阅读说明：本技术 一种反冲洗前置过滤器 (Back-washing pre-filter ) 是由 徐道波 于 2019-09-10 设计创作，主要内容包括：本发明涉及一种反冲洗前置过滤器,包括壳体、进水口、出水口、换向阀和滤网,壳体内部为过滤腔体,滤网设置在壳体内并将所述过滤腔体分隔成内过滤腔体和外过滤腔体,换向阀具有通过旋转可将进水口与内过滤腔体连通的内水道,滤网内沿轴向设置有一冲洗管,冲洗管的管壁分布有若干喷水孔,冲洗管的底部设有只允许水从外部进入管内的单向阀,冲洗管的上端与前置过滤器换向阀的内水道连接。在反冲洗工况时,从冲洗管喷水孔喷出的水具有较高的流速,大幅提高对滤网的反冲洗效果,可以将卡在滤网间隙内的污物颗粒冲出,经反冲洗后滤网的通过性和寿命都得到提高。(The invention relates to a backwashing prefilter, which comprises a shell, a water inlet, a water outlet, a reversing valve and a filter screen, wherein a filter cavity is arranged in the shell, the filter screen is arranged in the shell and divides the filter cavity into an inner filter cavity and an outer filter cavity, the reversing valve is provided with an inner water channel which can communicate the water inlet with the inner filter cavity through rotation, a flushing pipe is arranged in the filter screen along the axial direction, a plurality of water spray holes are distributed on the pipe wall of the flushing pipe, the bottom of the flushing pipe is provided with a one-way valve which only allows water to enter the pipe from the outside, and the upper end of the flushing pipe is connected with the inner water channel of the reversing valve of. Under the back washing working condition, water sprayed from the water spraying holes of the washing pipe has higher flow velocity, the back washing effect on the filter screen is greatly improved, dirt particles clamped in the gap of the filter screen can be washed out, and the passing performance and the service life of the filter screen are improved after the back washing.)

1. The utility model provides a back flush prefilter, includes casing, water inlet, delivery port, switching-over valve and filter screen, and the casing is inside to filter the cavity, and the filter screen setting in the casing and will filter the cavity and separate into interior filter chamber and outer filter chamber, the switching-over valve has through rotatory interior water course that can communicate water inlet and interior filter chamber, its characterized in that: the filter screen is internally provided with a flushing pipe along the axial direction, the pipe wall of the flushing pipe is distributed with a plurality of water spraying holes, the bottom of the flushing pipe is provided with a one-way valve which only allows water to enter the pipe from the outside, and the upper end of the flushing pipe is connected with an inner water channel of a reversing valve of the front filter.

2. The backwash pre-filter as set forth in claim 1, wherein: the flushing pipe and the filter screen are arranged concentrically, the water spraying holes are formed in the surface of the flushing pipe, and the lower insertion depth of the flushing pipe is not lower than 3/4 of the effective height of the filter screen.

3. The backwash pre-filter as set forth in claim 1, wherein: the flushing pipe is eccentrically arranged, and the water spraying holes are arranged on one side, close to the filter screen, of the flushing pipe.

4. The backwash pre-filter as set forth in claim 2 or 3, wherein: the range of the aperture of the water spraying hole of the flushing pipe is as follows: 200-20 microns, and the water spray holes are round, oblong, elliptical, rectangular or triangular.

5. The backwash pre-filter as set forth in claim 1, wherein: the one-way valve is selected from the following components: a ball check valve or a cone check valve.

6. The backwash pre-filter as set forth in claim 1, wherein said inner water passage has an outer water nozzle adapted to be abutted against said water inlet and said water outlet, and an inner water nozzle located at a center of a bottom of the reversing valve, an upper end of the flushing pipe being connected to said inner water nozzle.

7. The backwash pre-filter as set forth in claim 1, wherein: the top of the filter screen or the top of the filter screen bracket is connected or propped against the bottom of the reversing valve.

8. A pre-filter according to claim 1, wherein: the reversing valve is provided with a straight-through water channel which can lead the water inlet and the water outlet to be straight through rotation.

9. The backwash pre-filter as set forth in claim 1, wherein: the reversing valve is also provided with a plug which can plug any one of the water inlet and the water outlet through rotation.

10. The utility model provides a filter screen back flush structure of leading filter which characterized in that: the filter screen is characterized by comprising a flushing pipe arranged in the filter screen along the axial direction, a plurality of water spraying holes are distributed on the pipe wall of the flushing pipe, a one-way valve only allowing water to enter the flushing pipe from the outside is arranged at the bottom of the flushing pipe, and the upper end of the flushing pipe is suitable for being connected with an inner water channel of a reversing valve of a front filter.

Technical Field

The invention relates to a pre-filter, in particular to a filter screen cleaning mechanism of the pre-filter.

Background

The pre-filter is the first coarse filter for domestic water and can filter silt, rust and large particles in tap water. The existing prefilter comprises a filter cylinder and a filter element arranged in the filter cylinder, wherein the upper part of the filter cylinder is provided with a water inlet and a water outlet, and the water inlet is communicated with the water outlet through the filter element. When the water purifier works, water to be filtered enters the filter cartridge from the water inlet, flows through the filter element to obtain purified water, the purified water is discharged from the water outlet, and after long-time use, in order to ensure the water quality, the filter cartridge of the filter needs to be disassembled, and then the filter screen is disassembled to be cleaned, which is very troublesome.

In order to solve the problems of the prior art, people have long searched for and put forward various solutions. For example, chinese patent application CN 103372341a discloses a back-flushing type pre-water filter, which comprises a water inlet and a water outlet, a shell, a filter screen and a water flow direction conversion device; the shell is limited with a filtering cavity, wherein the water flowing in from the water inlet flows out from the water outlet after passing through the filtering cavity; the filter screen sets up in the casing and separates into interior filter chamber body and outer filter chamber body with filtering the cavity.

In addition, as disclosed in chinese utility model patent CN 206746104U, a backwash pre-filter is provided, which switches water channels through a control valve disposed in the device to realize backwash function. The conventional method in the industry is to realize the back washing of the filter screen by reversing the water flow, and the defects of the back washing are that the flow velocity of the water flow is small, the cleaning effect on the filter screen is limited, and the filter screen is often cleaned by combining a scraper device and scraping and washing. Because the restriction of leading filter structure for current scraper blade all sets up in the outside of filter screen, consequently can only scrape the washing to the surface of filter screen, and can't wash the gap of filter screen.

Disclosure of Invention

The technical problem to be solved by the present invention is to overcome the above disadvantages of the prior art and to provide a backwash pre-filter.

In order to solve the technical problems, the invention provides a backwashing prefilter, which comprises a shell, a water inlet, a water outlet, a reversing valve and a filter screen, wherein a filter cavity is arranged in the shell, the filter screen is arranged in the shell and divides the filter cavity into an inner filter cavity and an outer filter cavity, the reversing valve is provided with an inner water channel which can communicate the water inlet with the inner filter cavity through rotation, and the backwashing prefilter is characterized in that: the filter screen is internally provided with a flushing pipe along the axial direction, the pipe wall of the flushing pipe is distributed with a plurality of water spraying holes, the bottom of the flushing pipe is provided with a one-way valve which only allows water to enter the pipe from the outside, and the upper end of the flushing pipe is connected with an inner water channel of a reversing valve of the front filter.

The invention also discloses a filter screen backwashing structure of the pre-filter, which is characterized in that: the filter screen is characterized by comprising a flushing pipe arranged in the filter screen along the axial direction, a plurality of water spraying holes are distributed on the pipe wall of the flushing pipe, a one-way valve only allowing water to enter the flushing pipe from the outside is arranged at the bottom of the flushing pipe, and the upper end of the flushing pipe is suitable for being connected with an inner water channel of a reversing valve of a front filter.

Under the back washing working condition, water sprayed out of the water spraying holes of the washing pipe has higher flow velocity (the principle of reducing current-carrying pressurization), the back washing effect on the filter screen is greatly improved, dirt particles clamped in the gaps of the filter screen can be washed out, the filter screen is improved in trafficability and service life after back washing, and the situation that the traditional low-flow-velocity back washing is difficult to achieve is achieved. Therefore, the invention has the advantages of high backwash flow rate, low water consumption and good cleaning effect. When the filter works, the water primarily filtered by the filter screen jacks up the one-way valve to enter the washing pipe, so that the filtered water can smoothly flow out from the water outlet of the filter through the reversing valve.

In order to realize the straight-through, the reversing valve of the filter provided by the invention is provided with a straight-through water channel which can lead the water inlet and the water outlet to be straight through rotation.

The reversing valve of the invention is provided with two water channels, wherein the filtration and the back flush (the back flush can be realized by rotating 180 degrees) can be realized by the inner water channel, the direct connection can be realized by the direct connection water channel, the filter is shielded, and the water supply is kept uninterrupted. When the filter screen of the backwashing prefilter is seriously blocked or the filter cartridge part of the backwashing prefilter leaks, if a professional maintainer cannot arrive at the site for repair and cannot influence the normal water use life of a user, a simple method is needed for the user to operate, tap water passes through the backwashing prefilter through adjustment, and the professional maintainer waits for the professional maintainer to go to the home for maintenance without influencing the normal water use life of the user.

In addition, the reversing valve can be also provided with a plug which can plug any one of the water inlet and the water outlet through rotation, so that the reversing valve can realize the function of closing water supply.

Drawings

The invention will be further described with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a filtration mode of a first embodiment of a prefilter of this invention.

FIG. 2 is a schematic view of the backwash operation of the first embodiment of the prefilter of the present invention.

FIG. 3 is a schematic view of a straight-through mode of a first embodiment of the prefilter of this invention.

FIG. 4 is a schematic diagram of a filter screen backwash structure according to a first embodiment of the prefilter of the present invention.

FIG. 5 is a schematic diagram of a filter screen backwash structure according to a second embodiment of the prefilter of this invention.

The numbers in the figures are as follows:

1-shell, 3-water inlet, 2-water outlet, 4-filter screen, 5-filter cavity, 6-reversing valve, 7-through water channel 7, 8-adjusting knob, 9-outer water nozzle, 10-inner water nozzle, 11-through water nozzle A, 12-through water nozzle B, 13-flushing pipe; 14-water spray holes, 15-one-way valves, 16-internal water channels and 17-filter screen supports.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention.