Underground section adjusting type air door

Abstract

The underground section adjusting type air door comprises a door frame, a first air door body and a second air door body, the first air door body and the second air door body are hinged to the door frame and located on the left side and the right side of the door frame respectively, and the side, close to the second air door body, of the first air door body is slidably connected with a first sliding plate; a first sliding groove matched with the first sliding plate is formed in the side wall of the first air door, the first sliding plate is located in the first sliding groove, a first driving assembly is installed in the first sliding groove, and the first driving assembly is used for pushing the first sliding plate to move in the first sliding groove. The invention aims to provide an underground section adjustable air door to solve the problem that the ventilation quantity of an air door with a fixed section is difficult to adjust flexibly when the underground ventilation requirement is changed due to mining stage change, roadway layout adjustment or local ventilation requirement change in the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of mine ventilation, and in particular to an underground cross-section adjustable damper. Background Art

[0002] In mining operations, the underground ventilation system plays a vital role. It not only provides the necessary fresh air for miners, but also effectively removes harmful gases and dust to ensure the air quality in the mine and the health of miners.

[0003] In the traditional underground ventilation system, the air in the mine is regulated by opening and closing dampers, most of which are fixed-section structures. When the underground ventilation demand changes due to changes in the mining stage, tunnel layout adjustment or local ventilation requirements, it is difficult for the fixed-section dampers to flexibly adjust the ventilation volume. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide an underground cross-section adjustable damper to solve the problem in the prior art that the damper with a fixed cross-section is difficult to flexibly adjust the ventilation volume when the underground ventilation demand changes due to changes in the mining stage, adjustment of the tunnel layout or changes in local ventilation requirements.

[0005] The present invention is achieved through the following technical solutions:

[0006] A downhole cross-section adjustable damper comprises a door frame and a first damper and a second damper hinged on the door frame, wherein the first damper and the second damper are respectively located on the left and right sides of the door frame, a first slide plate is slidably connected to a side of the first damper close to the second damper, a first slide groove matched with the first slide plate is provided on the side wall of the first damper, the first slide plate is located in the first slide groove, a first drive assembly is installed in the first slide groove, and the first drive assembly is used to push the first slide plate to move in the first slide groove.

[0007] Furthermore, the first driving assembly includes a first cylinder fixedly mounted on the side wall of the first slide groove, the output end of the first cylinder is fixedly connected to the side wall of the first slide plate, the first cylinder is connected to a first air pipe, and a first pressure relief valve is installed on the first air pipe.

[0008] Furthermore, a second slide plate is slidably connected to a side of the second damper close to the first damper, a second slide groove matched with the second slide plate is opened on the side wall of the second damper, the second slide plate is located in the second slide groove, a second cylinder is fixedly installed on the side wall of the second slide groove, an output end of the second cylinder is fixedly connected to the side wall of the second slide plate, the second cylinder is connected to a second air pipe, and a second pressure relief valve is installed on the second air pipe.

[0009] Furthermore, a boss is fixedly connected to the first slide plate, and a groove matched with the boss is fixedly connected to the second slide plate, and the boss is clamped in the groove.

[0010] Furthermore, a mounting groove is formed on the boss, and a distance sensor is installed in the mounting groove. The distance sensor is used to detect the distance between the first slide plate and the second slide plate.

[0011] Furthermore, handles are fixedly connected to the side walls of the first slide plate and the second slide plate, and when the first damper and the second damper are closed, the plurality of handles are close to the central axis of the door frame.

[0012] Furthermore, both the first slide plate and the second slide plate are provided with observation windows, and transparent glass is fixedly connected inside the observation windows.

[0013] Furthermore, seals are fixedly connected to the side walls of the first damper and the second damper, and the seals are fitted to the door frame when the first damper and the second damper are closed, and a rubber strip is fixedly connected to one side of the seals that fits the door frame.

[0014] Further, a connecting shaft is provided on the door frame, the connecting shaft is rotatably connected to the door frame, a first bevel gear and a spur gear are fixedly connected to the connecting shaft, and a second bevel gear and a third bevel gear are respectively meshed on both sides of the first bevel gear;

[0015] The second bevel gear is fixedly connected with a first worm, the first worm is transmission-connected with a first worm wheel, and the first damper is provided with a first rotating shaft fixedly connected with the first worm wheel;

[0016] The third bevel gear is connected to a second worm, the second worm is drivingly connected to a second worm wheel 32, and the second damper is provided with a second rotating shaft fixedly connected to the second worm wheel 32;

[0017] The first rotating shaft, the second rotating shaft, the first worm and the second worm are all rotatably connected to the door frame, the first worm and the second worm extend along the length direction of the door frame, and the first rotating shaft and the second rotating shaft extend along the height direction of the door frame;

[0018] A rack is meshed on the spur gear, and the rack is slidably connected to the door frame. Both ends of the rack are fixedly connected to pull ropes, and pulleys are fixedly installed on both sides of the top of the door frame. The two pull ropes are respectively wound around the corresponding pulleys.

[0019] Furthermore, a motor is fixedly mounted on the door frame, and an output shaft of the motor is fixedly connected to the connecting shaft.

[0020] The beneficial effects of the present invention are:

[0021] This kind of underground cross-section adjustable damper, when the first damper and the second damper need to be closed, the first damper is rotated clockwise and the second damper is rotated counterclockwise, so that the first damper and the second damper fit the door frame, and the first slide is pushed by the driving component to slide in the first slide slot and protrude the first damper so that it is against the second damper. When the first damper and the second damper need to be opened, the first damper is rotated counterclockwise and the second damper is rotated clockwise, so that one side of the first damper and the second damper is away from the door frame. When a certain amount of ventilation is required, the first slide is pushed by the driving component to slide to a suitable position in the first slide slot or the first damper and the second damper are turned to a suitable angle. Compared with the prior art, when the underground ventilation demand changes due to changes in the mining stage, the adjustment of the tunnel layout or the change of local ventilation requirements, the damper with a fixed cross section can adjust the ventilation volume more flexibly.

[0022] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The three-dimensional Figure 1 ;

[0024] Figure 2 The three-dimensional Figure 2 ;

[0025] Figure 3 It is a structural schematic diagram of the present invention;

[0026] Figure 4 It is a schematic diagram of the local structure of the present invention Figure 1 ;

[0027] Figure 5 It is a schematic diagram of the local structure of the present invention Figure 2 ;

[0028] Figure 6 It is a schematic diagram of the local structure of the present invention Figure 3 ;

[0029] Figure 7 It is a schematic diagram of the connection between the seal and the rubber strip of the present invention.

[0030] In the figure:

[0031] 1. Door frame; 2. First damper; 3. Second damper; 4. First slide plate; 5. First slide groove; 6. First cylinder; 7. First air pipe; 8. First pressure relief valve; 9. Second slide plate; 10. Second slide groove; 11. Second cylinder; 12. Second air pipe; 13. Second pressure relief valve; 14. Boss; 15. Groove; 16. Mounting groove; 17. Distance sensor; 18. Handle; 19. Observation window; 20. Transparent glass; 21. Seal; 22. Rubber strip; 23. Connecting shaft; 24. First bevel gear; 25. Spur gear; 26. Second bevel gear; 27. Third bevel gear; 28. First worm; 29. ​​First worm wheel; 30. First rotating shaft; 31. Second worm; 32. Second worm wheel 32; 33. Second rotating shaft; 34. Rack; 35. Pull rope; 36. Pulley; 37. Motor. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0035] In the above description of the present invention, it should be noted that the terms "one side", "the other side", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0036] In addition, the term "same" does not mean that the parts must be absolutely the same, but slight differences are allowed. The term "vertical" only means that the positional relationship between the parts is more vertical than "parallel", and does not mean that the structure must be completely vertical, but can be slightly tilted.

[0037] See also Figure 1-7 The present invention provides a technical solution: an underground cross-section adjustable damper, comprising a door frame 1 and a first damper 2 and a second damper 3 hinged on the door frame 1, wherein the first damper 2 and the second damper 3 are respectively located on the left and right sides of the door frame 1, and a first slide plate 4 is slidably connected to a side of the first damper 2 close to the second damper 3, and a first slide groove 5 adapted to the first slide plate 4 is provided on the side wall of the first damper 2, the first slide plate 4 is located in the first slide groove 5, and a first driving component is installed in the first slide groove 5, and the first driving component is used to push the first slide plate 4 to move in the first slide groove 5.

[0038] In this solution, rotating the first damper 2 clockwise and the second damper 3 counterclockwise can close the first damper 2 and the second damper 3, and rotating the first damper 2 counterclockwise and the second damper 3 clockwise can open the first damper 2 and the second damper 3.

[0039] When the first damper 2 and the second damper 3 need to be closed, the first damper 2 is rotated clockwise and the second damper 3 is rotated counterclockwise so that the first damper 2 and the second damper 3 fit the door frame 1, and the first slide plate 4 is pushed by the driving assembly to slide in the first slide groove 5 and protrude the first damper 2 so that it is against the second damper 3.

[0040] When the first damper 2 and the second damper 3 need to be opened, the first damper 2 and the second damper 3 are rotated counterclockwise and clockwise, so that one side of the first damper 2 and the second damper 3 are away from the door frame 1 .

[0041] When a certain ventilation is required, the first slide plate 4 is pushed by the driving assembly to slide to a suitable position in the first slide slot 5 or the first damper 2 and the second damper 3 are turned to a suitable angle.

[0042] Compared with the existing technology, the fixed-section dampers can adjust the ventilation volume more flexibly when the underground ventilation demand changes due to changes in the mining stage, tunnel layout adjustment or local ventilation requirements.

[0043] In this embodiment: the first driving assembly includes a first cylinder 6 fixedly mounted on the side wall of the first slide groove 5, the output end of the first cylinder 6 is fixedly connected to the side wall of the first slide plate 4, the first cylinder 6 is connected to a first air pipe 7, and the first air pipe 7 is installed with a first pressure relief valve 8.

[0044] In this solution: the first cylinder 6 is electrically connected to a controller. When a certain ventilation is required, the controller controls the first cylinder 6 to push the first slide plate 4 so that it slides to a suitable position in the first slide groove 5 to achieve the ventilation effect.

[0045] In an emergency, the first pressure relief valve 8 can be opened and the first slide plate 4 can be manually pushed to provide a convenient escape passage for the staff.

[0046] In this embodiment: the second damper 3 is slidably connected to a second slide plate 9 on one side close to the first damper 2, a second slide groove 10 matched with the second slide plate 9 is opened on the side wall of the second damper 3, the second slide plate 9 is located in the second slide groove 10, a second cylinder 11 is fixedly installed on the side wall of the second slide groove 10, the output end of the second cylinder 11 is fixedly connected to the side wall of the second slide plate 9, the second cylinder 11 is connected to a second air pipe 12, and a second pressure relief valve 13 is installed on the second air pipe 12.

[0047] In this solution: a second slide plate 9 is slidably connected to the side of the second damper 3 close to the first damper 2, a second slide groove 10 adapted to the second slide plate 9 is provided on the side wall of the second damper 3, the second slide plate 9 is located in the second slide groove 10, a second cylinder 11 is fixedly installed on the side wall of the second slide groove 10, the output end of the second cylinder 11 is fixedly connected to the side wall of the second slide plate 9, the second cylinder 11 is connected to the second air supply pipe 12, and a second pressure relief valve 13 is installed on the second air supply pipe 12. The second cylinder 11 is electrically connected to the controller.

[0048] When a certain ventilation is required, the controller controls the second cylinder 11 to push the second slide plate 9 so that it slides to a suitable position in the second slide groove 10 to achieve the ventilation effect. It is further adapted to mines of different widths.

[0049] In an emergency, the second pressure relief valve 13 can be opened and the second slide plate 9 can be manually pushed to provide a convenient escape passage for the staff.

[0050] In this embodiment: a boss 14 is fixedly connected to the first slide plate 4 , a groove 15 matched with the boss 14 is fixedly connected to the second slide plate 9 , and the boss 14 is snap-fitted into the groove 15 .

[0051] In this solution, the boss 14 is fixedly connected to the first slide plate 4, and the groove 15 matched with the boss 14 is fixedly connected to the second slide plate 9, and the boss 14 is clamped in the groove 15. The sealing between the first slide plate 4 and the second slide plate 9 is improved, and the stability of the connection between the first slide plate 4 and the second slide plate 9 is also improved.

[0052] In this embodiment, a mounting groove 16 is formed on the boss 14 , and a distance sensor 17 is installed in the mounting groove 16 . The distance sensor 17 is used to detect the distance between the first slide plate 4 and the second slide plate 9 .

[0053] In this solution, a mounting groove 16 is provided on the boss 14, and a distance sensor 17 is installed in the mounting groove 16. The distance sensor 17 is used to detect the distance between the first slide plate 4 and the second slide plate 9. The distance sensor 17 is electrically connected to the controller, and the distance sensor 17 is controlled by the controller to detect the distance between the first slide plate 4 and the second slide plate 9, so that the distance between the first slide plate 4 and the second slide plate 9 can be accurately adjusted.

[0054] In this embodiment: handles 18 are fixedly connected to the side walls of the first slide plate 4 and the second slide plate 9 . When the first damper 2 and the second damper 3 are closed, the plurality of handles 18 are close to the central axis of the door frame 1 .

[0055] In this solution, the handles 18 are fixedly connected to the side walls of the first slide plate 4 and the second slide plate 9. When the first damper 2 and the second damper 3 are closed, the handles 18 are close to the central axis of the door frame 1, so that the staff can push the first slide plate 4 and the second slide plate 9 conveniently.

[0056] In this embodiment, both the first slide plate 4 and the second slide plate 9 are provided with an observation window 19 , and a transparent glass 20 is fixedly connected inside the observation window 19 .

[0057] In this solution, an observation window 19 is provided on both the first slide plate 4 and the second slide plate 9, and a transparent glass 20 is fixedly connected in the observation window 19. It is convenient for the staff to observe the situation on the other side when the first damper 2 or the second damper 3 is not opened.

[0058] In this embodiment: a seal 21 is fixedly connected to the side walls of the first damper 2 and the second damper 3. The seal 21 fits with the door frame 1 when the first damper 2 and the second damper 3 are closed. A rubber strip 22 is fixedly connected to one side of the seal 21 that fits the door frame 1.

[0059] In this solution, the sealing strip 21 is fixedly connected to the side walls of the first damper 2 and the second damper 3, and the sealing strip 21 is attached to the door frame 1 when the first damper 2 and the second damper 3 are closed, and the sealing strip 21 is fixedly connected to the rubber strip 22 on one side of the door frame 1. The sealing between the first damper 2 and the second damper 3 and the door frame 1 is improved.

[0060] In this embodiment: the door frame 1 is provided with a connecting shaft 23, the connecting shaft 23 is rotatably connected to the door frame 1, the connecting shaft 23 is fixedly connected with a first bevel gear 24 and a spur gear 25, and the first bevel gear 24 is respectively meshed with a second bevel gear 26 and a third bevel gear 27 on both sides;

[0061] The second bevel gear 26 is fixedly connected with a first worm 28, the first worm 28 is drivingly connected with a first worm wheel 29, and the first damper 2 is provided with a first rotating shaft 30 fixedly connected with the first worm wheel 29;

[0062] The third bevel gear 27 is connected to a second worm 31, the second worm 31 is transmission-connected to a second worm wheel 32, and the second damper 3 is provided with a second rotating shaft 33 fixedly connected to the second worm wheel 32;

[0063] The first rotating shaft 30, the second rotating shaft 33, the first worm 28 and the second worm 31 are all rotatably connected to the door frame 1, the first worm 28 and the second worm 31 are both extended along the length direction of the door frame 1, and the first rotating shaft 30 and the second rotating shaft 33 are extended along the height direction of the door frame 1;

[0064] The spur gear 25 is meshed with a rack 34, which is slidably connected to the door frame 1. Both ends of the rack 34 are fixedly connected to pull ropes 35. Pulleys 36 are fixedly installed on both sides of the top of the door frame 1, and the two pull ropes 35 are respectively wound around the corresponding pulleys 36.

[0065] In this solution: when it is necessary to open the first damper 2 and the second damper 3, the pull rope 35 is pulled to move the rack 34 to the right, further driving the spur gear 25 to rotate clockwise, further driving the connecting shaft 23 and the first bevel gear 24 to rotate clockwise, further driving the second bevel gear 26 to rotate counterclockwise and the third bevel gear 27 to rotate clockwise, further driving the first worm 28 to rotate counterclockwise and the second worm 31 to rotate clockwise, further driving the first worm gear 29 to rotate counterclockwise and the second worm gear 32 to rotate clockwise by a certain angle, so that the first damper 2 and the second damper 3 rotate counterclockwise.

[0066] When the first damper 2 and the second damper 3 need to be closed, the pull rope 35 is pulled to move the rack 34 to the left, further driving the spur gear 25 to rotate counterclockwise, further driving the connecting shaft 23 and the first bevel gear 24 to rotate counterclockwise, further driving the second bevel gear 26 to rotate clockwise and the third bevel gear 27 to rotate counterclockwise, further driving the first worm 28 to rotate clockwise and the second worm 31 to rotate counterclockwise, further driving the first worm gear 29 to rotate clockwise and the second worm gear 32 to rotate counterclockwise by a certain angle, so that the first damper 2 rotates clockwise and the second damper 3 rotates counterclockwise. The first damper 2 and the second damper 3 are made to fit the door frame 1, and the first slide plate 4 is pushed by the driving assembly to slide in the first slide slot 5 and protrude the first damper 2 so that it abuts against the second damper 3.

[0067] In this embodiment: a motor 37 is fixedly mounted on the door frame 1 , and an output shaft of the motor 37 is fixedly connected to the connecting shaft 23 .

[0068] In this solution: the motor 37 is electrically connected to the controller. When the first damper 2 and the second damper 3 need to be opened, the controller controls the output shaft of the motor 37 to rotate clockwise, further driving the spur gear 25, the connecting shaft 23 and the first bevel gear 24 to rotate clockwise, further driving the second bevel gear 26 to rotate counterclockwise and the third bevel gear 27 to rotate clockwise, further driving the first worm 28 to rotate counterclockwise and the second worm 31 to rotate clockwise, further driving the first worm gear 29 to rotate counterclockwise and the second worm gear 32 to rotate clockwise by a certain angle, so that the first damper 2 rotates counterclockwise and the second damper 3 rotates clockwise.

[0069] When the first damper 2 and the second damper 3 need to be closed, the controller controls the output shaft of the motor 37 to rotate counterclockwise, further driving the spur gear 25, the connecting shaft 23 and the first bevel gear 24 to rotate counterclockwise, further driving the second bevel gear 26 to rotate clockwise and the third bevel gear 27 to rotate counterclockwise, further driving the first worm 28 to rotate clockwise and the second worm 31 to rotate counterclockwise, further driving the first worm gear 29 to rotate clockwise and the second worm gear 32 to rotate counterclockwise by a certain angle, so that the first damper 2 and the second damper 3 rotate clockwise and counterclockwise. The first damper 2 and the second damper 3 are made to fit the door frame 1, and the first slide plate 4 is pushed by the driving component to slide in the first slide slot 5 and protrude the first damper 2 so that it abuts against the second damper 3.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. An underground cross-section adjustable damper, comprising a door frame (1) and a first damper (2) and a second damper (3) hinged on the door frame (1), characterized in that: The first damper (2) and the second damper (3) are respectively located on the left and right sides of the door frame (1); a first slide plate (4) is slidably connected to a side of the first damper (2) close to the second damper (3); a first slide groove (5) adapted to the first slide plate (4) is provided on a side wall of the first damper (2); the first slide plate (4) is located in the first slide groove (5); a first driving component is installed in the first slide groove (5); the first driving component is used to push the first slide plate (4) to move in the first slide groove (5).

2. The underground cross-section adjustable damper according to claim 1, characterized in that: The first driving assembly comprises a first cylinder (6) fixedly mounted on a side wall of a first slide groove (5); an output end of the first cylinder (6) is fixedly connected to a side wall of a first slide plate (4); the first cylinder (6) is connected to a first air supply pipe (7); and a first pressure relief valve (8) is mounted on the first air supply pipe (7).

3. The underground cross-section adjustable damper according to claim 1, characterized in that: A second slide plate (9) is slidably connected to a side of the second damper (3) close to the first damper (2); a second slide groove (10) adapted to the second slide plate (9) is provided on a side wall of the second damper (3); the second slide plate (9) is located in the second slide groove (10); a second cylinder (11) is fixedly mounted on the side wall of the second slide groove (10); an output end of the second cylinder (11) is fixedly connected to the side wall of the second slide plate (9); the second cylinder (11) is connected to a second air supply pipe (12); and a second pressure relief valve (13) is mounted on the second air supply pipe (12).

4. The underground cross-section adjustable damper according to claim 3, characterized in that: The first slide plate (4) is fixedly connected with a boss (14), the second slide plate (9) is fixedly connected with a groove (15) matched with the boss (14), and the boss (14) is clamped in the groove (15).

5. The underground cross-section adjustable damper according to claim 4, characterized in that: The boss (14) is provided with a mounting groove (16), a distance sensor (17) is installed in the mounting groove (16), and the distance sensor (17) is used to detect the distance between the first slide plate (4) and the second slide plate (9).

6. The underground cross-section adjustable damper according to claim 3, characterized in that: Handles (18) are fixedly connected to the side walls of the first slide plate (4) and the second slide plate (9); when the first damper (2) and the second damper (3) are closed, the plurality of handles (18) are close to the central axis of the door frame (1).

7. The underground cross-section adjustable damper according to claim 3, characterized in that: The first slide plate (4) and the second slide plate (9) are both provided with an observation window (19), and a transparent glass (20) is fixedly connected inside the observation window (19).

8. The underground cross-section adjustable damper according to claim 1, characterized in that: The side walls of the first damper (2) and the second damper (3) are both fixedly connected with a seal strip (21); the seal strip (21) is in contact with the door frame (1) when the first damper (2) and the second damper (3) are closed; and a rubber strip (22) is fixedly connected to one side of the seal strip (21) that is in contact with the door frame (1).

9. The underground cross-section adjustable damper according to claim 1, characterized in that: The door frame (1) is provided with a connecting shaft (23), the connecting shaft (23) is rotatably connected to the door frame (1), a first bevel gear (24) and a spur gear (25) are fixedly connected to the connecting shaft (23), and a second bevel gear (26) and a third bevel gear (27) are respectively meshed on both sides of the first bevel gear (24); The second bevel gear (26) is fixedly connected to a first worm (28), the first worm (28) is drivingly connected to a first worm wheel (29), and the first damper (2) is provided with a first rotating shaft (30) fixedly connected to the first worm wheel (29); The third bevel gear (27) is connected to a second worm (31), the second worm (31) is transmission-connected to a second worm wheel (32), and the second damper (3) is provided with a second rotating shaft (33) fixedly connected to the second worm wheel (32); The first rotating shaft (30), the second rotating shaft (33), the first worm (28) and the second worm (31) are all rotatably connected to the door frame (1); the first worm (28) and the second worm (31) extend along the length direction of the door frame (1); and the first rotating shaft (30) and the second rotating shaft (33) extend along the height direction of the door frame (1); A rack (34) is meshed on the spur gear (25), and the rack (34) is slidably connected to the door frame (1). Both ends of the rack (34) are fixedly connected to pull ropes (35). Pulleys (36) are fixedly installed on both sides of the top of the door frame (1), and the two pull ropes (35) are respectively wound around corresponding pulleys (36).

10. The underground cross-section adjustable damper according to claim 9, characterized in that: A motor (37) is fixedly mounted on the door frame (1), and an output shaft of the motor (37) is fixedly connected to the connecting shaft (23).

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