Air pressure balancing device

Abstract

The invention relates to the technical field of air pressure balancing, and discloses an air pressure balancing device which comprises a non-rigid container, a filling opening is formed in the top of the non-rigid container, arc-shaped fixing plates are arranged on the outer walls of the two sides of the non-rigid container, and a fixing bolt is arranged between the two arc-shaped fixing plates. Supporting plates are fixedly connected to the outer walls of the arc-shaped fixing plates correspondingly, and sliding rods are slidably connected to the upper ends of the supporting plates correspondingly. After dangerous liquid needing hot liquid filling is filled into the non-rigid container, the connector of the gas conveying pipe at the lower end of the gas pressure tank is screwed with the filling opening, and the ball valve on the gas conveying pipe can be automatically opened through heat generated by the non-rigid container, so that inert gas in the gas pressure tank can enter the non-rigid container; and when the pressure in the non-rigid container is reduced, inert gas is supplemented to keep pressure balance inside and outside the non-rigid container, the strength performance of the packaging container of the non-rigid container is guaranteed, and potential safety hazards are eradicated.

Description

Technical Field

[0001] The present invention relates to the technical field of air pressure balancing, and in particular to an air pressure balancing device. Background Art

[0002] For the transportation of hazardous liquids, liquid-tight or airtight seals must be used according to the hazard classification to ensure that the hazardous goods packaging has no obvious deformation. Once deformation occurs, it will seriously affect its packaging performance and cause danger during transportation. The most common packaging for hazardous liquids is a 250-liter non-rigid container, which has stable performance at normal temperature and pressure.

[0003] For hazardous liquids that require hot liquid filling, if the container is sealed directly after filling, the liquid temperature will drop, and the internal gas will cool down, causing the pressure to drop, causing the container to deform under pressure, seriously affecting the packaging strength and affecting the safety of transportation.

[0004] In view of this, the present invention proposes an air pressure balancing device to solve the above problems existing in the prior art. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an air pressure balancing device.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The air pressure balancing device comprises a non-rigid container, a filling port is arranged on the top of the non-rigid container, arc-shaped fixing plates are arranged on the outer walls on both sides of the non-rigid container, and fixing bolts are arranged between the two arc-shaped fixing plates, the outer walls of the arc-shaped fixing plates are fixedly connected to support plates, and the upper ends of the support plates are slidably connected to sliding rods, an air pressure box is fixedly connected between the outer walls on the opposite sides of the two sliding rods, and the other sides of the sliding rods are fixedly connected to limiting disks, a one-way inflation port is arranged on the outer wall of the top of the air pressure box, and an air supply pipe is arranged at the bottom of the air pressure box, a connector is sealingly and rotatably connected to the bottom end of the air supply pipe, and the connector is screwed and connected to the filling port, an extrusion mechanism is arranged inside the air pressure box, and the air pressure box is filled with nitrogen or other inert gases, a ball valve is arranged inside the air supply pipe, and a gear is arranged at the rotating end of the ball valve, and a driving mechanism is arranged on one side of the gear.

[0008] Furthermore, the driving mechanism includes an arc-shaped cavity, which is arranged in the middle of one of the arc-shaped fixed plates, and the inner wall of the arc-shaped cavity is sealed and slidably connected to two arc-shaped plates, a connecting spring 2 is fixedly connected between the two arc-shaped plates, and an inert gas that expands when heated is filled between each arc-shaped plate and the inner wall of one side of the arc-shaped cavity, a connecting pipe 1 is connected to the space formed between the two arc-shaped plates, and a guide rod is arranged above the arc-shaped cavity.

[0009] Furthermore, a storage box is arranged above the gear, the storage box is fixedly connected to the bottom outer wall of the air pressure box, and a rack 1 is arranged at the bottom of the storage box, the inner wall of the storage box is sealingly and slidably connected to a piston plate 2, and a connecting spring 3 is fixedly connected between the piston plate 2 and the top inner wall of the storage box, the top end of the rack 1 is fixedly connected to the bottom outer wall of the piston plate 2, and the rack 1 is meshed with the gear, and the top end of the connecting pipe 1 passes through the guide rod and is connected to the space above the piston plate 2.

[0010] Furthermore, the extrusion mechanism includes two piston plates 1, the two piston plates 1 are symmetrically sealed and slidably connected to the inside of the air pressure box, and a connecting spring 1 is fixedly connected between the piston plate 1 and the inner wall of the air pressure box, two pairs of blocks are symmetrically arranged between the two piston plates 1, and the connecting spring 1 is in a compressed state.

[0011] Furthermore, the outer wall at the top of the connecting head is fixedly connected to a mounting bracket, and the top of the mounting bracket is slidably connected to a threaded rod, the top of the threaded rod is fixedly connected to a knob, and the bottom of the threaded rod is rotatably connected to a pressing plate 1, the pressing plate 1 is slidably connected to the inner wall of the mounting bracket, and an airbag is arranged between the pressing plate 1 and the top of the connecting head.

[0012] Furthermore, an annular groove is provided above the inner wall of the connector, and a sealing ring is provided inside the annular groove, an annular airbag is provided between the sealing ring and the inner wall of the annular groove, and a connecting pipe 2 is connected between the air inlet end and the air outlet end of the annular airbag.

[0013] Furthermore, a transparent cover is provided below the gear, and the transparent cover is fixedly connected to the outer wall at the top of the connector, and a second pressing plate is slidably connected to the inner wall of the transparent cover.

[0014] Furthermore, a rack 2 is fixedly connected to the outer wall of the top of the second pressing plate, and the rack 2 is meshed with the gear, and a piezochromic material is arranged between the second pressing plate and the inner cover at the bottom of the transparent cover.

[0015] The beneficial effects of the present invention are:

[0016] 1. The present invention provides an air pressure box. After the dangerous liquid that needs hot liquid filling is filled into the non-rigid container, the connector of the air pipe at the lower end of the air pressure box is screwed together with the filling port. The heat generated by the non-rigid container can automatically open the ball valve on the air pipe, so that the inert gas in the air pressure box can enter the non-rigid container. When the internal pressure of the non-rigid container is reduced, the inert gas is replenished to keep the pressure balance inside and outside the non-rigid container, ensure the strength performance of the non-rigid container packaging container, and eliminate safety hazards.

[0017] 2. By arranging the airbag, the annular airbag and the sealing ring, when the connector is screwed together with the filling port, the airbag can be squeezed by pressing the plate, so that the gas inside the airbag can enter the annular airbag. The annular airbag expands after receiving the gas, and can push the sealing ring to fit tightly against the outer wall of the filling port to form a sealing structure, thereby avoiding leakage of the inert gas when it is input into a non-rigid container.

[0018] 3. When the pressure inside and outside the non-rigid container is balanced and cooled, the gear can squeeze the pressure-changing color material in the transparent cover through rack 2 to change its color, so that the staff can clearly perceive that the air pressure of the non-rigid container is balanced and cooled, so as to disassemble the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure of the air pressure balancing device proposed in Example 1;

[0020] Figure 2 A schematic diagram of the cross-sectional structure of the air pressure box of the air pressure balancing device proposed in Example 1;

[0021] Figure 3 A schematic cross-sectional structure diagram of an arc-shaped fixing plate of the air pressure balancing device proposed in Example 1;

[0022] Figure 4 The air pressure balance device proposed in Example 1 Figure 1 A schematic diagram of the structure enlargement in the middle;

[0023] Figure 5 A schematic diagram of the cross-sectional structure of a storage box of the air pressure balancing device proposed in Example 1;

[0024] Figure 6 This is a schematic diagram of the top structure of the connector of the air pressure balancing device proposed in Example 2;

[0025] Figure 7 A schematic diagram of the cross-sectional structure of the connector of the air pressure balancing device proposed in Example 2;

[0026] Figure 8 This is a schematic diagram of the connector structure of the air pressure balancing device proposed in Example 3.

[0027] In the figure: 1, non-rigid container; 2, arc-shaped fixing plate; 3, support plate; 4, limit plate; 5, slide rod; 6, air pressure box; 7, guide rod; 8, connecting pipe 1; 9, connector; 10, fixing bolt; 11, filling port; 12, air delivery pipe; 13, piston plate 1; 14, connecting spring 1; 15, one-way inflation port; 16, stopper; 17, arc-shaped cavity; 18, arc-shaped plate; 19, connecting spring 2; 20. Ball valve; 21. Storage box; 22. Rack 1; 23. Gear; 24. Piston plate 2; 25. Connecting spring 3; 26. Air bag; 27. Pressing plate 1; 28. Mounting frame; 29. ​​Threaded rod; 30. Knob; 31. Annular air bag; 32. Annular groove; 33. Connecting pipe 2; 34. Sealing ring; 35. Rack 2; 36. Transparent cover; 37. Pressing plate 2; 38. Pressure-changing material. DETAILED DESCRIPTION

[0028] The technical solution of the present invention is further described in detail below in conjunction with specific implementation methods.

[0029] Example 1: Reference Figure 1-Figure 5The air pressure balancing device comprises a non-rigid container 1, a filling port 11 is arranged on the top of the non-rigid container 1, arc-shaped fixing plates 2 are arranged on the outer walls on both sides of the non-rigid container 1, and fixing bolts 10 are arranged between the two arc-shaped fixing plates 2, the outer walls of the arc-shaped fixing plates 2 are fixedly connected with support plates 3, and the upper ends of the support plates 3 are slidably connected with slide bars 5, an air pressure box 6 is fixedly connected between the outer walls on the opposite sides of the two slide bars 5, and the other sides of the slide bars 5 are fixedly connected with a limiting disk 4, and a one-way filling is arranged on the outer wall of the top of the air pressure box 6 The air port 15 is provided, and the bottom of the air pressure box 6 is provided with an air delivery pipe 12, the bottom end of the air delivery pipe 12 is sealed and rotatably connected with a connector 9, and the connector 9 is screwed and connected with the filling port 11, an extrusion mechanism is provided inside the air pressure box 6, and the air pressure box 6 is filled with nitrogen or other inert gases, a ball valve 20 is provided inside the air delivery pipe 12, and a gear 23 is provided at the rotating end of the ball valve 20, and a driving mechanism is provided on one side of the gear 23. When the dangerous liquid that needs hot liquid filling is filled into the non-rigid container 1, the support plate 3 is moved on the slide rod 5, slide on the upper part to adjust the distance between the two arc-shaped fixing plates 2, and the two arc-shaped fixing plates 2 can be sleeved on the outer wall above the non-rigid container 1, and then the two arc-shaped fixing plates 2 are fixed by fixing bolts 10 to fix them on the non-rigid container 1, and then the position of the air pressure box 6 is adjusted by the sliding rod 5, so that the connector 9 at the bottom end of the air pipe 12 below it is screwed with the filling port 11. Because the dangerous liquid enters the non-rigid container 1 by hot liquid filling, the dangerous liquid will cause the non-rigid container 1 to generate a large amount of heat during the cooling process. The heat can make the driving mechanism run, and the driving mechanism opens the closed ball valve 20 through the gear 23, so that under the action of the squeezing mechanism inside the air pressure box 6, the nitrogen or other inert gas stored in the air pressure box 6 enters the non-rigid container 1 through the air pipe 12, and the inert gas is supplemented when the internal pressure of the non-rigid container 1 is reduced, so as to keep the internal and external pressures of the non-rigid container 1 balanced, ensure the strength performance of the non-rigid container 1 packaging container, and eliminate safety hazards.

[0030] As a further solution in the present invention, the driving mechanism includes an arc-shaped cavity 17, which is arranged in the middle of one of the arc-shaped fixed plates 2, and the inner wall of the arc-shaped cavity 17 is sealed and slidably connected to two arc-shaped plates 18, a connecting spring 2 19 is fixedly connected between the two arc-shaped plates 18, and each arc-shaped plate 18 and the inner wall of one side of the arc-shaped cavity 17 are filled with an inert gas that expands when heated, the space formed between the two arc-shaped plates 18 is connected with a connecting pipe 1 8, and a guide rod 7 is arranged above the arc-shaped cavity 17. The hazardous liquid inside the non-rigid container 1 will generate heat when cooled. When the inert gas filled between the arc-shaped plate 18 and the inner wall of one side of the arc-shaped cavity 17 expands after encountering heat, the two arc-shaped plates 18 can compress the connecting spring 2 19 and move, so that the gas stored between the two arc-shaped plates 18 is squeezed into the connecting pipe 1 8.

[0031] As a further solution in the present invention, a storage box 21 is arranged above the gear 23, and the storage box 21 is fixedly connected to the bottom outer wall of the air pressure box 6, and a rack 22 is arranged at the bottom of the storage box 21, and a piston plate 24 is sealingly and slidably connected to the inner wall of the storage box 21, and a connecting spring 3 25 is fixedly connected between the piston plate 24 and the top inner wall of the storage box 21, and the top of the rack 22 is fixedly connected to the bottom outer wall of the piston plate 24, and the rack 22 is meshed with the gear 23, and the top of the connecting pipe 8 passes through the guide rod 7 and is connected to the space above the piston plate 24, and the gas in the connecting pipe 8 will enter the space formed between the piston plate 24 and the top inner wall of the storage box 21, as more and more gas enters, the piston plate 24 can move downward with the rack 22, and the rack 22 is meshed with the gear 23, so that the gear 23 rotates, and the closed ball valve 20 can be opened.

[0032] As a further solution in the present invention, the extrusion mechanism includes two piston plates 13, and the two piston plates 13 are symmetrically sealed and slidably connected to the inside of the air pressure box 6, and a connecting spring 14 is fixedly connected between the piston plate 13 and the inner wall of the air pressure box 6, and two pairs of blocks 16 are symmetrically arranged between the two piston plates 13. The connecting spring 14 is in a compressed state. When the ball valve 20 is opened, the compressed connecting spring 14 pushes the two piston plates 13 closer to each other, thereby squeezing the nitrogen or other inert gas stored between the two piston plates 13 into the gas pipe 12, and finally into the non-rigid container 1.

[0033] Working principle: After the dangerous liquid that needs hot liquid filling is filled into the non-rigid container 1, the support plate 3 slides on the slide bar 5, and the distance between the two arc-shaped fixing plates 2 is adjusted. The two arc-shaped fixing plates 2 can be sleeved on the outer wall above the non-rigid container 1, and then the two arc-shaped fixing plates 2 are fixed by fixing bolts 10 to fix them on the non-rigid container 1, and then the position of the air pressure box 6 is adjusted by the slide bar 5, so that the connector 9 at the bottom of the air pipe 12 below it is screwed with the filling port 11. Because the dangerous liquid enters the non-rigid container by hot liquid filling, The non-rigid container 1 generates a large amount of heat when the dangerous liquid is cooled. When the inert gas filled between the arc plate 18 and the inner wall of one side of the arc cavity 17 expands after encountering the heat, the two arc plates 18 can compress the connecting spring 2 19 and move, so that the gas stored between the two arc plates 18 is squeezed into the connecting pipe 1 8, and the gas in the connecting pipe 1 8 enters the space formed between the piston plate 24 and the inner wall of the top of the storage box 21. As more and more gas enters, the piston plate 24 can move downward with the rack 1 22. The gear 23 moves, and the rack 22 meshes with the gear 23, so that the gear 23 rotates, and the closed ball valve 20 can be opened. When the ball valve 20 is opened, the compressed connecting spring 14 pushes the two piston plates 13 closer to each other, so that the nitrogen or other inert gas stored between the two piston plates 13 is squeezed into the gas pipe 12, and finally enters the non-rigid container 1. When the internal pressure of the non-rigid container 1 decreases, the inert gas is supplemented to keep the pressure inside and outside the non-rigid container 1 balanced, thereby ensuring the strength performance of the non-rigid container 1 packaging container, eliminating safety hazards, and when dangerous liquids After cooling, the air pressure inside and outside the non-rigid container 1 is in a balanced state. No heat is generated at this time, so the inert gas filled between the arc plate 18 and the inner wall of one side of the arc cavity 17 begins to shrink, and under the action of the rebound force of the connecting spring 219, the arc plate 18 is reset. At the same time, the gas above the piston plate 24 will return to the space between the two arc plates 18, and under the action of the rebound force of the connecting spring 25, the piston plate 24 is reset with the rack 1 22, so that the ball valve 20 is closed through the gear 23, and the nitrogen or inert gas in the air pressure box 6 will no longer escape.

[0034] Example 2: Reference Figure 1-Figure 7, air pressure balancing device, compared with Example 1, on the basis of Example 1, a mounting bracket 28 is fixedly connected to the outer wall of the top of the connecting head 9, and a threaded rod 29 is threadedly slidably connected to the top of the mounting bracket 28, a knob 30 is fixedly connected to the top of the threaded rod 29, and a pressing plate 27 is rotatably connected to the bottom of the threaded rod 29, the pressing plate 27 is slidably connected to the inner wall of the mounting bracket 28, and an airbag 26 is arranged between the pressing plate 27 and the top of the connecting head 9. When the connecting head 9 is screwed with the filling port 11, the threaded rod 29 is rotated by the knob 30 to move the threaded rod 29 downward, which can synchronously make the pressing plate 27 slide downward, thereby squeezing the airbag 26.

[0035] As a further solution in the present invention, an annular groove 32 is provided above the inner wall of the connecting head 9, and a sealing ring 34 is provided inside the annular groove 32, an annular airbag 31 is provided between the sealing ring 34 and the inner wall of the annular groove 32, and a connecting pipe 2 33 is connected between the air inlet end of the annular airbag 31 and the air outlet end of the airbag 26. The gas in the airbag 26 will be squeezed out and enter the annular airbag 31 through the connecting pipe 2 33. The annular airbag 31 expands after receiving the gas, which can push the sealing ring 34 to fit tightly against the outer wall of the filling port 11 to form a sealing structure, thereby avoiding leakage of the inert gas when it is input into the non-rigid container 1.

[0036] Working principle: When the connector 9 is screwed with the filling port 11, the threaded rod 29 is rotated by the knob 30 to move the threaded rod 29 downward, which can simultaneously make the pressing plate 27 slide downward, thereby squeezing the airbag 26. The gas in the airbag 26 will be squeezed out and enter the annular airbag 31 through the connecting tube 2 33. The annular airbag 31 expands after receiving the gas, and can push the sealing ring 34 to fit tightly against the outer wall of the filling port 11, forming a sealing structure to avoid leakage of the inert gas input into the non-rigid container 1.

[0037] Example 3: Reference Figure 1-Figure 8 , air pressure balancing device, compared with embodiment 2, on the basis of embodiment 2, a transparent cover 36 is provided under the gear 23, and the transparent cover 36 is fixedly connected to the top outer wall of the connecting head 9, and a pressing plate 37 is slidably connected to the inner wall of the transparent cover 36.

[0038] As a further solution of the present invention, a rack 235 is fixedly connected to the outer wall of the top of the pressing plate 27, and the rack 235 is meshed with the gear 23. A piezochromic material 38 is arranged between the pressing plate 27 and the inner cover at the bottom of the transparent cover 36. In the process of the inert gas in the air pressure box 6 balancing the air pressure of the non-rigid container, the ball valve 20 is opened under the action of the driving mechanism, and the gear 23 can make the rack 235 move upward, so that the pressing plate 27 no longer squeezes the piezochromic material 38, so that the piezochromic material 38 will not produce color. The color changes, and when the dangerous liquid in the non-rigid container is cooled, and the air pressure inside and outside the non-rigid container is balanced, the driving mechanism closes the ball valve 20 through the gear 23, so that the gear 23 can move the rack 2 35 downward. In this process, the rack 2 35 presses the pressure-changing color material 38 through the pressing plate 2 37. The color of the pressure-changing color material 38 changes after being pressed, so that the staff can clearly perceive at a glance that the air pressure in the non-rigid container 1 is balanced and the dangerous liquid has been cooled, so as to disassemble the device.

[0039] Working principle: During the process of the inert gas in the air pressure box 6 balancing the air pressure of the non-rigid container, the ball valve 20 is opened by the driving mechanism, and at the same time, the gear 23 can make the rack 2 35 move upward, so that the pressing plate 2 37 no longer squeezes the piezochromic material 38, so that the piezochromic material 38 will not change color. When the dangerous liquid in the non-rigid container is cooled and the air pressure inside and outside the non-rigid container is balanced, the driving mechanism closes the ball valve 20 through the gear 23, so that the gear 23 can move the rack 2 35 downward. In this process, the rack 2 35 presses the piezochromic material 38 through the pressing plate 2 37. The color of the pressure plate color material 38 will change after being pressed, so that the staff can perceive at a glance that the air pressure of the non-rigid container 1 is balanced and the dangerous liquid has been cooled, so that the device can be disassembled.

[0040] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A gas pressure balancing device, comprising a non-rigid container (1), wherein a filling port (11) is arranged at the top of the non-rigid container (1), characterized in that: The outer walls of both sides of the non-rigid container (1) are provided with arc-shaped fixing plates (2), and fixing bolts (10) are provided between the two arc-shaped fixing plates (2). The outer walls of the arc-shaped fixing plates (2) are fixedly connected with support plates (3), and the upper ends of the support plates (3) are slidably connected with sliding rods (5). An air pressure box (6) is fixedly connected between the outer walls on the opposite sides of the two sliding rods (5), and the other sides of the sliding rods (5) are fixedly connected with a limiting plate (4). The top outer wall of the air pressure box (6) is provided with a one-way inflation The air pressure box (6) has a gas supply pipe (12) at its bottom, the bottom of the gas supply pipe (12) is sealed and rotatably connected to a connector (9), and the connector (9) is screwed and connected to the filling port (11), an extrusion mechanism is provided inside the gas pressure box (6), and the inside of the gas pressure box (6) is filled with nitrogen or other inert gas, a ball valve (20) is provided inside the gas supply pipe (12), and a gear (23) is provided at the rotating end of the ball valve (20), and a driving mechanism is provided on one side of the gear (23).

2. The air pressure balancing device according to claim 1, characterized in that: The driving mechanism comprises an arc-shaped cavity (17), wherein the arc-shaped cavity (17) is arranged in the middle of one of the arc-shaped fixed plates (2), and the inner wall of the arc-shaped cavity (17) is sealed and slidably connected with two arc-shaped plates (18), a connecting spring (19) is fixedly connected between the two arc-shaped plates (18), and an inert gas that expands when heated is filled between each arc-shaped plate (18) and the inner wall of one side of the arc-shaped cavity (17), a connecting pipe (8) is connected to the space formed between the two arc-shaped plates (18), and a guide rod (7) is arranged above the arc-shaped cavity (17).

3. The air pressure balancing device according to claim 2, characterized in that: A storage box (21) is arranged above the gear (23), the storage box (21) is fixedly connected to the bottom outer wall of the air pressure box (6), and a rack one (22) is arranged at the bottom of the storage box (21), the inner wall of the storage box (21) is sealingly and slidably connected to a piston plate two (24), and a connecting spring three (25) is fixedly connected between the piston plate two (24) and the top inner wall of the storage box (21), the top end of the rack one (22) is fixedly connected to the bottom outer wall of the piston plate two (24), and the rack one (22) is meshed with the gear (23), and the top end of the connecting pipe one (8) passes through the guide rod (7) and is connected to the space above the piston plate two (24).

4. The air pressure balancing device according to claim 3, characterized in that: The extrusion mechanism comprises two piston plates (13), the two piston plates (13) are symmetrically sealed and slidably connected inside the air pressure box (6), and a connecting spring (14) is fixedly connected between the piston plate (13) and the inner wall of the air pressure box (6), two pairs of stoppers (16) are symmetrically arranged between the two piston plates (13), and the connecting spring (14) is in a compressed state.

5. The air pressure balancing device according to claim 1, characterized in that: The top outer wall of the connecting head (9) is fixedly connected to a mounting frame (28), and the top of the mounting frame (28) is threadedly slidably connected to a threaded rod (29), the top of the threaded rod (29) is fixedly connected to a knob (30), and the bottom of the threaded rod (29) is rotatably connected to a pressing plate (27), the pressing plate (27) is slidably connected to the inner wall of the mounting frame (28), and an air bag (26) is provided between the pressing plate (27) and the top of the connecting head (9).

6. The air pressure balancing device according to claim 5, characterized in that: An annular groove (32) is provided above the inner wall of the connector (9), and a sealing ring (34) is provided inside the annular groove (32). An annular airbag (31) is provided between the sealing ring (34) and the inner wall of the annular groove (32), and a second connecting pipe (33) is connected between the air inlet end of the annular airbag (31) and the air outlet end of the airbag (26).

7. The air pressure balancing device according to claim 1, characterized in that: A transparent cover (36) is provided below the gear (23), and the transparent cover (36) is fixedly connected to the outer wall at the top of the connector (9), and a second pressing plate (37) is slidably connected to the inner wall of the transparent cover (36).

8. The air pressure balancing device according to claim 7, characterized in that: The top outer wall of the second pressing plate (37) is fixedly connected with a second rack (35), and the second rack (35) is meshed with the gear (23). A piezochromic material (38) is arranged between the second pressing plate (37) and the bottom inner cover of the transparent cover (36).

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