A movable joint structure between bite jack pipes

Abstract

The embodiment of the present application discloses a movable joint structure between interlocking jacking pipes, which can solve the problem of collision interference or gap caused by construction errors when the interlocking jacking pipes are pushed forward. The movable joint structure between interlocking jacking pipes provided in the embodiment of the present application includes a first jacking pipe and a second jacking pipe that are movably connected side by side, the first jacking pipe has a connecting opening, the connecting opening extends along the extension direction of the first jacking pipe, the second jacking pipe extends into the connecting opening and is limited by the connecting opening. The present application implements a movable joint structure of an interlocking jacking pipe for excavating a tunnel.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of tunnel engineering, and in particular to a movable joint structure between interlocking jacking pipes. Background Art

[0002] When excavating a large-section dark-cut tunnel, the pipe curtain structure method is often used. The pipe curtain structure method is to first use a pipe jacking machine to construct a pipe curtain formed by several steel pipes in the soil layer, then stop the water between the pipe curtains, and then break the steel pipes horizontally to form a horizontally connected space. After that, reinforced concrete is poured in the connected space to form the main structure of the tunnel, and finally the soil inside the main structure of the tunnel is excavated. The traditional pipe curtain structure method is to excavate and jack the jacking pipe into the soil layer individually. At present, a method has been developed to connect multiple pipes together as an interlocking jacking pipe and excavate and jack into the soil layer simultaneously. However, when using the pipe curtain structure method to excavate a tunnel, there are usually errors in the construction. The interlocking jacking pipe cannot be accurately pushed forward in the predetermined direction, which will cause collisions and interference between adjacent interlocking jacking pipes, affecting the construction progress; or gaps will be generated, threatening construction safety. Summary of the invention

[0003] In order to solve the above problems, an embodiment of the present application provides a movable joint structure between bite jacking pipes, which has the following advantages: it can make up for the defects of adjacent bite jacking pipes due to construction errors, and can solve the problem of collision interference or gap generation when the bite jacking pipes are pushed forward.

[0004] In order to achieve the above-mentioned purpose, the technical solution of the embodiment of the present application is implemented as follows:

[0005] The embodiment of the present application provides a movable joint structure between interlocking top pipes, comprising a first top pipe and a second top pipe connected side by side, wherein the first top pipe has a connection opening, and the direction of the connection opening extends along the extension direction of the first top pipe. The second top pipe extends into the connection opening and is limited by the connection opening.

[0006] In the movable joint structure between the interlocking top tubes provided in the embodiment of the present application, a first top tube and a second top tube are included. A connecting opening is provided on the first top tube, and the direction of the connecting opening extends along the extension direction of the first top tube, and runs through the entire length of the first top tube; and the size of the connecting opening of the first top tube is determined according to the size of the part of the structure of the second top tube extending into the connecting opening. The second top tube can extend into the connecting opening, so that the second top tube can move relative to the first top tube at the position of the connecting opening, and the second top tube is limited by the connecting opening, which plays a function of limiting the movement of the second top tube at the position of the connecting opening, and avoiding the second top tube from having a large movement, so that the second top tube is disengaged from the connecting opening.

[0007] Through such an arrangement, the second jacking pipe can move relative to the first jacking pipe at the connecting opening. When excavating and jacking into the soil layer, when there is an error in the advancing direction, the second jacking pipe can move in the error direction relative to the first jacking pipe, thereby compensating for the defects caused by the error between adjacent interlocking jacking pipes. Therefore, the problem of collision interference or gap generation when the interlocking jacking pipes are jacked forward can be solved.

[0008] Furthermore, the opening size of the connecting opening is greater than the height of the structure of the second top pipe extending into the connecting opening.

[0009] Furthermore, an extension portion is provided at one end of the second jack pipe extending into the connecting opening, and the extension portion is used to prevent the second jack pipe from being disengaged from the connecting opening.

[0010] Furthermore, a mounting plate is provided at the connection opening on the first top pipe, and a water stopping device is provided on the mounting plate.

[0011] Furthermore, the water-stopping device includes a curtain rubber plate or a rubber pad; one end of the curtain rubber plate is fixedly connected to the mounting plate, and the other end is overlapped on the second top pipe; the rubber pad is arranged between the mounting plate and the second top pipe, and the end of the rubber pad close to the second top pipe is larger than the other end close to the first top pipe.

[0012] Furthermore, a plurality of mounting plates are arranged at the connection opening on the first top pipe, and any one of a cord rubber plate or a rubber pad is arranged on each mounting plate.

[0013] Furthermore, a cavity is formed between two adjacent rubber sheets or rubber pads, and grease is poured into the cavity.

[0014] Furthermore, a plurality of partitions are arranged in the cavity along its extension direction, and flexible rubber plates are arranged at the partitions.

[0015] Furthermore, a plurality of tensioning devices are arranged at intervals on the first top pipe along its extending direction, and both ends of the tensioning devices are respectively connected to positions on the first top pipe close to the connecting opening, so as to apply a force to shrink the connecting opening. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of a movable joint structure between bite jack pipes provided in an embodiment of the present application;

[0017] Figure 2 A partially enlarged schematic diagram of a mounting plate and a rubber sheet of a movable joint structure between bite jack pipes provided in an embodiment of the present application;

[0018] Figure 3 A partially enlarged schematic diagram of a mounting plate and a rubber pad of a movable joint structure between bite jack pipes provided in an embodiment of the present application;

[0019] Figure 4 Schematic diagram of a two-way water-stopping device of a movable joint structure between bite jack pipes provided in an embodiment of the present application Figure 1 ;

[0020] Figure 5 Schematic diagram of a two-way water-stopping device of a movable joint structure between bite jack pipes provided in an embodiment of the present application Figure 2 ;

[0021] Figure 6 A schematic diagram of pouring grease into a cavity between two water-stopping devices of a movable joint structure between bite jack pipes provided in an embodiment of the present application;

[0022] Figure 7 A schematic diagram of a partition provided in a cavity between two water-stopping devices of a movable joint structure between bite jack pipes provided in an embodiment of the present application;

[0023] Figure 8 An AA view showing a partition provided in a cavity between two water-stopping devices of a movable joint structure between interlocking jacking pipes provided in an embodiment of the present application.

[0024] Reference numerals:

[0025] 1-first top tube; 2-second top tube; 21-second top tube body; 22-extension portion; 3-connection opening; 4-mounting plate; 5-water-stop device; 51-cord rubber sheet; 52-rubber pad; 6-cavity; 7-grease; 8-partition; 81-connection plate; 82-flexible rubber sheet; 9-tensioning device. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the specific technical solution of the present application will be further described in detail below in conjunction with the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application, but are not used to limit the scope of the present application.

[0027] In the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more.

[0028] In addition, in the embodiments of the present application, directional terms such as "up", "down", "left" and "right" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to the changes in the orientation of the components in the drawings.

[0029] In the embodiments of the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0030] In the embodiments of the present application, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0031] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0032] The embodiment of the present application provides a movable joint structure between interlocking jacking pipes, which is used for connecting interlocking jacking pipes. Interlocking jacking pipes are one of the pipe curtain structures commonly used in tunnel excavation. Connecting multiple interlocking jacking pipes can form the main structure of the outer edge of the tunnel. Due to the influence of objective construction errors during the construction process, the interlocking jacking pipes cannot be pushed forward accurately along the predetermined direction, so that adjacent interlocking jacking pipes will collide and interfere when pushing forward, affecting the construction progress; or there will be gaps between adjacent pipe curtain structures, threatening construction safety.

[0033] In view of this, an embodiment of the present application provides a movable joint structure between bite jacking tubes, which can compensate for the defects caused by errors when adjacent bite jacking tubes are pushed forward, and can solve the problem of collision interference or gap generation when the bite jacking tubes are pushed forward.

[0034] In order to more clearly illustrate the movable joint structure between the bite top pipes provided in the embodiment of the present application, a detailed description is given below with reference to the accompanying drawings.

[0035] Reference Figure 1 , a movable joint structure between interlocking jacking pipes provided in an embodiment of the present application comprises: a first jacking pipe 1 and a second jacking pipe 2, and the first jacking pipe 1 and the second jacking pipe 2 are connected side by side and arranged along the extension direction of the tunnel, and the first jacking pipe 1 is provided with a connection opening 3 on a side close to the second jacking pipe 2. It should be noted that in a movable joint structure between interlocking jacking pipes provided in an embodiment of the present application, the first jacking pipe 1 and the second jacking pipe 2 are a general concept, and the first jacking pipe 1 and the second jacking pipe 2 do not specifically refer to "tube" structures, but can also be box-shaped structures or structures of other shapes. In addition, the first jacking pipe 1 and the second jacking pipe 2 can be a part of the interlocking jacking pipe, for example, it can be the structure of one end of the adjacent interlocking jacking pipe itself, which is processed as a movable joint structure; it can also be a separately arranged movable joint structure, and the two ends of the movable joint structure are respectively connected to the jacking pipe structure to be interlocked and connected, for example, a box-shaped structure is arranged at one end of the tubular interlocking jacking pipe, so that the box-shaped structure is connected to the adjacent first jacking pipe 1 as a part of the second jacking pipe 2, and the embodiment of the present application does not limit this. The direction of the connecting opening 3 provided on the first jacking pipe 1 extends along the extension direction of the first jacking pipe 1 and extends to the entire length of the first jacking pipe 1, so that the second jacking pipe 2 can move along the connecting opening 3 during the entire jacking process, the second jacking pipe 2 extends into the connecting opening 3, and the connecting opening 3 limits the second jacking pipe 2 therein, so that when the second jacking pipe 2 moves in the connecting opening 3 relative to the first jacking pipe 1, it cannot be disengaged from the connecting opening 3.

[0036] Through the above-mentioned arrangement, the movable joint structure between the interlocking jacking pipes provided in the embodiment of the present application can enable the second jacking pipe 2 to move relative to the first jacking pipe 1 in the connecting opening 3. When there is an error in the forward excavation and jacking of the interlocking jacking pipe, the second jacking pipe 2 can move in the connecting opening 3 in the direction of the error, thereby compensating for the defects caused by the error between adjacent interlocking jacking pipes and solving the problem of collision interference or gap generation when the interlocking jacking pipe is jacked forward.

[0037] It should be noted that the opening size of the connection opening 3 is larger than the height of the structure where the second jacking pipe 2 extends into the connection opening 3. When confirming the opening size of the connection opening 3, it is necessary to consider the size of the structure where the second jacking pipe 2 extends into the connection opening 3 and the construction error of the interlocking jacking pipe when excavating and jacking forward, and consider a certain margin. For example, when the construction accuracy of the jacking equipment used is high and the construction error is small, the opening size of the connection opening 3 can be appropriately reduced; when the construction accuracy of the jacking equipment used is low and the construction error is large, the opening size of the connection opening 3 should be appropriately increased to ensure that when the interlocking jacking pipe is jacked forward, the second jacking pipe 2 and the connection opening 3 maintain sufficient clearance in their height direction to avoid collision and interference between the first jacking pipe 1 and the second jacking pipe 2. However, it should also be noted that the opening size of the connection opening 3 should not be too large to avoid the second jacking pipe 2 from detaching from the connection opening 3. Reference Figure 1 The mark Y in the figure is the opening size of the connecting opening 3 and the height difference of one side of the structure where the second top pipe 2 extends into the connecting opening 3.

[0038] On this basis, the second top pipe 2 is provided with an extension portion 4 on the structure extending into the connection opening 3. The function of the extension portion 4 is to prevent the second top pipe 2 from sliding out of the connection opening 3 when the second top pipe 2 is excavated and pushed forward. The extension portion 4 of the second top pipe 2 can be a part of the second top pipe 2 itself extending into the connection opening 3 as the extension portion 4; or it can be other structures additionally connected to the second top pipe 2, which is not limited in the embodiments of the present application. Figure 1 , the mark X in the figure is the length of the extension portion 4 extending into the connection opening 3 provided on the second jacking pipe 2. It should be noted that the length of the extension portion 4 extending into the connection opening 3 needs to be determined by considering the construction error when the bite jacking pipe is pushed forward, and a certain margin is considered.

[0039] It should be noted that the opening size of the above-mentioned connection opening 3 and the height difference of the second jacking pipe 2 extending into the connection opening 3 and the length of the extension portion 4 provided on the second jacking pipe 2 and extending into the connection opening 3 need to be determined by considering the size and construction error of the structure of the second jacking pipe 2 extending into the connection opening 3, and a certain margin, with the principle that the second jacking pipe 2 can move relative to the first jacking pipe 1 in the connection opening 3 when jacking forward, and cannot escape from the connection opening 3. In this way, the second jacking pipe 2 can move relative to the first jacking pipe 1 in the connection opening 3 during the entire jacking process, and the second jacking pipe 2 will not escape from the connection opening 3.

[0040] Further, refer to Figure 1 and Figure 2, a mounting plate 4 is provided at the connection opening 3 on the first top pipe 1, and the mounting plate 4 is arranged on both sides of the connection opening 3 and arranged in the entire length direction of the first top pipe 1. It should be noted that the mounting plate 4 can be formed by bending a portion of the wall of the first top pipe 1 near the connection opening 3 by external force, or it can be formed by connecting another plate-like structure to the first top pipe 1, and this embodiment of the application is not limited to this. Figure 2 A water-stopping device 5 is provided between the mounting plate 4 and the second jacking pipe 2. The water-stopping device 5 can prevent external water from penetrating into the tunnel through the gap between the first jacking pipe 1 and the second jacking pipe 2 at the connecting opening 3, thereby ensuring the safety during construction inside the tunnel.

[0041] On this basis, refer to Figure 2 and Figure 3 The water stop device 5 includes a rubber sheet 51 or a rubber pad 52. Figure 2 , one side of the cord rubber sheet 51 is fixedly connected to the mounting plate 4, and the other side is overlapped on the second top tube 2, and the cord rubber sheet 51 extends along the mounting plate 4 to the entire length of the first top tube 1. It should be noted that the cord rubber sheet 51 can be fixed to the mounting plate 4 by connecting bolts, or can be bonded to the mounting plate 4 by adhesive, or fixedly connected to the mounting plate 4 by other means, and the embodiment of the present application is not limited to this. The height of the cord rubber sheet 51 is greater than the gap between the bottom of the mounting plate 4 and the second top tube 2, and the cord rubber sheet 51 is bent and extended along the upper surface of the second top tube 2 toward the outside of the first top tube 1, so that when the pressure of the external water acts on the cord rubber sheet 51, the cord rubber sheet 51 can be more closely attached to the upper surface of the second top tube 2, so as to better play the sealing function of the cord rubber sheet 51. In addition, the cord rubber sheet 51 has a cord layer in the middle, which can make the cord rubber sheet 51 have high tensile strength, high pressure bearing capacity, and has the advantages of aging resistance and easy processing, and is very suitable for use as a water-stopping material in tunnel excavation projects.

[0042] Reference Figure 3The water-stop device 5 provided at the connection opening 3 also includes a rubber pad 52, which is provided between the mounting plate 4 and the second top pipe 2 to play a sealing role. The size of the rubber pad 52 at one end close to the second top pipe 2 is larger than the size at the other end close to the first top pipe 1. The cross section of the rubber pad 52 forms a right-angled trapezoidal shape, with the right-angled side in contact with the upper surface of the second top pipe 2 and the beveled side in contact with the mounting plate 4. The position where the mounting plate 4 contacts the rubber pad 52 can be processed into an inclined surface corresponding to the beveled side of the rubber pad 52, so that the contact area between the mounting plate 4 and the rubber pad 52 can be increased, and the corners of the mounting plate 4 can be prevented from contacting the rubber pad 52, which may damage the rubber pad 52 and cause sealing failure. The right-angled trapezoidal structure of the rubber pad 52, which is similar to a wedge structure, has the advantage of being self-sealing. When the larger end of the rubber pad 52 is subjected to external water pressure, it tends to move toward the smaller end, so that the rubber pad 52 is in closer contact with the second top pipe 2 and the mounting plate 4. The greater the external water pressure on the rubber pad 52, the closer the contact with the second top pipe 2 and the mounting plate 4, and the better the sealing effect. It should be noted that the size of the rubber pad 52 should be appropriate, so that the middle part of the rubber pad 52 is preferably below the mounting plate 4, so as to prevent the rubber pad 52 from slipping out of the gap between the mounting plate 4 and the second top pipe 2 when it is greatly deformed.

[0043] Further, refer to Figure 4 and Figure 5 In order to further ensure the sealing effect of the water stop device 5, a plurality of mounting plates 4 are provided at the connection opening 3 on the first top pipe 1, and a cord rubber plate 51 or a rubber pad 52 is provided on each mounting plate 4. Figure 4 , is a schematic diagram of two mounting plates 4 and two cord rubber plates 51, wherein the mounting plate 4 near the second top tube 2 is processed from the tube wall of the first top tube 1 itself, and the mounting plate 4 near the first top tube 1 is an additional plate structure fixedly connected to the first top tube 1 as the mounting plate 4. Figure 5 , is a schematic diagram of a combined seal of two mounting plates 4, a cord rubber plate 51 and a rubber pad 52. Figure 4 and 5 In the embodiment of the present invention, two or more mounting plates 5 are provided, and one of a cord rubber plate 51 or a rubber pad 52 is provided on each mounting plate 4.

[0044] On this basis, refer to Figure 4 and Figure 5A cavity 6 is formed between two adjacent rubber sheets 51 or rubber pads 52. Grease 7 is poured into the cavity 6, and the poured grease 7 can play a sealing role to prevent external water from penetrating into the tunnel; at the same time, it can also play a lubricating role on the rubber sheets 51 or rubber pads 52 to prevent the second top pipe 2 from damaging the rubber sheets 51 or rubber pads 52 during excavation and jacking. It should be noted that by pouring grease 7 into the cavity 6 and making the pressure of the grease 7 equal to or slightly greater than the pressure of the external water, the rubber sheets 51 or rubber pads 52 on the side close to the first top pipe 1 can be tightly attached to the upper surface of the second top pipe 2, thereby ensuring the sealing here; at the same time, the pressure of the grease 7 at the rubber sheets 51 or rubber pads 52 on the other side is balanced with the pressure of the external water, or the pressure of the grease 7 is slightly greater than the pressure of the external water, so that the grease 7 has a slight outward leakage, thereby also preventing external water from penetrating into the tunnel. It should be noted that a pressure detection system can be provided to detect the pressure of external water and the pressure of the injected grease 7. For example, a pressure monitoring instrument can be provided at a position near the connecting opening 3 of the second top pipe 2, and the pressure signal can be transmitted to the outside of the excavated soil layer through a wire, so as to monitor the pressure of the external water; at the same time, a pressure detection instrument can be provided on the pipeline for injecting grease 7 to monitor the pressure of grease 7. In this way, the pressure of the external water and the pressure of the injected grease 7 can be compared, and then the pressure of the injected grease 7 can be adjusted so that the pressure of the grease 7 is equal to or slightly greater than the pressure of the external water.

[0045] It should be noted that, refer to Figure 7 and Figure 8 In order to prevent water seepage between the rubber sheet 51 or rubber pad 52 at a certain position and affect the sealing effect of the entire length, a plurality of partitions 8 are arranged in the cavity 6 along its extension direction, and a connecting plate 81 and a flexible rubber plate 82 are arranged at the partition 8, so that the cavity 6 can be divided into a plurality of relatively independent parts. Even if the rubber sheet 51 or rubber pad 52 corresponding to a certain part of the cavity 6 seeps water, it will not affect the sealing effect of the rubber sheet 51 or rubber pad 52 of the entire length. At the same time, the flexible rubber plate 82 is arranged at the partition 8, which does not affect the injection of grease 7 into the cavity 7. A connecting plate 81 is arranged at the upper part of the cavity 6, and the flexible rubber plate 82 is fixedly connected to the connecting plate 81.

[0046] It should be noted that, refer to Figure 1, multiple tensioning devices 10 are arranged at intervals along the extension direction of the first top tube 1, and the two ends of the tensioning device 10 are respectively connected to the positions of the first top tube 1 close to the connection opening 3. By operating the tensioning device 10, a tension force can be applied to the connection opening 3 to reduce the opening of the connection opening 3. By applying a pre-tightening force to the tensioning device 10, the connection opening 3 can be prevented from expanding outwards. In particular, when grease 7 is poured between two adjacent cord rubber plates 51 or rubber pads 52, the connection opening 3 has a tendency to expand outwards under the pressure of the grease 7. By applying a pre-tightening force to the connection opening 3 in advance, the connection opening 3 can be prevented from expanding outwards. The tensioning device 10 can be a chain tensioner. The chains on both sides of the chain tensioner are respectively connected to the positions on both sides of the connection opening on the first top tube 1. A handle is arranged in the middle of the chain tensioner. By operating the handle, the chains on both sides can be tightened, thereby reducing the opening of the connection opening 3. Other forms of tensioning devices 10 may also be selected, such as a turnbuckle tightener, but the embodiments of the present application are not limited thereto.

[0047] In summary, the movable joint structure between interlocking jacking pipes provided in the present application example can make up for the defects caused by errors when adjacent interlocking jacking pipes are excavated and pushed forward, and can solve the problem of collision interference or gaps when the interlocking jacking pipes are pushed forward. In addition, the movable joint structure between interlocking jacking pipes provided in the present application example is provided with a water-stopping device, which can prevent external water from seeping into the tunnel and ensure the safety of the tunnel.

[0048] The serial numbers of the embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments. The above are only preferred embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A movable joint structure between bite jack pipes, characterized in that: The invention comprises a first top pipe and a second top pipe which are movably connected side by side, wherein the first top pipe has a connection opening, the connection opening extends along the extension direction of the first top pipe, and the second top pipe extends into the connection opening and is limited by the connection opening; A mounting plate is provided at the connection opening on the first top pipe, and a water stop device is provided on the mounting plate; The water-stopping device comprises a rubber sheet or a rubber pad, one end of the rubber sheet is fixedly connected to the mounting plate, and the other end is overlapped on the second top pipe; the rubber pad is arranged between the mounting plate and the second top pipe; A plurality of mounting plates are provided at the connection opening on the first top pipe, and each mounting plate is provided with any one of a cord rubber plate or a rubber pad; A cavity is formed between two adjacent cord rubber plates or rubber pads, and grease is poured into the cavity; A plurality of partitions are arranged at intervals along the extension direction of the cavity, and a flexible rubber sheet is arranged at the partitions; A plurality of tensioning devices are arranged at intervals on the first jack pipe along its extending direction, and two ends of the tensioning devices are respectively connected to positions of the first jack pipe close to the connecting opening for applying a force to shrink the connecting opening.

2. The movable joint structure between the bite top pipes according to claim 1 is characterized in that: The opening size of the connecting opening is greater than the height of the structure in which the second top pipe extends into the connecting opening.

3. The movable joint structure between the bite top pipes according to claim 2 is characterized in that: An extension portion is provided at one end of the second jacking pipe extending into the connecting opening, and the extension portion is used to prevent the second jacking pipe from being disengaged from the connecting opening.

4. The movable joint structure between the occlusal jacking pipes according to claim 1, characterized in that: One end of the rubber pad close to the second top tube is larger than the other end close to the first top tube.

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