CN219810051U - Anti-downdraft pipeline and gas water heater - Google Patents

Abstract

The utility model relates to an anti-backflow pipeline, which comprises a smoke exhaust pipe, a bracket arranged in the smoke exhaust pipe, and two anti-backflow plates arranged on the bracket, wherein the bracket comprises an annular frame, a cross beam arranged in the middle of the annular frame and two hinging seats arranged on the annular frame, and the two hinging seats are respectively positioned at two end sides of the cross beam; the anti-backflow plate is provided with an ear plate, the ear plate extends along the direction deviating from the support, the ear plates on the two anti-backflow plates are rotationally connected with the hinge seat through the same hinge shaft, the inner edge of the ear plate part protruding out of the anti-backflow plate is provided with a hinge hole for the hinge shaft to pass through, and the axis of the hinge hole is not intersected with the projection of the anti-backflow plate in the plane parallel to the anti-backflow plate. The utility model reduces the resistance in the smoke flowing process, so that the smoke of the gas water heater is smoother, and the combustion performance of the gas water heater is improved.

Description

Anti-downdraft pipeline and gas water heater

Technical Field

The utility model relates to the technical field of gas appliances, in particular to an anti-downdraft pipeline and a gas water heater.

Background

The exhaust pipeline of the gas water heater is generally provided with an anti-backflow device, the common anti-backflow device is designed by adopting double anti-backflow plates, a support is arranged in the smoke exhaust pipe, the two anti-backflow plates are hinged with the support through the same hinge shaft, and in order to improve the tightness, a cross beam is required to be arranged on the support so as to cover a gap between the two anti-backflow plates. When the water heater fan works, the discharged air flow pushes away the backflow preventing plate, so that the smoke exhaust pipe is in a passage state; when the fan does not work, the backflow prevention plate resets under the action of gravity, so that the smoke exhaust pipe is in a closed state, and cold air is prevented from flowing into the water heater in winter, and accumulated water in the heat exchanger pipe is prevented from icing and cracking the pipe fitting.

However, the splice seam formed after the two existing backflow prevention plates are spliced is not neat, for example, the width of a cross beam is required to be enlarged in the design mode to shield the splice seam, and larger resistance can be generated to the flow of smoke after the width of the cross beam is enlarged, so that the combustion performance of the water heater is affected.

Disclosure of Invention

The first technical problem to be solved by the utility model is to provide an anti-downdraft pipeline which effectively reduces the flow resistance of smoke so as to improve the combustion performance of the water heater.

The second technical problem to be solved by the utility model is to provide a gas water heater, which effectively reduces the flow resistance of smoke so as to improve the combustion performance of the water heater.

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

the anti-downdraft pipeline comprises a smoke exhaust pipe and a bracket arranged in the smoke exhaust pipe, wherein the bracket comprises an annular frame, a cross beam arranged in the middle of the annular frame and two hinging seats arranged on the annular frame, and the two hinging seats are respectively positioned at two end sides of the cross beam; the anti-downdraft pipeline further comprises:

the two backflow prevention plates are arranged on the same side of the bracket and used for opening or closing the through holes on the bracket;

the otic placode, the otic placode sets up on the anti-backflow board and along deviating from the direction of support extends, otic placode part protrusion the inward flange setting of anti-backflow board, two on the anti-backflow board the otic placode pass through same articulated shaft with articulated seat rotates to be connected, it has the hinge hole that supplies the articulated shaft to pass to open on the otic placode, the axis of hinge hole with the projection of anti-backflow board in being on a parallel with in the plane of anti-backflow board is disjoint.

Compared with the background technology, the anti-downdraft pipeline has the following beneficial effects: according to the utility model, the lug plates are arranged on one side of the backflow prevention plate far away from the bracket, the lug plates on the two backflow prevention plates are hinged with the hinge seat through the same hinge shaft, and the axis of the hinge hole and the projection of the backflow prevention plate in the plane parallel to the backflow prevention plates are not intersected, so that the two backflow prevention plates share the same hinge shaft, the hinge shaft is positioned on one side of the backflow prevention plate far away from the bracket, and a space exists between the hinge shaft and the inner edge of the backflow prevention plate, the arrangement is such that the width of the splice joint between the two backflow prevention plates is not influenced by the size of the hinge shaft, a designer is allowed to set the inner edge of the backflow prevention plate as a straight edge, so that the splice joint formed by the two backflow prevention plates is a straight line, and the width of the cross beam is only required to be larger than the width of the splice joint, compared with the existing design mode of uneven splice joint, namely, the tightness is ensured, good backflow prevention effect is achieved, the resistance to be received in the flowing process is reduced, the smoke emission is smoother, and the combustion performance of the smoke gas is improved.

Further, the inner edge of the backflow preventing plate is provided with a straight edge. By adopting the design scheme, the splicing seam formed by the two backflow prevention plates is a straight line, so that the width of the cross beam is only required to be larger than that of the splicing seam, compared with the existing uneven design mode of the splicing seam, the width of the cross beam can be reduced, the flow resistance of smoke is reduced, and the combustion performance of the gas water heater is improved.

Further, the distance between the axis of the hinge hole and the inner edge of the backflow prevention plate is 0.6 mm-1 mm. In theory, the interval between the axis of the hinge hole and the inner edge of the backflow preventing plate can be zero, but the interval between the axis of the hinge hole and the inner edge of the backflow preventing plate is limited to be 0.6-1 mm, so that the width of the cross beam is ensured not to be too large, the cross beam has certain structural strength, and the cross beam is not easy to deform.

Further, the inner edge of the backflow preventing plate is provided with a first flanging, and the first flanging extends along the direction deviating from the bracket. Through adopting above-mentioned design, can improve the structural strength of preventing the refluence board for prevent the refluence board be difficult for deformation.

Further, the sealing device also comprises a sealing element arranged between the backflow preventing plate and the support and a fixing shaft arranged on the support, wherein the fixing shaft is positioned above the sealing element and compresses the sealing element on the support.

Further, the sealing member includes the sealing washer and sets up the sealing strip at the sealing washer middle part, the sealing strip with the crossbeam butt, the upper surface of sealing strip is sunken to have and is used for the recess, the fixed axle set up in the recess.

Further, the hinge seat is fixed on the annular frame.

Further, open on the annular frame and supply the logical groove that articulated seat passed, articulated seat with logical groove slip grafting is provided with the connecting strip between two articulated seat, the width of connecting strip is not greater than the width of crossbeam.

Further, a guide plate is further arranged on one side, away from the sealing piece, of the cross beam or the connecting strip, and the guide plate is narrowed on one side, close to the air inlet end of the smoke exhaust pipe.

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

a gas water heater comprises the anti-downdraft pipeline.

Compared with the background technology, the gas water heater has the beneficial effects that:

when the backflow preventing device is used, the backflow preventing pipeline is arranged at the smoke discharging interface of the gas water heater, as the lug plates are arranged on one side of the backflow preventing plate, which is far away from the bracket, and the lug plates on the two backflow preventing plates are hinged with the hinge seat through the same hinge shaft, and the axes of the hinge holes and the projections of the backflow preventing plates in the planes parallel to the backflow preventing plates are not intersected, so that the two backflow preventing plates share the same hinge shaft, the hinge shaft is positioned on one side of the backflow preventing plates, which is far away from the bracket, and a space exists between the hinge shaft and the inner edge of the backflow preventing plate, and the arrangement is such that the width of the splice joint between the two backflow preventing plates is not influenced by the size of the hinge shaft, so that a designer sets the inner edge of the backflow preventing plate as a straight edge, and the splice joint formed by the two backflow preventing plates is a straight line.

Drawings

FIG. 1 is a schematic diagram of the overall structure of the present utility model;

FIG. 2 is an exploded view of the present utility model;

FIG. 3 is a top view of the anti-reflux plate of the present utility model;

FIG. 4 is a side view of the anti-reflux plate of the present utility model;

FIG. 5 is a schematic view of the structure of the back flow prevention plate after closing;

FIG. 6 is a longitudinal cross-sectional view of the present utility model;

FIG. 7 is an enlarged schematic view of FIG. 4A in accordance with the present utility model;

fig. 8 is an enlarged schematic view of B of fig. 4 in accordance with the present utility model.

Description of the drawings: 1. a smoke exhaust pipe; 11. a first tube body; 12. a second tube body; 2. a bracket; 21. an annular frame; 211. a second flanging; 22. a cross beam; 23. a hinge base; 231. a connecting strip; 3. a backflow prevention plate; 31. ear plates; 311. a hinge hole; 32. a first flanging; 33. an inner edge; 4. a through hole; 5. a hinge shaft; 6. a seal; 61. a seal ring; 62. a sealing strip; 63. an avoidance groove; 64. sealing and back-off; 641. a convex edge is clamped; 642. a sealing protrusion; 7. a jack; 8. a fixed shaft; 9. a groove; 10. a through groove; 13. and a deflector.

Detailed Description

The following description of the embodiments of the present utility model 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 utility model, but not all embodiments. 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 understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the utility model and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the utility model.

The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present utility model, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "assembled" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; 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 will be understood in specific cases by those of ordinary skill in the art.

The embodiment of the utility model provides an anti-downdraft pipeline and a gas water heater comprising the same, which effectively reduce the flow resistance of smoke so as to improve the combustion performance of the water heater.

As shown in fig. 1 to 4, an anti-reverse air duct includes a smoke discharge pipe 1, a bracket 2 provided in the smoke discharge pipe 1, and an anti-reverse flow plate 3 provided on the bracket 2. Wherein, support 2 includes annular frame 21, sets up at the crossbeam 22 at annular frame 21 middle part and sets up two articulated seat 23 on support 2, annular frame 21 and exhaust pipe 1 fixed connection, and crossbeam 22 separates annular frame 21 and forms two through-holes 4 that the size is unanimous, and two articulated seat 23 are located the both ends side of crossbeam 22 respectively, and two articulated seat 23 all are located the one side that annular frame 21 deviates from exhaust pipe 1 air inlet end. The anti-backflow plate 3 is provided with two, and two anti-backflow plates 3 are all arranged on one side of the annular frame 21 deviating from the air inlet end of the smoke exhaust pipe 1, and the shape of the anti-backflow plate 3 is similar to that of the through hole 4, and the area of the anti-backflow plate 3 is larger than that of the through hole 4, and the anti-backflow plate 3 is used for opening or closing the through hole 4. The anti-backflow plate 3 is provided with two lug plates 31, the lug plates 31 extend towards the direction away from the support 2, the two lug plates 31 are respectively positioned at the corners of the inner edge 33 of the anti-backflow plate 3, the lug plates 31 are formed by cutting and turning over the corners of the anti-backflow plate 3, and part of the lug plates 31 protrudes out of the inner edge 33 of the anti-backflow plate 3; the otic placode 31 on two anti-backflow boards 3 is rotated through same articulated shaft 5 and articulated seat 23 and is connected, opens on the otic placode 31 and supplies articulated hole 311 that articulated shaft 5 passed, and the axis of articulated hole 311 and the projection of anti-backflow board 3 in the plane that is on a parallel with anti-backflow board 3 do not intersect, and the perpendicular distance between axis and the anti-backflow board 3 of articulated hole 311 is L1, and the distance of the axis of articulated hole 311 from the interior edge 33 one side of otic placode 31 protrusion anti-diversion board 3 is L2, and L1 is greater than L2.

It will be appreciated that the inner edge 33 of the anti-backflow plate 3 refers to the side of the anti-backflow plate 3 that is adjacent to the hinge shaft 5.

After the flue gas gets into in the smoke tube 1, thereby prevent that the back flow board 3 is blown by the air current and open through-hole 4, thereby make the flue gas can discharge smoothly, because articulated seat 23 sets up in the tip side of crossbeam 22, make the articulated point of preventing back flow board 3 and support 2 keep away from crossbeam 22, simultaneously with otic placode 31 setting up in the one side of preventing back flow board 3 keeping away from support 2, and otic placode 31 on two prevent back flow boards 3 rotate with articulated seat 23 through same articulated shaft 5, and the axis of hinge hole 311 and prevent back flow board 3 do not intersect in the projection that is on a parallel with the plane of preventing back flow board 3, make the width size of the joint seam between two prevent back flow boards 3 not receive the influence of articulated shaft 5 size, allow the designer to set up the inward flange 33 of preventing back flow board 3 as the straight flange, thereby make the joint seam that two prevent back flow boards 3 form be a straight line, so, the width of crossbeam 22 only need be greater than this width of concatenation can, compare in the not neat design mode of current preventing back flow board 3, can reduce the width of crossbeam 22, guarantee that the leakproofness is good in the effect of preventing back flow board 3, thereby the flue gas can reduce the combustion resistance, and the flue gas is more smooth and easy to flow, and the flue gas is discharged. When the gas burner stops working, the backflow preventing plate 3 resets under the action of gravity and closes the through hole 4, thereby playing a role in preventing down wind.

In some embodiments, it is preferable that the inner edge 33 of the backflow preventing plate 3 is provided as a straight edge, and the interval between the axis of the hinge hole 311 and the inner edge 33 of the backflow preventing plate 3 is 0.6mm to 1mm. The arrangement is that the splice seam formed by the two backflow prevention plates 3 is linear, compared with the existing design mode that the splice seam of the backflow prevention plates 3 is not regular, the width of the cross beam 22 can be reduced; meanwhile, the space between the axis of the hinge hole 311 and the inner edge 33 of the backflow preventing plate 3 is limited, so that the cross beam 22 can have certain structural strength on the premise of smaller width, and the cross beam 22 is not easy to deform, thereby being beneficial to improving the tightness.

In some embodiments, referring to fig. 2, in order to improve the structural strength of the backflow preventing plate 3, a punching process is performed on the backflow preventing plate 3 corresponding to the through holes 4 to improve the structural strength of the backflow preventing plate 3.

In some embodiments, referring to fig. 2 and 3, the inner edge 33 of the backflow preventing plate 3 is provided with a first flange 32, the first flange 32 extends in a direction away from the bracket 2, the first flange 32 is formed by cutting the inner edge 33 of the backflow preventing plate 3 and turning over at 90 degrees, and the movement track of the first flange 32 is not intersected with the hinge shaft 5. Through setting up first turn-ups 32 to strengthen the structural strength of preventing the refluence board 3, make the board 3 of preventing the refluence be difficult for deformation, be favorable to improving the leakproofness.

In some embodiments, referring to fig. 2, because the width of the cross beam 22 is smaller in the present utility model, in order to improve the structural strength of the cross beam 22, the cross beam 22 is stamped and formed such that the cross beam 22 has a plurality of folds, thereby improving the structural strength of the cross beam 22.

In some embodiments, referring to fig. 2, to further enhance the sealing, a seal 6 is provided between the bracket 2 and the anti-wind down plate, the seal 6 covering at least the cross beam 22 and the periphery of the through hole 4. In this embodiment, the sealing member 6 is made of high temperature resistant rubber, the sealing member 6 covers the annular frame 21 and the cross beam 22, and the sealing member 6 is provided with a avoiding groove 63 for avoiding the hinge seat 23. By arranging the sealing piece 6, the tightness of the connection between the backflow prevention plate 3 and the bracket 2 can be effectively enhanced, and accordingly, the backflow prevention effect is enhanced.

In some embodiments, referring to fig. 2 and 5 and fig. 7, in order to facilitate installation of the sealing member 6 and improve stability of the sealing member 6 after installation, the smoke exhaust pipe 1 is composed of a first pipe body 11 and a second pipe body 12, and it is easy to understand that the smoke exhaust pipe 1 may also be composed of three or more pipe bodies. The annular frame 21 is provided with a second flanging 211 and is covered on the end part of the first pipe body 11 through the second flanging 211, and the first pipe body 11, the annular frame 21 and the second pipe body 12 are fixedly connected. In this embodiment, the first pipe 11, the annular frame 21, and the second pipe 12 are fixed by welding, and in other embodiments, the first pipe 11, the annular frame 21, and the second pipe 12 may be connected by a bolt and a nut, which is not limited by the connection method of the first pipe 11, the annular frame 21, and the second pipe 12, and only needs to be tightly attached and fixedly connected. And one side of the sealing piece 6, which is close to the bracket 2, is provided with a sealing back-off 64, the sealing back-off 64 and the sealing piece 6 are integrally formed, and the sealing back-off 64 is clamped with the bracket 2. By providing the sealing back-off 64, the stability of the connection between the sealing element 6 and the bracket 2 is enhanced, so that the sealing element 6 is not easy to displace, and the sealing element 6 is ensured to provide a good sealing effect.

In some embodiments, referring to fig. 2 and 5 and fig. 7, the sealing member 6 includes a sealing ring 61 and a sealing strip 62, the sealing undercut 64 includes a clamping flange 641 and a sealing projection 642, the clamping flange 641 is disposed at an edge of the sealing ring 61, and the annular frame 21 is radially clamped with the clamping flange 641; the sealing protrusions 642 are provided in plurality, wherein one part of the sealing protrusions 642 is arranged on the sealing ring 61, the other part of the sealing protrusions 642 is arranged on the sealing strip 62, the annular frame 21 and the cross beam 22 are provided with insertion holes 7, the diameter of the sealing protrusions 642 is larger than the aperture of the insertion holes 7, and the sealing protrusions 642 are tightly inserted into the insertion holes 7. By providing the catching convex edge 641 and the sealing projection 642, the sealing member 6 is firmly connected with the bracket 2, and the sealing member 6 is not easy to loosen when the anti-wind down plate is opened, thereby maintaining good sealing property.

It will be appreciated that the seal 6 may also be secured to the support 2 in other ways, such as in alternative embodiments the seal 6 may also be glued to the support 2.

In some embodiments, referring to fig. 5 and 6 and 8, the anti-wind down pipe further comprises a fixed shaft 8, the fixed shaft 8 being arranged above the sealing strip 62 and being used to press the sealing member 6 against the support 2. In this embodiment, the fixed shaft 8 sequentially passes through the two hinge seats 23, and both ends of the fixed shaft 8 are abutted against the inner wall of the smoke exhaust pipe 1. The upper surface of sealing strip 62 is sunken to have the recess 9 that is used for supplying fixed axle 8 to place, and the both ends of recess 9 extend to link up sealing washer 61, and after fixed axle 8 placed in recess 9, fixed axle 8 did not bulge sealing strip 62's upper surface setting for fixed axle 8 can not hinder the upset of preventing backflow board 3 on stabilizing sealing member 6's basis.

In some embodiments, referring to fig. 2, a through groove 10 for passing through a hinge seat 23 is formed on the annular frame 21, the hinge seat 23 is in sliding connection with the through groove 10, a connecting strip 231 is arranged between the two hinge seats 23, and the width of the connecting strip 231 is not greater than that of the cross beam 22; in this embodiment, the width of the connecting bar 231 is smaller than the width of the cross beam 22 and larger than the aperture of the insertion hole 7. The connection bar 231 is also provided with a jack 7 through which the sealing protrusion 642 passes. When the hinge seat 23 is installed, the hinge seat 23 passes through the through groove 10 and makes the connecting strip 231 abut against the cross beam 22, then the sealing bulge 642 passes through the insertion holes 7 on the cross beam 22 and the connecting strip 231 once, and the connecting strip 231 and the cross beam 22 are tensioned by utilizing the sealing bulge 642 to be matched with the sealing strip 62. Through setting up connecting strip 231, increase the thickness of crossbeam 22 indirectly to be favorable to improving the structural strength of crossbeam 22, make crossbeam 22 be difficult for the deformation. In other embodiments, the hinge base 23 may be directly fixed to the ring frame 21, such as by welding the hinge base 23 to the ring frame 21 or fastening the hinge base to the ring frame 21 with bolts for assembly.

In some embodiments, referring to fig. 6 and 8, the side of the cross beam 22 or the connecting strip 231 facing away from the sealing member 6 is further provided with a baffle 13, and the side of the baffle 13 near the air inlet end of the smoke exhaust pipe 1 is narrowed. It will be appreciated that when the hinge seat 23 is welded to the bracket 2, the deflector 13 is fixed to the side of the cross beam 22 facing away from the seal 6; when the hinge seat 23 is arranged to be inserted into the annular frame 21, the deflector 13 is fixed to the side of the connecting strip 231 facing away from the sealing element 6 for installation. Through setting up guide plate 13, guide plate 13 plays the guide effect to the flue gas for the flue gas flows to through-hole 4 as far as possible, further reduces the resistance that the flue gas received at the flow in-process, makes gas heater smoke discharging more smooth and easy, thereby is favorable to improving gas heater's combustion performance.

In some embodiments, referring to fig. 6, the side of the baffle 13 near the air inlet end of the smoke exhaust pipe 1 is in an isosceles triangle narrowing arrangement, and the baffle 13 adopts a symmetrical structure design, so that the processing is convenient, and the smoke flow is more uniform, thereby being beneficial to the smoke emission.

In some embodiments, referring to fig. 8, since the baffle 13 adopts a triangular structure design, the strength is high, so that the baffle 13 is hollow, the weight of the baffle 13 can be reduced, the material can be saved, and the load of the beam 22 can be reduced, so that the beam 22 is not easy to deform.

The utility model relates to a gas water heater, which comprises an anti-downdraft pipeline, and when the gas water heater is used, the air inlet end of the anti-downdraft pipeline is connected with a smoke exhaust interface of the gas water heater.

The flue gas generated in the working process of the gas water heater enters the smoke exhaust pipe 1, the air backflow preventing plate blows up under the action of the flue gas, so that the through hole 4 is communicated, and the flue gas is exhausted from the air outlet end of the smoke exhaust pipe 1 through the through hole 4. According to the utility model, the hinge seat 23 is arranged at the end part side of the cross beam 22, so that the hinge point of the backflow prevention plate 3 and the support 2 is far away from the cross beam 22, the ear plates 31 extend towards the direction away from the support 2, the ear plates 31 on the two backflow prevention plates 3 are rotationally connected with the hinge seat 23 through the same hinge shaft 5, the axis of the hinge hole 311 and the projection of the backflow prevention plate 3 in the plane parallel to the backflow prevention plate 3 are not intersected, the width of the splice joint between the two backflow prevention plates 3 is not influenced by the size of the hinge shaft 5, and the inner edge 33 of the backflow prevention plate 3 is set to be a straight edge, so that the splice joint formed by the two backflow prevention plates 3 is a straight line, and therefore, the width of the cross beam 22 only needs to be larger than the width of the splice joint, compared with the existing design mode of the splice joint of the backflow prevention plate 3, the width of the cross beam 22 can be reduced, namely the tightness is ensured, a good backflow prevention effect is achieved, the resistance to be reduced, the hot water resistance in the flowing process is enabled, the flue gas emission is smoother, and the flue gas combustion performance of the flue gas is improved. When the gas burner stops working, the backflow preventing plate 3 resets under the action of gravity and closes the through hole 4, thereby playing a role in preventing down wind.

In the specific content of the above embodiment, any combination of the technical features may be performed without contradiction, and for brevity of description, all possible combinations of the technical features are not described, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The foregoing detailed description of the embodiments presents only a few embodiments of the present utility model, which are described in some detail and are not intended to limit the scope of the present utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims (10)

1. Prevent down wind pipeline, including exhaust fume pipe (1) and support (2) of setting in exhaust fume pipe (1), its characterized in that:

the support (2) comprises an annular frame (21), a cross beam (22) arranged in the middle of the annular frame (21) and two hinging seats (23) arranged on the annular frame (21), wherein the two hinging seats (23) are respectively positioned at two end sides of the cross beam (22); the anti-downdraft pipeline further comprises:

the two backflow prevention plates (3) are arranged on the same side of the bracket (2) and used for opening or closing the through holes (4) on the bracket (2);

otic placode (31), otic placode (31) set up on preventing backflow board (3) and along deviating from the direction of support (2) extends, otic placode (31) part protrusion prevent inner edge (33) setting of backflow board (3), two on preventing backflow board (3) otic placode (31) through same articulated shaft (5) with articulated seat (23) rotate and be connected, it has hinge hole (311) that supplies articulated shaft (5) to pass to open on otic placode (31), the axis of hinge hole (311) with prevent backflow board (3) are being on a parallel with prevent the projection disjoint in the plane of backflow board (3).

2. The anti-downdraft pipe of claim 1, wherein: the inner edge (33) of the backflow prevention plate (3) is arranged in a straight edge mode.

3. The anti-downdraft pipe of claim 2, wherein: the distance between the axis of the hinge hole (311) and the inner edge (33) of the backflow prevention plate (3) is 0.6 mm-1 mm.

4. The anti-downdraft pipe of claim 1, wherein: the inner edge (33) of the backflow prevention plate (3) is provided with a first flanging (32), and the first flanging (32) extends in a direction away from the bracket (2).

5. The anti-downdraft pipe of claim 2, wherein: the anti-backflow device is characterized by further comprising a sealing piece (6) arranged between the anti-backflow plate (3) and the support (2) and a fixing shaft (8) arranged on the support (2), wherein the fixing shaft (8) is positioned above the sealing piece (6) and compresses the sealing piece (6) on the support (2).

6. The anti-downdraft pipe of claim 5, wherein: the sealing element (6) comprises a sealing ring (61) and a sealing strip (62) arranged in the middle of the sealing ring (61), the sealing strip (62) is abutted to the cross beam (22), a groove (9) is recessed in the upper surface of the sealing strip (62), and the fixing shaft (8) is arranged in the groove (9).

7. The anti-downdraft pipe of claim 1, wherein: the hinge seat (23) is fixed on the annular frame (21).

8. The anti-downdraft pipe of claim 6, wherein: the annular frame (21) is provided with a through groove (10) for the hinge seat (23) to pass through, the hinge seat (23) is in sliding connection with the through groove (10), a connecting strip (231) is arranged between the two hinge seats (23), and the width of the connecting strip (231) is not greater than that of the cross beam (22).

9. The anti-wind down pipe according to claim 8, wherein: and a guide plate (13) is further arranged on one side of the cross beam (22) or the connecting strip (231) away from the sealing piece (6), and one side of the guide plate (13) close to the air inlet end of the smoke exhaust pipe (1) is narrowed.

10. The gas water heater, its characterized in that: an anti-wind down pipe comprising any one of claims 1 to 9.