CN217829161U

CN217829161U - Leading filter equipment of water heater and water heater

Info

Publication number: CN217829161U
Application number: CN202221059329.1U
Authority: CN
Inventors: 卢楚鹏; 董雄华; 伍家雄
Original assignee: Guangdong Vanward New Electric Co Ltd
Current assignee: Guangdong Vanward New Electric Co Ltd
Priority date: 2022-04-29
Filing date: 2022-04-29
Publication date: 2022-11-18
Anticipated expiration: 2032-04-29

Abstract

The utility model belongs to the technical field of household appliances and filtration, and discloses a water heater pre-filtering device and a water heater, wherein the water heater pre-filtering device comprises a main body pipeline and a filtering component, the main body pipeline comprises a water inlet end, a water outlet end and an installation part, a water flow channel is formed between the water inlet end and the water outlet end, the installation part is provided with an installation channel communicated with the water flow channel, and the installation channel is provided with an installation port; the filter assembly comprises a filter screen and a sealing main body, the filter screen is connected to one end of the sealing main body, one end of the sealing main body is sequentially inserted into the mounting opening and the mounting passage, the mounting opening is blocked, the sealing main body is clamped and fixed with the mounting portion, and the filter screen is located in the water flow passage to filter impurities in water. The utility model realizes the independent disassembly and assembly of the filtering component, has simple disassembly and assembly process and improves the disassembly and assembly efficiency; through setting up seal assembly and installation department joint, need not just can realize filtering component's fixed mounting and dismantlement with the help of the instrument, be convenient for realize quick assembly disassembly.

Description

Leading filter equipment of water heater and water heater

Technical Field

The utility model relates to a domestic appliance and filtration technical field especially relate to a leading filter equipment of water heater and water heater.

Background

In general water route or water piping structure, set up filtration in order to filter aquatic impurity usually between water pipe and valve, when carrying out filtration and unpick and wash, need dismantle the water pipe earlier, take off filtration again, unpick and wash the process complicacy, it is inefficient, and filtration is restricted to the water pipe aperture, therefore filter area is little, and filtration is blockked up by impurity easily.

In order to solve the technical problem, the detachable connection between the filtering structure and the valve body is realized by arranging the filtering structure on the valve body in the prior art, so that the water pipe does not need to be detached when the filtering structure is detached, and the detaching and washing process of the filtering structure can be simplified. The problem that exists is that the detachable installation of filtration all adopts threaded connection, generally need be with the help of the instrument at the dismouting in-process, and the structure is complicated, influences dismantlement efficiency. For the inlet tube in the water heater, because need frequently unpick and wash filtration, consequently the requirement of dismouting efficiency is higher.

SUMMERY OF THE UTILITY MODEL

One of the technical problems solved by the present invention is to provide a front filter device for water heater, which effectively solves the problem of low efficiency of disassembly and assembly by means of tools.

The second technical problem solved by the present invention is to provide a water heater, which can effectively solve the problem of low efficiency of the assembly and disassembly of the filter assembly between the water heater and the water inlet pipe by means of tools.

The first technical problem is solved by the following technical scheme:

a water heater pre-filter apparatus comprising:

the main body pipeline comprises a water inlet end, a water outlet end and a mounting part, a water flow channel is formed between the water inlet end and the water outlet end, the mounting part is provided with a mounting channel communicated with the water flow channel, and the mounting channel is provided with a mounting port;

the filter assembly, filter assembly includes filter screen and sealed main part, the filter screen is connected the one end of sealed main part, the one end of sealed main part is inserted in order and is located the installing port with the installation passageway, and the shutoff the installing port, sealed main part with the installation department joint is fixed, the filter screen is located impurity in order to filter the aquatic in the rivers passageway.

In one embodiment, the water heater pre-filtering device further comprises a clamping pin, and one end of the clamping pin penetrates into the outer wall of the mounting part and the mounting channel in sequence and is clamped with the sealing main body.

In one embodiment, the bayonet lock is an elastic part with an outer splayed structure, and two ends of the bayonet lock respectively penetrate through the outer wall of the installation part and the installation channel in sequence and are clamped with two sides of the sealing main body.

In one embodiment, two sides of the sealing main body are respectively provided with a limiting groove, and the limiting grooves are positioned in the mounting channel;

the outer peripheral wall of the mounting part is provided with a first through hole and a second through hole, and the first through hole and the second through hole are respectively communicated with two ends of the limiting groove;

the two ends of the clamping pins sequentially penetrate through the first through holes, the limiting grooves and the second through holes to be clamped and fixed with the sealing main body.

In one embodiment, the peripheral wall of the sealing main body is provided with an annular clamping groove, and a sealing ring is sleeved in the annular clamping groove to seal a gap between the sealing main body and the mounting part.

In one embodiment, the mounting portion and the seal body each have an elliptical or oblong cross-section.

In one embodiment, the inner wall of the installation channel is provided with a positioning groove, and the edge of the filter screen can be inserted into the positioning groove to be installed in a matched mode.

In one embodiment, the filter assembly further comprises a handle, and the handle and the filter screen are respectively arranged at two opposite ends of the sealing main body.

In one embodiment, the bayonet lock is formed by bending a round rod piece made of metal, and the diameter of the round rod piece is not less than 2mm.

The second technical problem is solved by the following technical solutions:

the water heater comprises the water heater front-mounted filter device, and the water heater front-mounted filter device is arranged between a water heater body and a water inlet pipe.

Leading filter equipment of water heater, compare with the background art, the beneficial effect who has is:

the utility model discloses a leading filter equipment of water heater through set up the installation passageway at the installation department of main part pipeline, is convenient for realize the independent dismouting of filter assembly, and the dismouting process is simple, improves dismouting efficiency; through setting up seal assembly and installation department joint, need not just can realize filter assembly's fixed mounting and dismantlement with the help of the instrument, be convenient for realize quick assembly disassembly, sealed for the threaded connection among the prior art, dismouting efficiency improves greatly.

Water heater, compare with the background art, the beneficial effect who has does:

set up leading filter equipment of water heater between water heater body and inlet tube, with filter assembly's sealed main part and installation department joint, realize filter assembly's quick assembly disassembly simplifies the dismouting process, need not realize dismantling with the help of the instrument, dismantlement efficiency improves.

Drawings

Fig. 1 is a schematic view of the overall structure of a pre-filtering device of a water heater according to the present invention;

fig. 2 is a schematic cross-sectional view of a pre-filtering device of a water heater according to the present invention;

fig. 3 is an exploded schematic view of a pre-filter of a water heater according to the present invention;

FIG. 4 is a schematic structural view of a bayonet lock of a pre-filter of a water heater according to the present invention;

fig. 5 is a schematic structural diagram of a filter assembly in a pre-filter of a water heater according to the present invention;

fig. 6 is a schematic structural view of a main pipeline in the pre-filter of a water heater of the present invention.

Description of the reference symbols:

1. a main body pipeline; 11. a water inlet end; 12. a water outlet end; 13. an installation part; 131. a first through hole; 132. a second through hole; 14. installing a channel; 141. positioning a groove; 15. an installation port;

2. a filter assembly; 21. filtering with a screen; 211. a frame; 22. a sealing body; 221. a limiting groove; 222. an annular clamp groove; 23. a handle;

3. a bayonet lock; 4. and (5) sealing rings.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless otherwise explicitly specified or limited, the terms "connected", "connected" and "fixed" are to be construed broadly, e.g., as being fixedly connected, detachably connected, or integrated; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature "on," "above" and "over" the second feature may include the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is at a higher level than the second feature. "beneath," "under" and "beneath" a first feature includes the first feature being directly beneath and obliquely beneath the second feature, or simply indicating that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", and the like are used based on the orientations and positional relationships shown in the drawings, and are only for convenience of description and simplification of operation, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

The utility model discloses at first provide a leading filter equipment of water heater, set up between water heater body and inlet tube for filter the impurity of aquatic, have and dismantle convenient and fast, need not dismantle the inlet tube, and have the big advantage of filtration area of contact.

As shown in fig. 1-3, the water heater pre-filtering device includes a main pipeline 1 and a filtering component 2, the main pipeline 1 is of a three-way structure, the main pipeline 1 includes a water inlet end 11, a water outlet end 12 and an installation part 13, the water inlet end 11 and the water outlet end 12 are respectively used for connecting the water heater body and the water inlet pipe to form a water flow channel, the installation part 13 is provided with an installation channel 14 communicated with the water flow channel, and the installation channel is provided with an installation port 15; the filter assembly 2 comprises a filter screen 21 and a sealing main body 22, the filter screen 21 is connected to one end of the sealing main body 22, one end of the sealing main body 22 is sequentially inserted into the mounting port 15 and the mounting channel 14 and blocks the mounting port 15, and the filter screen 21 is positioned in a water flow channel between the water inlet end 11 and the water outlet end 12 to filter impurities in water; the seal body 22 is fixed to the mounting portion 13 by snap-fitting.

Sealed for threaded connection among the prior art, to seal main part 22 in this embodiment and fix with 13 joints of installation department, have the swift advantage of dismouting, do not need supplementary screw thread extracting tool, dismouting efficiency improves greatly, is applicable to and needs often to dismantle and carries out abluent use operating mode. In this embodiment, install the passageway 14 with the installation of rivers passageway intercommunication at main part pipeline 1's installation department 13 setting, realize filtering component 2 and main part pipeline 1's independent dismouting, need not dismantle inlet tube or main part pipeline 1 during the dismantlement, the dismouting process is simple, improves dismouting efficiency.

It should be noted that, in this embodiment, the water inlet end 11 and the water outlet end 12 of the main pipeline 1 are respectively provided with a threaded structure for detachably connecting the water heater body and the water inlet pipe, the threaded structure may be an external thread or an internal thread, and the pipe section between the water inlet end 11 and the water outlet end 12 is generally a straight pipe circular pipe section to match the unobstructed and sealed connection of the water flow between the water heater body and the water inlet pipe. In this embodiment, the installation channel 14 penetrates through or between the water inlet end 11 and the water outlet end 12 to form the installation channel 14 transversely disposed between the water inlet end 11 and the water outlet end 12, when the sealing body 22 and the filter screen 21 extend from the opening end of the installation channel 14 to the inside of the main pipeline 1, the edge of the filter screen 21 can be abutted against the inner wall of the installation channel 14 to filter impurities in the water flow channel flowing through the main pipeline 1, when the front end of the filter screen 21 is abutted against the inner wall of the end portion of the installation portion 13, the filter screen 21 is just located at a cross section of the water flow channel between the water inlet end 11 and the water outlet end 12, and the sealing body 22 seals the installation port 15 and is in sealing clamping connection with the installation portion 13. Therefore, the water leakage condition possibly caused by the looseness of the threaded connection is avoided by the clamping mode, and the clamping mode is completed in the process of disassembling and assembling the filter screen assembly 2, so that the disassembling and assembling efficiency is greatly improved.

In one embodiment, the water heater pre-filter device further comprises a clamping pin 3, and one end of the clamping pin 3 penetrates into the outer wall of the mounting part 13 and the mounting channel 14 in sequence and is clamped with the sealing main body 22.

As shown in fig. 1, the bayonet 3 penetrates through the pipe wall of the mounting part 13 and the mounting channel 14 from top to bottom, and the sealing main body 22 is clamped in the mounting channel 14 to prevent the sealing main body 22 from rotating and moving so as to ensure the position stability of the filter screen 21 during filtering.

In one embodiment, the locking pin 3 is an elastic member with an external splayed structure, and two ends of the locking pin 3 respectively penetrate into the outer wall of the mounting part 13 and the mounting channel 14 in sequence and are clamped with two sides of the sealing main body 22.

As shown in fig. 4, bayonet lock 3's major structure is the U type structure of flaring, wholly be outer eight characters structure, accessible elastic component bending type becomes, the maximum distance between bayonet lock 3's the both ends is greater than the width of sealed main part 22, bayonet lock 3's both ends can wear to establish respectively and press from both sides tight in the both sides of sealed main part 22, with the spacing joint of symmetry is provided to the both sides to sealed main part 22, outer eight characters structure can prevent that bayonet lock 3 from taking place not hard uply in the installation use, bayonet lock 3 wears to establish the outer wall of installation department 13, installation passageway 14 and sealed main part 22 back, because tension acts on, the outside at bayonet lock 3 both ends can end and support in the outer wall of installation department 13 in order to increase frictional force, realize the locking effect that moves.

In one embodiment, the two sides of the sealing body 22 are respectively provided with a limiting groove 221, and the limiting grooves 221 are positioned in the installation channel 14; a first through hole 131 and a second through hole 132 are formed in the outer peripheral wall of the mounting portion 13, and the first through hole 131 and the second through hole 132 are respectively communicated with the upper end and the lower end of the limiting groove 221; the two ends of the bayonet 3 are respectively and sequentially penetrated through the first through hole 131, the limiting groove 221 and the second through hole 132 to axially limit and clamp and fix the sealing main body 22.

As shown in fig. 5, the sealing body 22 is provided with a limiting groove 221 on both sides, and the depth and width of the limiting groove 221 are preferably equal to the dimensions of both ends of the bayonet 3, so as to be fitted with both ends of the bayonet 3, and to reduce the gap between both ends of the bayonet 3 and the limiting groove 221 as much as possible, so as to improve the sealing and connecting positioning accuracy. The length of the limiting groove 221 along the outer peripheral wall of the sealing main body 22 needs to satisfy the requirement of the outer splayed structure at the two ends of the bayonet pin 3, so that one end of the limiting groove 221 is located at the top of the sealing main body 22, and the other end at least penetrates through the two sides of the sealing main body 22. In some embodiments, two limiting grooves 221 are provided, and are symmetrically disposed on two sides of the sealing body 22, and in other embodiments, one limiting groove 221 is provided, that is, the limiting groove 221 is an open-loop or closed-loop groove provided on the sealing body 22, and is disposed around the outer peripheral wall of the sealing body 22, and the processing is simple.

In one of the embodiments, four through holes are arranged on the mounting portion 13, two top symmetry are arranged as first through holes 131, two bottom symmetry are arranged as second through holes 132, the left and right sides are divided into two groups, the first through holes 131 above and the second through holes 132 below are respectively communicated with one side of the limiting groove 221, two ends of the bayonet pins 3 are respectively penetrated in the first through holes 131 and the second through holes 132 on the same side, penetrating from top to bottom is formed, the elastic tension of the outer splayed structure of the bayonet pins 3 is easily and fully utilized, the fixing and sealing main body 22 is tensioned, two ends of the bayonet pins 3 penetrate through the second through holes 132 on the bottom of the mounting portion 13, and sufficient extension sections are arranged outside the mounting portion 13, so that looseness and slippage of the bayonet pins 3 can be prevented, and mounting reliability is improved. As shown in FIG. 2, when the latch 3 is mounted, the top of the latch 3 abuts against the top of the mounting portion 13 to facilitate mounting and positioning. It will be appreciated that the top structure of the bayonet 3 preferably conforms to the shape and size of the top of the mounting portion 13 to achieve the abutting and abutting locating effect.

In one embodiment, the outer circumferential wall of the sealing body 22 is provided with a ring-shaped groove 222, and a sealing ring 4 is sleeved in the ring-shaped groove 222 to seal a gap between the sealing body 22 and the mounting portion 13.

As shown in fig. 5, the outer peripheral wall of the sealing body 22 is provided with at least two spaced ring-shaped slots 222, which are matched with the two sealing rings 4 in fig. 3, the two sealing rings 4 are respectively sleeved in the two ring-shaped slots 222, and when the sealing body 22 is installed, the sealing rings 4 can be clamped between the sealing body 22 and the inner wall of the installation part 13 to realize the sealing installation of the channel 14 and the installation. The number of ring slots 222 and the number of sealing rings 4 in each ring slot 222 can be selectively set according to the sealing requirements and the related lengths of the sealing main body 22 and the installation channel 14, generally, the number of ring slots 222 is not less than two, and at least one sealing ring 4 is arranged in each ring slot 222, so that a better sealing effect is achieved.

In one embodiment, the seal body 22 and the mounting portion 13 are each oval or oblong in cross-section.

As shown in fig. 3, the elliptical or oblong cross section is convenient for the installation and positioning of the sealing main body 22 and the installation channel 14, the filter screen 21 of the filter assembly 2 moves along the long axis direction for disassembly and assembly, and the rotation does not occur during the disassembly and assembly process, thereby improving the disassembly and assembly efficiency. The oval or oblong cross-section facilitates providing a minimum installation space perpendicular to the water inlet end 11 and the water outlet end 12, which in turn facilitates reducing the structural size and cost of the overall body conduit 1. Accordingly, the sealing ring 4 is oval or oblong so as to fit within an oval or oblong annular groove 222 on the outer peripheral wall of the sealing body 22.

In one embodiment, the inner wall of the installation channel 14 is provided with a positioning groove 141, and the edge of the filter screen 21 can be inserted into the positioning groove 141 to be installed in a matching manner.

With reference to fig. 6, the groove width and the groove depth of the positioning groove 141 are matched with the edge of the filter screen 21 so as to facilitate installation, as shown in fig. 5, the edge of the filter screen 21 is provided with a frame 211 to enhance the installation strength of the filter screen 21 and the connection strength between the filter screen 21 and the sealing main body 22, in the preferred embodiment, the frame 211 and the sealing main body 22 are of an integral structure so as to facilitate the whole assembly and disassembly of the filter screen assembly 2 and facilitate cleaning. In order to facilitate the installation, positioning and sealing of the filter screen 21, the other end of the installation channel 14, which is opposite to the installation opening 15, is a flat-bottom end surface, positioning grooves 141 are formed in both the flat-bottom end surface and the two side walls of the installation channel 14, and the installation channel and the filter screen 21 are installed in a three-surface positioning manner. Preferably, the frame 211 is provided with an elastic sealing strip to be sealingly mounted with the positioning groove 141.

In one embodiment, the filter assembly 2 further comprises a pull handle 23, and the pull handle 23 and the filter screen 21 are respectively disposed at two opposite ends of the sealing body 22.

As shown in fig. 2 and 5, the handle 23 is provided on the sealing body 22 and opposite to the filter net 21, and the handle 23 facilitates the assembly and disassembly of the filter assembly 2 by hand.

In one embodiment, the retaining groove 221 is disposed between the ring slot 222 and the pull 23.

As shown in fig. 5, in some embodiments, the stopper groove 221 may be formed in a ring shape having the same structure as the ring-shaped retaining groove 222 for easy processing without affecting the mounting and positioning of the retaining pins 3. When the sealing ring 4 is installed, the sealing ring 4 is arranged in at least two annular clamping grooves 222 close to the filter screen 21, so that the sealing between the sealing main body 22 and the inner wall of the installation channel 14 is realized, and water leakage is prevented. The position of the limiting groove 221 corresponds to the position of the through hole 141 on the mounting channel 14, and the limiting groove 221 is arranged at one end far away from the filter screen 21, so that the bayonet 3 is conveniently connected with the sealing main body 22 at the mounting channel 14 after being blocked, and the bayonet 3 is prevented from contacting water.

In one embodiment, the bayonet 3 is formed by bending a round rod made of metal, and the diameter of the round rod is not less than 2mm.

As shown in fig. 3 and 4, when the bayonet 3 is a circular rod made of metal, the first through hole 131 and the second through hole 132 are circular holes, and the diameters of the first through hole 131 and the second through hole 132 are equal to the outer diameters of the two ends of the bayonet 3, so as to facilitate the insertion and installation. During installation, the two ends of the bayonet lock 3 are slightly forced to enable the opening of the bayonet lock 3 to be just inserted into the two first through holes 131 at the top, the force is continuously applied until the bayonet lock 3 penetrates through the installation channel 14, the bayonet lock 3 is released after the two second through holes 132 at the bottom are penetrated, after the bayonet lock 3 is continuously inserted downwards in place, the two ends of the bayonet lock 3 are tensioned on the hole walls of the four first through holes 131 and the four second through holes 132, meanwhile, the two end rods of the bayonet lock 3 are radially clamped in the limiting groove 221, and clamping and anti-loosening installation are achieved. It can be understood that bayonet 3 satisfies the elasticity demand to bayonet 3's both ends for metal material, and the diameter is generally not more than 3mm when selecting the round bar piece to be unlikely to too hard when being operated by the staff. Of course, the specific diameter is not limited to this embodiment, and other diameter data may be selected depending on the elasticity and rigidity of the material selected for the bayonet 3. The click 3 is not limited to a round bar, and may be an elastic member such as an elastic piece.

The utility model provides a water heater through set up the leading filter equipment of water heater between water heater body and inlet tube, is fixed with the sealed main part 22 of

filter component

2 and 13 joints of installation department, and bayonet lock 3 is the plug-in connection, has realized filter component 2's quick assembly disassembly, simplifies the dismouting process, need not realize dismantling with the help of the instrument, dismantles efficiency improvement.

In the detailed description of the embodiments, various technical features may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The details of the foregoing embodiments are merely representative of several embodiments of the present invention, which are described in more detail and detail, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the concept of the present invention, several variations and modifications can be made, which all fall within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A pre-filter device for a water heater, comprising:

the water flow pipeline comprises a main body pipeline (1), wherein the main body pipeline (1) comprises a water inlet end (11), a water outlet end (12) and a mounting part (13), a water flow channel is formed between the water inlet end (11) and the water outlet end (12), the mounting part (13) is provided with a mounting channel (14) communicated with the water flow channel, and the mounting channel (14) is provided with a mounting port (15);

filtering component (2), filtering component (2) include filter screen (21) and sealed main part (22), filter screen (21) are connected the one end of sealed main part (22), the one end of sealed main part (22) is inserted in order and is located installing port (15) with installation passageway (14), and the shutoff installing port (15), sealed main part (22) with installation department (13) joint is fixed, filter screen (21) are located in order to filter the impurity in the aquatic in the rivers passageway.

2. The pre-filtering device of the water heater as claimed in claim 1, further comprising a bayonet (3), wherein one end of the bayonet (3) penetrates into the outer wall of the mounting part (13) and the mounting channel (14) in sequence and is clamped with the sealing main body (22).

3. The front filtering device of the water heater according to claim 2, wherein the bayonet lock (3) is an elastic part with an outer splayed structure, and two ends of the bayonet lock (3) respectively penetrate into the outer wall of the mounting part (13) and the mounting channel (14) in sequence and are clamped with two sides of the sealing main body (22).

4. The pre-filtering device for the water heater according to the claim 3, characterized in that, the sealing main body (22) is provided with a limiting groove (221) on two sides, the limiting groove (221) is located in the installation channel (14);

a first through hole (131) and a second through hole (132) are formed in the outer peripheral wall of the mounting portion (13), and the first through hole (131) and the second through hole (132) are communicated with two ends of the limiting groove (221) respectively;

the both ends of bayonet lock (3) wear to establish respectively in proper order first through-hole (131) spacing groove (221) with second through-hole (132) are in order right sealed main part (22) joint is fixed.

5. The pre-filtering device for the water heater according to any one of the claims 1-4, characterized in that the outer peripheral wall of the sealing main body (22) is provided with an annular clamping groove (222), and a sealing ring (4) is sleeved in the annular clamping groove (222) to seal a gap between the sealing main body (22) and the mounting part (13).

6. Water heater pre-filter device according to any one of claims 1 to 4, characterised in that the cross-section of the mounting portion (13) and of the sealing body (22) is oval or oblong.

7. The pre-filtering device for the water heater according to any one of the claims 1 to 4, characterized in that the inner wall of the installation channel (14) is provided with a positioning groove (141), and the edge of the filter screen (21) can be inserted into the positioning groove (141) to be installed in a matching way.

8. The pre-filter device according to any of the claims 1 to 4, characterized in that the filter assembly (2) further comprises a pull handle (23), and the pull handle (23) and the filter screen (21) are respectively arranged at two opposite ends of the sealing main body (22).

9. The pre-filtering device of a water heater as claimed in any one of claims 2 to 4, wherein the bayonet lock (3) is formed by bending a round rod piece made of metal, and the diameter of the round rod piece is not less than 2mm.

10. A water heater, characterized in that: the water heater pre-filtering device comprises the water heater pre-filtering device as defined in any one of claims 1 to 9, and is arranged between a water heater body and a water inlet pipe.