CN110124377B

CN110124377B - Front filter

Info

Publication number: CN110124377B
Application number: CN201910562937.0A
Authority: CN
Inventors: 胡效军; 陈志超
Original assignee: HAINING SHUIXIANG WATER PURIFICATION EQUIPMENT CO Ltd
Current assignee: HAINING SHUIXIANG WATER PURIFICATION EQUIPMENT CO Ltd
Priority date: 2019-06-26
Filing date: 2019-06-26
Publication date: 2024-05-03
Anticipated expiration: 2039-06-26
Also published as: CN110124377A

Abstract

The invention discloses a pre-filter, which comprises a shell, a filter assembly arranged in the shell, a water inlet for flushing liquid to flow into the filter assembly to flush dirt, and a first drain valve and a second drain valve which are arranged at two ends of the shell and are respectively communicated with the filter assembly. The pre-filter provided by the invention can alternatively open the first blow-down valve or the second blow-down valve to discharge the dirt from the first blow-down valve or the second blow-down valve. The first blow-down valve and the second blow-down valve are arranged at two ends of the shell, so that bidirectional blow-down is realized, the risk that blow-down cannot be realized due to damage of a single blow-down valve is reduced, the failure rate is low, and blow-down is smooth, and therefore, the reliability of blow-down of the pre-filter provided by the invention is high.

Description

Front filter

Technical Field

The invention relates to filtering equipment, in particular to a pre-filter.

Background

The existing tap water often causes secondary pollution due to rusting, leakage and other reasons of the pipeline, seriously damages the health of the body and the service life of subsequent equipment, and on the basis, a pre-filter is usually additionally arranged on an inlet pipeline of the tap water, so that impurities such as rust, sand mud, algae and the like in the tap water pipeline are removed by using the pre-filter.

The existing pre-filter comprises a shell, a filter screen and a blow-down valve, wherein the blow-down valve is usually arranged at the bottom end. During normal filtration, the drain valve is closed, raw water flows into the inner side from the outer side of the filter screen to realize raw water filtration, and impurities generated in the filtration process are adhered to the filter screen; when the filter screen is washed, the drain valve is opened, the washing liquid flows from the inner side of the filter screen to the outer side to wash the adhered impurities, and the washing liquid containing the impurities is discharged from the drain valve.

However, because the drain valve is usually only arranged at one end of the shell, the single drain valve is extremely easy to have faults such as incapability of being opened and the like due to corrosion and the like, and the reliability of drain is poor.

Therefore, how to improve the reliability of the pollution discharge of the existing pre-filter is a technical problem to be solved by the person skilled in the art.

Disclosure of Invention

Accordingly, the invention aims to provide a pre-filter which can realize bidirectional pollution discharge, and has the advantages of smooth pollution discharge and high pollution discharge reliability.

The specific scheme is as follows:

the invention provides a pre-filter comprising:

a housing;

A filter assembly disposed within the housing;

A water inlet for supplying a flushing liquid to flow into the filter assembly to flush dirt;

the first drain valve and the second drain valve are arranged at two ends of the shell and are respectively communicated with the filtering component and used for selectively discharging the washed dirt.

Preferably, the first blow-down valve is an electric ball valve and further comprises a controller which is connected with the electric ball valve and used for controlling the electric ball valve to be opened and closed.

Preferably, the method further comprises:

A water outlet for discharging the purified water;

the water inlet pressure detection piece is arranged at the water inlet and used for detecting the water inlet pressure;

the water outlet pressure detection part is arranged at the water outlet and used for detecting the water pressure;

The water inlet pressure detection part and the water outlet pressure detection part are connected with the controller, and the controller controls the electric ball valve to be opened when the difference between the water inlet pressure and the water outlet pressure reaches a preset difference value according to signals sent by the water inlet pressure detection part and the water outlet pressure detection part.

Preferably, the method further comprises:

the controller has a timer for recording the time of use of the filter assembly; the controller is used for controlling the opening of the electric ball valve when the service time of the filter assembly reaches the preset service time according to the signal sent by the timer.

Preferably, the method further comprises:

And the handheld terminal is connected with the controller and is provided with a cleaning button, and the electric ball valve is controlled to be opened when the controller receives a signal sent by the cleaning button.

Preferably, the method further comprises:

The dirt content detection part is connected with the controller and is arranged at the outlet of the electric ball valve and used for detecting the dirt content at the outlet of the electric ball valve; the controller is used for controlling the electric ball valve to be closed when the dirt content of the outlet of the electric ball valve is lower than the preset dirt content according to the dirt content detection part.

Preferably, the second blow-down valve is a manual ball valve and further comprises a blow-down switch which is arranged on the second blow-down valve and used for manually controlling the opening and closing of the second blow-down valve.

Preferably, a drain pipe penetrates through the filter assembly and is respectively communicated with the first drain valve and the second drain valve at two ends so as to enable dirty circulation.

Preferably, the housing comprises a housing body and a housing end cap connected to the housing body, the filter assembly comprising:

A filter screen;

The supporting framework is sleeved between the filter screen and the shell body;

the filter baffle is detachably fixed on one end of the filter screen, which is close to the second blowoff valve, and flushing fluid flowing between the filter screen and the supporting framework pushes the filter baffle to move so that the filter screen is far away from the shell end cover to conduct the center cavity of the water inlet and the filter screen.

Preferably, the filter assembly further comprises:

The washing elastic piece is sleeved on the periphery of the filter screen and used for assisting the reset of the filter screen, the inner side wall of the supporting framework 22 is provided with an abutting step surface abutting against the first end of the washing elastic piece, and one end, away from the filter baffle, of the filter screen is provided with an abutting flange abutting against the second end of the washing elastic piece.

Compared with the background art, the pre-filter provided by the invention comprises the first blow-down valve and the second blow-down valve, and dirty flushing liquid can flow to two ends of the shell. Alternatively, the first blow-down valve or the second blow-down valve is opened to discharge the dirt from the first blow-down valve or the second blow-down valve. The first blow-down valve and the second blow-down valve are arranged at two ends of the shell, so that bidirectional blow-down is realized, the risk that blow-down cannot be realized due to damage of a single blow-down valve is reduced, the failure rate is low, and blow-down is smooth, and therefore, the reliability of blow-down of the pre-filter provided by the invention is high.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present invention, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

FIG. 1 is a block diagram of a prefilter according to a first embodiment of the present invention;

FIG. 2 is an exploded view of FIG. 1;

FIG. 3 is a view showing an operation state of the prefilter of FIG. 1 when filtering raw water;

FIG. 4 is a view of the prefilter of FIG. 1 in operation during flushing of the filter assembly;

FIG. 5 is a view of the prefilter of FIG. 1 in operation with a first blow down valve to remove dirt;

FIG. 6 is another cross-sectional view of the prefilter of FIG. 1 when filtering raw water;

FIG. 7 is a block diagram of the end cap of the shell of FIG. 1;

FIG. 8 is a cross-sectional view of FIG. 7;

FIG. 9 is another cross-sectional view of FIG. 7;

FIG. 10 is a block diagram of the filter assembly of FIG. 1;

FIG. 11 is an exploded view of FIG. 10;

FIG. 12 is a block diagram of the upper pipe joint of FIG. 3;

Fig. 13 is a cross-sectional view showing a structure of a prefilter according to a second embodiment of the present invention.

The reference numerals are as follows:

The device comprises a shell body 11, a shell end cover 12, a lower shell 13, an upper shell 14, a filter assembly 2, a first blow-down valve 3, a blow-down pipe 4, a second blow-down valve 5, a blow-down switch 6, a main joint 7, a pressure regulating valve 8, a flowmeter rotor 9 and a controller 10;

a wireless communication module 101, a water inlet pressure detecting member 102, a water outlet pressure detecting member 103;

an end cap inlet 121, an end cap outlet 122, a spacer ring plate 123, an annular cavity 124, and a cylindrical cavity 125;

The filter screen 21, the supporting framework 22, the filter baffle 23, the flushing elastic piece 24, the lower connecting sleeve 25, the lower pipe joint 26, the upper pipe joint 27, the limiting ring 28, the water inlet quick connector 291 and the water outlet quick connector 292;

A limit groove 271 and an annular mounting groove 272;

a water inlet detection port 2911 and a water outlet detection port 2921;

A water inlet 51 and a water outlet 52.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In order that those skilled in the art will better understand the present invention, the following description will be given in detail with reference to the accompanying drawings and specific embodiments.

Referring to fig. 1 to 12, fig. 1 is a block diagram of a prefilter according to a first embodiment of the present invention; FIG. 2 is an exploded view of FIG. 1; FIG. 3 is a view showing an operation state of the prefilter of FIG. 1 when filtering raw water; FIG. 4 is a view of the prefilter of FIG. 1 in operation during flushing of the filter assembly; FIG. 5 is a view of the prefilter of FIG. 1 in operation with a first blow down valve to remove dirt; FIG. 6 is another cross-sectional view of the prefilter of FIG. 1 when filtering raw water; FIG. 7 is a block diagram of the end cap of the shell of FIG. 1; FIG. 8 is a cross-sectional view of FIG. 7; FIG. 9 is another cross-sectional view of FIG. 7; FIG. 10 is a block diagram of the filter assembly of FIG. 1; FIG. 11 is an exploded view of FIG. 10; fig. 12 is a structural view of the upper pipe joint of fig. 3.

The invention provides a prefilter, which comprises a shell, a filter assembly 2, a first blow-down valve 3 and a second blow-down valve 5.

In a first embodiment, the present view of fig. 1 is followed by a first blow-down valve 3 at the top of the housing and a second blow-down valve 5 at the bottom of the housing.

The casing includes shell body 11 and shell end cover 12, and shell body 11 has the die cavity that holds that is used for holding filter module 2, and shell end cover 12 installs in the opening part that holds the die cavity, preferably adopts threaded connection between shell body 11 and the shell end cover 12, still can add the sealing washer between the contact surface of shell body 11 and shell end cover 12, prevents that the casing from leaking.

The invention further comprises a water inlet 51 for the flushing liquid to flow into the filter assembly 2, so that the flushing liquid adheres to dirt on the filter assembly 2. The water inlet 51 is arranged on the main joint 7, and the main joint 7 is connected with the shell.

The filter assembly 2 for washing dirt is arranged in the shell, the filter assembly 2 is communicated with the water inlet 51, and when raw water is filtered, the raw water flows into the filter assembly 2 from the water inlet 51; when the filter assembly 2 is rinsed, the rinsing liquid flows into the filter assembly 2 through the water inlet 51. Of course, the raw water may be tap water having a certain pressure, and the flushing liquid may be purified water having a certain pressure and having a small impurity content.

Preferably, the filter assembly 2 comprises a filter screen 21, a support skeleton 22, a filter baffle 23 and a flushing elastic member 24.

The filter screen 21 includes filtering the curb plate and filtering the bottom plate, and filtering the curb plate and being cylindric, and filtering the curb plate and have a plurality of filtration holes, filtering the bottom plate and setting firmly in the bottom of filtering the curb plate. The supporting framework 22 is positioned between the filter screen 21 and the shell body 11 and fixed relative to the shell body 11. The supporting frame 22 is cylindrical, and the side surface is provided with a plurality of drain holes penetrating in the thickness direction, wherein the drain holes are used for discharging dirt. Preferably, a frame sealing ring is arranged between the outer side surface of the supporting frame 22 and the shell body 11, and is flush with the bottom of the filter screen 21 during filtering, so that raw water is prevented from flowing into the bottom of the supporting frame 22 from the drain hole, and the pollution of the raw water at the bottom of the supporting frame 22 is avoided.

A filtering baffle 23 is installed at the filtering bottom plate of the filtering net 21, and specifically, the filtering baffle 23 is fixed to the bottom of the filtering bottom plate through a set screw. A stopper seal ring is provided between the filtering baffle 23 and the inner side wall of the supporting frame 22 so that the washing liquid flowing between the filtering screen 21 and the supporting frame 22 can apply a force to the filtering baffle 23.

A flushing elastic piece 24 is arranged between the inner side surface of the supporting framework 22 and the outer peripheral surface of the filter screen 21, the bottom of the flushing elastic piece 24 is abutted against an abutting step surface arranged on the inner side of the supporting framework 22, the top end of the flushing elastic piece 24 is abutted against an abutting flange arranged on the top end of the filter screen 21, the abutting flange is cylindrical, and the outer diameter of the abutting flange is larger than that of the filter screen 21. And a framework flange sealing ring propped against the supporting framework 22 is fixedly arranged on the periphery of the propping flange so that the propping flange is propped against the supporting framework 22, and the flange sealing ring seals a gap between the propping flange and the supporting framework 22 to prevent flushing fluid from leaking.

Correspondingly, an isolating ring plate 123 is arranged on one side of the shell end cover 12, which is close to the filter screen 21, an annular cavity 124 is formed between the outer peripheral surface of the isolating ring plate 123 and the inner side surface of the shell end cover 12, a columnar cavity 125 is formed around the inner side surface of the isolating ring plate 123, the annular cavity 124 is communicated with the water inlet 51, and the columnar cavity 125 is communicated with the water outlet 52. Further, the shell end cover 12 further has an end cover inlet 121 communicating with the water inlet 51 and an end cover outlet 122 communicating with the water outlet 52, the end cover inlet 121 and the end cover outlet 122 are coaxially arranged, the end cover outlet 122 is communicated with the water outlet 52, and a cavity formed by the outer peripheral surface of the end cover outlet 122 and the inner side surface of the end cover inlet 121 is communicated with the water inlet 51, so that the end cover inlet 121 and the end cover outlet 122 are independently arranged.

Referring to fig. 3, when raw water is filtered, the flushing elastic member 24 is in a natural state, the filter screen 21 is abutted against the shell end cover 12, specifically, the top end of the filter screen 21 is abutted against the isolating ring plate 123, raw water flowing in from the water inlet 51 flows into the annular cavity 124 through the end cover inlet 121, raw water in the annular cavity 124 flows into the filter screen 21 from the outer side of the filter screen 21, filtered clean water flows into the columnar cavity 125, and finally flows into the water outlet 52 through the end cover outlet 122 to be discharged.

Referring to fig. 4 and 5, when the dirt is washed, the washing liquid flows to the bottom of the filter screen 21, a certain acting force is applied to the filter baffle 23 by the washing liquid, when the acting force is too large, the filter baffle 23 drives the filter screen 21 to move downwards relative to the support framework 22 until the abutting flange abuts against the top end of the support framework 22, the filter screen 21 is separated from contact with the isolating ring plate 123, the washing liquid is blocked from flowing to the bottom of the filter screen 21, the annular cavity 124 and the columnar cavity 125 are communicated with the inner side of the filter screen 21, the washing liquid flowing in from the water inlet 51 sequentially flows into the inner side of the filter screen 21 through the end cover inlet 121 and the annular cavity 124, and is discharged from the outer side of the filter screen 21, the counter acting force is applied to the dirt, and the dirt overcomes the adhesion force until the dirt falls off from the filter screen 21, and further dirt cleaning is realized.

Of course, the structure of the filter assembly 2 is not limited thereto, and the use of other similar structures does not affect the achievement of the object of the present invention.

The first blow-down valve 3 and the second blow-down valve 5 are respectively arranged at two ends of the shell, and the first blow-down valve 3 and the second blow-down valve 5 are respectively communicated with the filter assembly 2, so that the flushed dirt can be alternatively discharged from the first blow-down valve 3 and the second blow-down valve 5. It should be noted that, when the raw water is filtered, both the first drain valve 3 and the second drain valve 5 are in a closed state; when the dirt is washed, the first blow-down valve 3 and the second blow-down valve 5 are alternatively opened.

Preferably, the first blow-down valve 3 is an electric ball valve, so that the first blow-down valve 3 is conveniently and automatically controlled to be opened and closed, and the use is convenient; correspondingly, the second blow-down valve 5 is a manual ball valve, so that when the first blow-down valve 3 has accidents such as circuit failure or jamming, a user can utilize the second blow-down valve 5 to carry out manual blow-down, and reliable and effective blow-down is ensured.

Correspondingly, the invention further comprises a controller 10 connected with the electric ball valve, and the controller 10 can control the electric ball valve to be opened and closed. It should be noted that, there are various ways in which the controller 10 controls the opening and closing of the electric ball valve.

First, it should be added that the present invention further includes a water outlet 52 for discharging purified water, and the water outlet 52 is provided on the main joint 7, as will be described in detail below.

The pollution discharge command can be determined by the pressure difference between the water inlet 51 and the water outlet 52, and it is understood that the present invention further includes a water inlet pressure detecting member 102 and a water outlet pressure detecting member 103. The intake pressure detecting member 102 is provided at the water inlet 51 for detecting the intake pressure. The outlet water pressure detecting member 103 is disposed at the outlet 52 for detecting the outlet water pressure. The intake water pressure detecting member 102 and the discharge water pressure detecting member 103 may each be a pressure sensor, but the type is not limited thereto.

The water inlet pressure detection part 102 and the water outlet pressure detection part 103 are connected with the controller 10, the water inlet pressure detection part 102 and the water outlet pressure detection part 103 send signals to the controller 10, the controller 10 analyzes and compares the received signals, when the difference between the water inlet pressure and the water outlet pressure reaches a preset difference value, the controller 10 generates a pollution discharge instruction and sends the pollution discharge instruction to the electric ball valve, and the electric ball valve is controlled to be opened to flush dirt; otherwise, the electric ball valve keeps the closed state continuously, so that raw water filtration is conveniently realized.

It should be noted that, the preset difference herein refers to the maximum pressure difference between the inlet water pressure and the outlet water pressure, which means that the filter screen 21 may be seriously blocked by dirt. Of course, the pressure detecting piece can be replaced by the flow detecting piece, and the automatic control of the opening and closing of the electric ball valve can be realized.

In this embodiment, in order to facilitate installation of the water inlet pressure detecting member 102 and the water outlet pressure detecting member 103, the shell end cover 12 is respectively provided with a water inlet detecting port 2911 and a water outlet detecting port 2921, wherein the water inlet detecting port 2911 is a cylindrical through hole, and accordingly, one end of the water inlet detecting port 2911 is communicated with the water inlet 51, the other end is provided with the water inlet quick connector 291, and the water inlet pressure detecting member 102 is installed in the water inlet quick connector 291. The water outlet detecting port 2921 is an L-shaped detecting hole, one end of the water outlet detecting hole is communicated with the water outlet 52, the water outlet quick connector 292 is arranged at the other end of the water outlet detecting hole, and the water outlet pressure detecting piece 103 is arranged in the water outlet quick connector 292. Of course, the mounting manner of the intake pressure detecting member 102 and the discharge pressure detecting member 103 is not limited thereto.

The blowdown instructions may also be obtained by setting the time of use, it being understood that the controller 10 has a timer capable of recording the time of use of the filter assembly 2, the timer also being capable of being used to set the time of use of the filter assembly 2. The controller 10 generates a pollution discharge instruction when the use time of the filter assembly 2 reaches a preset use time according to the signal transmitted by the timer. Specifically, when the timer records that the usage time of the filter assembly 2 reaches the preset usage time, or when the timer records that the set usage time of the filter assembly 2 is zero, the timer sends a signal to the controller 10, and the controller 10 generates a pollution discharge instruction to control the electric ball valve to be opened, so that the pollution is washed. For example, the filter assembly 2 may be rinsed once every 10 days using a timer setting, although the user may also set the duration of rinsing of the filter assembly 2.

The pollution discharge instruction can also be obtained through a handheld terminal, and it is understood that the invention further comprises a handheld terminal connected with the controller 10, the handheld terminal is provided with a cleaning button, the cleaning button is pressed, the handheld terminal sends a pulse signal to the controller 10, and the controller 10 produces the pollution discharge instruction according to the received pulse signal, controls the electric ball valve to be opened, and realizes the flushing of the pollution.

It should be noted that, the handheld terminal may be a device such as a mobile phone, a tablet or a computer, and a wireless communication module 101 is further added between the handheld terminal and the controller 10, so that wireless communication between the handheld terminal and the controller 10 is achieved. Of course, the working state of the electric ball valve or the working state of each detection piece can be fed back to the controller 10, the controller 10 gathers information and then sends the information to the handheld terminal, so that the handheld terminal can count and track key references such as water inlet pressure, water outlet pressure, cleaning time and flow conveniently, the cleaning effect can be monitored conveniently, an accurate and reliable cleaning plan can be generated, and the user experience is improved.

Of course, the manner of controlling the automatic start of the electric ball valve is not limited to the above three.

In order to further improve the automation degree, the invention further comprises a dirt content detection member connected with the controller 10, wherein the dirt content detection member is arranged at the outlet of the electric ball valve, so that the dirt content at the outlet of the electric ball valve can be detected by using the dirt content detection member. The soil content detecting member may be a water quality detector, which is not limited herein. When the dirt content at the outlet of the electric ball valve is lower than the preset dirt content, which means that the filter assembly 2 is completely cleaned, the dirt content detection part sends a signal to the controller 10, and the controller 10 controls the electric ball valve to be closed according to the signal sent by the dirt content detection part, so that the dirt cleaning is automatically stopped; otherwise, continuing to clean dirt. Obviously, the dirty content detection piece can realize electric ball valve self-closing, and degree of automation is high, experiences and feels good.

It can be understood that the invention also comprises a sewage switch 6 arranged on the second sewage valve 5, and the sewage switch 6 is touched manually, so that the second sewage valve 5 is controlled to be opened and closed manually, the sewage valve is used when the first sewage valve 3 fails, the sewage is conveniently and smoothly discharged, the failure rate is small, and the sewage is reliable.

Correspondingly, the invention also comprises a lower housing 13 fixedly arranged at the bottom of the housing body 11, the lower housing 13 is approximately conical, the large-diameter end of the lower housing 13 is abutted against the housing body 11, and the second blow-down valve 5 is arranged at the bottom of the lower housing 13. The center of the bottom of the shell body 11 is provided with a lower connecting hole for communicating the sewage drain pipe 4 with the inlet of the second sewage drain valve 5, a lower connecting sleeve 25 is arranged in the lower connecting hole, the outer circumferential surface of the lower connecting sleeve 25 is provided with an annular groove, an O-shaped sealing ring which props against the lower connecting hole to form a sealing structure is arranged in the annular groove, and meanwhile, the outer circumferential surface of the lower connecting sleeve 25 is also clamped with the lower housing 13, so that the lower connecting sleeve 25 is connected with the second sewage drain valve 5 and the lower housing 13.

Further, a lower pipe joint 26 is arranged in the lower connecting sleeve 25, an O-shaped sealing ring which is propped against the inner side surface of the lower connecting sleeve 25 to form a sealing structure is arranged on the outer peripheral surface of the pipe joint 26, and the inner side surface of the lower pipe joint 26 is in threaded connection with the second blow-down valve 5. The top end of the lower pipe joint 26 is lower than the top end of the lower connecting sleeve 25, and the lower connecting sleeve 25 is provided with an abutting annular plate which abuts against the supporting framework 22.

To achieve bi-directional drainage, in this particular embodiment, the invention further comprises a drain pipe 4 passing through the filter assembly 2, the two ends of the drain pipe 4 being in communication with the first drain valve 3 and the second drain valve 5, respectively, so that the dirt can be drained from either the first drain valve 3 or the second drain valve 5. The sewage drain pipe 4 is hollow and tubular. The drain pipe 4 sequentially passes through the center of the filter screen 21 and the shell end cover 12, correspondingly, the shell end cover 12 is provided with a drain hole, the drain hole is provided with an upper pipe joint 27, the outer peripheral surface of the upper pipe joint 27 is in clearance fit with the inner side surface of the drain hole, the inner side surface of the upper pipe joint 27 is connected with the first drain valve 3 in a threaded connection mode, and the inner side surface of the upper pipe joint 27 is in clearance fit with the drain pipe 4. In addition, a limiting protrusion and a limiting groove 271 for limiting the relative rotation of the upper pipe joint 27 and the first blow-down valve 3 are arranged between the upper pipe joint 27 and the first blow-down valve 3, specifically, the limiting groove 271 is a U-shaped limiting groove arranged at one end of the upper pipe joint 27 close to the first blow-down valve 3, and the limiting protrusion is a U-shaped limiting protrusion arranged on the first blow-down valve 3. Two sets of mutually symmetrical limit protrusions and limit grooves 271 are specifically arranged between the upper pipe joint 27 and the first blow-down valve 3.

In order to prevent dirt leakage, a sealing ring can be additionally arranged between the drain pipe 4 and the upper pipe joint 27, correspondingly, an annular mounting groove 272 for mounting the sealing ring is arranged in the upper pipe joint 27, and an O-shaped sealing ring is arranged in the annular mounting groove 272.

Further, the invention also comprises a dirt tube sealing member arranged between the filter assembly 2 and the dirt discharge tube 4, so that dirt is prevented from flowing into the filter assembly 2 from a gap between the filter assembly 2 and the dirt discharge tube 4. The dirty tube seal may be a rubber seal, and is not limited herein.

Furthermore, the invention also comprises a limiting ring 28 arranged in the center of the filter assembly 2, wherein the limiting ring 28 is provided with a limiting hole for the drain pipe 4 to pass through, so that the position of the drain pipe 4 is prevented from being changed, and the drain pipe 4 is ensured to be reliably connected with the first drain valve 3. Specifically, the limiting ring 28 is fixed on the inner wall of the filter screen 21 through four connecting ribs. Preferably, the drain pipe 4 is arranged coaxially with the filter screen 21.

In addition, the invention also comprises a main joint 7 with a water inlet 51 and a water outlet 52, wherein the water inlet 51 and the water outlet 52 are respectively arranged at two ends of the main joint 7, and the water inlet 51 and the water outlet 52 are independently arranged, so that purified water pollution is avoided. Preferably, a pressure regulating valve 8 is added to the water inlet 51, and the pressure regulating valve 8 can be manually regulated so as to regulate the water inlet pressure of the water inlet 51 within a certain range. The water outlet 52 can be additionally provided with a flowmeter rotor 9 connected with the controller 10, the clean water discharged by the filter screen 21 pushes the flowmeter rotor 9 to rotate, the flowmeter rotor 9 sends a signal to the controller 10, and the controller 10 controls the flow of the water outlet 52.

In addition, the invention also comprises an upper housing 14 covering the periphery of the first blow-down valve 3 for protecting the first blow-down valve 3.

The controller 10 includes a signal receiving portion for receiving an electric signal transmitted from a detecting element such as a pressure detecting element, a flow rate detecting element, or a timer, a signal determining portion electrically connected to the receiving portion for determining whether or not the signal received by the receiving portion is a trigger signal, and a signal transmitting portion electrically connected to the signal determining portion for transmitting a determination signal generated by the signal determining portion to an executing element such as the first drain valve 3. The specific arrangement modes of the signal receiving part, the signal judging part and the signal transmitting part can refer to the prior art; in the invention, the application scenes of the three are only changed, and the invention does not substantially improve the application scenes.

Obviously, the controller 10 having this structure is widely applied to existing automatic control devices, such as MCUs, DSPs, or singlechips. The key point of the present invention is that the controller 10 combines each sensing element with each wire executing element.

Referring to fig. 12, fig. 13 is a cross-sectional view of a prefilter according to a second embodiment of the present invention.

In a second embodiment, the present view of fig. 12 is followed, the first blow-down valve 3 being located at the bottom of the housing and the second blow-down valve 5 being located at the top of the housing. Correspondingly, the drain pipe 4 is fixedly connected with the second drain valve 5. The structure of the filter assembly 2 remains unchanged and still achieves the objects of the invention.

In combination, the pre-filter provided by the invention can alternatively open the first blow-down valve 3 or the second blow-down valve 5 to discharge the dirt from the first blow-down valve 3 or the second blow-down valve 5. The first blow-down valve 3 and the second blow-down valve 5 are arranged at two ends of the shell, so that bidirectional blow-down is realized, the risk that blow-down cannot be realized due to damage of a single blow-down valve is reduced, the failure rate is low, and blow-down is smooth, and therefore, the reliability of blow-down of the pre-filter provided by the invention is high.

The foregoing has outlined rather broadly the more detailed description of the prefilter of the present invention, and the principles and embodiments of the present invention have been described herein with reference to specific examples, the above examples being provided to facilitate an understanding of the method of the present invention and the core concepts thereof; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present invention, the present description should not be construed as limiting the present invention in view of the above.

Claims

1. A pre-filter, comprising:

a housing;

A filter assembly (2) disposed within the housing;

A water inlet (51) for flushing liquid flowing into the filter assembly to flush dirt;

the first drain valve (3) and the second drain valve (5) are arranged at two ends of the shell and are respectively communicated with the filter assembly (2) and used for alternatively discharging the washed dirt;

A drain pipe (4) passing through the filter assembly (2) and two ends of which are respectively communicated with the first drain valve (3) and the second drain valve (5) for circulating dirty water;

a limiting ring (28) arranged at the center of the filtering assembly (2), wherein the limiting ring (28) is provided with a limiting hole for the sewage drain pipe (4) to pass through;

the housing comprises a housing body (11) and a housing end cover (12) connected with the housing body (11), and the filter assembly (2) comprises:

a filter screen (21);

a supporting framework (22) sleeved between the filter screen (21) and the shell body (11);

A filtering baffle plate (23) detachably fixed at one end of the filtering net (21) close to the second blow-down valve (5), wherein flushing fluid flowing between the filtering net (21) and the supporting framework (22) is used for pushing the filtering baffle plate (23) to move so that the filtering net (21) is far away from the shell end cover (12) to conduct the water inlet (51) and the central cavity of the filtering net (21);

The washing elastic piece (24) is sleeved on the periphery of the filter screen (21) and used for assisting the reset of the filter screen (21), an abutting step surface abutting against the first end of the washing elastic piece (24) is arranged on the inner side wall of the supporting framework (22), and an abutting flange abutting against the second end of the washing elastic piece (24) is arranged at one end, far away from the filter baffle (23), of the filter screen (21).

2. The prefilter of claim 1, wherein the first drain valve (3) is an electrically operated ball valve, further comprising a controller (10) connected to the electrically operated ball valve for controlling the opening and closing of the electrically operated ball valve.

3. The pre-filter of claim 2, further comprising:

A water outlet (52) for discharging the purified water;

A water inlet pressure detecting member (102) provided at the water inlet (51) and detecting a water inlet pressure;

a water outlet pressure detecting member (103) provided at the water outlet (52) and configured to detect a water pressure;

The water inlet pressure detection part (102) and the water outlet pressure detection part (103) are connected with the controller (10), and the controller (10) controls the electric ball valve to be opened when the difference between the water inlet pressure and the water outlet pressure reaches a preset difference value according to the signals sent by the water inlet pressure detection part (102) and the water outlet pressure detection part (103).

4. The pre-filter of claim 2, further comprising:

The controller (10) is provided with a timer used for recording the service time of the filter assembly (2), and the controller (10) is used for controlling the opening of the electric ball valve when the service time of the filter assembly (2) reaches the preset service time according to a signal sent by the timer.

5. The pre-filter of claim 2, further comprising:

and the handheld terminal is connected with the controller (10) and is provided with a cleaning button, and when the controller (10) receives a signal sent by the cleaning button, the electric ball valve is controlled to be opened.

6. The pre-filter of claim 2, further comprising:

The dirty content detection piece is connected with the controller (10) and is arranged at the outlet of the electric ball valve and used for detecting the dirty content at the outlet of the electric ball valve; the controller (10) is used for controlling the electric ball valve to be closed when the dirt content at the outlet of the electric ball valve is lower than the preset dirt content according to the dirt content detection part.

7. The prefilter of any one of claims 1 to 6, wherein the second drain valve (5) is a manual ball valve, further comprising a drain switch (6) provided to the second drain valve (5) and adapted to manually control the opening and closing of the second drain valve (5).