CN211231721U - Backflow preventer with annular built-in drainer - Google Patents

Abstract

The utility model relates to a backflow preventer with an annular built-in drainer, which comprises a valve body. The inside of the valve body is sequentially provided with a cylindrical drain sealing piston and a water inlet valve from front to back along the direction from a water inlet to a water outlet. Disc and outlet valve disc; a pre-tightening spring is arranged between the drainage sealing piston and the front inner end face of the valve body, a main spring is arranged between the outlet valve disc and the rear inner end face of the valve body, and the middle part of the drainage sealing piston and the outlet valve disc is There is a water passage hole coaxially; the water inlet valve disc is coaxially penetrated on the guide sleeve inside the valve body and has a limit step at the front end, and the front and rear outer diameters of the water inlet valve disc are larger than the water passage hole for sliding The outer circumference of the guide sleeve is an annular valve channel, the outer circumference of the front end of the valve channel is an annular drain channel and is separated by a cylindrical wall, and the circumference of the drain channel is provided with a drainage sealing piston to move the top A drain port that is closed when connecting to the front end of the cylinder wall. The structure of the backflow preventer with the annular built-in drain is simple.

Description

Backflow preventer with annular built-in drain

technical field

The utility model relates to a backflow preventer with an annular built-in drain.

Background technique

At the terminal of the tap water supply pipeline, there are multiple faucets connected to the water pipeline of each family, as well as water heaters, washing machines, toilet tanks and other water appliances. When these water appliances are turned off, water still remains in the inner cavity and the pipeline. , If it is not opened for a long time, these stagnant water will breed a lot of bacteria, and if you use water utensils that do not meet drinking water standards, it will also produce rusty sewage. When an abnormal state occurs in the tap water pipe network in a certain area, for example, when the water supply pipe bursts or the main water is closed, the accumulated water in the cavity of the faucet and other water appliances will flow back into the In the drinking water pipe network in the district, it has caused large-scale pollution of drinking water sources in the district and seriously damaged people's health.

Due to the small diameter of the terminal pipe, the valve is generally connected by a threaded pipe. At present, a single check valve or a two-stage check valve is generally used to prevent the backflow of water. Although the check valve can prevent the backflow of water to a certain extent, it cannot prevent the backflow of water. Pollution, because the check valve may cause instantaneous water pollution during the closing time.

The backflow preventer is an effective device for preventing water backflow pollution in pipeline water supply. Due to space constraints, the current backflow preventer for screw thread connection adopts a diaphragm type with a built-in drain, but the diaphragm type has a short service life and is easily damaged, causing the drain to leak water, resulting in leakage of the valve.

Utility model content

In view of the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a backflow preventer with an annular built-in drain, which is not only simple in structure, but also convenient and efficient.

In order to solve the above-mentioned technical problems, the technical solution of the present utility model is: a backflow preventer with an annular built-in drain, comprising a valve body, and the inside of the valve body is sequentially provided with a circle along the direction from the water inlet to the water outlet. Cylindrical drainage sealing piston, water inlet valve disc, water outlet valve disc;

A pre-tightening spring is arranged between the drainage sealing piston and the front inner end face of the valve body, a main spring is arranged between the water outlet valve disc and the rear inner end face of the valve body, and the middle part of the drainage sealing piston and the water outlet valve disc is coaxially provided with a water passage. through hole;

The inlet valve disc is coaxially penetrated on the guide sleeve inside the valve body, and the front end is provided with a limit step.

The outer circumference of the guide sleeve is an annular valve channel, and the outer circumference of the front end of the valve channel is an annular drain channel and is separated by the cylindrical wall. Make closed drains.

Preferably, a filter screen is arranged in front of the water passage hole of the drainage sealing piston, and a rubber-lined sealing ring is provided on the rear end surface of the drainage sealing piston to abut against the front end of the water inlet valve flap to seal the water passage hole.

Preferably, the rear end surface of the water inlet valve flap is provided with a rubber-lined gasket, which is used to abut against the front end of the water outlet valve flap to seal the water passage hole.

Preferably, an O-shaped rubber sealing ring is provided between the drain sealing piston and the drain channel.

Preferably, the drainage sealing piston is located in the drainer channel inside the valve body, and the water inlet valve flap and the water outlet valve flap are located in the valve channel inside the valve body.

Preferably, an O-shaped rubber sealing ring is provided between the outlet valve flap and the valve channel.

Preferably, the valve body is composed of a backflow preventer valve body and a drainer valve body, the drainer valve body is screwed on the outer periphery of the front end of the backflow preventer valve body, and the water inlet valve disc and the water outlet valve disc are located inside the backflow preventer valve body. The drain sealing piston is located in the drainer channel inside the drainer valve body, and the cylindrical wall used to separate the valve channel and the drainer channel is the front end of the backflow preventer valve body.

Compared with the prior art, the utility model has the following beneficial effects:

Normal water supply state: when the pressure of the water inlet is greater than the pressure of the middle cavity, the pressure of the middle cavity is greater than the pressure of the water outlet, the pressure pushes the drainage sealing piston to seal the built-in annular drain, the drainage outlet is closed, the inlet valve flap moves back to the limit, and the outlet valve flap Move backward to the limit, the double-stage check is in a fully open state, and the water medium flows from the water inlet, to the middle cavity, and to the water outlet, and the water is supplied normally.

Double-stage check seal, open drain state: when the pressure of the water inlet decreases, the pressure of the water outlet is greater than the pressure of the water inlet, the water outlet disc moves towards the water inlet under the action of the main spring, seals with the water inlet disc, and at the same time with the inlet The water valve disc pushes the drainage sealing piston in the direction of the water inlet together, and the water inlet valve disc is sealed with the drainage sealing piston. Under the joint promotion of the outlet medium pressure and the main spring force, it provides a sufficient sealing specific pressure and forms an effective seal with the valve seat. To achieve double sealing to prevent water from flowing backwards, and at the same time, the drainage sealing piston leaves the annular built-in drainer, and the drain opening is opened, and the water that flows back instantaneously is discharged from the drain outlet and out of the valve.

It adopts hydraulic automatic control valve opening and closing technology, with annular built-in drainer and drain sealing piston. The amount is large, which meets the use requirements of the terminal water supply backflow preventer.

Since the valve disc sealing force of the two non-return devices is realized by self-actuated induction outlet pressure, the sealing force of the two non-return devices is greatly enhanced and the sealing is reliable. Even if the two sealing pairs are damaged, the leakage is very small, and it is quickly discharged by the drain to ensure the safety of drinking water.

The present utility model will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Description of drawings

Figure 1 is a schematic structural diagram of a normal water supply state.

Fig. 2 is a schematic diagram of the structure of the double-stage check seal and the drain state when the drainer is opened.

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2 .

Detailed ways

In order to make the above-mentioned features and advantages of the present utility model more obvious and easy to understand, the following specific embodiments are given and the accompanying drawings are described in detail as follows.

As shown in Figure 1-3, a backflow preventer with annular built-in drain includes a valve body 1, and the inside of the valve body is sequentially provided with cylindrical Drainage sealing piston 4, water inlet valve disc 5, water outlet valve disc 6;

A pre-tightening spring 7 is arranged between the drainage sealing piston and the front inner end face of the valve body, a main spring 8 is arranged between the water outlet valve disc and the rear inner end face of the valve body, and the drain sealing piston and the middle of the outlet valve disc are coaxially provided with water through hole 9;

The water inlet valve disc is coaxially penetrated on the guide sleeve 10 inside the valve body, and the front end is provided with a limit step 11, and the front and rear outer diameters of the water inlet valve disc are larger than the water passage holes for sliding and sealing the water passage holes;

The outer circumference of the guide sleeve is an annular valve channel 12, and the outer circumference of the guide sleeve is connected to the valve channel through spokes. The outer circumference of the front end of the valve channel is an annular drain channel 13 and is separated by a cylindrical wall 14. There is a drain port 15 which is closed when the drain sealing piston moves backward to contact the front end surface of the cylinder wall.

In the embodiment of the present invention, a filter screen 16 is arranged in front of the water passage hole of the drainage sealing piston, and a rubber-lined sealing ring 17 is arranged on the rear end surface of the drainage sealing piston to abut against the front end of the water inlet valve flap. Seal its water through hole. The built-in filter is used to filter impurities in the water, and it can be automatically washed without disassembly.

In the embodiment of the present invention, the rear end surface of the water inlet valve flap is provided with a rubber-lined gasket 18, which is used to abut against the front end of the water outlet valve flap to seal its water passage hole.

In the embodiment of the present invention, an O-shaped rubber sealing ring 19 is arranged between the drainage sealing piston and the drainage channel.

In the embodiment of the present invention, the drainage sealing piston is located in the drainer channel inside the valve body, and the water inlet valve flap and the water outlet valve flap are located in the valve channel inside the valve body.

In the embodiment of the present utility model, an O-shaped rubber sealing ring is arranged between the outlet valve flap and the valve channel.

In the embodiment of the present invention, the valve body is composed of a backflow preventer valve body 20 and a drainer valve body 21. The drainer valve body is screwed on the outer periphery of the front end of the backflow preventer valve body, and the water inlet valve disc and the water outlet valve disc are screwed together. The valve channel is located inside the backflow preventer valve body, the drain sealing piston is located in the drainer channel inside the drainer valve body, and the cylindrical wall used to separate the valve channel and the drainer channel is the front end of the backflow preventer valve body.

Specific implementation process:

Normal water supply state as shown in Figure 1: When the pressure of the water inlet is greater than the pressure of the middle cavity, the pressure of the middle cavity is greater than the pressure of the water outlet, the pressure pushes the drainage sealing piston to seal the built-in annular drain, the drainage port is closed, and the inlet valve flap moves backward to the limit position, the limit step is stuck on the guide sleeve, the water outlet valve flap moves backward to the limit position, the double-stage check is in a fully open state, and the water medium flows from the water inlet, to the middle cavity, to the water outlet, and the water is supplied normally.

As shown in Figure 2, the double-stage check seal and the drainer are open to drain: when the pressure of the water inlet decreases, the pressure of the water outlet is greater than the pressure of the water inlet, and the water outlet disc moves towards the water inlet under the action of the main spring, and the water inlet disc At the same time, it pushes the drainage sealing piston in the direction of the water inlet together with the inlet valve disc. The water inlet valve disc is sealed with the drainage sealing piston. Under the joint push of the outlet medium pressure and the main spring force, it provides a sufficient sealing specific pressure, which is consistent with the valve seat. An effective seal is formed to achieve double sealing and prevent water from flowing backwards. At the same time, the drainage sealing piston leaves the annular built-in drainer, and the drain opening is opened to discharge the instantaneously reversed water from the drain outlet and out of the valve.

Easy installation and maintenance, can be installed horizontally or vertically.

The present utility model is not limited to the above-mentioned best embodiment, and anyone can come up with other various forms of backflow preventers with annular built-in drains under the inspiration of the present utility model. All equivalent changes and modifications made according to the scope of the patent application of the present invention shall belong to the scope of the present invention.

Claims (7)

1. The utility model provides a take backflow preventer of built-in drainer of annular which characterized in that: the water-saving valve comprises a valve body, wherein a cylindrical drainage sealing piston, a water inlet valve clack and a water outlet valve clack are sequentially arranged in the valve body from front to back along the direction from a water inlet to a water outlet;

a pre-tightening spring is arranged between the drainage sealing piston and the front inner end face of the valve body, a main spring is arranged between the water outlet valve clack and the rear inner end face of the valve body, and water passing through holes are coaxially arranged in the middle parts of the drainage sealing piston and the water outlet valve clack;

the water inlet valve clack coaxially penetrates through a guide sleeve in the valve body, the front end of the water inlet valve clack is provided with a limiting step, and the outer diameters of the front end and the rear end of the water inlet valve clack are larger than that of the water passing through hole for sliding and sealing the water passing through hole;

the periphery of the guide sleeve is an annular valve channel, the periphery of the front end of the valve channel is an annular drainer channel and is separated by a cylindrical wall, and the periphery of the drainer channel is provided with a water discharge opening for closing when a water discharge sealing piston is moved backwards and abuts against the front end face of the cylindrical wall.

2. A backflow preventer with an annular built-in drainer according to claim 1, wherein: the water passing through hole of the water discharging sealing piston is internally and forwardly provided with a filter screen, and the rear end face of the water discharging sealing piston is provided with a rubber lining sealing ring which is used for abutting against the front end of the water inlet valve clack to seal the water passing through hole.

3. A backflow preventer with an annular built-in drainer according to claim 1, wherein: the back end face of the water inlet valve clack is provided with a rubber lining sealing gasket for abutting against the front end of the water outlet valve clack to seal the water passing through hole of the water outlet valve clack.

4. A backflow preventer with an annular built-in drainer according to claim 1, wherein: an O-shaped rubber sealing ring is arranged between the drainage sealing piston and the drainer channel.

5. A backflow preventer with an annular built-in drainer according to claim 1, wherein: the drainage sealing piston is positioned in a drainer channel inside the valve body, and the water inlet valve clack and the water outlet valve clack are positioned in a valve channel inside the valve body.

6. A backflow preventer with an annular built-in drainer according to claim 5, wherein: an O-shaped rubber sealing ring is arranged between the water outlet valve clack and the valve channel.

7. A backflow preventer with an annular built-in drainer according to claim 1, wherein: the valve body comprises backflow preventer valve body and drainer valve body, and drainer valve body screw thread connects in the front end periphery of backflow preventer valve body soon, and the valve passageway inside the backflow preventer valve body is located with the play water valve clack to water inlet valve clack, and the sealed piston of drainage is located the drainer passageway of drainer valve body for the drum wall of separating valve passageway and drainer passageway is the front end of backflow preventer valve body.

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