CN205978657U - Low -resistance decompression type backflow prevention device - Google Patents

Abstract

The utility model discloses a low-resistance decompression type backflow preventer, which comprises a valve body, the inlet and outlet of the valve body are provided with a check mechanism for preventing fluid backflow, and the check mechanism includes a valve fixedly connected with the valve body Seat, a movable rod is set on the central axis of the valve seat, and a connecting sleeve that slides with the movable rod is arranged in the middle of the valve seat. The valve clack is provided with a compression spring between the inlet end of the movable rod and the connecting sleeve, and a permanent magnet is provided in the valve seat, and the permanent magnet can generate a magnetic attraction force on the valve clack. The purpose of the utility model is to provide a low-resistance decompression type backflow preventer, which can greatly reduce the water loss of the valve while ensuring a large valve closing pressure difference, and play a role of high efficiency and energy saving.

Description

A low-resistance decompression type backflow preventer

technical field

The utility model relates to the field of fluid control, in particular to a low-resistance decompression type backflow preventer.

Background technique

The low-resistance decompression type backflow preventer is mainly used in various tap water and direct drinking water systems to prevent secondary pollution caused by medium backflow. According to the provisions of the national standard GB/T25178-2010 "Decompression Type Backflow Preventer", the decompression type backflow preventer is the highest safety level equipment for preventing medium backflow, which is divided into two-stage independent check and low pressure differential drainage in the middle cavity , there are very strict requirements on the valve closing pressure difference and the water discharge pressure difference, but combined with China's national conditions, there are also requirements on the valve water loss. This requirement is different from the source of the standard (the United States), and the higher valve closing pressure difference These two requirements and lower water loss are in conflict with each other in the current spring check valve technology.

Utility model content

The purpose of the utility model is to provide a low-resistance decompression type backflow preventer, which can greatly reduce the water loss of the valve while ensuring a large valve closing pressure difference, and play a role of high efficiency and energy saving.

In order to achieve the above object, the technical solution adopted by the utility model is:

A low-resistance decompression type backflow preventer, including a valve body, characterized in that: the inlet and outlet of the valve body are provided with a check mechanism for preventing fluid backflow, and the check mechanism includes a valve seat fixedly connected to the valve body , a movable rod is set on the central axis of the valve seat, and a connecting sleeve that slides with the movable rod is arranged in the middle of the valve seat. For the valve disc, a compression spring is provided between the end of the movable rod near the inlet and the connecting sleeve, and a permanent magnet is provided in the valve seat, and the permanent magnet can generate magnetic attraction to the valve disc.

The utility model is further provided that a central shaft is vertically arranged in the middle of the valve body, a valve cover and a diaphragm assembly are arranged on the upper end of the central shaft, the diaphragm assembly and the valve cover form a closed space, and the central shaft The lower end is connected with a liquid discharge valve disc, the valve body is provided with a liquid discharge port corresponding to the liquid discharge valve disc, and the lower side of the liquid discharge port is connected with a water leakage funnel.

The utility model is further configured as follows: the valve wall at the inlet of the valve body is provided with a first through hole, the valve wall at the outlet of the valve body is provided with a second through hole, and the valve cover is provided with a third through hole and In the fourth through hole, the first through hole and the third through hole are connected through a water pipe, and the water pipe is provided with a first switch valve, and the second through hole and the fourth through hole are respectively connected with the second switch valve and the third switch valve.

The utility model is further configured that the valve seat is fixedly connected with the valve body through a collar.

The core technology of the low-resistance decompression type backflow preventer provided by the utility model lies in: through the non-return mechanism combined with a permanent magnet and a flexible spring, the magnetic force of the magnet is used to realize the valve closing force when the valve is closed. The large and flexible spring only serves to push the disc to close, so when the valve is opened, the spring force has little resistance to the hydraulic force, and the main source of the pressure difference between the front and rear of the valve is the water resistance of the flow channel in the valve, so its water The water loss is only equivalent to the water loss of the conventional spring check valve. This structure ensures a large valve closing pressure difference and greatly reduces the valve water loss, which plays a role of high efficiency and energy saving.

In addition, in order to ensure the sensitivity of the water discharge, a large-diaphragm diaphragm assembly is used to amplify the valve closing force generated by the pressure difference, which can reliably close the water discharge valve disc while responding to the water discharge within a small pressure difference range.

Secondly, the check mechanism of the valve is installed in one piece, and only need to take out the collar during maintenance, and then the check valve can be taken out of the valve body from the middle of the valve for maintenance, which is very convenient.

The non-return mechanism combined with permanent magnet and flexible spring solves the problem of large water resistance of the decompression backflow preventer. At the same time, the integrated non-return assembly improves the reliability of the valve and facilitates maintenance.

Description of drawings

Fig. 1 is the structural representation of the utility model.

detailed description

Below in conjunction with accompanying drawing and embodiment, the specific embodiment of the utility model is described in further detail. The following examples are used to illustrate the utility model, but not to limit the scope of the utility model.

The utility model is described below with reference to Fig. 1.

A low-resistance decompression type backflow preventer, including a valve body 1. The left and right ends of the valve body are respectively an inlet and an outlet. The body is fixedly connected to the valve seat 2, and a movable rod 3 is arranged on the central axis of the valve seat 2. In the middle of the valve seat 2, there is a connecting sleeve 4 that is slidingly matched with the movable rod 3. The outer wall of the connecting sleeve 4 is connected to the valve seat through the rib plate 5 2, the movable rod 3 is connected to the valve disc 6 which is sealingly matched with the valve seat 2 at the end far away from the inlet, and the movable rod 3 is provided with a compression spring 7 between the inlet end and the connecting sleeve 4, and the valve seat 2 A permanent magnet 8 is provided, and the permanent magnet 8 can generate magnetic attraction to the valve disc 6 .

Through the non-return mechanism combined with permanent magnets and flexible springs, the magnetic characteristics of the magnets are used to achieve a larger closing force when the valve is closed, and the flexible spring only serves to push the valve disc to close, so when the valve is opened At this time, the resistance of the spring force to the hydraulic force is very small, and the main source of the pressure difference between the front and rear of the valve is the water resistance of the flow channel in the valve, so its water loss is only equivalent to the water loss of a conventional spring check valve. At the same time, the valve pressure difference is greatly reduced, which plays a role in high efficiency and energy saving.

In the middle of the valve body 1, a central shaft 9 is vertically arranged, and the upper end of the central shaft 9 is provided with a valve cover 10 and a diaphragm assembly 11. The diaphragm assembly 11 and the valve cover 10 form a closed space, and the lower end of the central shaft 9 is connected to The valve body 1 is provided with a liquid discharge port 13 corresponding to the liquid discharge valve disc 12 , and the lower side of the liquid discharge port 13 is connected with a water leakage funnel 14 . By opening the drain valve disc 12, the liquid is discharged through the drain funnel 14. In order to ensure the sensitivity of the water discharge, a large-diaphragm-type diaphragm assembly is used to amplify the closing force generated by the pressure difference, which can respond to the water discharge within a small pressure difference range and at the same time reliably close the water discharge valve.

The valve wall at the inlet of the valve body 1 is provided with a first through hole 15, the valve wall at the outlet of the valve body 1 is provided with a second through hole 16, and the valve cover is provided with a third through hole 17 and a fourth through hole 18. , the first through hole 15 and the third through hole 17 are connected by a water pipe, and the water pipe is provided with a first switch valve 19, and the second through hole 16 and the fourth through hole 18 are respectively connected with the second switch valve 20 and the third switch valve 21.

The valve seat 2 is fixedly connected with the valve body 1 through a collar 22 . The check mechanism of the valve is installed in one piece. During maintenance, only the collar needs to be taken out, and the check valve can be taken out of the valve body from the middle of the valve for maintenance, which is very convenient.

The above is only the preferred embodiment of the utility model, it should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the utility model, some improvements and modifications can also be made. These improvements and modifications should also be regarded as the protection scope of the present utility model.

Claims (4)

1. A low-resistance decompression type backflow preventer, comprising a valve body, characterized in that: the inlet and outlet of the valve body are provided with a check mechanism to prevent fluid backflow, and the check mechanism includes a fixed connection with the valve body Valve seat, a movable rod is set on the central axis of the valve seat, and a connecting sleeve that slides with the movable rod is arranged in the middle of the valve seat. For the matched valve clack, a compression spring is provided between the inlet end of the movable rod and the connecting sleeve, and a permanent magnet is provided in the valve seat, which can generate magnetic attraction force to the valve clack. 2. A low-resistance decompression type backflow preventer according to claim 1, characterized in that: a central shaft is vertically arranged in the middle of the valve body, and a valve cover and a diaphragm assembly are arranged at the upper end of the central shaft , the diaphragm assembly and the valve cover form a closed space, the lower end of the central shaft is connected to the discharge valve disc, the valve body is provided with a discharge port corresponding to the discharge valve disc, and the lower side of the discharge port is connected to a leaking bucket. 3. A low-resistance decompression type backflow preventer according to claim 1 or 2, characterized in that: the valve wall at the inlet of the valve body is provided with a first through hole, and the valve wall at the outlet of the valve body A second through hole is provided on the valve cover, a third through hole and a fourth through hole are provided on the valve cover, the first through hole and the third through hole are connected by a water pipe, and the first switch valve is provided on the water pipe, and the second through hole The second on-off valve and the third on-off valve are respectively connected to the fourth through hole. 4. A low-resistance decompression type backflow preventer according to claim 3, wherein the valve seat is fixedly connected to the valve body through a collar.