CN212409080U

CN212409080U - Smoke pipe elbow component

Info

Publication number: CN212409080U
Application number: CN202020802425.5U
Authority: CN
Inventors: 张洪鑫; 万旭杰; 孙连政
Original assignee: Hisense Guangdong Kitchen and Bath System Co Ltd
Current assignee: Hisense Guangdong Kitchen and Bath System Co Ltd
Priority date: 2020-05-14
Filing date: 2020-05-14
Publication date: 2021-01-26
Anticipated expiration: 2030-05-14

Abstract

The utility model discloses a tobacco pipe elbow subassembly relates to gas heater technical field. The gas water heater can prevent external wind from flowing backwards, and does not occupy installation space and influence attractiveness on the premise of improving the use safety of the gas water heater. The utility model comprises a smoke tube elbow, wherein the smoke tube elbow comprises a bending section, a first straight tube section and a second straight tube section which are connected with the two ends of the bending section; the one-way air door mechanism is arranged in the first straight pipe section or the second straight pipe section. The utility model discloses can be used to promote the performance of tobacco pipe elbow.

Description

Smoke pipe elbow component

Technical Field

The utility model relates to a gas heater technical field especially relates to a tobacco pipe elbow subassembly.

Background

The existing gas water heater's exhaust pipe generally includes the tobacco pipe elbow and the pipe of discharging fume that connect gradually in the exit of collection petticoat pipe top section of thick bamboo. The existing smoke pipe elbow comprises a bending section and straight pipe sections connected to two ends of the bending section, and because the inside of the smoke exhaust pipe and the inside of the smoke pipe elbow directly form an air channel, the existing gas water heater can be provided with a non-return device for preventing the backflow of external air in a smoke collection hood top cylinder. However, as the service life of the air conditioner is prolonged, the air conditioner may be damaged, and the anti-backflow effect is deteriorated.

When the gas water heater is used, if external wind flows back into the gas water heater, the water heater can not burn normally, the dangerous situation of CO poisoning and even burning can be caused, and the life and property safety of a user can be threatened. In addition, in cold winter, if external cold air flows backwards into the water heater, water in an internal pipeline is easy to freeze, a water pipe is frozen, and the water heater is damaged. In more serious cases, water can flow out of the frozen water pipe, so that furniture is damaged, and property safety of users is threatened.

Because no building or tree is blocked, the external wind power of a high-rise user home is much larger than that of a low-rise user, and therefore, the possibility of external wind flowing backwards is higher for the high-rise user in windy weather. After-sales personnel therefore generally recommend high-rise residents to install a separate anti-backflow device above the gas water heater, but installation of the device not only takes up additional installation space, but also affects the aesthetics.

SUMMERY OF THE UTILITY MODEL

An embodiment of the utility model provides a tobacco pipe elbow subassembly can prevent that external wind from flowing backward, improves gas heater's safety in utilization's prerequisite under, still does not occupy installation space and does not influence the aesthetic property.

In order to achieve the above object, an embodiment of the present invention provides a smoke tube elbow assembly, including: the smoke pipe elbow comprises a bending section, a first straight pipe section and a second straight pipe section, wherein the first straight pipe section and the second straight pipe section are connected to two ends of the bending section; and the one-way air door mechanism is arranged in the first straight pipe section or the second straight pipe section.

The embodiment of the utility model provides a tobacco pipe elbow subassembly, including tobacco pipe elbow and one-way air door mechanism, wherein, the tobacco pipe elbow is including the section of bending and connect in the first straight tube section and the second straight tube section at the section both ends of bending, and one-way air door mechanism is located first straight tube section or second straight tube section. After the one-way air door mechanism is connected with the gas water heater, the opening direction of the one-way air door mechanism is the same as the flow direction of waste gas generated by the gas water heater and is opposite to the entering direction of outside wind, when the gas water heater normally burns and discharges smoke, the one-way air door mechanism is opened, and the waste gas generated by the gas water heater flows out; when the outside is strong wind, the one-way air door mechanism is closed, so that the outside wind can be prevented from flowing backwards, and the use safety of the gas water heater can be improved. In addition, because the one-way air door mechanism is positioned in the first straight pipe section or the second straight pipe section, the mounting space is not additionally occupied, and the attractiveness is not influenced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a front cross-sectional view of a smoke tube elbow assembly according to an embodiment of the present invention;

FIG. 2 is a side view of a smoke tube elbow assembly according to an embodiment of the present invention;

FIG. 3 is a schematic perspective view of a unidirectional damper mechanism in a smoke tube elbow assembly according to an embodiment of the present invention;

fig. 4 is a schematic perspective view of an angle of a support frame in a smoke tube elbow assembly according to an embodiment of the present invention;

fig. 5 is a schematic perspective view of another angle of the support frame in the smoke tube elbow assembly according to the embodiment of the present invention;

fig. 6 is a schematic perspective view of a first air door in a smoke tube elbow assembly according to an embodiment of the present invention;

fig. 7 is a schematic perspective view of a second damper in a smoke tube elbow assembly according to an embodiment of the present invention;

fig. 8 is a schematic view of an installation structure of a smoke tube elbow assembly according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "central", "upper" and "lower" are used herein,

Lower, front, rear, left, right, vertical and horizontal,

The references to "top," "bottom," "inner," "outer," and the like are based on the orientation or positional relationship shown in the drawings and are intended only for convenience in describing the invention and for simplicity in description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the invention.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; the specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The terms "first", "second" and "first" 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 defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

Referring to fig. 1 and 2, the smoke tube elbow component of the embodiment of the present invention includes a smoke tube elbow 1 and a one-way air door mechanism 2, wherein, the smoke tube elbow 1 includes a bending section 11 and a first straight tube section 12 and a second straight tube section 13 connected to both ends of the bending section, and the one-way air door mechanism 2 is disposed in the first straight tube section 12 or the second straight tube section 13, and does not occupy extra installation space and does not affect the aesthetic property.

Referring to fig. 8, in some embodiments, the one-way damper mechanism 2 is disposed in the first straight pipe section 12, the outlet of the first straight pipe section 12 is connected to the inlet of the smoke pipe 3, the outlet of the smoke pipe 3 is communicated with the outside air, the second straight pipe section 13 is connected to the hood collecting top cylinder 41 of the gas water heater 4, and the non-return device 42 is disposed in the hood collecting top cylinder 41. The opening direction of the one-way damper mechanism 2 is towards the outlet direction of the first straight pipe section 12, the same as the flow direction of the waste gas generated by the gas water heater 4, and opposite to the entering direction of the outside wind (the entering direction of the outside wind is shown by an arrow). When the combustion heat exchange system 43 in the gas water heater 4 burns and discharges the flue gas normally, the one-way air door mechanism 2 is opened, and the waste gas generated by the gas water heater 4 is discharged through the smoke pipe elbow 1 and the smoke pipe 3; when the outside is strong wind, the one-way air door mechanism 2 is closed, so that the outside wind can be prevented from flowing backwards, and the use safety of the gas water heater 4 can be improved. In addition, because the one-way air door mechanism 2 is vertically arranged with the backstop 42 in the top cylinder, even if a small amount of outside air enters the smoke pipe elbow 1, the wind power is greatly reduced after passing through the bending pipe 11, thereby reducing the risk that the backstop 42 is damaged.

In other embodiments, the one-way damper mechanism 2 may also be disposed in the second straight pipe section 13, the outlet of the first straight pipe section 12 is still connected to the inlet of the smoke pipe 3, the outlet of the smoke pipe 3 is connected to the outside air, and the second straight pipe section 13 is connected to the smoke collecting hood top cylinder 41 in the gas water heater 4. The opening direction of the one-way damper mechanism 2 is still directed toward the outlet direction of the first straight duct section 12. The structure can also prevent outside wind from flowing backwards, thereby improving the use safety of the gas water heater 4.

The support frame 21 has various available connection modes with the first straight pipe section 12 or the second straight pipe section 13, for example, the support frame 21 can be adhered to the inner wall of the first straight pipe section 12 or the second straight pipe section 13; as another example, the support bracket 21 may be welded to the inner wall of the first straight pipe section 12 or the second straight pipe section 13.

The support frame 21 has various structures, for example, the support frame 21 may be a support plate, the support plate is provided with a vent hole 211, and the outer edge of the support plate is connected with the inner wall surface of the first straight pipe section 12 or the second straight pipe section 13 in a sealing manner, such as welding; as another example, referring to fig. 4, the edge of the support frame 21 may form a third flange 214, and referring to fig. 1, an outer wall surface of the third flange 214 is connected with an inner wall surface of the first straight pipe section 12 or the second straight pipe section 13 in a sealing manner, such as welding; if the supporting frame 21 is adopted as the supporting plate, the connecting surface of the supporting frame 21 and the first straight pipe section 12 or the second straight pipe section 13 is the outer edge of the supporting frame 21, and as the supporting frame 21 is a plate, the plate thickness needs to be increased if the connection is firm, but the weight is inevitably increased by increasing the plate thickness, so that the cost is increased and the installation is inconvenient; if the edge of the support frame 21 is adopted to form the third flange 214, the third flange 214 can be connected with the first straight pipe section 12 or the second straight pipe section 13, and the direct contact surface of the third flange 214 and the first straight pipe section 12 or the second straight pipe section 13 is the outer wall surface of the third flange 214, so that compared with the situation that the plate thickness is directly increased, under the same stress condition, the weight increased by adopting the flange is smaller, the increased cost is less, and the installation is easier, therefore, the edge of the support frame 21 is preferably adopted to form the third flange 214.

The support frame 21 and the first straight pipe section 12 or the second straight pipe section 13 have various realizable positional relationships, and for example, an included angle between a center line of the support frame 21 and an axis of the first straight pipe section 12 or the second straight pipe section 13 may be an acute angle; as another example, referring to fig. 1, an included angle between a center line of the support frame 21 and an axis of the first straight pipe section 12 or the second straight pipe section 13 may be a right angle, that is, the support frame 21 is disposed perpendicular to the axis of the first straight pipe section 12 or the second straight pipe section 13; if a structure that an included angle between the center line of the support frame 21 and the axis of the first straight pipe section 12 or the second straight pipe section 13 is an acute angle is adopted, when external wind blows, the wind direction of the external wind is not perpendicular to that of the air door on the support frame 21, so that the wind force acting on the air door is smaller than the actual wind force under the same wind force; if the support frame 21 is perpendicular to the axis of the first straight pipe section 12 or the second straight pipe section 13, when external wind blows, the actual wind acting on the air door is equal to the actual wind, the air door can be more reliably pressed on the support frame 21, and the reliability of the one-way air door mechanism 2 can be improved.

The one-way damper mechanism 2 has various realizable structures, for example, the one-way damper mechanism 2 may include a damper and an articulated shaft, wherein the damper is matched with an internal passage of the first straight pipe section 12 or the second straight pipe section 13, the damper is fixed inside the first straight pipe section 12 or the second straight pipe section 13 through the articulated shaft penetrating through the damper, the damper can rotate around the articulated shaft, the internal passage of the first straight pipe section 12 or the second straight pipe section 13 is opened or closed, and two ends of the articulated shaft are arranged inside the first straight pipe section 12 or the second straight pipe section 13 and are correspondingly articulated with two sides of the first straight pipe section 12 or the second straight pipe section 13. The structure has the disadvantage that the air door and the first straight pipe section 12 or the second straight pipe section 13 are sealed through the matching between the outer edge of the air door and the inner wall of the channel, and the requirement on the machining precision of parts is high. As another example, referring to fig. 1 and 3, the one-way damper mechanism 2 may further include a support bracket 21 and a damper 22, and an outer edge of the support bracket 21 is sealingly connected to an inner wall surface of the first straight pipe section 12 or the second straight pipe section 13. It should be noted that the setting position of the one-way damper mechanism 2 is not unique, and when the one-way damper mechanism 2 is set in the first straight pipe section 12, the outer edge of the support frame 21 is in sealed connection with the inner wall surface of the first straight pipe section 12; when the one-way damper mechanism 2 is disposed inside the second straight pipe section 13, the outer edge of the support bracket 21 is sealingly connected to the inner wall surface of the second straight pipe section 13. Since the support frame 21 is provided with the vent hole 211, the damper 22 is hinged at the vent hole 211, and the damper 22 can be opened only to one side of the support frame 21. Specifically, the air door 22 can be folded to open and close, when the gas water heater 4 burns and discharges smoke normally, the air door 22 is turned to one side of the support frame 21 to open under the action of the smoke, and the smoke is discharged normally; when external wind blows to the inside of gas heater 4, air door 22 rotates to the direction opposite with the opening direction and closes under the effect of external wind-force, until air door 22 and support frame 21 contact, at this moment, under the effect of external wind-force, ventilation hole 211 department is located to air door 22 lid to compressed tightly can prevent that external wind from flowing backward. The advantage of this structure is that, when air door 22 was in the closed condition, air door 22 lid located the ventilation hole 211 department of support frame 21, and under the effect of external wind force, air door 22 can be compressed tightly on support frame 21, and support frame 21 can play the effect of support to air door 22 simultaneously, and consequently, external wind force is big more, and the sealed effect of the one-way air door mechanism 2 of this structure is better. Therefore, the one-way damper mechanism 2 preferably includes a structure of the support frame 21 and the damper 22.

The number of the ventilation holes 211 is not exclusive, and for convenience of manufacture, the number of the ventilation holes 211 may be one, and correspondingly, the number of the dampers 22 may be one, and the dampers 22 are hinged at the ventilation holes 211. As another example, referring to fig. 3, 4 and 5, the vent holes 211 may further include first and

second vent holes

2111 and 2112, and the corresponding damper 22 includes first and

second dampers

221 and 222, the first damper 221 being hinged at the first vent hole 2111, and the second damper 222 being hinged at the second vent hole 2112. If the structure that the number of the vent holes 211 is one is adopted, under the condition that the flow areas of the vent holes 211 are the same, the volume of the air door 22 is larger, the corresponding mass is also larger, and during normal smoke discharge, the wind power required for opening the air door 22 is also larger, which may cause unsmooth smoke discharge; if the vent hole 211 comprises the first vent hole 2111 and the second vent hole 2112, under the condition that the flow area of the vent hole 211 is the same, the volumes of the first damper 221 and the second damper 222 are smaller, the corresponding masses are also smaller, and the wind power required when a single damper is opened is also smaller, so that the first damper 221 and the second damper 222 are easier to open and the smoke discharge is smoother; therefore, the vent hole 211 preferably includes a structure of the first vent hole 2111 and the second vent hole 2112.

Referring to fig. 8, in some embodiments, the one-way damper mechanism 2 is located in the first straight pipe section 12, the first straight pipe section 12 is arranged in a horizontal direction, and the first damper 221 may be located above the second damper 222, which makes the second damper 222 easier to close under the action of gravity. Of course, in other embodiments, the first damper 221 may be positioned to the left or right of the second damper 222, which is not limited herein.

In some embodiments, the periphery of the opening of the first vent 2111 may be a plane, when the one-way damper mechanism 2 is closed, the first damper 221 is disposed on the periphery of the opening of the first vent 2111 in a covering manner, and likewise, the periphery of the opening of the second vent 2112 may also be a plane, when the one-way damper mechanism 2 is closed, the second damper 222 is disposed on the periphery of the opening of the first vent 2111 in a covering manner; in still other embodiments, referring to fig. 3 and 4, the mouth of the first vent 2111 may form a first flange 212, and the first damper 221 is covered on the first flange 212; meanwhile, the mouth of the second ventilation hole 2112 may form a second cuff 213, and the second damper 222 is covered on the second cuff 213. If the structure that the peripheries of the openings of the first vent hole 2111 and the second vent hole 2112 are both flat is adopted, the contact area between the first damper 221 and the periphery of the opening of the first vent hole 2111 is large, the contact area between the second damper 222 and the periphery of the opening of the second vent hole 2112 is also large, and sealing is needed between each damper and the periphery of the corresponding vent hole, so that the area needing finish machining is large, and the machining cost is high. If the mouth parts of the first vent holes 2111 and the second vent holes 2112 form a flanging structure, the contact area between each air door and the corresponding flanging is small due to the small size of the end surface of the flanging, so the area needing fine machining is small, and the machining cost is low; therefore, the mouths of the first ventilation hole 2111 and the second ventilation hole 2112 are preferably formed in a flanged structure.

There are various hinge manners that the first damper 221 and the second damper 222 can be hinged, for example, the first damper 221 and the second damper 222 can be hinged on different hinge shafts respectively; as another example, referring to fig. 3, the first damper 221 and the second damper 222 may also be hinged to the same hinge shaft 23, and the first damper 221 and the second damper 222 are symmetrically disposed with respect to the hinge shaft 23; if the first air door 221 and the second air door 222 are respectively hinged on different hinged shafts, at least two hinged shafts are required, and the processing and the assembly are inconvenient; if first air door 221 and second air door 222 also articulate on same articulated shaft 23, then only need set up an articulated shaft 23, processing and assembly are more convenient, can practice thrift manufacturing cost. Therefore, it is preferable that the first damper 221 and the second damper 222 are hinged to the same hinge shaft 23.

Meanwhile, since the first damper 221 and the second damper 222 are symmetrically arranged relative to the hinge shaft 23, the stressed areas of the first damper 221 and the second damper 222 are also equal, the opening and closing frequency of the first damper 221 and the second damper 222 is also close, and the phenomenon that one damper is damaged before the other damper due to more opening and closing times can be avoided. In addition, since the hinge shaft 23 is located at the position where the radial dimension is the largest in the support frame 21, the length of the hinge shaft 23 may be longer, and the contact area of the first damper 221 and the second damper 222 with the hinge shaft 23 may also be larger, whereby the first damper 221 and the second damper 222 are more reliably hinged.

Referring to fig. 4, in some embodiments, two through holes 217 are formed in the third flange 214, and the two through holes 217 are coaxially disposed. Referring to fig. 3, both ends of the hinge shaft 23 pass through the two through holes 217, respectively. Referring to fig. 6, the first damper 221 includes a first flap 2211 and a first boss 2212; referring to fig. 7, the second damper 222 includes a second flap 2221 and two second bushings 2222; referring to fig. 3, the first shaft sleeve 2212 and the two second shaft sleeves 2222 are sleeved on the hinge shaft 23, and when the first air door 221 and the second air door 222 are hinged on the hinge shaft 23, the first shaft sleeve 2212 is located between the two second shaft sleeves 2222, so that the first turning plate 2211 and the second turning plate 2221 are stressed more uniformly, and the risk of deformation of the first turning plate 2211 and the second turning plate 2221 can be reduced. In addition, the first damper 221 and the second damper 222 can only move along the axial direction of the hinge shaft 23 at the same time, so that the first damper 221 and the second damper 222 are not dislocated, and are convenient to limit the two.

Referring to fig. 3 and 4, in some embodiments, the third flange 214 is partially inwardly recessed to form two recesses 216, two through holes 217 are respectively formed in the corresponding recesses 217, and both ends of the hinge shaft 23 respectively protrude outside the two through holes 217. This structure ensures that the hinge shaft 23 can be reliably mounted on the third flange 214 without affecting the mounting of the support frame 21.

Referring to fig. 3, when the inside waste gas of gas heater 4 is discharged, first air door 221 overturns downwards and opens, and second air door 222 overturns downwards and opens, if the upset angle of first air door 221 and second air door 222 is not spacing this moment, if the air current is big enough, first air door 221 will laminate with second air door 222 mutually, at this moment, even if the external world is windy, also can't be closed with first air door 221 with second air door 222, and then lead to one-way air door mechanism 2 can't play and prevent the effect of flowing backwards.

In some embodiments, the one-way damper mechanism 2 further includes a stopping member, and the stopping member is used to prevent the first damper 221 and the second damper 222 from being continuously turned over and opened after being opened to a preset angle, so that the first damper 221 and the second damper 222 can be effectively prevented from being attached to each other, and the phenomenon that the one-way damper mechanism 2 cannot prevent backflow is avoided.

There are various possible structures of the stop member, for example, the stop member may be a stop block disposed on the first damper 221 or the second damper 222, for example, the stop block is disposed on the first damper 221, and when the first damper 221 and the second damper 222 are turned and opened to a preset angle, the stop block abuts against the second damper 222, and at this time, the first damper 221 and the second damper 222 cannot be turned any more; as another example, referring to fig. 3 and 4, the stop member may be a stop piece 215, one end of the stop piece 215 is fixed to a side of the third flange 214 away from the support frame 21, the other end of the stop piece 215 extends to a side of the first damper 221 and the second damper 222 away from the support frame 21, and a gap is formed between the stop piece 215 and the first damper 221 and the second damper 222, and the gap may satisfy that the first damper 221 and the second damper 222 may contact the stop piece 215 when being turned up to a preset angle; if the structure that the stop block is arranged on the first damper 221 or the second damper 222 is adopted, the stop block needs to be fixed on the first damper 221 or the second damper 222, so that the first damper 221 or the second damper 222 may be deformed, and the anti-backflow effect of the one-way damper mechanism 2 is deteriorated; if the stopper piece 215 is provided in the third flange 214, the back draft prevention effect of the one-way damper mechanism 2 is not obtained, and therefore, it is preferable to provide the stopper piece 215 in the third flange 214.

Referring to fig. 1, the section of bending 11 in tobacco pipe elbow 1 can also be the ripple pipeline section for ordinary elbow section, compares ordinary return bend, and the bellows is adding man-hour in buckling, and the wall thickness can not change, consequently the inhomogeneous phenomenon of wall thickness can not appear, and the performance is more reliable, in addition, adopts the ripple pipeline section, can make the utility model discloses the bend angle of the tobacco pipe elbow 1 among the tobacco pipe elbow subassembly is adjusted at the small range, and is right the utility model discloses the required precision of tobacco pipe elbow subassembly installation is lower, can practice thrift the cost.

In addition, the embodiment of the utility model provides a tobacco pipe elbow subassembly also can be arranged in the pipe of discharging fume of carbon stove, prevents CO poisoning, has great application prospect in rural area.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A smoke tube elbow assembly comprising:

the smoke pipe elbow comprises a bending section, a first straight pipe section and a second straight pipe section, wherein the first straight pipe section and the second straight pipe section are connected to two ends of the bending section; its characterized in that, tobacco pipe elbow subassembly still includes:

and the one-way air door mechanism is arranged in the first straight pipe section or the second straight pipe section.

2. The smoke tube elbow assembly of claim 1 wherein said one-way damper mechanism comprises:

the outer edge of the support frame is connected with the inner wall surface of the first straight pipe section or the second straight pipe section in a sealing mode; the support frame is provided with a vent hole;

the air door is hinged to the vent hole and can be turned and opened to one side of the support frame.

3. The smoke tube elbow assembly of claim 2,

the vent holes comprise a first vent hole and a second vent hole;

the dampers comprise a first damper and a second damper;

the first air door is hinged at the first ventilation hole, and the second air door is hinged at the second ventilation hole.

4. The smoke tube elbow assembly of claim 3,

first air door with first air door articulates on same articulated shaft, just first air door with the second air door for the articulated shaft symmetry sets up.

5. The smoke tube elbow assembly of claim 3,

a first flanging is formed at the opening part of the first vent hole, and the first air door cover is arranged on the first flanging;

and a second flanging is formed at the opening part of the second ventilation hole, and the second air door cover is arranged on the second flanging.

6. The smoke tube elbow assembly of claim 4,

and the edge of the support frame forms a third flanging, and the outer wall surface of the third flanging is in sealing connection with the inner wall surface of the first straight pipe section or the second straight pipe section.

7. The smoke tube elbow assembly of claim 6,

the one-way air door mechanism further comprises a stopping piece, and the stopping piece is used for preventing the first air door and the second air door from being continuously turned and opened after being opened to a preset angle.

8. The smoke tube elbow assembly of claim 7,

stop the position piece and to stop the position piece, the one end of stopping the position piece is fixed the third turn-ups is kept away from on one side of support frame, the other end of stopping the position piece extends to first air door with the second air door is kept away from one side of support frame, stop the position piece with have the clearance between first air door and the second air door, this clearance can satisfy first air door with the second air door turn up when predetermineeing the angle can with stop the position piece and contact.

9. The smoke tube elbow assembly of any one of claims 2-8 wherein the support bracket is disposed perpendicular to the axis of the first straight tube section or the second straight tube section.

10. The smoke tube elbow assembly of claim 4 wherein said bend segment is a bellows segment.