Stress monitoring device for large-aperture steel corrugated pipe

Abstract

The invention discloses a stress monitoring device for a large-aperture steel corrugated pipe, and belongs to the field of detection device.The stress monitoring device comprises a mounting box, the mounting box is connected to the top wall of the middle of a corrugated pipe body, an arc-shaped plate attached to the inner wall of the corrugated pipe body is arranged on the contact face of the mounting box and the corrugated pipe body, and a supporting plate is connected into the mounting box; a sliding rod is vertically connected to the middle of the supporting plate in a penetrating and sliding mode, a U-shaped frame is connected to the top of the sliding rod, a limiting plate is connected to the bottom of the sliding rod, a first spring is connected between the limiting plate and the supporting plate, and a first stress sensor and a second stress sensor are symmetrically connected into the mounting box; a first pressure-sensitive switch for controlling the first stress sensor and a second pressure-sensitive switch for controlling the second stress sensor are respectively arranged at the upper part and the lower part of the limiting plate; according to the device, a sensor array does not need to be arranged in the corrugated pipe body, cost is saved, and meanwhile subsequent data processing steps are omitted.

Description

Technical Field

[0001] The invention relates to the technical field of detection devices, in particular to a force monitoring device for a large-aperture steel bellows. Background Art

[0002] In the fields of civil engineering, bridge construction, tunnel engineering and pipeline laying, large-diameter steel corrugated pipes are widely used as an important structural material due to their good flexibility, corrosion resistance and strong load-bearing capacity. However, in actual use, corrugated pipes are often subjected to complex stresses from different directions, such as lateral extrusion, top or bottom pressure, etc. These stresses may cause the corrugated pipes to deform or even be damaged, thus affecting the safety and stability of the entire engineering structure.

[0003] The traditional bellows stress monitoring method mainly relies on arranging multiple sensor arrays inside or outside the bellows to evaluate the overall stress state of the bellows by measuring the stress changes at different positions. However, this method has many shortcomings: first, the installation and maintenance costs of the sensor array are high, which increases the overall investment in engineering construction; second, due to the large number of sensors and the huge amount of data collected, the subsequent data processing and analysis are complex and time-consuming. Summary of the invention

[0004] The purpose of the present invention is to provide a force monitoring device for a large-aperture steel bellows, which solves the problem of high cost and large amount of subsequent data processing when arranging multiple sensor arrays inside or outside the bellows.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a force monitoring device for a large-aperture steel corrugated pipe, comprising an installation box, the installation box is connected to the top wall of the middle part of the corrugated pipe body, an arc-shaped plate that fits the inner wall of the corrugated pipe body is arranged on the contact surface between the installation box and the corrugated pipe body, a support plate is connected inside the installation box, a slide rod is vertically penetrated and slidably connected to the middle part of the support plate, a U-shaped frame is connected to the top of the slide rod, a limit plate is connected to the bottom of the slide rod, a first spring is connected between the limit plate and the support plate, a first stress sensor and a second stress sensor are symmetrically connected inside the installation box, and a first pressure-sensitive switch for controlling the first stress sensor and a second pressure-sensitive switch for controlling the second stress sensor are respectively arranged at the upper and lower parts of the limit plate;

[0006] When the installation box is installed on the bellows body, the inner wall of the bellows body is in contact with the two fulcrums at the top of the U-shaped frame and the upper surface of the arc plate, and the first spring is in an incompletely stretched state. When the bellows body is subjected to extrusion pressure from both sides, the inner walls of the bellows body on both sides of the installation box approach each other, so that the U-shaped frame is pushed downward relative to the installation box, the first spring is further stretched, and the limit plate squeezes the second pressure-sensitive switch. Moreover, when the bellows body is subjected to extrusion pressure from the upper part, the top of the bellows body collapses, so that the inner walls of the bellows body on both sides of the installation box move away from each other, so that the first spring elastically releases and contracts, so that the U-shaped frame moves upward, and the limit plate squeezes the first pressure-sensitive switch.

[0007] Preferably, a threaded rod is connected to the upper surface of the arc-shaped plate, the threaded rod passes through the top wall of the bellows body, and two nuts are threadedly connected to the threaded rod, and the two nuts are respectively in contact with the inner wall and the outer wall of the bellows body.

[0008] Preferably, two sliding seats are symmetrically connected in the installation box, and two sliders are symmetrically connected to the upper surface of the support plate. A cavity is opened in the two sliding seats, and the side walls of the two sliders are respectively fitted with the inner walls of the two cavities. After the sliding rod moves up or down, the slider moves up or down relative to the sliding seat so that the first spring recovers to a length close to the initial length in the unstretched state.

[0009] Preferably, the support plate is connected to a micro air pump, the micro air pump is connected to an air injection pipe, the air injection pipe is connected to the cavity, the air injection pipe is connected to an exhaust pipe, an electromagnetic valve is provided on the air injection pipe between the cavity and the exhaust pipe, and a pressure valve is provided on the exhaust pipe;

[0010] After the limit plate moves downward to squeeze the second pressure-sensitive switch, the solenoid valve opens and the micro air pump starts, so that air is filled in the cavity and the slider drives the support plate to move downward. When the support plate moves downward to the length at which the first spring recovers to a length close to the initial length in an incompletely stretched state, the pressure in the cavity increases to the discharge value of the pressure valve, and, after the limit plate moves upward to squeeze the first pressure-sensitive switch, the solenoid valve opens and the micro air pump starts, so that the micro air pump extracts air from the cavity until negative pressure is generated in the cavity so that the pressure difference exceeds the pressure value of the pressure valve and external air enters the exhaust pipe, so that the slider drives the support plate to move upward to the length at which the first spring recovers to a length close to the initial length in an incompletely stretched state, the micro air pump stops running, and the solenoid valve closes after the pressure valve is closed.

[0011] Preferably, the gas injection pipe is connected to the two cavities, and a first diverter valve is provided at the connection between the gas injection pipe and the micro air pump.

[0012] Preferably, the two sliding seats are connected to a connecting seat that can be vertically slidably arranged, the connecting seat is vertically slidably connected to a vertical rod, the bottom of the vertical rod is connected to a mounting frame, a second spring is connected between the mounting frame and the connecting seat, and the first pressure-sensitive switch and the second pressure-sensitive switch are respectively connected to the two connecting seats.

[0013] Preferably, grooves are provided on the two connecting seats, two sides of the limit plate are respectively snapped into the two grooves, and the first pressure-sensitive switch and the second pressure-sensitive switch are respectively connected to the top wall and the bottom wall of the two grooves.

[0014] Preferably, a sliding groove cooperating with the connecting seat is provided on the side of the sliding seat, a rectangular frame is slidably connected in the sliding groove, the rectangular frame is perpendicular to the sliding direction of the connecting seat, and anti-slip grooves are provided on the contact surfaces of the rectangular frame and the connecting seat, and the connecting seat can be locked or unlocked on the sliding seat when the rectangular frame approaches or moves away from the connecting seat;

[0015] When the exhaust pipe discharges air, the rectangular frame slides in a direction away from the connection seat, and when the exhaust pipe stops discharging air, the rectangular frame slides in a direction close to the connection seat;

[0016] When the connecting seat is locked to the sliding seat, the limiting plate can drive the mounting frame to slide relatively to the connecting seat, and when the connecting seat is unlocked from the sliding seat, the limiting plate can drive the connecting seat to slide relatively to the sliding seat.

[0017] Preferably, a rectangular plate is connected to the sliding seat, the rectangular plate is located in the middle of the rectangular frame, two sides of the rectangular plate are respectively connected to a wedge block and a third spring, a piston cylinder is connected to the sliding seat, the piston cylinder is connected to the air guide pipe, a piston rod is slidably connected to the piston cylinder through a fourth spring, the wedge block is connected to the end of the piston rod, the wedge block and the piston rod are jointly provided with an air hole connecting the piston cylinder and the external space, the wedge block is symmetrically provided with two inclined surfaces, and when the wedge block slides, the rectangular frame can be pushed away from the connecting seat through the inclined surfaces in the opposite direction of the sliding;

[0018] When the air guide pipe injects or exhausts air into the piston cylinder, the piston rod drives the wedge block to slide.

[0019] Preferably, the number of the piston cylinders is four, and every two of the four piston cylinders are symmetrically connected to the two sides of the sliding seat, the air duct is connected to the two piston cylinders on the same side, and a second diverter valve is provided at the connection between the exhaust pipe and the air duct.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention installs the installation box at the top position in the middle of the bellows body so that the arc plate fits the inner wall of the bellows body. At this time, the U-shaped frame is squeezed by the inner wall of the bellows body and moves downward relative to the support plate in the installation box, so that the first spring is in a pre-stretched state but not fully stretched. When the bellows body is squeezed by the extrusion force on both sides, the cross-section of the bellows body presents a vertical elliptical shape. At this time, the inner walls of the bellows body on both sides of the U-shaped frame squeeze the U-shaped frame, so that the U-shaped frame is further pushed and continues to move downward relative to the support plate. At this time, the limit plate moves downward synchronously, so that the limit plate squeezes the second pressure-sensitive switch. At this time, the second stress sensor collects the pressure of the bellows body. The stress data is sent, that is, when the second stress sensor sends the stress data, the bellows body is in a state of being compressed on both sides, so that not only the required stress data can be obtained, but also the deformation trend of the bellows body can be directly known. In addition, when the bellows body is squeezed from the top, the cross-section of the bellows body is in a horizontal elliptical state. At this time, the elastic contraction of the stretched first spring causes the U-shaped frame to drive the limit plate to move up and squeeze the first pressure-sensitive switch to start the first stress sensor, thereby obtaining the deformation trend of the bellows body and the required stress data. There is no need to set a sensor array in the bellows body, which saves costs and saves subsequent data processing steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of the installation box of the present invention being installed on the corrugated pipe body;

[0023] Figure 2 It is a schematic diagram of the overall structure of the installation box of the present invention;

[0024] Figure 3 is a cross-sectional view of the installation box of the present invention;

[0025] Figure 4 It is a structural schematic diagram of the limiting plate of the present invention;

[0026] Figure 5 It is a structural schematic diagram of the mounting frame of the present invention;

[0027] Figure 6 It is a structural schematic diagram of the slider of the present invention;

[0028] Figure 7 It is a structural schematic diagram of the connection seat of the present invention;

[0029] Figure 8 For the present invention Figure 7 The structural diagram of part A in the figure;

[0030] Fig. 9 It is a structural schematic diagram of the wedge block of the present invention.

[0031] In the figure: 1. bellows body; 2. mounting box; 21. threaded rod; 22. nut; 23. arc plate; 3. sliding rod; 31. U-shaped frame; 32. limit plate; 33. first spring; 4. support plate; 41. sliding seat; 42. mounting frame; 421. vertical rod; 422. second spring; 43. first pressure-sensitive switch; 431. first stress sensor; 44. second pressure-sensitive switch; 441. second stress sensor; 45. connecting seat; 46. slider; 5. micro air pump; 51. air injection pipe; 52. first diverter valve; 53. solenoid valve; 54. exhaust pipe; 55. pressure valve; 6. rectangular frame; 61. rectangular plate; 62. wedge block; 63. third spring; 64. air hole; 65. air guide pipe; 66. second diverter valve; 67. piston cylinder; 68. piston rod; 69. fourth spring. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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 are within the scope of protection of the present invention.

[0033] Reference Figure 1 , Figure 2 , Figure 3 and Figure 5The present embodiment provides a technical solution: a force monitoring device for a large-aperture steel corrugated pipe, comprising an installation box 2, the installation box 2 being connected to the top wall in the middle of the corrugated pipe body 1, an arc-shaped plate 23 that fits the inner wall of the corrugated pipe body 1 being arranged on the contact surface between the installation box 2 and the corrugated pipe body 1, a support plate 4 being connected inside the installation box 2, a slide bar 3 being vertically penetrated and slidably connected through the middle of the support plate 4, a U-shaped frame 31 being connected to the top of the slide bar 3, a limit plate 32 being connected to the bottom of the slide bar 3, a first spring 33 being connected between the limit plate 32 and the support plate 4, a first stress sensor 431 and a second stress sensor 441 being symmetrically connected inside the installation box 2, a first pressure-sensitive switch 43 for controlling the first stress sensor 431 and a pressure-sensitive switch 43 for controlling the second stress sensor 441 being arranged at the upper and lower parts of the limit plate 32, respectively. 441 is a second pressure-sensitive switch 44; when the mounting box 2 is installed on the bellows body 1, the inner wall of the bellows body 1 fits against the two fulcrums at the top of the U-shaped frame 31 and the upper surface of the arc plate 23, and the first spring 33 is in an incompletely stretched state. When the bellows body 1 is subjected to squeezing force from both sides, the inner walls of the bellows body 1 on both sides of the mounting box 2 approach each other, so that the U-shaped frame 31 is pushed downward relative to the mounting box 2, the first spring 33 is further stretched, and the limit plate 32 squeezes the second pressure-sensitive switch 44. Moreover, when the bellows body 1 is subjected to upper squeezing force, the top of the bellows body 1 collapses, so that the inner walls of the bellows body 1 on both sides of the mounting box 2 move away from each other, so that the first spring 33 is elastically released and contracts, so that the U-shaped frame 31 moves upward, so that the limit plate 32 squeezes the first pressure-sensitive switch 43.

[0034] The working principle of the force monitoring device for large-diameter steel bellows provided in this embodiment is as follows:

[0035] When in use, the installation box 2 is installed at the top position in the middle of the bellows body 1, so that the arc plate 23 fits the inner wall of the bellows body 1, and the U-shaped frame 31 is squeezed by the inner wall of the bellows body 1 and moves downward relative to the support plate 4 in the installation box 2, so that the first spring 33 is in a pre-stretched state but not fully stretched. When the bellows body 1 is squeezed on both sides, the cross-section of the bellows body 1 presents a vertical elliptical shape. At this time, the inner walls of the bellows body 1 on both sides of the U-shaped frame 31 squeeze the U-shaped frame 31, so that the U-shaped frame 31 is further pushed and continues to move downward relative to the support plate 4. At this time, the limit plate 32 moves downward synchronously, so that the limit plate 32 squeezes the second pressure-sensitive switch 44. At this time, the second stress sensor 441 collects the pressure of the bellows. The stress data of the main body 1 is sent, that is, when the second stress sensor 441 sends the stress data, the bellows main body 1 is in a state of being compressed on both sides, so that not only the required collected stress data can be obtained, but also the deformation trend of the bellows main body 1 can be directly known. In addition, when the bellows main body 1 is squeezed from the upper part, the cross section of the bellows main body 1 is in a horizontal elliptical state. At this time, the stretched first spring 33 elastically contracts so that the U-shaped frame 31 drives the limit plate 32 to move upward and squeeze the first pressure-sensitive switch 43 so that the first stress sensor 431 is started, thereby obtaining the deformation trend of the bellows main body 1 and the required collected stress data, without setting a sensor array in the bellows main body 1, saving costs and saving subsequent data processing steps;

[0036] In addition, a displacement sensor for detecting the sliding of the slide rod 3 may be provided inside the installation box 2, and the deformation degree of the bellows body 1 may be estimated by the data obtained by the displacement sensor. If the sliding distance of the slide rod 3 is long, it indicates that the deformation degree of the bellows body 1 is high.

[0037] Reference Figure 1-Figure 3 , about how to install the installation box 2 on the corrugated pipe body 1, specifically:

[0038] A threaded rod 21 is connected to the upper surface of the arc plate 23 . The threaded rod 21 penetrates the top wall of the bellows body 1 . Two nuts 22 are threadedly connected to the threaded rod 21 . The two nuts 22 abut against the inner wall and the outer wall of the bellows body 1 , respectively.

[0039] When installing the installation box 2 on the corrugated pipe body 1, a hole is drilled at the top position of the middle section of the corrugated pipe body 1 and the threaded rod 21 is passed through the drilled hole. The lower nut 22 is installed on the threaded rod 21 when the threaded rod 21 passes through the drilled hole. After the threaded rod 21 passes through the hole, the upper nut 22 is tightened on the threaded rod 21, so that the two nuts 22 are respectively located on the inner and outer sides of the corrugated pipe body 1, thereby fixing the installation box 2 on the corrugated pipe body 1. In addition, the threaded rod 21 and the nut 22 can be connected to the corrugated pipe body 1 instead of expansion wire.

[0040] Reference Figure 3-Figure 9 , how to prevent the elasticity of the first spring 33 from declining, specifically:

[0041] Two sliding seats 41 are symmetrically connected in the installation box 2, and two sliders 46 are symmetrically connected to the upper surface of the support plate 4. A cavity is opened in the two sliding seats 41, and the side walls of the two sliders 46 are respectively fitted with the inner walls of the two cavities. After the slide rod 3 moves up or down, the slider 46 moves up or down relative to the sliding seat 41 so that the first spring 33 recovers to a length close to the initial length in the unstretched state.

[0042] The support plate 4 is connected to a micro air pump 5, which is connected to an air injection pipe 51, which is connected to the cavity, and is connected to an exhaust pipe 54, and an electromagnetic valve 53 is arranged on the air injection pipe 51 between the cavity and the exhaust pipe 54, and a pressure valve 55 is arranged on the exhaust pipe 54; after the limit plate 32 moves down to squeeze the second pressure-sensitive switch 44, the electromagnetic valve 53 is opened and the micro air pump 5 is started, so that air is filled in the cavity so that the slider 46 drives the support plate 4 to move down, and the support plate 4 moves down until the first spring 33 recovers to a state close to the initial state of not being fully stretched. When the length of the state is reached, the pressure in the cavity increases to the discharge value of the pressure valve 55, and, after the limit plate 32 moves up to squeeze the first pressure-sensitive switch 43, the solenoid valve 53 opens and the micro air pump 5 starts, so that the micro air pump 5 extracts the air in the cavity until a negative pressure is generated in the cavity so that the pressure difference exceeds the pressure value of the pressure valve 55, and then the external air enters the exhaust pipe 54, so that the slider 46 drives the support plate 4 to move up to the first spring 33 to restore the length close to the initial length in the not fully stretched state, the micro air pump 5 stops running, and the solenoid valve 53 is closed after the pressure valve 55 is closed.

[0043] The gas injection pipe 51 is connected to the two cavities, and a first diverter valve 52 is provided at the connection between the gas injection pipe 51 and the micro air pump 5 .

[0044] Both sliding seats 41 are connected to a connecting seat 45 that can be vertically slidably arranged, and a vertical rod 421 is vertically slidably connected to the connecting seat 45. The bottom of the vertical rod 421 is connected to a mounting frame 42, and a second spring 422 is connected between the mounting frame 42 and the connecting seat 45. The first pressure-sensitive switch 43 and the second pressure-sensitive switch 44 are respectively connected to the two connecting seats 45.

[0045] The two connection seats 45 are both provided with grooves, and the two sides of the limit plate 32 are respectively engaged in the two grooves, and the first pressure-sensitive switch 43 and the second pressure-sensitive switch 44 are respectively connected to the top wall and the bottom wall of the two grooves.

[0046] A sliding groove cooperating with the connecting seat 45 is provided on the side of the sliding seat 41, and a rectangular frame 6 is slidably connected in the sliding groove. The sliding direction of the rectangular frame 6 is perpendicular to the connecting seat 45, and anti-slip grooves are provided on the contact surfaces of the rectangular frame 6 and the connecting seat 45. When the rectangular frame 6 approaches or moves away from the connecting seat 45, the connecting seat 45 can be locked or unlocked on the sliding seat 41; when the exhaust pipe 54 discharges air, the rectangular frame 6 slides in the direction away from the connecting seat 45, and, when the exhaust pipe 54 stops discharging air, the rectangular frame 6 slides in the direction close to the connecting seat 45; when the connecting seat 45 is locked on the sliding seat 41, the limit plate 32 can drive the mounting frame 42 to slide relative to the connecting seat 45, and, when the connecting seat 45 is unlocked from the sliding seat 41, the limit plate 32 can drive the connecting seat 45 to slide relative to the sliding seat 41.

[0047] A rectangular plate 61 is connected to the sliding seat 41, and the rectangular plate 61 is located in the middle of the rectangular frame 6. A wedge 62 and a third spring 63 are connected to the two sides of the rectangular plate 61 respectively. A piston cylinder 67 is connected to the sliding seat 41, and the piston cylinder 67 is connected to the air guide pipe 65. A piston rod 68 is slidably connected to the piston cylinder 67 through a fourth spring 69. The wedge 62 is connected to the end of the piston rod 68. The wedge 62 and the piston rod 68 are jointly provided with an air hole 64 connecting the piston cylinder 67 and the external space. Two inclined surfaces are symmetrically arranged on the wedge 62, and when the wedge 62 slides, the rectangular frame 6 can be pushed away from the connecting seat 45 by sliding the inclined surfaces in the opposite direction; when the air guide pipe 65 injects or exhausts air into the piston cylinder 67, the piston rod 68 drives the wedge 62 to slide.

[0048] There are four piston cylinders 67 , and every two of the four piston cylinders 67 are symmetrically connected to the two sides of the sliding seat 41 . The air duct 65 is connected to the two piston cylinders 67 on the same side, and a second diverter valve 66 is provided at the connection between the exhaust pipe 54 and the air duct 65 .

[0049] Since the driving force for activating the two stress sensors comes directly from the elastic force of the first spring 33, in order to ensure the service life of the first spring 33, it is necessary to ensure that the deformation degree of the first spring 33 is not too large or the large deformation time does not last too long. Therefore, after the stress sensor sends data, the position of the support plate 4 is adjusted again so that the first spring 33 can continue to be in an incompletely stretched state. Therefore, after the stress sensor sends the stress data, the control system receives the stress data, and then the control system controls the solenoid valve 53 to open, and the micro air pump 5 is started at the same time. If the slide bar 3 has moved down, then the first spring 33 is in a state of being not fully stretched. The first spring 33 is in a further stretched state, so that the tension applied by the first spring 33 to the support plate 4 increases. At this time, the micro air pump 5 pumps air into the cavity of the sliding seat 41, so that the slider 46 moves downward relative to the sliding seat 41. At this time, the support plate 4 moves downward, so that the first spring 33 can be shortened, and there is friction between the slider 46 and the inner wall of the cavity. This friction can be generated by setting a sealing ring between the two. The friction makes the support plate 4 have a sliding resistance relative to the sliding seat 41, so that the cavity in the sliding seat 41 can have a pressure higher than the atmospheric pressure. When the first spring 33 returns to When approaching the initial stretched state, the pressure value in the sliding seat 41 can break through the restriction of the pressure valve 55, so that the air is discharged from the exhaust pipe 54, so that the pressure in the cavity is maintained, and then the position of the support plate 4 does not change at this time. In addition, if the slide bar 3 has moved up, the length of the first spring 33 is shortened compared with the original state, so that the tension applied by the first spring 33 to the support plate 4 is reduced, and the control system controls the solenoid valve 53 to open. At this time, the micro air pump 5 starts and extracts the air in the cavity of the sliding seat 41, so that the slider 46 moves up relative to the sliding seat 41. At this time, the support plate 4 moves up, so that the first spring 33 can move again. The first spring 33 is stretched for the first time, and the friction between the slider 46 and the inner wall of the cavity causes a sliding resistance between the support plate 4 and the sliding seat 41, so that the cavity pressure in the sliding seat 41 can be lower than the atmospheric pressure at this time, and when the first spring 33 returns to a state close to the initial stretching state, the negative pressure value in the sliding seat 41 can break through the restriction of the pressure valve 55, so that air enters from the exhaust pipe 54, so that the pressure in the cavity is maintained, and then the position of the support plate 4 does not change at this time, so that the first spring 33 can return to a stretching state close to the initial state, thereby ensuring the service life of the first spring 33;

[0050] To ensure that the position of the mounting frame 42 can follow the movement of the limit plate 32, the connecting seat 45 also moves synchronously when the support plate 4 moves. In addition, the mounting frame 42 and the connecting seat 45 are elastically connected to ensure that the limit plate 32 applies pressure to any pressure-sensitive switch while the mounting frame 42 moves with the limit plate 32, ensuring that the movement of the limit plate 32 is not interfered with.

[0051] The process of releasing the restriction of the connecting seat 45 is as follows: when the air guide pipe 65 injects air into the piston cylinder 67, the air is discharged through the air hole 64, and the diameter of the air hole 64 is small, so that the injection speed of the air is greater than the discharge speed, and then a positive pressure is generated in the piston cylinder 67, so that the piston rod 68 extends, pushing the wedge block 62 to slide, so that the inclined surface in the opposite direction of the sliding of the wedge block 62 pushes the rectangular frame 6, so that the rectangular frame 6 overcomes the elastic force of the third spring 63 and slides in the direction away from the connecting seat 45, thereby releasing the limit on the connecting seat 45. At this time, the connecting seat 45 can slide relative to the sliding seat 41 until the second spring 422 is in a state of not being stretched or compressed and the connecting seat 45 is no longer relative to the sliding seat 41. When the sliding seat 41 slides and the connecting seat 45 is unlocked, since the mounting frame 42 is engaged with the limiting plate 32, the first spring 33 is still subjected to the pulling force of the mounting frame 42, the connecting seat 45, the vertical rod 421 and the second spring 422. Therefore, the micro air pump 5 continues to operate, so that the inaccurate stretching length of the first spring 33 caused by the locking of the connecting seat 45 is corrected, so that the first spring 33 is restored to a length close to the initial state to ensure that it can provide enough force for the sliding rod 3 to slide. Then the micro air pump 5 stops operating, the fourth spring 69 drives the wedge block 62 to reset, and the third spring 63 drives the rectangular frame 6 to reset, so that the connecting seat 45 is limited again.

[0052] When the air guide tube 65 draws air into the piston cylinder 67, the air enters through the air hole 64, and the diameter of the air hole 64 is small, so the air extraction speed in the piston cylinder 67 is greater than the speed at which the external air enters the piston cylinder 67 through the air hole 64, and then negative pressure is generated in the piston cylinder 67, causing the piston rod 68 to shorten, pulling the wedge block 62 to slide, so that the inclined surface in the opposite direction of the sliding of the wedge block 62 pushes the rectangular frame 6, and the subsequent process is the same as the action after the piston rod 68 is extended.

[0053] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A force monitoring device for a large-diameter steel corrugated pipe, comprising a mounting box (2), wherein the mounting box (2) is connected to the top wall of the middle part of the corrugated pipe body (1), characterized in that: An arc-shaped plate (23) that fits with the inner wall of the bellows body (1) is arranged on the contact surface between the installation box (2) and the bellows body (1); a support plate (4) is connected inside the installation box (2); a slide rod (3) is vertically penetrated through the middle of the support plate (4) and is slidably connected thereto; a U-shaped frame (31) is connected to the top of the slide rod (3); a limit plate (32) is connected to the bottom of the slide rod (3); a first spring (33) is connected between the limit plate (32) and the support plate (4); a first stress sensor (431) and a second stress sensor (441) are symmetrically connected inside the installation box (2); a first pressure-sensitive switch (43) for controlling the first stress sensor (431) and a second pressure-sensitive switch (44) for controlling the second stress sensor (441) are respectively arranged at the upper and lower parts of the limit plate (32); When the installation box (2) is installed on the bellows body (1), the inner wall of the bellows body (1) is in contact with the two supporting points at the top of the U-shaped frame (31) and the upper surface of the arc plate (23), and the first spring (33) is in an incompletely stretched state. When the bellows body (1) is subjected to squeezing forces from both sides, the inner walls of the bellows body (1) located on both sides of the installation box (2) are moved closer to each other, so that the U-shaped frame (31) is pushed downward relative to the installation box (2), and the The first spring (33) is further stretched and the limit plate (32) squeezes the second pressure-sensitive switch (44), and when the bellows body (1) is subjected to upper squeezing force, the top of the bellows body (1) collapses, so that the inner walls of the bellows body (1) on both sides of the installation box (2) move away from each other, so that the first spring (33) is elastically released and contracts, so that the U-shaped frame (31) moves upward, so that the limit plate (32) squeezes the first pressure-sensitive switch (43).

2. The force monitoring device for a large-diameter steel bellows according to claim 1 is characterized in that: The upper surface of the arc-shaped plate (23) is connected to a threaded rod (21), the threaded rod (21) passes through the top wall of the bellows body (1), and two nuts (22) are threadedly connected to the threaded rod (21), and the two nuts (22) are respectively in contact with the inner wall and the outer wall of the bellows body (1).

3. The force monitoring device for a large-diameter steel bellows according to claim 2 is characterized in that: Two sliding seats (41) are symmetrically connected inside the installation box (2), and two sliders (46) are symmetrically connected to the upper surface of the support plate (4). A cavity is provided inside the two sliding seats (41), and the side walls of the two sliders (46) are respectively in contact with the inner walls of the two cavities. After the sliding rod (3) moves up or down, the slider (46) moves up or down relative to the sliding seat (41) so that the first spring (33) recovers to a length close to the initial length in an unstretched state.

4. The force monitoring device for a large-diameter steel bellows according to claim 3 is characterized in that: The support plate (4) is connected to a micro air pump (5), the micro air pump (5) is connected to an air injection pipe (51), the air injection pipe (51) is communicated with the cavity, the air injection pipe (51) is connected to an exhaust pipe (54), an electromagnetic valve (53) is provided on the air injection pipe (51) between the cavity and the exhaust pipe (54), and a pressure valve (55) is provided on the exhaust pipe (54); After the limit plate (32) moves downward to squeeze the second pressure-sensitive switch (44), the solenoid valve (53) is opened and the micro air pump (5) is started, so that air is filled into the cavity, causing the slider (46) to drive the support plate (4) to move downward. When the support plate (4) moves downward to a length close to the initial length of the first spring (33) in an incompletely stretched state, the pressure in the cavity increases to the discharge value of the pressure valve (55). After the limit plate (32) moves upward to squeeze the first pressure-sensitive switch (43), the pressure in the cavity increases to a discharge value of the pressure valve (55). The solenoid valve (53) is opened and the micro air pump (5) is started, so that the micro air pump (5) draws air from the cavity until negative pressure is generated in the cavity so that the pressure difference exceeds the pressure value of the pressure valve (55) and external air enters the exhaust pipe (54), so that the slider (46) drives the support plate (4) to move upward until the first spring (33) recovers to a length close to the initial length in an incompletely stretched state, the micro air pump (5) stops running, and the solenoid valve (53) is closed after the pressure valve (55) is closed.

5. The force monitoring device for a large-diameter steel bellows according to claim 4 is characterized in that: The gas injection pipe (51) is in communication with the two cavities, and a first diverter valve (52) is provided at the connection between the gas injection pipe (51) and the micro air pump (5).

6. The force monitoring device for a large-diameter steel bellows according to claim 5 is characterized in that: The two sliding seats (41) are both connected to a connecting seat (45) that can be vertically slidably arranged, and the connecting seat (45) is vertically slidably connected to a vertical rod (421), and the bottom of the vertical rod (421) is connected to a mounting frame (42), and a second spring (422) is connected between the mounting frame (42) and the connecting seat (45), and the first pressure-sensitive switch (43) and the second pressure-sensitive switch (44) are respectively connected to the two connecting seats (45).

7. The force monitoring device for a large-diameter steel bellows according to claim 6 is characterized in that: The two connection seats (45) are each provided with a groove, the two sides of the limit plate (32) are respectively snapped into the two grooves, and the first pressure-sensitive switch (43) and the second pressure-sensitive switch (44) are respectively connected to the top wall and the bottom wall of the two grooves.

8. The force monitoring device for a large-diameter steel bellows according to claim 7 is characterized in that: The side of the sliding seat (41) is provided with a sliding groove matched with the connecting seat (45), and a rectangular frame (6) is slidably connected in the sliding groove. The sliding direction of the rectangular frame (6) is perpendicular to the sliding direction of the connecting seat (45). The contact surfaces of the rectangular frame (6) and the connecting seat (45) are both provided with anti-slip grooves. When the rectangular frame (6) approaches or moves away from the connecting seat (45), the connecting seat (45) can be locked or unlocked on the sliding seat (41); When the exhaust pipe (54) discharges air, the rectangular frame (6) slides in a direction away from the connection seat (45); and when the exhaust pipe (54) stops discharging air, the rectangular frame (6) slides in a direction close to the connection seat (45); When the connecting seat (45) is locked to the sliding seat (41), the limiting plate (32) can drive the mounting frame (42) to slide relative to the connecting seat (45); and when the connecting seat (45) is unlocked from the sliding seat (41), the limiting plate (32) can drive the connecting seat (45) to slide relative to the sliding seat (41).

9. The force monitoring device for a large-diameter steel corrugated pipe according to claim 8, characterized in that: A rectangular plate (61) is connected to the sliding seat (41), and the rectangular plate (61) is located in the middle of the rectangular frame (6). A wedge block (62) and a third spring (63) are connected to two sides of the rectangular plate (61) respectively. A piston cylinder (67) is connected to the sliding seat (41), and the piston cylinder (67) is communicated with the air guide pipe (65). A piston rod (68) is slidably connected to the piston cylinder (67) through a fourth spring (69). The wedge block (62) is connected to the end of the piston rod (68). The wedge block (62) and the piston rod (68) are jointly provided with an air hole (64) that connects the piston cylinder (67) and the external space. The wedge block (62) is symmetrically provided with two inclined surfaces, and when the wedge block (62) slides, the rectangular frame (6) can be pushed away from the connecting seat (45) through the inclined surfaces in the opposite direction of the sliding. When the air guide pipe (65) injects or exhausts air into the piston cylinder (67), the piston rod (68) drives the wedge block (62) to slide.

10. The force monitoring device for a large-diameter steel corrugated pipe according to claim 9, characterized in that: The number of the piston cylinders (67) is four, and every two of the four piston cylinders (67) are symmetrically connected to the two sides of the sliding seat (41), the air guide pipe (65) is connected to the two piston cylinders (67) on the same side, and a second diverter valve (66) is provided at the connection between the exhaust pipe (54) and the air guide pipe (65).

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