CN214836487U

CN214836487U - Air duct connecting structure and air duct

Info

Publication number: CN214836487U
Application number: CN202023039554.2U
Authority: CN
Inventors: 栗磊; 李伟东; 汪义龙; 孙晓虎; 李永元; 沙兴锋; 张倩; 栗伟; 崔宝库; 何健; 徐浩; 高健勋
Original assignee: Huaneng Coal Technology Research Co Ltd
Current assignee: Huaneng Coal Technology Research Co Ltd
Priority date: 2020-12-16
Filing date: 2020-12-16
Publication date: 2021-11-23
Anticipated expiration: 2030-12-16

Abstract

The utility model provides a dryer connection structure and dryer relates to mine or tunnel ventilation technical field. The air duct connecting structure comprises an upstream barrel and a downstream barrel, wherein the upstream connecting end of the upstream barrel is detachably connected with the downstream connecting end of the downstream barrel; the upstream cylinder is connected with an annular skirt cylinder, and when the air duct conducts air, the air outlet end of the annular skirt cylinder is inserted into the downstream cylinder. The air duct comprises a plurality of sections of barrels which are connected in sequence, and the barrels all adopt the air duct connecting structure. When the air duct is used for guiding air, the air flow firstly flows into the upstream cylinder, then flows into the annular skirt cylinder and directly flows into the downstream cylinder through the air outlet end of the annular skirt cylinder, the air flow can flow into the downstream cylinder without flowing through the joint of the upstream cylinder and the downstream cylinder, so that the air leakage caused by the fact that the air flow flows through the joint of the upstream cylinder and the downstream cylinder is effectively reduced, the air quantity at the tail end of the air duct is correspondingly improved, and the air supplementing and air exchanging effects of the air duct on a tunneling working surface are ensured.

Description

Air duct connecting structure and air duct

Technical Field

The utility model relates to a mine or tunnel ventilation technical field particularly, relate to an dryer connection structure and dryer.

Background

In the mine or tunnel tunneling ventilation, the wind barrel is required to guide wind, the wind barrel is produced according to a fixed length for convenient transportation, standardization and serialization during manufacturing, so that a plurality of barrel bodies are required to be connected together for use during actual use, however, the sealing performance of the joint of the existing barrel bodies is poor, and in the wind guiding process of the wind barrel, the wind leakage at the joint of the barrel bodies is serious, so that the head-on wind quantity of a tunneling working face is insufficient.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing an dryer connection structure and dryer to the junction leakproofness of solving current barrel is relatively poor, and dryer wind-guiding in-process, the junction air leakage of barrel are comparatively serious, lead to the not enough technical problem of the amount of wind that the driving face is met.

In order to solve the problems, the utility model provides an air duct connecting structure, which comprises an upstream barrel and a downstream barrel, wherein the upstream connecting end of the upstream barrel is detachably connected with the downstream connecting end of the downstream barrel; the upstream cylinder is connected with an annular skirt cylinder, and when the air duct conducts air, the air outlet end of the annular skirt cylinder is inserted into the downstream cylinder.

Optionally, the upstream cylinder, the downstream cylinder and the annular skirt cylinder are all flexible cylinders.

Optionally, the annular skirt is a truncated cone, a reduced end of the annular skirt is coaxially connected with the upstream cylinder, and a flared end of the annular skirt serves as the air outlet end.

Optionally, the upstream connection end is connected to a first connection ring, the downstream connection end is connected to a second connection ring, one of the first connection ring and the second connection ring is a first magnetic ring, and the other of the first connection ring and the second connection ring is a second magnetic ring or an iron ring, and the first connection ring and the second connection ring are magnetically connected.

Optionally, the air duct connecting structure comprises an integral barrel, the first connecting ring is arranged around the outer wall of the integral barrel, the barrel section on one side of the first connecting ring forms the upstream barrel along the axial direction of the integral barrel, and the barrel section on the other side of the first connecting ring forms the annular skirt barrel.

Optionally, the upstream barrel is provided with a first locking member, the downstream barrel is provided with a second locking member, and the first locking member is detachably connected with the second locking member.

Optionally, one of the first locking member and the second locking member is a fastening band, the other one is a fastening buckle, the fastening band is provided with a plurality of fastening holes, and the plurality of fastening holes are arranged at intervals along the length direction of the fastening band;

the tightening buckle comprises a buckle ring, the buckle ring is connected with a cross arm, the cross arm divides the interior of the buckle ring into a first ring body and a second ring body, and the cross arm is hinged with a locking arm; the cross arm is connected to one of the upstream cylinder and the downstream cylinder, one end of the tightening belt is connected to the other of the upstream cylinder and the downstream cylinder, the other end of the tightening belt sequentially penetrates through the first ring body and the second ring body, and the locking arm is inserted into one of the tightening holes.

Optionally, one of two opposite end surfaces of the first connecting ring and the second connecting ring is provided with a limiting groove, the other end surface of the first connecting ring and the second connecting ring is provided with a limiting boss, and the limiting boss is inserted into the limiting groove in a matching manner when the first connecting ring and the second connecting ring are connected in a magnetic attraction manner.

Optionally, the plurality of sections of the cylinder are all identical.

The utility model also provides a dryer, including the barrel that the multistage connected gradually, the multistage above-mentioned dryer connection structure is all adopted to the barrel, along the air current direction in the dryer, in two sections adjacent barrels, the barrel that is located the upper reaches does upper reaches barrel among the dryer connection structure, the barrel that is located the low reaches does low reaches barrel among the dryer connection structure.

The utility model provides an air duct connecting structure, including the upper reaches barrel and the low reaches barrel that form part or whole dryer jointly, and be equipped with in the upper reaches barrel and be used for separating the fender to upper reaches barrel and low reaches barrel junction to improve the annular skirt section of thick bamboo of upper reaches barrel and low reaches barrel junction gas tightness. During installation, the air outlet end of the annular skirt cylinder is inserted into the downstream cylinder, and then the upstream connecting end is connected with the downstream connecting end, so that the connection between the upstream cylinder and the downstream cylinder is completed; when the dryer air guide, the air current at first flows into the upper reaches barrel, then flow in the annular skirt to in the air-out end direct flow low reaches barrel through the annular skirt, namely, the annular skirt keeps off in the junction inboard of upper reaches link and low reaches link along circumference, the air current need not to flow through this junction and can flow in the low reaches barrel, thereby effectively reduce the air leakage that the air current caused through the junction of upper reaches barrel and low reaches barrel, the terminal amount of wind of corresponding improvement dryer, ensure the air supplementing, the ventilation effect of dryer to the driving face.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be 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 embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic view of the connection state of an upstream wind tunnel and a downstream wind tunnel in the wind tunnel connection structure provided by the present invention;

fig. 2 is a schematic view of the air duct connection structure provided by the present invention when the upstream air duct and the downstream air duct are in a split state;

fig. 3 is a schematic view of another form of the air duct connection structure according to the present invention, wherein the air duct is in an upstream air duct and a downstream air duct split state.

Description of reference numerals:

100-an upstream cylinder; 200-a downstream cylinder; 300-annular skirt; 310-air outlet end; 400-a first connecting ring; 410-a limit groove; 500-a second connecting ring; 510-limiting a boss; 600-binding a belt; 610-fastening holes; 700-fastening and fastening; 710-a retaining ring; 720-cross arm; 730-a locking arm; 740-a first ring member; 750-a second ring body.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The present embodiment provides an air duct connecting structure, as shown in fig. 1 and fig. 2, including an upstream cylinder 100 and a downstream cylinder 200, where an upstream connecting end of the upstream cylinder 100 is detachably connected to a downstream connecting end of the downstream cylinder 200; the upstream cylinder 100 is connected with an annular skirt 300, and when the air duct conducts air, an air outlet end 310 of the annular skirt 300 is inserted into the downstream cylinder 200.

The air duct connecting structure provided by the embodiment comprises an upstream barrel 100 and a downstream barrel 200 which jointly form part or all of an air duct, and an annular skirt barrel 300 which is used for blocking the joint of the upstream barrel 100 and the downstream barrel 200 is arranged in the upstream barrel 100 so as to improve the air tightness of the joint of the upstream barrel 100 and the downstream barrel 200. During installation, the air outlet end 310 of the annular skirt 300 is inserted into the downstream cylinder 200, and then the upstream connecting end is connected with the downstream connecting end, so that the connection between the upstream cylinder 100 and the downstream cylinder 200 is completed; when the air duct conducts air, the air flow firstly flows into the upstream cylinder 100, then flows into the annular skirt 300 and directly flows into the downstream cylinder 200 through the air outlet end 310 of the annular skirt 300, namely, the annular skirt 300 is circumferentially separated and blocked at the inner side of the joint of the upstream connecting end and the downstream connecting end, and the air flow can flow into the downstream cylinder 200 without flowing through the joint, so that the air leakage caused by the fact that the air flow flows through the joint of the upstream cylinder 100 and the downstream cylinder 200 is effectively reduced, the air quantity at the tail end of the air duct is correspondingly improved, and the air supplementing and air exchanging effects of the air duct on a tunneling working surface are ensured.

When the dryer needs to be carried or stored, the connection between the upstream connecting end and the downstream connecting end can be disassembled, and then the upstream cylinder 100 and the downstream cylinder 200 are carried or stored, so that the use convenience of the dryer is improved.

In this embodiment, the upstream cylinder 100, the downstream cylinder 200, and the annular skirt cylinder 300 may each be flexible cylinders. When the air duct needs to be used, the upstream connecting end of the upstream cylinder 100 is connected with the downstream connecting end of the downstream cylinder 200, the air outlet end 310 of the annular skirt cylinder 300 is located in the downstream cylinder 200, when air flows into the annular skirt cylinder 300 through the upstream cylinder 100, the upstream cylinder 100 and the annular skirt cylinder 300 can be supported, the annular skirt cylinder 300 is blown to extend towards the downstream cylinder 200 along the axial direction, then the air flows into the downstream cylinder 200 and supports the downstream cylinder 200, and therefore the air guiding effect of the air duct is achieved, in the air guiding process, the annular skirt cylinder 300 can effectively block the connecting position of the upstream cylinder 100 and the downstream cylinder 200, the air tightness of the air duct is improved, the air leakage rate of the connecting position of the upstream cylinder 100 and the downstream cylinder 200 is correspondingly reduced, and the air volume at the tail end of the air duct is improved; in addition, compared with a rigid cylinder, the air duct formed by the flexible cylinder can be bent in the length direction, so that the applicability of the air duct is improved, and the requirements of the air duct on the field environment are reduced. When the air duct is not needed, the flexible upstream cylinder 100, the flexible downstream cylinder 200 and the flexible annular skirt cylinder 300 can be folded to reduce the length and the volume of the air duct, so that the air duct is convenient to store and transport and the like; of course, the connection between the upstream cylinder 100 and the downstream cylinder 200 may be disconnected, and then the upper cylinder and the downstream cylinder 200 may be folded and stored.

In this embodiment, the annular skirt 300 may be a truncated cone, a reduced end of the annular skirt 300 is coaxially connected to the upstream cylinder 100, and a flared end of the annular skirt 300 serves as the air outlet end 310. In this embodiment, the annular skirt 300 has a reduced end approximately equal to the diameter of the upstream cylinder 100, and the reduced end is coaxially connected to the upstream cylinder 100 in the circumferential direction; the diameter of the flared end of the annular skirt 300 is greater than the diameter of the downstream barrel 200; when the upstream cylinder 100 is coaxially connected with the downstream cylinder 200, the flared end of the annular skirt 300 extends into the downstream cylinder 200, and the annular skirt 300 can be supported in the process that the airflow flows through the annular skirt 300, because the diameter of the flared end of the annular skirt 300 is larger than that of the downstream cylinder 200, the flared end can be fully attached to the inner wall of the downstream cylinder 200 under the action of airflow blowing, so that the attachment sealing property of the annular skirt 300 and the downstream cylinder 200 is improved in the air guiding process of the air duct, the air leakage rate caused by the fact that the airflow flows to the joint of the upstream cylinder 100 and the downstream cylinder 200 through the gap between the flared end and the downstream cylinder 200 is correspondingly reduced, the air tightness of the air duct is further improved, and the air volume at the tail end of the air duct is correspondingly further ensured.

In this embodiment, as shown in fig. 1 and fig. 2, the upstream connection end may be connected to the first connection ring 400, the downstream connection end is connected to the second connection ring 500, one of the first connection ring 400 and the second connection ring 500 is a first magnetic ring, the other is a second magnetic ring or an iron ring, and the first connection ring 400 and the second connection ring 500 are magnetically connected. Here, a specific form of detachably and fixedly connecting the upstream connection end and the downstream connection end is adopted, when the upstream cylinder 100 and the downstream cylinder 200 need to be connected, the annular skirt 300 can be inserted into the downstream cylinder 200, and the first connection ring 400 and the second connection ring 500 are aligned and magnetically attracted together, so that the connection between the upstream connection end and the downstream connection end is realized, and the connection between the upstream cylinder 100 and the downstream cylinder 200 is completed; when the upstream cylinder 100 and the downstream cylinder 200 need to be disassembled, the first connecting ring 400 and the second connecting ring 500 are separated by force, so that the disassembling and assembling convenience of the upstream cylinder 100 and the downstream cylinder 200 is greatly improved, and the using convenience of the cylinders is correspondingly improved. Specifically, the first connection ring 400 and the second connection ring 500 may both take the form of magnetic rings, and the two magnetic rings attract each other; or, the first connection ring 400 is in the form of a magnetic ring, the second connection ring 500 is in the form of an iron ring, and the magnetic ring and the iron ring attract each other.

Specifically, the magnetic ring can be a permanent magnet or an electromagnet; when the first magnetic ring is an electromagnet and needs to be connected with the first connecting ring 400 and the second connecting ring 500, the first magnetic ring can be connected, and the first magnetic ring generates magnetic force to be magnetically attracted with the second connecting ring 500; when the upstream cylinder 100 and the downstream cylinder 200 need to be disassembled, the first magnetic ring is powered off, the first magnetic ring no longer has magnetic force, the first connecting ring 400 and the second connecting ring 500 are not attracted any more, and the two are naturally disconnected, so that the convenience in disassembling and assembling the upstream cylinder 100 and the downstream cylinder 200 is further improved.

In this embodiment, as shown in fig. 2, the air duct connecting structure may include an integral barrel, the first connecting ring 400 is enclosed on the outer wall of the integral barrel, along the axial direction of the integral barrel, the upstream barrel 100 is formed by the barrel section on one side of the first connecting ring 400, and the annular skirt 300 is formed by the barrel section on the other side of the first connecting ring 400. The upstream cylinder 100 and the annular skirt cylinder 300 are integrally formed, when the upstream cylinder 100 and the annular skirt cylinder 300 are connected, the air outlet end 310 of the annular skirt cylinder 300 extends into the downstream cylinder 200, then the first connecting ring 400 and the second connecting ring 500 are connected in a magnetic attraction mode, the cylinder diameter of the annular skirt cylinder 300 is approximately equal to that of the downstream cylinder 200, when an air duct conducts air, the annular skirt cylinder 300 is supported by air flow, the fitting degree of the outer wall of the annular skirt cylinder 300 and the inner wall of the downstream skirt cylinder is high, accordingly, the connection sealing performance of the annular skirt cylinder 300 and the downstream cylinder 200 can be guaranteed, and therefore the air tightness of the air duct is further improved. In addition, the upstream end of the annular skirt cylinder 300 and the downstream end of the upstream cylinder 100 are integrally formed, and the connection sealing performance of the upstream end and the downstream end is higher, so that the occurrence of air leakage at the joint of the annular skirt cylinder 300 and the upstream cylinder 100 is effectively reduced, and the air tightness of the air duct is correspondingly further improved; in addition, the annular skirt cylinder 300 and the upstream cylinder 100 are integrally formed, and during machining, the annular skirt cylinder 300 and the upstream cylinder 100 do not need to be connected, so that machining convenience of the air duct is improved, and machining cost is correspondingly reduced.

In this embodiment, a first locking member may be provided at the upstream cylinder 100 and a second locking member may be provided at the downstream cylinder 200, the first locking member being detachably coupled to the second locking member. After the upstream connection ring of the upstream cylinder 100 and the downstream connection ring of the downstream cylinder 200 are magnetically connected, the first locking member and the second locking member may be connected to perform a secondary connection between the upstream cylinder 100 and the downstream cylinder 200, the connection position of the first locking member and the upstream cylinder 100 is set to be a first connection position, the connection position of the second locking member and the downstream cylinder 200 is set to be a second connection position, the length of the first connection position from the first connection ring 400 is a, the length of the second connection position from the second connection ring 500 is b, the length of the first locking member and the second locking member between the first connection position and the second connection position after the connection between the first locking member and the second locking member is c, c is equal to or less than the sum of a and b, and when the upstream cylinder 100 and the downstream cylinder 200 are subjected to a tensile force in a direction deviating from each other, the connection between the first locking member and the second locking member can overcome the tensile force to ensure the connection between the first connection ring 400 and the second connection ring 500, the connection firmness of the upstream cylinder 100 and the downstream cylinder 200 is correspondingly improved, and the situation that the first connecting ring 400 is separated from the second connecting ring 500 when the air duct is dragged is reduced.

Specifically, in the present embodiment, as shown in fig. 1 and 2, one of the first locking member and the second locking member is the fastening band 600, the other one is the fastening buckle 700, the fastening band 600 is provided with a plurality of fastening holes 610, and the plurality of fastening holes 610 are arranged at intervals along the length direction of the fastening band 600; the tie-down buckle 700 includes a buckle 710, the buckle 710 having a cross arm 720 attached thereto, the cross arm 720 dividing the interior of the buckle 710 into a first ring 740 and a second ring 750, the cross arm 720 having a locking arm 730 hinged thereto; the cross arm 720 is connected to one of the upstream and

downstream cartridges

100 and 200, one end of the tightening band 600 is connected to the other of the upstream and

downstream cartridges

100 and 200, the other end of the tightening band 600 sequentially passes through the first ring 740 and the second ring 750, and the locking arm 730 is inserted into one of the tightening holes 610. Here, a specific form of the first locking member and the second locking member, a binding band 600 having a certain length is sequentially passed through the first ring body 740 and the second ring body 750, and the locking arm 730 of the cross arm 720 is passed through one of the binding holes 610, thereby achieving the connection of the binding band 600 with the binding buckle 700; when it is necessary to detach the fastening band 600 from the fastening buckle 700, the locking arm 730 is pulled out of the fastening hole 610, and then the fastening band 600 is pulled out of the buckle 710. Wherein, set up a plurality of holes 610 of tightening on tightening band 600, can insert locking arm 730 in the hole 610 of tightening of suitable position according to the length of a and b, to both fixed position precision when correspondingly can reduce fixed tightening band 600 and tightening buckle 700 to improve tightening band 600 and the installation convenience of tightening buckle 700.

Of course, in other embodiments, the first locking member and the second locking member may take other forms, such as a hook and loop type fastening member, a snap type fastening member, or the like. Preferably, the first locking member may be a plurality of first locking members, and the plurality of first locking members are uniformly spaced along the circumferential direction of the upstream cylinder 100; the second retaining member also is a plurality of, and a plurality of second retaining members are arranged along the even interval of circumference of low reaches barrel 200, and a plurality of second retaining members and a plurality of first retaining member one-to-one.

Alternatively, in this embodiment, as shown in fig. 3, one of two opposite end surfaces of the first connection ring 400 and the second connection ring 500 may be provided with a limiting groove 410, and the other end surface is provided with a limiting boss 510, and when the first connection ring 400 and the second connection ring 500 are magnetically connected, the limiting boss 510 is inserted into the limiting groove 410 in a matching manner. When the upstream cylinder 100 is connected to the downstream cylinder 200, the first connection ring 400 and the second connection ring 500 are coaxially aligned, the limit boss 510 is aligned with the limit groove 410, the first connection ring 400 and the second connection ring 500 are moved in opposite directions and magnetically connected, and the limit boss 510 is inserted into the limit groove 410, so that the connection between the upstream cylinder 100 and the downstream cylinder 200 is realized. The limiting bosses 510 and the limiting grooves 410 are arranged to limit the circumferential positions of the first connecting ring 400 connected with the second connecting ring 500, so as to ensure that the positions of the first locking member correspond to those of the second locking member, and accordingly ensure the connection between the first locking member and the second locking member; on the other hand, the connection area between the first connection ring 400 and the second connection ring 500 can be increased, the magnetic attraction acting force between the first connection ring and the second connection ring is correspondingly increased, and the connection firmness between the first connection ring and the second connection ring is improved. Specifically, the limiting boss 510 and the limiting groove 410 may be annular structures, or may be a plurality of arc structures arranged at intervals along the circumferential direction of the corresponding connecting ring.

The embodiment also provides an air duct, including the barrel that the multistage connects gradually, above-mentioned air duct connection structure is all adopted to the multistage barrel, along the air current direction in the air duct, in two sections adjacent barrels, the barrel that is located the upper reaches is as the upstream barrel 100 in the air duct connection structure, and the barrel that is located the low reaches is as the low reaches barrel 200 in the air duct connection structure. The air duct is formed by sequentially connecting a plurality of sections of ducts, in every two adjacent ducts along the air guide direction in the air duct, the duct positioned at the upstream can be used as an upstream duct 100, the duct positioned at the downstream can be used as a downstream duct 200, and the upstream duct 100 and the downstream duct 200 can be connected by adopting the air duct connecting structure, namely, an annular skirt duct 300 is arranged in the upstream duct 100, and the upstream connecting end of the upstream duct 100 is detachably connected with the downstream connecting end of the downstream duct 200; when the dryer is ventilated, the air current blows to the downstream barrel 200 from the upstream barrel 100, and the annular skirt 300 can separate the junction of the upstream barrel 100 and the downstream barrel 200, so that the air current can directly blow into the downstream barrel 200 through the annular skirt 300, thereby reducing the air leakage at the junction of the upstream barrel 100 and the downstream barrel 200 and correspondingly improving the air quantity at the tail end of the dryer.

Specifically, in this embodiment, the multiple sections of cylinders are all the same. Along the wind guide direction of the wind barrel, except for a head end barrel and a tail end barrel, any other barrel can be used as a downstream barrel 200 when connected with an upstream adjacent barrel, and can be used as an upstream barrel 100 when connected with a downstream adjacent barrel, so that one end of any barrel positioned at the upstream is a downstream connecting end, one end positioned at the downstream is an upstream connecting end, the end of each barrel close to the upstream connecting end is connected with an annular skirt barrel 300, each barrel is set to be in the same form and specification, and a plurality of barrels can be connected without distinguishing the sequence of the barrels during connection, so that the assembly convenience of the wind barrel is improved; in addition, can carry out batch production to the barrel during processing, the convenient degree of processing of corresponding improvement barrel reduces its processing cost.

Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The air duct connecting structure is characterized by comprising an upstream barrel (100) and a downstream barrel (200), wherein the upstream connecting end of the upstream barrel (100) is detachably connected with the downstream connecting end of the downstream barrel (200); the upstream cylinder (100) is connected with an annular skirt cylinder (300), and when the air duct conducts air, the air outlet end (310) of the annular skirt cylinder (300) is inserted into the downstream cylinder (200).

2. The air duct connecting structure according to claim 1, wherein the upstream cylinder (100), the downstream cylinder (200) and the annular skirt cylinder (300) are all flexible cylinders.

3. The air duct connecting structure according to claim 2, wherein the annular skirt (300) is a truncated cone, a reduced end of the annular skirt (300) is coaxially connected with the upstream cylinder (100), and a flared end of the annular skirt (300) serves as the air outlet end (310).

4. The air duct connecting structure according to claim 1 or 2, wherein the upstream connecting end is connected with a first connecting ring (400), the downstream connecting end is connected with a second connecting ring (500), one of the first connecting ring (400) and the second connecting ring (500) is a first magnetic ring, the other one of the first connecting ring and the second connecting ring is a second magnetic ring or an iron ring, and the first connecting ring (400) and the second connecting ring (500) are magnetically connected.

5. The air duct connecting structure according to claim 4, characterized in that the air duct connecting structure comprises an integral cylinder, the first connecting ring (400) is enclosed on the outer wall of the integral cylinder, in the axial direction of the integral cylinder, a cylinder section on one side of the first connecting ring (400) forms the upstream cylinder (100), and a cylinder section on the other side of the first connecting ring (400) forms the annular skirt cylinder (300).

6. The air duct connecting structure according to claim 4, characterized in that the upstream cylinder (100) is provided with a first locking member, and the downstream cylinder (200) is provided with a second locking member, and the first locking member is detachably connected with the second locking member.

7. The air duct connecting structure according to claim 6, wherein one of the first locking member and the second locking member is a fastening band (600), the other one is a fastening buckle (700), the fastening band (600) is provided with a plurality of fastening holes (610), and the plurality of fastening holes (610) are arranged at intervals along the length direction of the fastening band (600);

the tightening buckle (700) comprises a buckle ring (710), a cross arm (720) is connected to the buckle ring (710), the cross arm (720) divides the ring of the buckle ring (710) into a first ring body (740) and a second ring body (750), and the cross arm (720) is hinged with a locking arm (730); the cross arm (720) is connected to one of the upstream cylinder (100) and the downstream cylinder (200), one end of the tightening belt (600) is connected to the other of the upstream cylinder (100) and the downstream cylinder (200), the other end of the tightening belt (600) sequentially penetrates through the first ring body (740) and the second ring body (750), and the locking arm (730) is inserted into one of the tightening holes (610).

8. The air duct connecting structure according to claim 4, wherein one of two opposite end surfaces of the first connecting ring (400) and the second connecting ring (500) is provided with a limiting groove (410), the other end surface is provided with a limiting boss (510), and when the first connecting ring (400) and the second connecting ring (500) are magnetically connected, the limiting boss (510) is inserted into the limiting groove (410) in a matching manner.

9. An air duct, characterized by comprising a plurality of sections of sequentially connected cylinders, wherein the plurality of sections of cylinders all adopt the air duct connecting structure of any one of claims 1 to 8, and in the direction of air flow in the air duct, the upstream cylinder in the two adjacent sections of cylinders is used as the upstream cylinder (100) in the air duct connecting structure, and the downstream cylinder in the two adjacent sections of cylinders is used as the downstream cylinder (200) in the air duct connecting structure.

10. The air duct of claim 9, wherein the plurality of sections of the barrel are all identical.