nut is screwed, a valve clack supporting part on the rear valve clack is pressed on the second step, and a second gasket is arranged between the second lock nut and the rear valve clack.

Through adopting above-mentioned technical scheme, can realize the quick assembly of back valve clack and valve rod, connection structure is simple reliable, and the dismouting is very convenient.

The utility model further provides that a pre-tightening spring is clamped between the second gasket and the valve clack supporting part.

Through adopting above-mentioned technical scheme, because valve clack supporting part is in the back valve clack, not good to the operation of screwing of second lock nut, through the pretension spring transition, make the second lock nut set up outside the valve clack behind can, compress tightly valve clack supporting part by the pretension spring, can reach the effect of valve clack after the restriction equally, do benefit to the dismouting operation.

The utility model is further characterized in that the front valve clack is made of silicon rubber, and a sealing ring used for sealing and matching with the inner periphery of the rear valve sleeve is arranged on the outer periphery of the rear valve clack.

By adopting the technical scheme, the sealing performance of the main valve can be improved when the main valve is closed, and leakage of a medium from a gap between the front valve clack and the front valve sleeve or a gap between the rear valve clack and the rear valve sleeve is avoided.

The utility model is further arranged that the outer periphery of the front valve sleeve is in threaded fit with the inner periphery of the inlet end of the valve body, the outer end of the front valve sleeve is provided with a first limit flange which extends outwards and is used for being abutted against the outer end face of the inlet of the valve body, the outer periphery of the rear valve sleeve is in threaded fit with the inner periphery of the outlet end of the valve body, and the outer end of the rear valve sleeve is provided with a second limit flange which extends outwards and is used for being abutted against the outer end face of the outlet of the valve body.

Through adopting above-mentioned technical scheme, the dismouting is very convenient, simultaneously, and the design of each limit flange can be to preceding valve pocket and back valve pocket installation spacing, promotes the installation accuracy.

Drawings

FIG. 1 is a perspective view of the whole of the present utility model;

FIG. 2 is an enlarged schematic view of the portion A in FIG. 1;

fig. 3 is an enlarged schematic view of the portion B in fig. 1.

In the figure: 1. a main valve; 2. a water drain valve; 3. a valve front main control pipe; 4. a valve back main control pipe; 5. a drain pipe; 6. a water discharge port; 7. a valve body; 8. a front valve sleeve; 9. a rear valve sleeve; 10. a valve stem; 11. a front valve flap; 12. a rear valve flap; 13. a check spring; 14. a partition plate; 15. a first guide hole; 16. a via hole; 17. a first step; 18. a first thread segment; 19. a first lock nut; 20. a first gasket; 21. a valve sleeve support part; 22. a second guide hole; 23. a front deflector hole; 24. a valve flap support; 25. a third guide hole; 26. a rear deflector hole; 27. a second step; 28. a second thread segment; 29. a second lock nut; 30. a second gasket; 31. a pre-tightening spring; 32. a seal ring; 33. a first limit flange; 34. and a second limit flange.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Examples: the low resistance backflow preventer as shown in figures 1-3 comprises a main valve 1 and a water drain valve 2, wherein two ends of the water drain valve 2 are respectively connected with an inlet end and an outlet end of the main valve 1 through a front main control pipe 3 and a rear main control pipe 4, the upper part of the water drain valve 2 is communicated with an inner cavity of the main valve 1 through a water drain pipe 5, a water drain port 6 communicated with the atmosphere is arranged at the lower part of the water drain valve 2, and the water drain valve 2 is a drainer and is a conventional device and is easily purchased in the market, so that the specific structure of the water drain valve is not described in detail herein; the main valve 1 comprises a valve body 7, a front valve sleeve 8, a rear valve sleeve 9, a valve rod 10, a front valve clack 11, a rear valve clack 12 and a check spring 13, wherein the front valve sleeve 8 and the rear valve sleeve 9 are respectively arranged at an inlet end and an outlet end of the valve body 7, the front valve sleeve 8 and the rear valve sleeve 9 are coaxially arranged, a sealing ring 32 is arranged between the front valve sleeve 8 and the inlet end of the valve body 7, a sealing ring 32 is arranged between the rear valve sleeve 9 and the outlet end of the valve body 7, a partition 14 is arranged at the inner end of the rear valve sleeve 9, a first guide hole 15 matched with the valve rod 10 is formed in the center of the partition 14, the front valve clack 11 and the rear valve clack 12 are mounted on the valve rod 10 in a linkage manner, the front valve clack 11 is in a disc shape and is arranged between the front valve sleeve 8 and the rear valve sleeve 9, the rear valve clack 12 is arranged in the rear valve sleeve 9 in a sliding manner, the periphery of the rear valve clack 12 is tightly attached to the inner periphery of the rear valve sleeve 9, a plurality of through holes 16 are formed in the side of the rear valve sleeve 9, the check spring 13 is arranged between the front valve clack 11 and the rear valve sleeve 9, and the inlet pressure of the front valve clack 7 is smaller than the outlet pressure of the valve 11, and the front valve clack 12 is tightly blocked by the inner end of the front inner end of the valve clack 12 when the front valve clack 11 abuts against the front inner end of the front valve clack 12. When the medium flows positively, the pressure of the inlet end of the main valve 1 is larger than the pressure of the outlet end, the front valve clack 11 and the rear valve clack 12 are both opened, the medium flows through the inner cavity of the valve body 7 from the inlet end and flows out from the outlet end, and meanwhile, a positive pressure difference is generated between the inlet and the outlet so that the water drain valve 2 is closed and does not drain water; when the pressure of the outlet end of the main valve 1 is greater than that of the inlet end, the front valve clack 11 and the rear valve clack 12 are automatically closed under the action of water flow and a check spring 13, and meanwhile, the water discharge valve 2 is opened by the reverse pressure difference generated between the inlet and the outlet, and the maximum discharge amount is maintained, so that the inner cavity of the valve body 7 of the main valve 1 is communicated with the atmosphere to form an air partition, the backflow water is cut off to pollute the inlet end, and the anti-fouling partition function is realized. Compared with the prior art, the novel hydraulic pressure control device has the advantages of fewer parts, simpler and more reliable structure and very convenient disassembly and assembly, and is beneficial to early-stage rapid assembly and later-stage maintenance operation.

That is, the front valve sleeve 8 has a hollow shape with two open ends, the rear valve sleeve 9 has a shape with one open end and one closed end, and the closed end is provided with a first guide hole 15.

As shown in fig. 1 and fig. 2, the outer periphery of the valve rod 10 is provided with a first step 17 and a first thread section 18, the first thread section 18 is in threaded connection with a first lock nut 19, the front valve clack 11 is pressed on the first step 17 when the first lock nut 19 is screwed, and a first gasket 20 is arranged between the first lock nut 19 and the front valve clack 11. The design can realize the rapid assembly of the front valve clack 11 and the valve rod 10, and the connecting structure is simple and reliable, and the disassembly and the assembly are very convenient.

As shown in fig. 1, a valve sleeve supporting portion 21 is disposed in the front valve sleeve 8, a second guide hole 22 matched with the valve rod 10 is formed in the center of the valve sleeve supporting portion 21, the optical axis portion of the valve rod 10 is matched with the second guide hole 22, and a plurality of front guide holes 23 are distributed on the valve sleeve supporting portion 21 in a circumferential array. The design not only can ensure the normal circulation of the fluid of the front valve sleeve 8, but also can further support and guide the valve rod 10, thereby improving the stability of the movement of the valve rod 10.

As shown in fig. 1, a valve clack supporting part 24 is disposed in the rear valve clack 12, a third guide hole 25 matched with the valve rod 10 is disposed in the center of the valve clack supporting part 24, and a plurality of rear diversion holes 26 are distributed on the valve clack supporting part 24 in a circumferential array. By the design, when the rear valve clack 12 is opened, fluid can pass through the middle of the valve clack, and the effect of conducting at two ends is achieved.

As shown in fig. 1 and fig. 3, the valve rod 10 is further provided with a second step 27 and a second threaded section 28, the second threaded section 28 is connected with a second lock nut 29 in a threaded manner, when the second lock nut 29 is screwed, the valve clack supporting part 24 on the rear valve clack 12 is pressed on the second step 27, and a second gasket 30 is arranged between the second lock nut 29 and the rear valve clack 12. The design can realize the rapid assembly of the rear valve clack 12 and the valve rod 10, and the connecting structure is simple and reliable, and the disassembly and assembly are very convenient.

As shown in fig. 3, a pre-tightening spring 31 is interposed between the second spacer 30 and the valve flap supporting portion 24. Because the valve clack supporting part 24 is arranged in the rear valve clack 12, the screwing operation of the second lock nut 29 is not easy, the second lock nut 29 is arranged outside the rear valve clack 12 through the transition of the pre-tightening spring 31, the pre-tightening spring 31 compresses the valve clack supporting part 24, the effect of limiting the rear valve clack 12 can be achieved, and the disassembly and assembly operations are facilitated.

As shown in fig. 1, the front valve clack 11 is made of silicone rubber, and a sealing ring 32 for forming sealing fit with the inner periphery of the rear valve sleeve 9 is arranged on the outer periphery of the rear valve clack 12. This design can promote the sealing performance of the main valve 1 when closed, avoiding medium leakage from the gap between the front valve flap 11 and the front valve sleeve 8 or from the gap between the rear valve flap 12 and the rear valve sleeve 9.

As shown in fig. 1, the outer periphery of the front valve sleeve 8 is in threaded fit with the inner periphery of the inlet end of the valve body 7, namely, the outer periphery of the front valve sleeve 8 is provided with an external thread, the inner periphery of the inlet end of the valve body 7 is provided with an internal thread matched with the external thread, the outer periphery of the front valve sleeve 8 is provided with a first limit flange 33 which extends outwards and is used for being abutted against the outer end face of the inlet end of the valve body 7, the outer periphery of the rear valve sleeve 9 is in threaded fit with the inner periphery of the outlet end of the valve body 7, namely, the outer periphery of the rear valve sleeve 9 is provided with an external thread matched with the external thread, and the outer periphery of the rear valve sleeve 9 is provided with a second limit flange 34 which extends outwards and is used for being abutted against the outer end face of the outlet end of the valve body 7. The design dismouting is very convenient, and simultaneously, the design of each limit flange can be to preceding valve pocket 8 and back valve pocket 9 installation spacing, promotes the installation accuracy.

Claims

1. The low-resistance backflow preventer comprises a main valve (1) and a water drain valve (2), wherein two ends of the water drain valve (2) are respectively connected with an inlet end and an outlet end of the main valve (1) through a main control pipe (3) in front of the valve and a main control pipe (4) behind the valve, the side part of the water drain valve (2) is communicated with an inner cavity of the main valve (1) through a water drain pipe (5), and a water drain port (6) communicated with the atmosphere is arranged at the lower part of the water drain valve (2); the method is characterized in that: the main valve (1) comprises a valve body (7), a front valve sleeve (8), a rear valve sleeve (9), a valve rod (10), a front valve clack (11), a rear valve clack (12) and a check spring (13), wherein the front valve sleeve (8) and the rear valve sleeve (9) are respectively arranged at the inlet end and the outlet end of the valve body (7), a partition plate (14) is arranged at the inner end of the rear valve sleeve (9), a first guide hole (15) matched with the valve rod (10) is formed in the center of the partition plate (14), the front valve clack (11) and the rear valve clack (12) are mounted on the valve rod (10) in a linkage mode, the front valve clack (11) is in a disc shape and is arranged between the front valve sleeve (8) and the rear valve sleeve (9), the rear valve clack (12) is in a sleeve shape and is arranged in the rear valve sleeve (9) in a sliding mode, a plurality of through holes (16) are formed in the side portion of the rear valve sleeve (9), and the check spring (13) is arranged between the front valve clack (11) and the rear valve sleeve (9) so that when the pressure at the inlet end of the valve body (7) is smaller than the outlet pressure, the front valve clack (11) and the inner end of the valve clack (12) is blocked at the front.

2. The low-resistance backflow preventer of claim 1, wherein: the valve rod is characterized in that a first step (17) and a first thread section (18) are arranged on the periphery of the valve rod (10), a first lock nut (19) is connected to the first thread section (18) in a threaded mode, when the first lock nut (19) is screwed, the front valve clack (11) is pressed on the first step (17), and a first gasket (20) is arranged between the first lock nut (19) and the front valve clack (11).

3. The low-resistance backflow preventer of claim 1, wherein: the inside of preceding valve pocket (8) is equipped with valve pocket supporting part (21), valve pocket supporting part (21) center offer with valve rod (10) matched with second guide hole (22) to be distributed in a plurality of preceding water conservancy diversion holes (23) of circumference array on valve pocket supporting part (21).

4. The low-resistance backflow preventer of claim 1, wherein: the valve is characterized in that a valve clack supporting part (24) is arranged in the rear valve clack (12), a third guide hole (25) matched with the valve rod (10) is formed in the center of the valve clack supporting part (24), and a plurality of rear diversion holes (26) are distributed on the valve clack supporting part (24) in a circumferential array.

5. The low-resistance backflow preventer of claim 4, wherein: the valve rod (10) is further provided with a second step (27) and a second threaded section (28), the second threaded section (28) is connected with a second lock nut (29) in a threaded mode, when the second lock nut (29) is screwed, the valve clack supporting part (24) on the rear valve clack (12) is pressed on the second step (27), and a second gasket (30) is arranged between the second lock nut (29) and the rear valve clack (12).

6. The low-resistance backflow preventer of claim 5, wherein: a pre-tightening spring (31) is clamped between the second gasket (30) and the valve clack supporting part (24).

7. The low-resistance backflow preventer of claim 1, wherein: the front valve clack (11) is made of a silicon rubber material, and a sealing ring (32) used for being in sealing fit with the inner periphery of the rear valve sleeve (9) is arranged on the outer periphery of the rear valve clack (12).

8. The low-resistance backflow preventer of claim 1, wherein: the periphery of the front valve sleeve (8) is in threaded fit with the inner periphery of the inlet end of the valve body (7), a first limit flange (33) which extends outwards and is used for being abutted against the outer end face of the inlet of the valve body (7) is arranged at the outer end of the front valve sleeve (8), the periphery of the rear valve sleeve (9) is in threaded fit with the inner periphery of the outlet end of the valve body (7), and a second limit flange (34) which extends outwards and is used for being abutted against the outer end face of the outlet of the valve body (7) is arranged at the outer end of the rear valve sleeve (9).