CN220696021U - Backwashing filter - Google Patents

Abstract

The utility model provides a backwashing filter, which belongs to the technical field of filters and comprises the following components: the filter comprises a tank body and a filter element, wherein an opening is formed in the top of the tank body, a cover body is arranged at the opening, a plurality of slots are formed in the tank body, and a mounting opening at the upper end of each slot is in a tapered structure from top to bottom; the filter element is inserted into the slot, the installation end of the filter element is sleeved with a sealing ring, the outer diameter of the sealing ring is gradually reduced from top to bottom, and the outer surface of the sealing ring is tightly attached to the inner wall of the installation opening of the slot; when the filter element is used, the filter element is inserted into the slot, the sealing ring realizes the sealing between the filter element and the slot, the conical structure with big top and small bottom is arranged at the mounting opening of the sealing ring and the slot, the installation is convenient, the width of the sealing ring is larger, the sealing ring is prevented from being worn and falling into the backwash filter after long-time use, and the use safety is ensured; the backwash filter provided by the embodiment solves the problem that a sealing ring at the upper end of a filter element is easy to break in the prior art.

Description

Backwashing filter

Technical Field

The utility model relates to the technical field of filters, in particular to a backwashing filter.

Background

The plant slurry uses a back flushing filter, a filter element is arranged in the filter, an automatic control program is compiled, and the opening/closing of a pneumatic valve arranged on the filter is controlled, so that the feeding and discharging of the walnut kernel feed liquid are controlled; when the filter element needs to be washed, the washing procedure is executed through an automatic control procedure. In a set time period, according to the operation rule requirement, the on-site operator takes the filter element out of the filter once every day and uses the high-pressure water gun to wash.

In the prior art, 2 ring-shaped sealing rings are usually arranged in a groove at the upper end of the filter element, and in order to achieve a sealing effect, the sealing rings protrude out of the groove, and the sealing rings are easy to break and fall into the filter in the process of disassembling the filter element after being used for many times.

Disclosure of Invention

Therefore, the utility model aims to solve the technical problem that the sealing ring at the upper end of the filter element is easy to break, so as to provide a backwashing filter.

In order to solve the above technical problems, the present utility model provides a backwash filter, comprising:

the tank body is provided with an opening at the top, a cover body is arranged at the opening, a plurality of slots are arranged in the tank body, and the mounting port at the upper end of each slot is in a tapered structure from top to bottom;

the filter core is inserted in the slot, the installation pot head of filter core is equipped with the sealing washer, the external diameter of sealing washer from the top down reduces gradually, the surface of sealing washer with the installation mouth inner wall of slot closely laminates.

Optionally, the installation end of filter core evenly is provided with the spacing arch of radially outwards extending, be provided with on the installation mouth of slot with spacing protruding joint complex spacing draw-in groove.

Optionally, the fixed end of the filter element is further provided with an extending edge extending upwards, and the extending edge is provided with an operation hole.

Optionally, the jar body from the top down has set gradually discharge gate, feed inlet and drain, be provided with the flushing fluid entry on the lid, all be provided with the governing valve on drain, feed inlet, discharge gate and the pipeline of flushing fluid entry, the governing valve is connected with the controlling means electricity.

Optionally, the regulating valve includes:

the valve body is arranged in the pipelines of the sewage outlet, the feeding hole, the discharging hole and the flushing liquid inlet and is provided with a fixed ring and a valve plate which can be opened and closed in a rotating way;

the cylinder is arranged outside pipelines of the sewage outlet, the feeding hole, the discharging hole and the flushing liquid inlet, the cylinder is electrically connected with the control device, the cylinder is connected with the fixed ring through the fixed rod, and the driving rod of the cylinder penetrates through the fixed ring to be connected with the valve plate and drives the valve plate to rotate through the driving rod.

Optionally, the fixed first trigger lever and the second trigger lever that is provided with on the actuating lever, first trigger lever with solid fixed ring place plane parallel arrangement, first trigger lever with first trigger lever sets up perpendicularly, be provided with first inductor and second inductor on the actuating lever, first inductor and second inductor with the controlling means electricity is connected, when the valve plate is opened, the end of first trigger lever with first inductor is close to, when the valve plate is closed, the end of second trigger lever with the second inductor is close to.

Optionally, a plurality of locking devices are uniformly arranged on the top of the tank body along the circumferential direction, and the cover body is locked by the locking devices.

Optionally, the locking device includes:

the screw is rotationally arranged on the outer side of the top of the tank body;

the hand wheel is sleeved on the screw rod and in threaded connection with the screw rod, and the bottom of the hand wheel is in abutting press fit with the edge of the cover body.

Optionally, a lifting structure is further arranged on the cover body.

Optionally, the lifting structure includes:

the screw rod is arranged at the top of the cover body;

one end of the connecting rod is sleeved on the screw rod, and the other end of the connecting rod is fixedly arranged on the tank body;

the rotating disc is sleeved on the screw rod and is in threaded connection with the screw rod, and the bottom of the rotating disc is in contact with the connecting rod.

The technical scheme of the utility model has the following advantages:

1. according to the backwashing filter provided by the utility model, the cover body at the top of the tank body is opened, the filter element is inserted into the slot, the sealing ring at the mounting end of the filter element is tightly attached to the inner wall of the mounting opening of the slot, so that the sealing between the filter element and the slot is realized, the influence on the filtering effect caused by the fact that feed liquid flows out without being filtered by the filter element in the filtering process is avoided, the mounting openings of the seal ring and the slot are both arranged into conical structures with large upper parts and small lower parts, the mounting is convenient, the width of the seal ring is larger, the seal ring can be prevented from being worn down to the inside of the backwashing filter after long-time use, and the use safety is ensured; the backwash filter provided by the utility model solves the problem that a sealing ring at the upper end of a filter element is easy to break in the prior art.

2. According to the backwash filter provided by the utility model, the limiting protrusion card on the filter element is connected into the limiting clamping groove on the slot, and the filter element is fixed in the slot, so that the influence of loosening of the filter element in the filtering process on the filtering effect is avoided.

3. According to the backwash filter provided by the utility model, the special tool is inserted into the operation hole on the extension edge, so that the filter element is convenient to rotate, and when the filter element is installed, the limiting protrusion is aligned to the limiting clamping groove and is rotationally clamped in, so that the limiting fixation of the filter element is realized; when the filter element is disassembled, the filter element is rotated, so that the limiting protrusion slides out of the limiting clamping groove, and the filter element is extracted.

4. According to the back flushing filter provided by the utility model, feed liquid enters from the feed inlet of the tank body, flows out from the discharge outlet after being filtered by the filter element, so that the filtering process of feeding and discharging the feed liquid in the tank body is realized, when flushing is needed, the control device controls the closing of the regulating valves of the feed inlet and the discharge outlet, the regulating valves of the flushing liquid inlet 12 and the sewage outlet are opened, back flushing liquid enters from the top of the tank body, and sewage flows out from the sewage outlet at the bottom of the tank body, so that the back flushing of the filter element is realized.

5. According to the backwash filter provided by the utility model, the cylinder is controlled by the control device to drive the valve plate to rotate, when the driving rod of the cylinder drives the valve plate to be parallel to the fixed ring, the regulating valve is closed, and when the valve plate is vertical to the fixed ring, the regulating valve is opened.

6. According to the backwash filter provided by the utility model, the first trigger rod and the second trigger rod rotate along with the driving rod, when the regulating valve is opened, the tail end of the first trigger rod is close to the first sensor, and the first sensor feeds a signal back to the control device to prompt that the regulating valve is in an opened state; when the regulating valve is closed, the tail end of the second sensor is close to the second sensor, the second sensor feeds signals back to the control device, the regulating valve is prompted to be in a closed state, and whether the regulating valve is in a normal working state can be timely found.

7. According to the backwash filter provided by the utility model, the cover body is locked through the locking device at the top of the tank body, so that the cover body covers the top of the tank body in the filtering process, the use safety is ensured, and foreign matters can be prevented from entering the tank body.

8. When the locking device is locked, the screw rod is rotated to be in a vertical state, the hand wheel is screwed down, so that the hand wheel moves downwards along the screw rod, and the bottom of the hand wheel is used for pressing and locking the edge of the cover body; when the locking device is unlocked, the hand wheel is unscrewed, so that the hand wheel moves upwards along the screw rod, the bottom of the hand wheel is released from pressing the edge of the cover body, and the screw rod rotates towards the direction close to the tank body, so that the cover body is conveniently opened.

9. According to the backwashing filter provided by the utility model, through the upgrading structure on the cover body, the cover body can move upwards or downwards, so that the opening and sealing states of the cover body are realized.

10. According to the backwashing filter provided by the utility model, the bottom of the rotating disc is contacted with the connecting rod, the rotating disc is rotated to drive the screw rod to rotate, and the cover body is driven to move upwards or downwards along with the relative movement between the screw rod and the rotating disc.

Drawings

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

FIG. 1 is a schematic illustration of one implementation of a backwash filter provided in an example of the present utility model;

FIG. 2 is a schematic top view of the tank of FIG. 1;

FIG. 3 is a schematic view of the cartridge of FIG. 1;

FIG. 4 is a schematic illustration of the regulator valve of FIG. 1;

fig. 5 is a schematic view of the locking device of fig. 1.

Reference numerals illustrate:

1. a tank body; 2. a cover body; 3. a slot; 4. a filter element; 5. a seal ring; 6. a limit protrusion; 7. a limit clamping groove; 8. an extension edge; 9. a discharge port; 10. a feed inlet; 11. a sewage outlet; 12. a rinse inlet; 13. a regulating valve; 14. a valve body; 15. a fixing ring; 16. a valve plate; 17. a cylinder; 18. a driving rod; 19. a fixed rod; 20. a first trigger lever; 21. a second trigger lever; 22. a first inductor; 23. a second inductor; 24. a locking device; 25. a screw; 26. a hand wheel; 27. a screw rod; 28. a connecting rod; 29. and (5) rotating the disc.

Detailed Description

The following description of the embodiments of the present utility model will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the utility model are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In addition, the technical features of the different embodiments of the present utility model described below may be combined with each other as long as they do not collide with each other.

The embodiment provides a backwashing filter capable of prolonging the service life of a sealing ring 5, which is used for filtering feed liquid.

As shown in fig. 1-3, a specific implementation manner of a backwash filter provided in this embodiment includes: the novel filter comprises a tank body 1 and a filter element 4, wherein an opening is formed in the top of the tank body 1, a cover body 2 is arranged at the opening, a plurality of slots 3 are formed in the tank body 1, and a mounting opening at the upper end of each slot 3 is in a tapered structure from top to bottom; the filter element 4 is inserted in the slot 3, a sealing ring 5 is sleeved at the installation end of the filter element 4, the outer diameter of the sealing ring 5 is gradually reduced from top to bottom, and the outer surface of the sealing ring 5 is tightly attached to the inner wall of the installation opening of the slot 3.

When the filter is used, the cover body 2 at the top of the tank body 1 is opened, the filter element 4 is inserted into the slot 3, the sealing between the filter element 4 and the slot 3 is realized by tightly attaching the sealing ring 5 at the mounting end of the filter element 4 to the inner wall of the mounting opening of the slot 3, the influence on the filtering effect caused by the fact that feed liquid flows out without being filtered by the filter element 4 in the filtering process is avoided, the mounting openings of the sealing ring 5 and the slot 3 are both arranged into conical structures with large upper parts and small lower parts, the installation is convenient, the width of the sealing ring 5 is larger, the sealing ring 5 can be prevented from being worn down to the inside of a back flushing filter after long-time use, and the use safety is ensured; the backwash filter provided by the embodiment solves the problem that a sealing ring 5 at the upper end of a filter element 4 is easy to break in the prior art.

As shown in fig. 2 and 3, in the backwash filter provided in this embodiment, the mounting end of the filter element 4 is uniformly provided with a limiting protrusion 6 extending radially outwards, and the mounting opening of the slot 3 is provided with a limiting clamping groove 7 engaged with the limiting protrusion 6. When the filter is used, the limiting protrusion 6 on the filter element 4 is clamped into the limiting clamping groove 7 on the slot 3, the filter element 4 is fixed in the slot 3, and the influence on the filtering effect caused by loosening of the filter element 4 in the filtering process is avoided. In addition, as an alternative embodiment, the top ends of the filter element 4 and the slot 3 may be in threaded connection or other structures that can realize limiting fixation of the filter element 4.

As shown in fig. 3, in the backwash filter provided in this embodiment, the fixed end of the filter element 4 is further provided with an extending edge 8 extending upward, and an operation hole is provided on the extending edge 8. When the filter element 4 is used, the filter element 4 is conveniently rotated by inserting a special tool into the operation hole on the extension edge 8, and when the filter element 4 is installed, the limiting protrusion 6 is aligned with the limiting clamping groove 7 and is rotationally clamped in, so that the limiting fixation of the filter element 4 is realized; when the filter element 4 is disassembled, the filter element 4 is rotated, so that the limiting protrusion 6 slides out of the limiting clamping groove 7, and the filter element 4 is extracted. In addition, as an alternative embodiment, the extension edge 8 may be omitted, or a handle may be provided at the top of the filter element 4.

As shown in fig. 1, in the backwash filter provided in this embodiment, the tank body 1 is provided with a discharge port 9, a feed port 10 and a drain port 11 from top to bottom in sequence, the cover body 2 is provided with a rinse liquid inlet 12, and the pipelines of the drain port 11, the feed port 10, the discharge port 9 and the rinse liquid inlet 12 are all provided with a regulating valve 13, and the regulating valve 13 is electrically connected with a control device. When the filter is used, feed liquid enters from a feed inlet 10 of the tank body 1, flows out from a discharge outlet 9 after being filtered by the filter element 4, so that the filtration process of feeding the feed liquid into the tank body 1 from bottom to top is realized, when flushing is needed, the control device controls the feed inlet 10 and the regulating valve 13 of the discharge outlet 9 to be closed, the flushing liquid inlet 12 and the regulating valve 13 of the sewage drain outlet 11 are opened, the flushing liquid enters from the top of the tank body 1, sewage flows out from the sewage drain outlet 11 at the bottom of the tank body 1, and the reverse flushing of the filter element 4 is realized.

As shown in fig. 1 and 4, in the backwash filter provided in this embodiment, the adjusting valve 13 includes: a valve body 14 and a cylinder 17; the valve body 14 is arranged in the pipelines of the sewage outlet 11, the feeding hole 10, the discharging hole 9 and the flushing liquid inlet 12, and is provided with a fixed ring 15 and a valve plate 16 which can be opened and closed in a rotating way; the cylinder 17 is arranged outside the pipelines of the sewage outlet 11, the feeding hole 10, the discharging hole 9 and the flushing liquid inlet 12, the cylinder 17 is electrically connected with the control device, the cylinder 17 is connected with the fixed ring 15 through the fixed rod 19, the driving rod 18 of the cylinder 17 penetrates through the fixed ring 15 to be connected with the valve plate 16, and the valve plate 16 is driven to rotate through the driving rod 18. When the valve plate 16 is used, the cylinder 17 is controlled by the control device to drive the valve plate 16 to rotate, when the driving rod 18 of the cylinder 17 drives the valve plate 16 to be parallel to the fixed ring 15, the regulating valve 13 is closed, and when the valve plate 16 is perpendicular to the fixed ring 15, the regulating valve 13 is opened. In addition, as an alternative embodiment, the cylinder 17 may be omitted, or an electric driving device may be provided.

As shown in fig. 4, in the backwash filter provided in this embodiment, a first trigger rod 20 and a second trigger rod 21 are fixedly disposed on the driving rod 18, the first trigger rod 20 is disposed parallel to a plane where the fixing ring 15 is located, the first trigger rod 20 and the first trigger rod 20 are disposed vertically, a first sensor 22 and a second sensor 23 are disposed on the fixing rod 19, the first sensor 22 and the second sensor 23 are electrically connected with the control device, when the valve plate 16 is opened, an end of the first trigger rod 20 is close to the first sensor 22, and when the valve plate 16 is closed, an end of the second trigger rod 21 is close to the second sensor 23. When in use, the first trigger lever 20 and the second trigger lever 21 rotate along with the driving lever 18, and when the regulating valve 13 is opened, the tail end of the first trigger lever 20 approaches the first sensor 22, and the first sensor 22 feeds back a signal to the control device to prompt the regulating valve 13 to be in an opened state; when the regulating valve 13 is closed, the tail end of the second inductor 23 is close to the second inductor 23, and the second inductor 23 feeds back a signal to the control device to prompt that the regulating valve 13 is in a closed state, so that whether the regulating valve 13 is in a normal working state can be timely found.

As shown in fig. 1 and 2, in the backwash filter provided in this embodiment, a plurality of locking devices 24 are uniformly disposed on the top of the tank 1 along the circumferential direction, and the cover 2 is locked by the locking devices 24. When in use, the locking device 24 is arranged at the top of the tank body 1 to lock the cover body 2, so that the cover body 2 covers the top of the tank body 1 in the filtering process, the use safety is ensured, and foreign matters can be prevented from entering the tank body 1. In addition, as an alternative embodiment, the locking device 24 may also be provided on the cover 2.

As shown in fig. 1, 2, and 5, in the backwash filter provided in this embodiment, the locking device 24 includes: the screw rod 25 and the hand wheel 26, wherein the screw rod 25 is rotatably arranged on the outer side of the top of the tank body 1; the hand wheel 26 is sleeved on the screw rod 25, the hand wheel 26 is in threaded connection with the screw rod 25, and the bottom of the hand wheel 26 is in abutting press fit with the edge of the cover body 2. When the locking device 24 is locked, the screw 25 is rotated to be in a vertical state, the hand wheel 26 is screwed down, so that the hand wheel 26 moves downwards along the screw 25, and the bottom of the hand wheel 26 performs pressing locking on the edge of the cover body 2; when the locking device 24 is unlocked, the hand wheel 26 is unscrewed, so that the hand wheel 26 moves upwards along the screw rod 25, the bottom of the hand wheel 26 releases the pressing of the edge of the cover body 2, and the screw rod 25 rotates towards the direction close to the tank body 1, so that the cover body 2 is conveniently opened. In addition, as an alternative embodiment, the hand wheel 26 may be replaced with other structures such as a hanging ring or a deflector rod.

As shown in fig. 1, in the backwash filter provided in this embodiment, a lifting structure is further disposed on the cover 2. When in use, the cover body 2 can move upwards or downwards through the upgrading structure on the cover body 2, so that the cover body 2 is in an opened or sealed state. In addition, as an alternative embodiment, the cover 2 may be hinged to the can 1, so that the cover 2 may be turned over.

As shown in fig. 1, in the backwash filter provided in this embodiment, the lifting structure includes: a screw rod 27, a connecting rod 28 and a rotating disc 29; the screw rod 27 is arranged at the top of the cover body 2; one end of the connecting rod 28 is sleeved on the screw rod 27, and the other end is fixedly arranged on the tank body 1; the rotating disc 29 is sleeved on the screw rod 27 and is in threaded connection with the screw rod 27, and the bottom of the rotating disc 29 is in contact with the connecting rod 28. When in use, the bottom of the rotary disk 29 is contacted with the connecting rod 28, and the rotary disk 29 is rotated, so that the screw rod 27 is rotated, and the cover body 2 is driven to move upwards or downwards along with the relative movement between the screw rod 27 and the rotary disk 29. In addition, as an alternative embodiment, the screw rod 27 and the rotating disk 29 may be omitted, and an electric telescopic rod, a pneumatic telescopic rod or other driving device capable of moving up and down is provided on the connecting rod 28.

Application method

As shown in fig. 1 to 5, in the back flushing filter provided in this embodiment, when the back flushing filter is used, the filter element 4 is inserted into the slot 3, and passes through the operation hole on the extension edge 8 by a special tool, the filter element 4 is rotated to enable the limit protrusion 6 to be clamped into the limit clamping groove 7, the rotating disc 29 is rotated to enable the tank body 1 to move downwards to be in contact with the tank body 1, the hand wheel 26 is rotated to enable the locking device to lock the cover body 2, and when the filter element 4 needs to be disassembled and washed, the hand wheel 26 is rotated to release the locking device from locking the cover body 2, the rotating disc 29 is rotated to enable the cover body 2 to move upwards, and passes through the operation hole on the extension edge 8 by a special tool, the filter element 4 is rotated to be lifted upwards, and the filter element 4 is replaced or manually flushed.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present utility model.

Claims (10)

1. A backflushing filter, comprising:

the novel water tank comprises a tank body (1), wherein an opening is formed in the top of the tank body (1), a cover body (2) is arranged at the opening, a plurality of slots (3) are formed in the tank body (1), and a mounting opening at the upper end of each slot (3) is in a tapered structure from top to bottom;

the filter element (4) is inserted in the slot (3), a sealing ring (5) is sleeved at the installation end of the filter element (4), the outer diameter of the sealing ring (5) is gradually reduced from top to bottom, and the outer surface of the sealing ring (5) is tightly attached to the inner wall of the installation opening of the slot (3).

2. The backwash filter according to claim 1, wherein the mounting end of the filter element (4) is uniformly provided with a limiting protrusion (6) extending outwards in a radial direction, and the mounting opening of the slot (3) is provided with a limiting clamping groove (7) in clamping fit with the limiting protrusion (6).

3. A backflushing filter according to claim 1, characterized in that the fixed end of the filter cartridge (4) is further provided with an upwardly extending extension edge (8), the extension edge (8) being provided with an operating aperture.

4. The backwash filter according to claim 1, wherein the tank body (1) is provided with a discharge port (9), a feed port (10) and a drain port (11) from top to bottom in sequence, the cover body (2) is provided with a flushing fluid inlet (12), and the drain port (11), the feed port (10), the discharge port (9) and the flushing fluid inlet (12) are all provided with regulating valves (13) on the pipelines, and the regulating valves (13) are electrically connected with a control device.

5. A backwash filter according to claim 4, wherein the regulating valve (13) comprises:

the valve body (14) is arranged in pipelines of the sewage outlet (11), the feed inlet (10), the discharge outlet (9) and the flushing fluid inlet (12) and is provided with a fixed ring (15) and a valve plate (16) which can be opened and closed in a rotating way;

the cylinder (17) is arranged outside pipelines of the sewage outlet (11), the feeding hole (10), the discharging hole (9) and the flushing fluid inlet (12), the cylinder (17) is electrically connected with the control device, the cylinder (17) is connected with the fixed ring (15) through the fixed rod (19), and a driving rod (18) of the cylinder (17) penetrates through the fixed ring (15) to be connected with the valve plate (16) and drives the valve plate (16) to rotate through the driving rod (18).

6. The backwash filter according to claim 5, wherein a first trigger lever (20) and a second trigger lever (21) are fixedly arranged on the driving lever (18), the first trigger lever (20) is arranged parallel to a plane where the fixing ring (15) is located, the first trigger lever (20) and the first trigger lever (20) are vertically arranged, a first sensor (22) and a second sensor (23) are arranged on the fixing lever (19), the first sensor (22) and the second sensor (23) are electrically connected with the control device, when the valve plate (16) is opened, the tail end of the first trigger lever (20) is close to the first sensor (22), and when the valve plate (16) is closed, the tail end of the second trigger lever (21) is close to the second sensor (23).

7. The backwash filter according to any one of claims 1-6, wherein a plurality of locking devices (24) are evenly arranged on the top of the tank (1) along the circumferential direction, and the cover (2) is locked by the locking devices (24).

8. A backwash filter according to claim 7, wherein the locking means (24) comprises:

the screw rod (25) is rotatably arranged on the outer side of the top of the tank body (1);

the hand wheel (26) is sleeved on the screw rod (25), the hand wheel (26) is in threaded connection with the screw rod (25), and the bottom of the hand wheel (26) is in abutting press fit with the edge of the cover body (2).

9. The backwash filter according to claim 7, wherein the lid (2) is further provided with a lifting structure.

10. The backwash filter of claim 9 wherein the lifting structure comprises:

the screw rod (27) is arranged at the top of the cover body (2);

one end of the connecting rod (28) is sleeved on the screw rod (27), and the other end of the connecting rod is fixedly arranged on the tank body (1);

the rotating disc (29) is sleeved on the screw rod (27) and is in threaded connection with the screw rod (27), and the bottom of the rotating disc (29) is in contact with the connecting rod (28).