CN110613972A - Back-washing pre-filter - Google Patents
Back-washing pre-filter Download PDFInfo
- Publication number
- CN110613972A CN110613972A CN201910851695.7A CN201910851695A CN110613972A CN 110613972 A CN110613972 A CN 110613972A CN 201910851695 A CN201910851695 A CN 201910851695A CN 110613972 A CN110613972 A CN 110613972A
- Authority
- CN
- China
- Prior art keywords
- water
- filter
- flushing pipe
- filter screen
- pipe
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000011045 prefiltration Methods 0.000 title claims abstract description 38
- 238000011001 backwashing Methods 0.000 title abstract description 24
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 126
- 238000011010 flushing procedure Methods 0.000 claims abstract description 47
- 238000005507 spraying Methods 0.000 claims abstract description 17
- 239000007921 spray Substances 0.000 claims abstract description 4
- 238000003780 insertion Methods 0.000 claims description 2
- 230000037431 insertion Effects 0.000 claims description 2
- 238000005406 washing Methods 0.000 abstract description 8
- 230000000694 effects Effects 0.000 abstract description 6
- 239000002245 particle Substances 0.000 abstract description 3
- 238000001914 filtration Methods 0.000 description 15
- 238000004140 cleaning Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 2
- 239000008213 purified water Substances 0.000 description 2
- 239000008399 tap water Substances 0.000 description 2
- 235000020679 tap water Nutrition 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000007790 scraping Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000000844 transformation Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
- B01D29/62—Regenerating the filter material in the filter
- B01D29/66—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps
- B01D29/68—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps with backwash arms, shoes or nozzles
- B01D29/688—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps with backwash arms, shoes or nozzles with backwash arms or shoes acting on the cake side
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D35/00—Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
- B01D35/14—Safety devices specially adapted for filtration; Devices for indicating clogging
- B01D35/147—Bypass or safety valves
Abstract
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.
Description
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.
Example one
As shown in fig. 1 to 4, the backwash pre-filter of this embodiment includes a housing 1, a water inlet 3, a water outlet 2, a filter screen 4, and a washing pipe 13 disposed inside the filter screen, wherein a plurality of water spraying holes 14 are distributed on a pipe wall of the washing pipe 13, and the filter screen is washed by high-pressure water sprayed from the water spraying holes, so as to improve the backwash effect. The interior of the shell 1 is provided with a filtering cavity 5, the filter screen 4 is arranged in the shell 1 and divides the filtering cavity 5 into an inner filtering cavity and an outer filtering cavity, the shell 1 is also internally provided with a reversing valve 6, an adjusting knob 8 for rotating the reversing valve is arranged above the shell 1, and the working conditions of the backwashing prefilter are switched by rotating the adjusting knob 8. The filter generally includes two operating modes of filtration and back flush, and the through operating mode has still been increased to this embodiment. The bottom of the housing 1 may be provided with a waste valve (not shown) for waste disposal.
The reversing valve 6 has an internal water channel 16 (see fig. 4, the internal water channel is shielded by the shell of the reversing valve in fig. 1 to 3) which can communicate the water inlet 3 with the internal filtering cavity by rotation, and a through water channel 7 which can communicate the water inlet 3 and the water outlet 2 by rotation. The inner water channel has an outer nozzle 9 adapted to be abutted with the inlet 3 and the outlet 2, and an inner nozzle 10 at the center of the bottom of the reversing valve 6. The through water channel 7 is provided with a through water nozzle A11 and a through water nozzle B12 which are respectively suitable for being butted with the water inlet 3 and the water outlet 2. The through water channel 7 is positioned at the upper half part of the reversing valve 6, and the ratio of the cross-sectional area of the middle part of the through water channel 7 to the cross-sectional area of the water inlet and the water outlet is about 50%.
In the back-flushing prefilter of this embodiment, the flushing pipe 13 is arranged coaxially with the filter screen 4, and the depth of downward insertion of the flushing pipe is 80% (which should not be less than 75%) of the effective height of the filter screen. The pipe wall of the flushing pipe 13 is distributed with a plurality of water spraying holes 14, and the aperture range of the water spraying holes is as follows: 200 microns to 20 microns, and the water spray holes can be round, oblong, oval, rectangular or triangular. The bottom of the flushing pipe 13 is provided with a one-way valve 15 which only allows water to enter the pipe from the outside, and the upper end of the flushing pipe 13 is connected with an inner water nozzle 10 of the pre-filter reversing valve 6. The sieve 4, and in particular the top of the sieve holder 17, is connected to or against the bottom of the diverter valve 6 such that water flow cannot or hardly pass between the top of the sieve 4 and the bottom of the diverter valve 6, forcing water to pass only through the sieve.
In order to realize the function of blocking the water channel, the reversing valve 6 can be provided with a plug (not shown in the figure) which can block any one of the water inlet and the water outlet by rotating.
As shown in FIG. 1, the filtering condition of the back-flushing prefilter is schematically shown. The water flowing in from the water inlet 3 enters the outer filtering cavity through the gap between the reversing valve 6 and the shell, is filtered by the filter screen 5 to reach the inner filtering cavity, and flows out from the water outlet 2 after the one-way valve 15 is pushed open, passes through the flushing pipe and the inner water channel 16 of the reversing valve 6, so that the preposed filtering of the inlet water is completed.
Under the back washing working condition, the reversing valve 6 only needs to be rotated by 180 degrees, namely, the outer water nozzle 9 is aligned with the water inlet 3. As shown in FIG. 2, the water from the water inlet 3 flows into the flushing pipe 13 through the internal water passage 16 of the reversing valve 6, and the water is forced to be sprayed out from the water spraying holes 14 only due to the blocking of the check valve 15. The aperture of the water spraying holes 14 is small, so that the water pressure is increased, the water flow speed is improved, and the high-flow-speed washing of the filter screen 4 is realized. Water passes through the filter screen 4 and then reaches the outer filter cavity, and then flows out of the water outlet 2, or a drain valve is opened for draining, so that the back washing of the filter screen is completed.
Fig. 3 is a schematic view of the straight-through operation of the backwash pre-filter. Through rotating the reversing valve 6, the through water nozzle A11 and the through water nozzle B12 are respectively butted with the water outlet 2 and the water inlet 3, and at the moment, the water inlet 3 and the water outlet 2 are directly connected through the through water channel 7 of the reversing valve 6.
As shown in fig. 4, the filter screen backwashing structure of the pre-filter of the present embodiment includes a flushing pipe 13 axially disposed in the filter screen 4, a plurality of water spraying holes 14 are distributed on a pipe wall of the flushing pipe 13, a check valve 15 for allowing only water to enter the pipe from the outside is disposed at the bottom of the flushing pipe 13, and the upper end of the flushing pipe 13 is adapted to be connected to (the inner water nozzle 10 of) an inner water channel 16 of the pre-filter reversing valve 6.
Example two
The difference between the backwashing pre-filter of the embodiment and the first embodiment is the structure of backwashing filter screen. As shown in fig. 5, the flushing pipe 13 is arranged eccentrically, and the water spraying holes 14 are arranged on one side of the flushing pipe close to the filter screen, are closer to the filter screen, and have better flushing effect. Other reference numbers refer to fig. 4.
In addition to the above embodiments, the present invention may have other embodiments. All technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the claims of the present invention.
Claims (10)
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.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910851695.7A CN110613972A (en) | 2019-09-10 | 2019-09-10 | Back-washing pre-filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910851695.7A CN110613972A (en) | 2019-09-10 | 2019-09-10 | Back-washing pre-filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110613972A true CN110613972A (en) | 2019-12-27 |
Family
ID=68923085
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910851695.7A Pending CN110613972A (en) | 2019-09-10 | 2019-09-10 | Back-washing pre-filter |
Country Status (1)
| Country | Link |
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| CN (1) | CN110613972A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112546694A (en) * | 2020-11-23 | 2021-03-26 | 余泽飞 | Miniature water filter |
| CN113975875A (en) * | 2021-10-29 | 2022-01-28 | 山东一水环保科技有限公司 | Disassembly-free self-cleaning front-mounted filtering device |
| CN114130087A (en) * | 2021-12-15 | 2022-03-04 | 山西潞安集团余吾煤业有限责任公司 | Back-flushing type pre-filter |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2137557Y (en) * | 1992-08-22 | 1993-07-07 | 王弘仁 | Improved structure of water-filter |
| US20050121382A1 (en) * | 2003-12-05 | 2005-06-09 | Walton Frank A. | Backwash flushing filter |
| CN104906850A (en) * | 2015-05-13 | 2015-09-16 | 深圳奥郎格环保有限公司 | Bidirectional strong spray washing prefilter |
| CN106823535A (en) * | 2017-02-28 | 2017-06-13 | 日丰企业集团有限公司 | Fore filter |
| CN108392879A (en) * | 2018-04-26 | 2018-08-14 | 宁波灏钻科技有限公司 | A kind of multi-functional fore filter and its application method |
| CN108993012A (en) * | 2018-08-13 | 2018-12-14 | 宁波华平智控科技股份有限公司 | A kind of universal backwash fore filter |
| CN210751567U (en) * | 2019-09-10 | 2020-06-16 | 江苏鸿碧科技发展有限公司 | Back-flushing pre-filter and filter screen back-flushing structure thereof |
-
2019
- 2019-09-10 CN CN201910851695.7A patent/CN110613972A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2137557Y (en) * | 1992-08-22 | 1993-07-07 | 王弘仁 | Improved structure of water-filter |
| US20050121382A1 (en) * | 2003-12-05 | 2005-06-09 | Walton Frank A. | Backwash flushing filter |
| CN104906850A (en) * | 2015-05-13 | 2015-09-16 | 深圳奥郎格环保有限公司 | Bidirectional strong spray washing prefilter |
| CN106823535A (en) * | 2017-02-28 | 2017-06-13 | 日丰企业集团有限公司 | Fore filter |
| CN108392879A (en) * | 2018-04-26 | 2018-08-14 | 宁波灏钻科技有限公司 | A kind of multi-functional fore filter and its application method |
| CN108993012A (en) * | 2018-08-13 | 2018-12-14 | 宁波华平智控科技股份有限公司 | A kind of universal backwash fore filter |
| CN210751567U (en) * | 2019-09-10 | 2020-06-16 | 江苏鸿碧科技发展有限公司 | Back-flushing pre-filter and filter screen back-flushing structure thereof |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112546694A (en) * | 2020-11-23 | 2021-03-26 | 余泽飞 | Miniature water filter |
| CN112546694B (en) * | 2020-11-23 | 2022-08-05 | 深圳市优贝尔科技有限公司 | Miniature water filter |
| CN113975875A (en) * | 2021-10-29 | 2022-01-28 | 山东一水环保科技有限公司 | Disassembly-free self-cleaning front-mounted filtering device |
| CN114130087A (en) * | 2021-12-15 | 2022-03-04 | 山西潞安集团余吾煤业有限责任公司 | Back-flushing type pre-filter |
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