Foundation pit air film control device

Abstract

The invention provides a foundation pit air film control device, and relates to the field of foundation pit construction, the foundation pit air film control device comprises symmetrically arranged bases, the tops of the bases are sequentially spliced with bottom pipes, splicing pipes and top pipes, and a self-adaptive adjusting assembly is arranged between the two top pipes; the adjusting assembly comprises a center pipe arranged between the two sets of top pipes, the outer side of the center pipe is symmetrically sleeved with connecting blocks, and bent pipes are symmetrically arranged on the left side and the right side of the center pipe. The bimetallic strip is matched with the bent pipe, the temperature in the gas film is sensed through the bimetallic strip, upward bending of different degrees is achieved, and then opening and closing of the ventilation opening are achieved; and meanwhile, certain high-pressure gas is stored through the bottom pipe, the splicing pipe and the top pipe which are arranged, and the gas outlet valve is matched, so that emergency supplementation is achieved through the temporarily stored high-pressure gas when the gas film is locally broken, and workers are warned through transportation of the high-pressure gas and sound generated by the broken gas film.

Description

Technical Field

[0001] The invention relates to the field of foundation pit construction, and in particular to a foundation pit air film control device. Background Art

[0002] The foundation pit air film, also known as the foundation pit protective film, is a temporary protective facility made of high-strength, waterproof and anti-corrosion materials. It forms a closed space by inflation, effectively isolates the external environment, prevents groundwater, soil and other impurities from entering the construction area, and reduces dust and noise pollution during construction. The existing foundation pit air film control device usually needs to manually or automatically control the opening and closing of the top vents and the opening and closing angles according to the internal temperature sensor. This method has a slow response and is too dependent on the detection of the temperature sensor. At the same time, the existing foundation pit air film control device cannot make emergency treatment when the air film is partially ruptured, and cannot mark the rupture location in time, resulting in untimely remediation of the air film, and there are certain disadvantages when it is used.

[0003] Therefore, we made improvements on this and proposed a foundation pit air film control device. Summary of the invention

[0004] The purpose of the present invention is to: with respect to the existing control devices for foundation pit air membranes, it is usually necessary to manually or automatically control the opening and closing of the top vents, as well as the opening and closing angles, based on the temperature sensors inside them. This method has a slow response and is overly dependent on the detection of the temperature sensors. At the same time, the existing control devices for foundation pit air membranes are unable to make emergency treatments when the air membrane is partially ruptured, and cannot promptly mark the rupture location, resulting in untimely remediation of the air membrane, which results in certain drawbacks during use.

[0005] In order to achieve the above-mentioned purpose of the invention, the present invention provides a foundation pit air film control device to improve the above-mentioned problem.

[0006] The specific application is as follows:

[0007] It comprises a symmetrically arranged base, the top of which is sequentially spliced ​​with a bottom tube, a spliced ​​tube and a top tube, and an adjustment component for adaptive adjustment is arranged between two groups of top tubes;

[0008] The adjustment component includes a central tube arranged between the two groups of top tubes, a connecting block is symmetrically sleeved on the outer side of the central tube, curved tubes are symmetrically arranged on the left and right sides of the central tube, and a bimetallic strip is symmetrically arranged on the bottom of the curved tube.

[0009] As a preferred technical solution of the present application, side grooves are symmetrically opened on the left and right sides of the central tube, and the central tube is sleeved with a rotating plate through the side grooves.

[0010] As a preferred technical solution of the present application, a connecting groove is provided on the inner side of the curved pipe, and the connecting groove matches the rotating plate, and a clamping groove is provided on the bottom of the curved pipe.

[0011] As a preferred technical solution of the present application, a spring sheet is arranged in the middle of the two groups of bimetal sheets, and a U-shaped tube is installed at one end of the bimetal sheet and the spring sheet away from the bent pipe, and the two ends of the U-shaped tube respectively penetrate the side wall of the top pipe and extend into the interior thereof.

[0012] As a preferred technical solution of the present application, a steering block is fixedly installed in the middle part of the inner cavity of the U-shaped tube, sliders are symmetrically arranged in the inner cavity of the U-shaped tube about the steering block, and pull ropes are symmetrically arranged at the upper and lower ends of the spring sheet, and the other ends of the two groups of pull ropes respectively pass through the interior of the U-shaped tube and the upper and lower parts of the steering block, and extend to the inner sides of the two groups of sliders.

[0013] As a preferred technical solution of the present application, the inner cavity of the base has connecting cloth wound symmetrically on the left and right, and the ends of the two groups of connecting cloth are respectively installed with a clamping block and a buckle.

[0014] As a preferred technical solution of the present application, reinforcing columns are symmetrically arranged between the two groups of connecting cloths, and compression springs are arranged on the outside of the reinforcing columns. The top of the compression spring is connected to the outside of the reinforcing column, and the bottom of the compression spring is connected to the inner cavity of the base. The middle and lower parts of the reinforcing column pass through the bottom of the base and extend to its outside.

[0015] As a preferred technical solution of the present application, an air outlet groove is opened through the middle part of the spliced ​​tube, an air inlet groove is symmetrically arranged inside the spliced ​​tube about the air outlet groove, an air outlet groove is opened in the middle and lower part of the top pipe, and air inlet grooves are symmetrically opened on both sides of the air outlet groove, the tops of the two groups of air inlet grooves are respectively connected with the two groups of U-shaped tubes, a bursting piece is arranged on the outside of the spliced ​​tube, and the inner side of the bursting piece is connected with the air outlet groove.

[0016] As a preferred technical solution of the present application, an air outlet groove is opened through the middle and upper part of the bottom tube, and air inlet grooves are symmetrically opened on both sides of the air outlet groove. The bottoms of the air outlet groove and the air inlet groove are both arc-shaped and extend to the outside of the bottom tube.

[0017] As a preferred technical solution of the present application, the middle pipe of the air inlet groove is connected to an air inlet valve, and the middle pipe of the air outlet groove is connected to an air outlet valve.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] In the scheme of this application:

[0020] 1. In order to solve the problem that the air film control device for foundation pit in the prior art cannot quickly respond to the opening and closing of the vent according to the internal temperature, the present application realizes the sensing of the temperature inside the air film through the bimetallic strip and realizes the upward bending to different degrees, thereby realizing the opening and closing of the vent;

[0021] 2. In order to solve the problem that emergency remedies and warnings cannot be carried out in the prior art, the present application stores a certain amount of high-pressure gas by setting up a bottom pipe, a spliced ​​pipe and a top pipe, and cooperates with an outlet valve to achieve emergency replenishment through the temporarily stored high-pressure gas when the air film is partially ruptured, and warns the staff through the transportation of high-pressure gas and the sound generated by the ruptured air film;

[0022] 3. By setting up the base and the connecting cloth, card blocks and buckles inside it, the components of the device can be bundled through the card blocks and buckles that match each other, solving the problem of messy components and difficulty in fixing components during transportation in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the structure of the foundation pit air film control device provided in this application;

[0024] Figure 2 A schematic diagram of the connection structure of the spliced ​​pipe of the foundation pit air film control device provided in this application;

[0025] Figure 3 A cross-sectional view of the internal structure of the top pipe of the foundation pit air film control device provided in this application;

[0026] Figure 4 A schematic diagram of the structure of the splicing pipe of the foundation pit air film control device provided in this application;

[0027] Figure 5 A schematic diagram of the connection structure of the bottom pipe of the foundation pit air film control device provided in this application;

[0028] Figure 6 A cross-sectional view of the internal structure of the base of the foundation pit air film control device provided in this application;

[0029] Figure 7 A schematic diagram of the structure of the adjustment assembly of the foundation pit air film control device provided in this application;

[0030] Figure 8 A schematic diagram of the connection structure of the central tube of the foundation pit air film control device provided in this application;

[0031] Fig. 9 This is an exploded view of the local structure inside the U-shaped tube of the foundation pit air film control device provided in this application.

[0032] Indicated in the figure:

[0033] 1. Base; 2. Bottom pipe; 3. Splicing pipe; 4. Top pipe; 5. Inlet valve; 6. Outlet valve; 7. Bursting disc;

[0034] 8. Adjustment assembly; 801. U-shaped tube; 802. Steering block; 803. Sliding block; 804. Pull rope; 805. Shrapnel; 806. Bimetallic sheet; 807. Center tube; 808. Connecting block; 809. Bend tube; 810. Connecting groove; 811. Clamping groove; 812. Side groove; 813. Rotating plate;

[0035] 9. Connecting cloth; 10. Block; 11. Buckle; 12. Reinforcement column; 13. Compression spring; 14. Air inlet groove; 15. Air outlet groove. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme 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 only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0037] As described in the background technology, the existing control device for the foundation pit air film usually needs to manually or automatically control the opening and closing of the top vents, as well as the opening and closing angles, based on the temperature sensor inside. This method has a slow response and is too dependent on the detection of the temperature sensor. At the same time, the existing control device for the foundation pit air film cannot make emergency treatment when the air film is partially ruptured, and cannot mark the rupture location in time, resulting in untimely remediation of the air film, which has certain disadvantages when used.

[0038] In order to solve this technical problem, the present invention provides a foundation pit air film control device, which is applied to an adaptive foundation pit air film control device.

[0039] Specifically, please refer to Figure 1-Figure 9 The foundation pit air film control device specifically includes a symmetrically arranged base 1, a bottom pipe 2, a spliced ​​pipe 3 and a top pipe 4 are sequentially spliced ​​on the top of the base 1, and an adaptively adjustable adjustment component 8 is arranged between the two groups of top pipes 4;

[0040] The adjustment assembly 8 includes a central tube 807 disposed between the two groups of top tubes 4, the two ends of the central tube 807 are respectively connected with the two groups of top tubes 4 by bolts, the outer side of the central tube 807 is symmetrically sleeved with a connecting block 808, and the left and right sides of the central tube 807 are symmetrically provided with a bent tube 809, the bent tube 809 is an elastic tube, and the two ends of the bent tube 809 are spherical, the two ends of the bent tube 809 are respectively spherically sleeved with the two groups of connecting blocks 808, and the bottom of the bent tube 809 is symmetrically provided with a bimetallic strip 806, and the bending direction of the bimetallic strip 806 is upward;

[0041] The bimetallic strip 806 is provided to realize corresponding bending according to the temperature inside the air film in real time, thereby driving the bending pipe 809 to bend and deform, thereby realizing adaptive opening of the ventilation pipe.

[0042] The foundation pit air film control device provided by the present invention has a bimetallic strip cooperated with a bent pipe, so that the temperature inside the air film can be sensed by the bimetallic strip, and different degrees of upward bending can be achieved, thereby realizing the opening and closing of the vents; at the same time, a certain amount of high-pressure gas is stored by the arranged bottom pipe, spliced ​​pipe and top pipe, and in cooperation with the air outlet valve, when the air film is partially ruptured, emergency replenishment can be achieved through the temporarily stored high-pressure gas, and the transportation of the high-pressure gas and the sound generated by the ruptured air film can be used to alert the staff.

[0043] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings.

[0044] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0045] 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.

[0046] Example 1, please refer to Figure 7 , Figure 8 and Fig. 9 , a foundation pit air film control device, wherein side grooves 812 are symmetrically opened on the left and right sides of the center tube 807, the middle of the side grooves 812 is connected with the inner cavity of the center tube 807, the center tube 807 is sleeved with a rotating plate 813 through the side grooves 812, the rotating plate 813 is connected to the center tube 807 through a torsion spring, and the inner cavity of the center tube 807 is connected with the top tube 4, and the outer side of the rotating plate 813 is connected to the inside of the side grooves 812 through a transparent film;

[0047] By continuously delivering gas to the inner cavity of the central tube 807, the rotating plate 813 is driven to rotate under the action of gas pressure, and the rotating rotating plate 813 can push the curved tube 809 to deform, thereby opening the ventilation tube. At this time, the central tube 807 can be sealed by the transparent film.

[0048] Please refer to Figure 7 , Figure 8 and Fig. 9 A foundation pit air film control device, wherein a connecting groove 810 is provided on the inner side of a curved pipe 809, and the connecting groove 810 matches a rotating plate 813, and a clamping groove 811 is provided on the bottom of the curved pipe 809;

[0049] The bent pipe 809 is connected to the rotating plate 813 through the connecting groove 810, so that it can be reinforced in harsh environments to prevent the bent pipe 809 and the central pipe 807 from shaking.

[0050] Further, such as Figure 7 , Figure 8 and Fig. 9 As shown, a spring sheet 805 is provided in the middle of the two groups of bimetallic sheets 806, a protrusion is provided at one end of the upper surface of the spring sheet 805, and the protrusion matches the slot 811, and a U-shaped tube 801 is installed at one end of the bimetallic sheet 806 and the spring sheet 805 away from the bent tube 809, and the two ends of the U-shaped tube 801 respectively penetrate the side walls of the top tube 4 and extend into the interior thereof.

[0051] Further, such as Figure 7 , Figure 8 and Fig. 9 As shown, a steering block 802 is fixedly installed in the middle of the inner cavity of the U-shaped tube 801, a slider 803 is symmetrically arranged in the inner cavity of the U-shaped tube 801 about the steering block 802, and a pull rope 804 is symmetrically arranged at the upper and lower ends of the spring piece 805, and the other ends of the two groups of pull ropes 804 respectively penetrate the interior of the U-shaped tube 801 and the upper and lower parts of the steering block 802, and extend to the inner sides of the two groups of sliders 803;

[0052] By changing the air pressure difference on the outside of the two groups of sliders 803 in the inner cavity of the U-shaped tube 801, the two groups of sliders 803 can be pushed to slide synchronously, and then the spring piece 805 can be bent upward or downward by the corresponding stretching. Bending upward will cause the curved tube 809 to deform, thereby opening the ventilation tube, and bending downward will separate the spring piece 805 from the curved tube 809. At this time, the curved tube 809 rebounds toward the central tube 807 under its own action, thereby fully sealing the top of the air film, making it convenient to deal with severe weather.

[0053] Example 2 further optimizes the foundation pit air film control device provided in Example 1. Specifically, Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the inner cavity of the base 1 is symmetrically wound with connecting cloth 9, a rotating rod is provided in the middle of the connecting cloth 9, and the rotating rod is sleeved with the base 1 through a torsion spring, and a clamping block 10 and a buckle 11 are respectively installed at the ends of the two groups of connecting cloth 9, and the base 1 is sleeved with the clamping block 10 and the buckle 11;

[0054] The connecting cloth 9 is used to bundle the components when transporting the device to facilitate transportation, and can also increase the overall connectivity when the air film is spliced.

[0055] Further, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, reinforcing columns 12 are symmetrically arranged between the two groups of connecting cloths 9, the top of the reinforcing column 12 is connected to the outer side of the connecting cloth 9, and a compression spring 13 is arranged on the outer side of the reinforcing column 12, the top of the compression spring 13 is connected to the outer side of the reinforcing column 12, and the bottom of the compression spring 13 is connected to the inner cavity of the base 1, and the middle and lower parts of the reinforcing column 12 pass through the bottom of the base 1 and extend to the outer side thereof;

[0056] When the connecting cloth 9 contracts, it squeezes the reinforcing column 12 so that the reinforcing column 12 passes through the base 1, thereby facilitating reinforcement when the base 1 is installed.

[0057] Further, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, an air outlet groove 15 is opened through the middle of the spliced ​​tube 3, and an air inlet groove 14 is symmetrically arranged inside the spliced ​​tube 3 about the air outlet groove 15. An air outlet groove 15 is opened in the middle and lower part of the top pipe 4, and air inlet grooves 14 are symmetrically opened on both sides of the air outlet groove 15. The tops of the two groups of air inlet grooves 14 are respectively connected with the two groups of U-shaped tubes 801. A bursting piece 7 is arranged on the outside of the spliced ​​tube 3, and the inner side of the bursting piece 7 is connected with the air outlet groove 15.

[0058] Further, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, an air outlet groove 15 is formed through the middle and upper part of the bottom tube 2 , and air inlet grooves 14 are formed symmetrically on both sides of the air outlet groove 15 . The bottoms of the air outlet groove 15 and the air inlet groove 14 are both arc-shaped and extend to the outside of the bottom tube 2 .

[0059] Further, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the middle part of the air inlet groove 14 is connected to the air inlet valve 5, and the middle part of the air outlet groove 15 is connected to the air outlet valve 6.

[0060] The use process of the foundation pit air film control device provided by the present invention is as follows:

[0061] Transportation: The device is initially transported, and is wrapped by two sets of U-shaped tubes 801, and is combined with two sets of bases 1 and the connecting cloths 9, the clamping blocks 10 and the buckles 11 symmetrically arranged inside the bases 1 in sequence, and other components are bundled for easy transportation;

[0062] Splicing: When in use, the base 1, the bottom tube 2, one or more groups of splicing tubes 4 and the top tube 4 are spliced ​​together in sequence, then the adjusting component 8 is taken out, and the two ends of the central tube 807 set in the middle are spliced ​​with the two groups of top tubes 4 bolts, and then the central tube 807 is connected with the air inlet groove 14 through a hose. At this time, the air film is wrapped around the outside of the base 1, the bottom tube 2, one or more groups of splicing tubes 4 and the adjusting component 8 in sequence. At this time, ensure that the central tube 807 is located on the outside of the air film, and finally the air film is inflated through the two groups of air inlets symmetrically set on the outside of the bottom tube 2 in conjunction with an external air pump;

[0063] Adjustment: When the temperature inside the air film is too high, the bimetallic strip 806 is continuously heated up and bends upward, and then the bent bimetallic strip 806 pushes the curved tube 809 on the top to deform, and pulls the connecting block 808 to slide along the central tube 807, so that the air film wrapped on the outside of the two sets of curved tubes 809 is separated, thereby forming a ventilation hole to achieve ventilation;

[0064] Detection and pressure relief: When the local air film is ruptured, the air pressure inside and outside the air intake valve 5 at the ruptured part is unbalanced. At this time, the air intake valve 5 opens, and the gas temporarily stored in the air intake valve 5 is transported to the ruptured air film, so as to achieve emergency rescue. At the same time, the pressure sensor on the outer surface of the air intake valve 5 alarms, and the gas transported to the ruptured air film can also blow it, making it make a sound, thereby alerting the staff;

[0065] Emergency pressure relief: when the air pressure inside the air film is suddenly too high and the air outlet valve 6 cannot provide emergency pressure relief, and the pressure reaches a critical value, the air pressure will break the bursting disc and release pressure through the air outlet groove 15, thereby preserving the air film.

[0066] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0067] Obviously, the embodiments described above are only some embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are given in the accompanying drawings, but they do not limit the patent scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific embodiments, or to perform equivalent replacements for some of the technical features therein. Any equivalent structure made using the contents of the specification and drawings of the present invention, directly or indirectly used in other related technical fields, is also within the scope of patent protection of the present invention.

Claims

1. A foundation pit air film control device, characterized in that: It comprises a symmetrically arranged base (1), the top of which is sequentially spliced ​​with a bottom tube (2), a spliced ​​tube (3) and a top tube (4), and an adaptively adjustable adjustment component (8) is arranged between two groups of the top tubes (4); The adjustment assembly (8) comprises a central tube (807) arranged between the two groups of top tubes (4), a connecting block (808) is symmetrically sleeved on the outer side of the central tube (807), curved tubes (809) are symmetrically arranged on the left and right sides of the central tube (807), and a bimetallic strip (806) is symmetrically arranged at the bottom of the curved tube (809).

2. A foundation pit air film control device according to claim 1, characterized in that: Side grooves (812) are symmetrically provided on the left and right sides of the central tube (807), and a rotating plate (813) is sleeved on the central tube (807) through the side grooves (812).

3. A foundation pit air film control device according to claim 2, characterized in that: A connecting groove (810) is provided on the inner side of the curved tube (809), and the connecting groove (810) matches the rotating plate (813), and a clamping groove (811) is provided on the bottom of the curved tube (809).

4. A foundation pit air film control device according to claim 3, characterized in that: A spring sheet (805) is arranged in the middle of the two groups of bimetal sheets (806), and a U-shaped tube (801) is installed at one end of the bimetal sheets (806) and the spring sheet (805) away from the bent tube (809), and the two ends of the U-shaped tube (801) respectively penetrate the side wall of the top tube (4) and extend into the inside thereof.

5. A foundation pit air film control device according to claim 4, characterized in that: A steering block (802) is fixedly installed in the middle of the inner cavity of the U-shaped tube (801), and sliders (803) are symmetrically arranged in the inner cavity of the U-shaped tube (801) with respect to the steering block (802). Pull ropes (804) are symmetrically arranged at the upper and lower ends of the spring sheet (805), and the other ends of the two groups of pull ropes (804) respectively penetrate the interior of the U-shaped tube (801) and the upper and lower parts of the steering block (802), and extend to the inner sides of the two groups of sliders (803).

6. A foundation pit air film control device according to claim 5, characterized in that: The inner cavity of the base (1) has connecting cloths (9) wound symmetrically on both sides, and the ends of the two groups of connecting cloths (9) are respectively installed with a clamping block (10) and a buckle (11).

7. A foundation pit air film control device according to claim 6, characterized in that: A reinforcing column (12) is symmetrically arranged between the two groups of connecting cloths (9), and a compression spring (13) is arranged on the outer side of the reinforcing column (12). The top of the compression spring (13) is connected to the outer side of the reinforcing column (12), and the bottom of the compression spring (13) is connected to the inner cavity of the base (1). The middle and lower parts of the reinforcing column (12) pass through the bottom of the base (1) and extend to the outer side thereof.

8. The foundation pit air film control device according to claim 7, characterized in that: The middle of the spliced ​​tube (3) is provided with an air outlet groove (15), the inside of the spliced ​​tube (3) is symmetrically provided with an air inlet groove (14) about the air outlet groove (15), the middle and lower part of the top tube (4) is provided with an air outlet groove (15), and the two sides of the air outlet groove (15) are symmetrically provided with air inlet grooves (14), the tops of the two groups of the air inlet grooves (14) are respectively connected with the two groups of the U-shaped tubes (801), and the outer side of the spliced ​​tube (3) is provided with a bursting piece (7), and the inner side of the bursting piece (7) is connected with the air outlet groove (15).

9. The foundation pit air film control device according to claim 8, characterized in that: An air outlet groove (15) is provided through the middle and upper part of the bottom tube (2), and air inlet grooves (14) are symmetrically provided on both sides of the air outlet groove (15). The bottoms of the air outlet groove (15) and the air inlet groove (14) are both arc-shaped and extend to the outside of the bottom tube (2).

10. A foundation pit air film control device according to claim 9, characterized in that: The middle pipe of the air inlet groove (14) is connected to an air inlet valve (5), and the middle pipe of the air outlet groove (15) is connected to an air outlet valve (6).

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