A tunneling machine capable of using a central screw machine to discharge slag

Abstract

The present invention relates to the field of soil or rock stratum excavation equipment, and in particular to a tunneling machine that can use a center screw machine to discharge slag. The tunneling machine includes a main machine, the main machine includes a shield, a cutter head and a main drive, the main drive includes a drive box, a screw conveyor is installed in the inner hole of the drive box through a seat flange, a spherical bearing is provided on the screw conveyor, and opposing guide rails are provided in the inner hole of the drive box. The spherical bearing is provided with an anti-twist block corresponding to the guide rail, and a limiting groove corresponding to the anti-twist block is defined between the two guide rails. The limiting groove cooperates with the anti-twist block to limit the rotation of the screw conveyor. The present invention improves the existing tunneling machine, and the limiting groove limited by the two guide rails can cooperate with the anti-twist block to achieve accurate positioning of the screw conveyor, which can solve the problem of low installation efficiency of the screw conveyor of the shield machine that uses a center screw machine to discharge slag in the prior art due to difficult positioning.

Description

Technical Field

[0001] The invention relates to the field of soil or rock stratum excavation equipment, in particular to a excavation machine capable of using a central screw machine to discharge slag. Background Art

[0002] As a full-section excavation equipment used in tunnel construction, the shield machine has been widely used in the construction of urban subway tunnels. The conventional earth pressure balance shield machine includes a main machine and a supporting system. The main machine includes a shield body, a cutterhead, a main drive, a propulsion device and a screw conveyor. The shield body is provided with a partition, the main drive is installed on the partition, the cutterhead is installed on the main drive, and a soil bin is formed between the back and the partition. The screw conveyor is installed at the bottom of the soil bin partition. The slag generated during the excavation process first enters the soil bin through the slag discharge port on the cutterhead and accumulates in the soil bin, and then is transported backward by the screw conveyor to the slag discharge device of the supporting system, and then transported out of the tunnel. Nowadays, with the complex and changeable excavation geology, conventional earth pressure balance shield machines can no longer meet the construction needs well. Unconventional earth pressure, open mode, mud water mode, and multi-mode shield machines that use a central screw conveyor to discharge slag are gradually being used due to their strong adaptability, safety, reliability, and multiple functions.

[0003] For example, an invention patent application with application publication number CN110513117A and publication date November 29, 2019 provides a dual-mode shield screw machine mode switching device and a method of use. The description of the patent application discloses a dual-mode shield machine. Different from the structure of a conventional earth pressure balance shield machine, the dual-mode shield machine has screw machine installation positions at the bottom and center of the soil bin partition. The screw conveyor can be installed in the center of the soil bin partition or on the screw machine support at the bottom of the soil bin partition according to actual working conditions.

[0004] In the dual-mode shield machine disclosed in the above patent application, when the screw conveyor is installed on the screw machine support, the installation of the screw conveyor is relatively easy because the space at the bottom of the soil bin partition in the shield body is relatively spacious. However, when installed at the center of the soil bin partition, the positioning problem of the screw conveyor will become extremely complicated because it is installed through a connecting flange and the middle position is limited. Especially in order to meet the turning requirements of the tunnel boring machine and the front end of the center screw conveyor is designed with a spherical bearing, the position where the screw conveyor is installed is basically equivalent to the diameter of the screw conveyor. There is an observation blind spot in the process of installing the screw conveyor, and the assembler cannot effectively observe this process. It is easy to find that the holes of the two are not aligned after the screw conveyor is sent to the installation position. At this time, the screw conveyor is difficult to adjust into place and can only be dismantled and reinstalled. The screw conveyor in the shield machine is large in size and extremely heavy in weight. Each dismantling and reinstallation will consume a lot of manpower and material resources, and seriously restrict the construction period. Summary of the invention

[0005] The object of the present invention is to provide a tunnel boring machine which can use a central screw machine to discharge slag, so as to solve the problem of low installation efficiency of the screw conveyor of the existing shield machine which uses a central screw machine to discharge slag due to the difficulty in positioning.

[0006] In order to solve the above problems, the tunneling machine that can use a center screw machine to discharge slag of the present invention adopts the following technical scheme: a tunneling machine that can use a center screw machine to discharge slag, including a main machine, the main machine includes a shield body, a cutter disc and a main drive, the main drive includes a drive box, a screw conveyor is installed in the inner hole of the drive box through a seat flange, the screw conveyor is provided with a joint bearing, the inner hole of the drive box is provided with opposing guide rails, the joint bearing is provided with an anti-twist block corresponding to the guide rail, and a limit groove corresponding to the anti-twist block is defined between the two guide rails, and the limit groove cooperates with the anti-twist block to limit the rotation of the screw conveyor.

[0007] Beneficial effect: The tunnel boring machine that can use a center screw machine to discharge slag of the present invention improves the existing tunnel boring machine, arranges opposing guide rails in the internal control of the drive box, and arranges anti-twist blocks corresponding to the guide rails on the joint bearings of the screw conveyor. The limiting grooves restricted by the two guide rails can cooperate with the anti-twist blocks. On the one hand, the circumferential posture of the screw conveyor during installation can be determined, and on the other hand, the screw conveyor can be prevented from being offset or twisted during the advancement process, thereby achieving accurate positioning of the screw conveyor, which can solve the problem of low installation efficiency of the screw conveyor of the existing shield machine that uses a center screw machine to discharge slag due to difficult positioning.

[0008] Furthermore, based on the opposite surfaces of the two guide rails, the guide rails include a variable spacing section at the front end, and the variable spacing sections of the two guide rails form an "eight" shape with a small front and a large back. The variable spacing sections form an "eight" shape, which can capture the screw conveyor in a larger range at the initial stage of the screw conveyor installation, has a larger position tolerance, and further facilitates the installation of the screw conveyor.

[0009] Furthermore, the top surface of the guide rail is used to support the spherical bearing. After the top surface of the guide rail is set as the supporting surface for supporting the spherical bearing, the upper and lower positions of the front end of the screw conveyor can be further positioned, further improving the smoothness of the screw conveyor when installing the screw conveyor.

[0010] Furthermore, based on the top surfaces of the two guide rails, the guide rails include a horizontal section at the front end and an inclined section at the rear end of the horizontal section, and the top surface of the inclined section is inclined downward from the back to the front. The inclined section can reduce the resistance of the screw conveyor when it is pushed forward during installation.

[0011] Furthermore, the inclined section and the variable spacing section have an overlapping portion in the front-to-back direction. The overlapping portion is arranged between the inclined section and the variable spacing section in the front-to-back direction, which can reduce the resistance of the top surface of the guide rail to the joint bearing while the distance between the variable spacing section and the anti-twist block becomes smaller and the resistance becomes larger, so that the two can compensate for each other and reduce the difficulty of advancing the screw conveyor.

[0012] Furthermore, the support surface is a transition support surface, and after the screw conveyor is installed in place, the spherical bearing is separated from the support surface. After the spherical bearing is separated from the support surface, it can avoid hindering the relative positioning between the spherical bearing and the seat flange.

[0013] Furthermore, a guide cone is provided at the front end of the joint bearing, and when the joint bearing moves to the front end of the guide rail, the guide cone extends into the center hole of the seat flange. The guide cone can play a role of relay positioning, has a simple structure and good centering ability.

[0014] Furthermore, an anti-collision block is provided in the inner hole of the drive box for limiting the screw conveyor to prevent the screw conveyor from colliding with the drive box. The anti-collision block can protect the screw conveyor and the drive box, and especially can prevent the drive box from being damaged.

[0015] Furthermore, the radial dimension of the anti-collision block of the screw conveyor is larger than the swing distance dimension when the spherical bearing is separated from the limiting groove. By setting this dimension relationship, the anti-collision block plays the role of radially constraining the spherical bearing, which can further prevent it from separating from the limiting groove restricted by the guide rail during the forward movement.

[0016] Furthermore, the tunnel boring machine also includes a segment assembler, and the rear end of the screw conveyor is mounted on the segment assembler through the cooperation of the slide rail and the slider. After the rear end of the screw conveyor is mounted on the segment assembler through the cooperation of the slide rail and the slider, the rear end of the screw conveyor can be supported by a simple structure, which is also more convenient when advancing the screw conveyor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the initial overlap state of the screw conveyor and the guide rail during the installation process of the screw conveyor in Example 1 of the tunneling machine that can use the central screw conveyor to discharge slag of the present invention;

[0018] Figure 2 yes Figure 1 Schematic diagram of the cooperation between the guide rail and the anti-twist block;

[0019] Figure 3 yes Figure 1 A side view of the guide rail assembly in FIG.

[0020] Figure 4 yes Figure 3 A-direction view;

[0021] Figure 5 yes Figure 1 A cross-sectional view of a spherical plain bearing in FIG.

[0022] Figure 6 yes Figure 1 Schematic diagram of the installation of anti-torsion blocks on spherical plain bearings;

[0023] Figure 7 It is a schematic diagram of overlapping the inclined section of the screw conveyor and the guide rail during the installation of the screw conveyor in Example 1 of the tunneling machine that can use a central screw conveyor to discharge slag of the present invention;

[0024] Figure 8 yes Figure 7 Schematic diagram of the cooperation between the guide rail and the anti-twist block;

[0025] Fig. 9 It is a schematic diagram of the overlap between the screw conveyor and the seat flange during the installation of the screw conveyor in Example 1 of the tunneling machine that can use the central screw conveyor to discharge slag of the present invention;

[0026] Fig.10 yes Fig. 9 Schematic diagram of the cooperation between the guide rail and the anti-twist block;

[0027] Fig.11 It is a schematic diagram of Example 1 of the tunneling machine capable of using a central screw conveyor to discharge slag according to the present invention after the screw conveyor is installed;

[0028] Fig.12 yes Fig.11 Schematic diagram of the cooperation between the guide rail and the anti-twist block.

[0029] In the figure: 11, shield body; 111, front shield; 112, middle shield; 113, tail shield; 12, main drive; 121, drive box; 122, drive unit; 13, cutter head; 14, thrust cylinder; 15, segment assembler; 16, soil bin partition; 17, adjustment cylinder; 18, screw conveyor; 19, spherical bearing; 191, guide cone; 20, bearing flange; 21, seat flange; 22, guide rail; 221, horizontal section; 222, inclined section; 223, variable spacing section; 224, equal spacing section; 101, limit groove; 23, anti-twist block; 24, anti-collision block. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0032] It should be noted that relational terms such as "first" and "second" that may appear are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, terms such as "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements that are 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 a sentence such as "comprises a..." does not exclude the existence of other identical elements in the process, method, article or device that includes the element.

[0033] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0034] Embodiment 1 of the tunneling machine of the present invention that can use a central screw machine to discharge slag:

[0035] like Figure 1-11 As shown, the tunnel boring machine that can use a central screw machine to discharge slag of the present invention includes a main machine, and the main machine includes a shield body 11, a main drive 12, a cutter head 13, a propulsion cylinder 14 and a segment assembler 15.

[0036] The shield body 11 includes a front shield 111, a middle shield 112 and a rear shield 113, wherein the front shield 111 is provided with a soil bin partition 16, which is annular, and the outer edge of which is fixedly connected to the inner wall surface of the front shield 111, and the inner hole forms a mounting hole for mounting the main drive 12. The middle shield 112 includes a front section and a rear section, and a steering cylinder 17 is provided between the front section and the rear section. There are multiple steering cylinders 17, and the centerline direction of the front shield 111 can be changed by the cooperation of multiple steering cylinders 17, thereby realizing the steering during excavation.

[0037] The main drive 12 is installed in the mounting hole of the soil bin partition 16, and includes a drive box 121 and a drive unit 122, a transmission unit and a main bearing arranged in the drive box 121. The drive box 121 is annular, and the outer edge is fixedly connected to the inner hole wall of the soil bin partition 16, and the inner hole forms a screw machine mounting hole for installing the screw conveyor 18.

[0038] The cutterhead 13 is mounted on the drive box 121 in cooperation with the main bearing. A soil bin is formed between the back of the cutterhead 13 and the soil bin partition 16. During the excavation process, the generated slag will enter the soil bin. The front end of the propulsion cylinder 14 is connected to the front shield 111. When working, the tunnel boring machine can be driven to excavate by supporting the assembled segments backwards.

[0039] The segment assembler 15 is arranged at the rear of the main machine, and is used to grab the segments delivered by the rear supporting system and assemble them at corresponding positions. The structure and installation method of the segment assembler 15 are both existing technologies and will not be described in detail here.

[0040] A screw conveyor 18 is installed in the screw machine installation hole of the drive box 121. The screw conveyor 18 is used to discharge the slag generated during the excavation process backward from the main machine, so that the matching slag conveying device can further transport it out of the tunnel. The assembly structure between the screw conveyor and the main drive will be specifically introduced below.

[0041] In order to meet the turning requirements of the shield machine, a spherical bearing 19 is installed at the front end of the screw conveyor 18, and a bearing flange 20 is arranged on the spherical bearing 19. Correspondingly, a seat flange 21 is arranged in the screw machine mounting hole of the drive box 121. After the bearing flange 20 and the seat flange 21 are aligned, the installation of the screw conveyor 18 can be completed by fastening the bolts to fix the two. During the assembly process, the key lies in the relative positioning between the spherical bearing 19 and the seat flange 21 on the screw conveyor 18. If the problem of rapid relative positioning between the spherical bearing 19 and the seat flange 21 can be solved, the installation efficiency of the screw conveyor 18 will be greatly improved.

[0042] In order to achieve rapid positioning between the spherical bearing 19 of the screw conveyor 18 and the seat flange 21, the present invention provides two guide rails 22 in the screw machine mounting hole of the drive box 121, and an anti-twist block 23 is provided on the spherical bearing of the screw conveyor 18. Figure 3 , 4As shown, two guide rails 22 are laid in the inner hole of the drive box 121. Taking the top surface of the guide rails 22 as a reference, each guide rail 22 includes a horizontal section 221 at the rear end and an inclined section 222 at the front end. Taking the opposite side surfaces of the two guide rails 22 as a reference, each guide rail 22 includes a variable spacing section 223 at the rear end and an equal spacing section 224. In the horizontal section 221, the top surfaces of the two guide rails 22 are both horizontal planes. In the inclined section 222, the top surfaces of the two guide rails 22 are both inclined surfaces that are inclined downward from front to back. In the variable spacing section 223, inclined surfaces are provided on the opposite side surfaces of the two guide rails 22, which make the channel surrounded by the two guide rails 22 form an "eight" shape at the rear end. In the equal spacing section 224, the opposite sides of the two guide rails 22 are parallel to each other, and the spacing between them is equal.

[0043] like Figure 6 As shown, there are two anti-twist blocks 23, each of which is fixedly mounted on the joint bearing 19 by screws, and can cooperate with the two guide rails 22 respectively. Specifically, the lower side surfaces of the two anti-twist blocks 23 are slidably matched with the top surfaces of the two guide rails 22, and the distance between the two opposite side surfaces of the two anti-twist blocks 23 is less than the distance between the opposite side surfaces of the two guide rails 22, thereby forming a limit groove 101. When the joint bearing 19 has a tendency to rotate around the axis, the two guide rails 22 can prevent the rotation of the joint bearing 19 by blocking with the anti-twist blocks 23. The length of the variable spacing section of the guide rail 22 is greater than the length of the horizontal section of the guide rail 22. In the process of the screw conveyor 18 advancing forward, the inclined section is used to compensate for the increase in resistance caused by the decrease in the gap between the variable spacing section and the anti-twist block 23. At this time, if the screw conveyor 18 continues to be advanced, the anti-twist block 23 will enter the equal spacing section of the two guide rails 22, thereby further reducing the gap between the anti-twist block 23 and the guide rail 22, and achieving more accurate positioning of the screw conveyor 18.

[0044] When the joint bearing 19 moves to the front end of the guide rail 22, the guide cone 191 provided at the front end of the joint bearing 19 enters the center hole of the seat flange 21. At this time, if the screw conveyor 18 continues to be pushed forward, the joint bearing 19 will be separated from the guide rail 22 and move forward to the right position. The seat flange 21 and the bearing flange 20 are fixed by tightening bolts to complete the installation of the screw conveyor 18. In the process of the screw conveyor 18 being pushed forward, in order to prevent it from colliding with the main drive and to prevent its front end from tilting and leaving the guide rail 22, in this embodiment, an anti-collision block 24 is also provided on the inner wall of the drive box 121. The anti-collision block 24 is in a strip shape and there are multiple anti-collision blocks arranged around the center line of the screw machine installation hole.

[0045] The following will introduce the installation process of the screw conveyor in detail in combination with the structure of the tunneling machine that can use the central screw conveyor to discharge slag of the present invention:

[0046] The installation process of the screw conveyor of the tunneling machine capable of using the central screw machine to discharge slag is divided into four processes: initial overlap, inclined section overlap, seat flange overlap and fixation.

[0047] Initial overlap: Figure 7 , 8 As shown, before the screw conveyor 18 moves to this state, the surrounding space is relatively spacious, and there is no visual blind spot problem during installation. Starting from the time when the spherical bearing 19 on the screw conveyor 18 is overlapped with the guide rail 22, the visual blind spot begins to appear. At this time, the spherical bearing 19 is overlapped on the guide rail 22, and the rear part is overlapped on the support of the segment assembly machine 15 through the screw conveyor support. The gap between the anti-twist block 23 on the spherical bearing 19 and the guide rail 22 is A. The gap A ensures that the spherical bearing can be smoothly installed between the guide rails 22. The spherical bearing 19 is located in the horizontal section and the variable spacing section of the guide rail.

[0048] Inclined section overlap: As shown in Figures 9 and 10, the screw conveyor 18 moves forward from the initial overlap state along the guide rail 22 through the horizontal section 221 of the guide rail and enters the inclined section 222 of the guide rail 22. The anti-collision block 24 can limit the central position of the joint bearing 19 in the mounting hole to prevent the anti-twist block 23 from separating from the guide rail 22, thereby ensuring that the joint bearing 19 does not undergo circumferential deflection. At this time, the gap between the joint anti-twist block 23 on the joint bearing 19 and the guide rail 22 is B, and the gap B is smaller than the gap A, thereby ensuring that the circumferential deflection of the joint bearing 19 is reduced and the precision is more accurate. At this time, the joint bearing 19 enters the inclined section 222 of the guide rail 22, reducing the resistance caused by the reduced gap between the anti-twist block 23 and the guide rail 22, thereby facilitating the forward movement of the screw conveyor 18.

[0049] Overlap before docking: Fig.11 , 12 As shown, the screw conveyor 18 completely passes through the inclined section 222, and the anti-twist block 23 moves axially through the inclined section 222 and enters the equally spaced section 224 of the guide rail 22. At this time, the anti-collision block 24 in the circumferential direction of the joint bearing 19 can still ensure that the joint bearing 19 is located at the center of the installation hole, preventing the anti-twist block 23 from separating from the guide rail 22, thereby ensuring that the joint bearing 19 does not deflect circumferentially. At this time, the gap between the anti-twist block 23 and the guide rail 22 is C, and the gap C is smaller than the gap B, ensuring that the circumferential deflection of the joint bearing 19 is further reduced, and the precision is more accurate. When the joint bearing 19 moves to be flush with the front end of the guide rail 22, the distance between the joint bearing 19 and the seat flange 21 is E, and the length of the guide cone 191 at the front of the joint bearing 19 is greater than the distance E (that is, the front end of the guide cone 191 of the joint bearing 19 enters the seat flange), and it is necessary to ensure that there is a gap D between the circumference of the guide cone 191 of the joint bearing 19 and the seat flange, so that the joint bearing can continue to be installed smoothly.

[0050] like Figure 1 , 2The figure shows the screw conveyor in the completed installation state, the spherical bearing 19 and the guide rail 22 are completely separated, and the distance between the two is the gap F, and the gap between the anti-twist block 23 and the guide rail 22 is still C, ensuring that the connecting holes of the spherical bearing and the seat flange can correspond. At this time, the bearing flange of the spherical bearing and the seat flange are connected by tightening bolts, and the screw conveyor is in the completed installation state.

[0051] Embodiment 2 of the tunneling machine of the present invention that can use a central screw machine to discharge slag:

[0052] In the embodiment 1 of the tunnel boring machine that can use the central screw conveyor to discharge slag of the present invention, the rear end of the guide rail 22 only extends to a position where the surrounding space is still small, so a variable spacing section is provided at the rear end of the guide rail to be able to capture the delivered screw conveyor from a larger range. In this embodiment, the rear end of the guide rail is extended so that the rear end is at a position where the surrounding space is relatively open, so that the variable spacing section is no longer required.

[0053] Embodiment 3 of the tunneling machine of the present invention that can use a central screw machine to discharge slag:

[0054] In the embodiments 1 and 2 of the tunneling machine that can use the central screw conveyor to discharge slag of the present invention, two anti-twist blocks are provided on the joint bearing of the screw conveyor, and the two anti-twist blocks are respectively matched with the two guide rails. In this embodiment, only one anti-twist block is provided, and the positioning of the screw conveyor can be achieved by adjusting the slot width of the limit slot between the two guide rails.

[0055] Embodiment 4 of the tunneling machine of the present invention that can use a central screw machine to discharge slag:

[0056] In the embodiments 1, 2 and 3 of the tunnel boring machine that can use the center screw machine to discharge slag of the present invention, in order to prevent the guide rail from generating a reaction due to interference when the joint bearing and the seat flange are positioned, the top surface of the guide rail is set as a transition support surface, which then plays a supporting role during the advancement process and then separates from the joint bearing. In this embodiment, by improving the machining and installation accuracy of the guide rail, the top surface of the guide rail cooperates with the joint bearing throughout the entire process, which plays a role in positioning the joint bearing throughout the entire process.

[0057] Embodiment 5 of the tunneling machine of the present invention that can use a central screw machine to discharge slag:

[0058] In the embodiments 1, 2, 3 and 4 of the tunneling machine that can use the central screw conveyor to discharge slag of the present invention, in order to prevent the screw conveyor from hitting the drive box and escaping from the limit groove, an anti-collision block is provided in the inner hole of the drive box. In this embodiment, the anti-collision block is eliminated by adding position constraints to the screw conveyor during the installation process.

Claims

1. A tunneling machine that can use a central screw conveyor to discharge slag, comprising a main machine, the main machine comprising a shield, a cutter head and a main drive, the main drive comprising a drive box, a screw conveyor is installed in the inner hole of the drive box through a seat flange, and a spherical bearing is provided on the screw conveyor, characterized in that: Opposite guide rails are provided in the inner hole of the drive box. Taking the opposite surfaces of the two guide rails as a reference, the guide rails include an equidistant section at the front end and a variable-spacing section at the rear end. The variable-spacing sections of the two guide rails form an "eight" shape with a smaller front and a larger rear. Taking the top surfaces of the two guide rails as a reference, the guide rails include an inclined section at the front end and a horizontal section at the rear end. The top surfaces of the inclined sections slope downward from the back to the front, and there is an overlapping part between the inclined sections and the variable-spacing sections in the front-to-back direction. An anti-twist block corresponding to the guide rail is provided on the joint bearing, and a limiting groove corresponding to the anti-twist block is defined between the two guide rails. The limiting groove cooperates with the anti-twist block to limit the rotation of the screw conveyor.

2. The tunnel boring machine capable of discharging slag using a central screw machine according to claim 1, characterized in that: The top surface of the guide rail constitutes a supporting surface for supporting the spherical bearing.

3. The tunnel boring machine capable of discharging slag using a central screw machine according to claim 2, characterized in that: The supporting surface is a transition supporting surface. After the screw conveyor is installed in place, the spherical bearing is separated from the supporting surface.

4. The tunnel boring machine capable of discharging slag using a central screw machine according to claim 3, characterized in that: A guide cone is provided at the front end of the spherical bearing. When the spherical bearing moves to the front end of the guide rail, the guide cone extends into the center hole of the seat flange.

5. The tunnel boring machine capable of using a central screw machine to discharge slag according to claim 1 or 2, characterized in that: An anti-collision block is provided in the inner hole of the driving box and is used for limiting the position of the screw conveyor to prevent the screw conveyor from colliding with the driving box.

6. The tunnel boring machine capable of using a central screw machine to discharge slag according to claim 5, characterized in that: The dimension of the anti-collision block in the radial direction of the screw conveyor is greater than the swing distance dimension when the spherical bearing is separated from the limiting groove.

7. The tunnel boring machine capable of discharging slag using a central screw machine according to claim 1 or 2, characterized in that: The tunnel boring machine also includes a segment assembler, and the rear end of the screw conveyor is mounted on the segment assembler through the cooperation of a slide rail and a slide block.

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