CN115671837A

CN115671837A - Laminated composite transverse forward filter with backwashing function

Info

Publication number: CN115671837A
Application number: CN202211411275.5A
Authority: CN
Inventors: 杨德峰; 吴少海; 刘小林
Original assignee: Haining Beishi Environmental Protection Technology Co ltd
Current assignee: Haining Beishi Environmental Protection Technology Co ltd
Priority date: 2022-11-11
Filing date: 2022-11-11
Publication date: 2023-02-03

Abstract

The invention relates to a laminated composite transverse forward filter with a back washing function, which comprises a filter bottle, wherein the filter bottle is provided with a water inlet assembly and a water outlet and sewage discharge assembly; the lamination subunit is provided with a raw water cavity between the lamination subunit and the filter flask, a primary purified water cavity is arranged between the lamination subunit and the filtering function section, a secondary purified water cavity is arranged inside the filtering function section, the raw water cavity and the primary purified water cavity are communicated through the filtering holes of the lamination subunit, the primary purified water cavity is communicated with the secondary purified water cavity through the filtering holes of the filtering function section, and the secondary purified water cavity is communicated with the water outlet port. The structure of the pre-filter is optimized, the pre-filter can perform in-situ backwashing, has a good flushing effect and can be matched with a transverse installation space.

Description

Laminated composite transverse forward filter with backwashing function

Technical Field

The invention relates to a laminated composite transverse forward filter with a backwashing function, and belongs to the technical field of water purification equipment.

Background

Municipal tap water has secondary pollution such as pipeline corrosion, silt and the like to cause the quality of domestic water to be poor, and a pre-filter is usually installed on a household pipeline to improve the quality of the water. The filter element of the pre-filter in the current market mainly adopts a filter screen type structure, and the cleaning method of the filter element comprises positive flushing, back flushing, siphon cleaning or brushing and the like.

The laminated filter consists of a group of discs with grooves on two sides, water flows through the laminated filter, and solid matters in water can be trapped by cross points formed by edges of the grooves. When the filter element lamination needs to be cleaned, the filter element lamination can be conveniently washed and then assembled for recycling.

No matter the single filter screen type structure or the laminated structure, the filter efficiency is low or the risk of failure exists, and how to effectively combine the filter screen type structure and the laminated structure to play a synergistic filtering role is a technical problem to be solved.

In addition, the preposed filter in the prior art is mostly in a T shape, the filter flask is vertically arranged on the machine head, and the filter elements are also vertically arranged in the filter flask. Although the structure has a good filtering effect, the filter bottle and the filter element have certain lengths, so that a large installation space is often occupied in the height direction during installation, the limitation of the installation space is caused, and the limitation in application is large.

The invention aims to provide a transverse-arrangement pre-filter which is optimized in structure, can perform in-situ backwashing and combines a laminated filter structure and a filter screen type filter structure.

Disclosure of Invention

One of the objectives of the present invention is to solve the disadvantages of the pre-filter in the prior art, and to provide a laminated composite type transverse pre-filter with back-washing function. The structure of the front filter is optimized, the back washing can be carried out in situ, the washing effect is good, the front filter can be matched with a transverse installation space, the laminated filter structure and the filter screen type filter structure are combined, and the front filter structure and the filter screen type filter structure are effectively combined and can play a role in collaborative filtering.

The technical scheme adopted by the invention for solving the technical problems is as follows:

transversely put filter forward of lamination combined type with back flush function, including the filter flask, filter flask one end is equipped with into water the subassembly, and the other end is equipped with out water and blowdown subassembly, its characterized in that: the water outlet and sewage discharge assembly is provided with a base matched with the end part of the filter flask, a water outlet port and a sewage discharge port, a base cavity is arranged in the base, a lamination combined type filtering unit is arranged in the filter flask, the lamination combined type filtering unit comprises a filtering and backwashing subunit and a lamination subunit, the filtering and backwashing subunit is inserted in the lamination subunit, and the filtering and backwashing subunit comprises an independent filtering functional section and an independent backwashing functional section; a raw water cavity is arranged between the lamination subunit and the filter flask, a primary purified water cavity is arranged between the lamination subunit and the filtering function section, a secondary purified water cavity is arranged inside the filtering function section, the raw water cavity and the primary purified water cavity are communicated through a filtering hole of the lamination subunit, the primary purified water cavity is communicated with the secondary purified water cavity through a filtering hole of the filtering function section, the secondary purified water cavity is communicated with a water outlet port, and the raw water cavity is communicated with the base cavity and a sewage discharge port; a water inlet channel is arranged between the raw water cavity and the water inlet assembly, a back washing flow channel control cover is arranged in the water inlet assembly, a back washing functional section is provided with a back washing water channel and is positioned in the back washing flow channel control cover, an adjusting assembly is arranged between the filtering and back washing subunit and the base or between the lamination subunits, the filtering and back washing subunit can axially move relative to the lamination subunits through the matching of the adjusting assembly, the filtering and back washing subunit axially moves along the water inlet flow direction, and the water inlet channel can be closed and the back washing water channel can be opened; the filtering and back-flushing subunit moves axially against the water inlet flow direction and can open the water inlet passage and close the back-flushing water passage.

Preferably, the water inlet assembly comprises a water inlet connecting piece and a water inlet end cover, the water inlet connecting piece is fixedly connected with the filter flask in an at least axial direction, the water inlet end cover is coaxially arranged at the inner end of the water inlet connecting piece, the water inlet end cover is provided with a plurality of end cover water passing channels, the end cover water passing channels are communicated with the inner cavity of the water inlet connecting piece, the backwashing flow channel control cover is fixedly arranged at the inner end of the water inlet end cover or integrally formed with the water inlet end cover, the filtering and backwashing subunit moves along the water inlet flow direction in the axial direction relative to the lamination subunit, the end cover water passing channels can be disconnected from the water inlet channel and open the backwashing water channel, the filtering and backwashing subunit moves along the reverse water inlet flow direction in the axial direction relative to the lamination subunit, and the end cover water passing channels can be communicated with the water inlet channel and close the backwashing water channel.

Preferably, the adjusting assembly is arranged between the backwashing subunit and the base, the adjusting assembly comprises an elastic resetting piece, the elastic resetting piece is sleeved on the filtering and backwashing subunit, two ends of the elastic resetting piece are respectively abutted with the inner wall of the base and the end part of the filtering and backwashing subunit, a pressure difference deltaP exists between two sides of the end part of the filtering and backwashing subunit, the deltaP is not less than 0, when the acting force corresponding to the deltaP is greater than the counter-acting force of the elastic resetting piece, the elastic resetting piece is compressed, and the filtering and backwashing subunit axially moves along the water inflow direction; when the acting force corresponding to the delta P is smaller than the reacting force of the elastic resetting piece, the elastic resetting piece resets, and the filtering and backwashing subunit axially moves along the direction opposite to the water flow;

or the adjusting component is arranged between the backwashing subunit and the lamination subunit, the adjusting component comprises an elastic resetting piece, the elastic resetting piece is sleeved on the filtering and backwashing subunit, the filtering and backwashing subunit is provided with a limiting part, two ends of the elastic resetting piece are respectively abutted against the limiting part and the inner wall of the lamination subunit, pressure difference delta P exists between two sides of the end part of the filtering and backwashing subunit, the delta P is not less than 0, when the acting force corresponding to the delta P is greater than the reacting force of the elastic resetting piece, the elastic resetting piece is compressed, and the filtering and backwashing subunit axially moves along the water inlet flow direction; when the acting force corresponding to the delta P is smaller than the reacting force of the elastic resetting piece, the elastic resetting piece resets, and the filtering and backwashing subunit axially moves along the direction opposite to the water flow.

Preferably, the filtering and backwashing subunit comprises a filter screen framework, the filter screen framework comprises a backwashing framework section, a filtering framework section and a water outlet port connecting section, a backwashing filter screen is fixedly arranged on the backwashing framework section, a filter screen is fixedly arranged on the filtering framework section, the lamination subunit comprises a lamination framework and a plurality of laminations fixed outside the lamination framework, a first end cover and a second end cover are respectively arranged at two ends of the lamination framework, a water inlet channel is arranged on the first end cover, the filtering and backwashing subunit is inserted into the lamination subunit, a backwashing opening cover is arranged at one side of the filtering framework positioned at the second end cover, a raw water passing channel is arranged at the second end cover, a backwashing drainage channel is arranged at the backwashing opening cover, a base cavity is communicated with the raw water cavity through the raw water passing channel and the backwashing drainage channel, a sealing part is arranged at a position, close to the outer side of the first end cover, of the elastic backwashing resetting member is sleeved at the water outlet port connecting section, two ends of the elastic resetting member are respectively abutted against the inner wall of the base and the opening end cover, a pressure difference P exists at two sides of the opening end cover, the filtering and the subunit move along the axial direction of the water inlet water flow relative to the lamination, and the water inlet channel is sealed part; the filtering and back-flushing subunit axially moves relative to the lamination subunit against the water inlet flow direction, and the sealing part opens the water inlet channel.

Preferably, the lamination subunit still includes the lamination regulating part, and the lamination skeleton is equipped with the regulating part of adaptation, through the cooperation of regulating part and lamination regulating part, realizes the fixed of lamination and the regulation of filtering the aperture.

Preferably, a lamination framework limiting part is further arranged in the pre-filter, the lamination framework is provided with an adaptive positioning part, the lamination framework is in butt fit with the lamination framework limiting part through the positioning part, the position of the lamination framework in the filter bottle is fixed, and a sealing element or interference fit is arranged between the first end cover and the filter bottle; and two ends of the filtering functional section are connected with the inner wall of the lamination subunit in a sliding and sealing manner.

Preferably, the elastic restoring member is an annular compression spring.

Preferably, the water inlet assembly is further provided with a pressure buffer device for preventing water hammer.

Preferably, the pressure buffering device comprises a cylinder body, an elastic element and a sealing cover, wherein the elastic element and the sealing cover are arranged in the cylinder body; the outer surface of the sealing cover is communicated with the purified water cavity, when the pressure in the pre-filter rises, the elastic element can be compressed, and after the pressure rise is relieved, the elastic element can reset.

Preferably, the blowdown port is provided with a blowdown valve, and the blowdown valve is a manual blowdown valve or an electric blowdown valve or a manual-automatic integral blowdown valve.

The invention has the beneficial effects that: the structure of the preposed filter is optimized, the filter can be used for in-situ backwashing, the flushing effect is good, the filter can be matched with a transverse installation space, the laminated filter structure and the filter screen type filter structure are combined, and the laminated filter structure and the filter screen type filter structure are effectively combined to play a role in collaborative filtering.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the filtration and backwash unit of FIG. 1;

FIG. 3 is an exploded view of FIG. 2;

FIG. 4 is a cross-sectional view of FIG. 1 (filtered state);

fig. 5 is a sectional view (back flush blowdown state) of fig. 1.

In the figure: 1. the filter comprises a filter bottle, 2, a water inlet assembly, 21, a water inlet connecting piece, 22, a water inlet end cover, 22a, an end cover water channel, 3, a water outlet and sewage discharge assembly, 31, a base, 32, a water outlet port, 33, a sewage discharge port, 4, a filtering and backwashing subunit, 41, a filter screen framework, 42, a backwashing filter screen, 43, a filter screen, 44, a backwashing opening end cover, 44a, a backwashing drainage channel, 45, a sealing part, 5, a lamination subunit, 51, a lamination framework, 52, a lamination, 51a, a first end cover, 51b, a second end cover, 51b1, a raw water drainage channel, 6, a backwashing flow channel control cover, 7, an elastic resetting piece, 8, a pressure buffering device, 9, a lamination adjusting piece, 10 and an elastic buffering piece.

Detailed Description

The technical solution of the present invention is further specifically described below by way of specific examples in conjunction with the accompanying drawings.

The embodiment is as follows:

as shown in fig. 1-5, the laminated composite transverse forward filter with a back washing function comprises a filter bottle 1, wherein one end of the filter bottle 1 is provided with a water inlet component 2, the other end of the filter bottle 1 is provided with a water outlet and sewage discharge component 3, the water outlet and sewage discharge component 3 is provided with a base 31, a water outlet port 32 and a sewage discharge port 33 which are matched with the end part of the filter bottle 1, a base cavity is arranged in the base 31, a laminated composite filter unit is arranged in the filter bottle 1, the laminated composite filter unit comprises a filter and back washing subunit 4 and a laminated subunit 5, the filter and back washing subunit 4 is inserted in the laminated subunit 5, and the filter and back washing subunit 4 comprises a filter function section and a back washing function section; a raw water cavity is arranged between the lamination subunit 5 and the filter flask 1, a primary purified water cavity is arranged between the lamination subunit 5 and the filtering function section, a secondary purified water cavity is arranged inside the filtering function section, the raw water cavity and the primary purified water cavity are communicated through a filtering hole of the lamination subunit 5, the primary purified water cavity and the secondary purified water cavity are communicated through a filtering hole of the filtering function section, the secondary purified water cavity is communicated with the water outlet port 32, and the raw water cavity is communicated with the base cavity and the sewage discharge port 33; a water inlet channel is arranged between the raw water cavity and the water inlet assembly 2, a back washing flow channel control cover 6 is arranged in the water inlet assembly 2, a back washing functional section is provided with a back washing water channel and is positioned in the back washing flow channel control cover 6, an adjusting assembly is arranged between the filtering and back washing subunit 4 and the base 31, through the matching of the adjusting assembly, the filtering and back washing subunit 4 can axially move relative to the lamination subunit 5, the filtering and back washing subunit 4 axially moves along the direction of water inlet flow, and the water inlet channel can be closed and the back washing water channel can be opened; the filtering and backwashing subunit 4 moves axially against the direction of the inflow water flow, and can open the water inlet channel and close the backwashing water channel.

Specifically, in this embodiment, the water inlet assembly 2 includes a water inlet connector 21 and a water inlet end cover 22, the water inlet connector 21 is fixedly connected to the filter flask 1 at least in an axial direction (specifically, the water inlet connector 21 may be axially and circumferentially fixed, or may be only axially fixed, and the water inlet connector 21 may rotate in the axial direction, for example, 360 degrees of rotation, and is conventionally selected as required), the water inlet end cover 22 is coaxially disposed at an inner end of the water inlet connector 21, the water inlet end cover 22 is provided with a plurality of end cover water passing channels 22a, the end cover water passing channels 22a are communicated with an inner cavity of the water inlet connector 21, the backwash flow passage control cover 6 is fixedly disposed at an inner end of the water inlet end cover 22 or integrally formed with the water inlet end cover (in this embodiment, preferably, the filtration and backwash flow passage 4 axially moves in a water flow direction relative to the lamination subunit 5, the end cover water passing channels 22a can be disconnected from the water inlet channel and open a backwash water channel, the filtration and backwash subunit 4 axially moves in a direction opposite to the water flow direction relative to the lamination subunit 5, and the end cover water passing channels 22a can be communicated with the backwash water channel and close the backwash water channel.

In this embodiment, the adjusting assembly includes an elastic resetting member 7, the elastic resetting member 7 is sleeved on the filtering and backwashing subunit 4, two ends of the elastic resetting member 7 are respectively abutted against the inner wall of the base 31 and the end of the filtering and backwashing subunit 4, a pressure difference Δ P exists between two sides of the end of the filtering and backwashing subunit 4, the Δ P is not less than 0, when an acting force corresponding to the Δ P is greater than a reaction force of the elastic resetting member 7, the elastic resetting member 7 is compressed, and the filtering and backwashing subunit 4 axially moves along the water flow direction; when the acting force corresponding to the delta P is smaller than the reacting force of the elastic resetting piece 7, the elastic resetting piece 7 is reset, and the filtering and backwashing subunit 4 axially moves along the direction opposite to the water flow.

The structure of the filtering and backwashing subunit is further specifically described below, in this example, the filtering and backwashing subunit 4 includes a filter screen framework 41, the filter screen framework 41 includes a backwashing framework section, a filtering framework section and a water outlet port connecting section, a backwashing filter screen 42 is fixedly arranged on the backwashing framework section, a filter screen 43 is fixedly arranged on the filtering framework section, a lamination subunit 5 includes a lamination framework 51 and a plurality of laminations 52 fixed outside the lamination framework 51, a first end cover 51a and a second end cover 51b are respectively arranged at two ends of the lamination framework 51, a water inlet channel 51a1 is arranged at the first end cover 51a, the filtering and backwashing subunit 4 is inserted inside the lamination subunit 5, a backwashing opening cover 44 is arranged at one side of the second end cover 51b of the filter screen framework 41, a raw water channel 51b1 is arranged at the second end cover 51b, the backwashing opening cover 44 is provided with a backwashing drainage channel 44a, the base cavity is communicated with the raw water cavity through a raw water passing channel 51b1 and the backwashing drainage channel 44a, the backwashing framework section is provided with a sealing part 45 at a position close to the outer side of the first end cover 51a, the elastic resetting piece 7 is sleeved on the water outlet port connecting section, two ends of the elastic resetting piece 7 are respectively abutted with the inner wall of the base and the backwashing opening end cover 44, a pressure difference delta P exists at two sides of the backwashing opening end cover 44, the delta P is not less than 0, the filtering and backwashing subunit 4 axially moves relative to the lamination subunit 5 along the water inlet flow direction, the sealing part 45 can close the water inlet channel, namely the water inlet channel 51a1 is sealed through the sealing part 45, and then the communication between the water inlet channel 51a1 and the end cover water passing channel 22a is blocked; the filtering and backwashing subunit 4 moves axially against the inflow direction of the water relative to the lamination subunit 5, and the sealing part 45 can open the water inlet passage, that is, after the sealing part 45 and the water inlet passage 51a1 are opened, the water inlet passage 51a1 is communicated with the end cover water passage 22 a.

In this embodiment, the structure of the lamination sub-unit 5 is specifically described as follows, the lamination sub-unit 5 further includes a lamination adjuster 9, the lamination frame 51 is provided with an adaptive adjuster, and the fixation of the laminations and the adjustment of the filter aperture are realized through the matching of the adjuster and the lamination adjuster 9. Preferably, an elastic buffer member 10 is further disposed between the lamination adjusting member 9 and the second end cap 51 b.

In this embodiment, a lamination frame limiting part is arranged in the filter bottle 1, a second end cover 51b of the lamination frame 51 is abutted to the lamination frame limiting part, and a sealing element is arranged between the first end cover 51a and the filter bottle 1; and two ends of the filtering functional section are connected with the inner wall of the lamination subunit 5 in a sliding and sealing way.

In this embodiment, the elastic restoring member 7 is an annular compression spring.

Furthermore, in order to prolong the service life of the pre-filter, the water inlet assembly 2 is further provided with a pressure buffer device 8 for preventing water hammer, the pressure buffer device 8 comprises a cylinder body, an elastic element and a sealing cover, the elastic element is arranged in the cylinder body, an elastic element abutting part is arranged in the cylinder body, two ends of the elastic element are respectively abutted against the elastic element abutting part and the inner side of the sealing cover, and the sealing cover is in sliding sealing with the inner wall of the cylinder body; the outer surface of the sealing cover is communicated with the purified water cavity, when the pressure in the pre-filter rises, the elastic element can be compressed, and after the pressure rise is relieved, the elastic element can reset.

In this embodiment, the blowdown port 33 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.

The working principle of the invention is as follows:

in the filtering state, the sewage discharge port 33 is closed, the base cavity is closed, the pressure difference Δ P =0 between the two sides of the end of the filtering and backwashing subunit 4, at this time, the elastic reset member is in the initial state, the positions of the filtering and backwashing subunit 4 and the lamination subunit 5 are in the initial state, and the backwashing channel (backwashing filter net) of the filtering and backwashing subunit 4 is located in the backwashing flow channel control cover 6, as shown in fig. 4, raw water enters from the water inlet assembly 2, flows through the end cover water passage 22a of the water inlet end cover 22, flows through the water inlet channel 51a1, enters the raw water cavity, is filtered by the lamination subunit 5, enters the primary purified water cavity, is filtered by the filtering function section, enters the secondary purified water cavity, and is discharged through the water outlet port 32;

in the backwashing sewage discharge state, the water outlet port 32 is closed, the sewage discharge port 33 is opened, the base cavity is correspondingly opened, the pressure difference between two sides of the end part of the filtering and backwashing subunit 4 is increased to be larger from delta P =0 until the corresponding acting force is larger than the reaction force of the elastic resetting piece, at the moment, the elastic resetting piece 7 is in a compression state, the filtering and backwashing subunit 4 moves relative to the lamination subunit 5 along the water inlet flow direction, the backwashing channel (backwashing filter screen) of the filtering and backwashing subunit 4 extends out of the backwashing flow channel control cover 6 and is opened, as shown in fig. 5, the sealing part 45 seals the water inlet channel, raw water enters from the water inlet assembly 2, flows through the end cover water channel 22a of the water inlet end cover 22, flows through the backwashing filter screen, enters the secondary purified water cavity, flows into the primary purified water cavity after backwashing filtering functional section, then reversely washes the lamination subunit 5, flows into the raw water cavity, then flows through the raw water channel 51b1 and the drainage channel 44a, and finally is discharged through the sewage discharge port 33, so as to realize the backwashing functional section and the lamination subunit 5.

The above-described embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and other variations and modifications may be made without departing from the spirit of the invention as set forth in the claims. If the adjusting component is disposed between the filtering and backwashing subunit and the lamination subunit, specifically, the elastic reset component is sleeved on the filter screen framework 41, the end of the filter screen framework 41 located at the filtering function section is provided with a limiting part, and two ends of the elastic reset component 7 are respectively abutted against the limiting part and the inner wall of the second end cover 51b, and the arrangement mode is similarly described in the invention patent of the front filter component capable of backwashing No. 201610948125.6.

Claims

1. Transversely put filter forward of lamination combined type with back flush function, including the filter flask, filter flask one end is equipped with into water the subassembly, and the other end is equipped with out water and blowdown subassembly, its characterized in that: the water outlet and sewage discharge assembly is provided with a base matched with the end part of the filter flask, a water outlet port and a sewage discharge port, a base cavity is arranged in the base, a lamination combined type filtering unit is arranged in the filter flask, the lamination combined type filtering unit comprises a filtering and backwashing subunit and a lamination subunit, the filtering and backwashing subunit is inserted in the lamination subunit, and the filtering and backwashing subunit comprises a filtering functional section and a backwashing functional section; a raw water cavity is arranged between the lamination subunit and the filter flask, a primary purified water cavity is arranged between the lamination subunit and the filtering function section, a secondary purified water cavity is arranged in the filtering function section, the raw water cavity and the primary purified water cavity are communicated through a filtering hole of the lamination subunit, the primary purified water cavity is communicated with the secondary purified water cavity through a filtering hole of the filtering function section, the secondary purified water cavity is communicated with a water outlet port, and the raw water cavity is communicated with the base cavity and a sewage discharge port; a water inlet channel is arranged between the raw water cavity and the water inlet assembly, a back washing flow channel control cover is arranged in the water inlet assembly, a back washing functional section is provided with a back washing water channel and is positioned in the back washing flow channel control cover, an adjusting assembly is arranged between the filtering and back washing subunit and the base or between the lamination subunits, the filtering and back washing subunit can axially move relative to the lamination subunit through the matching of the adjusting assembly, and the filtering and back washing subunit axially moves along the water inlet flow direction, so that the water inlet channel can be closed and the back washing water channel can be opened; the filtering and back-flushing subunit moves axially against the water inlet flow direction, and can open the water inlet channel and close the back-flushing water channel.

2. The laminated composite transverse pre-filter with backwashing function of claim 1, wherein: the subassembly of intaking includes water inlet connector and water inlet end cover, and water inlet connector and the at least axial fixity of filter flask are connected, and water inlet end cover is coaxial to be located water inlet connector's inner, water inlet end cover is equipped with a plurality of end cover water channel, and end cover water channel communicates with water inlet connector's inner chamber, and fixed the inner of locating water inlet end cover of back flush runner control cover or with water inlet end cover integrated into one piece, filters and back flush subunit along the inflow direction axial displacement of intaking for the lamination subunit, and end cover water channel can break off and open the back flush water passageway with water inlet channel, filters and back flush subunit and for the lamination subunit against the inflow direction axial displacement of intaking, and end cover water channel can communicate with water inlet channel and close the back flush water passageway.

3. The laminated composite transverse forward filter with the back washing function as claimed in claim 1 or 2, wherein the adjusting assembly is arranged between the back washing subunit and the base, the adjusting assembly comprises an elastic resetting member, the elastic resetting member is sleeved on the filtering and back washing subunit, two ends of the elastic resetting member are respectively abutted against the inner wall of the base and the end parts of the filtering and back washing subunit, a pressure difference Δ P exists between two sides of the end parts of the filtering and back washing subunit, the Δ P is not less than 0, when the acting force corresponding to the Δ P is greater than the reacting force of the elastic resetting member, the elastic resetting member is compressed, and the filtering and back washing subunit axially moves along the water inlet flow direction; when the acting force corresponding to the delta P is smaller than the reacting force of the elastic resetting piece, the elastic resetting piece resets, and the filtering and backwashing subunit axially moves along the direction opposite to the water flow;

4. The laminated composite transverse pre-filter with backwashing function as claimed in claim 3, wherein the filtering and backwashing subunit includes a filter screen framework, the filter screen framework includes a backwashing framework section, a filtering framework section and a water outlet port connecting 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 includes a laminated framework and a plurality of laminated sheets fixed outside the laminated framework, two ends of the laminated framework are respectively provided with a first end cover and a second end cover, the water inlet channel is arranged at the first end cover, one side of the filter screen framework located at the second end cover is provided with a backwashing opening cover, the second end cover is provided with a raw water channel, the backwashing opening cover is provided with a backwashing drainage channel, the base cavity is communicated with the raw water cavity through the raw water channel and the backwashing drainage channel, the backwashing framework section is provided with a backwashing portion near the outer side of the first end cover, the elastic reset member is sleeved at the water outlet port connecting section, two ends of the elastic reset member are respectively abutted against the inner wall of the base and the opening end cover, a pressure difference Δ P exists between two sides of the filtering and backwashing subunit moves along the axial direction of the water inlet flow through the sealed water channel; the filtering and back-flushing subunit axially moves relative to the lamination subunit along the direction opposite to the water inlet flow direction, and the sealing part opens the water inlet channel.

5. The laminated composite transverse forward filter with backwashing function according to claim 1 or 2, wherein: the lamination subunit still includes the lamination regulating part, and the lamination skeleton is equipped with the regulating part of adaptation, through the cooperation of regulating part and lamination regulating part, realizes the fixed of lamination and the regulation of filtering the aperture.

6. The laminated composite transverse filter with backwashing function as claimed in claim 1 or 2, wherein: the pre-filter is also internally provided with a laminated framework limiting part, the laminated framework is provided with an adaptive positioning part, the laminated framework is in butt fit with the laminated framework limiting part through the positioning part, the position of the laminated framework in the filter flask is fixed, and a sealing element or interference fit is arranged between the first end cover and the filter flask; and two ends of the filtering functional section are connected with the inner wall of the lamination subunit in a sliding and sealing manner.

7. The laminated composite transverse pre-filter with backwashing function of claim 3, wherein: the elastic reset piece is an annular compression spring.

8. The laminated composite transverse filter with back flushing function as claimed in claim 1 or 2, wherein the water inlet assembly is further provided with a pressure buffer device for preventing water hammer.

9. The laminated composite transverse filter with backwashing function of claim 8, wherein the pressure buffering device comprises a cylinder, an elastic element arranged in the cylinder, and a sealing cover, the cylinder is internally provided with an elastic element abutting portion, two ends of the elastic element are respectively abutted with the elastic element abutting portion and the inner side of the sealing cover, and the sealing cover is in sliding seal with the inner wall of the cylinder; the outer surface of the sealing cover is communicated with the purified water cavity, when the pressure in the pre-filter rises, the elastic element can be compressed, and after the pressure rise is relieved, the elastic element can reset.

10. The laminated composite transverse forward filter with backwashing function according to claim 1 or 2, wherein: the blowdown port is provided with a blowdown valve, and the blowdown valve is a manual blowdown valve or an electric blowdown valve or a manual-automatic blowdown valve.