Laminated composite vertical front-mounted filter with backwashing function

Abstract

The present application relates to a kind of lamination composite vertical front filter with backwashing function, including the head with inlet and outlet, with the filter bottle of head adaptation, filter bottle bottom end is equipped with blowdown piece, head is equipped with the base with filter bottle end adaptation, base is equipped with base cavity in, base cavity is communicated with outlet, filter bottle is equipped with lamination composite filter unit, the lamination composite filter unit includes filter and backwashing subunit and lamination subunit, filter and backwashing subunit are inserted in lamination subunit, filter and backwashing subunit include filter function section and backwashing function section;Lamination subunit is equipped with raw water cavity between filter bottle, lamination subunit and filter function section are equipped with primary purified water cavity, filter function section is equipped with secondary purified water cavity in, raw water cavity and primary purified water cavity are communicated by the filter hole of lamination subunit.The front filter structure is optimized, can backwash in situ, and washing effect is good.

Description

TECHNICAL FIELD

[0001] The present application relates to a laminated composite vertical front filter with backwashing function, belonging to the technical field of water purification equipment. BACKGROUND

[0002] The municipal tap water has poor water quality due to secondary pollution such as pipeline corrosion and silt, so a front filter is usually installed on the household pipeline to improve the water quality. The filter element of the front filter on the market is mainly of a filter screen structure, and the cleaning methods of the filter element include positive flushing, backwashing, siphon cleaning or brushing, etc. The limitation of the filter screen type filter element is that it is difficult to clean the filter element, and the automatic flushing or brushing is even more so, resulting in short service life of the filter screen type filter element and high use cost of the user.

[0003] The laminated filter is composed of a group of disc plates with grooves on both sides. The water flows through the laminated filter, and the intersection points formed by the groove edges can intercept the solids in the water. Due to the simultaneous surface interception and depth coagulation, the filtration effect is greatly improved. When the filter element laminates need to be cleaned, they can be easily flushed clean and then assembled for reuse.

[0004] Whether it is a single filter screen structure or a laminated structure, there is a risk of low filtration efficiency or failure. How to effectively combine the two and play a synergistic filtering role is a technical problem to be solved.

[0005] In addition, the front filter of the prior art is in the shape of "T", the filter bottle is installed in the machine head in a vertical manner, and the filter element is also installed in the filter bottle in a vertical arrangement. As to the backwashing structure, there are series of backwashing implementation ways in the prior art, but the structure implementation way is complex, or the backwashing effect is not good. The present application aims to provide a vertical front filter which is optimized in structure, can backwash in situ, and combines laminated filter structure and filter screen filter structure. SUMMARY

[0006] One of the purposes of the present application is to solve the shortcomings of the "T" shaped front filter of the prior art, and to provide a laminated composite vertical front filter with backwashing function. The structure of the front filter is optimized, can backwash in situ, has good flushing effect, and can match the horizontal installation space.

[0007] The technical scheme adopted by the present application to solve its technical problems is:

[0008] The application discloses a laminated composite vertical front-mounted filter with backwashing function, which comprises a head provided with an inlet and an outlet, a filter bottle matched with the head, a pollution discharge element arranged at the bottom end of the filter bottle, a base matched with the end of the filter bottle, a base cavity arranged in the base, the base cavity being communicated with the outlet, a laminated composite filter unit arranged in the filter bottle, the laminated composite filter unit comprising a filter and backwashing subunit and a laminated subunit, the filter and backwashing subunit being arranged in the laminated subunit, the filter and backwashing subunit comprising a filter function section and a backwashing function section, a raw water cavity being arranged between the laminated subunit and the filter bottle, a first-stage purified water cavity being arranged between the laminated subunit and the filter function section, a second-stage purified water cavity being arranged in the filter function section, the raw water cavity and the first-stage purified water cavity being communicated through filter holes of the laminated subunit, the first-stage purified water cavity and the second-stage purified water cavity being communicated through filter holes of the filter function section, the second-stage purified water cavity being communicated with the outlet, the raw water cavity being communicated with a pollution discharge cavity of the pollution discharge element, the laminated subunit being provided with an inlet channel, the backwashing function section being provided with a backwashing water channel and located in the base cavity, an adjusting assembly being arranged between the filter and backwashing subunit and the bottom of the filter bottle or the laminated subunit, the filter and backwashing subunit being axially moved relative to the laminated subunit through cooperation of the adjusting assembly, the filter and backwashing subunit being axially moved along the direction of the pollution discharge water flow, the inlet channel being closed and the backwashing water channel being opened, the filter and backwashing subunit being axially moved against the direction of the pollution discharge water flow, the inlet channel being opened and the backwashing water channel being closed.

[0009] Preferably, the adjusting assembly is arranged between the filter and backwashing subunit and the bottom of the filter bottle, and comprises an elastic reset element, the elastic reset element being sleeved on the filter and backwashing subunit, the two ends of the elastic reset element being respectively abutted with the bottom of the filter bottle and the end of the filter and backwashing subunit, a pressure difference ΔP existing on both sides of the end of the filter and backwashing subunit, ΔP>=0, when the corresponding force of ΔP is greater than the counterforce of the elastic reset element, the elastic reset element is compressed, and the filter and backwashing subunit is axially moved along the direction of the pollution discharge water flow, and when the corresponding force of ΔP is less than the counterforce of the elastic reset element, the elastic reset element is reset, and the filter and backwashing subunit is axially moved against the direction of the pollution discharge water flow.

[0010] Alternatively, the adjusting assembly is arranged between the filter and backwashing subunit and the laminated subunit, and comprises an elastic reset element, the elastic reset element being sleeved on the filter and backwashing subunit, the filter and backwashing subunit being provided with a limiting portion, the two ends of the elastic reset element being respectively abutted with the limiting portion and the inner wall of the laminated subunit, a pressure difference ΔP existing on both sides of the end of the filter and backwashing subunit, ΔP>=0, when the corresponding force of ΔP is greater than the counterforce of the elastic reset element, the elastic reset element is compressed, and the filter and backwashing subunit is axially moved along the direction of the pollution discharge water flow, and when the corresponding force of ΔP is less than the counterforce of the elastic reset element, the elastic reset element is reset, and the filter and backwashing subunit is axially moved against the direction of the pollution discharge water flow.

[0011] Preferably, the filter and backwashing subunit comprises a filter screen framework, the filter screen framework comprises a backwashing framework section, a filtering framework section and an assembly section, the backwashing framework section is fixedly provided with a backwashing filter screen, the filtering framework section is fixedly provided with a filter screen, the laminated subunit comprises a laminated framework and a plurality of laminated sheets fixed to the outside of the laminated framework, the laminated framework is provided with a first end cover and a second end cover at both ends respectively, a water inlet channel is arranged at the first end cover, the filter screen framework is provided with a backwashing opening cover at one side of the second end cover, a raw water passing channel is arranged between the second end cover and the filter bottle or on the second end cover, the backwashing opening cover is provided with a backwashing drainage channel, a drainage cavity of the drainage member is communicated with a raw water cavity through the raw water passing channel and the backwashing drainage channel, the backwashing framework section is provided with a sealing part at a position close to the outside of the first end cover, the elastic return member is sleeved on the assembly section, both ends of the elastic return member abut against the inner wall of the filter bottle and the backwashing opening cover respectively, there is a pressure difference ΔP on both sides of the backwashing opening cover, the filter and backwashing subunit moves axially relative to the laminated subunit in the direction of sewage flow, and the sealing part can close the water inlet channel; the filter and backwashing subunit moves axially relative to the laminated subunit in the direction opposite to the sewage flow, and the sealing part can open the water inlet channel.

[0012] Preferably, the laminated subunit further comprises a laminated sheet adjusting member, the laminated framework is provided with an adaptive adjusting part, and the fixing of the laminated sheet and the adjustment of the filter aperture are realized through the cooperation of the adjusting part and the laminated sheet adjusting member.

[0013] Preferably, the filter bottle is provided with a laminated framework limiting part, the first end cover of the laminated framework is provided with a positioning part, the first end cover and the filter bottle are axially limited through the abutting cooperation of the positioning part and the laminated framework limiting part, and a sealing element or an interference fit is arranged between the first end cover and the filter bottle; the filter function section is in sliding sealing connection between both ends and the inner wall of the laminated subunit.

[0014] Preferably, an elastic buffer member is further arranged between the laminated sheet adjusting member and the second end cover.

[0015] Preferably, the elastic return member is a ring-shaped compression spring.

[0016] Preferably, the backwashing function section is in sliding sealing connection between both ends and the inner wall of the base cavity.

[0017] Preferably, the backwashing framework section is provided with a sealing element at both ends, and the backwashing framework section and the base cavity are in sliding sealing connection through the cooperation of the sealing element and the inner wall of the base cavity.

[0018] Preferably, the outer port of the drainage member is provided with a drainage valve, and the drainage valve is a manual drainage valve, an electric drainage valve or a manual-automatic integrated drainage valve.

[0019] The beneficial effects of the present application are: the pre-filter structure is optimized, can be backwashed in situ, has good washing effect, and can match the transverse installation space. The laminated composite filter structure of the present application combines the filter screen filter structure and the laminated filter mechanism, protects each other, plays a synergistic filtering role, can provide filtering efficiency, and improves the filtering effect. Specifically, the raw water is first filtered by the laminated filter unit to remove a large amount of rust, silt and other impurities, and then enters the filter screen filter unit for further filtration. That is, pre-filtering through the laminated filter unit and fine filtering through the filter screen can overcome the problem of single laminated filter failure, and can also avoid the accumulation of a large amount of impurities on the surface of the filter screen filter structure, affecting the filtering efficiency and service life. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a structural schematic diagram of the present application;

[0021] Figure 2 is Figure 1 a schematic diagram of the laminated composite filter unit in

[0022] Figure 3 is Figure 2 an exploded view of

[0023] Figure 4 is Figure 1 a sectional view (filtering state) of

[0024] Figure 5 is Figure 1 a sectional view (backwashing and sewage discharge state) of

[0025] In the figure: 1, head, 2, filter bottle, 21, laminated skeleton limiting part, 3, sewage discharge part, 4, filter screen skeleton, 41, backwashing filter screen, 42, filter screen, 43, backwashing opening end cover, 44, sealing part, 5, laminated skeleton, 6, laminated sheet, 51, first end cover, 52, second end cover, 7, elastic reset part, 8, laminated sheet adjusting part, 9, elastic buffer. DETAILED DESCRIPTION

[0026] The technical solutions of the present application will be further specifically described below by means of specific embodiments and in combination with the drawings.

[0027] Embodiment:

[0028] As Figures 1-2As shown, the laminated composite vertical front-mounted filter with backwashing function comprises a head 1 with a water inlet and a water outlet, a filter bottle 2 matched with the head 1, a pollution discharge element 3 arranged at the bottom end of the filter bottle 2, a base matched with the end of the filter bottle 2, a base cavity arranged in the base, the base cavity being communicated with the water outlet, a laminated composite filter unit arranged in the filter bottle 2, the laminated composite filter unit comprising a filter and backwashing subunit and a laminated subunit, the filter and backwashing subunit being inserted into the laminated subunit, the filter and backwashing subunit comprising a filter function section and a backwashing function section; a raw water cavity being arranged between the laminated subunit and the filter bottle 2, a first-stage purified water cavity being arranged between the laminated subunit and the filter function section, a second-stage purified water cavity being arranged inside the filter function section, the raw water cavity and the first-stage purified water cavity being communicated through the filter holes of the laminated subunit, the first-stage purified water cavity and the second-stage purified water cavity being communicated through the filter holes of the filter function section, the second-stage purified water cavity being communicated with the water outlet, and the raw water cavity being communicated with the pollution discharge cavity of the pollution discharge element; the laminated subunit being provided with a water inlet channel, the backwashing function section being provided with a backwashing water channel and located in the base cavity, and an adjusting assembly being arranged between the filter and backwashing subunit and the pollution discharge element, the filter and backwashing subunit being axially movable relative to the laminated subunit through the cooperation of the adjusting assembly, the filter and backwashing subunit being axially moved in the direction of the pollution discharge water flow to close the water inlet channel and open the backwashing water channel, and the filter and backwashing subunit being axially moved against the direction of the pollution discharge water flow to open the water inlet channel and close the backwashing water channel.

[0029] Specifically, in the embodiment, the adjusting assembly comprises an elastic reset element 7, the elastic reset element 7 being sleeved on the filter and backwashing subunit, the two ends of the elastic reset element 7 being respectively abutted against the inner wall of the pollution discharge element and the end of the filter and backwashing subunit, a pressure difference ΔP existing on both sides of the end of the filter and backwashing subunit, ΔP≥0, when the corresponding force of ΔP is greater than the counterforce of the elastic reset element 7, the elastic reset element 7 is compressed, and the filter and backwashing subunit is axially moved in the direction of the pollution discharge water flow; when the corresponding force of ΔP is less than the counterforce of the elastic reset element 7, the elastic reset element 7 is reset, and the filter and backwashing subunit is axially moved against the direction of the pollution discharge water flow.

[0030] The structure of the stacked disc composite filter unit is further described as follows: the filtration and backwashing subunit includes a filter screen frame 4, which includes a backwashing frame section, a filter frame section, and an assembly section. A backwashing filter 41 is fixedly mounted on the backwashing frame section, and a filter screen 42 is fixedly mounted on the filter frame section. The stacked disc subunit includes a stacked disc frame 5 and several stacked discs 6 fixed outside the stacked disc frame 5. A first end cap 51 and a second end cap 52 are respectively provided at both ends of the stacked disc frame 5. A water inlet channel is located on the first end cap 51. A backwash opening cover 43 is provided on one side of the filter screen frame 4 located on the second end cap 52. A raw water passage is provided between the second end cap 52 and the filter bottle 2, or on the second end cap 52. The backwash opening cover 43... A backwash drainage channel is provided. The sewage discharge chamber of the sewage discharge component 3 is connected to the raw water chamber through the raw water passage and the backwash drainage channel. The backwash frame section is provided with a sealing part 44 near the outer side of the first end cover 51. The elastic reset component 7 is sleeved on the assembly section. The two ends of the elastic reset component 7 abut against the inner wall of the sewage discharge component 3 or the inner wall of the filter bottle 2 and the backwash opening end cover 43, respectively. There is a pressure difference ΔP on both sides of the backwash opening end cover 43. ΔP≥0. When the filtration and backwash sub-unit moves axially relative to the stacked plate sub-unit in the direction of sewage flow, the sealing part 44 can close the water inlet channel. When the filtration and backwash sub-unit moves axially relative to the stacked plate unit in the direction of sewage flow, the sealing part 44 can open the water inlet channel.

[0031] In this embodiment, the stacked sheet subunit further includes a stacked sheet adjustment component 8, and the stacked sheet skeleton 5 is provided with a suitable adjustment part. Through the cooperation of the adjustment part and the stacked sheet adjustment component 8, the stacked sheet 6 can be fixed and the filter pore size can be adjusted.

[0032] Furthermore, the filter bottle 2 is provided with a stacked frame limiting part, and the first end cap 51 of the stacked frame 5 is provided with a positioning part, which abuts against the stacked frame limiting part (e.g., Figure 4 , 5 As shown, a concave-convex abutment fit is adopted to achieve abutment limit and axial limit. A sealing element or interference fit is provided between the first end cap 51 and the filter bottle 2. The two ends of the filter functional section are slidably sealed to the inner wall of the stacked disc sub-unit.

[0033] In this embodiment, an elastic buffer 9 is also provided between the stacked plate adjusting member 8 and the second end cover 52. In this embodiment, the elastic reset member 7 is a ring compression spring.

[0034] To ensure effective filtration and backwashing, the backwashing functional section is slidably sealed to the inner wall of the base cavity at both ends. Specifically, the backwashing frame section is equipped with sealing elements at both ends, and the backwashing frame section is slidably sealed to the base cavity through the cooperation of the sealing elements with the inner wall of the base cavity.

[0035] In the embodiment, the outer port of the blowdown member 3 is provided with a blowdown valve 31, which is a manual blowdown valve, an electric blowdown valve or a manual-electric blowdown valve.

[0036] The working principle of the present application is as follows:

[0037] In the filtering state, the blowdown valve 31 is closed, the blowdown cavity is closed, the pressure difference ΔP of the two sides of the end of the filtering and backwashing subunit is 0, at this time, the elastic reset member 7 is in the initial state, the positions of the filtering and backwashing subunit and the laminated subunit are in the initial state, and the backwashing channel (backwashing filter screen) of the filtering and backwashing subunit is located in the base cavity, as shown in Figure 4 The raw water enters the water inlet of the head 1, enters the raw water cavity through the water inlet channel of the first end cover 51, and then enters the primary purified water cavity after being filtered by the laminated subunit, and then enters the secondary purified water cavity after being filtered by the filtering function section, and then is discharged through the water outlet of the head 1.

[0038] In the backwashing and blowdown state, the blowdown valve 31 is opened, the corresponding blowdown cavity is opened, the pressure difference of the two sides of the end of the filtering and backwashing subunit is increased from ΔP=0 to a larger value, until the corresponding force is greater than the counterforce of the elastic reset member 7, at this time, the elastic reset member 7 is in the compressed state, the filtering and backwashing subunit moves relative to the laminated subunit in the direction of the blowdown water flow, and the backwashing channel (backwashing filter screen) of the filtering and backwashing subunit is stretched out of the base cavity and opened, as shown in Figure 5 The sealing part 44 closes the water inlet channel, the raw water enters the water inlet of the head 1, flows through the backwashing filter screen, enters the secondary purified water cavity, and then enters the primary purified water cavity after backwashing the filtering function section, and then flows to the raw water cavity after backwashing the laminated subunit, and then enters the blowdown cavity through the raw water water inlet channel and the backwashing water outlet channel, and finally is discharged through the blowdown valve 31, so as to realize backwashing of the filtering function section and the laminated subunit.

[0039] The present application has the following advantages: the structure of the pre-filter is optimized, can be backwashed in situ, has good washing effect, and can match the horizontal installation space. The laminated composite filter structure of the present application combines the filter screen filter structure and the laminated filter structure, protects each other, and plays a synergistic filtering role, can provide filtering efficiency, and improves the filtering effect. Specifically, the raw water is first filtered by the laminated filter unit to remove a large amount of rust, sand and other impurities, and then enters the filter screen filter unit for further filtering. That is, the raw water is pre-filtered by the laminated filter unit and then precisely filtered by the filter screen, which can overcome the problem of single laminated filter failure and avoid the accumulation of a large amount of impurities on the surface of the filter screen filter structure, affecting the filtering efficiency and service life.

[0040] The above-described embodiments are only a preferred scheme of the present application, and do not limit the present application in any form, and other variants and modifications are possible without departing from the technical scheme recited in the claims. For example, the adjusting assembly is arranged between the filter and backwashing subunit and the laminated subunit, specifically, the elastic reset member is sleeved on the filter screen framework 4, the filter screen framework 4 is provided with a limiting portion at the end of the filtering function section, and the two ends of the elastic reset member 7 are respectively in abutment with the limiting portion and the inner wall of the second end cover 52. This arrangement is similar to the description in the No. 201610948125.6 Invention Patent for Backwashable Pre-filter Assembly.

Claims

1. A stacked disc composite vertical forward filter with backwashing function, comprising a head with an inlet and an outlet, a filter bottle adapted to the head, and a drain device at the bottom of the filter bottle, characterized in that: The head is provided with a base matched with the end of the filter bottle, the base is provided with a base cavity, the base cavity is communicated with the water outlet, the filter bottle is provided with a laminated composite filter unit, the laminated composite filter unit comprises a filter and backwashing subunit and a laminated subunit, the filter and backwashing subunit is inserted into the laminated subunit, the filter and backwashing subunit comprises a filter function section and a backwashing function section; a raw water cavity is arranged between the laminated subunit and the filter bottle, a first purified water cavity is arranged between the laminated subunit and the filter function section, a second purified water cavity is arranged inside the filter function section, the raw water cavity and the first purified water cavity are communicated through the filter hole of the laminated subunit, the first purified water cavity and the second purified water cavity are communicated through the filter hole of the filter function section, the second purified water cavity is communicated with the water outlet, and the raw water cavity is communicated with the blowdown cavity of the blowdown piece; the laminated subunit is provided with a water inlet channel, the backwashing function section is provided with a backwashing water channel and located in the base cavity, an adjusting assembly is arranged between the filter and backwashing subunit and the bottom of the filter bottle or the laminated subunit, through cooperation of the adjusting assembly, the filter and backwashing subunit can move axially relative to the laminated subunit, the filter and backwashing subunit moves axially along the direction of blowdown water flow, can close the water inlet channel and open the backwashing water channel; the filter and backwashing subunit moves axially against the direction of blowdown water flow, can open the water inlet channel and close the backwashing water channel.

2. The lamination composite type vertical pre-filter having a backwash function according to claim 1, wherein, The adjusting assembly is arranged between the filter and backwashing subunit and the bottom of the filter bottle, comprises an elastic reset piece, the elastic reset piece is sleeved on the filter and backwashing subunit, two ends of the elastic reset piece are respectively abutted with the bottom of the filter bottle and the end of the filter and backwashing subunit, there is a pressure difference △P between the two sides of the end of the filter and backwashing subunit, △P≥0, when the corresponding force of △P is greater than the counterforce of the elastic reset piece, the elastic reset piece is compressed, and the filter and backwashing subunit moves axially along the direction of blowdown water flow; when the corresponding force of △P is less than the counterforce of the elastic reset piece, the elastic reset piece resets, and the filter and backwashing subunit moves axially against the direction of blowdown water flow; Alternatively, the adjusting assembly is arranged between the filter and backwashing subunit and the laminated subunit, comprises an elastic reset piece, the elastic reset piece is sleeved on the filter and backwashing subunit, the filter and backwashing subunit is provided with a limiting part, two ends of the elastic reset piece are respectively abutted with the limiting part and the inner wall of the laminated subunit, there is a pressure difference △P between the two sides of the end of the filter and backwashing subunit, △P≥0, when the corresponding force of △P is greater than the counterforce of the elastic reset piece, the elastic reset piece is compressed, and the filter and backwashing subunit moves axially along the direction of blowdown water flow; when the corresponding force of △P is less than the counterforce of the elastic reset piece, the elastic reset piece resets, and the filter and backwashing subunit moves axially against the direction of blowdown water flow.

3. The lamination composite type vertical pre-filter having a backwash function according to claim 2, wherein, The filter and backwashing subunit comprises a filter screen framework, the filter screen framework comprises a backwashing framework section, a filtering framework section and an assembly section, the backwashing framework section is fixedly provided with a backwashing filter screen, the filtering framework section is fixedly provided with a filter screen, the laminated sheet subunit comprises a laminated sheet framework and a plurality of laminated sheets fixed to the outside of the laminated sheet framework, the laminated sheet framework is provided with a first end cover and a second end cover at two ends respectively, a water inlet channel is arranged at the first end cover, the filter screen framework is provided with a backwashing opening cover on one side of the second end cover, a raw water passing channel is arranged between the second end cover and the filter bottle or on the second end cover, the backwashing opening cover is provided with a backwashing drainage channel, a blowdown cavity of the blowdown piece is communicated with a raw water cavity through the raw water passing channel and the backwashing drainage channel, the backwashing framework section is provided with a sealing part at a position close to the outside of the first end cover, the elastic return piece is sleeved on the assembly section, two ends of the elastic return piece are respectively abutted against the inner wall of the filter bottle and the backwashing opening end cover, there is a pressure difference ΔP on two sides of the backwashing opening end cover, the filter and backwashing subunit moves axially relative to the laminated sheet subunit in the direction of sewage flow, and the sealing part can close the water inlet channel; the filter and backwashing subunit moves axially relative to the laminated sheet subunit in the direction opposite to the sewage flow, and the sealing part can open the water inlet channel.

4. The lamination composite type vertical pre-filter having a backwash function according to claim 3, wherein: The laminated sheet subunit further comprises a laminated sheet adjusting piece, the laminated sheet framework is provided with an adaptive adjusting part, and the fixing of the laminated sheet and the adjustment of the filter aperture are realized through the cooperation of the adjusting part and the laminated sheet adjusting piece.

5. The lamination composite type vertical pre-filter having a backwash function according to claim 3 or 4, characterized in that: The filter bottle is provided with a laminated sheet framework limiting part, the first end cover of the laminated sheet framework is provided with a positioning part, the first end cover and the filter bottle are provided with a sealing element or an interference fit through the abutment and cooperation of the positioning part and the laminated sheet framework limiting part for axial limiting, and the sliding sealing connection between the two ends of the filter function section and the inner wall of the laminated sheet subunit is realized.

6. The lamination composite type vertical pre-filter having a backwash function according to claim 3 or 4, characterized in that: An elastic buffer piece is further arranged between the laminated sheet adjusting piece and the second end cover.

7. The lamination composite type vertical pre-filter having a backwash function according to claim 2 or 3, characterized in that: The elastic return piece is a ring-shaped compression spring.

8. The lamination composite type vertical pre-filter having a backwash function according to claim 1 or 2, wherein The backwashing function section is in sliding sealing connection between the two ends and the inner wall of the base cavity.

9. The lamination composite type vertical pre-filter having a backwash function according to claim 3 or 4, wherein The backwashing framework section is provided with a sealing element at two ends, and the backwashing framework section and the base cavity are in sliding sealing connection through the cooperation of the sealing element and the inner wall of the base cavity.

10. The lamination composite type vertical pre-filter having a backwash function according to claim 1 or 2, wherein: The outer port of the blowdown piece is provided with a blowdown valve, and the blowdown valve is a manual blowdown valve, an electric blowdown valve or a manual-automatic blowdown valve.

Images