CN212631934U

CN212631934U - Front filter

Info

Publication number: CN212631934U
Application number: CN202020528392.XU
Authority: CN
Inventors: 苏杰; 林细勇; 秦燕芝; 蒋玉林; 赖化明; 谢承志
Original assignee: Rifeng Enterprise Foshan Co Ltd; Rifeng Enterprise Group Co Ltd; Rifeng Technology Co Ltd
Current assignee: Rifeng Enterprise Foshan Co Ltd; Rifeng Enterprise Group Co Ltd; Rifeng Technology Co Ltd
Priority date: 2020-04-10
Filing date: 2020-04-10
Publication date: 2021-03-02
Anticipated expiration: 2030-04-10

Abstract

The utility model relates to a pipeline water purification unit technical field discloses a leading filter, a serial communication port, include: the backwashing knob component, the conduction component, the filtering component, the scraping knob component and the sewage discharge component change the flow direction from the original flow-cup body-filtering screen outer wall-filtering screen inner hole-valve core-flow direction terminal pipeline flow direction to the flow-valve core-filtering screen inner hole-filtering screen outer wall-cup body-sewage discharge outlet flow direction by rotating the backwashing knob, and impurities in the original filtering screen small holes are flushed out along with the flow of water to the filtering screen outer wall under the action of water flow pressure.

Description

Front filter

Technical Field

The utility model relates to a pipeline water purification unit technical field discloses a leading filter.

Background

At present, the front filter can intercept and filter sand, rust and other particles and is used for filtering and purifying water quality. Through investigation, the following problems are found to exist in part of the prefilter: part of the pre-filters only have a filtering function, and when the filters are cleaned, the filters need to be detached and cleaned after pipelines are cut off, so that the operation is complex, and the trouble and the labor are wasted. The filter also has a pre-filter with a scraping technology, which has certain scraping capacity, but impurities can not be thoroughly scraped and washed because of permeating into filter element holes of a filter screen, so that dirt is easily accumulated, and the filter holes are easily blocked after a long time, so that the flow of a tail end pipeline is reduced, and the normal domestic water of a user is influenced; if the impurities in the filter screen need to be cleaned, the pipeline needs to be cut off, the filter screen filter element needs to be detached, and the impurities in the filter screen holes need to be brushed away by a brush, so that the operation is complex, and the trouble and the labor are wasted.

SUMMERY OF THE UTILITY MODEL

The utility model provides a leading filter, the purpose is to the inconvenient abluent problem of above-mentioned filter, provides an easy operation, and the practicality is strong, and the outward appearance is pleasing to the eye, need not to cut off the pipeline and just can reach effective washing, the good leading filter of cleaning performance.

In order to solve the technical problem, the utility model provides a leading filter, it includes: back flush knob subassembly, switch-on subassembly, filtering component, scrape and wash knob subassembly and blowdown subassembly, back flush knob subassembly includes: back flush knob, valve rod and case, the case includes: first runner, second runner and valve rod mounting groove, first discharge orifice and second discharge orifice are seted up at first runner both ends, third discharge orifice and fourth discharge orifice are seted up at second runner both ends, the one end of back flush knob connection valve rod, the other end of valve rod is connected on the valve rod mounting groove, the subassembly that switches on includes the tee bend valve body, set up first pipeline, second pipeline, third pipeline and valve rod mounting hole on the tee bend valve body, the case sets up the inside cavity of tee bend valve body, the valve rod is worn to locate the valve rod hole, filtering component includes: filter screen skeleton, filter screen, scrape and wash strip and cup, filter screen skeleton one end rotatable connect in the third flow hole, the third runner is seted up in inside to filter screen skeleton fretwork, third flow passage one end with the third flow hole sets up correspondingly, the filter screen cladding is in the periphery of filter screen skeleton, the cup inner wall sets up a plurality ofly scrape and wash the strip, the cup cover is established the periphery of filter screen, cup one end with third pipe connection, the connecting piece mounting hole has been seted up to the cup other end, the periphery of filter screen with scrape and wash the contact of strip, scrape and wash the knob subassembly and include: scrape and wash knob and connecting piece, scrape and wash the inside cavity of knob, scrape and wash the knob lateral wall and set up the valve mounting hole, connecting piece one end with filter screen skeleton one end is connected, the inside fourth runner that sets up of connecting piece, the fourth runner with the third runner corresponds the setting, the connecting piece is worn to establish inside the connecting piece mounting hole, the blowdown subassembly includes: blowoff valve and blowoff valve knob, the blowoff valve sets up scrape and wash the inside cavity of knob, the blowoff valve includes: valve pipe and valve, valve pipe one end is connected the connecting piece other end, the valve with the valve mounting hole corresponds the setting, the blowoff valve knob wears to establish the valve mounting hole with the valve is connected.

According to the preferable scheme, the backwashing knob component is in a ball valve ball shape, a screw hole is formed in the center of the backwashing knob, a screw penetrates through the screw hole, a decoration cover is installed on the screw, the screw penetrates through the backwashing component and is connected to the valve rod, and the valve rod is sleeved with the leveling clamp spring.

Preferably, a first sealing ring is arranged at the joint of the valve rod mounting hole and the valve rod.

Preferably, the conduction assembly further comprises a shell, and the shell covers the outer surface of the three-way valve body.

As a preferred scheme, set up first screw thread, second screw thread and third screw thread on first pipeline, second pipeline and the third pipeline respectively, wherein, first screw thread and second screw thread are the external screw thread, the pipeline mouth of first pipeline and second pipeline all sets gradually sealed the pad, the metal packing ring, the second sealing washer, just set up the screw thread protective sheath on first screw thread and the second screw thread.

Preferably, a third seal ring is arranged on the third flow hole, a fourth seal ring is arranged at one end of the third flow channel, which is connected with the third flow hole, and the third seal ring is in seamless contact with the fourth seal ring.

As a preferred scheme, a fourth thread is arranged at one end of the cup body and is an external thread, the fourth thread is in screwed connection with the third thread, and a fifth sealing ring is arranged at the joint of the cup body and the three-way valve body.

As a preferred scheme, a sixth sealing ring is arranged at the joint of the filter screen framework and the valve core.

As a preferred scheme, a seventh sealing ring and an opening clamping ring are sequentially arranged at the joint of the filter screen framework and the connecting piece.

Preferably, one end of the fourth flow passage is provided with a fifth thread, one end of the valve pipe is provided with a sixth thread, the fifth thread is an internal thread, the sixth thread is an external thread, and the fifth thread is screwed with the sixth thread.

As the preferred scheme, scrape and wash knob subassembly still including scraping and washing knob upper cover, base and quick plug, it establishes to scrape to wash the knob upper cover for the ring disk form and seamless the cover cup outside surface, scrape wash the knob upper cover outer along with scrape and wash knob one end and link to each other, it is connected with to scrape the knob other end the base, the centre bore is seted up at the base center, valve rod one end is passed the centre bore and is connected quick plug.

Preferably, a buckle is arranged at the joint of the blowoff valve knob and the valve.

As a preferred scheme, a baffle is arranged at a gap between the cup body and the filter screen, and the outer diameter of the baffle is larger than that of the upper end of the filter screen.

Preferably, a protrusion is arranged at one end of the filter screen framework, a flow passage is formed in the protrusion, the protrusion is connected to the third flow passage, holes are formed in two sides of the protrusion, and the protrusion is inserted into the fourth flow passage.

The utility model relates to a steel construction technical field discloses a leading filter, a serial communication port, include: the back washing knob component, the conduction component, the filtering component, the scraping and washing knob component and the sewage discharging component change the flow direction of water flow from the original flow-cup body-filter screen outer wall-filter screen inner hole-valve core-flow direction end pipeline flow direction to the flow-valve core-filter screen inner hole-filter screen outer wall-cup body-sewage discharging port flow direction by rotating the back washing knob, under the action of water flow pressure, impurities in the small holes of the original filter screen are flushed out along with the water flow towards the outer wall of the filter screen, and meanwhile, the scraping and washing knob is rotated to drive the filter screen framework and the filter screen, the scraping and washing strip on the cup body scrapes and washes the outer wall of the filter screen, impurities on the outer wall of the filter screen are discharged from the blowoff valve channel along with water flow, thereby reach the back flush and scrape dual cleaning action, have easy operation, the practicality is strong, and the outward appearance is pleasing to the eye, need not to cut off the pipeline and just can reach effective washing, cleaning performance effect such as good.

Drawings

FIG. 1 is an exploded view of the present invention;

fig. 2 is a structural view of a first embodiment of the present invention;

FIG. 3 is a block diagram of a second embodiment of the present invention;

FIG. 4 is a structural diagram of the three-way valve body of the present invention;

FIG. 5 is a structural diagram of the valve cartridge of the present invention;

fig. 6 is a structural view of the filter assembly of the present invention.

Wherein, 1, decorating cover; 2. a screw; 3. a backwashing knob; 4. a flat clamp spring; 5. a valve stem; 6. a first seal ring; 7. a three-way valve body; 8. fixing a clamp spring; 9. a housing; 10. a thread protecting sleeve; 11. a second seal ring; 12. a metal washer; 13. a gasket; 14. a valve core; 15. A third seal ring; 16. a fourth seal ring; 17. a filter screen framework; 18. scraping and washing the strips; 19. A fifth seal ring; 20. a sixth seal ring; 21. a filter screen; 22. a cup body; 23. a connecting member; 24. a seventh seal ring; 25. an open collar; 26. a blowoff valve; 27. scraping and washing the knob upper cover; 28. scraping and washing the knob; 29. a base; 30. a quick connector; 31. a blowoff valve knob; 32. buckling; 701. a valve stem mounting hole; 702. a second conduit; 703. a first conduit; 704. a third conduit; 141. a first flow aperture; 142. a fourth flow aperture; 143. a third flow aperture; 144. a second flow aperture; 171. a protrusion; 172. and a through hole.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

As shown in fig. 1, a pre-filter according to a preferred embodiment of the present invention includes: back flush knob 3 subassembly, switch-on subassembly, filtering component, scrape washing knob 28 subassembly and blowdown subassembly, back flush knob 3 subassembly includes: backwash knob 3, valve rod 5 and case 14, case 14 includes: first runner, second runner and valve rod 5 mounting groove, first discharge orifice 141 and second discharge orifice 144 are seted up at first runner both ends, third discharge orifice 143 and fourth discharge orifice 142 are seted up at second runner both ends, back flush knob 3 connects the one end of valve rod 5, on the valve rod 5 mounting groove is connected to the other end of valve rod 5, the subassembly that switches on includes three-way valve body 7, set up first pipeline on the three-way valve body 7, the second pipeline, third pipeline and valve rod 5 mounting hole, case 14 sets up at the inside cavity of three-way valve body 7, valve rod 5 wears to locate valve rod 5 hole, the filter assembly includes: filter screen skeleton 17, filter screen 21, scrape and wash strip 18 and cup 22, the rotatable connection in third orifice 143 of filter screen skeleton 17 one end, the third runner is seted up in inside to filter screen skeleton 17 fretwork, third runner one end and the corresponding setting of third orifice 143, the filter screen 21 cladding is in the periphery of filter screen skeleton 17, cup 22 inner wall sets up a plurality of strips 18 of washing of scraping, cup 22 cover is established in filter screen 21's periphery, cup 22 one end and third pipe connection, connecting piece 23 mounting hole has been seted up to the cup 22 other end, filter screen 21's periphery with scrape and wash the contact of strip 18, scrape and wash knob 28 subassembly includes: scrape and wash knob 28 and connecting piece 23, scrape and wash the inside cavity of knob 28, scrape and wash the 28 lateral walls of knob and offer the valve mounting hole, connecting piece 23 one end is connected with filter screen skeleton 17 one end, and the fourth runner is offered to connecting piece 23 inside, and the fourth runner corresponds the setting with the third runner, and inside connecting piece 23 mounting hole was worn to establish by connecting piece 23, the blowdown subassembly included: blowoff valve 26 and blowoff valve 26 knob, blowoff valve 26 sets up the cavity in the inside of scraping and washing knob 28, and blowoff valve 26 includes: valve pipe and valve, the connecting piece 23 other end is connected to valve pipe one end, and the valve corresponds the setting with the valve mounting hole, and 26 knobs of blowoff valve wear to establish the valve mounting hole and are connected with the valve.

It should be noted that, by adopting a simple and effective ball valve structure, the flow direction of the inlet water is changed by the turning of the ball valve, so as to flush the holes of the filter screen 21, the third flow hole 143 is always connected with the third flow channel correspondingly through the flow hole in the back flush knob 3, when the back flush knob 3 is rotated to drive the valve rod 5 to drive the valve core 14 to rotate, the first flow hole 141 is connected with the first conduit 703 correspondingly, at this time, the second flow hole 144 is connected with the gap between the cup body 22 and the filter screen 21 correspondingly, the fourth flow hole 142 is connected with the second conduit 702 correspondingly, and at the same time, the blowoff valve 26 is closed, at this time, the water flows to the first flow channel through the first conduit 703, flows into the gap between the cup body 22 and the filter screen 21, penetrates into the third flow channel through the filter screen 21, and then flows out of the filter from the second conduit 702, when the back flush, the first conduit 703 is correspondingly connected to the fourth flow hole 142, the first flow hole 141 is correspondingly matched with the second conduit 702, and the blowoff valve 26 is opened, at this time, water flows through the second flow channel of the first conduit 703, such as the valve core 14, and then flows into the third flow channel, and then flows into the gap between the cup body 22 and the filter screen 21 through the filter screen 21, and then flows into the fourth flow channel and flows out of the device.

In addition, the cleaning and sewage discharging can be realized only by rotating the knob, impurities on the outer wall of the filter screen 21 are scraped through the scraping function, the impurities in the holes of the filter screen 21 are flushed out through backwashing, and the impurities sink to the sewage outlet at the lower end of the filter under the action of the water pressure flushing force, so that the multiple cleaning and sewage discharging effects from inside to outside and from outside to below are achieved.

Preferably, the backwashing knob 3 component is in a ball valve ball shape, a screw hole is formed in the center of the backwashing knob 3, a screw 2 penetrates through the screw hole, a decoration cover 1 is installed on the screw 2, the screw 2 penetrates through the backwashing component to be connected to a valve rod 5, and the valve rod 5 is sleeved with a leveling clamp spring 4.

It should be noted that the flat clamp spring 4 plays a limiting role to prevent the valve rod 5 from moving radially in the mounting hole of the valve rod 5.

Preferably, a first sealing ring 6 is arranged at the joint of the mounting hole of the valve rod 5 and the valve rod 5.

The function of the seal ring is to prevent water leakage.

Preferably, the conducting assembly further comprises a shell 9, and the shell 9 covers the outer surface of the three-way valve body 7.

It should be noted that, the casing 9 is a hidden buckle type casing 9, which can protect the product body from being damaged by external factors and has good appearance.

Preferably, a first thread, a second thread and a third thread are respectively arranged on the first pipeline, the second pipeline and the third pipeline, wherein the first thread and the second thread are external threads, the pipeline ports of the first pipeline and the second pipeline are sequentially provided with a sealing gasket 13, a metal gasket 12 and a second sealing ring 11, and a thread protecting sleeve 10 is arranged on the first thread and the second thread.

It should be noted that the external threads of the first pipeline and the second pipeline are convenient to connect with an external device, the first pipeline is connected with a water inlet device, the second pipeline is connected with a filtered water outlet device, and the arrangement of the threads increases the adaptability and the universality of the device.

Preferably, a third sealing ring 15 is arranged on the third flow hole 143, a fourth sealing ring 16 is arranged at one end of the third flow passage connected with the third flow hole 143, and the third sealing ring 15 is in seamless contact with the fourth sealing ring 16.

It should be noted that the third orifice 143 is connected to the third flow channel by the third sealing ring 15 and the fourth sealing ring 16, so as to prevent water leakage and achieve rotatable connection.

Preferably, a fourth thread is arranged at one end of the cup body 22, the fourth thread is an external thread, the fourth thread is screwed with the third thread, and a fifth sealing ring 19 is arranged at the joint of the cup body 22 and the three-way valve body.

It should be noted that the cup 22 is connected with the tee pipe fitting by a thread, and the fifth sealing ring 19 is arranged at the joint, so that the reliability of connection is ensured, and water leakage is prevented.

Preferably, a sixth sealing ring 20 is arranged at the joint of the filter screen framework 17 and the valve core 14.

Preferably, a seventh sealing ring 24 and an opening collar 25 are sequentially arranged at the joint of the filter screen framework 17 and the connecting piece 23.

It should be noted that, the filter screen framework 17 and the connecting piece 23 are connected by inserting the protrusion 171 arranged at the bottom of the filter screen framework 17 into the fourth flow channel of the connecting piece 23, the seventh sealing ring 24 is arranged at the joint, which not only ensures the connection reliability, but also prevents water leakage, and the opening collar 25 ensures the connection reliability.

Preferably, one end of the fourth flow passage is provided with a fifth thread, one end of the valve pipe is provided with a sixth thread, the fifth thread is an internal thread, the sixth thread is an external thread, and the fifth thread and the sixth thread are connected in a screwed mode.

It should be noted that the connecting piece 23 is connected with the blowoff valve 26 through threads, so that the reliability of the connection is ensured.

Preferably, the scraping and washing knob 28 assembly further comprises a scraping and washing knob 28 upper cover 27, a base 29 and a quick plug, the scraping and washing knob 28 upper cover 27 is in a circular ring disc shape and is seamlessly sleeved on the outer side surface of the cup body 22, the outer edge of the scraping and washing knob 28 upper cover 27 is connected with one end of the scraping and washing knob 28, the other end of the scraping and washing knob 28 is connected with the base 29, a center hole is formed in the center of the base 29, and one end of the valve rod 5 penetrates through the center hole to be connected with the quick.

Preferably, a snap 32 is mounted at the connection of the knob of the waste valve 26 and the valve.

It should be noted that the drain switch adopts a knob type handle, and is fixedly connected with the valve through a buckle 32, so that the operation is simple and clear.

Preferably, a baffle is arranged at a gap between the cup body 22 and the filter screen 21, and the outer diameter of the baffle is larger than that of the upper end of the filter screen 21.

It should be noted that, as shown in fig. 3, when the first conduit 703 is connected to the fourth flow hole 142 and the first flow hole 141 is connected to the second conduit 702, a baffle is disposed at a position corresponding to the second flow hole 144 and in a gap between the cup 22 and the filter mesh 21, and the baffle is configured to prevent water from flowing back to the second flow channel from the gap between the cup 22 and the filter mesh 21 to enter the second conduit 702 and pollute the pipeline when the flow rate of the inflow water is too high.

Preferably, one end of the filter screen framework 17 is provided with a protrusion 171, a flow passage is formed inside the protrusion 171, the protrusion 171 is connected to the third flow passage and holes are formed at two sides, and the protrusion 171 is inserted into the fourth flow passage.

It should be noted that, as shown in fig. 6, the filter screen 21 is coated on the side wall and the bottom of the filter screen framework 17, the filter screen 21 is designed to be a detachable structure, and after detachment, stubborn impurities in the filter screen 21 and the hanging rack can be cleaned, so that the service life of the product is prolonged.

It should be noted that, a convex-shaped protrusion 171 is disposed at the bottom of the filter screen 21, the protrusion 171 is connected to the third flow channel, two through holes 172 are disposed on the side wall, a part of the protrusion 171 is inserted into the fourth flow channel of the connector 23 and is fixedly connected, and the part of the protrusion 171 having the through holes 172 on both sides is not inserted into the fourth flow channel, so that the fourth flow channel does not block the through holes 172.

The utility model discloses an one of concrete embodiment:

the filtering work condition of the prefilter is shown as figure 2: domestic water enters the pre-filter through the first conduit 703 of the three-way valve body 7, then enters the first flow hole 141 in the valve core 14, flows to the gap between the cup body 22 and the filter screen 21 through the second flow hole 144 in the valve core 14, at this time, the blowoff valve 26 is in a closed state, then flows into the third flow channel inside the filter screen framework 17 through the filter screen 21, flows out of the valve core 14 through the third flow hole 143 and the fourth flow hole 142 in the valve core 14, and finally flows into the terminal pipeline through the third conduit 702 of the three-way valve body 7.

The utility model discloses an one of concrete embodiment:

the cleaning working condition of the front filter is shown in figure 3: under the condition that a tail end pipeline is not in a working state, the blowoff valve knob 31 rotates 90 degrees clockwise, the blowoff valve 26 is opened, then the back flush knob 3 rotates 180 degrees, at the moment, the back flush knob 3 drives the valve rod 5 and the valve core 14 to rotate 180 degrees, the fourth flow hole 142 in the valve core 14 is matched with the first conduit 703 of the three-way valve body 7, the first flow hole 141 in the valve core 14 is matched with the second conduit 702 of the three-way valve body 7, water flows into the pre-filter through the first conduit 703 of the three-way valve body 7, then enters the fourth flow hole 142 in the valve core 14, passes through the third flow hole 143 in the valve core 14 and the third flow channel in the filter screen framework 17, water flows into a gap between the cup body 22 and the filter screen 21 from the filter holes in the filter screen 21, meanwhile, the scraping and washing knob 28 rotates clockwise and counterclockwise alternately, the filter screen framework 17 is driven to rotate through, impurities coated on the outer wall of the filter 21 and impurities in the filter holes flow into the fourth flow channel from the through holes 172 on both sides of the protrusion 171 along with water flow, and are discharged through the blowoff valve 26, thereby achieving the double cleaning function of back washing and scraping.

The utility model has the advantages of as follows:

1. the pipeline does not need to be cut off: the cleaning and sewage discharging can be realized without cutting off the pipeline in the cleaning and sewage discharging process, and the labor and the time are saved.

2. The operation is simple: the cleaning and pollution discharge can be realized only by rotating the knob.

3. Scraping and backwashing multiple cleaning technology: impurities on the outer wall of the filter screen are scraped through the scraping and washing function, the impurities in the filter screen holes are washed out through back washing, and the impurities sink to a drain outlet at the lower end of the filter under the action of water pressure impact force, so that multiple cleaning and sewage discharging effects from inside to outside and from outside to below are achieved.

4. The backwashing technology of the ball valve structure comprises the following steps: adopt simple effectual ball valve structure, turn to through the valve ball, change the inflow flow direction to reach the effect of washing and filtering the mesh.

5. Can dismantle the filter screen: the filter screen designs into detachable construction, can wash stubborn impurity in filter screen and the stores pylon after the dismantlement, reinforcing product life.

6. The shell is beautiful: the hidden buckle type machine body shell is adopted, so that the product main body can be protected from being damaged by external factors, and the product is attractive and attractive.

7. Knob type handle: the back washing and sewage draining switch adopts a knob type handle, and the operation is simple and clear.

To sum up, the embodiment of the utility model provides a disclose leading filter, a serial communication port, include: the backwashing knob component, the conduction component, the filtering component, the scraping knob component and the sewage discharge component change the flow direction from the original flow-cup body-filtering screen outer wall-filtering screen inner hole-valve core-flow direction terminal pipeline flow direction to the flow-valve core-filtering screen inner hole-filtering screen outer wall-cup body-sewage discharge outlet flow direction by rotating the backwashing knob, and impurities in the original filtering screen small holes are flushed out along with the flow of water to the filtering screen outer wall under the action of water flow pressure.

The above is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and replacements can be made without departing from the counting principle of the present invention, and these modifications and replacements should also be regarded as the protection scope of the present invention.

Claims

1. A pre-filter, comprising: back flush knob subassembly, switch-on subassembly, filtering component, scrape and wash knob subassembly and blowdown subassembly, back flush knob subassembly includes: back flush knob, valve rod and case, the case includes: the valve comprises a first flow passage, a second flow passage and a valve rod mounting groove, wherein a first flow hole and a second flow hole are formed in two ends of the first flow passage, a third flow hole and a fourth flow hole are formed in two ends of the second flow passage, a backwashing knob is connected with one end of a valve rod, the other end of the valve rod is connected with the valve rod mounting groove, the conduction assembly comprises a three-way valve body, a first pipeline, a second pipeline, a third pipeline and a valve rod mounting hole are formed in the three-way valve body, the valve core is arranged in a cavity in the three-way valve body, and the valve rod penetrates through the valve rod hole;

the filter assembly includes: the filter comprises a filter screen framework, a filter screen, scraping and washing strips and a cup body, wherein one end of the filter screen framework is rotatably connected with a third flow hole, the filter screen framework is hollowed and is internally provided with a third flow channel, one end of the third flow channel is arranged corresponding to the third flow hole, the filter screen is coated on the periphery of the filter screen framework, the inner wall of the cup body is provided with a plurality of scraping and washing strips, the cup body is sleeved on the periphery of the filter screen, one end of the cup body is connected with the third pipeline, the other end of the cup body is provided with a connecting piece mounting hole, and the periphery of the filter screen is in contact with the scraping;

the scrub knob assembly includes: the scraping and washing knob is hollow, a valve mounting hole is formed in the side wall of the scraping and washing knob, one end of the connecting piece is connected with one end of the filter screen framework, a fourth flow channel is formed in the connecting piece, the fourth flow channel and the third flow channel are arranged correspondingly, and the connecting piece penetrates through the connecting piece mounting hole;

the soil exhaust assembly includes: blowoff valve and blowoff valve knob, the blowoff valve sets up scrape and wash the inside cavity of knob, the blowoff valve includes: valve pipe and valve, valve pipe one end is connected the connecting piece other end, the valve with the valve mounting hole corresponds the setting, the blowoff valve knob wears to establish the valve mounting hole with the valve is connected.

2. The prefilter of claim 1 wherein said back flush knob assembly is in the shape of a ball valve, said back flush knob is centrally provided with a threaded hole, a screw is inserted into said threaded hole, a decorative cover is mounted on said screw, said screw passes through said back flush assembly and is connected to said valve stem, and said valve stem is sleeved with a flat clamp spring.

3. The prefilter of claim 1 wherein a first seal ring is disposed at the junction of said stem mounting hole and said stem, and a retaining snap spring is disposed at the junction of said stem and said plug.

4. The prefilter of claim 1 wherein said lead-through assembly further comprises a housing, said housing covering an outer surface of said three-way valve body.

5. The prefilter of claim 1 wherein said first, second and third pipes are provided with first, second and third threads, respectively, wherein said first and second threads are external threads, wherein said first and second threads are provided with gaskets, metal gaskets, second gaskets, and wherein said first and second threads are provided with thread protection sleeves.

6. The prefilter of claim 1 wherein a third seal is disposed in said third flowbore and a fourth seal is disposed in said third flow passage at the end of said third flowbore which is connected to said third flowbore, said third seal being in seamless contact with said fourth seal.

7. The prefilter of claim 5 wherein a fourth thread is provided at one end of said bowl, said fourth thread being an external thread, said fourth thread being in threaded engagement with said third thread, and a fifth seal being provided at the junction of said bowl and said three-way valve body.

8. The prefilter of claim 1 wherein a sixth gasket is provided at the junction of said screen frame and said core.

9. The prefilter of claim 1 wherein a seventh gasket and an open collar are disposed in sequence at the junction of said screen frame and said connector.

10. The prefilter of claim 1 wherein a fifth thread is provided at one end of said fourth flow path and a sixth thread is provided at one end of said valve tube, wherein said fifth thread is an internal thread and said sixth thread is an external thread, and wherein said fifth thread and said sixth thread are threadedly connected.

11. The pre-filter of claim 1, wherein the scraping knob assembly further comprises a scraping knob upper cover, a base and a quick plug, the scraping knob upper cover is in a circular disc shape and is seamlessly sleeved on the outer side surface of the cup body, the outer edge of the scraping knob upper cover is connected with one end of the scraping knob, the other end of the scraping knob is connected with the base, a center hole is formed in the center of the base, and one end of the valve rod penetrates through the center hole to be connected with the quick plug.

12. The prefilter of claim 1 wherein said drain knob is snap-fit to said valve at the junction thereof.

13. The prefilter of claim 1 wherein a baffle is disposed in the gap between said bowl and said screen, said baffle having an outer diameter greater than the outer diameter of the upper end of said screen.

14. The prefilter of claim 1 wherein said filter frame has a protrusion at one end, said protrusion having a flow channel therein, said protrusion being connected to said third flow channel and having holes at both sides, said protrusion being inserted into said fourth flow channel.